[SCSI] qla1280: error recovery rewrite

The driver now waits for the scsi commands associated with a
particular error recovery step to be returned to the mid-layer,
and returns the appropriate SUCCESS or FAILED status.  Removes
unneeded polling of chip for interrupts.

This patch also bumps the driver version number.

Signed-off-by: Michael Reed <mdr@sgi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

2 files changed, 159 insertions, 134 deletions

diff --git a/drivers/scsi/qla1280.c b/drivers/scsi/qla1280.c
index 0cbad4982db9..8371d917a9a2 100644
--- a/drivers/scsi/qla1280.c
+++ b/drivers/scsi/qla1280.c
@@ -17,9 +17,12 @@
 * General Public License for more details.
 *
 ******************************************************************************/
-#define QLA1280_VERSION      "3.26"
+#define QLA1280_VERSION      "3.27"
 /*****************************************************************************
     Revision History:
+    Rev  3.27, February 10, 2009, Michael Reed
+        - General code cleanup.
+        - Improve error recovery.
     Rev  3.26, January 16, 2006 Jes Sorensen
         - Ditch all < 2.6 support
     Rev  3.25.1, February 10, 2005 Christoph Hellwig
@@ -718,6 +721,8 @@ qla1280_queuecommand(struct scsi_cmnd *cmd, void (*fn)(struct scsi_cmnd *))
         cmd->scsi_done = fn;
         sp->cmd = cmd;
         sp->flags = 0;
+        sp->wait = NULL;
+        CMD_HANDLE(cmd) = (unsigned char *)NULL;
 
         qla1280_print_scsi_cmd(5, cmd);
 
@@ -742,14 +747,6 @@ enum action {
         ADAPTER_RESET,
 };
 
-/* timer action for error action processor */
-static void qla1280_error_wait_timeout(unsigned long __data)
-{
-        struct scsi_cmnd *cmd = (struct scsi_cmnd *)__data;
-        struct srb *sp = (struct srb *)CMD_SP(cmd);
-
-        complete(sp->wait);
-}
 
 static void qla1280_mailbox_timeout(unsigned long __data)
 {
@@ -764,6 +761,65 @@ static void qla1280_mailbox_timeout(unsigned long __data)
         complete(ha->mailbox_wait);
 }
 
+static int
+_qla1280_wait_for_single_command(struct scsi_qla_host *ha, struct srb *sp,
+                                 struct completion *wait)
+{
+        int     status = FAILED;
+        struct scsi_cmnd *cmd = sp->cmd;
+
+        spin_unlock_irq(ha->host->host_lock);
+        wait_for_completion_timeout(wait, 4*HZ);
+        spin_lock_irq(ha->host->host_lock);
+        sp->wait = NULL;
+        if(CMD_HANDLE(cmd) == COMPLETED_HANDLE) {
+                status = SUCCESS;
+                (*cmd->scsi_done)(cmd);
+        }
+        return status;
+}
+
+static int
+qla1280_wait_for_single_command(struct scsi_qla_host *ha, struct srb *sp)
+{
+        DECLARE_COMPLETION_ONSTACK(wait);
+
+        sp->wait = &wait;
+        return _qla1280_wait_for_single_command(ha, sp, &wait);
+}
+
+static int
+qla1280_wait_for_pending_commands(struct scsi_qla_host *ha, int bus, int target)
+{
+        int             cnt;
+        int             status;
+        struct srb      *sp;
+        struct scsi_cmnd *cmd;
+
+        status = SUCCESS;
+
+        /*
+         * Wait for all commands with the designated bus/target
+         * to be completed by the firmware
+         */
+        for (cnt = 0; cnt < MAX_OUTSTANDING_COMMANDS; cnt++) {
+                sp = ha->outstanding_cmds[cnt];
+                if (sp) {
+                        cmd = sp->cmd;
+
+                        if (bus >= 0 && SCSI_BUS_32(cmd) != bus)
+                                continue;
+                        if (target >= 0 && SCSI_TCN_32(cmd) != target)
+                                continue;
+
+                        status = qla1280_wait_for_single_command(ha, sp);
+                        if (status == FAILED)
+                                break;
+                }
+        }
+        return status;
+}
+
 /**************************************************************************
  * qla1280_error_action
  *    The function will attempt to perform a specified error action and
@@ -777,11 +833,6 @@ static void qla1280_mailbox_timeout(unsigned long __data)
  * Returns:
  *      SUCCESS or FAILED
  *
- * Note:
- *      Resetting the bus always succeeds - is has to, otherwise the
- *      kernel will panic! Try a surgical technique - sending a BUS
- *      DEVICE RESET message - on the offending target before pulling
- *      the SCSI bus reset line.
  **************************************************************************/
 static int
 qla1280_error_action(struct scsi_cmnd *cmd, enum action action)
@@ -789,15 +840,19 @@ qla1280_error_action(struct scsi_cmnd *cmd, enum action action)
         struct scsi_qla_host *ha;
         int bus, target, lun;
         struct srb *sp;
-        uint16_t data;
-        unsigned char *handle;
-        int result, i;
+        int i, found;
+        int result=FAILED;
+        int wait_for_bus=-1;
+        int wait_for_target = -1;
         DECLARE_COMPLETION_ONSTACK(wait);
-        struct timer_list timer;
 
         ENTER("qla1280_error_action");
 
         ha = (struct scsi_qla_host *)(CMD_HOST(cmd)->hostdata);
+        sp = (struct srb *)CMD_SP(cmd);
+        bus = SCSI_BUS_32(cmd);
+        target = SCSI_TCN_32(cmd);
+        lun = SCSI_LUN_32(cmd);
 
         dprintk(4, "error_action %i, istatus 0x%04x\n", action,
                 RD_REG_WORD(&ha->iobase->istatus));
@@ -811,73 +866,42 @@ qla1280_error_action(struct scsi_cmnd *cmd, enum action action)
                        "Handle=0x%p, action=0x%x\n",
                        ha->host_no, cmd, CMD_HANDLE(cmd), action);
 
-        sp = (struct srb *)CMD_SP(cmd);
-        handle = CMD_HANDLE(cmd);
-
-        /* Check for pending interrupts. */
-        data = qla1280_debounce_register(&ha->iobase->istatus);
-        /*
-         * The io_request_lock is held when the reset handler is called, hence
-         * the interrupt handler cannot be running in parallel as it also
-         * grabs the lock. /Jes
-         */
-        if (data & RISC_INT)
-                qla1280_isr(ha, &ha->done_q);
-
         /*
-         * Determine the suggested action that the mid-level driver wants
-         * us to perform.
+         * Check to see if we have the command in the outstanding_cmds[]
+         * array.  If not then it must have completed before this error
+         * action was initiated.  If the error_action isn't ABORT_COMMAND
+         * then the driver must proceed with the requested action.
          */
-        if (handle == (unsigned char *)INVALID_HANDLE || handle == NULL) {
-                if(action == ABORT_COMMAND) {
-                        /* we never got this command */
-                        printk(KERN_INFO "qla1280: Aborting a NULL handle\n");
-                        return SUCCESS; /* no action - we don't have command */
+        found = -1;
+        for (i = 0; i < MAX_OUTSTANDING_COMMANDS; i++) {
+                if (sp == ha->outstanding_cmds[i]) {
+                        found = i;
+                        sp->wait = &wait; /* we'll wait for it to complete */
+                        break;
                 }
-        } else {
-                sp->wait = &wait;
         }
 
-        bus = SCSI_BUS_32(cmd);
-        target = SCSI_TCN_32(cmd);
-        lun = SCSI_LUN_32(cmd);
+        if (found < 0) {        /* driver doesn't have command */
+                result = SUCCESS;
+                if (qla1280_verbose) {
+                        printk(KERN_INFO
+                               "scsi(%ld:%d:%d:%d): specified command has "
+                               "already completed.\n", ha->host_no, bus,
+                                target, lun);
+                }
+        }
 
-        /* Overloading result.  Here it means the success or fail of the
-         * *issue* of the action.  When we return from the routine, it must
-         * mean the actual success or fail of the action */
-        result = FAILED;
         switch (action) {
-        case ABORT_COMMAND:
-                if ((sp->flags & SRB_ABORT_PENDING)) {
-                        printk(KERN_WARNING
-                               "scsi(): Command has a pending abort "
-                               "message - ABORT_PENDING.\n");
-                        /* This should technically be impossible since we
-                         * now wait for abort completion */
-                        break;
-                }
 
-                for (i = 0; i < MAX_OUTSTANDING_COMMANDS; i++) {
-                        if (sp == ha->outstanding_cmds[i]) {
-                                dprintk(1, "qla1280: RISC aborting command\n");
-                                if (qla1280_abort_command(ha, sp, i) == 0)
-                                        result = SUCCESS;
-                                else {
-                                        /*
-                                         * Since we don't know what might
-                                         * have happend to the command, it
-                                         * is unsafe to remove it from the
-                                         * device's queue at this point.
-                                         * Wait and let the escalation
-                                         * process take care of it.
-                                         */
-                                        printk(KERN_WARNING
-                                               "scsi(%li:%i:%i:%i): Unable"
-                                               " to abort command!\n",
-                                               ha->host_no, bus, target, lun);
-                                }
-                        }
-                }
+        case ABORT_COMMAND:
+                dprintk(1, "qla1280: RISC aborting command\n");
+                /*
+                 * The abort might fail due to race when the host_lock
+                 * is released to issue the abort.  As such, we
+                 * don't bother to check the return status.
+                 */
+                if (found >= 0)
+                        qla1280_abort_command(ha, sp, found);
                 break;
 
         case DEVICE_RESET:
@@ -885,16 +909,21 @@ qla1280_error_action(struct scsi_cmnd *cmd, enum action action)
                         printk(KERN_INFO
                                "scsi(%ld:%d:%d:%d): Queueing device reset "
                                "command.\n", ha->host_no, bus, target, lun);
-                if (qla1280_device_reset(ha, bus, target) == 0)
-                        result = SUCCESS;
+                if (qla1280_device_reset(ha, bus, target) == 0) {
+                        /* issued device reset, set wait conditions */
+                        wait_for_bus = bus;
+                        wait_for_target = target;
+                }
                 break;
 
         case BUS_RESET:
                 if (qla1280_verbose)
                         printk(KERN_INFO "qla1280(%ld:%d): Issued bus "
                                "reset.\n", ha->host_no, bus);
-                if (qla1280_bus_reset(ha, bus) == 0)
-                        result = SUCCESS;
+                if (qla1280_bus_reset(ha, bus) == 0) {
+                        /* issued bus reset, set wait conditions */
+                        wait_for_bus = bus;
+                }
                 break;
 
         case ADAPTER_RESET:
@@ -907,55 +936,48 @@ qla1280_error_action(struct scsi_cmnd *cmd, enum action action)
                                "continue automatically\n", ha->host_no);
                 }
                 ha->flags.reset_active = 1;
-                /*
-                 * We restarted all of the commands automatically, so the
-                 * mid-level code can expect completions momentitarily.
-                 */
-                if (qla1280_abort_isp(ha) == 0)
-                        result = SUCCESS;
+
+                if (qla1280_abort_isp(ha) != 0) {       /* it's dead */
+                        result = FAILED;
+                }
 
                 ha->flags.reset_active = 0;
         }
 
-        if (!list_empty(&ha->done_q))
-                qla1280_done(ha);
-
-        /* If we didn't manage to issue the action, or we have no
-         * command to wait for, exit here */
-        if (result == FAILED || handle == NULL ||
-            handle == (unsigned char *)INVALID_HANDLE) {
-                /*
-                 * Clear completion queue to avoid qla1280_done() trying
-                 * to complete the command at a later stage after we
-                 * have exited the current context
-                 */
-                sp->wait = NULL;
-                goto leave;
-        }
+        /*
+         * At this point, the host_lock has been released and retaken
+         * by the issuance of the mailbox command.
+         * Wait for the command passed in by the mid-layer if it
+         * was found by the driver.  It might have been returned
+         * between eh recovery steps, hence the check of the "found"
+         * variable.
+         */
 
-        /* set up a timer just in case we're really jammed */
-        init_timer(&timer);
-        timer.expires = jiffies + 4*HZ;
-        timer.data = (unsigned long)cmd;
-        timer.function = qla1280_error_wait_timeout;
-        add_timer(&timer);
+        if (found >= 0)
+                result = _qla1280_wait_for_single_command(ha, sp, &wait);
 
-        /* wait for the action to complete (or the timer to expire) */
-        spin_unlock_irq(ha->host->host_lock);
-        wait_for_completion(&wait);
-        del_timer_sync(&timer);
-        spin_lock_irq(ha->host->host_lock);
-        sp->wait = NULL;
+        if (action == ABORT_COMMAND && result != SUCCESS) {
+                printk(KERN_WARNING
+                       "scsi(%li:%i:%i:%i): "
+                       "Unable to abort command!\n",
+                       ha->host_no, bus, target, lun);
+        }
 
-        /* the only action we might get a fail for is abort */
-        if (action == ABORT_COMMAND) {
-                if(sp->flags & SRB_ABORTED)
-                        result = SUCCESS;
-                else
-                        result = FAILED;
+        /*
+         * If the command passed in by the mid-layer has been
+         * returned by the board, then wait for any additional
+         * commands which are supposed to complete based upon
+         * the error action.
+         *
+         * All commands are unconditionally returned during a
+         * call to qla1280_abort_isp(), ADAPTER_RESET.  No need
+         * to wait for them.
+         */
+        if (result == SUCCESS && wait_for_bus >= 0) {
+                result = qla1280_wait_for_pending_commands(ha,
+                                        wait_for_bus, wait_for_target);
         }
 
- leave:
         dprintk(1, "RESET returning %d\n", result);
 
         LEAVE("qla1280_error_action");
@@ -1258,7 +1280,8 @@ qla1280_done(struct scsi_qla_host *ha)
                 switch ((CMD_RESULT(cmd) >> 16)) {
                 case DID_RESET:
                         /* Issue marker command. */
-                        qla1280_marker(ha, bus, target, 0, MK_SYNC_ID);
+                        if (!ha->flags.abort_isp_active)
+                                qla1280_marker(ha, bus, target, 0, MK_SYNC_ID);
                         break;
                 case DID_ABORT:
                         sp->flags &= ~SRB_ABORT_PENDING;
@@ -1272,12 +1295,11 @@ qla1280_done(struct scsi_qla_host *ha)
                 scsi_dma_unmap(cmd);
 
                 /* Call the mid-level driver interrupt handler */
-                CMD_HANDLE(sp->cmd) = (unsigned char *)INVALID_HANDLE;
                 ha->actthreads--;
 
-                (*(cmd)->scsi_done)(cmd);
-
-                if(sp->wait != NULL)
+                if (sp->wait == NULL)
+                        (*(cmd)->scsi_done)(cmd);
+                else
                         complete(sp->wait);
         }
         LEAVE("qla1280_done");
@@ -3415,6 +3437,7 @@ qla1280_isr(struct scsi_qla_host *ha, struct list_head *done_q)
 
                                         /* Save ISP completion status */
                                         CMD_RESULT(sp->cmd) = 0;
+                                        CMD_HANDLE(sp->cmd) = COMPLETED_HANDLE;
 
                                         /* Place block on done queue */
                                         list_add_tail(&sp->list, done_q);
@@ -3681,6 +3704,8 @@ qla1280_status_entry(struct scsi_qla_host *ha, struct response *pkt,
                 }
         }
 
+        CMD_HANDLE(sp->cmd) = COMPLETED_HANDLE;
+
         /* Place command on done queue. */
         list_add_tail(&sp->list, done_q);
  out:
@@ -3736,6 +3761,8 @@ qla1280_error_entry(struct scsi_qla_host *ha, struct response *pkt,
                         CMD_RESULT(sp->cmd) = DID_ERROR << 16;
                 }
 
+                CMD_HANDLE(sp->cmd) = COMPLETED_HANDLE;
+
                 /* Place command on done queue. */
                 list_add_tail(&sp->list, done_q);
         }
@@ -3786,19 +3813,16 @@ qla1280_abort_isp(struct scsi_qla_host *ha)
                 struct scsi_cmnd *cmd;
                 sp = ha->outstanding_cmds[cnt];
                 if (sp) {
-
                         cmd = sp->cmd;
                         CMD_RESULT(cmd) = DID_RESET << 16;
-
-                        sp->cmd = NULL;
+                        CMD_HANDLE(cmd) = COMPLETED_HANDLE;
                         ha->outstanding_cmds[cnt] = NULL;
-
-                        (*cmd->scsi_done)(cmd);
-
-                        sp->flags = 0;
+                        list_add_tail(&sp->list, &ha->done_q);
                 }
         }
 
+        qla1280_done(ha);
+
         status = qla1280_load_firmware(ha);
         if (status)
                 goto out;
diff --git a/drivers/scsi/qla1280.h b/drivers/scsi/qla1280.h
index d7c44b8d2b4f..834884b9eed5 100644
--- a/drivers/scsi/qla1280.h
+++ b/drivers/scsi/qla1280.h
@@ -88,7 +88,8 @@
 
 /* Maximum outstanding commands in ISP queues */
 #define MAX_OUTSTANDING_COMMANDS        512
-#define INVALID_HANDLE                  (MAX_OUTSTANDING_COMMANDS + 2)
+#define COMPLETED_HANDLE                ((unsigned char *) \
+                                        (MAX_OUTSTANDING_COMMANDS + 2))
 
 /* ISP request and response entry counts (37-65535) */
 #define REQUEST_ENTRY_CNT               255 /* Number of request entries. */