diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-08-04 19:47:37 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-08-04 19:47:37 -0700 |
commit | 746fc76b820dce8cbb17a1e5e70a1558db4d7406 (patch) | |
tree | 724898336ce5b4fd8c79d817c06b978929e28410 /drivers/scsi/libiscsi.c | |
parent | 328141e51e6fc79d21168bfd4e356dddc2ec7491 (diff) | |
parent | 8fcdc238ce1b492e1f57a73a2ce4131d63f45397 (diff) |
Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"Updates to the usual drivers (ufs, qla2xx, target, lpfc, smartpqi,
mpi3mr).
The main driver change that might cause issues on down the road is the
conversion of some of our oldest surviving drivers to the DMA API
(should only affect m68k).
The only major core change is the rework of async resume; the rest are
either completely trivial or for updating deprecated APIs"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (195 commits)
scsi: target: Remove XDWRITEREAD emulated support
scsi: megaraid: Remove the static variable initialisation
scsi: ch: Do not initialise statics to 0
scsi: ufs: core: Fix spelling mistake "Cannnot" -> "Cannot"
scsi: target: iscsi: Do not require target authentication
scsi: target: iscsi: Allow AuthMethod=None
scsi: target: iscsi: Support base64 in CHAP
scsi: target: iscsi: Add support for extended CDB AHS
scsi: ufs: dt-bindings: Add SC8280XP binding
scsi: target: iscsi: Fix clang -Wformat warnings
scsi: ufs: core: Read device property for ref clock
scsi: libsas: Resume SAS host for phy reset or enable via sysfs
scsi: hisi_sas: Modify v3 HW SATA completion error processing
scsi: hisi_sas: Relocate DMA unmap of SMP task
scsi: hisi_sas: Remove unnecessary variable to hold DMA map elements
scsi: hisi_sas: Call hisi_sas_slave_configure() from slave_configure_v3_hw()
scsi: mpi3mr: Delete a stray tab
scsi: mpi3mr: Unlock on error path
scsi: mpi3mr: Reduce VD queue depth on detecting throttling
scsi: mpi3mr: Resource Based Metering
...
Diffstat (limited to 'drivers/scsi/libiscsi.c')
-rw-r--r-- | drivers/scsi/libiscsi.c | 313 |
1 files changed, 212 insertions, 101 deletions
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c index 797abf4f5399..d95f4bcdeb2e 100644 --- a/drivers/scsi/libiscsi.c +++ b/drivers/scsi/libiscsi.c @@ -83,7 +83,9 @@ MODULE_PARM_DESC(debug_libiscsi_eh, "%s " dbg_fmt, __func__, ##arg); \ } while (0); -inline void iscsi_conn_queue_work(struct iscsi_conn *conn) +#define ISCSI_CMD_COMPL_WAIT 5 + +inline void iscsi_conn_queue_xmit(struct iscsi_conn *conn) { struct Scsi_Host *shost = conn->session->host; struct iscsi_host *ihost = shost_priv(shost); @@ -91,7 +93,17 @@ inline void iscsi_conn_queue_work(struct iscsi_conn *conn) if (ihost->workq) queue_work(ihost->workq, &conn->xmitwork); } -EXPORT_SYMBOL_GPL(iscsi_conn_queue_work); +EXPORT_SYMBOL_GPL(iscsi_conn_queue_xmit); + +inline void iscsi_conn_queue_recv(struct iscsi_conn *conn) +{ + struct Scsi_Host *shost = conn->session->host; + struct iscsi_host *ihost = shost_priv(shost); + + if (ihost->workq && !test_bit(ISCSI_CONN_FLAG_SUSPEND_RX, &conn->flags)) + queue_work(ihost->workq, &conn->recvwork); +} +EXPORT_SYMBOL_GPL(iscsi_conn_queue_recv); static void __iscsi_update_cmdsn(struct iscsi_session *session, uint32_t exp_cmdsn, uint32_t max_cmdsn) @@ -472,12 +484,18 @@ static void iscsi_free_task(struct iscsi_task *task) } } -void __iscsi_get_task(struct iscsi_task *task) +bool iscsi_get_task(struct iscsi_task *task) { - refcount_inc(&task->refcount); + return refcount_inc_not_zero(&task->refcount); } -EXPORT_SYMBOL_GPL(__iscsi_get_task); +EXPORT_SYMBOL_GPL(iscsi_get_task); +/** + * __iscsi_put_task - drop the refcount on a task + * @task: iscsi_task to drop the refcount on + * + * The back_lock must be held when calling in case it frees the task. + */ void __iscsi_put_task(struct iscsi_task *task) { if (refcount_dec_and_test(&task->refcount)) @@ -489,10 +507,11 @@ void iscsi_put_task(struct iscsi_task *task) { struct iscsi_session *session = task->conn->session; - /* regular RX path uses back_lock */ - spin_lock_bh(&session->back_lock); - __iscsi_put_task(task); - spin_unlock_bh(&session->back_lock); + if (refcount_dec_and_test(&task->refcount)) { + spin_lock_bh(&session->back_lock); + iscsi_free_task(task); + spin_unlock_bh(&session->back_lock); + } } EXPORT_SYMBOL_GPL(iscsi_put_task); @@ -557,16 +576,19 @@ static bool cleanup_queued_task(struct iscsi_task *task) struct iscsi_conn *conn = task->conn; bool early_complete = false; - /* Bad target might have completed task while it was still running */ + /* + * We might have raced where we handled a R2T early and got a response + * but have not yet taken the task off the requeue list, then a TMF or + * recovery happened and so we can still see it here. + */ if (task->state == ISCSI_TASK_COMPLETED) early_complete = true; if (!list_empty(&task->running)) { list_del_init(&task->running); /* - * If it's on a list but still running, this could be from - * a bad target sending a rsp early, cleanup from a TMF, or - * session recovery. + * If it's on a list but still running this could be cleanup + * from a TMF or session recovery. */ if (task->state == ISCSI_TASK_RUNNING || task->state == ISCSI_TASK_COMPLETED) @@ -587,20 +609,17 @@ static bool cleanup_queued_task(struct iscsi_task *task) } /* - * session frwd lock must be held and if not called for a task that is still - * pending or from the xmit thread, then xmit thread must be suspended + * session back and frwd lock must be held and if not called for a task that + * is still pending or from the xmit thread, then xmit thread must be suspended */ -static void fail_scsi_task(struct iscsi_task *task, int err) +static void __fail_scsi_task(struct iscsi_task *task, int err) { struct iscsi_conn *conn = task->conn; struct scsi_cmnd *sc; int state; - spin_lock_bh(&conn->session->back_lock); - if (cleanup_queued_task(task)) { - spin_unlock_bh(&conn->session->back_lock); + if (cleanup_queued_task(task)) return; - } if (task->state == ISCSI_TASK_PENDING) { /* @@ -619,7 +638,15 @@ static void fail_scsi_task(struct iscsi_task *task, int err) sc->result = err << 16; scsi_set_resid(sc, scsi_bufflen(sc)); iscsi_complete_task(task, state); - spin_unlock_bh(&conn->session->back_lock); +} + +static void fail_scsi_task(struct iscsi_task *task, int err) +{ + struct iscsi_session *session = task->conn->session; + + spin_lock_bh(&session->back_lock); + __fail_scsi_task(task, err); + spin_unlock_bh(&session->back_lock); } static int iscsi_prep_mgmt_task(struct iscsi_conn *conn, @@ -668,12 +695,18 @@ static int iscsi_prep_mgmt_task(struct iscsi_conn *conn, return 0; } +/** + * iscsi_alloc_mgmt_task - allocate and setup a mgmt task. + * @conn: iscsi conn that the task will be sent on. + * @hdr: iscsi pdu that will be sent. + * @data: buffer for data segment if needed. + * @data_size: length of data in bytes. + */ static struct iscsi_task * -__iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr, +iscsi_alloc_mgmt_task(struct iscsi_conn *conn, struct iscsi_hdr *hdr, char *data, uint32_t data_size) { struct iscsi_session *session = conn->session; - struct iscsi_host *ihost = shost_priv(session->host); uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK; struct iscsi_task *task; itt_t itt; @@ -754,28 +787,57 @@ __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr, task->conn->session->age); } - if (unlikely(READ_ONCE(conn->ping_task) == INVALID_SCSI_TASK)) - WRITE_ONCE(conn->ping_task, task); + return task; + +free_task: + iscsi_put_task(task); + return NULL; +} + +/** + * iscsi_send_mgmt_task - Send task created with iscsi_alloc_mgmt_task. + * @task: iscsi task to send. + * + * On failure this returns a non-zero error code, and the driver must free + * the task with iscsi_put_task; + */ +static int iscsi_send_mgmt_task(struct iscsi_task *task) +{ + struct iscsi_conn *conn = task->conn; + struct iscsi_session *session = conn->session; + struct iscsi_host *ihost = shost_priv(conn->session->host); + int rc = 0; if (!ihost->workq) { - if (iscsi_prep_mgmt_task(conn, task)) - goto free_task; + rc = iscsi_prep_mgmt_task(conn, task); + if (rc) + return rc; - if (session->tt->xmit_task(task)) - goto free_task; + rc = session->tt->xmit_task(task); + if (rc) + return rc; } else { list_add_tail(&task->running, &conn->mgmtqueue); - iscsi_conn_queue_work(conn); + iscsi_conn_queue_xmit(conn); } - return task; + return 0; +} -free_task: - /* regular RX path uses back_lock */ - spin_lock(&session->back_lock); - __iscsi_put_task(task); - spin_unlock(&session->back_lock); - return NULL; +static int __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr, + char *data, uint32_t data_size) +{ + struct iscsi_task *task; + int rc; + + task = iscsi_alloc_mgmt_task(conn, hdr, data, data_size); + if (!task) + return -ENOMEM; + + rc = iscsi_send_mgmt_task(task); + if (rc) + iscsi_put_task(task); + return rc; } int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr, @@ -786,7 +848,7 @@ int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr, int err = 0; spin_lock_bh(&session->frwd_lock); - if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size)) + if (__iscsi_conn_send_pdu(conn, hdr, data, data_size)) err = -EPERM; spin_unlock_bh(&session->frwd_lock); return err; @@ -959,7 +1021,6 @@ static int iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr) if (!rhdr) { if (READ_ONCE(conn->ping_task)) return -EINVAL; - WRITE_ONCE(conn->ping_task, INVALID_SCSI_TASK); } memset(&hdr, 0, sizeof(struct iscsi_nopout)); @@ -973,10 +1034,18 @@ static int iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr) } else hdr.ttt = RESERVED_ITT; - task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0); - if (!task) { + task = iscsi_alloc_mgmt_task(conn, (struct iscsi_hdr *)&hdr, NULL, 0); + if (!task) + return -ENOMEM; + + if (!rhdr) + WRITE_ONCE(conn->ping_task, task); + + if (iscsi_send_mgmt_task(task)) { if (!rhdr) WRITE_ONCE(conn->ping_task, NULL); + iscsi_put_task(task); + iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n"); return -EIO; } else if (!rhdr) { @@ -1434,11 +1503,17 @@ static int iscsi_xmit_task(struct iscsi_conn *conn, struct iscsi_task *task, { int rc; - spin_lock_bh(&conn->session->back_lock); - if (!conn->task) { - /* Take a ref so we can access it after xmit_task() */ - __iscsi_get_task(task); + /* + * Take a ref so we can access it after xmit_task(). + * + * This should never fail because the failure paths will have + * stopped the xmit thread. + */ + if (!iscsi_get_task(task)) { + WARN_ON_ONCE(1); + return 0; + } } else { /* Already have a ref from when we failed to send it last call */ conn->task = NULL; @@ -1449,7 +1524,7 @@ static int iscsi_xmit_task(struct iscsi_conn *conn, struct iscsi_task *task, * case a bad target sends a cmd rsp before we have handled the task. */ if (was_requeue) - __iscsi_put_task(task); + iscsi_put_task(task); /* * Do this after dropping the extra ref because if this was a requeue @@ -1461,10 +1536,8 @@ static int iscsi_xmit_task(struct iscsi_conn *conn, struct iscsi_task *task, * task and get woken up again. */ conn->task = task; - spin_unlock_bh(&conn->session->back_lock); return -ENODATA; } - spin_unlock_bh(&conn->session->back_lock); spin_unlock_bh(&conn->session->frwd_lock); rc = conn->session->tt->xmit_task(task); @@ -1472,20 +1545,16 @@ static int iscsi_xmit_task(struct iscsi_conn *conn, struct iscsi_task *task, if (!rc) { /* done with this task */ task->last_xfer = jiffies; - } - /* regular RX path uses back_lock */ - spin_lock(&conn->session->back_lock); - if (rc && task->state == ISCSI_TASK_RUNNING) { + } else { /* * get an extra ref that is released next time we access it * as conn->task above. */ - __iscsi_get_task(task); + iscsi_get_task(task); conn->task = task; } - __iscsi_put_task(task); - spin_unlock(&conn->session->back_lock); + iscsi_put_task(task); return rc; } @@ -1513,7 +1582,7 @@ void iscsi_requeue_task(struct iscsi_task *task) */ iscsi_put_task(task); } - iscsi_conn_queue_work(conn); + iscsi_conn_queue_xmit(conn); spin_unlock_bh(&conn->session->frwd_lock); } EXPORT_SYMBOL_GPL(iscsi_requeue_task); @@ -1567,6 +1636,28 @@ check_mgmt: goto done; } +check_requeue: + while (!list_empty(&conn->requeue)) { + /* + * we always do fastlogout - conn stop code will clean up. + */ + if (conn->session->state == ISCSI_STATE_LOGGING_OUT) + break; + + task = list_entry(conn->requeue.next, struct iscsi_task, + running); + + if (iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_DATA_OUT)) + break; + + list_del_init(&task->running); + rc = iscsi_xmit_task(conn, task, true); + if (rc) + goto done; + if (!list_empty(&conn->mgmtqueue)) + goto check_mgmt; + } + /* process pending command queue */ while (!list_empty(&conn->cmdqueue)) { task = list_entry(conn->cmdqueue.next, struct iscsi_task, @@ -1594,28 +1685,10 @@ check_mgmt: */ if (!list_empty(&conn->mgmtqueue)) goto check_mgmt; + if (!list_empty(&conn->requeue)) + goto check_requeue; } - while (!list_empty(&conn->requeue)) { - /* - * we always do fastlogout - conn stop code will clean up. - */ - if (conn->session->state == ISCSI_STATE_LOGGING_OUT) - break; - - task = list_entry(conn->requeue.next, struct iscsi_task, - running); - - if (iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_DATA_OUT)) - break; - - list_del_init(&task->running); - rc = iscsi_xmit_task(conn, task, true); - if (rc) - goto done; - if (!list_empty(&conn->mgmtqueue)) - goto check_mgmt; - } spin_unlock_bh(&conn->session->frwd_lock); return -ENODATA; @@ -1782,7 +1855,7 @@ int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc) } } else { list_add_tail(&task->running, &conn->cmdqueue); - iscsi_conn_queue_work(conn); + iscsi_conn_queue_xmit(conn); } session->queued_cmdsn++; @@ -1843,11 +1916,8 @@ static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn, __must_hold(&session->frwd_lock) { struct iscsi_session *session = conn->session; - struct iscsi_task *task; - task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr, - NULL, 0); - if (!task) { + if (__iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr, NULL, 0)) { spin_unlock_bh(&session->frwd_lock); iscsi_conn_printk(KERN_ERR, conn, "Could not send TMF.\n"); iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED); @@ -1895,6 +1965,7 @@ static void fail_scsi_tasks(struct iscsi_conn *conn, u64 lun, int error) struct iscsi_task *task; int i; +restart_cmd_loop: spin_lock_bh(&session->back_lock); for (i = 0; i < session->cmds_max; i++) { task = session->cmds[i]; @@ -1903,22 +1974,25 @@ static void fail_scsi_tasks(struct iscsi_conn *conn, u64 lun, int error) if (lun != -1 && lun != task->sc->device->lun) continue; - - __iscsi_get_task(task); - spin_unlock_bh(&session->back_lock); + /* + * The cmd is completing but if this is called from an eh + * callout path then when we return scsi-ml owns the cmd. Wait + * for the completion path to finish freeing the cmd. + */ + if (!iscsi_get_task(task)) { + spin_unlock_bh(&session->back_lock); + spin_unlock_bh(&session->frwd_lock); + udelay(ISCSI_CMD_COMPL_WAIT); + spin_lock_bh(&session->frwd_lock); + goto restart_cmd_loop; + } ISCSI_DBG_SESSION(session, "failing sc %p itt 0x%x state %d\n", task->sc, task->itt, task->state); - fail_scsi_task(task, error); - - spin_unlock_bh(&session->frwd_lock); - iscsi_put_task(task); - spin_lock_bh(&session->frwd_lock); - - spin_lock_bh(&session->back_lock); + __fail_scsi_task(task, error); + __iscsi_put_task(task); } - spin_unlock_bh(&session->back_lock); } @@ -1943,7 +2017,7 @@ EXPORT_SYMBOL_GPL(iscsi_suspend_queue); /** * iscsi_suspend_tx - suspend iscsi_data_xmit - * @conn: iscsi conn tp stop processing IO on. + * @conn: iscsi conn to stop processing IO on. * * This function sets the suspend bit to prevent iscsi_data_xmit * from sending new IO, and if work is queued on the xmit thread @@ -1956,15 +2030,30 @@ void iscsi_suspend_tx(struct iscsi_conn *conn) set_bit(ISCSI_CONN_FLAG_SUSPEND_TX, &conn->flags); if (ihost->workq) - flush_workqueue(ihost->workq); + flush_work(&conn->xmitwork); } EXPORT_SYMBOL_GPL(iscsi_suspend_tx); static void iscsi_start_tx(struct iscsi_conn *conn) { clear_bit(ISCSI_CONN_FLAG_SUSPEND_TX, &conn->flags); - iscsi_conn_queue_work(conn); + iscsi_conn_queue_xmit(conn); +} + +/** + * iscsi_suspend_rx - Prevent recvwork from running again. + * @conn: iscsi conn to stop. + */ +void iscsi_suspend_rx(struct iscsi_conn *conn) +{ + struct Scsi_Host *shost = conn->session->host; + struct iscsi_host *ihost = shost_priv(shost); + + set_bit(ISCSI_CONN_FLAG_SUSPEND_RX, &conn->flags); + if (ihost->workq) + flush_work(&conn->recvwork); } +EXPORT_SYMBOL_GPL(iscsi_suspend_rx); /* * We want to make sure a ping is in flight. It has timed out. @@ -2008,7 +2097,16 @@ enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc) spin_unlock(&session->back_lock); goto done; } - __iscsi_get_task(task); + if (!iscsi_get_task(task)) { + /* + * Racing with the completion path right now, so give it more + * time so that path can complete it like normal. + */ + rc = BLK_EH_RESET_TIMER; + task = NULL; + spin_unlock(&session->back_lock); + goto done; + } spin_unlock(&session->back_lock); if (session->state != ISCSI_STATE_LOGGED_IN) { @@ -2257,6 +2355,7 @@ int iscsi_eh_abort(struct scsi_cmnd *sc) ISCSI_DBG_EH(session, "aborting sc %p\n", sc); +completion_check: mutex_lock(&session->eh_mutex); spin_lock_bh(&session->frwd_lock); /* @@ -2296,13 +2395,20 @@ int iscsi_eh_abort(struct scsi_cmnd *sc) return SUCCESS; } + if (!iscsi_get_task(task)) { + spin_unlock(&session->back_lock); + spin_unlock_bh(&session->frwd_lock); + mutex_unlock(&session->eh_mutex); + /* We are just about to call iscsi_free_task so wait for it. */ + udelay(ISCSI_CMD_COMPL_WAIT); + goto completion_check; + } + + ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n", sc, task->itt); conn = session->leadconn; iscsi_get_conn(conn->cls_conn); conn->eh_abort_cnt++; age = session->age; - - ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n", sc, task->itt); - __iscsi_get_task(task); spin_unlock(&session->back_lock); if (task->state == ISCSI_TASK_PENDING) { @@ -2828,11 +2934,12 @@ static void iscsi_notify_host_removed(struct iscsi_cls_session *cls_session) /** * iscsi_host_remove - remove host and sessions * @shost: scsi host + * @is_shutdown: true if called from a driver shutdown callout * * If there are any sessions left, this will initiate the removal and wait * for the completion. */ -void iscsi_host_remove(struct Scsi_Host *shost) +void iscsi_host_remove(struct Scsi_Host *shost, bool is_shutdown) { struct iscsi_host *ihost = shost_priv(shost); unsigned long flags; @@ -2841,7 +2948,11 @@ void iscsi_host_remove(struct Scsi_Host *shost) ihost->state = ISCSI_HOST_REMOVED; spin_unlock_irqrestore(&ihost->lock, flags); - iscsi_host_for_each_session(shost, iscsi_notify_host_removed); + if (!is_shutdown) + iscsi_host_for_each_session(shost, iscsi_notify_host_removed); + else + iscsi_host_for_each_session(shost, iscsi_force_destroy_session); + wait_event_interruptible(ihost->session_removal_wq, ihost->num_sessions == 0); if (signal_pending(current)) |