[PATCH 16/27] bcache: super: use bio_get_base_vec

[Ming Lei]

Signed-off-by: Ming Lei <tom.leim...@gmail.com>
---
 drivers/md/bcache/super.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 3f649c9..56ad797 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -208,7 +208,12 @@ static void write_bdev_super_endio(struct bio *bio)
 
 static void __write_super(struct cache_sb *sb, struct bio *bio)
 {
-       struct cache_sb *out = page_address(bio->bi_io_vec[0].bv_page);
+       /*
+        * For accessing page pointed to by the 1st bvec, it
+        * works too after multipage bvecs.
+        */
+       struct bio_vec *bvec = bio_get_base_vec(bio);
+       struct cache_sb *out = page_address(bvec->bv_page);
        unsigned i;
 
        bio->bi_iter.bi_sector  = SB_SECTOR;
@@ -1145,6 +1150,7 @@ static void register_bdev(struct cache_sb *sb, struct 
page *sb_page,
        char name[BDEVNAME_SIZE];
        const char *err = "cannot allocate memory";
        struct cache_set *c;
+       struct bio_vec *bvec;
 
        memcpy(&dc->sb, sb, sizeof(struct cache_sb));
        dc->bdev = bdev;
@@ -1152,7 +1158,8 @@ static void register_bdev(struct cache_sb *sb, struct 
page *sb_page,
 
        bio_init(&dc->sb_bio);
        bio_set_vec_table(&dc->sb_bio, dc->sb_bio.bi_inline_vecs, 1);
-       dc->sb_bio.bi_io_vec[0].bv_page = sb_page;
+       bvec = bio_get_base_vec(&dc->sb_bio);
+       bvec->bv_page = sb_page;
        get_page(sb_page);
 
        if (cached_dev_init(dc, sb->block_size << 9))
@@ -1776,6 +1783,7 @@ void bch_cache_release(struct kobject *kobj)
 {
        struct cache *ca = container_of(kobj, struct cache, kobj);
        unsigned i;
+       struct bio_vec *bvec = bio_get_base_vec(&ca->sb_bio);
 
        if (ca->set) {
                BUG_ON(ca->set->cache[ca->sb.nr_this_dev] != ca);
@@ -1793,7 +1801,7 @@ void bch_cache_release(struct kobject *kobj)
                free_fifo(&ca->free[i]);
 
        if (ca->sb_bio.bi_inline_vecs[0].bv_page)
-               put_page(ca->sb_bio.bi_io_vec[0].bv_page);
+               put_page(bvec->bv_page);
 
        if (!IS_ERR_OR_NULL(ca->bdev))
                blkdev_put(ca->bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
@@ -1843,6 +1851,7 @@ static int register_cache(struct cache_sb *sb, struct 
page *sb_page,
        char name[BDEVNAME_SIZE];
        const char *err = NULL;
        int ret = 0;
+       struct bio_vec *bvec;
 
        memcpy(&ca->sb, sb, sizeof(struct cache_sb));
        ca->bdev = bdev;
@@ -1850,7 +1859,8 @@ static int register_cache(struct cache_sb *sb, struct 
page *sb_page,
 
        bio_init(&ca->sb_bio);
        bio_set_vec_table(&ca->sb_bio, ca->sb_bio.bi_inline_vecs, 1);
-       ca->sb_bio.bi_io_vec[0].bv_page = sb_page;
+       bvec = bio_get_base_vec(&ca->sb_bio);
+       bvec->bv_page = sb_page;
        get_page(sb_page);
 
        if (blk_queue_discard(bdev_get_queue(ca->bdev)))
-- 
1.9.1