android_kernel_xiaomi_sm8350/drivers/scsi/iscsi_tcp.h
Mike Christie c8dc1e523b [SCSI] iscsi bugfixes: reduce memory allocations
We currently try to allocate a max_recv_data_segment_length
which can be very large (default is 64K), and common uses
are up to 1MB. It is very very difficult to allocte this
much contiguous memory and it turns out we never even use it.
We really only need a couple of pages, so this patch has us
allocates just what we know what we need today.

Later if vendors start adding vendor specific data and
we need to handle large buffers we can do this, but for
the last 4 years we have not seen anyone do this or request
it.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-07-28 11:49:34 -05:00

176 lines
5.2 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>
/* Socket's Receive state machine */
#define IN_PROGRESS_WAIT_HEADER 0x0
#define IN_PROGRESS_HEADER_GATHER 0x1
#define IN_PROGRESS_DATA_RECV 0x2
#define IN_PROGRESS_DDIGEST_RECV 0x3
/* xmit state machine */
#define XMSTATE_IDLE 0x0
#define XMSTATE_R_HDR 0x1
#define XMSTATE_W_HDR 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_DATA_DIGEST 0x400
#define ISCSI_CONN_RCVBUF_MIN 262144
#define ISCSI_CONN_SNDBUF_MIN 262144
#define ISCSI_PAD_LEN 4
#define ISCSI_R2T_MAX 16
#define ISCSI_SG_TABLESIZE SG_ALL
#define ISCSI_TCP_MAX_CMD_LEN 16
struct socket;
/* Socket connection recieve helper */
struct iscsi_tcp_recv {
struct iscsi_hdr *hdr;
struct sk_buff *skb;
int offset;
int len;
int hdr_offset;
int copy;
int copied;
int padding;
struct iscsi_cmd_task *ctask; /* current cmd in progress */
/* copied and flipped values */
int datalen;
int datadgst;
char zero_copy_hdr;
};
struct iscsi_tcp_conn {
struct iscsi_conn *iscsi_conn;
struct socket *sock;
struct iscsi_hdr hdr; /* header placeholder */
char hdrext[4*sizeof(__u16) +
sizeof(__u32)];
int data_copied;
int stop_stage; /* conn_stop() flag: *
* stop to recover, *
* stop to terminate */
/* iSCSI connection-wide sequencing */
int hdr_size; /* PDU header size */
struct crypto_tfm *rx_tfm; /* CRC32C (Rx) */
struct crypto_tfm *data_rx_tfm; /* CRC32C (Rx) for data */
/* control data */
struct iscsi_tcp_recv in; /* TCP receive context */
int in_progress; /* connection state machine */
/* old values for socket callbacks */
void (*old_data_ready)(struct sock *, int);
void (*old_state_change)(struct sock *);
void (*old_write_space)(struct sock *);
/* xmit */
struct crypto_tfm *tx_tfm; /* CRC32C (Tx) */
struct crypto_tfm *data_tx_tfm; /* CRC32C (Tx) for data */
/* 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[sizeof(__u32)]; /* Header-Digest */
struct iscsi_buf digestbuf; /* digest buffer */
uint32_t digest; /* data digest */
};
struct iscsi_tcp_mgmt_task {
struct iscsi_hdr hdr;
char hdrext[sizeof(__u32)]; /* 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_cmd hdr;
char hdrext[4*sizeof(__u16)+ /* AHS */
sizeof(__u32)]; /* HeaderDigest */
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_r2tsn;
int r2t_data_count; /* R2T Data-Out bytes */
int data_offset;
struct iscsi_r2t_info *r2t; /* in progress R2T */
struct iscsi_queue r2tpool;
struct kfifo *r2tqueue;
struct iscsi_r2t_info **r2ts;
uint32_t datadigest; /* for recover digest */
int digest_count;
uint32_t immdigest; /* for imm data */
struct iscsi_buf immbuf; /* for imm data digest */
struct iscsi_data_task *dtask; /* data task in progress*/
struct iscsi_data_task unsol_dtask; /* unsol data task */
int digest_offset; /* for partial buff digest */
};
#endif /* ISCSI_H */