1

block: don't free submitter owned integrity payload on I/O completion

Currently __bio_integrity_endio frees the integrity payload unless it is
explicitly marked as user-mapped.  This means in-kernel callers that
allocate their own integrity payload never get to see it on I/O
completion.  The current two users don't need it as they just pre-mapped
PI tuples received over the network, but this limits uses of integrity
data lot.

Change bio_integrity_endio to call __bio_integrity_endio for block layer
generated integrity data only, and leave freeing of submitter
allocated integrity data to bio_uninit which also gets called from
the final bio_put.  This requires that unmapping user mapped or copied
integrity data is now always done by the caller, and the special
BIP_INTEGRITY_USER flag can go away.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240702151047.1746127-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2024-07-02 17:10:23 +02:00 committed by Jens Axboe
parent f8924374fd
commit 85253bac4d
3 changed files with 34 additions and 39 deletions

View File

@ -22,9 +22,17 @@ void blk_flush_integrity(void)
flush_workqueue(kintegrityd_wq);
}
static void __bio_integrity_free(struct bio_set *bs,
struct bio_integrity_payload *bip)
/**
* bio_integrity_free - Free bio integrity payload
* @bio: bio containing bip to be freed
*
* Description: Free the integrity portion of a bio.
*/
void bio_integrity_free(struct bio *bio)
{
struct bio_integrity_payload *bip = bio_integrity(bio);
struct bio_set *bs = bio->bi_pool;
if (bs && mempool_initialized(&bs->bio_integrity_pool)) {
if (bip->bip_vec)
bvec_free(&bs->bvec_integrity_pool, bip->bip_vec,
@ -33,6 +41,8 @@ static void __bio_integrity_free(struct bio_set *bs,
} else {
kfree(bip);
}
bio->bi_integrity = NULL;
bio->bi_opf &= ~REQ_INTEGRITY;
}
/**
@ -86,7 +96,10 @@ struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio,
return bip;
err:
__bio_integrity_free(bs, bip);
if (bs && mempool_initialized(&bs->bio_integrity_pool))
mempool_free(bip, &bs->bio_integrity_pool);
else
kfree(bip);
return ERR_PTR(-ENOMEM);
}
EXPORT_SYMBOL(bio_integrity_alloc);
@ -132,28 +145,6 @@ static void bio_integrity_unmap_user(struct bio_integrity_payload *bip)
bio_integrity_unpin_bvec(bip->bip_vec, bip->bip_max_vcnt, dirty);
}
/**
* bio_integrity_free - Free bio integrity payload
* @bio: bio containing bip to be freed
*
* Description: Used to free the integrity portion of a bio. Usually
* called from bio_free().
*/
void bio_integrity_free(struct bio *bio)
{
struct bio_integrity_payload *bip = bio_integrity(bio);
struct bio_set *bs = bio->bi_pool;
if (bip->bip_flags & BIP_INTEGRITY_USER)
return;
if (bip->bip_flags & BIP_BLOCK_INTEGRITY)
kfree(bvec_virt(bip->bip_vec));
__bio_integrity_free(bs, bip);
bio->bi_integrity = NULL;
bio->bi_opf &= ~REQ_INTEGRITY;
}
/**
* bio_integrity_unmap_free_user - Unmap and free bio user integrity payload
* @bio: bio containing bip to be unmapped and freed
@ -165,14 +156,9 @@ void bio_integrity_free(struct bio *bio)
void bio_integrity_unmap_free_user(struct bio *bio)
{
struct bio_integrity_payload *bip = bio_integrity(bio);
struct bio_set *bs = bio->bi_pool;
if (WARN_ON_ONCE(!(bip->bip_flags & BIP_INTEGRITY_USER)))
return;
bio_integrity_unmap_user(bip);
__bio_integrity_free(bs, bip);
bio->bi_integrity = NULL;
bio->bi_opf &= ~REQ_INTEGRITY;
bio_integrity_free(bio);
}
/**
@ -273,7 +259,7 @@ static int bio_integrity_copy_user(struct bio *bio, struct bio_vec *bvec,
goto free_bip;
}
bip->bip_flags |= BIP_INTEGRITY_USER | BIP_COPY_USER;
bip->bip_flags |= BIP_COPY_USER;
bip->bip_iter.bi_sector = seed;
bip->bip_vcnt = nr_vecs;
return 0;
@ -294,7 +280,6 @@ static int bio_integrity_init_user(struct bio *bio, struct bio_vec *bvec,
return PTR_ERR(bip);
memcpy(bip->bip_vec, bvec, nr_vecs * sizeof(*bvec));
bip->bip_flags |= BIP_INTEGRITY_USER;
bip->bip_iter.bi_sector = seed;
bip->bip_iter.bi_size = len;
bip->bip_vcnt = nr_vecs;
@ -502,6 +487,8 @@ static void bio_integrity_verify_fn(struct work_struct *work)
struct bio *bio = bip->bip_bio;
blk_integrity_verify(bio);
kfree(bvec_virt(bip->bip_vec));
bio_integrity_free(bio);
bio_endio(bio);
}
@ -522,13 +509,13 @@ bool __bio_integrity_endio(struct bio *bio)
struct blk_integrity *bi = blk_get_integrity(bio->bi_bdev->bd_disk);
struct bio_integrity_payload *bip = bio_integrity(bio);
if (bio_op(bio) == REQ_OP_READ && !bio->bi_status &&
(bip->bip_flags & BIP_BLOCK_INTEGRITY) && bi->csum_type) {
if (bio_op(bio) == REQ_OP_READ && !bio->bi_status && bi->csum_type) {
INIT_WORK(&bip->bip_work, bio_integrity_verify_fn);
queue_work(kintegrityd_wq, &bip->bip_work);
return false;
}
kfree(bvec_virt(bip->bip_vec));
bio_integrity_free(bio);
return true;
}

View File

@ -202,11 +202,20 @@ static inline unsigned int blk_queue_get_max_sectors(struct request *rq)
#ifdef CONFIG_BLK_DEV_INTEGRITY
void blk_flush_integrity(void);
bool __bio_integrity_endio(struct bio *);
void bio_integrity_free(struct bio *bio);
/*
* Integrity payloads can either be owned by the submitter, in which case
* bio_uninit will free them, or owned and generated by the block layer,
* in which case we'll verify them here (for reads) and free them before
* the bio is handed back to the submitted.
*/
bool __bio_integrity_endio(struct bio *bio);
static inline bool bio_integrity_endio(struct bio *bio)
{
if (bio_integrity(bio))
struct bio_integrity_payload *bip = bio_integrity(bio);
if (bip && (bip->bip_flags & BIP_BLOCK_INTEGRITY))
return __bio_integrity_endio(bio);
return true;
}

View File

@ -10,8 +10,7 @@ enum bip_flags {
BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
BIP_INTEGRITY_USER = 1 << 5, /* Integrity payload is user address */
BIP_COPY_USER = 1 << 6, /* Kernel bounce buffer in use */
BIP_COPY_USER = 1 << 5, /* Kernel bounce buffer in use */
};
struct bio_integrity_payload {