[PATCH v1 16/27] bcache: super: use bio_get_base_vec

Ming Lei
2016-04-14T12:03:40Z

drivers/md/bcache/super.c | 23 +++++++++++++++++++----
1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 3fa1ecf..d7fda32 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 +1158,9 @@ 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;
+ /* single bvec, still works after multipage bvecs */
+ 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 +1784,11 @@ void bch_cache_release(struct kobject *kobj)
{
struct cache *ca = container_of(kobj, struct cache, kobj);
unsigned i;
+ /*
+ * For accessing page pointed to by the 1st bvec, it
+ * works too after multipage bvecs.
+ */
+ 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 +1806,7 @@ 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 +1856,7 @@ 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 +1864,8 @@ 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