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-rw-r--r--block/bio-integrity.c218
1 files changed, 216 insertions, 2 deletions
diff --git a/block/bio-integrity.c b/block/bio-integrity.c
index ec8ac8cf6e1b..feef615e2c9c 100644
--- a/block/bio-integrity.c
+++ b/block/bio-integrity.c
@@ -69,15 +69,15 @@ struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio,
memset(bip, 0, sizeof(*bip));
+ /* always report as many vecs as asked explicitly, not inline vecs */
+ bip->bip_max_vcnt = nr_vecs;
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;
@@ -91,6 +91,47 @@ err:
}
EXPORT_SYMBOL(bio_integrity_alloc);
+static void bio_integrity_unpin_bvec(struct bio_vec *bv, int nr_vecs,
+ bool dirty)
+{
+ int i;
+
+ for (i = 0; i < nr_vecs; i++) {
+ if (dirty && !PageCompound(bv[i].bv_page))
+ set_page_dirty_lock(bv[i].bv_page);
+ unpin_user_page(bv[i].bv_page);
+ }
+}
+
+static void bio_integrity_uncopy_user(struct bio_integrity_payload *bip)
+{
+ unsigned short nr_vecs = bip->bip_max_vcnt - 1;
+ struct bio_vec *copy = &bip->bip_vec[1];
+ size_t bytes = bip->bip_iter.bi_size;
+ struct iov_iter iter;
+ int ret;
+
+ iov_iter_bvec(&iter, ITER_DEST, copy, nr_vecs, bytes);
+ ret = copy_to_iter(bvec_virt(bip->bip_vec), bytes, &iter);
+ WARN_ON_ONCE(ret != bytes);
+
+ bio_integrity_unpin_bvec(copy, nr_vecs, true);
+}
+
+static void bio_integrity_unmap_user(struct bio_integrity_payload *bip)
+{
+ bool dirty = bio_data_dir(bip->bip_bio) == READ;
+
+ if (bip->bip_flags & BIP_COPY_USER) {
+ if (dirty)
+ bio_integrity_uncopy_user(bip);
+ kfree(bvec_virt(bip->bip_vec));
+ return;
+ }
+
+ 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
@@ -105,6 +146,8 @@ void bio_integrity_free(struct bio *bio)
if (bip->bip_flags & BIP_BLOCK_INTEGRITY)
kfree(bvec_virt(bip->bip_vec));
+ else if (bip->bip_flags & BIP_INTEGRITY_USER)
+ bio_integrity_unmap_user(bip);
__bio_integrity_free(bs, bip);
bio->bi_integrity = NULL;
@@ -160,6 +203,177 @@ int bio_integrity_add_page(struct bio *bio, struct page *page,
}
EXPORT_SYMBOL(bio_integrity_add_page);
+static int bio_integrity_copy_user(struct bio *bio, struct bio_vec *bvec,
+ int nr_vecs, unsigned int len,
+ unsigned int direction, u32 seed)
+{
+ bool write = direction == ITER_SOURCE;
+ struct bio_integrity_payload *bip;
+ struct iov_iter iter;
+ void *buf;
+ int ret;
+
+ buf = kmalloc(len, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ if (write) {
+ iov_iter_bvec(&iter, direction, bvec, nr_vecs, len);
+ if (!copy_from_iter_full(buf, len, &iter)) {
+ ret = -EFAULT;
+ goto free_buf;
+ }
+
+ bip = bio_integrity_alloc(bio, GFP_KERNEL, 1);
+ } else {
+ memset(buf, 0, len);
+
+ /*
+ * We need to preserve the original bvec and the number of vecs
+ * in it for completion handling
+ */
+ bip = bio_integrity_alloc(bio, GFP_KERNEL, nr_vecs + 1);
+ }
+
+ if (IS_ERR(bip)) {
+ ret = PTR_ERR(bip);
+ goto free_buf;
+ }
+
+ if (write)
+ bio_integrity_unpin_bvec(bvec, nr_vecs, false);
+ else
+ memcpy(&bip->bip_vec[1], bvec, nr_vecs * sizeof(*bvec));
+
+ ret = bio_integrity_add_page(bio, virt_to_page(buf), len,
+ offset_in_page(buf));
+ if (ret != len) {
+ ret = -ENOMEM;
+ goto free_bip;
+ }
+
+ bip->bip_flags |= BIP_INTEGRITY_USER | BIP_COPY_USER;
+ bip->bip_iter.bi_sector = seed;
+ return 0;
+free_bip:
+ bio_integrity_free(bio);
+free_buf:
+ kfree(buf);
+ return ret;
+}
+
+static int bio_integrity_init_user(struct bio *bio, struct bio_vec *bvec,
+ int nr_vecs, unsigned int len, u32 seed)
+{
+ struct bio_integrity_payload *bip;
+
+ bip = bio_integrity_alloc(bio, GFP_KERNEL, nr_vecs);
+ if (IS_ERR(bip))
+ 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;
+ return 0;
+}
+
+static unsigned int bvec_from_pages(struct bio_vec *bvec, struct page **pages,
+ int nr_vecs, ssize_t bytes, ssize_t offset)
+{
+ unsigned int nr_bvecs = 0;
+ int i, j;
+
+ for (i = 0; i < nr_vecs; i = j) {
+ size_t size = min_t(size_t, bytes, PAGE_SIZE - offset);
+ struct folio *folio = page_folio(pages[i]);
+
+ bytes -= size;
+ for (j = i + 1; j < nr_vecs; j++) {
+ size_t next = min_t(size_t, PAGE_SIZE, bytes);
+
+ if (page_folio(pages[j]) != folio ||
+ pages[j] != pages[j - 1] + 1)
+ break;
+ unpin_user_page(pages[j]);
+ size += next;
+ bytes -= next;
+ }
+
+ bvec_set_page(&bvec[nr_bvecs], pages[i], size, offset);
+ offset = 0;
+ nr_bvecs++;
+ }
+
+ return nr_bvecs;
+}
+
+int bio_integrity_map_user(struct bio *bio, void __user *ubuf, ssize_t bytes,
+ u32 seed)
+{
+ struct request_queue *q = bdev_get_queue(bio->bi_bdev);
+ unsigned int align = q->dma_pad_mask | queue_dma_alignment(q);
+ struct page *stack_pages[UIO_FASTIOV], **pages = stack_pages;
+ struct bio_vec stack_vec[UIO_FASTIOV], *bvec = stack_vec;
+ unsigned int direction, nr_bvecs;
+ struct iov_iter iter;
+ int ret, nr_vecs;
+ size_t offset;
+ bool copy;
+
+ if (bio_integrity(bio))
+ return -EINVAL;
+ if (bytes >> SECTOR_SHIFT > queue_max_hw_sectors(q))
+ return -E2BIG;
+
+ if (bio_data_dir(bio) == READ)
+ direction = ITER_DEST;
+ else
+ direction = ITER_SOURCE;
+
+ iov_iter_ubuf(&iter, direction, ubuf, bytes);
+ nr_vecs = iov_iter_npages(&iter, BIO_MAX_VECS + 1);
+ if (nr_vecs > BIO_MAX_VECS)
+ return -E2BIG;
+ if (nr_vecs > UIO_FASTIOV) {
+ bvec = kcalloc(sizeof(*bvec), nr_vecs, GFP_KERNEL);
+ if (!bvec)
+ return -ENOMEM;
+ pages = NULL;
+ }
+
+ copy = !iov_iter_is_aligned(&iter, align, align);
+ ret = iov_iter_extract_pages(&iter, &pages, bytes, nr_vecs, 0, &offset);
+ if (unlikely(ret < 0))
+ goto free_bvec;
+
+ nr_bvecs = bvec_from_pages(bvec, pages, nr_vecs, bytes, offset);
+ if (pages != stack_pages)
+ kvfree(pages);
+ if (nr_bvecs > queue_max_integrity_segments(q))
+ copy = true;
+
+ if (copy)
+ ret = bio_integrity_copy_user(bio, bvec, nr_bvecs, bytes,
+ direction, seed);
+ else
+ ret = bio_integrity_init_user(bio, bvec, nr_bvecs, bytes, seed);
+ if (ret)
+ goto release_pages;
+ if (bvec != stack_vec)
+ kfree(bvec);
+
+ return 0;
+
+release_pages:
+ bio_integrity_unpin_bvec(bvec, nr_bvecs, false);
+free_bvec:
+ if (bvec != stack_vec)
+ kfree(bvec);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(bio_integrity_map_user);
+
/**
* bio_integrity_process - Process integrity metadata for a bio
* @bio: bio to generate/verify integrity metadata for