[SCSI] iscsi tcp: fix iscsi xmit state machine

If iscsi_tcp partially sends a header, it would recalculate the
header size and readd the size of the digest (if header digests
are used).This would cause us to send sizeof(digest) extra bytes
when we sent the rest of the header.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This commit is contained in:
Mike Christie 2007-05-30 12:57:17 -05:00 committed by James Bottomley
parent b2c6416736
commit 218432c680
3 changed files with 151 additions and 117 deletions

View File

@ -109,7 +109,7 @@ iscsi_hdr_digest(struct iscsi_conn *conn, struct iscsi_buf *buf,
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
crypto_hash_digest(&tcp_conn->tx_hash, &buf->sg, buf->sg.length, crc);
buf->sg.length = tcp_conn->hdr_size;
buf->sg.length += sizeof(u32);
}
static inline int
@ -423,7 +423,7 @@ iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
tcp_ctask->exp_datasn = r2tsn + 1;
__kfifo_put(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*));
tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
tcp_ctask->xmstate |= XMSTATE_SOL_HDR_INIT;
list_move_tail(&ctask->running, &conn->xmitqueue);
scsi_queue_work(session->host, &conn->xmitwork);
@ -1284,41 +1284,10 @@ static void iscsi_set_padding(struct iscsi_tcp_cmd_task *tcp_ctask,
static void
iscsi_tcp_cmd_init(struct iscsi_cmd_task *ctask)
{
struct scsi_cmnd *sc = ctask->sc;
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
BUG_ON(__kfifo_len(tcp_ctask->r2tqueue));
tcp_ctask->sent = 0;
tcp_ctask->sg_count = 0;
tcp_ctask->exp_datasn = 0;
if (sc->sc_data_direction == DMA_TO_DEVICE) {
tcp_ctask->xmstate = XMSTATE_W_HDR;
BUG_ON(sc->request_bufflen == 0);
if (sc->use_sg) {
struct scatterlist *sg = sc->request_buffer;
iscsi_buf_init_sg(&tcp_ctask->sendbuf, sg);
tcp_ctask->sg = sg + 1;
tcp_ctask->bad_sg = sg + sc->use_sg;
} else {
iscsi_buf_init_iov(&tcp_ctask->sendbuf,
sc->request_buffer,
sc->request_bufflen);
tcp_ctask->sg = NULL;
tcp_ctask->bad_sg = NULL;
}
debug_scsi("cmd [itt 0x%x total %d imm_data %d "
"unsol count %d, unsol offset %d]\n",
ctask->itt, sc->request_bufflen, ctask->imm_count,
ctask->unsol_count, ctask->unsol_offset);
} else
tcp_ctask->xmstate = XMSTATE_R_HDR;
iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)ctask->hdr,
sizeof(struct iscsi_hdr));
tcp_ctask->xmstate = XMSTATE_CMD_HDR_INIT;
}
/**
@ -1331,9 +1300,11 @@ iscsi_tcp_cmd_init(struct iscsi_cmd_task *ctask)
* call it again later, or recover. '0' return code means successful
* xmit.
*
* Management xmit state machine consists of two states:
* IN_PROGRESS_IMM_HEAD - PDU Header xmit in progress
* IN_PROGRESS_IMM_DATA - PDU Data xmit in progress
* Management xmit state machine consists of these states:
* XMSTATE_IMM_HDR_INIT - calculate digest of PDU Header
* XMSTATE_IMM_HDR - PDU Header xmit in progress
* XMSTATE_IMM_DATA - PDU Data xmit in progress
* XMSTATE_IDLE - management PDU is done
**/
static int
iscsi_tcp_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
@ -1344,23 +1315,34 @@ iscsi_tcp_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
debug_scsi("mtask deq [cid %d state %x itt 0x%x]\n",
conn->id, tcp_mtask->xmstate, mtask->itt);
if (tcp_mtask->xmstate & XMSTATE_IMM_HDR) {
tcp_mtask->xmstate &= ~XMSTATE_IMM_HDR;
if (mtask->data_count)
if (tcp_mtask->xmstate & XMSTATE_IMM_HDR_INIT) {
iscsi_buf_init_iov(&tcp_mtask->headbuf, (char*)mtask->hdr,
sizeof(struct iscsi_hdr));
if (mtask->data_count) {
tcp_mtask->xmstate |= XMSTATE_IMM_DATA;
iscsi_buf_init_iov(&tcp_mtask->sendbuf,
(char*)mtask->data,
mtask->data_count);
}
if (conn->c_stage != ISCSI_CONN_INITIAL_STAGE &&
conn->stop_stage != STOP_CONN_RECOVER &&
conn->hdrdgst_en)
iscsi_hdr_digest(conn, &tcp_mtask->headbuf,
(u8*)tcp_mtask->hdrext);
tcp_mtask->sent = 0;
tcp_mtask->xmstate &= ~XMSTATE_IMM_HDR_INIT;
tcp_mtask->xmstate |= XMSTATE_IMM_HDR;
}
if (tcp_mtask->xmstate & XMSTATE_IMM_HDR) {
rc = iscsi_sendhdr(conn, &tcp_mtask->headbuf,
mtask->data_count);
if (rc) {
tcp_mtask->xmstate |= XMSTATE_IMM_HDR;
if (mtask->data_count)
tcp_mtask->xmstate &= ~XMSTATE_IMM_DATA;
if (rc)
return rc;
}
tcp_mtask->xmstate &= ~XMSTATE_IMM_HDR;
}
if (tcp_mtask->xmstate & XMSTATE_IMM_DATA) {
@ -1394,55 +1376,75 @@ iscsi_tcp_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
return 0;
}
static inline int
iscsi_send_read_hdr(struct iscsi_conn *conn,
struct iscsi_tcp_cmd_task *tcp_ctask)
{
int rc;
tcp_ctask->xmstate &= ~XMSTATE_R_HDR;
if (conn->hdrdgst_en)
iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
(u8*)tcp_ctask->hdrext);
rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, 0);
if (!rc) {
BUG_ON(tcp_ctask->xmstate != XMSTATE_IDLE);
return 0; /* wait for Data-In */
}
tcp_ctask->xmstate |= XMSTATE_R_HDR;
return rc;
}
static inline int
iscsi_send_write_hdr(struct iscsi_conn *conn,
struct iscsi_cmd_task *ctask)
static int
iscsi_send_cmd_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct scsi_cmnd *sc = ctask->sc;
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
int rc;
int rc = 0;
tcp_ctask->xmstate &= ~XMSTATE_W_HDR;
if (conn->hdrdgst_en)
iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
(u8*)tcp_ctask->hdrext);
rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->imm_count);
if (rc) {
tcp_ctask->xmstate |= XMSTATE_W_HDR;
return rc;
}
if (tcp_ctask->xmstate & XMSTATE_CMD_HDR_INIT) {
tcp_ctask->sent = 0;
tcp_ctask->sg_count = 0;
tcp_ctask->exp_datasn = 0;
if (ctask->imm_count) {
tcp_ctask->xmstate |= XMSTATE_IMM_DATA;
iscsi_set_padding(tcp_ctask, ctask->imm_count);
if (sc->sc_data_direction == DMA_TO_DEVICE) {
if (sc->use_sg) {
struct scatterlist *sg = sc->request_buffer;
if (ctask->conn->datadgst_en) {
iscsi_data_digest_init(ctask->conn->dd_data, tcp_ctask);
tcp_ctask->immdigest = 0;
iscsi_buf_init_sg(&tcp_ctask->sendbuf, sg);
tcp_ctask->sg = sg + 1;
tcp_ctask->bad_sg = sg + sc->use_sg;
} else {
iscsi_buf_init_iov(&tcp_ctask->sendbuf,
sc->request_buffer,
sc->request_bufflen);
tcp_ctask->sg = NULL;
tcp_ctask->bad_sg = NULL;
}
debug_scsi("cmd [itt 0x%x total %d imm_data %d "
"unsol count %d, unsol offset %d]\n",
ctask->itt, sc->request_bufflen,
ctask->imm_count, ctask->unsol_count,
ctask->unsol_offset);
}
iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)ctask->hdr,
sizeof(struct iscsi_hdr));
if (conn->hdrdgst_en)
iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
(u8*)tcp_ctask->hdrext);
tcp_ctask->xmstate &= ~XMSTATE_CMD_HDR_INIT;
tcp_ctask->xmstate |= XMSTATE_CMD_HDR_XMIT;
}
if (ctask->unsol_count)
tcp_ctask->xmstate |= XMSTATE_UNS_HDR | XMSTATE_UNS_INIT;
return 0;
if (tcp_ctask->xmstate & XMSTATE_CMD_HDR_XMIT) {
rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->imm_count);
if (rc)
return rc;
tcp_ctask->xmstate &= ~XMSTATE_CMD_HDR_XMIT;
if (sc->sc_data_direction != DMA_TO_DEVICE)
return 0;
if (ctask->imm_count) {
tcp_ctask->xmstate |= XMSTATE_IMM_DATA;
iscsi_set_padding(tcp_ctask, ctask->imm_count);
if (ctask->conn->datadgst_en) {
iscsi_data_digest_init(ctask->conn->dd_data,
tcp_ctask);
tcp_ctask->immdigest = 0;
}
}
if (ctask->unsol_count)
tcp_ctask->xmstate |=
XMSTATE_UNS_HDR | XMSTATE_UNS_INIT;
}
return rc;
}
static int
@ -1631,9 +1633,7 @@ static int iscsi_send_sol_pdu(struct iscsi_conn *conn,
struct iscsi_data_task *dtask;
int left, rc;
if (tcp_ctask->xmstate & XMSTATE_SOL_HDR) {
tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
if (tcp_ctask->xmstate & XMSTATE_SOL_HDR_INIT) {
if (!tcp_ctask->r2t) {
spin_lock_bh(&session->lock);
__kfifo_get(tcp_ctask->r2tqueue, (void*)&tcp_ctask->r2t,
@ -1647,12 +1647,19 @@ static int iscsi_send_sol_pdu(struct iscsi_conn *conn,
if (conn->hdrdgst_en)
iscsi_hdr_digest(conn, &r2t->headbuf,
(u8*)dtask->hdrext);
tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR_INIT;
tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
}
if (tcp_ctask->xmstate & XMSTATE_SOL_HDR) {
r2t = tcp_ctask->r2t;
dtask = &r2t->dtask;
rc = iscsi_sendhdr(conn, &r2t->headbuf, r2t->data_count);
if (rc) {
tcp_ctask->xmstate &= ~XMSTATE_SOL_DATA;
tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
if (rc)
return rc;
}
tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
if (conn->datadgst_en) {
iscsi_data_digest_init(conn->dd_data, tcp_ctask);
@ -1684,8 +1691,6 @@ static int iscsi_send_sol_pdu(struct iscsi_conn *conn,
left = r2t->data_length - r2t->sent;
if (left) {
iscsi_solicit_data_cont(conn, ctask, r2t, left);
tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
goto send_hdr;
}
@ -1700,8 +1705,6 @@ static int iscsi_send_sol_pdu(struct iscsi_conn *conn,
if (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t,
sizeof(void*))) {
tcp_ctask->r2t = r2t;
tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
spin_unlock_bh(&session->lock);
goto send_hdr;
}
@ -1710,6 +1713,46 @@ static int iscsi_send_sol_pdu(struct iscsi_conn *conn,
return 0;
}
/**
* iscsi_tcp_ctask_xmit - xmit normal PDU task
* @conn: iscsi connection
* @ctask: iscsi command task
*
* Notes:
* The function can return -EAGAIN in which case caller must
* call it again later, or recover. '0' return code means successful
* xmit.
* The function is devided to logical helpers (above) for the different
* xmit stages.
*
*iscsi_send_cmd_hdr()
* XMSTATE_CMD_HDR_INIT - prepare Header and Data buffers Calculate
* Header Digest
* XMSTATE_CMD_HDR_XMIT - Transmit header in progress
*
*iscsi_send_padding
* XMSTATE_W_PAD - Prepare and send pading
* XMSTATE_W_RESEND_PAD - retry send pading
*
*iscsi_send_digest
* XMSTATE_W_RESEND_DATA_DIGEST - Finalize and send Data Digest
* XMSTATE_W_RESEND_DATA_DIGEST - retry sending digest
*
*iscsi_send_unsol_hdr
* XMSTATE_UNS_INIT - prepare un-solicit data header and digest
* XMSTATE_UNS_HDR - send un-solicit header
*
*iscsi_send_unsol_pdu
* XMSTATE_UNS_DATA - send un-solicit data in progress
*
*iscsi_send_sol_pdu
* XMSTATE_SOL_HDR_INIT - solicit data header and digest initialize
* XMSTATE_SOL_HDR - send solicit header
* XMSTATE_SOL_DATA - send solicit data
*
*iscsi_tcp_ctask_xmit
* XMSTATE_IMM_DATA - xmit managment data (??)
**/
static int
iscsi_tcp_ctask_xmit(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
@ -1725,14 +1768,11 @@ iscsi_tcp_ctask_xmit(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
if (ctask->mtask)
return rc;
if (tcp_ctask->xmstate & XMSTATE_R_HDR)
return iscsi_send_read_hdr(conn, tcp_ctask);
if (tcp_ctask->xmstate & XMSTATE_W_HDR) {
rc = iscsi_send_write_hdr(conn, ctask);
if (rc)
return rc;
}
rc = iscsi_send_cmd_hdr(conn, ctask);
if (rc)
return rc;
if (ctask->sc->sc_data_direction != DMA_TO_DEVICE)
return 0;
if (tcp_ctask->xmstate & XMSTATE_IMM_DATA) {
rc = iscsi_send_data(ctask, &tcp_ctask->sendbuf, &tcp_ctask->sg,
@ -1913,15 +1953,7 @@ iscsi_tcp_mgmt_init(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask,
char *data, uint32_t data_size)
{
struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
iscsi_buf_init_iov(&tcp_mtask->headbuf, (char*)mtask->hdr,
sizeof(struct iscsi_hdr));
tcp_mtask->xmstate = XMSTATE_IMM_HDR;
tcp_mtask->sent = 0;
if (mtask->data_count)
iscsi_buf_init_iov(&tcp_mtask->sendbuf, (char*)mtask->data,
mtask->data_count);
tcp_mtask->xmstate = XMSTATE_IMM_HDR_INIT;
}
static int

View File

@ -32,8 +32,8 @@
/* xmit state machine */
#define XMSTATE_IDLE 0x0
#define XMSTATE_R_HDR 0x1
#define XMSTATE_W_HDR 0x2
#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
@ -44,6 +44,8 @@
#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_PAD_LEN 4
#define ISCSI_SG_TABLESIZE SG_ALL

View File

@ -125,6 +125,7 @@ static void iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
MAX_COMMAND_SIZE - sc->cmd_len);
ctask->data_count = 0;
ctask->imm_count = 0;
if (sc->sc_data_direction == DMA_TO_DEVICE) {
hdr->flags |= ISCSI_FLAG_CMD_WRITE;
/*
@ -141,7 +142,6 @@ static void iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask)
*
* pad_count bytes to be sent as zero-padding
*/
ctask->imm_count = 0;
ctask->unsol_count = 0;
ctask->unsol_offset = 0;
ctask->unsol_datasn = 0;