forked from Minki/linux
a64bd93452
Reference count the number of packets in host stack, so that we don't stop the deallocation thread too early. If not, we can end up with xenvif_free permanently waiting for deallocation thread to unmap grefs. Reported-by: Thomas Leonard <talex5@gmail.com> Signed-off-by: Wei Liu <wei.liu2@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Zoltan Kiss <zoltan.kiss@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2144 lines
58 KiB
C
2144 lines
58 KiB
C
/*
|
|
* Back-end of the driver for virtual network devices. This portion of the
|
|
* driver exports a 'unified' network-device interface that can be accessed
|
|
* by any operating system that implements a compatible front end. A
|
|
* reference front-end implementation can be found in:
|
|
* drivers/net/xen-netfront.c
|
|
*
|
|
* Copyright (c) 2002-2005, K A Fraser
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License version 2
|
|
* as published by the Free Software Foundation; or, when distributed
|
|
* separately from the Linux kernel or incorporated into other
|
|
* software packages, subject to the following license:
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this source file (the "Software"), to deal in the Software without
|
|
* restriction, including without limitation the rights to use, copy, modify,
|
|
* merge, publish, distribute, sublicense, and/or sell copies of the Software,
|
|
* and to permit persons to whom the Software is furnished to do so, subject to
|
|
* the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
|
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
|
|
* IN THE SOFTWARE.
|
|
*/
|
|
|
|
#include "common.h"
|
|
|
|
#include <linux/kthread.h>
|
|
#include <linux/if_vlan.h>
|
|
#include <linux/udp.h>
|
|
#include <linux/highmem.h>
|
|
|
|
#include <net/tcp.h>
|
|
|
|
#include <xen/xen.h>
|
|
#include <xen/events.h>
|
|
#include <xen/interface/memory.h>
|
|
|
|
#include <asm/xen/hypercall.h>
|
|
#include <asm/xen/page.h>
|
|
|
|
/* Provide an option to disable split event channels at load time as
|
|
* event channels are limited resource. Split event channels are
|
|
* enabled by default.
|
|
*/
|
|
bool separate_tx_rx_irq = 1;
|
|
module_param(separate_tx_rx_irq, bool, 0644);
|
|
|
|
/* When guest ring is filled up, qdisc queues the packets for us, but we have
|
|
* to timeout them, otherwise other guests' packets can get stuck there
|
|
*/
|
|
unsigned int rx_drain_timeout_msecs = 10000;
|
|
module_param(rx_drain_timeout_msecs, uint, 0444);
|
|
unsigned int rx_drain_timeout_jiffies;
|
|
|
|
unsigned int xenvif_max_queues;
|
|
module_param_named(max_queues, xenvif_max_queues, uint, 0644);
|
|
MODULE_PARM_DESC(max_queues,
|
|
"Maximum number of queues per virtual interface");
|
|
|
|
/*
|
|
* This is the maximum slots a skb can have. If a guest sends a skb
|
|
* which exceeds this limit it is considered malicious.
|
|
*/
|
|
#define FATAL_SKB_SLOTS_DEFAULT 20
|
|
static unsigned int fatal_skb_slots = FATAL_SKB_SLOTS_DEFAULT;
|
|
module_param(fatal_skb_slots, uint, 0444);
|
|
|
|
static void xenvif_idx_release(struct xenvif_queue *queue, u16 pending_idx,
|
|
u8 status);
|
|
|
|
static void make_tx_response(struct xenvif_queue *queue,
|
|
struct xen_netif_tx_request *txp,
|
|
s8 st);
|
|
|
|
static inline int tx_work_todo(struct xenvif_queue *queue);
|
|
static inline int rx_work_todo(struct xenvif_queue *queue);
|
|
|
|
static struct xen_netif_rx_response *make_rx_response(struct xenvif_queue *queue,
|
|
u16 id,
|
|
s8 st,
|
|
u16 offset,
|
|
u16 size,
|
|
u16 flags);
|
|
|
|
static inline unsigned long idx_to_pfn(struct xenvif_queue *queue,
|
|
u16 idx)
|
|
{
|
|
return page_to_pfn(queue->mmap_pages[idx]);
|
|
}
|
|
|
|
static inline unsigned long idx_to_kaddr(struct xenvif_queue *queue,
|
|
u16 idx)
|
|
{
|
|
return (unsigned long)pfn_to_kaddr(idx_to_pfn(queue, idx));
|
|
}
|
|
|
|
#define callback_param(vif, pending_idx) \
|
|
(vif->pending_tx_info[pending_idx].callback_struct)
|
|
|
|
/* Find the containing VIF's structure from a pointer in pending_tx_info array
|
|
*/
|
|
static inline struct xenvif_queue *ubuf_to_queue(const struct ubuf_info *ubuf)
|
|
{
|
|
u16 pending_idx = ubuf->desc;
|
|
struct pending_tx_info *temp =
|
|
container_of(ubuf, struct pending_tx_info, callback_struct);
|
|
return container_of(temp - pending_idx,
|
|
struct xenvif_queue,
|
|
pending_tx_info[0]);
|
|
}
|
|
|
|
/* This is a miniumum size for the linear area to avoid lots of
|
|
* calls to __pskb_pull_tail() as we set up checksum offsets. The
|
|
* value 128 was chosen as it covers all IPv4 and most likely
|
|
* IPv6 headers.
|
|
*/
|
|
#define PKT_PROT_LEN 128
|
|
|
|
static u16 frag_get_pending_idx(skb_frag_t *frag)
|
|
{
|
|
return (u16)frag->page_offset;
|
|
}
|
|
|
|
static void frag_set_pending_idx(skb_frag_t *frag, u16 pending_idx)
|
|
{
|
|
frag->page_offset = pending_idx;
|
|
}
|
|
|
|
static inline pending_ring_idx_t pending_index(unsigned i)
|
|
{
|
|
return i & (MAX_PENDING_REQS-1);
|
|
}
|
|
|
|
bool xenvif_rx_ring_slots_available(struct xenvif_queue *queue, int needed)
|
|
{
|
|
RING_IDX prod, cons;
|
|
|
|
do {
|
|
prod = queue->rx.sring->req_prod;
|
|
cons = queue->rx.req_cons;
|
|
|
|
if (prod - cons >= needed)
|
|
return true;
|
|
|
|
queue->rx.sring->req_event = prod + 1;
|
|
|
|
/* Make sure event is visible before we check prod
|
|
* again.
|
|
*/
|
|
mb();
|
|
} while (queue->rx.sring->req_prod != prod);
|
|
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Returns true if we should start a new receive buffer instead of
|
|
* adding 'size' bytes to a buffer which currently contains 'offset'
|
|
* bytes.
|
|
*/
|
|
static bool start_new_rx_buffer(int offset, unsigned long size, int head,
|
|
bool full_coalesce)
|
|
{
|
|
/* simple case: we have completely filled the current buffer. */
|
|
if (offset == MAX_BUFFER_OFFSET)
|
|
return true;
|
|
|
|
/*
|
|
* complex case: start a fresh buffer if the current frag
|
|
* would overflow the current buffer but only if:
|
|
* (i) this frag would fit completely in the next buffer
|
|
* and (ii) there is already some data in the current buffer
|
|
* and (iii) this is not the head buffer.
|
|
* and (iv) there is no need to fully utilize the buffers
|
|
*
|
|
* Where:
|
|
* - (i) stops us splitting a frag into two copies
|
|
* unless the frag is too large for a single buffer.
|
|
* - (ii) stops us from leaving a buffer pointlessly empty.
|
|
* - (iii) stops us leaving the first buffer
|
|
* empty. Strictly speaking this is already covered
|
|
* by (ii) but is explicitly checked because
|
|
* netfront relies on the first buffer being
|
|
* non-empty and can crash otherwise.
|
|
* - (iv) is needed for skbs which can use up more than MAX_SKB_FRAGS
|
|
* slot
|
|
*
|
|
* This means we will effectively linearise small
|
|
* frags but do not needlessly split large buffers
|
|
* into multiple copies tend to give large frags their
|
|
* own buffers as before.
|
|
*/
|
|
BUG_ON(size > MAX_BUFFER_OFFSET);
|
|
if ((offset + size > MAX_BUFFER_OFFSET) && offset && !head &&
|
|
!full_coalesce)
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
struct netrx_pending_operations {
|
|
unsigned copy_prod, copy_cons;
|
|
unsigned meta_prod, meta_cons;
|
|
struct gnttab_copy *copy;
|
|
struct xenvif_rx_meta *meta;
|
|
int copy_off;
|
|
grant_ref_t copy_gref;
|
|
};
|
|
|
|
static struct xenvif_rx_meta *get_next_rx_buffer(struct xenvif_queue *queue,
|
|
struct netrx_pending_operations *npo)
|
|
{
|
|
struct xenvif_rx_meta *meta;
|
|
struct xen_netif_rx_request *req;
|
|
|
|
req = RING_GET_REQUEST(&queue->rx, queue->rx.req_cons++);
|
|
|
|
meta = npo->meta + npo->meta_prod++;
|
|
meta->gso_type = XEN_NETIF_GSO_TYPE_NONE;
|
|
meta->gso_size = 0;
|
|
meta->size = 0;
|
|
meta->id = req->id;
|
|
|
|
npo->copy_off = 0;
|
|
npo->copy_gref = req->gref;
|
|
|
|
return meta;
|
|
}
|
|
|
|
struct xenvif_rx_cb {
|
|
int meta_slots_used;
|
|
bool full_coalesce;
|
|
};
|
|
|
|
#define XENVIF_RX_CB(skb) ((struct xenvif_rx_cb *)(skb)->cb)
|
|
|
|
/*
|
|
* Set up the grant operations for this fragment. If it's a flipping
|
|
* interface, we also set up the unmap request from here.
|
|
*/
|
|
static void xenvif_gop_frag_copy(struct xenvif_queue *queue, struct sk_buff *skb,
|
|
struct netrx_pending_operations *npo,
|
|
struct page *page, unsigned long size,
|
|
unsigned long offset, int *head,
|
|
struct xenvif_queue *foreign_queue,
|
|
grant_ref_t foreign_gref)
|
|
{
|
|
struct gnttab_copy *copy_gop;
|
|
struct xenvif_rx_meta *meta;
|
|
unsigned long bytes;
|
|
int gso_type = XEN_NETIF_GSO_TYPE_NONE;
|
|
|
|
/* Data must not cross a page boundary. */
|
|
BUG_ON(size + offset > PAGE_SIZE<<compound_order(page));
|
|
|
|
meta = npo->meta + npo->meta_prod - 1;
|
|
|
|
/* Skip unused frames from start of page */
|
|
page += offset >> PAGE_SHIFT;
|
|
offset &= ~PAGE_MASK;
|
|
|
|
while (size > 0) {
|
|
BUG_ON(offset >= PAGE_SIZE);
|
|
BUG_ON(npo->copy_off > MAX_BUFFER_OFFSET);
|
|
|
|
bytes = PAGE_SIZE - offset;
|
|
|
|
if (bytes > size)
|
|
bytes = size;
|
|
|
|
if (start_new_rx_buffer(npo->copy_off,
|
|
bytes,
|
|
*head,
|
|
XENVIF_RX_CB(skb)->full_coalesce)) {
|
|
/*
|
|
* Netfront requires there to be some data in the head
|
|
* buffer.
|
|
*/
|
|
BUG_ON(*head);
|
|
|
|
meta = get_next_rx_buffer(queue, npo);
|
|
}
|
|
|
|
if (npo->copy_off + bytes > MAX_BUFFER_OFFSET)
|
|
bytes = MAX_BUFFER_OFFSET - npo->copy_off;
|
|
|
|
copy_gop = npo->copy + npo->copy_prod++;
|
|
copy_gop->flags = GNTCOPY_dest_gref;
|
|
copy_gop->len = bytes;
|
|
|
|
if (foreign_queue) {
|
|
copy_gop->source.domid = foreign_queue->vif->domid;
|
|
copy_gop->source.u.ref = foreign_gref;
|
|
copy_gop->flags |= GNTCOPY_source_gref;
|
|
} else {
|
|
copy_gop->source.domid = DOMID_SELF;
|
|
copy_gop->source.u.gmfn =
|
|
virt_to_mfn(page_address(page));
|
|
}
|
|
copy_gop->source.offset = offset;
|
|
|
|
copy_gop->dest.domid = queue->vif->domid;
|
|
copy_gop->dest.offset = npo->copy_off;
|
|
copy_gop->dest.u.ref = npo->copy_gref;
|
|
|
|
npo->copy_off += bytes;
|
|
meta->size += bytes;
|
|
|
|
offset += bytes;
|
|
size -= bytes;
|
|
|
|
/* Next frame */
|
|
if (offset == PAGE_SIZE && size) {
|
|
BUG_ON(!PageCompound(page));
|
|
page++;
|
|
offset = 0;
|
|
}
|
|
|
|
/* Leave a gap for the GSO descriptor. */
|
|
if (skb_is_gso(skb)) {
|
|
if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
|
|
gso_type = XEN_NETIF_GSO_TYPE_TCPV4;
|
|
else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
|
|
gso_type = XEN_NETIF_GSO_TYPE_TCPV6;
|
|
}
|
|
|
|
if (*head && ((1 << gso_type) & queue->vif->gso_mask))
|
|
queue->rx.req_cons++;
|
|
|
|
*head = 0; /* There must be something in this buffer now. */
|
|
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Find the grant ref for a given frag in a chain of struct ubuf_info's
|
|
* skb: the skb itself
|
|
* i: the frag's number
|
|
* ubuf: a pointer to an element in the chain. It should not be NULL
|
|
*
|
|
* Returns a pointer to the element in the chain where the page were found. If
|
|
* not found, returns NULL.
|
|
* See the definition of callback_struct in common.h for more details about
|
|
* the chain.
|
|
*/
|
|
static const struct ubuf_info *xenvif_find_gref(const struct sk_buff *const skb,
|
|
const int i,
|
|
const struct ubuf_info *ubuf)
|
|
{
|
|
struct xenvif_queue *foreign_queue = ubuf_to_queue(ubuf);
|
|
|
|
do {
|
|
u16 pending_idx = ubuf->desc;
|
|
|
|
if (skb_shinfo(skb)->frags[i].page.p ==
|
|
foreign_queue->mmap_pages[pending_idx])
|
|
break;
|
|
ubuf = (struct ubuf_info *) ubuf->ctx;
|
|
} while (ubuf);
|
|
|
|
return ubuf;
|
|
}
|
|
|
|
/*
|
|
* Prepare an SKB to be transmitted to the frontend.
|
|
*
|
|
* This function is responsible for allocating grant operations, meta
|
|
* structures, etc.
|
|
*
|
|
* It returns the number of meta structures consumed. The number of
|
|
* ring slots used is always equal to the number of meta slots used
|
|
* plus the number of GSO descriptors used. Currently, we use either
|
|
* zero GSO descriptors (for non-GSO packets) or one descriptor (for
|
|
* frontend-side LRO).
|
|
*/
|
|
static int xenvif_gop_skb(struct sk_buff *skb,
|
|
struct netrx_pending_operations *npo,
|
|
struct xenvif_queue *queue)
|
|
{
|
|
struct xenvif *vif = netdev_priv(skb->dev);
|
|
int nr_frags = skb_shinfo(skb)->nr_frags;
|
|
int i;
|
|
struct xen_netif_rx_request *req;
|
|
struct xenvif_rx_meta *meta;
|
|
unsigned char *data;
|
|
int head = 1;
|
|
int old_meta_prod;
|
|
int gso_type;
|
|
const struct ubuf_info *ubuf = skb_shinfo(skb)->destructor_arg;
|
|
const struct ubuf_info *const head_ubuf = ubuf;
|
|
|
|
old_meta_prod = npo->meta_prod;
|
|
|
|
gso_type = XEN_NETIF_GSO_TYPE_NONE;
|
|
if (skb_is_gso(skb)) {
|
|
if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
|
|
gso_type = XEN_NETIF_GSO_TYPE_TCPV4;
|
|
else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
|
|
gso_type = XEN_NETIF_GSO_TYPE_TCPV6;
|
|
}
|
|
|
|
/* Set up a GSO prefix descriptor, if necessary */
|
|
if ((1 << gso_type) & vif->gso_prefix_mask) {
|
|
req = RING_GET_REQUEST(&queue->rx, queue->rx.req_cons++);
|
|
meta = npo->meta + npo->meta_prod++;
|
|
meta->gso_type = gso_type;
|
|
meta->gso_size = skb_shinfo(skb)->gso_size;
|
|
meta->size = 0;
|
|
meta->id = req->id;
|
|
}
|
|
|
|
req = RING_GET_REQUEST(&queue->rx, queue->rx.req_cons++);
|
|
meta = npo->meta + npo->meta_prod++;
|
|
|
|
if ((1 << gso_type) & vif->gso_mask) {
|
|
meta->gso_type = gso_type;
|
|
meta->gso_size = skb_shinfo(skb)->gso_size;
|
|
} else {
|
|
meta->gso_type = XEN_NETIF_GSO_TYPE_NONE;
|
|
meta->gso_size = 0;
|
|
}
|
|
|
|
meta->size = 0;
|
|
meta->id = req->id;
|
|
npo->copy_off = 0;
|
|
npo->copy_gref = req->gref;
|
|
|
|
data = skb->data;
|
|
while (data < skb_tail_pointer(skb)) {
|
|
unsigned int offset = offset_in_page(data);
|
|
unsigned int len = PAGE_SIZE - offset;
|
|
|
|
if (data + len > skb_tail_pointer(skb))
|
|
len = skb_tail_pointer(skb) - data;
|
|
|
|
xenvif_gop_frag_copy(queue, skb, npo,
|
|
virt_to_page(data), len, offset, &head,
|
|
NULL,
|
|
0);
|
|
data += len;
|
|
}
|
|
|
|
for (i = 0; i < nr_frags; i++) {
|
|
/* This variable also signals whether foreign_gref has a real
|
|
* value or not.
|
|
*/
|
|
struct xenvif_queue *foreign_queue = NULL;
|
|
grant_ref_t foreign_gref;
|
|
|
|
if ((skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) &&
|
|
(ubuf->callback == &xenvif_zerocopy_callback)) {
|
|
const struct ubuf_info *const startpoint = ubuf;
|
|
|
|
/* Ideally ubuf points to the chain element which
|
|
* belongs to this frag. Or if frags were removed from
|
|
* the beginning, then shortly before it.
|
|
*/
|
|
ubuf = xenvif_find_gref(skb, i, ubuf);
|
|
|
|
/* Try again from the beginning of the list, if we
|
|
* haven't tried from there. This only makes sense in
|
|
* the unlikely event of reordering the original frags.
|
|
* For injected local pages it's an unnecessary second
|
|
* run.
|
|
*/
|
|
if (unlikely(!ubuf) && startpoint != head_ubuf)
|
|
ubuf = xenvif_find_gref(skb, i, head_ubuf);
|
|
|
|
if (likely(ubuf)) {
|
|
u16 pending_idx = ubuf->desc;
|
|
|
|
foreign_queue = ubuf_to_queue(ubuf);
|
|
foreign_gref =
|
|
foreign_queue->pending_tx_info[pending_idx].req.gref;
|
|
/* Just a safety measure. If this was the last
|
|
* element on the list, the for loop will
|
|
* iterate again if a local page were added to
|
|
* the end. Using head_ubuf here prevents the
|
|
* second search on the chain. Or the original
|
|
* frags changed order, but that's less likely.
|
|
* In any way, ubuf shouldn't be NULL.
|
|
*/
|
|
ubuf = ubuf->ctx ?
|
|
(struct ubuf_info *) ubuf->ctx :
|
|
head_ubuf;
|
|
} else
|
|
/* This frag was a local page, added to the
|
|
* array after the skb left netback.
|
|
*/
|
|
ubuf = head_ubuf;
|
|
}
|
|
xenvif_gop_frag_copy(queue, skb, npo,
|
|
skb_frag_page(&skb_shinfo(skb)->frags[i]),
|
|
skb_frag_size(&skb_shinfo(skb)->frags[i]),
|
|
skb_shinfo(skb)->frags[i].page_offset,
|
|
&head,
|
|
foreign_queue,
|
|
foreign_queue ? foreign_gref : UINT_MAX);
|
|
}
|
|
|
|
return npo->meta_prod - old_meta_prod;
|
|
}
|
|
|
|
/*
|
|
* This is a twin to xenvif_gop_skb. Assume that xenvif_gop_skb was
|
|
* used to set up the operations on the top of
|
|
* netrx_pending_operations, which have since been done. Check that
|
|
* they didn't give any errors and advance over them.
|
|
*/
|
|
static int xenvif_check_gop(struct xenvif *vif, int nr_meta_slots,
|
|
struct netrx_pending_operations *npo)
|
|
{
|
|
struct gnttab_copy *copy_op;
|
|
int status = XEN_NETIF_RSP_OKAY;
|
|
int i;
|
|
|
|
for (i = 0; i < nr_meta_slots; i++) {
|
|
copy_op = npo->copy + npo->copy_cons++;
|
|
if (copy_op->status != GNTST_okay) {
|
|
netdev_dbg(vif->dev,
|
|
"Bad status %d from copy to DOM%d.\n",
|
|
copy_op->status, vif->domid);
|
|
status = XEN_NETIF_RSP_ERROR;
|
|
}
|
|
}
|
|
|
|
return status;
|
|
}
|
|
|
|
static void xenvif_add_frag_responses(struct xenvif_queue *queue, int status,
|
|
struct xenvif_rx_meta *meta,
|
|
int nr_meta_slots)
|
|
{
|
|
int i;
|
|
unsigned long offset;
|
|
|
|
/* No fragments used */
|
|
if (nr_meta_slots <= 1)
|
|
return;
|
|
|
|
nr_meta_slots--;
|
|
|
|
for (i = 0; i < nr_meta_slots; i++) {
|
|
int flags;
|
|
if (i == nr_meta_slots - 1)
|
|
flags = 0;
|
|
else
|
|
flags = XEN_NETRXF_more_data;
|
|
|
|
offset = 0;
|
|
make_rx_response(queue, meta[i].id, status, offset,
|
|
meta[i].size, flags);
|
|
}
|
|
}
|
|
|
|
void xenvif_kick_thread(struct xenvif_queue *queue)
|
|
{
|
|
wake_up(&queue->wq);
|
|
}
|
|
|
|
static void xenvif_rx_action(struct xenvif_queue *queue)
|
|
{
|
|
s8 status;
|
|
u16 flags;
|
|
struct xen_netif_rx_response *resp;
|
|
struct sk_buff_head rxq;
|
|
struct sk_buff *skb;
|
|
LIST_HEAD(notify);
|
|
int ret;
|
|
unsigned long offset;
|
|
bool need_to_notify = false;
|
|
|
|
struct netrx_pending_operations npo = {
|
|
.copy = queue->grant_copy_op,
|
|
.meta = queue->meta,
|
|
};
|
|
|
|
skb_queue_head_init(&rxq);
|
|
|
|
while ((skb = skb_dequeue(&queue->rx_queue)) != NULL) {
|
|
RING_IDX max_slots_needed;
|
|
RING_IDX old_req_cons;
|
|
RING_IDX ring_slots_used;
|
|
int i;
|
|
|
|
/* We need a cheap worse case estimate for the number of
|
|
* slots we'll use.
|
|
*/
|
|
|
|
max_slots_needed = DIV_ROUND_UP(offset_in_page(skb->data) +
|
|
skb_headlen(skb),
|
|
PAGE_SIZE);
|
|
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
|
|
unsigned int size;
|
|
unsigned int offset;
|
|
|
|
size = skb_frag_size(&skb_shinfo(skb)->frags[i]);
|
|
offset = skb_shinfo(skb)->frags[i].page_offset;
|
|
|
|
/* For a worse-case estimate we need to factor in
|
|
* the fragment page offset as this will affect the
|
|
* number of times xenvif_gop_frag_copy() will
|
|
* call start_new_rx_buffer().
|
|
*/
|
|
max_slots_needed += DIV_ROUND_UP(offset + size,
|
|
PAGE_SIZE);
|
|
}
|
|
|
|
/* To avoid the estimate becoming too pessimal for some
|
|
* frontends that limit posted rx requests, cap the estimate
|
|
* at MAX_SKB_FRAGS. In this case netback will fully coalesce
|
|
* the skb into the provided slots.
|
|
*/
|
|
if (max_slots_needed > MAX_SKB_FRAGS) {
|
|
max_slots_needed = MAX_SKB_FRAGS;
|
|
XENVIF_RX_CB(skb)->full_coalesce = true;
|
|
} else {
|
|
XENVIF_RX_CB(skb)->full_coalesce = false;
|
|
}
|
|
|
|
/* We may need one more slot for GSO metadata */
|
|
if (skb_is_gso(skb) &&
|
|
(skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4 ||
|
|
skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6))
|
|
max_slots_needed++;
|
|
|
|
/* If the skb may not fit then bail out now */
|
|
if (!xenvif_rx_ring_slots_available(queue, max_slots_needed)) {
|
|
skb_queue_head(&queue->rx_queue, skb);
|
|
need_to_notify = true;
|
|
queue->rx_last_skb_slots = max_slots_needed;
|
|
break;
|
|
} else
|
|
queue->rx_last_skb_slots = 0;
|
|
|
|
old_req_cons = queue->rx.req_cons;
|
|
XENVIF_RX_CB(skb)->meta_slots_used = xenvif_gop_skb(skb, &npo, queue);
|
|
ring_slots_used = queue->rx.req_cons - old_req_cons;
|
|
|
|
BUG_ON(ring_slots_used > max_slots_needed);
|
|
|
|
__skb_queue_tail(&rxq, skb);
|
|
}
|
|
|
|
BUG_ON(npo.meta_prod > ARRAY_SIZE(queue->meta));
|
|
|
|
if (!npo.copy_prod)
|
|
goto done;
|
|
|
|
BUG_ON(npo.copy_prod > MAX_GRANT_COPY_OPS);
|
|
gnttab_batch_copy(queue->grant_copy_op, npo.copy_prod);
|
|
|
|
while ((skb = __skb_dequeue(&rxq)) != NULL) {
|
|
|
|
if ((1 << queue->meta[npo.meta_cons].gso_type) &
|
|
queue->vif->gso_prefix_mask) {
|
|
resp = RING_GET_RESPONSE(&queue->rx,
|
|
queue->rx.rsp_prod_pvt++);
|
|
|
|
resp->flags = XEN_NETRXF_gso_prefix | XEN_NETRXF_more_data;
|
|
|
|
resp->offset = queue->meta[npo.meta_cons].gso_size;
|
|
resp->id = queue->meta[npo.meta_cons].id;
|
|
resp->status = XENVIF_RX_CB(skb)->meta_slots_used;
|
|
|
|
npo.meta_cons++;
|
|
XENVIF_RX_CB(skb)->meta_slots_used--;
|
|
}
|
|
|
|
|
|
queue->stats.tx_bytes += skb->len;
|
|
queue->stats.tx_packets++;
|
|
|
|
status = xenvif_check_gop(queue->vif,
|
|
XENVIF_RX_CB(skb)->meta_slots_used,
|
|
&npo);
|
|
|
|
if (XENVIF_RX_CB(skb)->meta_slots_used == 1)
|
|
flags = 0;
|
|
else
|
|
flags = XEN_NETRXF_more_data;
|
|
|
|
if (skb->ip_summed == CHECKSUM_PARTIAL) /* local packet? */
|
|
flags |= XEN_NETRXF_csum_blank | XEN_NETRXF_data_validated;
|
|
else if (skb->ip_summed == CHECKSUM_UNNECESSARY)
|
|
/* remote but checksummed. */
|
|
flags |= XEN_NETRXF_data_validated;
|
|
|
|
offset = 0;
|
|
resp = make_rx_response(queue, queue->meta[npo.meta_cons].id,
|
|
status, offset,
|
|
queue->meta[npo.meta_cons].size,
|
|
flags);
|
|
|
|
if ((1 << queue->meta[npo.meta_cons].gso_type) &
|
|
queue->vif->gso_mask) {
|
|
struct xen_netif_extra_info *gso =
|
|
(struct xen_netif_extra_info *)
|
|
RING_GET_RESPONSE(&queue->rx,
|
|
queue->rx.rsp_prod_pvt++);
|
|
|
|
resp->flags |= XEN_NETRXF_extra_info;
|
|
|
|
gso->u.gso.type = queue->meta[npo.meta_cons].gso_type;
|
|
gso->u.gso.size = queue->meta[npo.meta_cons].gso_size;
|
|
gso->u.gso.pad = 0;
|
|
gso->u.gso.features = 0;
|
|
|
|
gso->type = XEN_NETIF_EXTRA_TYPE_GSO;
|
|
gso->flags = 0;
|
|
}
|
|
|
|
xenvif_add_frag_responses(queue, status,
|
|
queue->meta + npo.meta_cons + 1,
|
|
XENVIF_RX_CB(skb)->meta_slots_used);
|
|
|
|
RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&queue->rx, ret);
|
|
|
|
need_to_notify |= !!ret;
|
|
|
|
npo.meta_cons += XENVIF_RX_CB(skb)->meta_slots_used;
|
|
dev_kfree_skb(skb);
|
|
}
|
|
|
|
done:
|
|
if (need_to_notify)
|
|
notify_remote_via_irq(queue->rx_irq);
|
|
}
|
|
|
|
void xenvif_napi_schedule_or_enable_events(struct xenvif_queue *queue)
|
|
{
|
|
int more_to_do;
|
|
|
|
RING_FINAL_CHECK_FOR_REQUESTS(&queue->tx, more_to_do);
|
|
|
|
if (more_to_do)
|
|
napi_schedule(&queue->napi);
|
|
}
|
|
|
|
static void tx_add_credit(struct xenvif_queue *queue)
|
|
{
|
|
unsigned long max_burst, max_credit;
|
|
|
|
/*
|
|
* Allow a burst big enough to transmit a jumbo packet of up to 128kB.
|
|
* Otherwise the interface can seize up due to insufficient credit.
|
|
*/
|
|
max_burst = RING_GET_REQUEST(&queue->tx, queue->tx.req_cons)->size;
|
|
max_burst = min(max_burst, 131072UL);
|
|
max_burst = max(max_burst, queue->credit_bytes);
|
|
|
|
/* Take care that adding a new chunk of credit doesn't wrap to zero. */
|
|
max_credit = queue->remaining_credit + queue->credit_bytes;
|
|
if (max_credit < queue->remaining_credit)
|
|
max_credit = ULONG_MAX; /* wrapped: clamp to ULONG_MAX */
|
|
|
|
queue->remaining_credit = min(max_credit, max_burst);
|
|
}
|
|
|
|
static void tx_credit_callback(unsigned long data)
|
|
{
|
|
struct xenvif_queue *queue = (struct xenvif_queue *)data;
|
|
tx_add_credit(queue);
|
|
xenvif_napi_schedule_or_enable_events(queue);
|
|
}
|
|
|
|
static void xenvif_tx_err(struct xenvif_queue *queue,
|
|
struct xen_netif_tx_request *txp, RING_IDX end)
|
|
{
|
|
RING_IDX cons = queue->tx.req_cons;
|
|
unsigned long flags;
|
|
|
|
do {
|
|
spin_lock_irqsave(&queue->response_lock, flags);
|
|
make_tx_response(queue, txp, XEN_NETIF_RSP_ERROR);
|
|
spin_unlock_irqrestore(&queue->response_lock, flags);
|
|
if (cons == end)
|
|
break;
|
|
txp = RING_GET_REQUEST(&queue->tx, cons++);
|
|
} while (1);
|
|
queue->tx.req_cons = cons;
|
|
}
|
|
|
|
static void xenvif_fatal_tx_err(struct xenvif *vif)
|
|
{
|
|
netdev_err(vif->dev, "fatal error; disabling device\n");
|
|
vif->disabled = true;
|
|
/* Disable the vif from queue 0's kthread */
|
|
if (vif->queues)
|
|
xenvif_kick_thread(&vif->queues[0]);
|
|
}
|
|
|
|
static int xenvif_count_requests(struct xenvif_queue *queue,
|
|
struct xen_netif_tx_request *first,
|
|
struct xen_netif_tx_request *txp,
|
|
int work_to_do)
|
|
{
|
|
RING_IDX cons = queue->tx.req_cons;
|
|
int slots = 0;
|
|
int drop_err = 0;
|
|
int more_data;
|
|
|
|
if (!(first->flags & XEN_NETTXF_more_data))
|
|
return 0;
|
|
|
|
do {
|
|
struct xen_netif_tx_request dropped_tx = { 0 };
|
|
|
|
if (slots >= work_to_do) {
|
|
netdev_err(queue->vif->dev,
|
|
"Asked for %d slots but exceeds this limit\n",
|
|
work_to_do);
|
|
xenvif_fatal_tx_err(queue->vif);
|
|
return -ENODATA;
|
|
}
|
|
|
|
/* This guest is really using too many slots and
|
|
* considered malicious.
|
|
*/
|
|
if (unlikely(slots >= fatal_skb_slots)) {
|
|
netdev_err(queue->vif->dev,
|
|
"Malicious frontend using %d slots, threshold %u\n",
|
|
slots, fatal_skb_slots);
|
|
xenvif_fatal_tx_err(queue->vif);
|
|
return -E2BIG;
|
|
}
|
|
|
|
/* Xen network protocol had implicit dependency on
|
|
* MAX_SKB_FRAGS. XEN_NETBK_LEGACY_SLOTS_MAX is set to
|
|
* the historical MAX_SKB_FRAGS value 18 to honor the
|
|
* same behavior as before. Any packet using more than
|
|
* 18 slots but less than fatal_skb_slots slots is
|
|
* dropped
|
|
*/
|
|
if (!drop_err && slots >= XEN_NETBK_LEGACY_SLOTS_MAX) {
|
|
if (net_ratelimit())
|
|
netdev_dbg(queue->vif->dev,
|
|
"Too many slots (%d) exceeding limit (%d), dropping packet\n",
|
|
slots, XEN_NETBK_LEGACY_SLOTS_MAX);
|
|
drop_err = -E2BIG;
|
|
}
|
|
|
|
if (drop_err)
|
|
txp = &dropped_tx;
|
|
|
|
memcpy(txp, RING_GET_REQUEST(&queue->tx, cons + slots),
|
|
sizeof(*txp));
|
|
|
|
/* If the guest submitted a frame >= 64 KiB then
|
|
* first->size overflowed and following slots will
|
|
* appear to be larger than the frame.
|
|
*
|
|
* This cannot be fatal error as there are buggy
|
|
* frontends that do this.
|
|
*
|
|
* Consume all slots and drop the packet.
|
|
*/
|
|
if (!drop_err && txp->size > first->size) {
|
|
if (net_ratelimit())
|
|
netdev_dbg(queue->vif->dev,
|
|
"Invalid tx request, slot size %u > remaining size %u\n",
|
|
txp->size, first->size);
|
|
drop_err = -EIO;
|
|
}
|
|
|
|
first->size -= txp->size;
|
|
slots++;
|
|
|
|
if (unlikely((txp->offset + txp->size) > PAGE_SIZE)) {
|
|
netdev_err(queue->vif->dev, "Cross page boundary, txp->offset: %x, size: %u\n",
|
|
txp->offset, txp->size);
|
|
xenvif_fatal_tx_err(queue->vif);
|
|
return -EINVAL;
|
|
}
|
|
|
|
more_data = txp->flags & XEN_NETTXF_more_data;
|
|
|
|
if (!drop_err)
|
|
txp++;
|
|
|
|
} while (more_data);
|
|
|
|
if (drop_err) {
|
|
xenvif_tx_err(queue, first, cons + slots);
|
|
return drop_err;
|
|
}
|
|
|
|
return slots;
|
|
}
|
|
|
|
|
|
struct xenvif_tx_cb {
|
|
u16 pending_idx;
|
|
};
|
|
|
|
#define XENVIF_TX_CB(skb) ((struct xenvif_tx_cb *)(skb)->cb)
|
|
|
|
static inline void xenvif_tx_create_map_op(struct xenvif_queue *queue,
|
|
u16 pending_idx,
|
|
struct xen_netif_tx_request *txp,
|
|
struct gnttab_map_grant_ref *mop)
|
|
{
|
|
queue->pages_to_map[mop-queue->tx_map_ops] = queue->mmap_pages[pending_idx];
|
|
gnttab_set_map_op(mop, idx_to_kaddr(queue, pending_idx),
|
|
GNTMAP_host_map | GNTMAP_readonly,
|
|
txp->gref, queue->vif->domid);
|
|
|
|
memcpy(&queue->pending_tx_info[pending_idx].req, txp,
|
|
sizeof(*txp));
|
|
}
|
|
|
|
static inline struct sk_buff *xenvif_alloc_skb(unsigned int size)
|
|
{
|
|
struct sk_buff *skb =
|
|
alloc_skb(size + NET_SKB_PAD + NET_IP_ALIGN,
|
|
GFP_ATOMIC | __GFP_NOWARN);
|
|
if (unlikely(skb == NULL))
|
|
return NULL;
|
|
|
|
/* Packets passed to netif_rx() must have some headroom. */
|
|
skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN);
|
|
|
|
/* Initialize it here to avoid later surprises */
|
|
skb_shinfo(skb)->destructor_arg = NULL;
|
|
|
|
return skb;
|
|
}
|
|
|
|
static struct gnttab_map_grant_ref *xenvif_get_requests(struct xenvif_queue *queue,
|
|
struct sk_buff *skb,
|
|
struct xen_netif_tx_request *txp,
|
|
struct gnttab_map_grant_ref *gop)
|
|
{
|
|
struct skb_shared_info *shinfo = skb_shinfo(skb);
|
|
skb_frag_t *frags = shinfo->frags;
|
|
u16 pending_idx = XENVIF_TX_CB(skb)->pending_idx;
|
|
int start;
|
|
pending_ring_idx_t index;
|
|
unsigned int nr_slots, frag_overflow = 0;
|
|
|
|
/* At this point shinfo->nr_frags is in fact the number of
|
|
* slots, which can be as large as XEN_NETBK_LEGACY_SLOTS_MAX.
|
|
*/
|
|
if (shinfo->nr_frags > MAX_SKB_FRAGS) {
|
|
frag_overflow = shinfo->nr_frags - MAX_SKB_FRAGS;
|
|
BUG_ON(frag_overflow > MAX_SKB_FRAGS);
|
|
shinfo->nr_frags = MAX_SKB_FRAGS;
|
|
}
|
|
nr_slots = shinfo->nr_frags;
|
|
|
|
/* Skip first skb fragment if it is on same page as header fragment. */
|
|
start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx);
|
|
|
|
for (shinfo->nr_frags = start; shinfo->nr_frags < nr_slots;
|
|
shinfo->nr_frags++, txp++, gop++) {
|
|
index = pending_index(queue->pending_cons++);
|
|
pending_idx = queue->pending_ring[index];
|
|
xenvif_tx_create_map_op(queue, pending_idx, txp, gop);
|
|
frag_set_pending_idx(&frags[shinfo->nr_frags], pending_idx);
|
|
}
|
|
|
|
if (frag_overflow) {
|
|
struct sk_buff *nskb = xenvif_alloc_skb(0);
|
|
if (unlikely(nskb == NULL)) {
|
|
if (net_ratelimit())
|
|
netdev_err(queue->vif->dev,
|
|
"Can't allocate the frag_list skb.\n");
|
|
return NULL;
|
|
}
|
|
|
|
shinfo = skb_shinfo(nskb);
|
|
frags = shinfo->frags;
|
|
|
|
for (shinfo->nr_frags = 0; shinfo->nr_frags < frag_overflow;
|
|
shinfo->nr_frags++, txp++, gop++) {
|
|
index = pending_index(queue->pending_cons++);
|
|
pending_idx = queue->pending_ring[index];
|
|
xenvif_tx_create_map_op(queue, pending_idx, txp, gop);
|
|
frag_set_pending_idx(&frags[shinfo->nr_frags],
|
|
pending_idx);
|
|
}
|
|
|
|
skb_shinfo(skb)->frag_list = nskb;
|
|
}
|
|
|
|
return gop;
|
|
}
|
|
|
|
static inline void xenvif_grant_handle_set(struct xenvif_queue *queue,
|
|
u16 pending_idx,
|
|
grant_handle_t handle)
|
|
{
|
|
if (unlikely(queue->grant_tx_handle[pending_idx] !=
|
|
NETBACK_INVALID_HANDLE)) {
|
|
netdev_err(queue->vif->dev,
|
|
"Trying to overwrite active handle! pending_idx: %x\n",
|
|
pending_idx);
|
|
BUG();
|
|
}
|
|
queue->grant_tx_handle[pending_idx] = handle;
|
|
}
|
|
|
|
static inline void xenvif_grant_handle_reset(struct xenvif_queue *queue,
|
|
u16 pending_idx)
|
|
{
|
|
if (unlikely(queue->grant_tx_handle[pending_idx] ==
|
|
NETBACK_INVALID_HANDLE)) {
|
|
netdev_err(queue->vif->dev,
|
|
"Trying to unmap invalid handle! pending_idx: %x\n",
|
|
pending_idx);
|
|
BUG();
|
|
}
|
|
queue->grant_tx_handle[pending_idx] = NETBACK_INVALID_HANDLE;
|
|
}
|
|
|
|
static int xenvif_tx_check_gop(struct xenvif_queue *queue,
|
|
struct sk_buff *skb,
|
|
struct gnttab_map_grant_ref **gopp_map,
|
|
struct gnttab_copy **gopp_copy)
|
|
{
|
|
struct gnttab_map_grant_ref *gop_map = *gopp_map;
|
|
u16 pending_idx = XENVIF_TX_CB(skb)->pending_idx;
|
|
/* This always points to the shinfo of the skb being checked, which
|
|
* could be either the first or the one on the frag_list
|
|
*/
|
|
struct skb_shared_info *shinfo = skb_shinfo(skb);
|
|
/* If this is non-NULL, we are currently checking the frag_list skb, and
|
|
* this points to the shinfo of the first one
|
|
*/
|
|
struct skb_shared_info *first_shinfo = NULL;
|
|
int nr_frags = shinfo->nr_frags;
|
|
const bool sharedslot = nr_frags &&
|
|
frag_get_pending_idx(&shinfo->frags[0]) == pending_idx;
|
|
int i, err;
|
|
|
|
/* Check status of header. */
|
|
err = (*gopp_copy)->status;
|
|
if (unlikely(err)) {
|
|
if (net_ratelimit())
|
|
netdev_dbg(queue->vif->dev,
|
|
"Grant copy of header failed! status: %d pending_idx: %u ref: %u\n",
|
|
(*gopp_copy)->status,
|
|
pending_idx,
|
|
(*gopp_copy)->source.u.ref);
|
|
/* The first frag might still have this slot mapped */
|
|
if (!sharedslot)
|
|
xenvif_idx_release(queue, pending_idx,
|
|
XEN_NETIF_RSP_ERROR);
|
|
}
|
|
(*gopp_copy)++;
|
|
|
|
check_frags:
|
|
for (i = 0; i < nr_frags; i++, gop_map++) {
|
|
int j, newerr;
|
|
|
|
pending_idx = frag_get_pending_idx(&shinfo->frags[i]);
|
|
|
|
/* Check error status: if okay then remember grant handle. */
|
|
newerr = gop_map->status;
|
|
|
|
if (likely(!newerr)) {
|
|
xenvif_grant_handle_set(queue,
|
|
pending_idx,
|
|
gop_map->handle);
|
|
/* Had a previous error? Invalidate this fragment. */
|
|
if (unlikely(err)) {
|
|
xenvif_idx_unmap(queue, pending_idx);
|
|
/* If the mapping of the first frag was OK, but
|
|
* the header's copy failed, and they are
|
|
* sharing a slot, send an error
|
|
*/
|
|
if (i == 0 && sharedslot)
|
|
xenvif_idx_release(queue, pending_idx,
|
|
XEN_NETIF_RSP_ERROR);
|
|
else
|
|
xenvif_idx_release(queue, pending_idx,
|
|
XEN_NETIF_RSP_OKAY);
|
|
}
|
|
continue;
|
|
}
|
|
|
|
/* Error on this fragment: respond to client with an error. */
|
|
if (net_ratelimit())
|
|
netdev_dbg(queue->vif->dev,
|
|
"Grant map of %d. frag failed! status: %d pending_idx: %u ref: %u\n",
|
|
i,
|
|
gop_map->status,
|
|
pending_idx,
|
|
gop_map->ref);
|
|
|
|
xenvif_idx_release(queue, pending_idx, XEN_NETIF_RSP_ERROR);
|
|
|
|
/* Not the first error? Preceding frags already invalidated. */
|
|
if (err)
|
|
continue;
|
|
|
|
/* First error: if the header haven't shared a slot with the
|
|
* first frag, release it as well.
|
|
*/
|
|
if (!sharedslot)
|
|
xenvif_idx_release(queue,
|
|
XENVIF_TX_CB(skb)->pending_idx,
|
|
XEN_NETIF_RSP_OKAY);
|
|
|
|
/* Invalidate preceding fragments of this skb. */
|
|
for (j = 0; j < i; j++) {
|
|
pending_idx = frag_get_pending_idx(&shinfo->frags[j]);
|
|
xenvif_idx_unmap(queue, pending_idx);
|
|
xenvif_idx_release(queue, pending_idx,
|
|
XEN_NETIF_RSP_OKAY);
|
|
}
|
|
|
|
/* And if we found the error while checking the frag_list, unmap
|
|
* the first skb's frags
|
|
*/
|
|
if (first_shinfo) {
|
|
for (j = 0; j < first_shinfo->nr_frags; j++) {
|
|
pending_idx = frag_get_pending_idx(&first_shinfo->frags[j]);
|
|
xenvif_idx_unmap(queue, pending_idx);
|
|
xenvif_idx_release(queue, pending_idx,
|
|
XEN_NETIF_RSP_OKAY);
|
|
}
|
|
}
|
|
|
|
/* Remember the error: invalidate all subsequent fragments. */
|
|
err = newerr;
|
|
}
|
|
|
|
if (skb_has_frag_list(skb) && !first_shinfo) {
|
|
first_shinfo = skb_shinfo(skb);
|
|
shinfo = skb_shinfo(skb_shinfo(skb)->frag_list);
|
|
nr_frags = shinfo->nr_frags;
|
|
|
|
goto check_frags;
|
|
}
|
|
|
|
*gopp_map = gop_map;
|
|
return err;
|
|
}
|
|
|
|
static void xenvif_fill_frags(struct xenvif_queue *queue, struct sk_buff *skb)
|
|
{
|
|
struct skb_shared_info *shinfo = skb_shinfo(skb);
|
|
int nr_frags = shinfo->nr_frags;
|
|
int i;
|
|
u16 prev_pending_idx = INVALID_PENDING_IDX;
|
|
|
|
for (i = 0; i < nr_frags; i++) {
|
|
skb_frag_t *frag = shinfo->frags + i;
|
|
struct xen_netif_tx_request *txp;
|
|
struct page *page;
|
|
u16 pending_idx;
|
|
|
|
pending_idx = frag_get_pending_idx(frag);
|
|
|
|
/* If this is not the first frag, chain it to the previous*/
|
|
if (prev_pending_idx == INVALID_PENDING_IDX)
|
|
skb_shinfo(skb)->destructor_arg =
|
|
&callback_param(queue, pending_idx);
|
|
else
|
|
callback_param(queue, prev_pending_idx).ctx =
|
|
&callback_param(queue, pending_idx);
|
|
|
|
callback_param(queue, pending_idx).ctx = NULL;
|
|
prev_pending_idx = pending_idx;
|
|
|
|
txp = &queue->pending_tx_info[pending_idx].req;
|
|
page = virt_to_page(idx_to_kaddr(queue, pending_idx));
|
|
__skb_fill_page_desc(skb, i, page, txp->offset, txp->size);
|
|
skb->len += txp->size;
|
|
skb->data_len += txp->size;
|
|
skb->truesize += txp->size;
|
|
|
|
/* Take an extra reference to offset network stack's put_page */
|
|
get_page(queue->mmap_pages[pending_idx]);
|
|
}
|
|
/* FIXME: __skb_fill_page_desc set this to true because page->pfmemalloc
|
|
* overlaps with "index", and "mapping" is not set. I think mapping
|
|
* should be set. If delivered to local stack, it would drop this
|
|
* skb in sk_filter unless the socket has the right to use it.
|
|
*/
|
|
skb->pfmemalloc = false;
|
|
}
|
|
|
|
static int xenvif_get_extras(struct xenvif_queue *queue,
|
|
struct xen_netif_extra_info *extras,
|
|
int work_to_do)
|
|
{
|
|
struct xen_netif_extra_info extra;
|
|
RING_IDX cons = queue->tx.req_cons;
|
|
|
|
do {
|
|
if (unlikely(work_to_do-- <= 0)) {
|
|
netdev_err(queue->vif->dev, "Missing extra info\n");
|
|
xenvif_fatal_tx_err(queue->vif);
|
|
return -EBADR;
|
|
}
|
|
|
|
memcpy(&extra, RING_GET_REQUEST(&queue->tx, cons),
|
|
sizeof(extra));
|
|
if (unlikely(!extra.type ||
|
|
extra.type >= XEN_NETIF_EXTRA_TYPE_MAX)) {
|
|
queue->tx.req_cons = ++cons;
|
|
netdev_err(queue->vif->dev,
|
|
"Invalid extra type: %d\n", extra.type);
|
|
xenvif_fatal_tx_err(queue->vif);
|
|
return -EINVAL;
|
|
}
|
|
|
|
memcpy(&extras[extra.type - 1], &extra, sizeof(extra));
|
|
queue->tx.req_cons = ++cons;
|
|
} while (extra.flags & XEN_NETIF_EXTRA_FLAG_MORE);
|
|
|
|
return work_to_do;
|
|
}
|
|
|
|
static int xenvif_set_skb_gso(struct xenvif *vif,
|
|
struct sk_buff *skb,
|
|
struct xen_netif_extra_info *gso)
|
|
{
|
|
if (!gso->u.gso.size) {
|
|
netdev_err(vif->dev, "GSO size must not be zero.\n");
|
|
xenvif_fatal_tx_err(vif);
|
|
return -EINVAL;
|
|
}
|
|
|
|
switch (gso->u.gso.type) {
|
|
case XEN_NETIF_GSO_TYPE_TCPV4:
|
|
skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
|
|
break;
|
|
case XEN_NETIF_GSO_TYPE_TCPV6:
|
|
skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
|
|
break;
|
|
default:
|
|
netdev_err(vif->dev, "Bad GSO type %d.\n", gso->u.gso.type);
|
|
xenvif_fatal_tx_err(vif);
|
|
return -EINVAL;
|
|
}
|
|
|
|
skb_shinfo(skb)->gso_size = gso->u.gso.size;
|
|
/* gso_segs will be calculated later */
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int checksum_setup(struct xenvif_queue *queue, struct sk_buff *skb)
|
|
{
|
|
bool recalculate_partial_csum = false;
|
|
|
|
/* A GSO SKB must be CHECKSUM_PARTIAL. However some buggy
|
|
* peers can fail to set NETRXF_csum_blank when sending a GSO
|
|
* frame. In this case force the SKB to CHECKSUM_PARTIAL and
|
|
* recalculate the partial checksum.
|
|
*/
|
|
if (skb->ip_summed != CHECKSUM_PARTIAL && skb_is_gso(skb)) {
|
|
queue->stats.rx_gso_checksum_fixup++;
|
|
skb->ip_summed = CHECKSUM_PARTIAL;
|
|
recalculate_partial_csum = true;
|
|
}
|
|
|
|
/* A non-CHECKSUM_PARTIAL SKB does not require setup. */
|
|
if (skb->ip_summed != CHECKSUM_PARTIAL)
|
|
return 0;
|
|
|
|
return skb_checksum_setup(skb, recalculate_partial_csum);
|
|
}
|
|
|
|
static bool tx_credit_exceeded(struct xenvif_queue *queue, unsigned size)
|
|
{
|
|
u64 now = get_jiffies_64();
|
|
u64 next_credit = queue->credit_window_start +
|
|
msecs_to_jiffies(queue->credit_usec / 1000);
|
|
|
|
/* Timer could already be pending in rare cases. */
|
|
if (timer_pending(&queue->credit_timeout))
|
|
return true;
|
|
|
|
/* Passed the point where we can replenish credit? */
|
|
if (time_after_eq64(now, next_credit)) {
|
|
queue->credit_window_start = now;
|
|
tx_add_credit(queue);
|
|
}
|
|
|
|
/* Still too big to send right now? Set a callback. */
|
|
if (size > queue->remaining_credit) {
|
|
queue->credit_timeout.data =
|
|
(unsigned long)queue;
|
|
queue->credit_timeout.function =
|
|
tx_credit_callback;
|
|
mod_timer(&queue->credit_timeout,
|
|
next_credit);
|
|
queue->credit_window_start = next_credit;
|
|
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static void xenvif_tx_build_gops(struct xenvif_queue *queue,
|
|
int budget,
|
|
unsigned *copy_ops,
|
|
unsigned *map_ops)
|
|
{
|
|
struct gnttab_map_grant_ref *gop = queue->tx_map_ops, *request_gop;
|
|
struct sk_buff *skb;
|
|
int ret;
|
|
|
|
while (skb_queue_len(&queue->tx_queue) < budget) {
|
|
struct xen_netif_tx_request txreq;
|
|
struct xen_netif_tx_request txfrags[XEN_NETBK_LEGACY_SLOTS_MAX];
|
|
struct xen_netif_extra_info extras[XEN_NETIF_EXTRA_TYPE_MAX-1];
|
|
u16 pending_idx;
|
|
RING_IDX idx;
|
|
int work_to_do;
|
|
unsigned int data_len;
|
|
pending_ring_idx_t index;
|
|
|
|
if (queue->tx.sring->req_prod - queue->tx.req_cons >
|
|
XEN_NETIF_TX_RING_SIZE) {
|
|
netdev_err(queue->vif->dev,
|
|
"Impossible number of requests. "
|
|
"req_prod %d, req_cons %d, size %ld\n",
|
|
queue->tx.sring->req_prod, queue->tx.req_cons,
|
|
XEN_NETIF_TX_RING_SIZE);
|
|
xenvif_fatal_tx_err(queue->vif);
|
|
break;
|
|
}
|
|
|
|
work_to_do = RING_HAS_UNCONSUMED_REQUESTS(&queue->tx);
|
|
if (!work_to_do)
|
|
break;
|
|
|
|
idx = queue->tx.req_cons;
|
|
rmb(); /* Ensure that we see the request before we copy it. */
|
|
memcpy(&txreq, RING_GET_REQUEST(&queue->tx, idx), sizeof(txreq));
|
|
|
|
/* Credit-based scheduling. */
|
|
if (txreq.size > queue->remaining_credit &&
|
|
tx_credit_exceeded(queue, txreq.size))
|
|
break;
|
|
|
|
queue->remaining_credit -= txreq.size;
|
|
|
|
work_to_do--;
|
|
queue->tx.req_cons = ++idx;
|
|
|
|
memset(extras, 0, sizeof(extras));
|
|
if (txreq.flags & XEN_NETTXF_extra_info) {
|
|
work_to_do = xenvif_get_extras(queue, extras,
|
|
work_to_do);
|
|
idx = queue->tx.req_cons;
|
|
if (unlikely(work_to_do < 0))
|
|
break;
|
|
}
|
|
|
|
ret = xenvif_count_requests(queue, &txreq, txfrags, work_to_do);
|
|
if (unlikely(ret < 0))
|
|
break;
|
|
|
|
idx += ret;
|
|
|
|
if (unlikely(txreq.size < ETH_HLEN)) {
|
|
netdev_dbg(queue->vif->dev,
|
|
"Bad packet size: %d\n", txreq.size);
|
|
xenvif_tx_err(queue, &txreq, idx);
|
|
break;
|
|
}
|
|
|
|
/* No crossing a page as the payload mustn't fragment. */
|
|
if (unlikely((txreq.offset + txreq.size) > PAGE_SIZE)) {
|
|
netdev_err(queue->vif->dev,
|
|
"txreq.offset: %x, size: %u, end: %lu\n",
|
|
txreq.offset, txreq.size,
|
|
(txreq.offset&~PAGE_MASK) + txreq.size);
|
|
xenvif_fatal_tx_err(queue->vif);
|
|
break;
|
|
}
|
|
|
|
index = pending_index(queue->pending_cons);
|
|
pending_idx = queue->pending_ring[index];
|
|
|
|
data_len = (txreq.size > PKT_PROT_LEN &&
|
|
ret < XEN_NETBK_LEGACY_SLOTS_MAX) ?
|
|
PKT_PROT_LEN : txreq.size;
|
|
|
|
skb = xenvif_alloc_skb(data_len);
|
|
if (unlikely(skb == NULL)) {
|
|
netdev_dbg(queue->vif->dev,
|
|
"Can't allocate a skb in start_xmit.\n");
|
|
xenvif_tx_err(queue, &txreq, idx);
|
|
break;
|
|
}
|
|
|
|
if (extras[XEN_NETIF_EXTRA_TYPE_GSO - 1].type) {
|
|
struct xen_netif_extra_info *gso;
|
|
gso = &extras[XEN_NETIF_EXTRA_TYPE_GSO - 1];
|
|
|
|
if (xenvif_set_skb_gso(queue->vif, skb, gso)) {
|
|
/* Failure in xenvif_set_skb_gso is fatal. */
|
|
kfree_skb(skb);
|
|
break;
|
|
}
|
|
}
|
|
|
|
XENVIF_TX_CB(skb)->pending_idx = pending_idx;
|
|
|
|
__skb_put(skb, data_len);
|
|
queue->tx_copy_ops[*copy_ops].source.u.ref = txreq.gref;
|
|
queue->tx_copy_ops[*copy_ops].source.domid = queue->vif->domid;
|
|
queue->tx_copy_ops[*copy_ops].source.offset = txreq.offset;
|
|
|
|
queue->tx_copy_ops[*copy_ops].dest.u.gmfn =
|
|
virt_to_mfn(skb->data);
|
|
queue->tx_copy_ops[*copy_ops].dest.domid = DOMID_SELF;
|
|
queue->tx_copy_ops[*copy_ops].dest.offset =
|
|
offset_in_page(skb->data);
|
|
|
|
queue->tx_copy_ops[*copy_ops].len = data_len;
|
|
queue->tx_copy_ops[*copy_ops].flags = GNTCOPY_source_gref;
|
|
|
|
(*copy_ops)++;
|
|
|
|
skb_shinfo(skb)->nr_frags = ret;
|
|
if (data_len < txreq.size) {
|
|
skb_shinfo(skb)->nr_frags++;
|
|
frag_set_pending_idx(&skb_shinfo(skb)->frags[0],
|
|
pending_idx);
|
|
xenvif_tx_create_map_op(queue, pending_idx, &txreq, gop);
|
|
gop++;
|
|
} else {
|
|
frag_set_pending_idx(&skb_shinfo(skb)->frags[0],
|
|
INVALID_PENDING_IDX);
|
|
memcpy(&queue->pending_tx_info[pending_idx].req, &txreq,
|
|
sizeof(txreq));
|
|
}
|
|
|
|
queue->pending_cons++;
|
|
|
|
request_gop = xenvif_get_requests(queue, skb, txfrags, gop);
|
|
if (request_gop == NULL) {
|
|
kfree_skb(skb);
|
|
xenvif_tx_err(queue, &txreq, idx);
|
|
break;
|
|
}
|
|
gop = request_gop;
|
|
|
|
__skb_queue_tail(&queue->tx_queue, skb);
|
|
|
|
queue->tx.req_cons = idx;
|
|
|
|
if (((gop-queue->tx_map_ops) >= ARRAY_SIZE(queue->tx_map_ops)) ||
|
|
(*copy_ops >= ARRAY_SIZE(queue->tx_copy_ops)))
|
|
break;
|
|
}
|
|
|
|
(*map_ops) = gop - queue->tx_map_ops;
|
|
return;
|
|
}
|
|
|
|
/* Consolidate skb with a frag_list into a brand new one with local pages on
|
|
* frags. Returns 0 or -ENOMEM if can't allocate new pages.
|
|
*/
|
|
static int xenvif_handle_frag_list(struct xenvif_queue *queue, struct sk_buff *skb)
|
|
{
|
|
unsigned int offset = skb_headlen(skb);
|
|
skb_frag_t frags[MAX_SKB_FRAGS];
|
|
int i;
|
|
struct ubuf_info *uarg;
|
|
struct sk_buff *nskb = skb_shinfo(skb)->frag_list;
|
|
|
|
queue->stats.tx_zerocopy_sent += 2;
|
|
queue->stats.tx_frag_overflow++;
|
|
|
|
xenvif_fill_frags(queue, nskb);
|
|
/* Subtract frags size, we will correct it later */
|
|
skb->truesize -= skb->data_len;
|
|
skb->len += nskb->len;
|
|
skb->data_len += nskb->len;
|
|
|
|
/* create a brand new frags array and coalesce there */
|
|
for (i = 0; offset < skb->len; i++) {
|
|
struct page *page;
|
|
unsigned int len;
|
|
|
|
BUG_ON(i >= MAX_SKB_FRAGS);
|
|
page = alloc_page(GFP_ATOMIC|__GFP_COLD);
|
|
if (!page) {
|
|
int j;
|
|
skb->truesize += skb->data_len;
|
|
for (j = 0; j < i; j++)
|
|
put_page(frags[j].page.p);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
if (offset + PAGE_SIZE < skb->len)
|
|
len = PAGE_SIZE;
|
|
else
|
|
len = skb->len - offset;
|
|
if (skb_copy_bits(skb, offset, page_address(page), len))
|
|
BUG();
|
|
|
|
offset += len;
|
|
frags[i].page.p = page;
|
|
frags[i].page_offset = 0;
|
|
skb_frag_size_set(&frags[i], len);
|
|
}
|
|
/* swap out with old one */
|
|
memcpy(skb_shinfo(skb)->frags,
|
|
frags,
|
|
i * sizeof(skb_frag_t));
|
|
skb_shinfo(skb)->nr_frags = i;
|
|
skb->truesize += i * PAGE_SIZE;
|
|
|
|
/* remove traces of mapped pages and frag_list */
|
|
skb_frag_list_init(skb);
|
|
uarg = skb_shinfo(skb)->destructor_arg;
|
|
/* increase inflight counter to offset decrement in callback */
|
|
atomic_inc(&queue->inflight_packets);
|
|
uarg->callback(uarg, true);
|
|
skb_shinfo(skb)->destructor_arg = NULL;
|
|
|
|
xenvif_skb_zerocopy_prepare(queue, nskb);
|
|
kfree_skb(nskb);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int xenvif_tx_submit(struct xenvif_queue *queue)
|
|
{
|
|
struct gnttab_map_grant_ref *gop_map = queue->tx_map_ops;
|
|
struct gnttab_copy *gop_copy = queue->tx_copy_ops;
|
|
struct sk_buff *skb;
|
|
int work_done = 0;
|
|
|
|
while ((skb = __skb_dequeue(&queue->tx_queue)) != NULL) {
|
|
struct xen_netif_tx_request *txp;
|
|
u16 pending_idx;
|
|
unsigned data_len;
|
|
|
|
pending_idx = XENVIF_TX_CB(skb)->pending_idx;
|
|
txp = &queue->pending_tx_info[pending_idx].req;
|
|
|
|
/* Check the remap error code. */
|
|
if (unlikely(xenvif_tx_check_gop(queue, skb, &gop_map, &gop_copy))) {
|
|
/* If there was an error, xenvif_tx_check_gop is
|
|
* expected to release all the frags which were mapped,
|
|
* so kfree_skb shouldn't do it again
|
|
*/
|
|
skb_shinfo(skb)->nr_frags = 0;
|
|
if (skb_has_frag_list(skb)) {
|
|
struct sk_buff *nskb =
|
|
skb_shinfo(skb)->frag_list;
|
|
skb_shinfo(nskb)->nr_frags = 0;
|
|
}
|
|
kfree_skb(skb);
|
|
continue;
|
|
}
|
|
|
|
data_len = skb->len;
|
|
callback_param(queue, pending_idx).ctx = NULL;
|
|
if (data_len < txp->size) {
|
|
/* Append the packet payload as a fragment. */
|
|
txp->offset += data_len;
|
|
txp->size -= data_len;
|
|
} else {
|
|
/* Schedule a response immediately. */
|
|
xenvif_idx_release(queue, pending_idx,
|
|
XEN_NETIF_RSP_OKAY);
|
|
}
|
|
|
|
if (txp->flags & XEN_NETTXF_csum_blank)
|
|
skb->ip_summed = CHECKSUM_PARTIAL;
|
|
else if (txp->flags & XEN_NETTXF_data_validated)
|
|
skb->ip_summed = CHECKSUM_UNNECESSARY;
|
|
|
|
xenvif_fill_frags(queue, skb);
|
|
|
|
if (unlikely(skb_has_frag_list(skb))) {
|
|
if (xenvif_handle_frag_list(queue, skb)) {
|
|
if (net_ratelimit())
|
|
netdev_err(queue->vif->dev,
|
|
"Not enough memory to consolidate frag_list!\n");
|
|
xenvif_skb_zerocopy_prepare(queue, skb);
|
|
kfree_skb(skb);
|
|
continue;
|
|
}
|
|
}
|
|
|
|
if (skb_is_nonlinear(skb) && skb_headlen(skb) < PKT_PROT_LEN) {
|
|
int target = min_t(int, skb->len, PKT_PROT_LEN);
|
|
__pskb_pull_tail(skb, target - skb_headlen(skb));
|
|
}
|
|
|
|
skb->dev = queue->vif->dev;
|
|
skb->protocol = eth_type_trans(skb, skb->dev);
|
|
skb_reset_network_header(skb);
|
|
|
|
if (checksum_setup(queue, skb)) {
|
|
netdev_dbg(queue->vif->dev,
|
|
"Can't setup checksum in net_tx_action\n");
|
|
/* We have to set this flag to trigger the callback */
|
|
if (skb_shinfo(skb)->destructor_arg)
|
|
xenvif_skb_zerocopy_prepare(queue, skb);
|
|
kfree_skb(skb);
|
|
continue;
|
|
}
|
|
|
|
skb_probe_transport_header(skb, 0);
|
|
|
|
/* If the packet is GSO then we will have just set up the
|
|
* transport header offset in checksum_setup so it's now
|
|
* straightforward to calculate gso_segs.
|
|
*/
|
|
if (skb_is_gso(skb)) {
|
|
int mss = skb_shinfo(skb)->gso_size;
|
|
int hdrlen = skb_transport_header(skb) -
|
|
skb_mac_header(skb) +
|
|
tcp_hdrlen(skb);
|
|
|
|
skb_shinfo(skb)->gso_segs =
|
|
DIV_ROUND_UP(skb->len - hdrlen, mss);
|
|
}
|
|
|
|
queue->stats.rx_bytes += skb->len;
|
|
queue->stats.rx_packets++;
|
|
|
|
work_done++;
|
|
|
|
/* Set this flag right before netif_receive_skb, otherwise
|
|
* someone might think this packet already left netback, and
|
|
* do a skb_copy_ubufs while we are still in control of the
|
|
* skb. E.g. the __pskb_pull_tail earlier can do such thing.
|
|
*/
|
|
if (skb_shinfo(skb)->destructor_arg) {
|
|
xenvif_skb_zerocopy_prepare(queue, skb);
|
|
queue->stats.tx_zerocopy_sent++;
|
|
}
|
|
|
|
netif_receive_skb(skb);
|
|
}
|
|
|
|
return work_done;
|
|
}
|
|
|
|
void xenvif_zerocopy_callback(struct ubuf_info *ubuf, bool zerocopy_success)
|
|
{
|
|
unsigned long flags;
|
|
pending_ring_idx_t index;
|
|
struct xenvif_queue *queue = ubuf_to_queue(ubuf);
|
|
|
|
/* This is the only place where we grab this lock, to protect callbacks
|
|
* from each other.
|
|
*/
|
|
spin_lock_irqsave(&queue->callback_lock, flags);
|
|
do {
|
|
u16 pending_idx = ubuf->desc;
|
|
ubuf = (struct ubuf_info *) ubuf->ctx;
|
|
BUG_ON(queue->dealloc_prod - queue->dealloc_cons >=
|
|
MAX_PENDING_REQS);
|
|
index = pending_index(queue->dealloc_prod);
|
|
queue->dealloc_ring[index] = pending_idx;
|
|
/* Sync with xenvif_tx_dealloc_action:
|
|
* insert idx then incr producer.
|
|
*/
|
|
smp_wmb();
|
|
queue->dealloc_prod++;
|
|
} while (ubuf);
|
|
wake_up(&queue->dealloc_wq);
|
|
spin_unlock_irqrestore(&queue->callback_lock, flags);
|
|
|
|
if (likely(zerocopy_success))
|
|
queue->stats.tx_zerocopy_success++;
|
|
else
|
|
queue->stats.tx_zerocopy_fail++;
|
|
xenvif_skb_zerocopy_complete(queue);
|
|
}
|
|
|
|
static inline void xenvif_tx_dealloc_action(struct xenvif_queue *queue)
|
|
{
|
|
struct gnttab_unmap_grant_ref *gop;
|
|
pending_ring_idx_t dc, dp;
|
|
u16 pending_idx, pending_idx_release[MAX_PENDING_REQS];
|
|
unsigned int i = 0;
|
|
|
|
dc = queue->dealloc_cons;
|
|
gop = queue->tx_unmap_ops;
|
|
|
|
/* Free up any grants we have finished using */
|
|
do {
|
|
dp = queue->dealloc_prod;
|
|
|
|
/* Ensure we see all indices enqueued by all
|
|
* xenvif_zerocopy_callback().
|
|
*/
|
|
smp_rmb();
|
|
|
|
while (dc != dp) {
|
|
BUG_ON(gop - queue->tx_unmap_ops > MAX_PENDING_REQS);
|
|
pending_idx =
|
|
queue->dealloc_ring[pending_index(dc++)];
|
|
|
|
pending_idx_release[gop-queue->tx_unmap_ops] =
|
|
pending_idx;
|
|
queue->pages_to_unmap[gop-queue->tx_unmap_ops] =
|
|
queue->mmap_pages[pending_idx];
|
|
gnttab_set_unmap_op(gop,
|
|
idx_to_kaddr(queue, pending_idx),
|
|
GNTMAP_host_map,
|
|
queue->grant_tx_handle[pending_idx]);
|
|
xenvif_grant_handle_reset(queue, pending_idx);
|
|
++gop;
|
|
}
|
|
|
|
} while (dp != queue->dealloc_prod);
|
|
|
|
queue->dealloc_cons = dc;
|
|
|
|
if (gop - queue->tx_unmap_ops > 0) {
|
|
int ret;
|
|
ret = gnttab_unmap_refs(queue->tx_unmap_ops,
|
|
NULL,
|
|
queue->pages_to_unmap,
|
|
gop - queue->tx_unmap_ops);
|
|
if (ret) {
|
|
netdev_err(queue->vif->dev, "Unmap fail: nr_ops %tx ret %d\n",
|
|
gop - queue->tx_unmap_ops, ret);
|
|
for (i = 0; i < gop - queue->tx_unmap_ops; ++i) {
|
|
if (gop[i].status != GNTST_okay)
|
|
netdev_err(queue->vif->dev,
|
|
" host_addr: %llx handle: %x status: %d\n",
|
|
gop[i].host_addr,
|
|
gop[i].handle,
|
|
gop[i].status);
|
|
}
|
|
BUG();
|
|
}
|
|
}
|
|
|
|
for (i = 0; i < gop - queue->tx_unmap_ops; ++i)
|
|
xenvif_idx_release(queue, pending_idx_release[i],
|
|
XEN_NETIF_RSP_OKAY);
|
|
}
|
|
|
|
|
|
/* Called after netfront has transmitted */
|
|
int xenvif_tx_action(struct xenvif_queue *queue, int budget)
|
|
{
|
|
unsigned nr_mops, nr_cops = 0;
|
|
int work_done, ret;
|
|
|
|
if (unlikely(!tx_work_todo(queue)))
|
|
return 0;
|
|
|
|
xenvif_tx_build_gops(queue, budget, &nr_cops, &nr_mops);
|
|
|
|
if (nr_cops == 0)
|
|
return 0;
|
|
|
|
gnttab_batch_copy(queue->tx_copy_ops, nr_cops);
|
|
if (nr_mops != 0) {
|
|
ret = gnttab_map_refs(queue->tx_map_ops,
|
|
NULL,
|
|
queue->pages_to_map,
|
|
nr_mops);
|
|
BUG_ON(ret);
|
|
}
|
|
|
|
work_done = xenvif_tx_submit(queue);
|
|
|
|
return work_done;
|
|
}
|
|
|
|
static void xenvif_idx_release(struct xenvif_queue *queue, u16 pending_idx,
|
|
u8 status)
|
|
{
|
|
struct pending_tx_info *pending_tx_info;
|
|
pending_ring_idx_t index;
|
|
unsigned long flags;
|
|
|
|
pending_tx_info = &queue->pending_tx_info[pending_idx];
|
|
spin_lock_irqsave(&queue->response_lock, flags);
|
|
make_tx_response(queue, &pending_tx_info->req, status);
|
|
index = pending_index(queue->pending_prod);
|
|
queue->pending_ring[index] = pending_idx;
|
|
/* TX shouldn't use the index before we give it back here */
|
|
mb();
|
|
queue->pending_prod++;
|
|
spin_unlock_irqrestore(&queue->response_lock, flags);
|
|
}
|
|
|
|
|
|
static void make_tx_response(struct xenvif_queue *queue,
|
|
struct xen_netif_tx_request *txp,
|
|
s8 st)
|
|
{
|
|
RING_IDX i = queue->tx.rsp_prod_pvt;
|
|
struct xen_netif_tx_response *resp;
|
|
int notify;
|
|
|
|
resp = RING_GET_RESPONSE(&queue->tx, i);
|
|
resp->id = txp->id;
|
|
resp->status = st;
|
|
|
|
if (txp->flags & XEN_NETTXF_extra_info)
|
|
RING_GET_RESPONSE(&queue->tx, ++i)->status = XEN_NETIF_RSP_NULL;
|
|
|
|
queue->tx.rsp_prod_pvt = ++i;
|
|
RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&queue->tx, notify);
|
|
if (notify)
|
|
notify_remote_via_irq(queue->tx_irq);
|
|
}
|
|
|
|
static struct xen_netif_rx_response *make_rx_response(struct xenvif_queue *queue,
|
|
u16 id,
|
|
s8 st,
|
|
u16 offset,
|
|
u16 size,
|
|
u16 flags)
|
|
{
|
|
RING_IDX i = queue->rx.rsp_prod_pvt;
|
|
struct xen_netif_rx_response *resp;
|
|
|
|
resp = RING_GET_RESPONSE(&queue->rx, i);
|
|
resp->offset = offset;
|
|
resp->flags = flags;
|
|
resp->id = id;
|
|
resp->status = (s16)size;
|
|
if (st < 0)
|
|
resp->status = (s16)st;
|
|
|
|
queue->rx.rsp_prod_pvt = ++i;
|
|
|
|
return resp;
|
|
}
|
|
|
|
void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx)
|
|
{
|
|
int ret;
|
|
struct gnttab_unmap_grant_ref tx_unmap_op;
|
|
|
|
gnttab_set_unmap_op(&tx_unmap_op,
|
|
idx_to_kaddr(queue, pending_idx),
|
|
GNTMAP_host_map,
|
|
queue->grant_tx_handle[pending_idx]);
|
|
xenvif_grant_handle_reset(queue, pending_idx);
|
|
|
|
ret = gnttab_unmap_refs(&tx_unmap_op, NULL,
|
|
&queue->mmap_pages[pending_idx], 1);
|
|
if (ret) {
|
|
netdev_err(queue->vif->dev,
|
|
"Unmap fail: ret: %d pending_idx: %d host_addr: %llx handle: %x status: %d\n",
|
|
ret,
|
|
pending_idx,
|
|
tx_unmap_op.host_addr,
|
|
tx_unmap_op.handle,
|
|
tx_unmap_op.status);
|
|
BUG();
|
|
}
|
|
}
|
|
|
|
static inline int rx_work_todo(struct xenvif_queue *queue)
|
|
{
|
|
return (!skb_queue_empty(&queue->rx_queue) &&
|
|
xenvif_rx_ring_slots_available(queue, queue->rx_last_skb_slots));
|
|
}
|
|
|
|
static inline int tx_work_todo(struct xenvif_queue *queue)
|
|
{
|
|
if (likely(RING_HAS_UNCONSUMED_REQUESTS(&queue->tx)))
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline bool tx_dealloc_work_todo(struct xenvif_queue *queue)
|
|
{
|
|
return queue->dealloc_cons != queue->dealloc_prod;
|
|
}
|
|
|
|
void xenvif_unmap_frontend_rings(struct xenvif_queue *queue)
|
|
{
|
|
if (queue->tx.sring)
|
|
xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(queue->vif),
|
|
queue->tx.sring);
|
|
if (queue->rx.sring)
|
|
xenbus_unmap_ring_vfree(xenvif_to_xenbus_device(queue->vif),
|
|
queue->rx.sring);
|
|
}
|
|
|
|
int xenvif_map_frontend_rings(struct xenvif_queue *queue,
|
|
grant_ref_t tx_ring_ref,
|
|
grant_ref_t rx_ring_ref)
|
|
{
|
|
void *addr;
|
|
struct xen_netif_tx_sring *txs;
|
|
struct xen_netif_rx_sring *rxs;
|
|
|
|
int err = -ENOMEM;
|
|
|
|
err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(queue->vif),
|
|
tx_ring_ref, &addr);
|
|
if (err)
|
|
goto err;
|
|
|
|
txs = (struct xen_netif_tx_sring *)addr;
|
|
BACK_RING_INIT(&queue->tx, txs, PAGE_SIZE);
|
|
|
|
err = xenbus_map_ring_valloc(xenvif_to_xenbus_device(queue->vif),
|
|
rx_ring_ref, &addr);
|
|
if (err)
|
|
goto err;
|
|
|
|
rxs = (struct xen_netif_rx_sring *)addr;
|
|
BACK_RING_INIT(&queue->rx, rxs, PAGE_SIZE);
|
|
|
|
return 0;
|
|
|
|
err:
|
|
xenvif_unmap_frontend_rings(queue);
|
|
return err;
|
|
}
|
|
|
|
static void xenvif_start_queue(struct xenvif_queue *queue)
|
|
{
|
|
if (xenvif_schedulable(queue->vif))
|
|
xenvif_wake_queue(queue);
|
|
}
|
|
|
|
/* Only called from the queue's thread, it handles the situation when the guest
|
|
* doesn't post enough requests on the receiving ring.
|
|
* First xenvif_start_xmit disables QDisc and start a timer, and then either the
|
|
* timer fires, or the guest send an interrupt after posting new request. If it
|
|
* is the timer, the carrier is turned off here.
|
|
* */
|
|
static void xenvif_rx_purge_event(struct xenvif_queue *queue)
|
|
{
|
|
/* Either the last unsuccesful skb or at least 1 slot should fit */
|
|
int needed = queue->rx_last_skb_slots ?
|
|
queue->rx_last_skb_slots : 1;
|
|
|
|
/* It is assumed that if the guest post new slots after this, the RX
|
|
* interrupt will set the QUEUE_STATUS_RX_PURGE_EVENT bit and wake up
|
|
* the thread again
|
|
*/
|
|
set_bit(QUEUE_STATUS_RX_STALLED, &queue->status);
|
|
if (!xenvif_rx_ring_slots_available(queue, needed)) {
|
|
rtnl_lock();
|
|
if (netif_carrier_ok(queue->vif->dev)) {
|
|
/* Timer fired and there are still no slots. Turn off
|
|
* everything except the interrupts
|
|
*/
|
|
netif_carrier_off(queue->vif->dev);
|
|
skb_queue_purge(&queue->rx_queue);
|
|
queue->rx_last_skb_slots = 0;
|
|
if (net_ratelimit())
|
|
netdev_err(queue->vif->dev, "Carrier off due to lack of guest response on queue %d\n", queue->id);
|
|
} else {
|
|
/* Probably an another queue already turned the carrier
|
|
* off, make sure nothing is stucked in the internal
|
|
* queue of this queue
|
|
*/
|
|
skb_queue_purge(&queue->rx_queue);
|
|
queue->rx_last_skb_slots = 0;
|
|
}
|
|
rtnl_unlock();
|
|
} else if (!netif_carrier_ok(queue->vif->dev)) {
|
|
unsigned int num_queues = queue->vif->num_queues;
|
|
unsigned int i;
|
|
/* The carrier was down, but an interrupt kicked
|
|
* the thread again after new requests were
|
|
* posted
|
|
*/
|
|
clear_bit(QUEUE_STATUS_RX_STALLED,
|
|
&queue->status);
|
|
rtnl_lock();
|
|
netif_carrier_on(queue->vif->dev);
|
|
netif_tx_wake_all_queues(queue->vif->dev);
|
|
rtnl_unlock();
|
|
|
|
for (i = 0; i < num_queues; i++) {
|
|
struct xenvif_queue *temp = &queue->vif->queues[i];
|
|
|
|
xenvif_napi_schedule_or_enable_events(temp);
|
|
}
|
|
if (net_ratelimit())
|
|
netdev_err(queue->vif->dev, "Carrier on again\n");
|
|
} else {
|
|
/* Queuing were stopped, but the guest posted
|
|
* new requests and sent an interrupt
|
|
*/
|
|
clear_bit(QUEUE_STATUS_RX_STALLED,
|
|
&queue->status);
|
|
del_timer_sync(&queue->rx_stalled);
|
|
xenvif_start_queue(queue);
|
|
}
|
|
}
|
|
|
|
int xenvif_kthread_guest_rx(void *data)
|
|
{
|
|
struct xenvif_queue *queue = data;
|
|
struct sk_buff *skb;
|
|
|
|
while (!kthread_should_stop()) {
|
|
wait_event_interruptible(queue->wq,
|
|
rx_work_todo(queue) ||
|
|
queue->vif->disabled ||
|
|
test_bit(QUEUE_STATUS_RX_PURGE_EVENT, &queue->status) ||
|
|
kthread_should_stop());
|
|
|
|
if (kthread_should_stop())
|
|
break;
|
|
|
|
/* This frontend is found to be rogue, disable it in
|
|
* kthread context. Currently this is only set when
|
|
* netback finds out frontend sends malformed packet,
|
|
* but we cannot disable the interface in softirq
|
|
* context so we defer it here, if this thread is
|
|
* associated with queue 0.
|
|
*/
|
|
if (unlikely(queue->vif->disabled && queue->id == 0)) {
|
|
xenvif_carrier_off(queue->vif);
|
|
} else if (unlikely(queue->vif->disabled)) {
|
|
/* kthread_stop() would be called upon this thread soon,
|
|
* be a bit proactive
|
|
*/
|
|
skb_queue_purge(&queue->rx_queue);
|
|
queue->rx_last_skb_slots = 0;
|
|
} else if (unlikely(test_and_clear_bit(QUEUE_STATUS_RX_PURGE_EVENT,
|
|
&queue->status))) {
|
|
xenvif_rx_purge_event(queue);
|
|
} else if (!netif_carrier_ok(queue->vif->dev)) {
|
|
/* Another queue stalled and turned the carrier off, so
|
|
* purge the internal queue of queues which were not
|
|
* blocked
|
|
*/
|
|
skb_queue_purge(&queue->rx_queue);
|
|
queue->rx_last_skb_slots = 0;
|
|
}
|
|
|
|
if (!skb_queue_empty(&queue->rx_queue))
|
|
xenvif_rx_action(queue);
|
|
|
|
cond_resched();
|
|
}
|
|
|
|
/* Bin any remaining skbs */
|
|
while ((skb = skb_dequeue(&queue->rx_queue)) != NULL)
|
|
dev_kfree_skb(skb);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static bool xenvif_dealloc_kthread_should_stop(struct xenvif_queue *queue)
|
|
{
|
|
/* Dealloc thread must remain running until all inflight
|
|
* packets complete.
|
|
*/
|
|
return kthread_should_stop() &&
|
|
!atomic_read(&queue->inflight_packets);
|
|
}
|
|
|
|
int xenvif_dealloc_kthread(void *data)
|
|
{
|
|
struct xenvif_queue *queue = data;
|
|
|
|
for (;;) {
|
|
wait_event_interruptible(queue->dealloc_wq,
|
|
tx_dealloc_work_todo(queue) ||
|
|
xenvif_dealloc_kthread_should_stop(queue));
|
|
if (xenvif_dealloc_kthread_should_stop(queue))
|
|
break;
|
|
|
|
xenvif_tx_dealloc_action(queue);
|
|
cond_resched();
|
|
}
|
|
|
|
/* Unmap anything remaining*/
|
|
if (tx_dealloc_work_todo(queue))
|
|
xenvif_tx_dealloc_action(queue);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __init netback_init(void)
|
|
{
|
|
int rc = 0;
|
|
|
|
if (!xen_domain())
|
|
return -ENODEV;
|
|
|
|
/* Allow as many queues as there are CPUs, by default */
|
|
xenvif_max_queues = num_online_cpus();
|
|
|
|
if (fatal_skb_slots < XEN_NETBK_LEGACY_SLOTS_MAX) {
|
|
pr_info("fatal_skb_slots too small (%d), bump it to XEN_NETBK_LEGACY_SLOTS_MAX (%d)\n",
|
|
fatal_skb_slots, XEN_NETBK_LEGACY_SLOTS_MAX);
|
|
fatal_skb_slots = XEN_NETBK_LEGACY_SLOTS_MAX;
|
|
}
|
|
|
|
rc = xenvif_xenbus_init();
|
|
if (rc)
|
|
goto failed_init;
|
|
|
|
rx_drain_timeout_jiffies = msecs_to_jiffies(rx_drain_timeout_msecs);
|
|
|
|
#ifdef CONFIG_DEBUG_FS
|
|
xen_netback_dbg_root = debugfs_create_dir("xen-netback", NULL);
|
|
if (IS_ERR_OR_NULL(xen_netback_dbg_root))
|
|
pr_warn("Init of debugfs returned %ld!\n",
|
|
PTR_ERR(xen_netback_dbg_root));
|
|
#endif /* CONFIG_DEBUG_FS */
|
|
|
|
return 0;
|
|
|
|
failed_init:
|
|
return rc;
|
|
}
|
|
|
|
module_init(netback_init);
|
|
|
|
static void __exit netback_fini(void)
|
|
{
|
|
#ifdef CONFIG_DEBUG_FS
|
|
if (!IS_ERR_OR_NULL(xen_netback_dbg_root))
|
|
debugfs_remove_recursive(xen_netback_dbg_root);
|
|
#endif /* CONFIG_DEBUG_FS */
|
|
xenvif_xenbus_fini();
|
|
}
|
|
module_exit(netback_fini);
|
|
|
|
MODULE_LICENSE("Dual BSD/GPL");
|
|
MODULE_ALIAS("xen-backend:vif");
|