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authorJens Axboe <axboe@fb.com>2014-05-19 08:16:41 -0600
committerJens Axboe <axboe@fb.com>2014-05-19 08:34:46 -0600
commitf9c78b2be2cac2a7a397d489275e7d9f9ae785f2 (patch)
treefde918d944e61dc87cc89a71bec7e886832b1829 /fs/bio-integrity.c
parentacb12e0a9c17ae859a05acb116a0c0a7e310c781 (diff)
downloadlwn-f9c78b2be2cac2a7a397d489275e7d9f9ae785f2.tar.gz
lwn-f9c78b2be2cac2a7a397d489275e7d9f9ae785f2.zip
block: move bio.c and bio-integrity.c from fs/ to block/
They really belong in block/, especially now since it's not in drivers/block/ anymore. Additionally, the get_maintainer script gets it wrong when in fs/. Suggested-by: Christoph Hellwig <hch@infradead.org> Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'fs/bio-integrity.c')
-rw-r--r--fs/bio-integrity.c657
1 files changed, 0 insertions, 657 deletions
diff --git a/fs/bio-integrity.c b/fs/bio-integrity.c
deleted file mode 100644
index 9e241063a616..000000000000
--- a/fs/bio-integrity.c
+++ /dev/null
@@ -1,657 +0,0 @@
-/*
- * bio-integrity.c - bio data integrity extensions
- *
- * Copyright (C) 2007, 2008, 2009 Oracle Corporation
- * Written by: Martin K. Petersen <martin.petersen@oracle.com>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License version
- * 2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; see the file COPYING. If not, write to
- * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
- * USA.
- *
- */
-
-#include <linux/blkdev.h>
-#include <linux/mempool.h>
-#include <linux/export.h>
-#include <linux/bio.h>
-#include <linux/workqueue.h>
-#include <linux/slab.h>
-
-#define BIP_INLINE_VECS 4
-
-static struct kmem_cache *bip_slab;
-static struct workqueue_struct *kintegrityd_wq;
-
-/**
- * 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 long idx = BIO_POOL_NONE;
- unsigned inline_vecs;
-
- if (!bs) {
- bip = kmalloc(sizeof(struct bio_integrity_payload) +
- sizeof(struct bio_vec) * nr_vecs, gfp_mask);
- inline_vecs = nr_vecs;
- } else {
- bip = mempool_alloc(bs->bio_integrity_pool, gfp_mask);
- inline_vecs = BIP_INLINE_VECS;
- }
-
- if (unlikely(!bip))
- return NULL;
-
- memset(bip, 0, sizeof(*bip));
-
- if (nr_vecs > inline_vecs) {
- bip->bip_vec = bvec_alloc(gfp_mask, nr_vecs, &idx,
- bs->bvec_integrity_pool);
- if (!bip->bip_vec)
- goto err;
- } else {
- bip->bip_vec = bip->bip_inline_vecs;
- }
-
- bip->bip_slab = idx;
- bip->bip_bio = bio;
- bio->bi_integrity = bip;
-
- return bip;
-err:
- mempool_free(bip, bs->bio_integrity_pool);
- return NULL;
-}
-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->bi_integrity;
- struct bio_set *bs = bio->bi_pool;
-
- if (bip->bip_owns_buf)
- kfree(bip->bip_buf);
-
- if (bs) {
- if (bip->bip_slab != BIO_POOL_NONE)
- bvec_free(bs->bvec_integrity_pool, bip->bip_vec,
- bip->bip_slab);
-
- mempool_free(bip, bs->bio_integrity_pool);
- } else {
- kfree(bip);
- }
-
- bio->bi_integrity = NULL;
-}
-EXPORT_SYMBOL(bio_integrity_free);
-
-static inline unsigned int bip_integrity_vecs(struct bio_integrity_payload *bip)
-{
- if (bip->bip_slab == BIO_POOL_NONE)
- return BIP_INLINE_VECS;
-
- return bvec_nr_vecs(bip->bip_slab);
-}
-
-/**
- * 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->bi_integrity;
- struct bio_vec *iv;
-
- if (bip->bip_vcnt >= bip_integrity_vecs(bip)) {
- printk(KERN_ERR "%s: bip_vec full\n", __func__);
- return 0;
- }
-
- iv = bip->bip_vec + bip->bip_vcnt;
-
- iv->bv_page = page;
- iv->bv_len = len;
- iv->bv_offset = offset;
- bip->bip_vcnt++;
-
- return len;
-}
-EXPORT_SYMBOL(bio_integrity_add_page);
-
-static 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 &&
- (bi->flags & INTEGRITY_FLAG_READ))
- return 1;
-
- if (rw == WRITE && bi->generate_fn != NULL &&
- (bi->flags & INTEGRITY_FLAG_WRITE))
- return 1;
-
- return 0;
-}
-
-/**
- * bio_integrity_enabled - Check whether integrity can be passed
- * @bio: bio to check
- *
- * Description: Determines whether bio_integrity_prep() can be called
- * on this bio or not. bio data direction and target device must be
- * set prior to calling. The functions honors the write_generate and
- * read_verify flags in sysfs.
- */
-int bio_integrity_enabled(struct bio *bio)
-{
- if (!bio_is_rw(bio))
- return 0;
-
- /* Already protected? */
- if (bio_integrity(bio))
- return 0;
-
- return bdev_integrity_enabled(bio->bi_bdev, bio_data_dir(bio));
-}
-EXPORT_SYMBOL(bio_integrity_enabled);
-
-/**
- * bio_integrity_hw_sectors - Convert 512b sectors to hardware ditto
- * @bi: blk_integrity profile for device
- * @sectors: Number of 512 sectors to convert
- *
- * Description: The block layer calculates everything in 512 byte
- * sectors but integrity metadata is done in terms of the hardware
- * sector size of the storage device. Convert the block layer sectors
- * to physical sectors.
- */
-static inline unsigned int bio_integrity_hw_sectors(struct blk_integrity *bi,
- unsigned int sectors)
-{
- /* At this point there are only 512b or 4096b DIF/EPP devices */
- if (bi->sector_size == 4096)
- return sectors >>= 3;
-
- return sectors;
-}
-
-static inline unsigned int bio_integrity_bytes(struct blk_integrity *bi,
- unsigned int sectors)
-{
- return bio_integrity_hw_sectors(bi, sectors) * bi->tuple_size;
-}
-
-/**
- * bio_integrity_tag_size - Retrieve integrity tag space
- * @bio: bio to inspect
- *
- * Description: Returns the maximum number of tag bytes that can be
- * attached to this bio. Filesystems can use this to determine how
- * much metadata to attach to an I/O.
- */
-unsigned int bio_integrity_tag_size(struct bio *bio)
-{
- struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
-
- BUG_ON(bio->bi_iter.bi_size == 0);
-
- return bi->tag_size * (bio->bi_iter.bi_size / bi->sector_size);
-}
-EXPORT_SYMBOL(bio_integrity_tag_size);
-
-static int bio_integrity_tag(struct bio *bio, void *tag_buf, unsigned int len,
- int set)
-{
- struct bio_integrity_payload *bip = bio->bi_integrity;
- struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
- unsigned int nr_sectors;
-
- BUG_ON(bip->bip_buf == NULL);
-
- if (bi->tag_size == 0)
- return -1;
-
- nr_sectors = bio_integrity_hw_sectors(bi,
- DIV_ROUND_UP(len, bi->tag_size));
-
- if (nr_sectors * bi->tuple_size > bip->bip_iter.bi_size) {
- printk(KERN_ERR "%s: tag too big for bio: %u > %u\n", __func__,
- nr_sectors * bi->tuple_size, bip->bip_iter.bi_size);
- return -1;
- }
-
- if (set)
- bi->set_tag_fn(bip->bip_buf, tag_buf, nr_sectors);
- else
- bi->get_tag_fn(bip->bip_buf, tag_buf, nr_sectors);
-
- return 0;
-}
-
-/**
- * bio_integrity_set_tag - Attach a tag buffer to a bio
- * @bio: bio to attach buffer to
- * @tag_buf: Pointer to a buffer containing tag data
- * @len: Length of the included buffer
- *
- * Description: Use this function to tag a bio by leveraging the extra
- * space provided by devices formatted with integrity protection. The
- * size of the integrity buffer must be <= to the size reported by
- * bio_integrity_tag_size().
- */
-int bio_integrity_set_tag(struct bio *bio, void *tag_buf, unsigned int len)
-{
- BUG_ON(bio_data_dir(bio) != WRITE);
-
- return bio_integrity_tag(bio, tag_buf, len, 1);
-}
-EXPORT_SYMBOL(bio_integrity_set_tag);
-
-/**
- * bio_integrity_get_tag - Retrieve a tag buffer from a bio
- * @bio: bio to retrieve buffer from
- * @tag_buf: Pointer to a buffer for the tag data
- * @len: Length of the target buffer
- *
- * Description: Use this function to retrieve the tag buffer from a
- * completed I/O. The size of the integrity buffer must be <= to the
- * size reported by bio_integrity_tag_size().
- */
-int bio_integrity_get_tag(struct bio *bio, void *tag_buf, unsigned int len)
-{
- BUG_ON(bio_data_dir(bio) != READ);
-
- return bio_integrity_tag(bio, tag_buf, len, 0);
-}
-EXPORT_SYMBOL(bio_integrity_get_tag);
-
-/**
- * bio_integrity_generate_verify - Generate/verify integrity metadata for a bio
- * @bio: bio to generate/verify integrity metadata for
- * @operate: operate number, 1 for generate, 0 for verify
- */
-static int bio_integrity_generate_verify(struct bio *bio, int operate)
-{
- struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
- struct blk_integrity_exchg bix;
- struct bio_vec *bv;
- sector_t sector;
- unsigned int sectors, ret = 0, i;
- void *prot_buf = bio->bi_integrity->bip_buf;
-
- if (operate)
- sector = bio->bi_iter.bi_sector;
- else
- sector = bio->bi_integrity->bip_iter.bi_sector;
-
- bix.disk_name = bio->bi_bdev->bd_disk->disk_name;
- bix.sector_size = bi->sector_size;
-
- bio_for_each_segment_all(bv, bio, i) {
- void *kaddr = kmap_atomic(bv->bv_page);
- bix.data_buf = kaddr + bv->bv_offset;
- bix.data_size = bv->bv_len;
- bix.prot_buf = prot_buf;
- bix.sector = sector;
-
- if (operate)
- bi->generate_fn(&bix);
- else {
- ret = bi->verify_fn(&bix);
- if (ret) {
- kunmap_atomic(kaddr);
- return ret;
- }
- }
-
- sectors = bv->bv_len / bi->sector_size;
- sector += sectors;
- prot_buf += sectors * bi->tuple_size;
-
- kunmap_atomic(kaddr);
- }
- return ret;
-}
-
-/**
- * bio_integrity_generate - Generate integrity metadata for a bio
- * @bio: bio to generate integrity metadata for
- *
- * Description: Generates integrity metadata for a bio by calling the
- * block device's generation callback function. The bio must have a
- * bip attached with enough room to accommodate the generated
- * integrity metadata.
- */
-static void bio_integrity_generate(struct bio *bio)
-{
- bio_integrity_generate_verify(bio, 1);
-}
-
-static inline unsigned short blk_integrity_tuple_size(struct blk_integrity *bi)
-{
- if (bi)
- return bi->tuple_size;
-
- return 0;
-}
-
-/**
- * bio_integrity_prep - Prepare bio for integrity I/O
- * @bio: bio to prepare
- *
- * Description: Allocates a buffer for integrity metadata, maps the
- * pages and attaches them to a bio. 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.
- */
-int bio_integrity_prep(struct bio *bio)
-{
- struct bio_integrity_payload *bip;
- struct blk_integrity *bi;
- struct request_queue *q;
- void *buf;
- unsigned long start, end;
- unsigned int len, nr_pages;
- unsigned int bytes, offset, i;
- unsigned int sectors;
-
- bi = bdev_get_integrity(bio->bi_bdev);
- q = bdev_get_queue(bio->bi_bdev);
- BUG_ON(bi == NULL);
- BUG_ON(bio_integrity(bio));
-
- sectors = bio_integrity_hw_sectors(bi, bio_sectors(bio));
-
- /* Allocate kernel buffer for protection data */
- len = sectors * blk_integrity_tuple_size(bi);
- buf = kmalloc(len, GFP_NOIO | q->bounce_gfp);
- if (unlikely(buf == NULL)) {
- printk(KERN_ERR "could not allocate integrity buffer\n");
- return -ENOMEM;
- }
-
- 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 (unlikely(bip == NULL)) {
- printk(KERN_ERR "could not allocate data integrity bioset\n");
- kfree(buf);
- return -EIO;
- }
-
- bip->bip_owns_buf = 1;
- bip->bip_buf = buf;
- bip->bip_iter.bi_size = len;
- bip->bip_iter.bi_sector = bio->bi_iter.bi_sector;
-
- /* 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)
- return 0;
-
- if (ret < bytes)
- break;
-
- buf += bytes;
- len -= bytes;
- offset = 0;
- }
-
- /* Install custom I/O completion handler if read verify is enabled */
- if (bio_data_dir(bio) == READ) {
- bip->bip_end_io = bio->bi_end_io;
- bio->bi_end_io = bio_integrity_endio;
- }
-
- /* Auto-generate integrity metadata if this is a write */
- if (bio_data_dir(bio) == WRITE)
- bio_integrity_generate(bio);
-
- return 0;
-}
-EXPORT_SYMBOL(bio_integrity_prep);
-
-/**
- * bio_integrity_verify - Verify integrity metadata for a bio
- * @bio: bio to verify
- *
- * Description: This function is called to verify the integrity of a
- * bio. The data in the bio io_vec is compared to the integrity
- * metadata returned by the HBA.
- */
-static int bio_integrity_verify(struct bio *bio)
-{
- return bio_integrity_generate_verify(bio, 0);
-}
-
-/**
- * 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;
- int error;
-
- error = bio_integrity_verify(bio);
-
- /* Restore original bio completion handler */
- bio->bi_end_io = bip->bip_end_io;
- bio_endio_nodec(bio, error);
-}
-
-/**
- * bio_integrity_endio - Integrity I/O completion function
- * @bio: Protected bio
- * @error: Pointer to errno
- *
- * 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.
- */
-void bio_integrity_endio(struct bio *bio, int error)
-{
- struct bio_integrity_payload *bip = bio->bi_integrity;
-
- BUG_ON(bip->bip_bio != bio);
-
- /* In case of an I/O error there is no point in verifying the
- * integrity metadata. Restore original bio end_io handler
- * and run it.
- */
- if (error) {
- bio->bi_end_io = bip->bip_end_io;
- bio_endio(bio, error);
-
- return;
- }
-
- INIT_WORK(&bip->bip_work, bio_integrity_verify_fn);
- queue_work(kintegrityd_wq, &bip->bip_work);
-}
-EXPORT_SYMBOL(bio_integrity_endio);
-
-/**
- * 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->bi_integrity;
- struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
- unsigned bytes = bio_integrity_bytes(bi, bytes_done >> 9);
-
- bvec_iter_advance(bip->bip_vec, &bip->bip_iter, bytes);
-}
-EXPORT_SYMBOL(bio_integrity_advance);
-
-/**
- * bio_integrity_trim - Trim integrity vector
- * @bio: bio whose integrity vector to update
- * @offset: offset to first data sector
- * @sectors: number of data sectors
- *
- * Description: Used to trim the integrity vector in a cloned bio.
- * The ivec will be advanced corresponding to 'offset' data sectors
- * and the length will be truncated corresponding to 'len' data
- * sectors.
- */
-void bio_integrity_trim(struct bio *bio, unsigned int offset,
- unsigned int sectors)
-{
- struct bio_integrity_payload *bip = bio->bi_integrity;
- struct blk_integrity *bi = bdev_get_integrity(bio->bi_bdev);
-
- bio_integrity_advance(bio, offset << 9);
- bip->bip_iter.bi_size = bio_integrity_bytes(bi, sectors);
-}
-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_src->bi_integrity;
- struct bio_integrity_payload *bip;
-
- BUG_ON(bip_src == NULL);
-
- bip = bio_integrity_alloc(bio, gfp_mask, bip_src->bip_vcnt);
-
- if (bip == NULL)
- return -EIO;
-
- 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;
-}
-EXPORT_SYMBOL(bio_integrity_clone);
-
-int bioset_integrity_create(struct bio_set *bs, int pool_size)
-{
- if (bs->bio_integrity_pool)
- return 0;
-
- bs->bio_integrity_pool = mempool_create_slab_pool(pool_size, bip_slab);
- if (!bs->bio_integrity_pool)
- return -1;
-
- bs->bvec_integrity_pool = biovec_create_pool(pool_size);
- if (!bs->bvec_integrity_pool) {
- mempool_destroy(bs->bio_integrity_pool);
- return -1;
- }
-
- return 0;
-}
-EXPORT_SYMBOL(bioset_integrity_create);
-
-void bioset_integrity_free(struct bio_set *bs)
-{
- if (bs->bio_integrity_pool)
- mempool_destroy(bs->bio_integrity_pool);
-
- if (bs->bvec_integrity_pool)
- mempool_destroy(bs->bvec_integrity_pool);
-}
-EXPORT_SYMBOL(bioset_integrity_free);
-
-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) * BIP_INLINE_VECS,
- 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
- if (!bip_slab)
- panic("Failed to create slab\n");
-}