block: remove the BLKDEV_IFL_BARRIER flag

Remove support for barriers on discards, which is unused now.  Also
remove the DISCARD_NOBARRIER I/O type in favour of just setting the
rw flags up locally in blkdev_issue_discard.

tj: Also remove DISCARD_SECURE and use REQ_SECURE directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

3 files changed, 2 insertions, 26 deletions

diff --git a/block/blk-lib.c b/block/blk-lib.c
index c392029a104e..fe2e6ed0f510 100644
--- a/block/blk-lib.c
+++ b/block/blk-lib.c
@@ -39,8 +39,7 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
 {
         DECLARE_COMPLETION_ONSTACK(wait);
         struct request_queue *q = bdev_get_queue(bdev);
-        int type = flags & BLKDEV_IFL_BARRIER ?
-                DISCARD_BARRIER : DISCARD_NOBARRIER;
+        int type = REQ_WRITE | REQ_DISCARD;
         unsigned int max_discard_sectors;
         struct bio *bio;
         int ret = 0;
@@ -65,7 +64,7 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
         if (flags & BLKDEV_IFL_SECURE) {
                 if (!blk_queue_secdiscard(q))
                         return -EOPNOTSUPP;
-                type |= DISCARD_SECURE;
+                type |= REQ_SECURE;
         }
 
         while (nr_sects && !ret) {
@@ -162,12 +161,6 @@ int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
         bb.wait = &wait;
         bb.end_io = NULL;
 
-        if (flags & BLKDEV_IFL_BARRIER) {
-                /* issue async barrier before the data */
-                ret = blkdev_issue_flush(bdev, gfp_mask, NULL, 0);
-                if (ret)
-                        return ret;
-        }
 submit:
         ret = 0;
         while (nr_sects != 0) {
@@ -199,13 +192,6 @@ submit:
                 issued++;
                 submit_bio(WRITE, bio);
         }
-        /*
-         * When all data bios are in flight. Send final barrier if requeted.
-         */
-        if (nr_sects == 0 && flags & BLKDEV_IFL_BARRIER)
-                ret = blkdev_issue_flush(bdev, gfp_mask, NULL,
-                                        flags & BLKDEV_IFL_WAIT);
-
 
         if (flags & BLKDEV_IFL_WAIT)
                 /* Wait for bios in-flight */
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 6b305eb4a343..cfcb3a610605 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -869,11 +869,9 @@ static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
 }
 enum{
         BLKDEV_WAIT,    /* wait for completion */
-        BLKDEV_BARRIER, /* issue request with barrier */
         BLKDEV_SECURE,  /* secure discard */
 };
 #define BLKDEV_IFL_WAIT         (1 << BLKDEV_WAIT)
-#define BLKDEV_IFL_BARRIER      (1 << BLKDEV_BARRIER)
 #define BLKDEV_IFL_SECURE       (1 << BLKDEV_SECURE)
 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *,
                         unsigned long);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index d6add69bc170..6b0f6e9993a3 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -163,14 +163,6 @@ struct inodes_stat_t {
 #define WRITE_FLUSH_FUA         (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG | \
                                  REQ_FLUSH | REQ_FUA)
 
-/*
- * These aren't really reads or writes, they pass down information about
- * parts of device that are now unused by the file system.
- */
-#define DISCARD_NOBARRIER       (WRITE | REQ_DISCARD)
-#define DISCARD_BARRIER         (WRITE | REQ_DISCARD | REQ_HARDBARRIER)
-#define DISCARD_SECURE          (DISCARD_NOBARRIER | REQ_SECURE)
-
 #define SEL_IN          1
 #define SEL_OUT         2
 #define SEL_EX          4