Commit 85253bac authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

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: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: default avatarKanchan Joshi <joshi.k@samsung.com>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240702151047.1746127-6-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent f8924374

block/bio-integrity.c

+22 −35
Original line number Diff line number Diff line
@@ -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;

}

block/blk.h

+11 −2
Original line number Diff line number Diff line
@@ -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;

}

include/linux/bio-integrity.h

+1 −2
Original line number Diff line number Diff line
@@ -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 {