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linux/net/rxrpc/sendmsg.c

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rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
/* AF_RXRPC sendmsg() implementation.
*
* Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/net.h>
#include <linux/gfp.h>
#include <linux/skbuff.h>
#include <linux/export.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include "ar-internal.h"
rxrpc Move enum rxrpc_command to sendmsg.c Move enum rxrpc_command to sendmsg.c as it's now only used in that file. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-04 12:25:21 +00:00
enum rxrpc_command {
RXRPC_CMD_SEND_DATA, /* send data message */
RXRPC_CMD_SEND_ABORT, /* request abort generation */
RXRPC_CMD_ACCEPT, /* [server] accept incoming call */
RXRPC_CMD_REJECT_BUSY, /* [server] reject a call as busy */
};
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
/*
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
* wait for space to appear in the transmit/ACK window
* - caller holds the socket locked
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
*/
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
struct rxrpc_call *call,
long *timeo)
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
{
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
DECLARE_WAITQUEUE(myself, current);
int ret;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
_enter(",{%u,%u,%u}",
call->tx_hard_ack, call->tx_top, call->tx_winsize);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
add_wait_queue(&call->waitq, &myself);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
for (;;) {
set_current_state(TASK_INTERRUPTIBLE);
ret = 0;
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
if (call->tx_top - call->tx_hard_ack < call->tx_winsize)
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
break;
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
if (call->state >= RXRPC_CALL_COMPLETE) {
ret = -call->error;
break;
}
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
if (signal_pending(current)) {
ret = sock_intr_errno(*timeo);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
break;
}
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Add a tracepoint to follow the life of a packet in the Tx buffer Add a tracepoint to follow the insertion of a packet into the transmit buffer, its transmission and its rotation out of the buffer. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-17 09:49:13 +00:00
trace_rxrpc_transmit(call, rxrpc_transmit_wait);
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
release_sock(&rx->sk);
*timeo = schedule_timeout(*timeo);
lock_sock(&rx->sk);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
}
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
remove_wait_queue(&call->waitq, &myself);
set_current_state(TASK_RUNNING);
_leave(" = %d", ret);
return ret;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
}
/*
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
* Schedule an instant Tx resend.
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
*/
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
static inline void rxrpc_instant_resend(struct rxrpc_call *call, int ix)
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
{
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
spin_lock_bh(&call->lock);
if (call->state < RXRPC_CALL_COMPLETE) {
call->rxtx_annotations[ix] = RXRPC_TX_ANNO_RETRANS;
if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc_queue_call(call);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
}
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
spin_unlock_bh(&call->lock);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
}
/*
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
* Queue a DATA packet for transmission, set the resend timeout and send the
* packet immediately
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
*/
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
static void rxrpc_queue_packet(struct rxrpc_call *call, struct sk_buff *skb,
bool last)
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
{
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
rxrpc_seq_t seq = sp->hdr.seq;
int ret, ix;
_net("queue skb %p [%d]", skb, seq);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
ASSERTCMP(seq, ==, call->tx_top + 1);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Preset timestamp on Tx sk_buffs Set the timestamp on sk_buffs holding packets to be transmitted before queueing them because the moment the packet is on the queue it can be seen by the retransmission algorithm - which may see a completely random timestamp. If the retransmission algorithm sees such a timestamp, it may retransmit the packet and, in future, tell the congestion management algorithm that the retransmit timer expired. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-23 12:17:33 +00:00
/* We have to set the timestamp before queueing as the retransmit
* algorithm can see the packet as soon as we queue it.
*/
skb->tstamp = ktime_get_real();
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
ix = seq & RXRPC_RXTX_BUFF_MASK;
rxrpc: Improve skb tracing Improve sk_buff tracing within AF_RXRPC by the following means: (1) Use an enum to note the event type rather than plain integers and use an array of event names rather than a big multi ?: list. (2) Distinguish Rx from Tx packets and account them separately. This requires the call phase to be tracked so that we know what we might find in rxtx_buffer[]. (3) Add a parameter to rxrpc_{new,see,get,free}_skb() to indicate the event type. (4) A pair of 'rotate' events are added to indicate packets that are about to be rotated out of the Rx and Tx windows. (5) A pair of 'lost' events are added, along with rxrpc_lose_skb() for packet loss injection recording. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-17 09:49:14 +00:00
rxrpc_get_skb(skb, rxrpc_skb_tx_got);
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
call->rxtx_annotations[ix] = RXRPC_TX_ANNO_UNACK;
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
smp_wmb();
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
call->rxtx_buffer[ix] = skb;
call->tx_top = seq;
rxrpc: Add a tracepoint to follow the life of a packet in the Tx buffer Add a tracepoint to follow the insertion of a packet into the transmit buffer, its transmission and its rotation out of the buffer. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-17 09:49:13 +00:00
if (last) {
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
set_bit(RXRPC_CALL_TX_LAST, &call->flags);
rxrpc: Add a tracepoint to follow the life of a packet in the Tx buffer Add a tracepoint to follow the insertion of a packet into the transmit buffer, its transmission and its rotation out of the buffer. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-17 09:49:13 +00:00
trace_rxrpc_transmit(call, rxrpc_transmit_queue_last);
} else if (sp->hdr.flags & RXRPC_REQUEST_ACK) {
trace_rxrpc_transmit(call, rxrpc_transmit_queue_reqack);
} else {
trace_rxrpc_transmit(call, rxrpc_transmit_queue);
}
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
_debug("________awaiting reply/ACK__________");
write_lock_bh(&call->state_lock);
switch (call->state) {
case RXRPC_CALL_CLIENT_SEND_REQUEST:
call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
break;
case RXRPC_CALL_SERVER_ACK_REQUEST:
call->state = RXRPC_CALL_SERVER_SEND_REPLY;
if (!last)
break;
case RXRPC_CALL_SERVER_SEND_REPLY:
call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
break;
default:
break;
}
write_unlock_bh(&call->state_lock);
}
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
if (seq == 1 && rxrpc_is_client_call(call))
rxrpc_expose_client_call(call);
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Don't store the rxrpc header in the Tx queue sk_buffs Don't store the rxrpc protocol header in sk_buffs on the transmit queue, but rather generate it on the fly and pass it to kernel_sendmsg() as a separate iov. This reduces the amount of storage required. Note that the security header is still stored in the sk_buff as it may get encrypted along with the data (and doesn't change with each transmission). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-21 23:29:31 +00:00
ret = rxrpc_send_data_packet(call, skb);
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
if (ret < 0) {
_debug("need instant resend %d", ret);
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
rxrpc_instant_resend(call, ix);
rxrpc: Need to start the resend timer on initial transmission When a DATA packet has its initial transmission, we may need to start or adjust the resend timer. Without this we end up relying on being sent a NACK to initiate the resend. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-23 11:39:23 +00:00
} else {
unsigned long resend_at;
resend_at = jiffies + msecs_to_jiffies(rxrpc_resend_timeout);
if (time_before(resend_at, call->resend_at)) {
call->resend_at = resend_at;
rxrpc_set_timer(call);
}
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
}
rxrpc: Improve skb tracing Improve sk_buff tracing within AF_RXRPC by the following means: (1) Use an enum to note the event type rather than plain integers and use an array of event names rather than a big multi ?: list. (2) Distinguish Rx from Tx packets and account them separately. This requires the call phase to be tracked so that we know what we might find in rxtx_buffer[]. (3) Add a parameter to rxrpc_{new,see,get,free}_skb() to indicate the event type. (4) A pair of 'rotate' events are added to indicate packets that are about to be rotated out of the Rx and Tx windows. (5) A pair of 'lost' events are added, along with rxrpc_lose_skb() for packet loss injection recording. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-17 09:49:14 +00:00
rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_leave("");
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
}
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
/*
* send data through a socket
* - must be called in process context
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
* - caller holds the socket locked
*/
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
static int rxrpc_send_data(struct rxrpc_sock *rx,
struct rxrpc_call *call,
struct msghdr *msg, size_t len)
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
{
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
struct rxrpc_skb_priv *sp;
struct sk_buff *skb;
struct sock *sk = &rx->sk;
long timeo;
bool more;
int ret, copied;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
/* this should be in poll */
sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
return -EPIPE;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
more = msg->msg_flags & MSG_MORE;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
skb = call->tx_pending;
call->tx_pending = NULL;
rxrpc: Improve skb tracing Improve sk_buff tracing within AF_RXRPC by the following means: (1) Use an enum to note the event type rather than plain integers and use an array of event names rather than a big multi ?: list. (2) Distinguish Rx from Tx packets and account them separately. This requires the call phase to be tracked so that we know what we might find in rxtx_buffer[]. (3) Add a parameter to rxrpc_{new,see,get,free}_skb() to indicate the event type. (4) A pair of 'rotate' events are added to indicate packets that are about to be rotated out of the Rx and Tx windows. (5) A pair of 'lost' events are added, along with rxrpc_lose_skb() for packet loss injection recording. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-17 09:49:14 +00:00
rxrpc_see_skb(skb, rxrpc_skb_tx_seen);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
copied = 0;
do {
rxrpc: Expedite ping response transmission Expedite the transmission of a response to a PING ACK by sending it from sendmsg if one is pending. We're most likely to see a PING ACK during the client call Tx phase as the other side may use it to determine a number of parameters, such as the client's receive window size, the RTT and whether the client is doing slow start (similar to RFC5681). If we don't expedite it, it's left to the background processing thread to transmit. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-21 23:29:31 +00:00
/* Check to see if there's a ping ACK to reply to. */
if (call->ackr_reason == RXRPC_ACK_PING_RESPONSE)
rxrpc_send_call_packet(call, RXRPC_PACKET_TYPE_ACK);
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
if (!skb) {
size_t size, chunk, max, space;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_debug("alloc");
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
if (call->tx_top - call->tx_hard_ack >=
call->tx_winsize) {
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
ret = -EAGAIN;
if (msg->msg_flags & MSG_DONTWAIT)
goto maybe_error;
ret = rxrpc_wait_for_tx_window(rx, call,
&timeo);
if (ret < 0)
goto maybe_error;
}
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Fix the basic transmit DATA packet content size at 1412 bytes Fix the basic transmit DATA packet content size at 1412 bytes so that they can be arbitrarily assembled into jumbo packets. In the future, I'm thinking of moving to keeping a jumbo packet header at the beginning of each packet in the Tx queue and creating the packet header on the spot when kernel_sendmsg() is invoked. That way, jumbo packets can be assembled on the spur of the moment for (re-)transmission. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-17 09:49:12 +00:00
max = RXRPC_JUMBO_DATALEN;
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
max -= call->conn->security_size;
max &= ~(call->conn->size_align - 1UL);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
chunk = max;
if (chunk > msg_data_left(msg) && !more)
chunk = msg_data_left(msg);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
space = chunk + call->conn->size_align;
space &= ~(call->conn->size_align - 1UL);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Don't store the rxrpc header in the Tx queue sk_buffs Don't store the rxrpc protocol header in sk_buffs on the transmit queue, but rather generate it on the fly and pass it to kernel_sendmsg() as a separate iov. This reduces the amount of storage required. Note that the security header is still stored in the sk_buff as it may get encrypted along with the data (and doesn't change with each transmission). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-21 23:29:31 +00:00
size = space + call->conn->security_size;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_debug("SIZE: %zu/%zu/%zu", chunk, space, size);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
/* create a buffer that we can retain until it's ACK'd */
skb = sock_alloc_send_skb(
sk, size, msg->msg_flags & MSG_DONTWAIT, &ret);
if (!skb)
goto maybe_error;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Improve skb tracing Improve sk_buff tracing within AF_RXRPC by the following means: (1) Use an enum to note the event type rather than plain integers and use an array of event names rather than a big multi ?: list. (2) Distinguish Rx from Tx packets and account them separately. This requires the call phase to be tracked so that we know what we might find in rxtx_buffer[]. (3) Add a parameter to rxrpc_{new,see,get,free}_skb() to indicate the event type. (4) A pair of 'rotate' events are added to indicate packets that are about to be rotated out of the Rx and Tx windows. (5) A pair of 'lost' events are added, along with rxrpc_lose_skb() for packet loss injection recording. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-17 09:49:14 +00:00
rxrpc_new_skb(skb, rxrpc_skb_tx_new);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_debug("ALLOC SEND %p", skb);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
ASSERTCMP(skb->mark, ==, 0);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Don't store the rxrpc header in the Tx queue sk_buffs Don't store the rxrpc protocol header in sk_buffs on the transmit queue, but rather generate it on the fly and pass it to kernel_sendmsg() as a separate iov. This reduces the amount of storage required. Note that the security header is still stored in the sk_buff as it may get encrypted along with the data (and doesn't change with each transmission). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-21 23:29:31 +00:00
_debug("HS: %u", call->conn->security_size);
skb_reserve(skb, call->conn->security_size);
skb->len += call->conn->security_size;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
sp = rxrpc_skb(skb);
sp->remain = chunk;
if (sp->remain > skb_tailroom(skb))
sp->remain = skb_tailroom(skb);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_net("skb: hr %d, tr %d, hl %d, rm %d",
skb_headroom(skb),
skb_tailroom(skb),
skb_headlen(skb),
sp->remain);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
skb->ip_summed = CHECKSUM_UNNECESSARY;
}
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_debug("append");
sp = rxrpc_skb(skb);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
/* append next segment of data to the current buffer */
if (msg_data_left(msg) > 0) {
int copy = skb_tailroom(skb);
ASSERTCMP(copy, >, 0);
if (copy > msg_data_left(msg))
copy = msg_data_left(msg);
if (copy > sp->remain)
copy = sp->remain;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_debug("add");
ret = skb_add_data(skb, &msg->msg_iter, copy);
_debug("added");
if (ret < 0)
goto efault;
sp->remain -= copy;
skb->mark += copy;
copied += copy;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
}
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
/* check for the far side aborting the call or a network error
* occurring */
if (call->state == RXRPC_CALL_COMPLETE)
goto call_terminated;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
/* add the packet to the send queue if it's now full */
if (sp->remain <= 0 ||
(msg_data_left(msg) == 0 && !more)) {
struct rxrpc_connection *conn = call->conn;
uint32_t seq;
size_t pad;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
/* pad out if we're using security */
if (conn->security_ix) {
pad = conn->security_size + skb->mark;
pad = conn->size_align - pad;
pad &= conn->size_align - 1;
_debug("pad %zu", pad);
if (pad)
memset(skb_put(skb, pad), 0, pad);
}
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
seq = call->tx_top + 1;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
sp->hdr.seq = seq;
sp->hdr._rsvd = 0;
rxrpc: Don't store the rxrpc header in the Tx queue sk_buffs Don't store the rxrpc protocol header in sk_buffs on the transmit queue, but rather generate it on the fly and pass it to kernel_sendmsg() as a separate iov. This reduces the amount of storage required. Note that the security header is still stored in the sk_buff as it may get encrypted along with the data (and doesn't change with each transmission). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-21 23:29:31 +00:00
sp->hdr.flags = conn->out_clientflag;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
if (msg_data_left(msg) == 0 && !more)
sp->hdr.flags |= RXRPC_LAST_PACKET;
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
else if (call->tx_top - call->tx_hard_ack <
call->tx_winsize)
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
sp->hdr.flags |= RXRPC_MORE_PACKETS;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
ret = conn->security->secure_packet(
rxrpc: Don't store the rxrpc header in the Tx queue sk_buffs Don't store the rxrpc protocol header in sk_buffs on the transmit queue, but rather generate it on the fly and pass it to kernel_sendmsg() as a separate iov. This reduces the amount of storage required. Note that the security header is still stored in the sk_buff as it may get encrypted along with the data (and doesn't change with each transmission). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-21 23:29:31 +00:00
call, skb, skb->mark, skb->head);
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
if (ret < 0)
goto out;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc_queue_packet(call, skb, !msg_data_left(msg) && !more);
skb = NULL;
}
} while (msg_data_left(msg) > 0);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
success:
ret = copied;
out:
call->tx_pending = skb;
_leave(" = %d", ret);
return ret;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
call_terminated:
rxrpc: Improve skb tracing Improve sk_buff tracing within AF_RXRPC by the following means: (1) Use an enum to note the event type rather than plain integers and use an array of event names rather than a big multi ?: list. (2) Distinguish Rx from Tx packets and account them separately. This requires the call phase to be tracked so that we know what we might find in rxtx_buffer[]. (3) Add a parameter to rxrpc_{new,see,get,free}_skb() to indicate the event type. (4) A pair of 'rotate' events are added to indicate packets that are about to be rotated out of the Rx and Tx windows. (5) A pair of 'lost' events are added, along with rxrpc_lose_skb() for packet loss injection recording. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-17 09:49:14 +00:00
rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_leave(" = %d", -call->error);
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
return -call->error;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
maybe_error:
if (copied)
goto success;
goto out;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
efault:
ret = -EFAULT;
goto out;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
}
/*
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
* extract control messages from the sendmsg() control buffer
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
*/
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
static int rxrpc_sendmsg_cmsg(struct msghdr *msg,
unsigned long *user_call_ID,
enum rxrpc_command *command,
u32 *abort_code,
bool *_exclusive)
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
{
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
struct cmsghdr *cmsg;
bool got_user_ID = false;
int len;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
*command = RXRPC_CMD_SEND_DATA;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
if (msg->msg_controllen == 0)
return -EINVAL;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
for_each_cmsghdr(cmsg, msg) {
if (!CMSG_OK(msg, cmsg))
return -EINVAL;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
len = cmsg->cmsg_len - CMSG_ALIGN(sizeof(struct cmsghdr));
_debug("CMSG %d, %d, %d",
cmsg->cmsg_level, cmsg->cmsg_type, len);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
if (cmsg->cmsg_level != SOL_RXRPC)
continue;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
switch (cmsg->cmsg_type) {
case RXRPC_USER_CALL_ID:
if (msg->msg_flags & MSG_CMSG_COMPAT) {
if (len != sizeof(u32))
return -EINVAL;
*user_call_ID = *(u32 *) CMSG_DATA(cmsg);
} else {
if (len != sizeof(unsigned long))
return -EINVAL;
*user_call_ID = *(unsigned long *)
CMSG_DATA(cmsg);
}
_debug("User Call ID %lx", *user_call_ID);
got_user_ID = true;
break;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
case RXRPC_ABORT:
if (*command != RXRPC_CMD_SEND_DATA)
return -EINVAL;
*command = RXRPC_CMD_SEND_ABORT;
if (len != sizeof(*abort_code))
return -EINVAL;
*abort_code = *(unsigned int *) CMSG_DATA(cmsg);
_debug("Abort %x", *abort_code);
if (*abort_code == 0)
return -EINVAL;
break;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
case RXRPC_ACCEPT:
if (*command != RXRPC_CMD_SEND_DATA)
return -EINVAL;
*command = RXRPC_CMD_ACCEPT;
if (len != 0)
return -EINVAL;
break;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
case RXRPC_EXCLUSIVE_CALL:
*_exclusive = true;
if (len != 0)
return -EINVAL;
break;
default:
return -EINVAL;
}
}
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
if (!got_user_ID)
return -EINVAL;
_leave(" = 0");
return 0;
}
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
/*
* Create a new client call for sendmsg().
*/
static struct rxrpc_call *
rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
unsigned long user_call_ID, bool exclusive)
{
struct rxrpc_conn_parameters cp;
struct rxrpc_call *call;
struct key *key;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_enter("");
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
if (!msg->msg_name)
return ERR_PTR(-EDESTADDRREQ);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
key = rx->key;
if (key && !rx->key->payload.data[0])
key = NULL;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
memset(&cp, 0, sizeof(cp));
cp.local = rx->local;
cp.key = rx->key;
cp.security_level = rx->min_sec_level;
cp.exclusive = rx->exclusive | exclusive;
cp.service_id = srx->srx_service;
call = rxrpc_new_client_call(rx, &cp, srx, user_call_ID, GFP_KERNEL);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_leave(" = %p\n", call);
return call;
}
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
/*
* send a message forming part of a client call through an RxRPC socket
* - caller holds the socket locked
* - the socket may be either a client socket or a server socket
*/
int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
{
enum rxrpc_command cmd;
struct rxrpc_call *call;
unsigned long user_call_ID = 0;
bool exclusive = false;
u32 abort_code = 0;
int ret;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_enter("");
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
ret = rxrpc_sendmsg_cmsg(msg, &user_call_ID, &cmd, &abort_code,
&exclusive);
if (ret < 0)
return ret;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
if (cmd == RXRPC_CMD_ACCEPT) {
if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
return -EINVAL;
call = rxrpc_accept_call(rx, user_call_ID, NULL);
if (IS_ERR(call))
return PTR_ERR(call);
rxrpc: Improve the call tracking tracepoint Improve the call tracking tracepoint by showing more differentiation between some of the put and get events, including: (1) Getting and putting refs for the socket call user ID tree. (2) Getting and putting refs for queueing and failing to queue the call processor work item. Note that these aren't necessarily used in this patch, but will be taken advantage of in future patches. An enum is added for the event subtype numbers rather than coding them directly as decimal numbers and a table of 3-letter strings is provided rather than a sequence of ?: operators. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 13:34:21 +00:00
rxrpc_put_call(call, rxrpc_call_put);
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
return 0;
}
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
call = rxrpc_find_call_by_user_ID(rx, user_call_ID);
if (!call) {
if (cmd != RXRPC_CMD_SEND_DATA)
return -EBADSLT;
call = rxrpc_new_client_call_for_sendmsg(rx, msg, user_call_ID,
exclusive);
if (IS_ERR(call))
return PTR_ERR(call);
}
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_debug("CALL %d USR %lx ST %d on CONN %p",
call->debug_id, call->user_call_ID, call->state, call->conn);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
if (call->state >= RXRPC_CALL_COMPLETE) {
/* it's too late for this call */
ret = -ESHUTDOWN;
} else if (cmd == RXRPC_CMD_SEND_ABORT) {
ret = 0;
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
if (rxrpc_abort_call("CMD", call, 0, abort_code, ECONNABORTED))
ret = rxrpc_send_call_packet(call,
RXRPC_PACKET_TYPE_ABORT);
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
} else if (cmd != RXRPC_CMD_SEND_DATA) {
ret = -EINVAL;
} else if (rxrpc_is_client_call(call) &&
call->state != RXRPC_CALL_CLIENT_SEND_REQUEST) {
/* request phase complete for this client call */
ret = -EPROTO;
} else if (rxrpc_is_service_call(call) &&
call->state != RXRPC_CALL_SERVER_ACK_REQUEST &&
call->state != RXRPC_CALL_SERVER_SEND_REPLY) {
/* Reply phase not begun or not complete for service call. */
ret = -EPROTO;
} else {
ret = rxrpc_send_data(rx, call, msg, len);
}
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Improve the call tracking tracepoint Improve the call tracking tracepoint by showing more differentiation between some of the put and get events, including: (1) Getting and putting refs for the socket call user ID tree. (2) Getting and putting refs for queueing and failing to queue the call processor work item. Note that these aren't necessarily used in this patch, but will be taken advantage of in future patches. An enum is added for the event subtype numbers rather than coding them directly as decimal numbers and a table of 3-letter strings is provided rather than a sequence of ?: operators. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-07 13:34:21 +00:00
rxrpc_put_call(call, rxrpc_call_put);
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_leave(" = %d", ret);
return ret;
}
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
/**
* rxrpc_kernel_send_data - Allow a kernel service to send data on a call
* @sock: The socket the call is on
* @call: The call to send data through
* @msg: The data to send
* @len: The amount of data to send
*
* Allow a kernel service to send data on a call. The call must be in an state
* appropriate to sending data. No control data should be supplied in @msg,
* nor should an address be supplied. MSG_MORE should be flagged if there's
* more data to come, otherwise this data will end the transmission phase.
*/
int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
struct msghdr *msg, size_t len)
{
int ret;
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
ASSERTCMP(msg->msg_name, ==, NULL);
ASSERTCMP(msg->msg_control, ==, NULL);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
lock_sock(sock->sk);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_debug("CALL %d USR %lx ST %d on CONN %p",
call->debug_id, call->user_call_ID, call->state, call->conn);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
if (call->state >= RXRPC_CALL_COMPLETE) {
ret = -ESHUTDOWN; /* it's too late for this call */
} else if (call->state != RXRPC_CALL_CLIENT_SEND_REQUEST &&
call->state != RXRPC_CALL_SERVER_ACK_REQUEST &&
call->state != RXRPC_CALL_SERVER_SEND_REPLY) {
ret = -EPROTO; /* request phase complete for this client call */
} else {
ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len);
}
release_sock(sock->sk);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
_leave(" = %d", ret);
return ret;
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
}
EXPORT_SYMBOL(rxrpc_kernel_send_data);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
/**
* rxrpc_kernel_abort_call - Allow a kernel service to abort a call
* @sock: The socket the call is on
* @call: The call to be aborted
* @abort_code: The abort code to stick into the ABORT packet
rxrpc: Add tracepoint for working out where aborts happen Add a tracepoint for working out where local aborts happen. Each tracepoint call is labelled with a 3-letter code so that they can be distinguished - and the DATA sequence number is added too where available. rxrpc_kernel_abort_call() also takes a 3-letter code so that AFS can indicate the circumstances when it aborts a call. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-06 21:19:51 +00:00
* @error: Local error value
* @why: 3-char string indicating why.
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
*
* Allow a kernel service to abort a call, if it's still in an abortable state.
*/
void rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
rxrpc: Add tracepoint for working out where aborts happen Add a tracepoint for working out where local aborts happen. Each tracepoint call is labelled with a 3-letter code so that they can be distinguished - and the DATA sequence number is added too where available. rxrpc_kernel_abort_call() also takes a 3-letter code so that AFS can indicate the circumstances when it aborts a call. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-06 21:19:51 +00:00
u32 abort_code, int error, const char *why)
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
{
rxrpc: Add tracepoint for working out where aborts happen Add a tracepoint for working out where local aborts happen. Each tracepoint call is labelled with a 3-letter code so that they can be distinguished - and the DATA sequence number is added too where available. rxrpc_kernel_abort_call() also takes a 3-letter code so that AFS can indicate the circumstances when it aborts a call. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-06 21:19:51 +00:00
_enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
lock_sock(sock->sk);
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
rxrpc: Rewrite the data and ack handling code Rewrite the data and ack handling code such that: (1) Parsing of received ACK and ABORT packets and the distribution and the filing of DATA packets happens entirely within the data_ready context called from the UDP socket. This allows us to process and discard ACK and ABORT packets much more quickly (they're no longer stashed on a queue for a background thread to process). (2) We avoid calling skb_clone(), pskb_pull() and pskb_trim(). We instead keep track of the offset and length of the content of each packet in the sk_buff metadata. This means we don't do any allocation in the receive path. (3) Jumbo DATA packet parsing is now done in data_ready context. Rather than cloning the packet once for each subpacket and pulling/trimming it, we file the packet multiple times with an annotation for each indicating which subpacket is there. From that we can directly calculate the offset and length. (4) A call's receive queue can be accessed without taking locks (memory barriers do have to be used, though). (5) Incoming calls are set up from preallocated resources and immediately made live. They can than have packets queued upon them and ACKs generated. If insufficient resources exist, DATA packet #1 is given a BUSY reply and other DATA packets are discarded). (6) sk_buffs no longer take a ref on their parent call. To make this work, the following changes are made: (1) Each call's receive buffer is now a circular buffer of sk_buff pointers (rxtx_buffer) rather than a number of sk_buff_heads spread between the call and the socket. This permits each sk_buff to be in the buffer multiple times. The receive buffer is reused for the transmit buffer. (2) A circular buffer of annotations (rxtx_annotations) is kept parallel to the data buffer. Transmission phase annotations indicate whether a buffered packet has been ACK'd or not and whether it needs retransmission. Receive phase annotations indicate whether a slot holds a whole packet or a jumbo subpacket and, if the latter, which subpacket. They also note whether the packet has been decrypted in place. (3) DATA packet window tracking is much simplified. Each phase has just two numbers representing the window (rx_hard_ack/rx_top and tx_hard_ack/tx_top). The hard_ack number is the sequence number before base of the window, representing the last packet the other side says it has consumed. hard_ack starts from 0 and the first packet is sequence number 1. The top number is the sequence number of the highest-numbered packet residing in the buffer. Packets between hard_ack+1 and top are soft-ACK'd to indicate they've been received, but not yet consumed. Four macros, before(), before_eq(), after() and after_eq() are added to compare sequence numbers within the window. This allows for the top of the window to wrap when the hard-ack sequence number gets close to the limit. Two flags, RXRPC_CALL_RX_LAST and RXRPC_CALL_TX_LAST, are added also to indicate when rx_top and tx_top point at the packets with the LAST_PACKET bit set, indicating the end of the phase. (4) Calls are queued on the socket 'receive queue' rather than packets. This means that we don't need have to invent dummy packets to queue to indicate abnormal/terminal states and we don't have to keep metadata packets (such as ABORTs) around (5) The offset and length of a (sub)packet's content are now passed to the verify_packet security op. This is currently expected to decrypt the packet in place and validate it. However, there's now nowhere to store the revised offset and length of the actual data within the decrypted blob (there may be a header and padding to skip) because an sk_buff may represent multiple packets, so a locate_data security op is added to retrieve these details from the sk_buff content when needed. (6) recvmsg() now has to handle jumbo subpackets, where each subpacket is individually secured and needs to be individually decrypted. The code to do this is broken out into rxrpc_recvmsg_data() and shared with the kernel API. It now iterates over the call's receive buffer rather than walking the socket receive queue. Additional changes: (1) The timers are condensed to a single timer that is set for the soonest of three timeouts (delayed ACK generation, DATA retransmission and call lifespan). (2) Transmission of ACK and ABORT packets is effected immediately from process-context socket ops/kernel API calls that cause them instead of them being punted off to a background work item. The data_ready handler still has to defer to the background, though. (3) A shutdown op is added to the AF_RXRPC socket so that the AFS filesystem can shut down the socket and flush its own work items before closing the socket to deal with any in-progress service calls. Future additional changes that will need to be considered: (1) Make sure that a call doesn't hog the front of the queue by receiving data from the network as fast as userspace is consuming it to the exclusion of other calls. (2) Transmit delayed ACKs from within recvmsg() when we've consumed sufficiently more packets to avoid the background work item needing to run. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-08 10:10:12 +00:00
if (rxrpc_abort_call(why, call, 0, abort_code, error))
rxrpc_send_call_packet(call, RXRPC_PACKET_TYPE_ABORT);
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
release_sock(sock->sk);
_leave("");
rxrpc: Split sendmsg from packet transmission code Split the sendmsg code from the packet transmission code (mostly to be found in output.c). Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
}
rxrpc: Rearrange net/rxrpc/sendmsg.c Rearrange net/rxrpc/sendmsg.c to be in a more logical order. This makes it easier to follow and eliminates forward declarations. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-02 21:39:45 +00:00
EXPORT_SYMBOL(rxrpc_kernel_abort_call);
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