1 files changed, 65 insertions, 155 deletions

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 3d04a9f386a..d6743b959a7 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -436,60 +436,16 @@ EXPORT_SYMBOL_GPL(scsi_execute_async);
  *
  * Arguments:   cmd     - command that is ready to be queued.
  *
- * Returns:     Nothing
- *
  * Notes:       This function has the job of initializing a number of
  *              fields related to error handling.   Typically this will
  *              be called once for each command, as required.
  */
-static int scsi_init_cmd_errh(struct scsi_cmnd *cmd)
+static void scsi_init_cmd_errh(struct scsi_cmnd *cmd)
 {
         cmd->serial_number = 0;
-
         memset(cmd->sense_buffer, 0, sizeof cmd->sense_buffer);
-
         if (cmd->cmd_len == 0)
                 cmd->cmd_len = COMMAND_SIZE(cmd->cmnd[0]);
-
-        /*
-         * We need saved copies of a number of fields - this is because
-         * error handling may need to overwrite these with different values
-         * to run different commands, and once error handling is complete,
-         * we will need to restore these values prior to running the actual
-         * command.
-         */
-        cmd->old_use_sg = cmd->use_sg;
-        cmd->old_cmd_len = cmd->cmd_len;
-        cmd->sc_old_data_direction = cmd->sc_data_direction;
-        cmd->old_underflow = cmd->underflow;
-        memcpy(cmd->data_cmnd, cmd->cmnd, sizeof(cmd->cmnd));
-        cmd->buffer = cmd->request_buffer;
-        cmd->bufflen = cmd->request_bufflen;
-
-        return 1;
-}
-
-/*
- * Function:   scsi_setup_cmd_retry()
- *
- * Purpose:    Restore the command state for a retry
- *
- * Arguments:  cmd      - command to be restored
- *
- * Returns:    Nothing
- *
- * Notes:      Immediately prior to retrying a command, we need
- *             to restore certain fields that we saved above.
- */
-void scsi_setup_cmd_retry(struct scsi_cmnd *cmd)
-{
-        memcpy(cmd->cmnd, cmd->data_cmnd, sizeof(cmd->data_cmnd));
-        cmd->request_buffer = cmd->buffer;
-        cmd->request_bufflen = cmd->bufflen;
-        cmd->use_sg = cmd->old_use_sg;
-        cmd->cmd_len = cmd->old_cmd_len;
-        cmd->sc_data_direction = cmd->sc_old_data_direction;
-        cmd->underflow = cmd->old_underflow;
 }
 
 void scsi_device_unbusy(struct scsi_device *sdev)
@@ -595,7 +551,15 @@ static void scsi_run_queue(struct request_queue *q)
                 list_del_init(&sdev->starved_entry);
                 spin_unlock_irqrestore(shost->host_lock, flags);
 
-                blk_run_queue(sdev->request_queue);
+
+                if (test_bit(QUEUE_FLAG_REENTER, &q->queue_flags) &&
+                    !test_and_set_bit(QUEUE_FLAG_REENTER,
+                                      &sdev->request_queue->queue_flags)) {
+                        blk_run_queue(sdev->request_queue);
+                        clear_bit(QUEUE_FLAG_REENTER,
+                                  &sdev->request_queue->queue_flags);
+                } else
+                        blk_run_queue(sdev->request_queue);
 
                 spin_lock_irqsave(shost->host_lock, flags);
                 if (unlikely(!list_empty(&sdev->starved_entry)))
@@ -807,22 +771,13 @@ static void scsi_free_sgtable(struct scatterlist *sgl, int index)
  */
 static void scsi_release_buffers(struct scsi_cmnd *cmd)
 {
-        struct request *req = cmd->request;
-
-        /*
-         * Free up any indirection buffers we allocated for DMA purposes. 
-         */
         if (cmd->use_sg)
                 scsi_free_sgtable(cmd->request_buffer, cmd->sglist_len);
-        else if (cmd->request_buffer != req->buffer)
-                kfree(cmd->request_buffer);
 
         /*
          * Zero these out.  They now point to freed memory, and it is
          * dangerous to hang onto the pointers.
          */
-        cmd->buffer  = NULL;
-        cmd->bufflen = 0;
         cmd->request_buffer = NULL;
         cmd->request_bufflen = 0;
 }
@@ -855,11 +810,10 @@ static void scsi_release_buffers(struct scsi_cmnd *cmd)
  *              b) We can just use scsi_requeue_command() here.  This would
  *                 be used if we just wanted to retry, for example.
  */
-void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes,
-                        unsigned int block_bytes)
+void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
 {
         int result = cmd->result;
-        int this_count = cmd->bufflen;
+        int this_count = cmd->request_bufflen;
         request_queue_t *q = cmd->device->request_queue;
         struct request *req = cmd->request;
         int clear_errors = 1;
@@ -867,28 +821,14 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes,
         int sense_valid = 0;
         int sense_deferred = 0;
 
-        /*
-         * Free up any indirection buffers we allocated for DMA purposes. 
-         * For the case of a READ, we need to copy the data out of the
-         * bounce buffer and into the real buffer.
-         */
-        if (cmd->use_sg)
-                scsi_free_sgtable(cmd->buffer, cmd->sglist_len);
-        else if (cmd->buffer != req->buffer) {
-                if (rq_data_dir(req) == READ) {
-                        unsigned long flags;
-                        char *to = bio_kmap_irq(req->bio, &flags);
-                        memcpy(to, cmd->buffer, cmd->bufflen);
-                        bio_kunmap_irq(to, &flags);
-                }
-                kfree(cmd->buffer);
-        }
+        scsi_release_buffers(cmd);
 
         if (result) {
                 sense_valid = scsi_command_normalize_sense(cmd, &sshdr);
                 if (sense_valid)
                         sense_deferred = scsi_sense_is_deferred(&sshdr);
         }
+
         if (blk_pc_request(req)) { /* SG_IO ioctl from block level */
                 req->errors = result;
                 if (result) {
@@ -909,99 +849,73 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes,
         }
 
         /*
-         * Zero these out.  They now point to freed memory, and it is
-         * dangerous to hang onto the pointers.
-         */
-        cmd->buffer  = NULL;
-        cmd->bufflen = 0;
-        cmd->request_buffer = NULL;
-        cmd->request_bufflen = 0;
-
-        /*
          * Next deal with any sectors which we were able to correctly
          * handle.
          */
-        if (good_bytes >= 0) {
-                SCSI_LOG_HLCOMPLETE(1, printk("%ld sectors total, %d bytes done.\n",
-                                              req->nr_sectors, good_bytes));
-                SCSI_LOG_HLCOMPLETE(1, printk("use_sg is %d\n", cmd->use_sg));
+        SCSI_LOG_HLCOMPLETE(1, printk("%ld sectors total, "
+                                      "%d bytes done.\n",
+                                      req->nr_sectors, good_bytes));
+        SCSI_LOG_HLCOMPLETE(1, printk("use_sg is %d\n", cmd->use_sg));
 
-                if (clear_errors)
-                        req->errors = 0;
-                /*
-                 * If multiple sectors are requested in one buffer, then
-                 * they will have been finished off by the first command.
-                 * If not, then we have a multi-buffer command.
-                 *
-                 * If block_bytes != 0, it means we had a medium error
-                 * of some sort, and that we want to mark some number of
-                 * sectors as not uptodate.  Thus we want to inhibit
-                 * requeueing right here - we will requeue down below
-                 * when we handle the bad sectors.
-                 */
+        if (clear_errors)
+                req->errors = 0;
 
-                /*
-                 * If the command completed without error, then either
-                 * finish off the rest of the command, or start a new one.
-                 */
-                if (scsi_end_request(cmd, 1, good_bytes, result == 0) == NULL)
-                        return;
-        }
-        /*
-         * Now, if we were good little boys and girls, Santa left us a request
-         * sense buffer.  We can extract information from this, so we
-         * can choose a block to remap, etc.
+        /* A number of bytes were successfully read.  If there
+         * are leftovers and there is some kind of error
+         * (result != 0), retry the rest.
+         */
+        if (scsi_end_request(cmd, 1, good_bytes, result == 0) == NULL)
+                return;
+
+        /* good_bytes = 0, or (inclusive) there were leftovers and
+         * result = 0, so scsi_end_request couldn't retry.
          */
         if (sense_valid && !sense_deferred) {
                 switch (sshdr.sense_key) {
                 case UNIT_ATTENTION:
                         if (cmd->device->removable) {
-                                /* detected disc change.  set a bit 
+                                /* Detected disc change.  Set a bit
                                  * and quietly refuse further access.
                                  */
                                 cmd->device->changed = 1;
-                                scsi_end_request(cmd, 0,
-                                                this_count, 1);
+                                scsi_end_request(cmd, 0, this_count, 1);
                                 return;
                         } else {
-                                /*
-                                * Must have been a power glitch, or a
-                                * bus reset.  Could not have been a
-                                * media change, so we just retry the
-                                * request and see what happens.  
-                                */
+                                /* Must have been a power glitch, or a
+                                 * bus reset.  Could not have been a
+                                 * media change, so we just retry the
+                                 * request and see what happens.
+                                 */
                                 scsi_requeue_command(q, cmd);
                                 return;
                         }
                         break;
                 case ILLEGAL_REQUEST:
-                        /*
-                        * If we had an ILLEGAL REQUEST returned, then we may
-                        * have performed an unsupported command.  The only
-                        * thing this should be would be a ten byte read where
-                        * only a six byte read was supported.  Also, on a
-                        * system where READ CAPACITY failed, we may have read
-                        * past the end of the disk.
-                        */
+                        /* If we had an ILLEGAL REQUEST returned, then
+                         * we may have performed an unsupported
+                         * command.  The only thing this should be
+                         * would be a ten byte read where only a six
+                         * byte read was supported.  Also, on a system
+                         * where READ CAPACITY failed, we may have
+                         * read past the end of the disk.
+                         */
                         if ((cmd->device->use_10_for_rw &&
                             sshdr.asc == 0x20 && sshdr.ascq == 0x00) &&
                             (cmd->cmnd[0] == READ_10 ||
                              cmd->cmnd[0] == WRITE_10)) {
                                 cmd->device->use_10_for_rw = 0;
-                                /*
-                                 * This will cause a retry with a 6-byte
-                                 * command.
+                                /* This will cause a retry with a
+                                 * 6-byte command.
                                  */
                                 scsi_requeue_command(q, cmd);
-                                result = 0;
+                                return;
                         } else {
                                 scsi_end_request(cmd, 0, this_count, 1);
                                 return;
                         }
                         break;
                 case NOT_READY:
-                        /*
-                         * If the device is in the process of becoming
+                        /* If the device is in the process of becoming
                          * ready, or has a temporary blockage, retry.
                          */
                         if (sshdr.asc == 0x04) {
@@ -1021,7 +935,7 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes,
                         }
                         if (!(req->flags & REQ_QUIET)) {
                                 scmd_printk(KERN_INFO, cmd,
-                                           "Device not ready: ");
+                                            "Device not ready: ");
                                 scsi_print_sense_hdr("", &sshdr);
                         }
                         scsi_end_request(cmd, 0, this_count, 1);
@@ -1029,21 +943,21 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes,
                 case VOLUME_OVERFLOW:
                         if (!(req->flags & REQ_QUIET)) {
                                 scmd_printk(KERN_INFO, cmd,
-                                           "Volume overflow, CDB: ");
-                                __scsi_print_command(cmd->data_cmnd);
+                                            "Volume overflow, CDB: ");
+                                __scsi_print_command(cmd->cmnd);
                                 scsi_print_sense("", cmd);
                         }
-                        scsi_end_request(cmd, 0, block_bytes, 1);
+                        /* See SSC3rXX or current. */
+                        scsi_end_request(cmd, 0, this_count, 1);
                         return;
                 default:
                         break;
                 }
-        }                       /* driver byte != 0 */
+        }
         if (host_byte(result) == DID_RESET) {
-                /*
-                 * Third party bus reset or reset for error
-                 * recovery reasons.  Just retry the request
-                 * and see what happens.  
+                /* Third party bus reset or reset for error recovery
+                 * reasons.  Just retry the request and see what
+                 * happens.
                  */
                 scsi_requeue_command(q, cmd);
                 return;
@@ -1051,21 +965,13 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes,
         if (result) {
                 if (!(req->flags & REQ_QUIET)) {
                         scmd_printk(KERN_INFO, cmd,
-                                   "SCSI error: return code = 0x%x\n", result);
-
+                                    "SCSI error: return code = 0x%08x\n",
+                                    result);
                         if (driver_byte(result) & DRIVER_SENSE)
                                 scsi_print_sense("", cmd);
                 }
-                /*
-                 * Mark a single buffer as not uptodate.  Queue the remainder.
-                 * We sometimes get this cruft in the event that a medium error
-                 * isn't properly reported.
-                 */
-                block_bytes = req->hard_cur_sectors << 9;
-                if (!block_bytes)
-                        block_bytes = req->data_len;
-                scsi_end_request(cmd, 0, block_bytes, 1);
         }
+        scsi_end_request(cmd, 0, this_count, !result);
 }
 EXPORT_SYMBOL(scsi_io_completion);
 
@@ -1169,7 +1075,7 @@ static void scsi_blk_pc_done(struct scsi_cmnd *cmd)
          * successfully. Since this is a REQ_BLOCK_PC command the
          * caller should check the request's errors value
          */
-        scsi_io_completion(cmd, cmd->bufflen, 0);
+        scsi_io_completion(cmd, cmd->request_bufflen);
 }
 
 static void scsi_setup_blk_pc_cmnd(struct scsi_cmnd *cmd)
@@ -2050,6 +1956,7 @@ scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state)
                 switch (oldstate) {
                 case SDEV_CREATED:
                 case SDEV_RUNNING:
+                case SDEV_QUIESCE:
                 case SDEV_OFFLINE:
                 case SDEV_BLOCK:
                         break;
@@ -2060,6 +1967,9 @@ scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state)
 
         case SDEV_DEL:
                 switch (oldstate) {
+                case SDEV_CREATED:
+                case SDEV_RUNNING:
+                case SDEV_OFFLINE:
                 case SDEV_CANCEL:
                         break;
                 default: