linux/drivers/scsi/iscsi_tcp.h
Olaf Kirch 6320377fd9 [SCSI] libiscsi, iscsi_tcp: iscsi pool cleanup
iscsi_pool_init simplified

iscsi_pool_init currently has a lot of duplicate kfree() calls it does
when some allocation fails. This patch simplifies the code a little by
using iscsi_pool_free to tear down the pool in case of an error.

iscsi_pool_init also returns a copy of the item array to the caller.
Not all callers use this array, so we make it optional.

Instead of allocating a second array and return that, allocate just one
array, of twice the size.

Update users of iscsi_pool_{init,free}

This patch drops the (now useless) second argument to
iscsi_pool_free, and updates all callers.

It also removes the ctask->r2ts array, which was never
used anyway. Since the items argument to iscsi_pool_init
is now optional, we can pass NULL instead.

Signed-off-by: Olaf Kirch <olaf.kirch@oracle.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-01-11 18:28:27 -06:00

187 lines
5.3 KiB
C

/*
* iSCSI Initiator TCP Transport
* Copyright (C) 2004 Dmitry Yusupov
* Copyright (C) 2004 Alex Aizman
* Copyright (C) 2005 - 2006 Mike Christie
* Copyright (C) 2006 Red Hat, Inc. All rights reserved.
* maintained by open-iscsi@googlegroups.com
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published
* by the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* See the file COPYING included with this distribution for more details.
*/
#ifndef ISCSI_TCP_H
#define ISCSI_TCP_H
#include <scsi/libiscsi.h>
/* xmit state machine */
#define XMSTATE_IDLE 0x0
#define XMSTATE_CMD_HDR_INIT 0x1
#define XMSTATE_CMD_HDR_XMIT 0x2
#define XMSTATE_IMM_HDR 0x4
#define XMSTATE_IMM_DATA 0x8
#define XMSTATE_UNS_INIT 0x10
#define XMSTATE_UNS_HDR 0x20
#define XMSTATE_UNS_DATA 0x40
#define XMSTATE_SOL_HDR 0x80
#define XMSTATE_SOL_DATA 0x100
#define XMSTATE_W_PAD 0x200
#define XMSTATE_W_RESEND_PAD 0x400
#define XMSTATE_W_RESEND_DATA_DIGEST 0x800
#define XMSTATE_IMM_HDR_INIT 0x1000
#define XMSTATE_SOL_HDR_INIT 0x2000
#define ISCSI_SG_TABLESIZE SG_ALL
#define ISCSI_TCP_MAX_CMD_LEN 16
struct crypto_hash;
struct socket;
struct iscsi_tcp_conn;
struct iscsi_chunk;
typedef int iscsi_chunk_done_fn_t(struct iscsi_tcp_conn *,
struct iscsi_chunk *);
struct iscsi_chunk {
unsigned char *data;
unsigned int size;
unsigned int copied;
unsigned int total_size;
unsigned int total_copied;
struct hash_desc *hash;
unsigned char recv_digest[ISCSI_DIGEST_SIZE];
unsigned char digest[ISCSI_DIGEST_SIZE];
unsigned int digest_len;
struct scatterlist *sg;
void *sg_mapped;
unsigned int sg_offset;
unsigned int sg_index;
unsigned int sg_count;
iscsi_chunk_done_fn_t *done;
};
/* Socket connection recieve helper */
struct iscsi_tcp_recv {
struct iscsi_hdr *hdr;
struct iscsi_chunk chunk;
/* Allocate buffer for BHS + AHS */
uint32_t hdr_buf[64];
/* copied and flipped values */
int datalen;
};
/* Socket connection send helper */
struct iscsi_tcp_send {
struct iscsi_hdr *hdr;
struct iscsi_chunk chunk;
struct iscsi_chunk data_chunk;
/* Allocate buffer for BHS + AHS */
uint32_t hdr_buf[64];
};
struct iscsi_tcp_conn {
struct iscsi_conn *iscsi_conn;
struct socket *sock;
int stop_stage; /* conn_stop() flag: *
* stop to recover, *
* stop to terminate */
/* control data */
struct iscsi_tcp_recv in; /* TCP receive context */
struct iscsi_tcp_send out; /* TCP send context */
/* old values for socket callbacks */
void (*old_data_ready)(struct sock *, int);
void (*old_state_change)(struct sock *);
void (*old_write_space)(struct sock *);
/* data and header digests */
struct hash_desc tx_hash; /* CRC32C (Tx) */
struct hash_desc rx_hash; /* CRC32C (Rx) */
/* MIB custom statistics */
uint32_t sendpage_failures_cnt;
uint32_t discontiguous_hdr_cnt;
ssize_t (*sendpage)(struct socket *, struct page *, int, size_t, int);
};
struct iscsi_buf {
struct scatterlist sg;
unsigned int sent;
char use_sendmsg;
};
struct iscsi_data_task {
struct iscsi_data hdr; /* PDU */
char hdrext[ISCSI_DIGEST_SIZE];/* Header-Digest */
struct iscsi_buf digestbuf; /* digest buffer */
uint32_t digest; /* data digest */
};
struct iscsi_tcp_mgmt_task {
struct iscsi_hdr hdr;
char hdrext[ISCSI_DIGEST_SIZE]; /* Header-Digest */
int xmstate; /* mgmt xmit progress */
struct iscsi_buf headbuf; /* header buffer */
struct iscsi_buf sendbuf; /* in progress buffer */
int sent;
};
struct iscsi_r2t_info {
__be32 ttt; /* copied from R2T */
__be32 exp_statsn; /* copied from R2T */
uint32_t data_length; /* copied from R2T */
uint32_t data_offset; /* copied from R2T */
struct iscsi_buf headbuf; /* Data-Out Header Buffer */
struct iscsi_buf sendbuf; /* Data-Out in progress buffer*/
int sent; /* R2T sequence progress */
int data_count; /* DATA-Out payload progress */
struct scatterlist *sg; /* per-R2T SG list */
int solicit_datasn;
struct iscsi_data_task dtask; /* which data task */
};
struct iscsi_tcp_cmd_task {
struct iscsi_hdr_buff {
struct iscsi_cmd cmd_hdr;
char hdrextbuf[ISCSI_MAX_AHS_SIZE +
ISCSI_DIGEST_SIZE];
} hdr;
char pad[ISCSI_PAD_LEN];
int pad_count; /* padded bytes */
struct iscsi_buf headbuf; /* header buf (xmit) */
struct iscsi_buf sendbuf; /* in progress buffer*/
int xmstate; /* xmit xtate machine */
int sent;
struct scatterlist *sg; /* per-cmd SG list */
struct scatterlist *bad_sg; /* assert statement */
int sg_count; /* SG's to process */
uint32_t exp_datasn; /* expected target's R2TSN/DataSN */
int data_offset;
struct iscsi_r2t_info *r2t; /* in progress R2T */
struct iscsi_pool r2tpool;
struct kfifo *r2tqueue;
int digest_count;
uint32_t immdigest; /* for imm data */
struct iscsi_buf immbuf; /* for imm data digest */
struct iscsi_data_task unsol_dtask; /* unsol data task */
};
#endif /* ISCSI_H */