5 files changed, 119 insertions, 82 deletions

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 47d3cdd6ddf..94d82cb9662 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1039,9 +1039,6 @@ static int scsi_init_io(struct scsi_cmnd *cmd)
         printk(KERN_ERR "req nr_sec %lu, cur_nr_sec %u\n", req->nr_sectors,
                         req->current_nr_sectors);
 
-        /* release the command and kill it */
-        scsi_release_buffers(cmd);
-        scsi_put_command(cmd);
         return BLKPREP_KILL;
 }
 
@@ -1078,9 +1075,13 @@ static void scsi_blk_pc_done(struct scsi_cmnd *cmd)
         scsi_io_completion(cmd, cmd->request_bufflen);
 }
 
-static int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req)
+int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req)
 {
         struct scsi_cmnd *cmd;
+        int ret = scsi_prep_state_check(sdev, req);
+
+        if (ret != BLKPREP_OK)
+                return ret;
 
         cmd = scsi_get_cmd_from_req(sdev, req);
         if (unlikely(!cmd))
@@ -1126,18 +1127,20 @@ static int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req)
         cmd->done = scsi_blk_pc_done;
         return BLKPREP_OK;
 }
+EXPORT_SYMBOL(scsi_setup_blk_pc_cmnd);
 
 /*
  * Setup a REQ_TYPE_FS command.  These are simple read/write request
  * from filesystems that still need to be translated to SCSI CDBs from
  * the ULD.
  */
-static int scsi_setup_fs_cmnd(struct scsi_device *sdev, struct request *req)
+int scsi_setup_fs_cmnd(struct scsi_device *sdev, struct request *req)
 {
         struct scsi_cmnd *cmd;
-        struct scsi_driver *drv;
-        int ret;
+        int ret = scsi_prep_state_check(sdev, req);
 
+        if (ret != BLKPREP_OK)
+                return ret;
         /*
          * Filesystem requests must transfer data.
          */
@@ -1147,26 +1150,12 @@ static int scsi_setup_fs_cmnd(struct scsi_device *sdev, struct request *req)
         if (unlikely(!cmd))
                 return BLKPREP_DEFER;
 
-        ret = scsi_init_io(cmd);
-        if (unlikely(ret))
-                return ret;
-
-        /*
-         * Initialize the actual SCSI command for this request.
-         */
-        drv = *(struct scsi_driver **)req->rq_disk->private_data;
-        if (unlikely(!drv->init_command(cmd))) {
-                scsi_release_buffers(cmd);
-                scsi_put_command(cmd);
-                return BLKPREP_KILL;
-        }
-
-        return BLKPREP_OK;
+        return scsi_init_io(cmd);
 }
+EXPORT_SYMBOL(scsi_setup_fs_cmnd);
 
-static int scsi_prep_fn(struct request_queue *q, struct request *req)
+int scsi_prep_state_check(struct scsi_device *sdev, struct request *req)
 {
-        struct scsi_device *sdev = q->queuedata;
         int ret = BLKPREP_OK;
 
         /*
@@ -1212,35 +1201,25 @@ static int scsi_prep_fn(struct request_queue *q, struct request *req)
                                 ret = BLKPREP_KILL;
                         break;
                 }
-
-                if (ret != BLKPREP_OK)
-                        goto out;
         }
+        return ret;
+}
+EXPORT_SYMBOL(scsi_prep_state_check);
 
-        switch (req->cmd_type) {
-        case REQ_TYPE_BLOCK_PC:
-                ret = scsi_setup_blk_pc_cmnd(sdev, req);
-                break;
-        case REQ_TYPE_FS:
-                ret = scsi_setup_fs_cmnd(sdev, req);
-                break;
-        default:
-                /*
-                 * All other command types are not supported.
-                 *
-                 * Note that these days the SCSI subsystem does not use
-                 * REQ_TYPE_SPECIAL requests anymore.  These are only used
-                 * (directly or via blk_insert_request) by non-SCSI drivers.
-                 */
-                blk_dump_rq_flags(req, "SCSI bad req");
-                ret = BLKPREP_KILL;
-                break;
-        }
+int scsi_prep_return(struct request_queue *q, struct request *req, int ret)
+{
+        struct scsi_device *sdev = q->queuedata;
 
- out:
         switch (ret) {
         case BLKPREP_KILL:
                 req->errors = DID_NO_CONNECT << 16;
+                /* release the command and kill it */
+                if (req->special) {
+                        struct scsi_cmnd *cmd = req->special;
+                        scsi_release_buffers(cmd);
+                        scsi_put_command(cmd);
+                        req->special = NULL;
+                }
                 break;
         case BLKPREP_DEFER:
                 /*
@@ -1257,6 +1236,17 @@ static int scsi_prep_fn(struct request_queue *q, struct request *req)
 
         return ret;
 }
+EXPORT_SYMBOL(scsi_prep_return);
+
+static int scsi_prep_fn(struct request_queue *q, struct request *req)
+{
+        struct scsi_device *sdev = q->queuedata;
+        int ret = BLKPREP_KILL;
+
+        if (req->cmd_type == REQ_TYPE_BLOCK_PC)
+                ret = scsi_setup_blk_pc_cmnd(sdev, req);
+        return scsi_prep_return(q, req, ret);
+}
 
 /*
  * scsi_dev_queue_ready: if we can send requests to sdev, return 1 else
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 2c6116fd457..38a41415004 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -240,7 +240,6 @@ static struct scsi_driver sd_template = {
                 .shutdown       = sd_shutdown,
         },
         .rescan                 = sd_rescan,
-        .init_command           = sd_init_command,
 };
 
 /*
@@ -331,14 +330,31 @@ static void scsi_disk_put(struct scsi_disk *sdkp)
  *
  *      Returns 1 if successful and 0 if error (or cannot be done now).
  **/
-static int sd_init_command(struct scsi_cmnd * SCpnt)
+static int sd_prep_fn(struct request_queue *q, struct request *rq)
 {
-        struct scsi_device *sdp = SCpnt->device;
-        struct request *rq = SCpnt->request;
+        struct scsi_cmnd *SCpnt;
+        struct scsi_device *sdp = q->queuedata;
         struct gendisk *disk = rq->rq_disk;
         sector_t block = rq->sector;
-        unsigned int this_count = SCpnt->request_bufflen >> 9;
+        unsigned int this_count = rq->nr_sectors;
         unsigned int timeout = sdp->timeout;
+        int ret;
+
+        if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
+                ret = scsi_setup_blk_pc_cmnd(sdp, rq);
+                goto out;
+        } else if (rq->cmd_type != REQ_TYPE_FS) {
+                ret = BLKPREP_KILL;
+                goto out;
+        }
+        ret = scsi_setup_fs_cmnd(sdp, rq);
+        if (ret != BLKPREP_OK)
+                goto out;
+        SCpnt = rq->special;
+
+        /* from here on until we're complete, any goto out
+         * is used for a killable error condition */
+        ret = BLKPREP_KILL;
 
         SCSI_LOG_HLQUEUE(1, scmd_printk(KERN_INFO, SCpnt,
                                         "sd_init_command: block=%llu, "
@@ -353,7 +369,7 @@ static int sd_init_command(struct scsi_cmnd * SCpnt)
                                                 rq->nr_sectors));
                 SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
                                                 "Retry with 0x%p\n", SCpnt));
-                return 0;
+                goto out;
         }
 
         if (sdp->changed) {
@@ -362,8 +378,9 @@ static int sd_init_command(struct scsi_cmnd * SCpnt)
                  * the changed bit has been reset
                  */
                 /* printk("SCSI disk has been changed. Prohibiting further I/O.\n"); */
-                return 0;
+                goto out;
         }
+
         SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt, "block=%llu\n",
                                         (unsigned long long)block));
 
@@ -382,7 +399,7 @@ static int sd_init_command(struct scsi_cmnd * SCpnt)
                 if ((block & 1) || (rq->nr_sectors & 1)) {
                         scmd_printk(KERN_ERR, SCpnt,
                                     "Bad block number requested\n");
-                        return 0;
+                        goto out;
                 } else {
                         block = block >> 1;
                         this_count = this_count >> 1;
@@ -392,7 +409,7 @@ static int sd_init_command(struct scsi_cmnd * SCpnt)
                 if ((block & 3) || (rq->nr_sectors & 3)) {
                         scmd_printk(KERN_ERR, SCpnt,
                                     "Bad block number requested\n");
-                        return 0;
+                        goto out;
                 } else {
                         block = block >> 2;
                         this_count = this_count >> 2;
@@ -402,7 +419,7 @@ static int sd_init_command(struct scsi_cmnd * SCpnt)
                 if ((block & 7) || (rq->nr_sectors & 7)) {
                         scmd_printk(KERN_ERR, SCpnt,
                                     "Bad block number requested\n");
-                        return 0;
+                        goto out;
                 } else {
                         block = block >> 3;
                         this_count = this_count >> 3;
@@ -410,7 +427,7 @@ static int sd_init_command(struct scsi_cmnd * SCpnt)
         }
         if (rq_data_dir(rq) == WRITE) {
                 if (!sdp->writeable) {
-                        return 0;
+                        goto out;
                 }
                 SCpnt->cmnd[0] = WRITE_6;
                 SCpnt->sc_data_direction = DMA_TO_DEVICE;
@@ -419,7 +436,7 @@ static int sd_init_command(struct scsi_cmnd * SCpnt)
                 SCpnt->sc_data_direction = DMA_FROM_DEVICE;
         } else {
                 scmd_printk(KERN_ERR, SCpnt, "Unknown command %x\n", rq->cmd_flags);
-                return 0;
+                goto out;
         }
 
         SCSI_LOG_HLQUEUE(2, scmd_printk(KERN_INFO, SCpnt,
@@ -470,7 +487,7 @@ static int sd_init_command(struct scsi_cmnd * SCpnt)
                          */
                         scmd_printk(KERN_ERR, SCpnt,
                                     "FUA write on READ/WRITE(6) drive\n");
-                        return 0;
+                        goto out;
                 }
 
                 SCpnt->cmnd[1] |= (unsigned char) ((block >> 16) & 0x1f);
@@ -501,7 +518,9 @@ static int sd_init_command(struct scsi_cmnd * SCpnt)
          * This indicates that the command is ready from our end to be
          * queued.
          */
-        return 1;
+        ret = BLKPREP_OK;
+ out:
+        return scsi_prep_return(q, rq, ret);
 }
 
 /**
@@ -1669,6 +1688,7 @@ static int sd_probe(struct device *dev)
 
         sd_revalidate_disk(gd);
 
+        blk_queue_prep_rq(sdp->request_queue, sd_prep_fn);
         blk_queue_issue_flush_fn(sdp->request_queue, sd_issue_flush);
 
         gd->driverfs_dev = &sdp->sdev_gendev;
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index 902eb11ffe8..a0c4e13d4da 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -78,7 +78,6 @@ MODULE_ALIAS_SCSI_DEVICE(TYPE_WORM);
 
 static int sr_probe(struct device *);
 static int sr_remove(struct device *);
-static int sr_init_command(struct scsi_cmnd *);
 
 static struct scsi_driver sr_template = {
         .owner                  = THIS_MODULE,
@@ -87,7 +86,6 @@ static struct scsi_driver sr_template = {
                 .probe          = sr_probe,
                 .remove         = sr_remove,
         },
-        .init_command           = sr_init_command,
 };
 
 static unsigned long sr_index_bits[SR_DISKS / BITS_PER_LONG];
@@ -296,19 +294,39 @@ static void rw_intr(struct scsi_cmnd * SCpnt)
         scsi_io_completion(SCpnt, good_bytes);
 }
 
-static int sr_init_command(struct scsi_cmnd * SCpnt)
+static int sr_prep_fn(struct request_queue *q, struct request *rq)
 {
         int block=0, this_count, s_size, timeout = SR_TIMEOUT;
-        struct scsi_cd *cd = scsi_cd(SCpnt->request->rq_disk);
+        struct scsi_cd *cd;
+        struct scsi_cmnd *SCpnt;
+        struct scsi_device *sdp = q->queuedata;
+        int ret;
+
+        if (rq->cmd_type == REQ_TYPE_BLOCK_PC) {
+                ret = scsi_setup_blk_pc_cmnd(sdp, rq);
+                goto out;
+        } else if (rq->cmd_type != REQ_TYPE_FS) {
+                ret = BLKPREP_KILL;
+                goto out;
+        }
+        ret = scsi_setup_fs_cmnd(sdp, rq);
+        if (ret != BLKPREP_OK)
+                goto out;
+        SCpnt = rq->special;
+        cd = scsi_cd(rq->rq_disk);
+
+        /* from here on until we're complete, any goto out
+         * is used for a killable error condition */
+        ret = BLKPREP_KILL;
 
         SCSI_LOG_HLQUEUE(1, printk("Doing sr request, dev = %s, block = %d\n",
                                 cd->disk->disk_name, block));
 
         if (!cd->device || !scsi_device_online(cd->device)) {
                 SCSI_LOG_HLQUEUE(2, printk("Finishing %ld sectors\n",
-                                        SCpnt->request->nr_sectors));
+                                        rq->nr_sectors));
                 SCSI_LOG_HLQUEUE(2, printk("Retry with 0x%p\n", SCpnt));
-                return 0;
+                goto out;
         }
 
         if (cd->device->changed) {
@@ -316,7 +334,7 @@ static int sr_init_command(struct scsi_cmnd * SCpnt)
                  * quietly refuse to do anything to a changed disc until the
                  * changed bit has been reset
                  */
-                return 0;
+                goto out;
         }
 
         /*
@@ -333,21 +351,21 @@ static int sr_init_command(struct scsi_cmnd * SCpnt)
 
         if (s_size != 512 && s_size != 1024 && s_size != 2048) {
                 scmd_printk(KERN_ERR, SCpnt, "bad sector size %d\n", s_size);
-                return 0;
+                goto out;
         }
 
-        if (rq_data_dir(SCpnt->request) == WRITE) {
+        if (rq_data_dir(rq) == WRITE) {
                 if (!cd->device->writeable)
-                        return 0;
+                        goto out;
                 SCpnt->cmnd[0] = WRITE_10;
                 SCpnt->sc_data_direction = DMA_TO_DEVICE;
                 cd->cdi.media_written = 1;
-        } else if (rq_data_dir(SCpnt->request) == READ) {
+        } else if (rq_data_dir(rq) == READ) {
                 SCpnt->cmnd[0] = READ_10;
                 SCpnt->sc_data_direction = DMA_FROM_DEVICE;
         } else {
-                blk_dump_rq_flags(SCpnt->request, "Unknown sr command");
-                return 0;
+                blk_dump_rq_flags(rq, "Unknown sr command");
+                goto out;
         }
 
         {
@@ -368,10 +386,10 @@ static int sr_init_command(struct scsi_cmnd * SCpnt)
         /*
          * request doesn't start on hw block boundary, add scatter pads
          */
-        if (((unsigned int)SCpnt->request->sector % (s_size >> 9)) ||
+        if (((unsigned int)rq->sector % (s_size >> 9)) ||
             (SCpnt->request_bufflen % s_size)) {
                 scmd_printk(KERN_NOTICE, SCpnt, "unaligned transfer\n");
-                return 0;
+                goto out;
         }
 
         this_count = (SCpnt->request_bufflen >> 9) / (s_size >> 9);
@@ -379,12 +397,12 @@ static int sr_init_command(struct scsi_cmnd * SCpnt)
 
         SCSI_LOG_HLQUEUE(2, printk("%s : %s %d/%ld 512 byte blocks.\n",
                                 cd->cdi.name,
-                                (rq_data_dir(SCpnt->request) == WRITE) ?
+                                (rq_data_dir(rq) == WRITE) ?
                                         "writing" : "reading",
-                                this_count, SCpnt->request->nr_sectors));
+                                this_count, rq->nr_sectors));
 
         SCpnt->cmnd[1] = 0;
-        block = (unsigned int)SCpnt->request->sector / (s_size >> 9);
+        block = (unsigned int)rq->sector / (s_size >> 9);
 
         if (this_count > 0xffff) {
                 this_count = 0xffff;
@@ -419,7 +437,9 @@ static int sr_init_command(struct scsi_cmnd * SCpnt)
          * This indicates that the command is ready from our end to be
          * queued.
          */
-        return 1;
+        ret = BLKPREP_OK;
+ out:
+        return scsi_prep_return(q, rq, ret);
 }
 
 static int sr_block_open(struct inode *inode, struct file *file)
@@ -590,6 +610,7 @@ static int sr_probe(struct device *dev)
 
         /* FIXME: need to handle a get_capabilities failure properly ?? */
         get_capabilities(cd);
+        blk_queue_prep_rq(sdev->request_queue, sr_prep_fn);
         sr_vendor_init(cd);
 
         disk->driverfs_dev = &sdev->sdev_gendev;
diff --git a/include/scsi/scsi_driver.h b/include/scsi/scsi_driver.h
index 3465f31a21c..56a304709fd 100644
--- a/include/scsi/scsi_driver.h
+++ b/include/scsi/scsi_driver.h
@@ -5,13 +5,15 @@
 
 struct module;
 struct scsi_cmnd;
+struct scsi_device;
+struct request;
+struct request_queue;
 
 
 struct scsi_driver {
         struct module           *owner;
         struct device_driver    gendrv;
 
-        int (*init_command)(struct scsi_cmnd *);
         void (*rescan)(struct device *);
 };
 #define to_scsi_driver(drv) \
@@ -25,4 +27,9 @@ extern int scsi_register_interface(struct class_interface *);
 #define scsi_unregister_interface(intf) \
         class_interface_unregister(intf)
 
+int scsi_setup_blk_pc_cmnd(struct scsi_device *sdev, struct request *req);
+int scsi_setup_fs_cmnd(struct scsi_device *sdev, struct request *req);
+int scsi_prep_state_check(struct scsi_device *sdev, struct request *req);
+int scsi_prep_return(struct request_queue *q, struct request *req, int ret);
+
 #endif /* _SCSI_SCSI_DRIVER_H */
diff --git a/include/scsi/sd.h b/include/scsi/sd.h
index ce02ad1f518..aa1e7161301 100644
--- a/include/scsi/sd.h
+++ b/include/scsi/sd.h
@@ -55,7 +55,6 @@ static void sd_shutdown(struct device *dev);
 static int sd_suspend(struct device *dev, pm_message_t state);
 static int sd_resume(struct device *dev);
 static void sd_rescan(struct device *);
-static int  sd_init_command(struct scsi_cmnd *);
 static void sd_read_capacity(struct scsi_disk *sdkp, unsigned char *buffer);
 static void scsi_disk_release(struct class_device *cdev);
 static void sd_print_sense_hdr(struct scsi_disk *, struct scsi_sense_hdr *);