target: Make se_tmr_lock IRQ-safe

transport_lookup_tmr_lun() can be called from interrupt context and
therefore needs to use IRQ-safe spinlock functions.  Fix this up, and
to make the locking work, convert the other uses of se_tmr_lock to be
IRQ-disabling.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

diff --git a/drivers/target/target_core_device.c b/drivers/target/target_core_device.c
index 6d93d96..f13e294 100644 (file)
--- a/drivers/target/target_core_device.c
+++ b/drivers/target/target_core_device.c
@@ -181,6 +181,7 @@ int transport_lookup_tmr_lun(struct se_cmd *se_cmd, u32 unpacked_lun)
        struct se_lun *se_lun = NULL;
        struct se_session *se_sess = se_cmd->se_sess;
        struct se_tmr_req *se_tmr = se_cmd->se_tmr_req;
+       unsigned long flags;
 
        if (unpacked_lun >= TRANSPORT_MAX_LUNS_PER_TPG) {
                se_cmd->scsi_sense_reason = TCM_NON_EXISTENT_LUN;
@@ -188,7 +189,7 @@ int transport_lookup_tmr_lun(struct se_cmd *se_cmd, u32 unpacked_lun)
                return -ENODEV;
        }
 
-       spin_lock_irq(&se_sess->se_node_acl->device_list_lock);
+       spin_lock_irqsave(&se_sess->se_node_acl->device_list_lock, flags);
        se_cmd->se_deve = &se_sess->se_node_acl->device_list[unpacked_lun];
        deve = se_cmd->se_deve;
 
@@ -200,7 +201,7 @@ int transport_lookup_tmr_lun(struct se_cmd *se_cmd, u32 unpacked_lun)
                se_cmd->orig_fe_lun = unpacked_lun;
                se_cmd->se_orig_obj_ptr = se_cmd->se_dev;
        }
-       spin_unlock_irq(&se_sess->se_node_acl->device_list_lock);
+       spin_unlock_irqrestore(&se_sess->se_node_acl->device_list_lock, flags);
 
        if (!se_lun) {
                printk(KERN_INFO "TARGET_CORE[%s]: Detected NON_EXISTENT_LUN"
@@ -223,9 +224,9 @@ int transport_lookup_tmr_lun(struct se_cmd *se_cmd, u32 unpacked_lun)
        se_cmd->se_dev = se_lun->lun_se_dev;
        se_tmr->tmr_dev = se_lun->lun_se_dev;
 
-       spin_lock(&se_tmr->tmr_dev->se_tmr_lock);
+       spin_lock_irqsave(&se_tmr->tmr_dev->se_tmr_lock, flags);
        list_add_tail(&se_tmr->tmr_list, &se_tmr->tmr_dev->dev_tmr_list);
-       spin_unlock(&se_tmr->tmr_dev->se_tmr_lock);
+       spin_unlock_irqrestore(&se_tmr->tmr_dev->se_tmr_lock, flags);
 
        return 0;
 }

diff --git a/drivers/target/target_core_tmr.c b/drivers/target/target_core_tmr.c
index 5c20de3..f1feea3 100644 (file)
--- a/drivers/target/target_core_tmr.c
+++ b/drivers/target/target_core_tmr.c
@@ -80,9 +80,9 @@ void core_tmr_release_req(
                return;
        }
 
-       spin_lock(&dev->se_tmr_lock);
+       spin_lock_irq(&dev->se_tmr_lock);
        list_del(&tmr->tmr_list);
-       spin_unlock(&dev->se_tmr_lock);
+       spin_unlock_irq(&dev->se_tmr_lock);
 
        kmem_cache_free(se_tmr_req_cache, tmr);
 }
@@ -154,7 +154,7 @@ int core_tmr_lun_reset(
         * Release all pending and outgoing TMRs aside from the received
         * LUN_RESET tmr..
         */
-       spin_lock(&dev->se_tmr_lock);
+       spin_lock_irq(&dev->se_tmr_lock);
        list_for_each_entry_safe(tmr_p, tmr_pp, &dev->dev_tmr_list, tmr_list) {
                /*
                 * Allow the received TMR to return with FUNCTION_COMPLETE.
@@ -176,17 +176,17 @@ int core_tmr_lun_reset(
                    (core_scsi3_check_cdb_abort_and_preempt(
                                        preempt_and_abort_list, cmd) != 0))
                        continue;
-               spin_unlock(&dev->se_tmr_lock);
+               spin_unlock_irq(&dev->se_tmr_lock);
 
                spin_lock_irqsave(&cmd->t_state_lock, flags);
                if (!(atomic_read(&cmd->t_transport_active))) {
                        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-                       spin_lock(&dev->se_tmr_lock);
+                       spin_lock_irq(&dev->se_tmr_lock);
                        continue;
                }
                if (cmd->t_state == TRANSPORT_ISTATE_PROCESSING) {
                        spin_unlock_irqrestore(&cmd->t_state_lock, flags);
-                       spin_lock(&dev->se_tmr_lock);
+                       spin_lock_irq(&dev->se_tmr_lock);
                        continue;
                }
                DEBUG_LR("LUN_RESET: %s releasing TMR %p Function: 0x%02x,"
@@ -196,9 +196,9 @@ int core_tmr_lun_reset(
                spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 
                transport_cmd_finish_abort_tmr(cmd);
-               spin_lock(&dev->se_tmr_lock);
+               spin_lock_irq(&dev->se_tmr_lock);
        }
-       spin_unlock(&dev->se_tmr_lock);
+       spin_unlock_irq(&dev->se_tmr_lock);
        /*
         * Complete outstanding struct se_task CDBs with TASK_ABORTED SAM status.
         * This is following sam4r17, section 5.6 Aborting commands, Table 38