block: remove struct bio_batch

It can be replaced with a combination of bio_chain and submit_bio_wait.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Signed-off-by: Sagi Grimberg <sagig@grimberg.me>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/block/blk-lib.c b/block/blk-lib.c
index 9ebf65379556a0f5730b3934acd2fa78e232e816..700d248cbde506392fc4dbc8931789ebd4df6608 100644 (file)
--- a/block/blk-lib.c
+++ b/block/blk-lib.c
@@ -9,21 +9,17 @@
 
 #include "blk.h"
 
-struct bio_batch {
-       atomic_t                done;
-       int                     error;
-       struct completion       *wait;
-};
-
-static void bio_batch_end_io(struct bio *bio)
+static struct bio *next_bio(struct bio *bio, int rw, unsigned int nr_pages,
+               gfp_t gfp)
 {
-       struct bio_batch *bb = bio->bi_private;
+       struct bio *new = bio_alloc(gfp, nr_pages);
+
+       if (bio) {
+               bio_chain(bio, new);
+               submit_bio(rw, bio);
+       }
 
-       if (bio->bi_error && bio->bi_error != -EOPNOTSUPP)
-               bb->error = bio->bi_error;
-       if (atomic_dec_and_test(&bb->done))
-               complete(bb->wait);
-       bio_put(bio);
+       return new;
 }
 
 /**
@@ -40,13 +36,11 @@ static void bio_batch_end_io(struct bio *bio)
 int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
                sector_t nr_sects, gfp_t gfp_mask, unsigned long flags)
 {
-       DECLARE_COMPLETION_ONSTACK(wait);
        struct request_queue *q = bdev_get_queue(bdev);
        int type = REQ_WRITE | REQ_DISCARD;
        unsigned int granularity;
        int alignment;
-       struct bio_batch bb;
-       struct bio *bio;
+       struct bio *bio = NULL;
        int ret = 0;
        struct blk_plug plug;
 
@@ -66,25 +60,15 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
                type |= REQ_SECURE;
        }
 
-       atomic_set(&bb.done, 1);
-       bb.error = 0;
-       bb.wait = &wait;
-
        blk_start_plug(&plug);
        while (nr_sects) {
                unsigned int req_sects;
                sector_t end_sect, tmp;
 
-               bio = bio_alloc(gfp_mask, 1);
-               if (!bio) {
-                       ret = -ENOMEM;
-                       break;
-               }
-
                /* Make sure bi_size doesn't overflow */
                req_sects = min_t(sector_t, nr_sects, UINT_MAX >> 9);
 
-               /*
+               /**
                 * If splitting a request, and the next starting sector would be
                 * misaligned, stop the discard at the previous aligned sector.
                 */
@@ -98,18 +82,14 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
                        req_sects = end_sect - sector;
                }
 
+               bio = next_bio(bio, type, 1, gfp_mask);
                bio->bi_iter.bi_sector = sector;
-               bio->bi_end_io = bio_batch_end_io;
                bio->bi_bdev = bdev;
-               bio->bi_private = &bb;
 
                bio->bi_iter.bi_size = req_sects << 9;
                nr_sects -= req_sects;
                sector = end_sect;
 
-               atomic_inc(&bb.done);
-               submit_bio(type, bio);
-
                /*
                 * We can loop for a long time in here, if someone does
                 * full device discards (like mkfs). Be nice and allow
@@ -118,15 +98,11 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
                 */
                cond_resched();
        }
+       if (bio)
+               ret = submit_bio_wait(type, bio);
        blk_finish_plug(&plug);
 
-       /* Wait for bios in-flight */
-       if (!atomic_dec_and_test(&bb.done))
-               wait_for_completion_io(&wait);
-
-       if (bb.error)
-               return bb.error;
-       return ret;
+       return ret != -EOPNOTSUPP ? ret : 0;
 }
 EXPORT_SYMBOL(blkdev_issue_discard);
 
@@ -145,11 +121,9 @@ int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
                            sector_t nr_sects, gfp_t gfp_mask,
                            struct page *page)
 {
-       DECLARE_COMPLETION_ONSTACK(wait);
        struct request_queue *q = bdev_get_queue(bdev);
        unsigned int max_write_same_sectors;
-       struct bio_batch bb;
-       struct bio *bio;
+       struct bio *bio = NULL;
        int ret = 0;
 
        if (!q)
@@ -158,21 +132,10 @@ int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
        /* Ensure that max_write_same_sectors doesn't overflow bi_size */
        max_write_same_sectors = UINT_MAX >> 9;
 
-       atomic_set(&bb.done, 1);
-       bb.error = 0;
-       bb.wait = &wait;
-
        while (nr_sects) {
-               bio = bio_alloc(gfp_mask, 1);
-               if (!bio) {
-                       ret = -ENOMEM;
-                       break;
-               }
-
+               bio = next_bio(bio, REQ_WRITE | REQ_WRITE_SAME, 1, gfp_mask);
                bio->bi_iter.bi_sector = sector;
-               bio->bi_end_io = bio_batch_end_io;
                bio->bi_bdev = bdev;
-               bio->bi_private = &bb;
                bio->bi_vcnt = 1;
                bio->bi_io_vec->bv_page = page;
                bio->bi_io_vec->bv_offset = 0;
@@ -186,18 +149,11 @@ int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
                        bio->bi_iter.bi_size = nr_sects << 9;
                        nr_sects = 0;
                }
-
-               atomic_inc(&bb.done);
-               submit_bio(REQ_WRITE | REQ_WRITE_SAME, bio);
        }
 
-       /* Wait for bios in-flight */
-       if (!atomic_dec_and_test(&bb.done))
-               wait_for_completion_io(&wait);
-
-       if (bb.error)
-               return bb.error;
-       return ret;
+       if (bio)
+               ret = submit_bio_wait(REQ_WRITE | REQ_WRITE_SAME, bio);
+       return ret != -EOPNOTSUPP ? ret : 0;
 }
 EXPORT_SYMBOL(blkdev_issue_write_same);
 
@@ -216,28 +172,15 @@ static int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
                                  sector_t nr_sects, gfp_t gfp_mask)
 {
        int ret;
-       struct bio *bio;
-       struct bio_batch bb;
+       struct bio *bio = NULL;
        unsigned int sz;
-       DECLARE_COMPLETION_ONSTACK(wait);
 
-       atomic_set(&bb.done, 1);
-       bb.error = 0;
-       bb.wait = &wait;
-
-       ret = 0;
        while (nr_sects != 0) {
-               bio = bio_alloc(gfp_mask,
-                               min(nr_sects, (sector_t)BIO_MAX_PAGES));
-               if (!bio) {
-                       ret = -ENOMEM;
-                       break;
-               }
-
+               bio = next_bio(bio, WRITE,
+                               min(nr_sects, (sector_t)BIO_MAX_PAGES),
+                               gfp_mask);
                bio->bi_iter.bi_sector = sector;
                bio->bi_bdev   = bdev;
-               bio->bi_end_io = bio_batch_end_io;
-               bio->bi_private = &bb;
 
                while (nr_sects != 0) {
                        sz = min((sector_t) PAGE_SIZE >> 9 , nr_sects);
@@ -247,18 +190,11 @@ static int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
                        if (ret < (sz << 9))
                                break;
                }
-               ret = 0;
-               atomic_inc(&bb.done);
-               submit_bio(WRITE, bio);
        }
 
-       /* Wait for bios in-flight */
-       if (!atomic_dec_and_test(&bb.done))
-               wait_for_completion_io(&wait);
-
-       if (bb.error)
-               return bb.error;
-       return ret;
+       if (bio)
+               return submit_bio_wait(WRITE, bio);
+       return 0;
 }
 
 /**