linux-stable/block/bio-integrity.c
Keith Busch c340b990d5 block: support pi with extended metadata
The nvme spec allows protection information formats with metadata
extending beyond the pi field. Use the actual size of the metadata field
for incrementing the buffer.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20220303201312.3255347-2-kbusch@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-03-07 12:48:35 -07:00

464 lines
12 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* bio-integrity.c - bio data integrity extensions
*
* Copyright (C) 2007, 2008, 2009 Oracle Corporation
* Written by: Martin K. Petersen <martin.petersen@oracle.com>
*/
#include <linux/blk-integrity.h>
#include <linux/mempool.h>
#include <linux/export.h>
#include <linux/bio.h>
#include <linux/workqueue.h>
#include <linux/slab.h>
#include "blk.h"
static struct kmem_cache *bip_slab;
static struct workqueue_struct *kintegrityd_wq;
void blk_flush_integrity(void)
{
flush_workqueue(kintegrityd_wq);
}
static void __bio_integrity_free(struct bio_set *bs,
struct bio_integrity_payload *bip)
{
if (bs && mempool_initialized(&bs->bio_integrity_pool)) {
if (bip->bip_vec)
bvec_free(&bs->bvec_integrity_pool, bip->bip_vec,
bip->bip_max_vcnt);
mempool_free(bip, &bs->bio_integrity_pool);
} else {
kfree(bip);
}
}
/**
* bio_integrity_alloc - Allocate integrity payload and attach it to bio
* @bio: bio to attach integrity metadata to
* @gfp_mask: Memory allocation mask
* @nr_vecs: Number of integrity metadata scatter-gather elements
*
* Description: This function prepares a bio for attaching integrity
* metadata. nr_vecs specifies the maximum number of pages containing
* integrity metadata that can be attached.
*/
struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio,
gfp_t gfp_mask,
unsigned int nr_vecs)
{
struct bio_integrity_payload *bip;
struct bio_set *bs = bio->bi_pool;
unsigned inline_vecs;
if (WARN_ON_ONCE(bio_has_crypt_ctx(bio)))
return ERR_PTR(-EOPNOTSUPP);
if (!bs || !mempool_initialized(&bs->bio_integrity_pool)) {
bip = kmalloc(struct_size(bip, bip_inline_vecs, nr_vecs), gfp_mask);
inline_vecs = nr_vecs;
} else {
bip = mempool_alloc(&bs->bio_integrity_pool, gfp_mask);
inline_vecs = BIO_INLINE_VECS;
}
if (unlikely(!bip))
return ERR_PTR(-ENOMEM);
memset(bip, 0, sizeof(*bip));
if (nr_vecs > inline_vecs) {
bip->bip_max_vcnt = nr_vecs;
bip->bip_vec = bvec_alloc(&bs->bvec_integrity_pool,
&bip->bip_max_vcnt, gfp_mask);
if (!bip->bip_vec)
goto err;
} else {
bip->bip_vec = bip->bip_inline_vecs;
bip->bip_max_vcnt = inline_vecs;
}
bip->bip_bio = bio;
bio->bi_integrity = bip;
bio->bi_opf |= REQ_INTEGRITY;
return bip;
err:
__bio_integrity_free(bs, bip);
return ERR_PTR(-ENOMEM);
}
EXPORT_SYMBOL(bio_integrity_alloc);
/**
* 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_BLOCK_INTEGRITY)
kfree(bvec_virt(bip->bip_vec));
__bio_integrity_free(bs, bip);
bio->bi_integrity = NULL;
bio->bi_opf &= ~REQ_INTEGRITY;
}
/**
* bio_integrity_add_page - Attach integrity metadata
* @bio: bio to update
* @page: page containing integrity metadata
* @len: number of bytes of integrity metadata in page
* @offset: start offset within page
*
* Description: Attach a page containing integrity metadata to bio.
*/
int bio_integrity_add_page(struct bio *bio, struct page *page,
unsigned int len, unsigned int offset)
{
struct bio_integrity_payload *bip = bio_integrity(bio);
struct bio_vec *iv;
if (bip->bip_vcnt >= bip->bip_max_vcnt) {
printk(KERN_ERR "%s: bip_vec full\n", __func__);
return 0;
}
iv = bip->bip_vec + bip->bip_vcnt;
if (bip->bip_vcnt &&
bvec_gap_to_prev(bdev_get_queue(bio->bi_bdev),
&bip->bip_vec[bip->bip_vcnt - 1], offset))
return 0;
iv->bv_page = page;
iv->bv_len = len;
iv->bv_offset = offset;
bip->bip_vcnt++;
return len;
}
EXPORT_SYMBOL(bio_integrity_add_page);
/**
* bio_integrity_process - Process integrity metadata for a bio
* @bio: bio to generate/verify integrity metadata for
* @proc_iter: iterator to process
* @proc_fn: Pointer to the relevant processing function
*/
static blk_status_t bio_integrity_process(struct bio *bio,
struct bvec_iter *proc_iter, integrity_processing_fn *proc_fn)
{
struct blk_integrity *bi = blk_get_integrity(bio->bi_bdev->bd_disk);
struct blk_integrity_iter iter;
struct bvec_iter bviter;
struct bio_vec bv;
struct bio_integrity_payload *bip = bio_integrity(bio);
blk_status_t ret = BLK_STS_OK;
iter.disk_name = bio->bi_bdev->bd_disk->disk_name;
iter.interval = 1 << bi->interval_exp;
iter.tuple_size = bi->tuple_size;
iter.seed = proc_iter->bi_sector;
iter.prot_buf = bvec_virt(bip->bip_vec);
__bio_for_each_segment(bv, bio, bviter, *proc_iter) {
void *kaddr = bvec_kmap_local(&bv);
iter.data_buf = kaddr;
iter.data_size = bv.bv_len;
ret = proc_fn(&iter);
kunmap_local(kaddr);
if (ret)
break;
}
return ret;
}
/**
* bio_integrity_prep - Prepare bio for integrity I/O
* @bio: bio to prepare
*
* Description: Checks if the bio already has an integrity payload attached.
* If it does, the payload has been generated by another kernel subsystem,
* and we just pass it through. Otherwise allocates integrity payload.
* The bio must have data direction, target device and start sector set priot
* to calling. In the WRITE case, integrity metadata will be generated using
* the block device's integrity function. In the READ case, the buffer
* will be prepared for DMA and a suitable end_io handler set up.
*/
bool bio_integrity_prep(struct bio *bio)
{
struct bio_integrity_payload *bip;
struct blk_integrity *bi = blk_get_integrity(bio->bi_bdev->bd_disk);
void *buf;
unsigned long start, end;
unsigned int len, nr_pages;
unsigned int bytes, offset, i;
unsigned int intervals;
blk_status_t status;
if (!bi)
return true;
if (bio_op(bio) != REQ_OP_READ && bio_op(bio) != REQ_OP_WRITE)
return true;
if (!bio_sectors(bio))
return true;
/* Already protected? */
if (bio_integrity(bio))
return true;
if (bio_data_dir(bio) == READ) {
if (!bi->profile->verify_fn ||
!(bi->flags & BLK_INTEGRITY_VERIFY))
return true;
} else {
if (!bi->profile->generate_fn ||
!(bi->flags & BLK_INTEGRITY_GENERATE))
return true;
}
intervals = bio_integrity_intervals(bi, bio_sectors(bio));
/* Allocate kernel buffer for protection data */
len = intervals * bi->tuple_size;
buf = kmalloc(len, GFP_NOIO);
status = BLK_STS_RESOURCE;
if (unlikely(buf == NULL)) {
printk(KERN_ERR "could not allocate integrity buffer\n");
goto err_end_io;
}
end = (((unsigned long) buf) + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
start = ((unsigned long) buf) >> PAGE_SHIFT;
nr_pages = end - start;
/* Allocate bio integrity payload and integrity vectors */
bip = bio_integrity_alloc(bio, GFP_NOIO, nr_pages);
if (IS_ERR(bip)) {
printk(KERN_ERR "could not allocate data integrity bioset\n");
kfree(buf);
status = BLK_STS_RESOURCE;
goto err_end_io;
}
bip->bip_flags |= BIP_BLOCK_INTEGRITY;
bip->bip_iter.bi_size = len;
bip_set_seed(bip, bio->bi_iter.bi_sector);
if (bi->flags & BLK_INTEGRITY_IP_CHECKSUM)
bip->bip_flags |= BIP_IP_CHECKSUM;
/* Map it */
offset = offset_in_page(buf);
for (i = 0 ; i < nr_pages ; i++) {
int ret;
bytes = PAGE_SIZE - offset;
if (len <= 0)
break;
if (bytes > len)
bytes = len;
ret = bio_integrity_add_page(bio, virt_to_page(buf),
bytes, offset);
if (ret == 0) {
printk(KERN_ERR "could not attach integrity payload\n");
status = BLK_STS_RESOURCE;
goto err_end_io;
}
if (ret < bytes)
break;
buf += bytes;
len -= bytes;
offset = 0;
}
/* Auto-generate integrity metadata if this is a write */
if (bio_data_dir(bio) == WRITE) {
bio_integrity_process(bio, &bio->bi_iter,
bi->profile->generate_fn);
} else {
bip->bio_iter = bio->bi_iter;
}
return true;
err_end_io:
bio->bi_status = status;
bio_endio(bio);
return false;
}
EXPORT_SYMBOL(bio_integrity_prep);
/**
* bio_integrity_verify_fn - Integrity I/O completion worker
* @work: Work struct stored in bio to be verified
*
* Description: This workqueue function is called to complete a READ
* request. The function verifies the transferred integrity metadata
* and then calls the original bio end_io function.
*/
static void bio_integrity_verify_fn(struct work_struct *work)
{
struct bio_integrity_payload *bip =
container_of(work, struct bio_integrity_payload, bip_work);
struct bio *bio = bip->bip_bio;
struct blk_integrity *bi = blk_get_integrity(bio->bi_bdev->bd_disk);
/*
* At the moment verify is called bio's iterator was advanced
* during split and completion, we need to rewind iterator to
* it's original position.
*/
bio->bi_status = bio_integrity_process(bio, &bip->bio_iter,
bi->profile->verify_fn);
bio_integrity_free(bio);
bio_endio(bio);
}
/**
* __bio_integrity_endio - Integrity I/O completion function
* @bio: Protected bio
*
* Description: Completion for integrity I/O
*
* 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 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->profile->verify_fn) {
INIT_WORK(&bip->bip_work, bio_integrity_verify_fn);
queue_work(kintegrityd_wq, &bip->bip_work);
return false;
}
bio_integrity_free(bio);
return true;
}
/**
* bio_integrity_advance - Advance integrity vector
* @bio: bio whose integrity vector to update
* @bytes_done: number of data bytes that have been completed
*
* Description: This function calculates how many integrity bytes the
* number of completed data bytes correspond to and advances the
* integrity vector accordingly.
*/
void bio_integrity_advance(struct bio *bio, unsigned int bytes_done)
{
struct bio_integrity_payload *bip = bio_integrity(bio);
struct blk_integrity *bi = blk_get_integrity(bio->bi_bdev->bd_disk);
unsigned bytes = bio_integrity_bytes(bi, bytes_done >> 9);
bip->bip_iter.bi_sector += bio_integrity_intervals(bi, bytes_done >> 9);
bvec_iter_advance(bip->bip_vec, &bip->bip_iter, bytes);
}
/**
* bio_integrity_trim - Trim integrity vector
* @bio: bio whose integrity vector to update
*
* Description: Used to trim the integrity vector in a cloned bio.
*/
void bio_integrity_trim(struct bio *bio)
{
struct bio_integrity_payload *bip = bio_integrity(bio);
struct blk_integrity *bi = blk_get_integrity(bio->bi_bdev->bd_disk);
bip->bip_iter.bi_size = bio_integrity_bytes(bi, bio_sectors(bio));
}
EXPORT_SYMBOL(bio_integrity_trim);
/**
* bio_integrity_clone - Callback for cloning bios with integrity metadata
* @bio: New bio
* @bio_src: Original bio
* @gfp_mask: Memory allocation mask
*
* Description: Called to allocate a bip when cloning a bio
*/
int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
gfp_t gfp_mask)
{
struct bio_integrity_payload *bip_src = bio_integrity(bio_src);
struct bio_integrity_payload *bip;
BUG_ON(bip_src == NULL);
bip = bio_integrity_alloc(bio, gfp_mask, bip_src->bip_vcnt);
if (IS_ERR(bip))
return PTR_ERR(bip);
memcpy(bip->bip_vec, bip_src->bip_vec,
bip_src->bip_vcnt * sizeof(struct bio_vec));
bip->bip_vcnt = bip_src->bip_vcnt;
bip->bip_iter = bip_src->bip_iter;
return 0;
}
int bioset_integrity_create(struct bio_set *bs, int pool_size)
{
if (mempool_initialized(&bs->bio_integrity_pool))
return 0;
if (mempool_init_slab_pool(&bs->bio_integrity_pool,
pool_size, bip_slab))
return -1;
if (biovec_init_pool(&bs->bvec_integrity_pool, pool_size)) {
mempool_exit(&bs->bio_integrity_pool);
return -1;
}
return 0;
}
EXPORT_SYMBOL(bioset_integrity_create);
void bioset_integrity_free(struct bio_set *bs)
{
mempool_exit(&bs->bio_integrity_pool);
mempool_exit(&bs->bvec_integrity_pool);
}
void __init bio_integrity_init(void)
{
/*
* 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, 1);
if (!kintegrityd_wq)
panic("Failed to create kintegrityd\n");
bip_slab = kmem_cache_create("bio_integrity_payload",
sizeof(struct bio_integrity_payload) +
sizeof(struct bio_vec) * BIO_INLINE_VECS,
0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
}