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author | Mike Christie <michaelc@cs.wisc.edu> | 2008-05-21 15:54:18 -0500 |
---|---|---|
committer | James Bottomley <James.Bottomley@HansenPartnership.com> | 2008-07-12 08:22:22 -0500 |
commit | 913e5bf435617aa529919a4f7567f849f9f35f9f (patch) | |
tree | db7357d78d7d6f20358d61bf88a8137ad044a5a5 /drivers/scsi/libiscsi.c | |
parent | 3cf7b233ffc45d4fc381221f74d24f10e692c4ea (diff) | |
download | kernel_samsung_smdk4412-913e5bf435617aa529919a4f7567f849f9f35f9f.zip kernel_samsung_smdk4412-913e5bf435617aa529919a4f7567f849f9f35f9f.tar.gz kernel_samsung_smdk4412-913e5bf435617aa529919a4f7567f849f9f35f9f.tar.bz2 |
[SCSI] libiscsi, iser, tcp: remove recv_lock
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>
Diffstat (limited to 'drivers/scsi/libiscsi.c')
-rw-r--r-- | drivers/scsi/libiscsi.c | 152 |
1 files changed, 86 insertions, 66 deletions
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c index c723e60..9c267b4 100644 --- a/drivers/scsi/libiscsi.c +++ b/drivers/scsi/libiscsi.c @@ -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 { @@ -697,6 +702,31 @@ static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr, } /** + * 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 * @hdr: iscsi header @@ -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; @@ -2257,17 +2293,6 @@ static void iscsi_start_session_recovery(struct iscsi_session *session, } /* - * 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 * the recovery state again @@ -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 |