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[SCSI] libiscsi, iser, tcp: remove recv_lock

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The recv lock was defined so the iscsi layer could block
the recv path from processing IO during recovery. It
turns out iser just set a lock to that pointer which was pointless.

We now disconnect the transport connection before doing recovery
so we do not need the recv lock. For iscsi_tcp we still stop
the recv path incase older tools are being used.

This patch also has iscsi_itt_to_ctask user grab the session lock
and has the caller access the task with the lock or get a ref
to it in case the target is broken and sends a tmf success response
then sends data or a response for the command that was supposed to
be affected bty the tmf.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This commit is contained in:
Mike Christie 2008-05-21 15:54:18 -05:00 committed by James Bottomley
parent 3cf7b233ff
commit 913e5bf435
6 changed files with 144 additions and 117 deletions
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20
drivers/infiniband/ulp/iser/iscsi_iser.c
View File

@ -281,9 +281,6 @@ iscsi_iser_conn_create(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
conn->max_recv_dlength = 128;
iser_conn = conn->dd_data;
/* currently this is the only field which need to be initiated */
rwlock_init(&iser_conn->lock);
conn->dd_data = iser_conn;
iser_conn->iscsi_conn = conn;
@ -342,9 +339,6 @@ iscsi_iser_conn_bind(struct iscsi_cls_session *cls_session,
ib_conn->iser_conn = iser_conn;
iser_conn->ib_conn = ib_conn;
iser_conn_get(ib_conn);
conn->recv_lock = &iser_conn->lock;
return 0;
}
@ -355,12 +349,18 @@ iscsi_iser_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
struct iscsi_iser_conn *iser_conn = conn->dd_data;
struct iser_conn *ib_conn = iser_conn->ib_conn;
iscsi_conn_stop(cls_conn, flag);
/*
* There is no unbind event so the stop callback
* must release the ref from the bind.
* Userspace may have goofed up and not bound the connection or
* might have only partially setup the connection.
*/
iser_conn_put(ib_conn);
if (ib_conn) {
iscsi_conn_stop(cls_conn, flag);
/*
* There is no unbind event so the stop callback
* must release the ref from the bind.
*/
iser_conn_put(ib_conn);
}
iser_conn->ib_conn = NULL;
}

2
drivers/infiniband/ulp/iser/iscsi_iser.h
View File

@ -263,8 +263,6 @@ struct iser_conn {
struct iscsi_iser_conn {
struct iscsi_conn *iscsi_conn;/* ptr to iscsi conn */
struct iser_conn *ib_conn; /* iSER IB conn */
rwlock_t lock;
};
struct iscsi_iser_task {

6
drivers/infiniband/ulp/iser/iser_initiator.c
View File

@ -558,7 +558,12 @@ void iser_rcv_completion(struct iser_desc *rx_desc,
opcode = hdr->opcode & ISCSI_OPCODE_MASK;
if (opcode == ISCSI_OP_SCSI_CMD_RSP) {
spin_lock(&conn->iscsi_conn->session->lock);
task = iscsi_itt_to_ctask(conn->iscsi_conn, hdr->itt);
if (task)
__iscsi_get_task(task);
spin_unlock(&conn->iscsi_conn->session->lock);
if (!task)
iser_err("itt can't be matched to task!!! "
"conn %p opcode %d itt %d\n",
@ -568,6 +573,7 @@ void iser_rcv_completion(struct iser_desc *rx_desc,
iser_dbg("itt %d task %p\n",hdr->itt, task);
iser_task->status = ISER_TASK_STATUS_COMPLETED;
iser_task_rdma_finalize(iser_task);
iscsi_put_task(task);
}
}
iser_dto_buffs_release(dto);

73
drivers/scsi/iscsi_tcp.c
View File

@ -741,7 +741,6 @@ static int
iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
{
int rc = 0, opcode, ahslen;
struct iscsi_session *session = conn->session;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_task *task;
@ -770,17 +769,17 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
switch(opcode) {
case ISCSI_OP_SCSI_DATA_IN:
spin_lock(&conn->session->lock);
task = iscsi_itt_to_ctask(conn, hdr->itt);
if (!task)
return ISCSI_ERR_BAD_ITT;
if (!task->sc)
return ISCSI_ERR_NO_SCSI_CMD;
rc = ISCSI_ERR_BAD_ITT;
else
rc = iscsi_data_rsp(conn, task);
if (rc) {
spin_unlock(&conn->session->lock);
break;
}
spin_lock(&conn->session->lock);
rc = iscsi_data_rsp(conn, task);
spin_unlock(&conn->session->lock);
if (rc)
return rc;
if (tcp_conn->in.datalen) {
struct iscsi_tcp_task *tcp_task = task->dd_data;
struct hash_desc *rx_hash = NULL;
@ -801,15 +800,19 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
"datalen=%d)\n", tcp_conn,
tcp_task->data_offset,
tcp_conn->in.datalen);
return iscsi_segment_seek_sg(&tcp_conn->in.segment,
sdb->table.sgl,
sdb->table.nents,
tcp_task->data_offset,
tcp_conn->in.datalen,
iscsi_tcp_process_data_in,
rx_hash);
rc = iscsi_segment_seek_sg(&tcp_conn->in.segment,
sdb->table.sgl,
sdb->table.nents,
tcp_task->data_offset,
tcp_conn->in.datalen,
iscsi_tcp_process_data_in,
rx_hash);
spin_unlock(&conn->session->lock);
return rc;
}
/* fall through */
rc = __iscsi_complete_pdu(conn, hdr, NULL, 0);
spin_unlock(&conn->session->lock);
break;
case ISCSI_OP_SCSI_CMD_RSP:
if (tcp_conn->in.datalen) {
iscsi_tcp_data_recv_prep(tcp_conn);
@ -818,20 +821,17 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
break;
case ISCSI_OP_R2T:
spin_lock(&conn->session->lock);
task = iscsi_itt_to_ctask(conn, hdr->itt);
if (!task)
return ISCSI_ERR_BAD_ITT;
if (!task->sc)
return ISCSI_ERR_NO_SCSI_CMD;
if (ahslen)
rc = ISCSI_ERR_BAD_ITT;
else if (ahslen)
rc = ISCSI_ERR_AHSLEN;
else if (task->sc->sc_data_direction == DMA_TO_DEVICE) {
spin_lock(&session->lock);
else if (task->sc->sc_data_direction == DMA_TO_DEVICE)
rc = iscsi_r2t_rsp(conn, task);
spin_unlock(&session->lock);
} else
else
rc = ISCSI_ERR_PROTO;
spin_unlock(&conn->session->lock);
break;
case ISCSI_OP_LOGIN_RSP:
case ISCSI_OP_TEXT_RSP:
@ -1553,7 +1553,6 @@ iscsi_tcp_release_conn(struct iscsi_conn *conn)
spin_lock_bh(&session->lock);
tcp_conn->sock = NULL;
conn->recv_lock = NULL;
spin_unlock_bh(&session->lock);
sockfd_put(sock);
}
@ -1578,6 +1577,19 @@ static void
iscsi_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
/* userspace may have goofed up and not bound us */
if (!tcp_conn->sock)
return;
/*
* Make sure our recv side is stopped.
* Older tools called conn stop before ep_disconnect
* so IO could still be coming in.
*/
write_lock_bh(&tcp_conn->sock->sk->sk_callback_lock);
set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
write_unlock_bh(&tcp_conn->sock->sk->sk_callback_lock);
iscsi_conn_stop(cls_conn, flag);
iscsi_tcp_release_conn(conn);
@ -1671,13 +1683,6 @@ iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session,
sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
sk->sk_allocation = GFP_ATOMIC;
/* FIXME: disable Nagle's algorithm */
/*
* Intercept TCP callbacks for sendfile like receive
* processing.
*/
conn->recv_lock = &sk->sk_callback_lock;
iscsi_conn_set_callbacks(conn);
tcp_conn->sendpage = tcp_conn->sock->ops->sendpage;
/*

152
drivers/scsi/libiscsi.c
View File

@ -362,10 +362,11 @@ static void iscsi_complete_command(struct iscsi_task *task)
}
}
static void __iscsi_get_task(struct iscsi_task *task)
void __iscsi_get_task(struct iscsi_task *task)
{
atomic_inc(&task->refcount);
}
EXPORT_SYMBOL_GPL(__iscsi_get_task);
static void __iscsi_put_task(struct iscsi_task *task)
{
@ -403,9 +404,13 @@ static void fail_command(struct iscsi_conn *conn, struct iscsi_task *task,
conn->session->queued_cmdsn--;
else
conn->session->tt->cleanup_task(conn, task);
/*
* Check if cleanup_task dropped the lock and the command completed,
*/
if (!task->sc)
return;
sc->result = err;
if (!scsi_bidi_cmnd(sc))
scsi_set_resid(sc, scsi_bufflen(sc));
else {
@ -696,6 +701,31 @@ static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
return 0;
}
/**
* iscsi_itt_to_task - look up task by itt
* @conn: iscsi connection
* @itt: itt
*
* This should be used for mgmt tasks like login and nops, or if
* the LDD's itt space does not include the session age.
*
* The session lock must be held.
*/
static struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt)
{
struct iscsi_session *session = conn->session;
uint32_t i;
if (itt == RESERVED_ITT)
return NULL;
i = get_itt(itt);
if (i >= session->cmds_max)
return NULL;
return session->cmds[i];
}
/**
* __iscsi_complete_pdu - complete pdu
* @conn: iscsi conn
@ -707,8 +737,8 @@ static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
* queuecommand or send generic. session lock must be held and verify
* itt must have been called.
*/
static int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
char *data, int datalen)
int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
char *data, int datalen)
{
struct iscsi_session *session = conn->session;
int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0;
@ -758,22 +788,36 @@ static int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
goto out;
}
task = session->cmds[itt];
switch(opcode) {
case ISCSI_OP_SCSI_CMD_RSP:
if (!task->sc) {
rc = ISCSI_ERR_NO_SCSI_CMD;
break;
}
BUG_ON((void*)task != task->sc->SCp.ptr);
case ISCSI_OP_SCSI_DATA_IN:
task = iscsi_itt_to_ctask(conn, hdr->itt);
if (!task)
return ISCSI_ERR_BAD_ITT;
break;
case ISCSI_OP_R2T:
/*
* LLD handles R2Ts if they need to.
*/
return 0;
case ISCSI_OP_LOGOUT_RSP:
case ISCSI_OP_LOGIN_RSP:
case ISCSI_OP_TEXT_RSP:
case ISCSI_OP_SCSI_TMFUNC_RSP:
case ISCSI_OP_NOOP_IN:
task = iscsi_itt_to_task(conn, hdr->itt);
if (!task)
return ISCSI_ERR_BAD_ITT;
break;
default:
return ISCSI_ERR_BAD_OPCODE;
}
switch(opcode) {
case ISCSI_OP_SCSI_CMD_RSP:
iscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen);
break;
case ISCSI_OP_SCSI_DATA_IN:
if (!task->sc) {
rc = ISCSI_ERR_NO_SCSI_CMD;
break;
}
BUG_ON((void*)task != task->sc->SCp.ptr);
if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
conn->scsirsp_pdus_cnt++;
iscsi_update_cmdsn(session,
@ -781,9 +825,6 @@ static int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
__iscsi_put_task(task);
}
break;
case ISCSI_OP_R2T:
/* LLD handles this for now */
break;
case ISCSI_OP_LOGOUT_RSP:
iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
if (datalen) {
@ -841,6 +882,7 @@ recv_pdu:
__iscsi_put_task(task);
return rc;
}
EXPORT_SYMBOL_GPL(__iscsi_complete_pdu);
int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
char *data, int datalen)
@ -857,7 +899,6 @@ EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
{
struct iscsi_session *session = conn->session;
struct iscsi_task *task;
uint32_t i;
if (itt == RESERVED_ITT)
@ -867,8 +908,7 @@ int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
(session->age << ISCSI_AGE_SHIFT)) {
iscsi_conn_printk(KERN_ERR, conn,
"received itt %x expected session age (%x)\n",
(__force u32)itt,
session->age & ISCSI_AGE_MASK);
(__force u32)itt, session->age);
return ISCSI_ERR_BAD_ITT;
}
@ -879,42 +919,36 @@ int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
"%u.\n", i, session->cmds_max);
return ISCSI_ERR_BAD_ITT;
}
task = session->cmds[i];
if (task->sc && task->sc->SCp.phase != session->age) {
iscsi_conn_printk(KERN_ERR, conn,
"iscsi: task's session age %d, "
"expected %d\n", task->sc->SCp.phase,
session->age);
return ISCSI_ERR_SESSION_FAILED;
}
return 0;
}
EXPORT_SYMBOL_GPL(iscsi_verify_itt);
struct iscsi_task *
iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
/**
* iscsi_itt_to_ctask - look up ctask by itt
* @conn: iscsi connection
* @itt: itt
*
* This should be used for cmd tasks.
*
* The session lock must be held.
*/
struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
{
struct iscsi_session *session = conn->session;
struct iscsi_task *task;
uint32_t i;
if (iscsi_verify_itt(conn, itt))
return NULL;
if (itt == RESERVED_ITT)
task = iscsi_itt_to_task(conn, itt);
if (!task || !task->sc)
return NULL;
i = get_itt(itt);
if (i >= session->cmds_max)
return NULL;
task = session->cmds[i];
if (!task->sc)
return NULL;
if (task->sc->SCp.phase != session->age)
if (task->sc->SCp.phase != conn->session->age) {
iscsi_session_printk(KERN_ERR, conn->session,
"task's session age %d, expected %d\n",
task->sc->SCp.phase, conn->session->age);
return NULL;
}
return task;
}
@ -1620,16 +1654,20 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
switch (conn->tmf_state) {
case TMF_SUCCESS:
spin_unlock_bh(&session->lock);
/*
* stop tx side incase the target had sent a abort rsp but
* the initiator was still writing out data.
*/
iscsi_suspend_tx(conn);
/*
* clean up task if aborted. grab the recv lock as a writer
* we do not stop the recv side because targets have been
* good and have never sent us a successful tmf response
* then sent more data for the cmd.
*/
write_lock_bh(conn->recv_lock);
spin_lock(&session->lock);
fail_command(conn, task, DID_ABORT << 16);
conn->tmf_state = TMF_INITIAL;
spin_unlock(&session->lock);
write_unlock_bh(conn->recv_lock);
iscsi_start_tx(conn);
goto success_unlocked;
case TMF_TIMEDOUT:
@ -1729,13 +1767,11 @@ int iscsi_eh_device_reset(struct scsi_cmnd *sc)
spin_unlock_bh(&session->lock);
iscsi_suspend_tx(conn);
/* need to grab the recv lock then session lock */
write_lock_bh(conn->recv_lock);
spin_lock(&session->lock);
fail_all_commands(conn, sc->device->lun, DID_ERROR);
conn->tmf_state = TMF_INITIAL;
spin_unlock(&session->lock);
write_unlock_bh(conn->recv_lock);
iscsi_start_tx(conn);
goto done;
@ -2256,17 +2292,6 @@ static void iscsi_start_session_recovery(struct iscsi_session *session,
return;
}
/*
* The LLD either freed/unset the lock on us, or userspace called
* stop but did not create a proper connection (connection was never
* bound or it was unbound then stop was called).
*/
if (!conn->recv_lock) {
spin_unlock_bh(&session->lock);
mutex_unlock(&session->eh_mutex);
return;
}
/*
* When this is called for the in_login state, we only want to clean
* up the login task and connection. We do not need to block and set
@ -2283,11 +2308,6 @@ static void iscsi_start_session_recovery(struct iscsi_session *session,
spin_unlock_bh(&session->lock);
iscsi_suspend_tx(conn);
write_lock_bh(conn->recv_lock);
set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
write_unlock_bh(conn->recv_lock);
/*
* for connection level recovery we should not calculate
* header digest. conn->hdr_size used for optimization

8
include/scsi/libiscsi.h
View File

@ -138,11 +138,6 @@ struct iscsi_conn {
struct iscsi_cls_conn *cls_conn; /* ptr to class connection */
void *dd_data; /* iscsi_transport data */
struct iscsi_session *session; /* parent session */
/*
* LLDs should set this lock. It protects the transport recv
* code
*/
rwlock_t *recv_lock;
/*
* conn_stop() flag: stop to recover, stop to terminate
*/
@ -374,10 +369,13 @@ extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
char *, uint32_t);
extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
char *, int);
extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
char *, int);
extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
extern void iscsi_requeue_task(struct iscsi_task *task);
extern void iscsi_put_task(struct iscsi_task *task);
extern void __iscsi_get_task(struct iscsi_task *task);
/*
* generic helpers