block: convert blkdev_issue_flush() to use empty barriers

Then we can get rid of ->issue_flush_fn() and all the driver private
implementations of that.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

14 files changed, 0 insertions, 306 deletions

diff --git a/drivers/block/ps3disk.c b/drivers/block/ps3disk.c
index 06d0552cf49c..e354bfc070e1 100644
--- a/drivers/block/ps3disk.c
+++ b/drivers/block/ps3disk.c
@@ -414,26 +414,6 @@ static void ps3disk_prepare_flush(struct request_queue *q, struct request *req)
         req->cmd_type = REQ_TYPE_FLUSH;
 }
 
-static int ps3disk_issue_flush(struct request_queue *q, struct gendisk *gendisk,
-                               sector_t *sector)
-{
-        struct ps3_storage_device *dev = q->queuedata;
-        struct request *req;
-        int res;
-
-        dev_dbg(&dev->sbd.core, "%s:%u\n", __func__, __LINE__);
-
-        req = blk_get_request(q, WRITE, __GFP_WAIT);
-        ps3disk_prepare_flush(q, req);
-        res = blk_execute_rq(q, gendisk, req, 0);
-        if (res)
-                dev_err(&dev->sbd.core, "%s:%u: flush request failed %d\n",
-                        __func__, __LINE__, res);
-        blk_put_request(req);
-        return res;
-}
-
-
 static unsigned long ps3disk_mask;
 
 static DEFINE_MUTEX(ps3disk_mask_mutex);
@@ -506,7 +486,6 @@ static int __devinit ps3disk_probe(struct ps3_system_bus_device *_dev)
         blk_queue_dma_alignment(queue, dev->blk_size-1);
         blk_queue_hardsect_size(queue, dev->blk_size);
 
-        blk_queue_issue_flush_fn(queue, ps3disk_issue_flush);
         blk_queue_ordered(queue, QUEUE_ORDERED_DRAIN_FLUSH,
                           ps3disk_prepare_flush);
 
diff --git a/drivers/ide/ide-disk.c b/drivers/ide/ide-disk.c
index 4754769eda97..92177ca48b4d 100644
--- a/drivers/ide/ide-disk.c
+++ b/drivers/ide/ide-disk.c
@@ -716,32 +716,6 @@ static void idedisk_prepare_flush(struct request_queue *q, struct request *rq)
         rq->buffer = rq->cmd;
 }
 
-static int idedisk_issue_flush(struct request_queue *q, struct gendisk *disk,
-                               sector_t *error_sector)
-{
-        ide_drive_t *drive = q->queuedata;
-        struct request *rq;
-        int ret;
-
-        if (!drive->wcache)
-                return 0;
-
-        rq = blk_get_request(q, WRITE, __GFP_WAIT);
-
-        idedisk_prepare_flush(q, rq);
-
-        ret = blk_execute_rq(q, disk, rq, 0);
-
-        /*
-         * if we failed and caller wants error offset, get it
-         */
-        if (ret && error_sector)
-                *error_sector = ide_get_error_location(drive, rq->cmd);
-
-        blk_put_request(rq);
-        return ret;
-}
-
 /*
  * This is tightly woven into the driver->do_special can not touch.
  * DON'T do it again until a total personality rewrite is committed.
@@ -781,7 +755,6 @@ static void update_ordered(ide_drive_t *drive)
         struct hd_driveid *id = drive->id;
         unsigned ordered = QUEUE_ORDERED_NONE;
         prepare_flush_fn *prep_fn = NULL;
-        issue_flush_fn *issue_fn = NULL;
 
         if (drive->wcache) {
                 unsigned long long capacity;
@@ -805,13 +778,11 @@ static void update_ordered(ide_drive_t *drive)
                 if (barrier) {
                         ordered = QUEUE_ORDERED_DRAIN_FLUSH;
                         prep_fn = idedisk_prepare_flush;
-                        issue_fn = idedisk_issue_flush;
                 }
         } else
                 ordered = QUEUE_ORDERED_DRAIN;
 
         blk_queue_ordered(drive->queue, ordered, prep_fn);
-        blk_queue_issue_flush_fn(drive->queue, issue_fn);
 }
 
 static int write_cache(ide_drive_t *drive, int arg)
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 2bcde5798b5a..fbe477bb2c68 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -999,33 +999,6 @@ void dm_table_unplug_all(struct dm_table *t)
         }
 }
 
-int dm_table_flush_all(struct dm_table *t)
-{
-        struct list_head *d, *devices = dm_table_get_devices(t);
-        int ret = 0;
-        unsigned i;
-
-        for (i = 0; i < t->num_targets; i++)
-                if (t->targets[i].type->flush)
-                        t->targets[i].type->flush(&t->targets[i]);
-
-        for (d = devices->next; d != devices; d = d->next) {
-                struct dm_dev *dd = list_entry(d, struct dm_dev, list);
-                struct request_queue *q = bdev_get_queue(dd->bdev);
-                int err;
-
-                if (!q->issue_flush_fn)
-                        err = -EOPNOTSUPP;
-                else
-                        err = q->issue_flush_fn(q, dd->bdev->bd_disk, NULL);
-
-                if (!ret)
-                        ret = err;
-        }
-
-        return ret;
-}
-
 struct mapped_device *dm_table_get_md(struct dm_table *t)
 {
         dm_get(t->md);
@@ -1043,4 +1016,3 @@ EXPORT_SYMBOL(dm_table_get_md);
 EXPORT_SYMBOL(dm_table_put);
 EXPORT_SYMBOL(dm_table_get);
 EXPORT_SYMBOL(dm_table_unplug_all);
-EXPORT_SYMBOL(dm_table_flush_all);
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 167765c47747..d837d37f6209 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -840,21 +840,6 @@ static int dm_request(struct request_queue *q, struct bio *bio)
         return 0;
 }
 
-static int dm_flush_all(struct request_queue *q, struct gendisk *disk,
-                        sector_t *error_sector)
-{
-        struct mapped_device *md = q->queuedata;
-        struct dm_table *map = dm_get_table(md);
-        int ret = -ENXIO;
-
-        if (map) {
-                ret = dm_table_flush_all(map);
-                dm_table_put(map);
-        }
-
-        return ret;
-}
-
 static void dm_unplug_all(struct request_queue *q)
 {
         struct mapped_device *md = q->queuedata;
@@ -1003,7 +988,6 @@ static struct mapped_device *alloc_dev(int minor)
         blk_queue_make_request(md->queue, dm_request);
         blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY);
         md->queue->unplug_fn = dm_unplug_all;
-        md->queue->issue_flush_fn = dm_flush_all;
 
         md->io_pool = mempool_create_slab_pool(MIN_IOS, _io_cache);
         if (!md->io_pool)
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index 462ee652a890..4b3faa45277e 100644
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -111,7 +111,6 @@ void dm_table_postsuspend_targets(struct dm_table *t);
 int dm_table_resume_targets(struct dm_table *t);
 int dm_table_any_congested(struct dm_table *t, int bdi_bits);
 void dm_table_unplug_all(struct dm_table *t);
-int dm_table_flush_all(struct dm_table *t);
 
 /*-----------------------------------------------------------------
  * A registry of target types.
diff --git a/drivers/md/linear.c b/drivers/md/linear.c
index 550148770bb2..56a11f6c127b 100644
--- a/drivers/md/linear.c
+++ b/drivers/md/linear.c
@@ -92,25 +92,6 @@ static void linear_unplug(struct request_queue *q)
         }
 }
 
-static int linear_issue_flush(struct request_queue *q, struct gendisk *disk,
-                              sector_t *error_sector)
-{
-        mddev_t *mddev = q->queuedata;
-        linear_conf_t *conf = mddev_to_conf(mddev);
-        int i, ret = 0;
-
-        for (i=0; i < mddev->raid_disks && ret == 0; i++) {
-                struct block_device *bdev = conf->disks[i].rdev->bdev;
-                struct request_queue *r_queue = bdev_get_queue(bdev);
-
-                if (!r_queue->issue_flush_fn)
-                        ret = -EOPNOTSUPP;
-                else
-                        ret = r_queue->issue_flush_fn(r_queue, bdev->bd_disk, error_sector);
-        }
-        return ret;
-}
-
 static int linear_congested(void *data, int bits)
 {
         mddev_t *mddev = data;
@@ -279,7 +260,6 @@ static int linear_run (mddev_t *mddev)
 
         blk_queue_merge_bvec(mddev->queue, linear_mergeable_bvec);
         mddev->queue->unplug_fn = linear_unplug;
-        mddev->queue->issue_flush_fn = linear_issue_flush;
         mddev->queue->backing_dev_info.congested_fn = linear_congested;
         mddev->queue->backing_dev_info.congested_data = mddev;
         return 0;
diff --git a/drivers/md/md.c b/drivers/md/md.c
index acf1b81b47cb..0dc563d76b39 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -3463,7 +3463,6 @@ static int do_md_stop(mddev_t * mddev, int mode)
                         mddev->pers->stop(mddev);
                         mddev->queue->merge_bvec_fn = NULL;
                         mddev->queue->unplug_fn = NULL;
-                        mddev->queue->issue_flush_fn = NULL;
                         mddev->queue->backing_dev_info.congested_fn = NULL;
                         if (mddev->pers->sync_request)
                                 sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index f2a63f394ad9..b35731cceac6 100644
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -194,35 +194,6 @@ static void multipath_status (struct seq_file *seq, mddev_t *mddev)
         seq_printf (seq, "]");
 }
 
-static int multipath_issue_flush(struct request_queue *q, struct gendisk *disk,
-                                 sector_t *error_sector)
-{
-        mddev_t *mddev = q->queuedata;
-        multipath_conf_t *conf = mddev_to_conf(mddev);
-        int i, ret = 0;
-
-        rcu_read_lock();
-        for (i=0; i<mddev->raid_disks && ret == 0; i++) {
-                mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev);
-                if (rdev && !test_bit(Faulty, &rdev->flags)) {
-                        struct block_device *bdev = rdev->bdev;
-                        struct request_queue *r_queue = bdev_get_queue(bdev);
-
-                        if (!r_queue->issue_flush_fn)
-                                ret = -EOPNOTSUPP;
-                        else {
-                                atomic_inc(&rdev->nr_pending);
-                                rcu_read_unlock();
-                                ret = r_queue->issue_flush_fn(r_queue, bdev->bd_disk,
-                                                              error_sector);
-                                rdev_dec_pending(rdev, mddev);
-                                rcu_read_lock();
-                        }
-                }
-        }
-        rcu_read_unlock();
-        return ret;
-}
 static int multipath_congested(void *data, int bits)
 {
         mddev_t *mddev = data;
@@ -527,7 +498,6 @@ static int multipath_run (mddev_t *mddev)
         mddev->array_size = mddev->size;
 
         mddev->queue->unplug_fn = multipath_unplug;
-        mddev->queue->issue_flush_fn = multipath_issue_flush;
         mddev->queue->backing_dev_info.congested_fn = multipath_congested;
         mddev->queue->backing_dev_info.congested_data = mddev;
 
diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
index ef0da2d84959..e79e1a538d44 100644
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -40,26 +40,6 @@ static void raid0_unplug(struct request_queue *q)
         }
 }
 
-static int raid0_issue_flush(struct request_queue *q, struct gendisk *disk,
-                             sector_t *error_sector)
-{
-        mddev_t *mddev = q->queuedata;
-        raid0_conf_t *conf = mddev_to_conf(mddev);
-        mdk_rdev_t **devlist = conf->strip_zone[0].dev;
-        int i, ret = 0;
-
-        for (i=0; i<mddev->raid_disks && ret == 0; i++) {
-                struct block_device *bdev = devlist[i]->bdev;
-                struct request_queue *r_queue = bdev_get_queue(bdev);
-
-                if (!r_queue->issue_flush_fn)
-                        ret = -EOPNOTSUPP;
-                else
-                        ret = r_queue->issue_flush_fn(r_queue, bdev->bd_disk, error_sector);
-        }
-        return ret;
-}
-
 static int raid0_congested(void *data, int bits)
 {
         mddev_t *mddev = data;
@@ -250,7 +230,6 @@ static int create_strip_zones (mddev_t *mddev)
 
         mddev->queue->unplug_fn = raid0_unplug;
 
-        mddev->queue->issue_flush_fn = raid0_issue_flush;
         mddev->queue->backing_dev_info.congested_fn = raid0_congested;
         mddev->queue->backing_dev_info.congested_data = mddev;
 
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 6d03bea6fa58..0bcefad82413 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -567,36 +567,6 @@ static void raid1_unplug(struct request_queue *q)
         md_wakeup_thread(mddev->thread);
 }
 
-static int raid1_issue_flush(struct request_queue *q, struct gendisk *disk,
-                             sector_t *error_sector)
-{
-        mddev_t *mddev = q->queuedata;
-        conf_t *conf = mddev_to_conf(mddev);
-        int i, ret = 0;
-
-        rcu_read_lock();
-        for (i=0; i<mddev->raid_disks && ret == 0; i++) {
-                mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
-                if (rdev && !test_bit(Faulty, &rdev->flags)) {
-                        struct block_device *bdev = rdev->bdev;
-                        struct request_queue *r_queue = bdev_get_queue(bdev);
-
-                        if (!r_queue->issue_flush_fn)
-                                ret = -EOPNOTSUPP;
-                        else {
-                                atomic_inc(&rdev->nr_pending);
-                                rcu_read_unlock();
-                                ret = r_queue->issue_flush_fn(r_queue, bdev->bd_disk,
-                                                              error_sector);
-                                rdev_dec_pending(rdev, mddev);
-                                rcu_read_lock();
-                        }
-                }
-        }
-        rcu_read_unlock();
-        return ret;
-}
-
 static int raid1_congested(void *data, int bits)
 {
         mddev_t *mddev = data;
@@ -1997,7 +1967,6 @@ static int run(mddev_t *mddev)
         mddev->array_size = mddev->size;
 
         mddev->queue->unplug_fn = raid1_unplug;
-        mddev->queue->issue_flush_fn = raid1_issue_flush;
         mddev->queue->backing_dev_info.congested_fn = raid1_congested;
         mddev->queue->backing_dev_info.congested_data = mddev;
 
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 25a96c42bdb0..fc6607acb6e4 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -611,36 +611,6 @@ static void raid10_unplug(struct request_queue *q)
         md_wakeup_thread(mddev->thread);
 }
 
-static int raid10_issue_flush(struct request_queue *q, struct gendisk *disk,
-                             sector_t *error_sector)
-{
-        mddev_t *mddev = q->queuedata;
-        conf_t *conf = mddev_to_conf(mddev);
-        int i, ret = 0;
-
-        rcu_read_lock();
-        for (i=0; i<mddev->raid_disks && ret == 0; i++) {
-                mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev);
-                if (rdev && !test_bit(Faulty, &rdev->flags)) {
-                        struct block_device *bdev = rdev->bdev;
-                        struct request_queue *r_queue = bdev_get_queue(bdev);
-
-                        if (!r_queue->issue_flush_fn)
-                                ret = -EOPNOTSUPP;
-                        else {
-                                atomic_inc(&rdev->nr_pending);
-                                rcu_read_unlock();
-                                ret = r_queue->issue_flush_fn(r_queue, bdev->bd_disk,
-                                                              error_sector);
-                                rdev_dec_pending(rdev, mddev);
-                                rcu_read_lock();
-                        }
-                }
-        }
-        rcu_read_unlock();
-        return ret;
-}
-
 static int raid10_congested(void *data, int bits)
 {
         mddev_t *mddev = data;
@@ -2118,7 +2088,6 @@ static int run(mddev_t *mddev)
         mddev->resync_max_sectors = size << conf->chunk_shift;
 
         mddev->queue->unplug_fn = raid10_unplug;
-        mddev->queue->issue_flush_fn = raid10_issue_flush;
         mddev->queue->backing_dev_info.congested_fn = raid10_congested;
         mddev->queue->backing_dev_info.congested_data = mddev;
 
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index caaca9e178bc..8ee181a01f52 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -3204,36 +3204,6 @@ static void raid5_unplug_device(struct request_queue *q)
         unplug_slaves(mddev);
 }
 
-static int raid5_issue_flush(struct request_queue *q, struct gendisk *disk,
-                             sector_t *error_sector)
-{
-        mddev_t *mddev = q->queuedata;
-        raid5_conf_t *conf = mddev_to_conf(mddev);
-        int i, ret = 0;
-
-        rcu_read_lock();
-        for (i=0; i<mddev->raid_disks && ret == 0; i++) {
-                mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev);
-                if (rdev && !test_bit(Faulty, &rdev->flags)) {
-                        struct block_device *bdev = rdev->bdev;
-                        struct request_queue *r_queue = bdev_get_queue(bdev);
-
-                        if (!r_queue->issue_flush_fn)
-                                ret = -EOPNOTSUPP;
-                        else {
-                                atomic_inc(&rdev->nr_pending);
-                                rcu_read_unlock();
-                                ret = r_queue->issue_flush_fn(r_queue, bdev->bd_disk,
-                                                              error_sector);
-                                rdev_dec_pending(rdev, mddev);
-                                rcu_read_lock();
-                        }
-                }
-        }
-        rcu_read_unlock();
-        return ret;
-}
-
 static int raid5_congested(void *data, int bits)
 {
         mddev_t *mddev = data;
@@ -4263,7 +4233,6 @@ static int run(mddev_t *mddev)
                        mdname(mddev));
 
         mddev->queue->unplug_fn = raid5_unplug_device;
-        mddev->queue->issue_flush_fn = raid5_issue_flush;
         mddev->queue->backing_dev_info.congested_data = mddev;
         mddev->queue->backing_dev_info.congested_fn = raid5_congested;
 
diff --git a/drivers/message/i2o/i2o_block.c b/drivers/message/i2o/i2o_block.c
index 50b2c7334410..d602ba6d5417 100644
--- a/drivers/message/i2o/i2o_block.c
+++ b/drivers/message/i2o/i2o_block.c
@@ -149,29 +149,6 @@ static int i2o_block_device_flush(struct i2o_device *dev)
 };
 
 /**
- *      i2o_block_issue_flush - device-flush interface for block-layer
- *      @queue: the request queue of the device which should be flushed
- *      @disk: gendisk
- *      @error_sector: error offset
- *
- *      Helper function to provide flush functionality to block-layer.
- *
- *      Returns 0 on success or negative error code on failure.
- */
-
-static int i2o_block_issue_flush(struct request_queue * queue, struct gendisk *disk,
-                                 sector_t * error_sector)
-{
-        struct i2o_block_device *i2o_blk_dev = queue->queuedata;
-        int rc = -ENODEV;
-
-        if (likely(i2o_blk_dev))
-                rc = i2o_block_device_flush(i2o_blk_dev->i2o_dev);
-
-        return rc;
-}
-
-/**
  *      i2o_block_device_mount - Mount (load) the media of device dev
  *      @dev: I2O device which should receive the mount request
  *      @media_id: Media Identifier
@@ -1009,7 +986,6 @@ static struct i2o_block_device *i2o_block_device_alloc(void)
         }
 
         blk_queue_prep_rq(queue, i2o_block_prep_req_fn);
-        blk_queue_issue_flush_fn(queue, i2o_block_issue_flush);
 
         gd->major = I2O_MAJOR;
         gd->queue = queue;
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 0a3a528212c2..69f542c4923c 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -826,27 +826,6 @@ static int sd_sync_cache(struct scsi_disk *sdkp)
         return 0;
 }
 
-static int sd_issue_flush(struct request_queue *q, struct gendisk *disk,
-                          sector_t *error_sector)
-{
-        int ret = 0;
-        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;
-
-        if (sdkp->WCE)
-                ret = sd_sync_cache(sdkp);
-        scsi_disk_put(sdkp);
-        return ret;
-}
-
 static void sd_prepare_flush(struct request_queue *q, struct request *rq)
 {
         memset(rq->cmd, 0, sizeof(rq->cmd));
@@ -1697,7 +1676,6 @@ 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;
         gd->flags = GENHD_FL_DRIVERFS;