diff options
Diffstat (limited to 'block/bio-integrity-auto.c')
| -rw-r--r-- | block/bio-integrity-auto.c | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/block/bio-integrity-auto.c b/block/bio-integrity-auto.c new file mode 100644 index 000000000..9456dcffd --- /dev/null +++ b/block/bio-integrity-auto.c @@ -0,0 +1,127 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2007, 2008, 2009 Oracle Corporation + * Written by: Martin K. Petersen <martin.petersen@oracle.com> + * + * Automatically generate and verify integrity data on PI capable devices if the + * bio submitter didn't provide PI itself. This ensures that kernel verifies + * data integrity even if the file system (or other user of the block device) is + * not aware of PI. + */ +#include <linux/blk-integrity.h> +#include <linux/t10-pi.h> +#include <linux/workqueue.h> +#include "blk.h" + +struct bio_integrity_data { + struct bio *bio; + struct bvec_iter saved_bio_iter; + struct work_struct work; + struct bio_integrity_payload bip; + struct bio_vec bvec; +}; + +static struct kmem_cache *bid_slab; +static mempool_t bid_pool; +static struct workqueue_struct *kintegrityd_wq; + +static void bio_integrity_finish(struct bio_integrity_data *bid) +{ + bid->bio->bi_integrity = NULL; + bid->bio->bi_opf &= ~REQ_INTEGRITY; + bio_integrity_free_buf(&bid->bip); + mempool_free(bid, &bid_pool); +} + +static void bio_integrity_verify_fn(struct work_struct *work) +{ + struct bio_integrity_data *bid = + container_of(work, struct bio_integrity_data, work); + struct bio *bio = bid->bio; + + bio->bi_status = bio_integrity_verify(bio, &bid->saved_bio_iter); + bio_integrity_finish(bid); + bio_endio(bio); +} + +/** + * __bio_integrity_endio - Integrity I/O completion function + * @bio: Protected bio + * + * Normally I/O completion is done in interrupt context. However, verifying I/O + * integrity is a time-consuming task which must be run in process context. + * + * This function postpones completion accordingly. + */ +bool __bio_integrity_endio(struct bio *bio) +{ + struct bio_integrity_payload *bip = bio_integrity(bio); + struct bio_integrity_data *bid = + container_of(bip, struct bio_integrity_data, bip); + + if (bio_op(bio) == REQ_OP_READ && !bio->bi_status && + (bip->bip_flags & BIP_CHECK_FLAGS)) { + INIT_WORK(&bid->work, bio_integrity_verify_fn); + queue_work(kintegrityd_wq, &bid->work); + return false; + } + + bio_integrity_finish(bid); + return true; +} + +/** + * bio_integrity_prep - Prepare bio for integrity I/O + * @bio: bio to prepare + * @action: preparation action needed (BI_ACT_*) + * + * Allocate the integrity payload. For writes, generate the integrity metadata + * and for reads, setup the completion handler to verify the metadata. + * + * This is used for bios that do not have user integrity payloads attached. + */ +void bio_integrity_prep(struct bio *bio, unsigned int action) +{ + struct bio_integrity_data *bid; + + bid = mempool_alloc(&bid_pool, GFP_NOIO); + bio_integrity_init(bio, &bid->bip, &bid->bvec, 1); + bid->bio = bio; + bid->bip.bip_flags |= BIP_BLOCK_INTEGRITY; + bio_integrity_alloc_buf(bio, GFP_NOIO, action & BI_ACT_ZERO); + if (action & BI_ACT_CHECK) + bio_integrity_setup_default(bio); + + /* Auto-generate integrity metadata if this is a write */ + if (bio_data_dir(bio) == WRITE && (bid->bip.bip_flags & BIP_CHECK_FLAGS)) + bio_integrity_generate(bio); + else + bid->saved_bio_iter = bio->bi_iter; +} +EXPORT_SYMBOL(bio_integrity_prep); + +void blk_flush_integrity(void) +{ + flush_workqueue(kintegrityd_wq); +} + +static int __init blk_integrity_auto_init(void) +{ + bid_slab = kmem_cache_create("bio_integrity_data", + sizeof(struct bio_integrity_data), 0, + SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL); + + if (mempool_init_slab_pool(&bid_pool, BIO_POOL_SIZE, bid_slab)) + panic("bio: can't create integrity pool\n"); + + /* + * kintegrityd won't block much but may burn a lot of CPU cycles. + * Make it highpri CPU intensive wq with max concurrency of 1. + */ + kintegrityd_wq = alloc_workqueue("kintegrityd", WQ_MEM_RECLAIM | + WQ_HIGHPRI | WQ_CPU_INTENSIVE | WQ_PERCPU, 1); + if (!kintegrityd_wq) + panic("Failed to create kintegrityd\n"); + return 0; +} +subsys_initcall(blk_integrity_auto_init); |