gfs2: Fix extended attribute readahead optimization
Commit 39b0555f didn't check for a failing bio_add_page in
gfs2_submit_bhs. This could cause I/O requests to get lost, and the
affected buffer heads to stay locked forever. Fix that by submitting
the current bio and allocating another one when bio_add_page fails. (It
is guaranteed that we can at least add one page to a bio.)
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c
index 950b8be..373639a5 100644
--- a/fs/gfs2/meta_io.c
+++ b/fs/gfs2/meta_io.c
@@ -216,23 +216,26 @@
static void gfs2_submit_bhs(int op, int op_flags, struct buffer_head *bhs[],
int num)
{
- struct buffer_head *bh = bhs[0];
- struct bio *bio;
- int i;
+ while (num > 0) {
+ struct buffer_head *bh = *bhs;
+ struct bio *bio;
- if (!num)
- return;
-
- bio = bio_alloc(GFP_NOIO, num);
- bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
- bio->bi_bdev = bh->b_bdev;
- for (i = 0; i < num; i++) {
- bh = bhs[i];
- bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh));
+ bio = bio_alloc(GFP_NOIO, num);
+ bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
+ bio->bi_bdev = bh->b_bdev;
+ while (num > 0) {
+ bh = *bhs;
+ if (!bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh))) {
+ BUG_ON(bio->bi_iter.bi_size == 0);
+ break;
+ }
+ bhs++;
+ num--;
+ }
+ bio->bi_end_io = gfs2_meta_read_endio;
+ bio_set_op_attrs(bio, op, op_flags);
+ submit_bio(bio);
}
- bio->bi_end_io = gfs2_meta_read_endio;
- bio_set_op_attrs(bio, op, op_flags);
- submit_bio(bio);
}
/**
