[SCSI] sd: disentangle barriers in SCSI

Our current implementation has a generic set of barrier functions that
go through the SCSI driver model.  Realistically, this is unnecessary,
because the only device that can use barriers (sd) can set the flush
functions up at probe or revalidate time.  This patch pulls the barrier
functions out of the mid layer and scsi driver model and relocates them
directly in sd.

Acked-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 21c075d44db131726e002ead6e4e707c932a2ee8..a417a6ff9f97aee1e1a044c2c736c48f62722540 100644 (file)
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1038,22 +1038,6 @@ static int scsi_init_io(struct scsi_cmnd *cmd)
        return BLKPREP_KILL;
 }
 
-static int scsi_issue_flush_fn(struct request_queue *q, struct gendisk *disk,
-                              sector_t *error_sector)
-{
-       struct scsi_device *sdev = q->queuedata;
-       struct scsi_driver *drv;
-
-       if (sdev->sdev_state != SDEV_RUNNING)
-               return -ENXIO;
-
-       drv = *(struct scsi_driver **) disk->private_data;
-       if (drv->issue_flush)
-               return drv->issue_flush(&sdev->sdev_gendev, error_sector);
-
-       return -EOPNOTSUPP;
-}
-
 static struct scsi_cmnd *scsi_get_cmd_from_req(struct scsi_device *sdev,
                struct request *req)
 {
@@ -1596,7 +1580,6 @@ struct request_queue *scsi_alloc_queue(struct scsi_device *sdev)
                return NULL;
 
        blk_queue_prep_rq(q, scsi_prep_fn);
-       blk_queue_issue_flush_fn(q, scsi_issue_flush_fn);
        blk_queue_softirq_done(q, scsi_softirq_done);
        return q;
 }

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index e21c7142a3ea957bee7c58cde38e58fcfea925a3..2c6116fd457818a27be8552119425030a6143e68 100644 (file)
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -241,7 +241,6 @@ static struct scsi_driver sd_template = {
        },
        .rescan                 = sd_rescan,
        .init_command           = sd_init_command,
-       .issue_flush            = sd_issue_flush,
 };
 
 /*
@@ -800,10 +799,17 @@ static int sd_sync_cache(struct scsi_disk *sdkp)
        return 0;
 }
 
-static int sd_issue_flush(struct device *dev, sector_t *error_sector)
+static int sd_issue_flush(struct request_queue *q, struct gendisk *disk,
+                         sector_t *error_sector)
 {
        int ret = 0;
-       struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
+       struct scsi_device *sdp = q->queuedata;
+       struct scsi_disk *sdkp;
+
+       if (sdp->sdev_state != SDEV_RUNNING)
+               return -ENXIO;
+
+       sdkp = scsi_disk_get_from_dev(&sdp->sdev_gendev);
 
        if (!sdkp)
                return -ENODEV;
@@ -1663,6 +1669,8 @@ static int sd_probe(struct device *dev)
 
        sd_revalidate_disk(gd);
 
+       blk_queue_issue_flush_fn(sdp->request_queue, sd_issue_flush);
+
        gd->driverfs_dev = &sdp->sdev_gendev;
        gd->flags = GENHD_FL_DRIVERFS;
        if (sdp->removable)

diff --git a/include/scsi/scsi_driver.h b/include/scsi/scsi_driver.h
index 02e26c1672bf25edef324b65ff585969b899d642..3465f31a21c4c5bb83980db6dcf6ab721ff0678e 100644 (file)
--- a/include/scsi/scsi_driver.h
+++ b/include/scsi/scsi_driver.h
@@ -13,8 +13,6 @@ struct scsi_driver {
 
        int (*init_command)(struct scsi_cmnd *);
        void (*rescan)(struct device *);
-       int (*issue_flush)(struct device *, sector_t *);
-       int (*prepare_flush)(struct request_queue *, struct request *);
 };
 #define to_scsi_driver(drv) \
        container_of((drv), struct scsi_driver, gendrv)

diff --git a/include/scsi/sd.h b/include/scsi/sd.h
index 78583fee0ab2abbc70a721df3b8a1b62c2e497d3..ce02ad1f518569cedefdb3f76fff5d8b055c0dba 100644 (file)
--- a/include/scsi/sd.h
+++ b/include/scsi/sd.h
@@ -56,8 +56,6 @@ 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 int  sd_issue_flush(struct device *, sector_t *);
-static void sd_prepare_flush(struct request_queue *, struct request *);
 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 *);