[PATCH v11 10/10] block: add support to pass user meta buffer

Anuj Gupta
2024-11-28T11:46:34Z

From: Kanchan Joshi <joshi.k@samsung.com>

If an iocb contains metadata, extract that and prepare the bip.
Based on flags specified by the user, set corresponding guard/app/ref
tags to be checked in bip.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anuj Gupta <anuj20.g@samsung.com>
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
---
block/bio-integrity.c | 50 +++++++++++++++++++++++++++++++++++
block/fops.c | 45 ++++++++++++++++++++++++-------
include/linux/bio-integrity.h | 7 +++++
3 files changed, 92 insertions(+), 10 deletions(-)

diff --git a/block/bio-integrity.c b/block/bio-integrity.c
index 3bee43b87001..5d81ad9a3d20 100644
--- a/block/bio-integrity.c
+++ b/block/bio-integrity.c
@@ -364,6 +364,55 @@ int bio_integrity_map_user(struct bio *bio, struct iov_iter *iter)
return ret;
}

+static void bio_uio_meta_to_bip(struct bio *bio, struct uio_meta *meta)
+{
+ struct bio_integrity_payload *bip = bio_integrity(bio);
+
+ if (meta->flags & IO_INTEGRITY_CHK_GUARD)
+ bip->bip_flags |= BIP_CHECK_GUARD;
+ if (meta->flags & IO_INTEGRITY_CHK_APPTAG)
+ bip->bip_flags |= BIP_CHECK_APPTAG;
+ if (meta->flags & IO_INTEGRITY_CHK_REFTAG)
+ bip->bip_flags |= BIP_CHECK_REFTAG;
+
+ bip->app_tag = meta->app_tag;
+}
+
+int bio_integrity_map_iter(struct bio *bio, struct uio_meta *meta)
+{
+ struct blk_integrity *bi = blk_get_integrity(bio->bi_bdev->bd_disk);
+ unsigned int integrity_bytes;
+ int ret;
+ struct iov_iter it;
+
+ if (!bi)
+ return -EINVAL;
+ /*
+ * original meta iterator can be bigger.
+ * process integrity info corresponding to current data buffer only.
+ */
+ it = meta->iter;
+ integrity_bytes = bio_integrity_bytes(bi, bio_sectors(bio));
+ if (it.count < integrity_bytes)
+ return -EINVAL;
+
+ /* should fit into two bytes */
+ BUILD_BUG_ON(IO_INTEGRITY_VALID_FLAGS >= (1 << 16));
+
+ if (meta->flags && (meta->flags & ~IO_INTEGRITY_VALID_FLAGS))
+ return -EINVAL;
+
+ it.count = integrity_bytes;
+ ret = bio_integrity_map_user(bio, &it);
+ if (!ret) {
+ bio_uio_meta_to_bip(bio, meta);
+ bip_set_seed(bio_integrity(bio), meta->seed);
+ iov_iter_advance(&meta->iter, integrity_bytes);
+ meta->seed += bio_integrity_intervals(bi, bio_sectors(bio));
+ }
+ return ret;
+}
+
/**
* bio_integrity_prep - Prepare bio for integrity I/O
* @bio: bio to prepare
@@ -564,6 +613,7 @@ int bio_integrity_clone(struct bio *bio, struct bio *bio_src,
bip->bip_vec = bip_src->bip_vec;
bip->bip_iter = bip_src->bip_iter;
bip->bip_flags = bip_src->bip_flags & BIP_CLONE_FLAGS;
+ bip->app_tag = bip_src->app_tag;

return 0;
}
diff --git a/block/fops.c b/block/fops.c
index 13a67940d040..6d5c4fc5a216 100644
--- a/block/fops.c
+++ b/block/fops.c
@@ -54,6 +54,7 @@ static ssize_t __blkdev_direct_IO_simple(struct kiocb *iocb,
struct bio bio;
ssize_t ret;

+ WARN_ON_ONCE(iocb->ki_flags & IOCB_HAS_METADATA);
if (nr_pages <= DIO_INLINE_BIO_VECS)
vecs = inline_vecs;
else {
@@ -124,12 +125,16 @@ static void blkdev_bio_end_io(struct bio *bio)
{
struct blkdev_dio *dio = bio->bi_private;
bool should_dirty = dio->flags & DIO_SHOULD_DIRTY;
+ bool is_sync = dio->flags & DIO_IS_SYNC;

if (bio->bi_status && !dio->bio.bi_status)
dio->bio.bi_status = bio->bi_status;

+ if (!is_sync && (dio->iocb->ki_flags & IOCB_HAS_METADATA))
+ bio_integrity_unmap_user(bio);
+
if (atomic_dec_and_test(&dio->ref)) {
- if (!(dio->flags & DIO_IS_SYNC)) {
+ if (!is_sync) {
struct kiocb *iocb = dio->iocb;
ssize_t ret;

@@ -221,14 +226,16 @@ static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
* a retry of this from blocking context.
*/
if (unlikely(iov_iter_count(iter))) {
- bio_release_pages(bio, false);
- bio_clear_flag(bio, BIO_REFFED);
- bio_put(bio);
- blk_finish_plug(&plug);
- return -EAGAIN;
+ ret = -EAGAIN;
+ goto fail;
}
bio->bi_opf |= REQ_NOWAIT;
}
+ if (!is_sync && (iocb->ki_flags & IOCB_HAS_METADATA)) {
+ ret = bio_integrity_map_iter(bio, iocb->private);
+ if (unlikely(ret))
+ goto fail;
+ }

if (is_read) {
if (dio->flags & DIO_SHOULD_DIRTY)
@@ -269,6 +276,12 @@ static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter,

bio_put(&dio->bio);
return ret;
+fail:
+ bio_release_pages(bio, false);
+ bio_clear_flag(bio, BIO_REFFED);
+ bio_put(bio);
+ blk_finish_plug(&plug);
+ return ret;
}

static void blkdev_bio_end_io_async(struct bio *bio)
@@ -286,6 +299,9 @@ static void blkdev_bio_end_io_async(struct bio *bio)
ret = blk_status_to_errno(bio->bi_status);
}

+ if (iocb->ki_flags & IOCB_HAS_METADATA)
+ bio_integrity_unmap_user(bio);
+
iocb->ki_complete(iocb, ret);

if (dio->flags & DIO_SHOULD_DIRTY) {
@@ -330,10 +346,8 @@ static ssize_t __blkdev_direct_IO_async(struct kiocb *iocb,
bio_iov_bvec_set(bio, iter);
} else {
ret = bio_iov_iter_get_pages(bio, iter);
- if (unlikely(ret)) {
- bio_put(bio);
- return ret;
- }
+ if (unlikely(ret))
+ goto out_bio_put;
}
dio->size = bio->bi_iter.bi_size;

@@ -346,6 +360,13 @@ static ssize_t __blkdev_direct_IO_async(struct kiocb *iocb,
task_io_account_write(bio->bi_iter.bi_size);
}

+ if (iocb->ki_flags & IOCB_HAS_METADATA) {
+ ret = bio_integrity_map_iter(bio, iocb->private);
+ WRITE_ONCE(iocb->private, NULL);
+ if (unlikely(ret))
+ goto out_bio_put;
+ }
+
if (iocb->ki_flags & IOCB_ATOMIC)
bio->bi_opf |= REQ_ATOMIC;

@@ -360,6 +381,10 @@ static ssize_t __blkdev_direct_IO_async(struct kiocb *iocb,
submit_bio(bio);
}
return -EIOCBQUEUED;
+
+out_bio_put:
+ bio_put(bio);
+ return ret;
}

static ssize_t blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
diff --git a/include/linux/bio-integrity.h b/include/linux/bio-integrity.h
index 2195bc06dcde..de0a6c9de4d1 100644
--- a/include/linux/bio-integrity.h
+++ b/include/linux/bio-integrity.h
@@ -23,6 +23,7 @@ struct bio_integrity_payload {
unsigned short bip_vcnt; /* # of integrity bio_vecs */
unsigned short bip_max_vcnt; /* integrity bio_vec slots */
unsigned short bip_flags; /* control flags */
+ u16 app_tag; /* application tag value */

struct bvec_iter bio_iter; /* for rewinding parent bio */

@@ -78,6 +79,7 @@ struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio, gfp_t gfp,
int bio_integrity_add_page(struct bio *bio, struct page *page, unsigned int len,
unsigned int offset);
int bio_integrity_map_user(struct bio *bio, struct iov_iter *iter);
+int bio_integrity_map_iter(struct bio *bio, struct uio_meta *meta);
void bio_integrity_unmap_user(struct bio *bio);
bool bio_integrity_prep(struct bio *bio);
void bio_integrity_advance(struct bio *bio, unsigned int bytes_done);
@@ -108,6 +110,11 @@ static int bio_integrity_map_user(struct bio *bio, struct iov_iter *iter)
return -EINVAL;
}

+static inline int bio_integrity_map_iter(struct bio *bio, struct uio_meta *meta)
+{
+ return -EINVAL;
+}
+
static inline void bio_integrity_unmap_user(struct bio *bio)
{
}
--
2.25.1