Merge master.kernel.org:/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
[sfrench/cifs-2.6.git] / drivers / scsi / scsi_lib.c
index 08af9aae7df38e22f86c6d17da7dc4fc491edb72..743f67ed76400e1433d8f4bbd00d2bf91bd8fbca 100644 (file)
@@ -82,7 +82,7 @@ static void scsi_unprep_request(struct request *req)
 {
        struct scsi_cmnd *cmd = req->special;
 
-       req->flags &= ~REQ_DONTPREP;
+       req->cmd_flags &= ~REQ_DONTPREP;
        req->special = NULL;
 
        scsi_put_command(cmd);
@@ -196,7 +196,8 @@ int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
        req->sense_len = 0;
        req->retries = retries;
        req->timeout = timeout;
-       req->flags |= flags | REQ_BLOCK_PC | REQ_SPECIAL | REQ_QUIET;
+       req->cmd_type = REQ_TYPE_BLOCK_PC;
+       req->cmd_flags |= flags | REQ_QUIET | REQ_PREEMPT;
 
        /*
         * head injection *required* here otherwise quiesce won't work
@@ -397,7 +398,8 @@ int scsi_execute_async(struct scsi_device *sdev, const unsigned char *cmd,
        req = blk_get_request(sdev->request_queue, write, gfp);
        if (!req)
                goto free_sense;
-       req->flags |= REQ_BLOCK_PC | REQ_QUIET;
+       req->cmd_type = REQ_TYPE_BLOCK_PC;
+       req->cmd_flags |= REQ_QUIET;
 
        if (use_sg)
                err = scsi_req_map_sg(req, buffer, use_sg, bufflen, gfp);
@@ -424,7 +426,7 @@ int scsi_execute_async(struct scsi_device *sdev, const unsigned char *cmd,
 free_req:
        blk_put_request(req);
 free_sense:
-       kfree(sioc);
+       kmem_cache_free(scsi_io_context_cache, sioc);
        return DRIVER_ERROR << 24;
 }
 EXPORT_SYMBOL_GPL(scsi_execute_async);
@@ -436,60 +438,16 @@ 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 +553,15 @@ 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 +773,13 @@ 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;
 }
@@ -858,7 +815,7 @@ static void scsi_release_buffers(struct scsi_cmnd *cmd)
 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;
@@ -866,28 +823,14 @@ 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) {
@@ -907,15 +850,6 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
                        req->data_len = cmd->resid;
        }
 
-       /*
-        * 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.
@@ -1001,7 +935,7 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
                                        break;
                                }
                        }
-                       if (!(req->flags & REQ_QUIET)) {
+                       if (!(req->cmd_flags & REQ_QUIET)) {
                                scmd_printk(KERN_INFO, cmd,
                                            "Device not ready: ");
                                scsi_print_sense_hdr("", &sshdr);
@@ -1009,10 +943,10 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
                        scsi_end_request(cmd, 0, this_count, 1);
                        return;
                case VOLUME_OVERFLOW:
-                       if (!(req->flags & REQ_QUIET)) {
+                       if (!(req->cmd_flags & REQ_QUIET)) {
                                scmd_printk(KERN_INFO, cmd,
                                            "Volume overflow, CDB: ");
-                               __scsi_print_command(cmd->data_cmnd);
+                               __scsi_print_command(cmd->cmnd);
                                scsi_print_sense("", cmd);
                        }
                        /* See SSC3rXX or current. */
@@ -1031,7 +965,7 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
                return;
        }
        if (result) {
-               if (!(req->flags & REQ_QUIET)) {
+               if (!(req->cmd_flags & REQ_QUIET)) {
                        scmd_printk(KERN_INFO, cmd,
                                    "SCSI error: return code = 0x%08x\n",
                                    result);
@@ -1063,7 +997,7 @@ static int scsi_init_io(struct scsi_cmnd *cmd)
        /*
         * if this is a rq->data based REQ_BLOCK_PC, setup for a non-sg xfer
         */
-       if ((req->flags & REQ_BLOCK_PC) && !req->bio) {
+       if (blk_pc_request(req) && !req->bio) {
                cmd->request_bufflen = req->data_len;
                cmd->request_buffer = req->data;
                req->buffer = req->data;
@@ -1143,7 +1077,7 @@ 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);
+       scsi_io_completion(cmd, cmd->request_bufflen);
 }
 
 static void scsi_setup_blk_pc_cmnd(struct scsi_cmnd *cmd)
@@ -1207,13 +1141,12 @@ static int scsi_prep_fn(struct request_queue *q, struct request *req)
         * these two cases differently.  We differentiate by looking
         * at request->cmd, as this tells us the real story.
         */
-       if (req->flags & REQ_SPECIAL && req->special) {
+       if (blk_special_request(req) && req->special)
                cmd = req->special;
-       } else if (req->flags & (REQ_CMD | REQ_BLOCK_PC)) {
-
-               if(unlikely(specials_only) && !(req->flags & REQ_SPECIAL)) {
-                       if(specials_only == SDEV_QUIESCE ||
-                                       specials_only == SDEV_BLOCK)
+       else if (blk_pc_request(req) || blk_fs_request(req)) {
+               if (unlikely(specials_only) && !(req->cmd_flags & REQ_PREEMPT)){
+                       if (specials_only == SDEV_QUIESCE ||
+                           specials_only == SDEV_BLOCK)
                                goto defer;
                        
                        sdev_printk(KERN_ERR, sdev,
@@ -1221,7 +1154,6 @@ static int scsi_prep_fn(struct request_queue *q, struct request *req)
                        goto kill;
                }
                        
-                       
                /*
                 * Now try and find a command block that we can use.
                 */
@@ -1252,7 +1184,7 @@ static int scsi_prep_fn(struct request_queue *q, struct request *req)
         * lock.  We hope REQ_STARTED prevents anything untoward from
         * happening now.
         */
-       if (req->flags & (REQ_CMD | REQ_BLOCK_PC)) {
+       if (blk_fs_request(req) || blk_pc_request(req)) {
                int ret;
 
                /*
@@ -1284,7 +1216,7 @@ static int scsi_prep_fn(struct request_queue *q, struct request *req)
                /*
                 * Initialize the actual SCSI command for this request.
                 */
-               if (req->flags & REQ_BLOCK_PC) {
+               if (blk_pc_request(req)) {
                        scsi_setup_blk_pc_cmnd(cmd);
                } else if (req->rq_disk) {
                        struct scsi_driver *drv;
@@ -1301,7 +1233,7 @@ static int scsi_prep_fn(struct request_queue *q, struct request *req)
        /*
         * The request is now prepped, no need to come back here
         */
-       req->flags |= REQ_DONTPREP;
+       req->cmd_flags |= REQ_DONTPREP;
        return BLKPREP_OK;
 
  defer:
@@ -1522,8 +1454,9 @@ static void scsi_request_fn(struct request_queue *q)
                if (unlikely(cmd == NULL)) {
                        printk(KERN_CRIT "impossible request in %s.\n"
                                         "please mail a stack trace to "
-                                        "linux-scsi@vger.kernel.org",
+                                        "linux-scsi@vger.kernel.org\n",
                                         __FUNCTION__);
+                       blk_dump_rq_flags(req, "foo");
                        BUG();
                }
                spin_lock(shost->host_lock);