Btrfs: Direct I/O read: Work on sectorsized blocks
The direct I/O read's endio and corresponding repair functions work on
page sized blocks. This commit adds the ability for direct I/O read to work on
subpagesized blocks.
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index e456545..53c9dd1 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -7751,9 +7751,9 @@
}
static int dio_read_error(struct inode *inode, struct bio *failed_bio,
- struct page *page, u64 start, u64 end,
- int failed_mirror, bio_end_io_t *repair_endio,
- void *repair_arg)
+ struct page *page, unsigned int pgoff,
+ u64 start, u64 end, int failed_mirror,
+ bio_end_io_t *repair_endio, void *repair_arg)
{
struct io_failure_record *failrec;
struct bio *bio;
@@ -7774,7 +7774,9 @@
return -EIO;
}
- if (failed_bio->bi_vcnt > 1)
+ if ((failed_bio->bi_vcnt > 1)
+ || (failed_bio->bi_io_vec->bv_len
+ > BTRFS_I(inode)->root->sectorsize))
read_mode = READ_SYNC | REQ_FAILFAST_DEV;
else
read_mode = READ_SYNC;
@@ -7782,7 +7784,7 @@
isector = start - btrfs_io_bio(failed_bio)->logical;
isector >>= inode->i_sb->s_blocksize_bits;
bio = btrfs_create_repair_bio(inode, failed_bio, failrec, page,
- 0, isector, repair_endio, repair_arg);
+ pgoff, isector, repair_endio, repair_arg);
if (!bio) {
free_io_failure(inode, failrec);
return -EIO;
@@ -7812,12 +7814,17 @@
static void btrfs_retry_endio_nocsum(struct bio *bio)
{
struct btrfs_retry_complete *done = bio->bi_private;
+ struct inode *inode;
struct bio_vec *bvec;
int i;
if (bio->bi_error)
goto end;
+ ASSERT(bio->bi_vcnt == 1);
+ inode = bio->bi_io_vec->bv_page->mapping->host;
+ ASSERT(bio->bi_io_vec->bv_len == BTRFS_I(inode)->root->sectorsize);
+
done->uptodate = 1;
bio_for_each_segment_all(bvec, bio, i)
clean_io_failure(done->inode, done->start, bvec->bv_page, 0);
@@ -7829,25 +7836,35 @@
static int __btrfs_correct_data_nocsum(struct inode *inode,
struct btrfs_io_bio *io_bio)
{
+ struct btrfs_fs_info *fs_info;
struct bio_vec *bvec;
struct btrfs_retry_complete done;
u64 start;
+ unsigned int pgoff;
+ u32 sectorsize;
+ int nr_sectors;
int i;
int ret;
+ fs_info = BTRFS_I(inode)->root->fs_info;
+ sectorsize = BTRFS_I(inode)->root->sectorsize;
+
start = io_bio->logical;
done.inode = inode;
bio_for_each_segment_all(bvec, &io_bio->bio, i) {
-try_again:
+ nr_sectors = BTRFS_BYTES_TO_BLKS(fs_info, bvec->bv_len);
+ pgoff = bvec->bv_offset;
+
+next_block_or_try_again:
done.uptodate = 0;
done.start = start;
init_completion(&done.done);
- ret = dio_read_error(inode, &io_bio->bio, bvec->bv_page, start,
- start + bvec->bv_len - 1,
- io_bio->mirror_num,
- btrfs_retry_endio_nocsum, &done);
+ ret = dio_read_error(inode, &io_bio->bio, bvec->bv_page,
+ pgoff, start, start + sectorsize - 1,
+ io_bio->mirror_num,
+ btrfs_retry_endio_nocsum, &done);
if (ret)
return ret;
@@ -7855,10 +7872,15 @@
if (!done.uptodate) {
/* We might have another mirror, so try again */
- goto try_again;
+ goto next_block_or_try_again;
}
- start += bvec->bv_len;
+ start += sectorsize;
+
+ if (nr_sectors--) {
+ pgoff += sectorsize;
+ goto next_block_or_try_again;
+ }
}
return 0;
@@ -7868,7 +7890,9 @@
{
struct btrfs_retry_complete *done = bio->bi_private;
struct btrfs_io_bio *io_bio = btrfs_io_bio(bio);
+ struct inode *inode;
struct bio_vec *bvec;
+ u64 start;
int uptodate;
int ret;
int i;
@@ -7877,13 +7901,20 @@
goto end;
uptodate = 1;
+
+ start = done->start;
+
+ ASSERT(bio->bi_vcnt == 1);
+ inode = bio->bi_io_vec->bv_page->mapping->host;
+ ASSERT(bio->bi_io_vec->bv_len == BTRFS_I(inode)->root->sectorsize);
+
bio_for_each_segment_all(bvec, bio, i) {
ret = __readpage_endio_check(done->inode, io_bio, i,
- bvec->bv_page, 0,
- done->start, bvec->bv_len);
+ bvec->bv_page, bvec->bv_offset,
+ done->start, bvec->bv_len);
if (!ret)
clean_io_failure(done->inode, done->start,
- bvec->bv_page, 0);
+ bvec->bv_page, bvec->bv_offset);
else
uptodate = 0;
}
@@ -7897,20 +7928,34 @@
static int __btrfs_subio_endio_read(struct inode *inode,
struct btrfs_io_bio *io_bio, int err)
{
+ struct btrfs_fs_info *fs_info;
struct bio_vec *bvec;
struct btrfs_retry_complete done;
u64 start;
u64 offset = 0;
+ u32 sectorsize;
+ int nr_sectors;
+ unsigned int pgoff;
+ int csum_pos;
int i;
int ret;
+ fs_info = BTRFS_I(inode)->root->fs_info;
+ sectorsize = BTRFS_I(inode)->root->sectorsize;
+
err = 0;
start = io_bio->logical;
done.inode = inode;
bio_for_each_segment_all(bvec, &io_bio->bio, i) {
- ret = __readpage_endio_check(inode, io_bio, i, bvec->bv_page,
- 0, start, bvec->bv_len);
+ nr_sectors = BTRFS_BYTES_TO_BLKS(fs_info, bvec->bv_len);
+
+ pgoff = bvec->bv_offset;
+next_block:
+ csum_pos = BTRFS_BYTES_TO_BLKS(fs_info, offset);
+ ret = __readpage_endio_check(inode, io_bio, csum_pos,
+ bvec->bv_page, pgoff, start,
+ sectorsize);
if (likely(!ret))
goto next;
try_again:
@@ -7918,10 +7963,10 @@
done.start = start;
init_completion(&done.done);
- ret = dio_read_error(inode, &io_bio->bio, bvec->bv_page, start,
- start + bvec->bv_len - 1,
- io_bio->mirror_num,
- btrfs_retry_endio, &done);
+ ret = dio_read_error(inode, &io_bio->bio, bvec->bv_page,
+ pgoff, start, start + sectorsize - 1,
+ io_bio->mirror_num,
+ btrfs_retry_endio, &done);
if (ret) {
err = ret;
goto next;
@@ -7934,8 +7979,15 @@
goto try_again;
}
next:
- offset += bvec->bv_len;
- start += bvec->bv_len;
+ offset += sectorsize;
+ start += sectorsize;
+
+ ASSERT(nr_sectors);
+
+ if (--nr_sectors) {
+ pgoff += sectorsize;
+ goto next_block;
+ }
}
return err;