1 files changed, 45 insertions, 40 deletions

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 3d3ad7d1b779..32d4d8d7b9f3 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -102,6 +102,7 @@ struct scsi_disk {
         u8              write_prot;
         unsigned        WCE : 1;        /* state of disk WCE bit */
         unsigned        RCD : 1;        /* state of disk RCD bit, unused */
+        unsigned        DPOFUA : 1;     /* state of disk DPOFUA bit */
 };
 
 static DEFINE_IDR(sd_index_idr);
@@ -121,8 +122,7 @@ static void sd_shutdown(struct device *dev);
 static void sd_rescan(struct device *);
 static int sd_init_command(struct scsi_cmnd *);
 static int sd_issue_flush(struct device *, sector_t *);
-static void sd_end_flush(request_queue_t *, struct request *);
-static int sd_prepare_flush(request_queue_t *, struct request *);
+static void sd_prepare_flush(request_queue_t *, struct request *);
 static void sd_read_capacity(struct scsi_disk *sdkp, char *diskname,
                              unsigned char *buffer);
 
@@ -137,8 +137,6 @@ static struct scsi_driver sd_template = {
         .rescan                 = sd_rescan,
         .init_command           = sd_init_command,
         .issue_flush            = sd_issue_flush,
-        .prepare_flush          = sd_prepare_flush,
-        .end_flush              = sd_end_flush,
 };
 
 /*
@@ -346,6 +344,7 @@ static int sd_init_command(struct scsi_cmnd * SCpnt)
         
         if (block > 0xffffffff) {
                 SCpnt->cmnd[0] += READ_16 - READ_6;
+                SCpnt->cmnd[1] |= blk_fua_rq(rq) ? 0x8 : 0;
                 SCpnt->cmnd[2] = sizeof(block) > 4 ? (unsigned char) (block >> 56) & 0xff : 0;
                 SCpnt->cmnd[3] = sizeof(block) > 4 ? (unsigned char) (block >> 48) & 0xff : 0;
                 SCpnt->cmnd[4] = sizeof(block) > 4 ? (unsigned char) (block >> 40) & 0xff : 0;
@@ -365,6 +364,7 @@ static int sd_init_command(struct scsi_cmnd * SCpnt)
                         this_count = 0xffff;
 
                 SCpnt->cmnd[0] += READ_10 - READ_6;
+                SCpnt->cmnd[1] |= blk_fua_rq(rq) ? 0x8 : 0;
                 SCpnt->cmnd[2] = (unsigned char) (block >> 24) & 0xff;
                 SCpnt->cmnd[3] = (unsigned char) (block >> 16) & 0xff;
                 SCpnt->cmnd[4] = (unsigned char) (block >> 8) & 0xff;
@@ -373,6 +373,17 @@ static int sd_init_command(struct scsi_cmnd * SCpnt)
                 SCpnt->cmnd[7] = (unsigned char) (this_count >> 8) & 0xff;
                 SCpnt->cmnd[8] = (unsigned char) this_count & 0xff;
         } else {
+                if (unlikely(blk_fua_rq(rq))) {
+                        /*
+                         * This happens only if this drive failed
+                         * 10byte rw command with ILLEGAL_REQUEST
+                         * during operation and thus turned off
+                         * use_10_for_rw.
+                         */
+                        printk(KERN_ERR "sd: FUA write on READ/WRITE(6) drive\n");
+                        return 0;
+                }
+
                 SCpnt->cmnd[1] |= (unsigned char) ((block >> 16) & 0x1f);
                 SCpnt->cmnd[2] = (unsigned char) ((block >> 8) & 0xff);
                 SCpnt->cmnd[3] = (unsigned char) block & 0xff;
@@ -729,42 +740,13 @@ static int sd_issue_flush(struct device *dev, sector_t *error_sector)
         return ret;
 }
 
-static void sd_end_flush(request_queue_t *q, struct request *flush_rq)
-{
-        struct request *rq = flush_rq->end_io_data;
-        struct scsi_cmnd *cmd = rq->special;
-        unsigned int bytes = rq->hard_nr_sectors << 9;
-
-        if (!flush_rq->errors) {
-                spin_unlock(q->queue_lock);
-                scsi_io_completion(cmd, bytes, 0);
-                spin_lock(q->queue_lock);
-        } else if (blk_barrier_postflush(rq)) {
-                spin_unlock(q->queue_lock);
-                scsi_io_completion(cmd, 0, bytes);
-                spin_lock(q->queue_lock);
-        } else {
-                /*
-                 * force journal abort of barriers
-                 */
-                end_that_request_first(rq, -EOPNOTSUPP, rq->hard_nr_sectors);
-                end_that_request_last(rq);
-        }
-}
-
-static int sd_prepare_flush(request_queue_t *q, struct request *rq)
+static void sd_prepare_flush(request_queue_t *q, struct request *rq)
 {
-        struct scsi_device *sdev = q->queuedata;
-        struct scsi_disk *sdkp = dev_get_drvdata(&sdev->sdev_gendev);
-
-        if (!sdkp || !sdkp->WCE)
-                return 0;
-
         memset(rq->cmd, 0, sizeof(rq->cmd));
-        rq->flags |= REQ_BLOCK_PC | REQ_SOFTBARRIER;
+        rq->flags |= REQ_BLOCK_PC;
         rq->timeout = SD_TIMEOUT;
         rq->cmd[0] = SYNCHRONIZE_CACHE;
-        return 1;
+        rq->cmd_len = 10;
 }
 
 static void sd_rescan(struct device *dev)
@@ -1427,10 +1409,18 @@ sd_read_cache_type(struct scsi_disk *sdkp, char *diskname,
                         sdkp->RCD = 0;
                 }
 
+                sdkp->DPOFUA = (data.device_specific & 0x10) != 0;
+                if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) {
+                        printk(KERN_NOTICE "SCSI device %s: uses "
+                               "READ/WRITE(6), disabling FUA\n", diskname);
+                        sdkp->DPOFUA = 0;
+                }
+
                 ct =  sdkp->RCD + 2*sdkp->WCE;
 
-                printk(KERN_NOTICE "SCSI device %s: drive cache: %s\n",
-                       diskname, types[ct]);
+                printk(KERN_NOTICE "SCSI device %s: drive cache: %s%s\n",
+                       diskname, types[ct],
+                       sdkp->DPOFUA ? " w/ FUA" : "");
 
                 return;
         }
@@ -1462,6 +1452,7 @@ static int sd_revalidate_disk(struct gendisk *disk)
         struct scsi_disk *sdkp = scsi_disk(disk);
         struct scsi_device *sdp = sdkp->device;
         unsigned char *buffer;
+        unsigned ordered;
 
         SCSI_LOG_HLQUEUE(3, printk("sd_revalidate_disk: disk=%s\n", disk->disk_name));
 
@@ -1498,7 +1489,21 @@ static int sd_revalidate_disk(struct gendisk *disk)
                 sd_read_write_protect_flag(sdkp, disk->disk_name, buffer);
                 sd_read_cache_type(sdkp, disk->disk_name, buffer);
         }
-                
+
+        /*
+         * We now have all cache related info, determine how we deal
+         * with ordered requests.  Note that as the current SCSI
+         * dispatch function can alter request order, we cannot use
+         * QUEUE_ORDERED_TAG_* even when ordered tag is supported.
+         */
+        if (sdkp->WCE)
+                ordered = sdkp->DPOFUA
+                        ? QUEUE_ORDERED_DRAIN_FUA : QUEUE_ORDERED_DRAIN_FLUSH;
+        else
+                ordered = QUEUE_ORDERED_DRAIN;
+
+        blk_queue_ordered(sdkp->disk->queue, ordered, sd_prepare_flush);
+
         set_capacity(disk, sdkp->capacity);
         kfree(buffer);
 
@@ -1598,6 +1603,7 @@ static int sd_probe(struct device *dev)
         strcpy(gd->devfs_name, sdp->devfs_name);
 
         gd->private_data = &sdkp->driver;
+        gd->queue = sdkp->device->request_queue;
 
         sd_revalidate_disk(gd);
 
@@ -1605,7 +1611,6 @@ static int sd_probe(struct device *dev)
         gd->flags = GENHD_FL_DRIVERFS;
         if (sdp->removable)
                 gd->flags |= GENHD_FL_REMOVABLE;
-        gd->queue = sdkp->device->request_queue;
 
         dev_set_drvdata(dev, sdkp);
         add_disk(gd);