For commands like REQ_COPY we need a way to pass extra information along
with each bio. Like integrity metadata this information must be
available at the bottom of the stack so bi_private does not suffice.
Rename the existing bi_integrity field to bi_special and make it a union
so we can have different bio extensions for each class of command.
We previously used bi_integrity != NULL as a way to identify whether a
bio had integrity metadata or not. Introduce a REQ_INTEGRITY to be the
indicator now that bi_special can contain different things.
In addition, bio_integrity(bio) will now return a pointer to the
integrity payload (when applicable).
Signed-off-by: Martin K. Petersen <martin.peter...@oracle.com>
---
Documentation/block/data-integrity.txt | 10 +++++-----
block/bio-integrity.c | 19 ++++++++++---------
drivers/scsi/sd_dif.c | 8 ++++----
include/linux/bio.h | 11 +++++++++--
include/linux/blk_types.h | 8 ++++++--
include/linux/blkdev.h | 7 ++-----
6 files changed, 36 insertions(+), 27 deletions(-)
diff --git a/Documentation/block/data-integrity.txt
b/Documentation/block/data-integrity.txt
index b4eacf48053c..4d4de8b09530 100644
--- a/Documentation/block/data-integrity.txt
+++ b/Documentation/block/data-integrity.txt
@@ -129,11 +129,11 @@ interface for this is being worked on.
4.1 BIO
The data integrity patches add a new field to struct bio when
-CONFIG_BLK_DEV_INTEGRITY is enabled. bio->bi_integrity is a pointer
-to a struct bip which contains the bio integrity payload. Essentially
-a bip is a trimmed down struct bio which holds a bio_vec containing
-the integrity metadata and the required housekeeping information (bvec
-pool, vector count, etc.)
+CONFIG_BLK_DEV_INTEGRITY is enabled. bio_integrity(bio) returns a
+pointer to a struct bip which contains the bio integrity payload.
+Essentially a bip is a trimmed down struct bio which holds a bio_vec
+containing the integrity metadata and the required housekeeping
+information (bvec pool, vector count, etc.)
A kernel subsystem can enable data integrity protection on a bio by
calling bio_integrity_alloc(bio). This will allocate and attach the
diff --git a/block/bio-integrity.c b/block/bio-integrity.c
index 6818c251e937..78d8312a6528 100644
--- a/block/bio-integrity.c
+++ b/block/bio-integrity.c
@@ -77,6 +77,7 @@ struct bio_integrity_payload *bio_integrity_alloc(struct bio
*bio,
bip->bip_slab = idx;
bip->bip_bio = bio;
bio->bi_integrity = bip;
+ bio->bi_rw |= REQ_INTEGRITY;
return bip;
err:
@@ -94,7 +95,7 @@ EXPORT_SYMBOL(bio_integrity_alloc);
*/
void bio_integrity_free(struct bio *bio)
{
- struct bio_integrity_payload *bip = bio->bi_integrity;
+ struct bio_integrity_payload *bip = bio_integrity(bio);
struct bio_set *bs = bio->bi_pool;
if (bip->bip_owns_buf)
@@ -134,7 +135,7 @@ static inline unsigned int bip_integrity_vecs(struct
bio_integrity_payload *bip)
int bio_integrity_add_page(struct bio *bio, struct page *page,
unsigned int len, unsigned int offset)
{
- struct bio_integrity_payload *bip = bio->bi_integrity;
+ struct bio_integrity_payload *bip = bio_integrity(bio);
struct bio_vec *iv;
if (bip->bip_vcnt >= bip_integrity_vecs(bip)) {
@@ -235,7 +236,7 @@ EXPORT_SYMBOL(bio_integrity_tag_size);
static int bio_integrity_tag(struct bio *bio, void *tag_buf, unsigned int len,
int set)
{
- struct bio_integrity_payload *bip = bio->bi_integrity;
+ struct bio_integrity_payload *bip = bio_integrity(bio);
struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
unsigned int nr_sectors;
@@ -310,12 +311,12 @@ static int bio_integrity_generate_verify(struct bio *bio,
int operate)
struct bio_vec *bv;
sector_t sector;
unsigned int sectors, ret = 0, i;
- void *prot_buf = bio->bi_integrity->bip_buf;
+ void *prot_buf = bio_integrity(bio)->bip_buf;
if (operate)
sector = bio->bi_iter.bi_sector;
else
- sector = bio->bi_integrity->bip_iter.bi_sector;
+ sector = bio_integrity(bio)->bip_iter.bi_sector;
bix.disk_name = bio->bi_bdev->bd_disk->disk_name;
bix.sector_size = bi->sector_size;
@@ -511,7 +512,7 @@ static void bio_integrity_verify_fn(struct work_struct
*work)
*/
void bio_integrity_endio(struct bio *bio, int error)
{
- struct bio_integrity_payload *bip = bio->bi_integrity;
+ struct bio_integrity_payload *bip = bio_integrity(bio);
BUG_ON(bip->bip_bio != bio);
@@ -542,7 +543,7 @@ EXPORT_SYMBOL(bio_integrity_endio);
*/
void bio_integrity_advance(struct bio *bio, unsigned int bytes_done)
{
- struct bio_integrity_payload *bip = bio->bi_integrity;
+ struct bio_integrity_payload *bip = bio_integrity(bio);
struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
unsigned bytes = bio_integrity_bytes(bi, bytes_done >> 9);
@@ -564,7 +565,7 @@ EXPORT_SYMBOL(bio_integrity_advance);
void bio_integrity_trim(struct bio *bio, unsigned int offset,
unsigned int sectors)
{
- struct bio_integrity_payload *bip = bio->bi_integrity;
+ struct bio_integrity_payload *bip = bio_integrity(bio);
struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
bio_integrity_advance(bio, offset << 9);
@@ -583,7 +584,7 @@ EXPORT_SYMBOL(bio_integrity_trim);
int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
gfp_t gfp_mask)
{
- struct bio_integrity_payload *bip_src = bio_src->bi_integrity;
+ struct bio_integrity_payload *bip_src = bio_integrity(bio_src);
struct bio_integrity_payload *bip;
BUG_ON(bip_src == NULL);
diff --git a/drivers/scsi/sd_dif.c b/drivers/scsi/sd_dif.c
index a7a691d0af7d..29f0477a8708 100644
--- a/drivers/scsi/sd_dif.c
+++ b/drivers/scsi/sd_dif.c
@@ -383,9 +383,9 @@ void sd_dif_prepare(struct request *rq, sector_t hw_sector,
if (bio_flagged(bio, BIO_MAPPED_INTEGRITY))
break;
- virt = bio->bi_integrity->bip_iter.bi_sector & 0xffffffff;
+ virt = bio_integrity(bio)->bip_iter.bi_sector & 0xffffffff;
- bip_for_each_vec(iv, bio->bi_integrity, iter) {
+ bip_for_each_vec(iv, bio_integrity(bio), iter) {
sdt = kmap_atomic(iv.bv_page)
+ iv.bv_offset;
@@ -434,9 +434,9 @@ void sd_dif_complete(struct scsi_cmnd *scmd, unsigned int
good_bytes)
struct bio_vec iv;
struct bvec_iter iter;
- virt = bio->bi_integrity->bip_iter.bi_sector & 0xffffffff;
+ virt = bio_integrity(bio)->bip_iter.bi_sector & 0xffffffff;
- bip_for_each_vec(iv, bio->bi_integrity, iter) {
+ bip_for_each_vec(iv, bio_integrity(bio), iter) {
sdt = kmap_atomic(iv.bv_page)
+ iv.bv_offset;
diff --git a/include/linux/bio.h b/include/linux/bio.h
index f11dd9efd3d9..1c608a0cbd8e 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -293,6 +293,15 @@ static inline unsigned bio_segments(struct bio *bio)
#define bio_get(bio) atomic_inc(&(bio)->bi_cnt)
#if defined(CONFIG_BLK_DEV_INTEGRITY)
+
+static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
+{
+ if (bio->bi_rw & REQ_INTEGRITY)
+ return bio->bi_integrity;
+
+ return NULL;
+}
+
/*
* bio integrity payload
*/
@@ -660,8 +669,6 @@ struct biovec_slab {
for_each_bio(_bio) \
bip_for_each_vec(_bvl, _bio->bi_integrity, _iter)
-#define bio_integrity(bio) (bio->bi_integrity != NULL)
-
extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t,
unsigned int);
extern void bio_integrity_free(struct bio *);
extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int,
unsigned int);
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 66c2167f04a9..0b7084f7c136 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -78,9 +78,11 @@ struct bio {
struct io_context *bi_ioc;
struct cgroup_subsys_state *bi_css;
#endif
+ union {
#if defined(CONFIG_BLK_DEV_INTEGRITY)
- struct bio_integrity_payload *bi_integrity; /* data integrity */
+ struct bio_integrity_payload *bi_integrity; /* data integrity */
#endif
+ };
