Commit aa83da7f authored by Andreas Gruenbacher's avatar Andreas Gruenbacher

gfs2: More gfs2_find_jhead fixes

It turns out that when extending an existing bio, gfs2_find_jhead fails to
check if the block number is consecutive, which leads to incorrect reads for
fragmented journals.

In addition, limit the maximum bio size to an arbitrary value of 2 megabytes:
since commit 07173c3e ("block: enable multipage bvecs"), if we just keep
adding pages until bio_add_page fails, bios will grow much larger than useful,
which pins more memory than necessary with barely any additional performance
gains.

Fixes: f4686c26 ("gfs2: read journal in large chunks")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: default avatarAndreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: default avatarBob Peterson <rpeterso@redhat.com>
parent 566a2ab3
...@@ -263,7 +263,7 @@ static struct bio *gfs2_log_alloc_bio(struct gfs2_sbd *sdp, u64 blkno, ...@@ -263,7 +263,7 @@ static struct bio *gfs2_log_alloc_bio(struct gfs2_sbd *sdp, u64 blkno,
struct super_block *sb = sdp->sd_vfs; struct super_block *sb = sdp->sd_vfs;
struct bio *bio = bio_alloc(GFP_NOIO, BIO_MAX_PAGES); struct bio *bio = bio_alloc(GFP_NOIO, BIO_MAX_PAGES);
bio->bi_iter.bi_sector = blkno << (sb->s_blocksize_bits - 9); bio->bi_iter.bi_sector = blkno << sdp->sd_fsb2bb_shift;
bio_set_dev(bio, sb->s_bdev); bio_set_dev(bio, sb->s_bdev);
bio->bi_end_io = end_io; bio->bi_end_io = end_io;
bio->bi_private = sdp; bio->bi_private = sdp;
...@@ -509,7 +509,7 @@ int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head, ...@@ -509,7 +509,7 @@ int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head,
unsigned int bsize = sdp->sd_sb.sb_bsize, off; unsigned int bsize = sdp->sd_sb.sb_bsize, off;
unsigned int bsize_shift = sdp->sd_sb.sb_bsize_shift; unsigned int bsize_shift = sdp->sd_sb.sb_bsize_shift;
unsigned int shift = PAGE_SHIFT - bsize_shift; unsigned int shift = PAGE_SHIFT - bsize_shift;
unsigned int readahead_blocks = BIO_MAX_PAGES << shift; unsigned int max_bio_size = 2 * 1024 * 1024;
struct gfs2_journal_extent *je; struct gfs2_journal_extent *je;
int sz, ret = 0; int sz, ret = 0;
struct bio *bio = NULL; struct bio *bio = NULL;
...@@ -537,12 +537,17 @@ int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head, ...@@ -537,12 +537,17 @@ int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head,
off = 0; off = 0;
} }
if (!bio || (bio_chained && !off)) { if (!bio || (bio_chained && !off) ||
bio->bi_iter.bi_size >= max_bio_size) {
/* start new bio */ /* start new bio */
} else { } else {
sz = bio_add_page(bio, page, bsize, off); sector_t sector = dblock << sdp->sd_fsb2bb_shift;
if (sz == bsize)
goto block_added; if (bio_end_sector(bio) == sector) {
sz = bio_add_page(bio, page, bsize, off);
if (sz == bsize)
goto block_added;
}
if (off) { if (off) {
unsigned int blocks = unsigned int blocks =
(PAGE_SIZE - off) >> bsize_shift; (PAGE_SIZE - off) >> bsize_shift;
...@@ -568,7 +573,7 @@ int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head, ...@@ -568,7 +573,7 @@ int gfs2_find_jhead(struct gfs2_jdesc *jd, struct gfs2_log_header_host *head,
off += bsize; off += bsize;
if (off == PAGE_SIZE) if (off == PAGE_SIZE)
page = NULL; page = NULL;
if (blocks_submitted < blocks_read + readahead_blocks) { if (blocks_submitted < 2 * max_bio_size >> bsize_shift) {
/* Keep at least one bio in flight */ /* Keep at least one bio in flight */
continue; continue;
} }
......
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