[PATCH AUTOSEL 5.5 27/41] dm integrity: use dm_bio_record and dm_bio_restore

From: Sasha Levin
Date: Sun Mar 15 2020 - 22:40:53 EST


From: Mike Snitzer <snitzer@xxxxxxxxxx>

[ Upstream commit 248aa2645aa7fc9175d1107c2593cc90d4af5a4e ]

In cases where dec_in_flight() has to requeue the integrity_bio_wait
work to transfer the rest of the data, the bio's __bi_remaining might
already have been decremented to 0, e.g.: if bio passed to underlying
data device was split via blk_queue_split().

Use dm_bio_{record,restore} rather than effectively open-coding them in
dm-integrity -- these methods now manage __bi_remaining too.

Depends-on: f7f0b057a9c1 ("dm bio record: save/restore bi_end_io and bi_integrity")
Reported-by: Daniel GlÃckner <dg@xxxxxxxxx>
Suggested-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/md/dm-integrity.c | 32 +++++++++-----------------------
1 file changed, 9 insertions(+), 23 deletions(-)

diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c
index e1ad0b53f681a..a82a9c2577443 100644
--- a/drivers/md/dm-integrity.c
+++ b/drivers/md/dm-integrity.c
@@ -6,6 +6,8 @@
* This file is released under the GPL.
*/

+#include "dm-bio-record.h"
+
#include <linux/compiler.h>
#include <linux/module.h>
#include <linux/device-mapper.h>
@@ -295,11 +297,7 @@ struct dm_integrity_io {

struct completion *completion;

- struct gendisk *orig_bi_disk;
- u8 orig_bi_partno;
- bio_end_io_t *orig_bi_end_io;
- struct bio_integrity_payload *orig_bi_integrity;
- struct bvec_iter orig_bi_iter;
+ struct dm_bio_details bio_details;
};

struct journal_completion {
@@ -1452,14 +1450,9 @@ static void integrity_end_io(struct bio *bio)
{
struct dm_integrity_io *dio = dm_per_bio_data(bio, sizeof(struct dm_integrity_io));

- bio->bi_iter = dio->orig_bi_iter;
- bio->bi_disk = dio->orig_bi_disk;
- bio->bi_partno = dio->orig_bi_partno;
- if (dio->orig_bi_integrity) {
- bio->bi_integrity = dio->orig_bi_integrity;
+ dm_bio_restore(&dio->bio_details, bio);
+ if (bio->bi_integrity)
bio->bi_opf |= REQ_INTEGRITY;
- }
- bio->bi_end_io = dio->orig_bi_end_io;

if (dio->completion)
complete(dio->completion);
@@ -1544,7 +1537,7 @@ static void integrity_metadata(struct work_struct *w)
}
}

- __bio_for_each_segment(bv, bio, iter, dio->orig_bi_iter) {
+ __bio_for_each_segment(bv, bio, iter, dio->bio_details.bi_iter) {
unsigned pos;
char *mem, *checksums_ptr;

@@ -1588,7 +1581,7 @@ static void integrity_metadata(struct work_struct *w)
if (likely(checksums != checksums_onstack))
kfree(checksums);
} else {
- struct bio_integrity_payload *bip = dio->orig_bi_integrity;
+ struct bio_integrity_payload *bip = dio->bio_details.bi_integrity;

if (bip) {
struct bio_vec biv;
@@ -2007,20 +2000,13 @@ static void dm_integrity_map_continue(struct dm_integrity_io *dio, bool from_map
} else
dio->completion = NULL;

- dio->orig_bi_iter = bio->bi_iter;
-
- dio->orig_bi_disk = bio->bi_disk;
- dio->orig_bi_partno = bio->bi_partno;
+ dm_bio_record(&dio->bio_details, bio);
bio_set_dev(bio, ic->dev->bdev);
-
- dio->orig_bi_integrity = bio_integrity(bio);
bio->bi_integrity = NULL;
bio->bi_opf &= ~REQ_INTEGRITY;
-
- dio->orig_bi_end_io = bio->bi_end_io;
bio->bi_end_io = integrity_end_io;
-
bio->bi_iter.bi_size = dio->range.n_sectors << SECTOR_SHIFT;
+
generic_make_request(bio);

if (need_sync_io) {
--
2.20.1