Commit 7ba1ba12 authored by Martin K. Petersen's avatar Martin K. Petersen Committed by Jens Axboe

block: Block layer data integrity support

Some block devices support verifying the integrity of requests by way
of checksums or other protection information that is submitted along
with the I/O.

This patch implements support for generating and verifying integrity
metadata, as well as correctly merging, splitting and cloning bios and
requests that have this extra information attached.

See Documentation/block/data-integrity.txt for more information.
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
parent 51d654e1
......@@ -81,6 +81,18 @@ config BLK_DEV_BSG
If unsure, say N.
config BLK_DEV_INTEGRITY
bool "Block layer data integrity support"
---help---
Some storage devices allow extra information to be
stored/retrieved to help protect the data. The block layer
data integrity option provides hooks which can be used by
filesystems to ensure better data integrity.
Say yes here if you have a storage device that provides the
T10/SCSI Data Integrity Field or the T13/ATA External Path
Protection. If in doubt, say N.
endif # BLOCK
config BLOCK_COMPAT
......
......@@ -14,3 +14,4 @@ obj-$(CONFIG_IOSCHED_CFQ) += cfq-iosched.o
obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o
obj-$(CONFIG_BLOCK_COMPAT) += compat_ioctl.o
obj-$(CONFIG_BLK_DEV_INTEGRITY) += blk-integrity.o
......@@ -143,6 +143,10 @@ static void req_bio_endio(struct request *rq, struct bio *bio,
bio->bi_size -= nbytes;
bio->bi_sector += (nbytes >> 9);
if (bio_integrity(bio))
bio_integrity_advance(bio, nbytes);
if (bio->bi_size == 0)
bio_endio(bio, error);
} else {
......@@ -1381,6 +1385,9 @@ static inline void __generic_make_request(struct bio *bio)
*/
blk_partition_remap(bio);
if (bio_integrity_enabled(bio) && bio_integrity_prep(bio))
goto end_io;
if (old_sector != -1)
blk_add_trace_remap(q, bio, old_dev, bio->bi_sector,
old_sector);
......
This diff is collapsed.
......@@ -441,6 +441,9 @@ static int attempt_merge(struct request_queue *q, struct request *req,
|| next->special)
return 0;
if (blk_integrity_rq(req) != blk_integrity_rq(next))
return 0;
/*
* If we are allowed to merge, then append bio list
* from next to rq and release next. merge_requests_fn
......
......@@ -51,4 +51,12 @@ static inline int queue_congestion_off_threshold(struct request_queue *q)
return q->nr_congestion_off;
}
#if defined(CONFIG_BLK_DEV_INTEGRITY)
#define rq_for_each_integrity_segment(bvl, _rq, _iter) \
__rq_for_each_bio(_iter.bio, _rq) \
bip_for_each_vec(bvl, _iter.bio->bi_integrity, _iter.i)
#endif /* BLK_DEV_INTEGRITY */
#endif
......@@ -86,6 +86,12 @@ int elv_rq_merge_ok(struct request *rq, struct bio *bio)
if (rq->rq_disk != bio->bi_bdev->bd_disk || rq->special)
return 0;
/*
* only merge integrity protected bio into ditto rq
*/
if (bio_integrity(bio) != blk_integrity_rq(rq))
return 0;
if (!elv_iosched_allow_merge(rq, bio))
return 0;
......
......@@ -19,6 +19,7 @@ else
obj-y += no-block.o
endif
obj-$(CONFIG_BLK_DEV_INTEGRITY) += bio-integrity.o
obj-$(CONFIG_INOTIFY) += inotify.o
obj-$(CONFIG_INOTIFY_USER) += inotify_user.o
obj-$(CONFIG_EPOLL) += eventpoll.o
......
This diff is collapsed.
......@@ -50,6 +50,11 @@ static struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly = {
*/
struct bio_set *fs_bio_set;
unsigned int bvec_nr_vecs(unsigned short idx)
{
return bvec_slabs[idx].nr_vecs;
}
struct bio_vec *bvec_alloc_bs(gfp_t gfp_mask, int nr, unsigned long *idx, struct bio_set *bs)
{
struct bio_vec *bvl;
......@@ -91,6 +96,9 @@ void bio_free(struct bio *bio, struct bio_set *bio_set)
mempool_free(bio->bi_io_vec, bio_set->bvec_pools[pool_idx]);
}
if (bio_integrity(bio))
bio_integrity_free(bio, bio_set);
mempool_free(bio, bio_set->bio_pool);
}
......@@ -249,9 +257,19 @@ struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask)
{
struct bio *b = bio_alloc_bioset(gfp_mask, bio->bi_max_vecs, fs_bio_set);
if (b) {
b->bi_destructor = bio_fs_destructor;
__bio_clone(b, bio);
if (!b)
return NULL;
b->bi_destructor = bio_fs_destructor;
__bio_clone(b, bio);
if (bio_integrity(bio)) {
int ret;
ret = bio_integrity_clone(b, bio, fs_bio_set);
if (ret < 0)
return NULL;
}
return b;
......@@ -1223,6 +1241,9 @@ struct bio_pair *bio_split(struct bio *bi, mempool_t *pool, int first_sectors)
bp->bio1.bi_private = bi;
bp->bio2.bi_private = pool;
if (bio_integrity(bi))
bio_integrity_split(bi, bp, first_sectors);
return bp;
}
......@@ -1264,6 +1285,7 @@ void bioset_free(struct bio_set *bs)
if (bs->bio_pool)
mempool_destroy(bs->bio_pool);
bioset_integrity_free(bs);
biovec_free_pools(bs);
kfree(bs);
......@@ -1280,6 +1302,9 @@ struct bio_set *bioset_create(int bio_pool_size, int bvec_pool_size)
if (!bs->bio_pool)
goto bad;
if (bioset_integrity_create(bs, bio_pool_size))
goto bad;
if (!biovec_create_pools(bs, bvec_pool_size))
return bs;
......@@ -1306,6 +1331,7 @@ static int __init init_bio(void)
{
bio_slab = KMEM_CACHE(bio, SLAB_HWCACHE_ALIGN|SLAB_PANIC);
bio_integrity_init_slab();
biovec_init_slabs();
fs_bio_set = bioset_create(BIO_POOL_SIZE, 2);
......
......@@ -64,6 +64,7 @@ struct bio_vec {
struct bio_set;
struct bio;
struct bio_integrity_payload;
typedef void (bio_end_io_t) (struct bio *, int);
typedef void (bio_destructor_t) (struct bio *);
......@@ -112,6 +113,9 @@ struct bio {
atomic_t bi_cnt; /* pin count */
void *bi_private;
#if defined(CONFIG_BLK_DEV_INTEGRITY)
struct bio_integrity_payload *bi_integrity; /* data integrity */
#endif
bio_destructor_t *bi_destructor; /* destructor */
};
......@@ -271,6 +275,29 @@ static inline void *bio_data(struct bio *bio)
*/
#define bio_get(bio) atomic_inc(&(bio)->bi_cnt)
#if defined(CONFIG_BLK_DEV_INTEGRITY)
/*
* bio integrity payload
*/
struct bio_integrity_payload {
struct bio *bip_bio; /* parent bio */
struct bio_vec *bip_vec; /* integrity data vector */
sector_t bip_sector; /* virtual start sector */
void *bip_buf; /* generated integrity data */
bio_end_io_t *bip_end_io; /* saved I/O completion fn */
int bip_error; /* saved I/O error */
unsigned int bip_size;
unsigned short bip_pool; /* pool the ivec came from */
unsigned short bip_vcnt; /* # of integrity bio_vecs */
unsigned short bip_idx; /* current bip_vec index */
struct work_struct bip_work; /* I/O completion */
};
#endif /* CONFIG_BLK_DEV_INTEGRITY */
/*
* A bio_pair is used when we need to split a bio.
......@@ -283,10 +310,14 @@ static inline void *bio_data(struct bio *bio)
* in bio2.bi_private
*/
struct bio_pair {
struct bio bio1, bio2;
struct bio_vec bv1, bv2;
atomic_t cnt;
int error;
struct bio bio1, bio2;
struct bio_vec bv1, bv2;
#if defined(CONFIG_BLK_DEV_INTEGRITY)
struct bio_integrity_payload bip1, bip2;
struct bio_vec iv1, iv2;
#endif
atomic_t cnt;
int error;
};
extern struct bio_pair *bio_split(struct bio *bi, mempool_t *pool,
int first_sectors);
......@@ -334,6 +365,7 @@ extern struct bio *bio_copy_user_iov(struct request_queue *, struct sg_iovec *,
extern int bio_uncopy_user(struct bio *);
void zero_fill_bio(struct bio *bio);
extern struct bio_vec *bvec_alloc_bs(gfp_t, int, unsigned long *, struct bio_set *);
extern unsigned int bvec_nr_vecs(unsigned short idx);
/*
* bio_set is used to allow other portions of the IO system to
......@@ -346,6 +378,9 @@ extern struct bio_vec *bvec_alloc_bs(gfp_t, int, unsigned long *, struct bio_set
struct bio_set {
mempool_t *bio_pool;
#if defined(CONFIG_BLK_DEV_INTEGRITY)
mempool_t *bio_integrity_pool;
#endif
mempool_t *bvec_pools[BIOVEC_NR_POOLS];
};
......@@ -410,5 +445,56 @@ static inline char *__bio_kmap_irq(struct bio *bio, unsigned short idx,
__bio_kmap_irq((bio), (bio)->bi_idx, (flags))
#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
#if defined(CONFIG_BLK_DEV_INTEGRITY)
#define bip_vec_idx(bip, idx) (&(bip->bip_vec[(idx)]))
#define bip_vec(bip) bip_vec_idx(bip, 0)
#define __bip_for_each_vec(bvl, bip, i, start_idx) \
for (bvl = bip_vec_idx((bip), (start_idx)), i = (start_idx); \
i < (bip)->bip_vcnt; \
bvl++, i++)
#define bip_for_each_vec(bvl, bip, i) \
__bip_for_each_vec(bvl, bip, i, (bip)->bip_idx)
#define bio_integrity(bio) ((bio)->bi_integrity ? 1 : 0)
extern struct bio_integrity_payload *bio_integrity_alloc_bioset(struct bio *, gfp_t, unsigned int, struct bio_set *);
extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int);
extern void bio_integrity_free(struct bio *, struct bio_set *);
extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
extern int bio_integrity_enabled(struct bio *bio);
extern int bio_integrity_set_tag(struct bio *, void *, unsigned int);
extern int bio_integrity_get_tag(struct bio *, void *, unsigned int);
extern int bio_integrity_prep(struct bio *);
extern void bio_integrity_endio(struct bio *, int);
extern void bio_integrity_advance(struct bio *, unsigned int);
extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
extern void bio_integrity_split(struct bio *, struct bio_pair *, int);
extern int bio_integrity_clone(struct bio *, struct bio *, struct bio_set *);
extern int bioset_integrity_create(struct bio_set *, int);
extern void bioset_integrity_free(struct bio_set *);
extern void bio_integrity_init_slab(void);
#else /* CONFIG_BLK_DEV_INTEGRITY */
#define bio_integrity(a) (0)
#define bioset_integrity_create(a, b) (0)
#define bio_integrity_prep(a) (0)
#define bio_integrity_enabled(a) (0)
#define bio_integrity_clone(a, b, c) (0)
#define bioset_integrity_free(a) do { } while (0)
#define bio_integrity_free(a, b) do { } while (0)
#define bio_integrity_endio(a, b) do { } while (0)
#define bio_integrity_advance(a, b) do { } while (0)
#define bio_integrity_trim(a, b, c) do { } while (0)
#define bio_integrity_split(a, b, c) do { } while (0)
#define bio_integrity_set_tag(a, b, c) do { } while (0)
#define bio_integrity_get_tag(a, b, c) do { } while (0)
#define bio_integrity_init_slab(a) do { } while (0)
#endif /* CONFIG_BLK_DEV_INTEGRITY */
#endif /* CONFIG_BLOCK */
#endif /* __LINUX_BIO_H */
......@@ -112,6 +112,7 @@ enum rq_flag_bits {
__REQ_ALLOCED, /* request came from our alloc pool */
__REQ_RW_META, /* metadata io request */
__REQ_COPY_USER, /* contains copies of user pages */
__REQ_INTEGRITY, /* integrity metadata has been remapped */
__REQ_NR_BITS, /* stops here */
};
......@@ -134,6 +135,7 @@ enum rq_flag_bits {
#define REQ_ALLOCED (1 << __REQ_ALLOCED)
#define REQ_RW_META (1 << __REQ_RW_META)
#define REQ_COPY_USER (1 << __REQ_COPY_USER)
#define REQ_INTEGRITY (1 << __REQ_INTEGRITY)
#define BLK_MAX_CDB 16
......@@ -865,6 +867,109 @@ void kblockd_flush_work(struct work_struct *work);
MODULE_ALIAS("block-major-" __stringify(major) "-*")
#if defined(CONFIG_BLK_DEV_INTEGRITY)
#define INTEGRITY_FLAG_READ 1 /* verify data integrity on read */
#define INTEGRITY_FLAG_WRITE 2 /* generate data integrity on write */
struct blk_integrity_exchg {
void *prot_buf;
void *data_buf;
sector_t sector;
unsigned int data_size;
unsigned short sector_size;
const char *disk_name;
};
typedef void (integrity_gen_fn) (struct blk_integrity_exchg *);
typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *);
typedef void (integrity_set_tag_fn) (void *, void *, unsigned int);
typedef void (integrity_get_tag_fn) (void *, void *, unsigned int);
struct blk_integrity {
integrity_gen_fn *generate_fn;
integrity_vrfy_fn *verify_fn;
integrity_set_tag_fn *set_tag_fn;
integrity_get_tag_fn *get_tag_fn;
unsigned short flags;
unsigned short tuple_size;
unsigned short sector_size;
unsigned short tag_size;
const char *name;
struct kobject kobj;
};
extern int blk_integrity_register(struct gendisk *, struct blk_integrity *);
extern void blk_integrity_unregister(struct gendisk *);
extern int blk_integrity_compare(struct block_device *, struct block_device *);
extern int blk_rq_map_integrity_sg(struct request *, struct scatterlist *);
extern int blk_rq_count_integrity_sg(struct request *);
static inline unsigned short blk_integrity_tuple_size(struct blk_integrity *bi)
{
if (bi)
return bi->tuple_size;
return 0;
}
static inline struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
{
return bdev->bd_disk->integrity;
}
static inline unsigned int bdev_get_tag_size(struct block_device *bdev)
{
struct blk_integrity *bi = bdev_get_integrity(bdev);
if (bi)
return bi->tag_size;
return 0;
}
static inline int bdev_integrity_enabled(struct block_device *bdev, int rw)
{
struct blk_integrity *bi = bdev_get_integrity(bdev);
if (bi == NULL)
return 0;
if (rw == READ && bi->verify_fn != NULL &&
test_bit(INTEGRITY_FLAG_READ, &bi->flags))
return 1;
if (rw == WRITE && bi->generate_fn != NULL &&
test_bit(INTEGRITY_FLAG_WRITE, &bi->flags))
return 1;
return 0;
}
static inline int blk_integrity_rq(struct request *rq)
{
BUG_ON(rq->bio == NULL);
return bio_integrity(rq->bio);
}
#else /* CONFIG_BLK_DEV_INTEGRITY */
#define blk_integrity_rq(rq) (0)
#define blk_rq_count_integrity_sg(a) (0)
#define blk_rq_map_integrity_sg(a, b) (0)
#define bdev_get_integrity(a) (0)
#define bdev_get_tag_size(a) (0)
#define blk_integrity_compare(a, b) (0)
#define blk_integrity_register(a, b) (0)
#define blk_integrity_unregister(a) do { } while (0);
#endif /* CONFIG_BLK_DEV_INTEGRITY */
#else /* CONFIG_BLOCK */
/*
* stubs for when the block layer is configured out
......
......@@ -141,6 +141,9 @@ struct gendisk {
struct disk_stats dkstats;
#endif
struct work_struct async_notify;
#ifdef CONFIG_BLK_DEV_INTEGRITY
struct blk_integrity *integrity;
#endif
};
/*
......
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