block: Convert various code to bio_for_each_segment()
With immutable biovecs we don't want code accessing bi_io_vec directly -
the uses this patch changes weren't incorrect since they all own the
bio, but it makes the code harder to audit for no good reason - also,
this will help with multipage bvecs later.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Cc: Joern Engel <joern@logfs.org>
Cc: Prasad Joshi <prasadjoshi.linux@gmail.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index ff43802..8b5f9e1 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2332,12 +2332,13 @@
*/
static void end_bio_extent_writepage(struct bio *bio, int err)
{
- struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
+ struct bio_vec *bvec;
struct extent_io_tree *tree;
u64 start;
u64 end;
+ int i;
- do {
+ bio_for_each_segment_all(bvec, bio, i) {
struct page *page = bvec->bv_page;
tree = &BTRFS_I(page->mapping->host)->io_tree;
@@ -2355,14 +2356,11 @@
start = page_offset(page);
end = start + bvec->bv_offset + bvec->bv_len - 1;
- if (--bvec >= bio->bi_io_vec)
- prefetchw(&bvec->bv_page->flags);
-
if (end_extent_writepage(page, err, start, end))
continue;
end_page_writeback(page);
- } while (bvec >= bio->bi_io_vec);
+ }
bio_put(bio);
}
@@ -2392,9 +2390,8 @@
*/
static void end_bio_extent_readpage(struct bio *bio, int err)
{
+ struct bio_vec *bvec;
int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
- struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1;
- struct bio_vec *bvec = bio->bi_io_vec;
struct btrfs_io_bio *io_bio = btrfs_io_bio(bio);
struct extent_io_tree *tree;
u64 offset = 0;
@@ -2405,11 +2402,12 @@
u64 extent_len = 0;
int mirror;
int ret;
+ int i;
if (err)
uptodate = 0;
- do {
+ bio_for_each_segment_all(bvec, bio, i) {
struct page *page = bvec->bv_page;
struct inode *inode = page->mapping->host;
@@ -2433,9 +2431,6 @@
end = start + bvec->bv_offset + bvec->bv_len - 1;
len = bvec->bv_len;
- if (++bvec <= bvec_end)
- prefetchw(&bvec->bv_page->flags);
-
mirror = io_bio->mirror_num;
if (likely(uptodate && tree->ops &&
tree->ops->readpage_end_io_hook)) {
@@ -2516,7 +2511,7 @@
extent_start = start;
extent_len = end + 1 - start;
}
- } while (bvec <= bvec_end);
+ }
if (extent_len)
endio_readpage_release_extent(tree, extent_start, extent_len,
@@ -2547,7 +2542,6 @@
}
if (bio) {
- bio->bi_size = 0;
bio->bi_bdev = bdev;
bio->bi_sector = first_sector;
btrfs_bio = btrfs_io_bio(bio);
@@ -3410,20 +3404,18 @@
static void end_bio_extent_buffer_writepage(struct bio *bio, int err)
{
- int uptodate = err == 0;
- struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
+ struct bio_vec *bvec;
struct extent_buffer *eb;
- int done;
+ int i, done;
- do {
+ bio_for_each_segment_all(bvec, bio, i) {
struct page *page = bvec->bv_page;
- bvec--;
eb = (struct extent_buffer *)page->private;
BUG_ON(!eb);
done = atomic_dec_and_test(&eb->io_pages);
- if (!uptodate || test_bit(EXTENT_BUFFER_IOERR, &eb->bflags)) {
+ if (err || test_bit(EXTENT_BUFFER_IOERR, &eb->bflags)) {
set_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
ClearPageUptodate(page);
SetPageError(page);
@@ -3435,10 +3427,9 @@
continue;
end_extent_buffer_writeback(eb);
- } while (bvec >= bio->bi_io_vec);
+ }
bio_put(bio);
-
}
static int write_one_eb(struct extent_buffer *eb,