[PATCH v5 12/15] dm-verity: make verity_hash() take dm_verity_io instead of ahash_request

Eric Biggers
2024-06-11T03:49:15Z

In preparation for adding shash support to dm-verity, change
verity_hash() to take a pointer to a struct dm_verity_io instead of a
pointer to the ahash_request embedded inside it.

Signed-off-by: Eric Biggers <ebiggers@google.com>
---
drivers/md/dm-verity-fec.c | 6 ++----
drivers/md/dm-verity-target.c | 21 ++++++++++-----------
drivers/md/dm-verity.h | 2 +-
3 files changed, 13 insertions(+), 16 deletions(-)

diff --git a/drivers/md/dm-verity-fec.c b/drivers/md/dm-verity-fec.c
index b838d21183b5..62b1a44b8dd2 100644
--- a/drivers/md/dm-verity-fec.c
+++ b/drivers/md/dm-verity-fec.c
@@ -184,12 +184,11 @@ static int fec_decode_bufs(struct dm_verity *v, struct dm_verity_io *io,
* Locate data block erasures using verity hashes.
*/
static int fec_is_erasure(struct dm_verity *v, struct dm_verity_io *io,
u8 *want_digest, u8 *data)
{
- if (unlikely(verity_hash(v, verity_io_hash_req(v, io),
- data, 1 << v->data_dev_block_bits,
+ if (unlikely(verity_hash(v, io, data, 1 << v->data_dev_block_bits,
verity_io_real_digest(v, io), true)))
return 0;

return memcmp(verity_io_real_digest(v, io), want_digest,
v->digest_size) != 0;
@@ -386,12 +385,11 @@ static int fec_decode_rsb(struct dm_verity *v, struct dm_verity_io *io,

pos += fio->nbufs << DM_VERITY_FEC_BUF_RS_BITS;
}

/* Always re-validate the corrected block against the expected hash */
- r = verity_hash(v, verity_io_hash_req(v, io), fio->output,
- 1 << v->data_dev_block_bits,
+ r = verity_hash(v, io, fio->output, 1 << v->data_dev_block_bits,
verity_io_real_digest(v, io), true);
if (unlikely(r < 0))
return r;

if (memcmp(verity_io_real_digest(v, io), verity_io_want_digest(v, io),
diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c
index 3e2e4f41714c..4aa140751166 100644
--- a/drivers/md/dm-verity-target.c
+++ b/drivers/md/dm-verity-target.c
@@ -178,13 +178,14 @@ static int verity_hash_final(struct dm_verity *v, struct ahash_request *req,
r = crypto_wait_req(crypto_ahash_final(req), wait);
out:
return r;
}

-int verity_hash(struct dm_verity *v, struct ahash_request *req,
+int verity_hash(struct dm_verity *v, struct dm_verity_io *io,
const u8 *data, size_t len, u8 *digest, bool may_sleep)
{
+ struct ahash_request *req = verity_io_hash_req(v, io);
int r;
struct crypto_wait wait;

r = verity_hash_init(v, req, &wait, may_sleep);
if (unlikely(r < 0))
@@ -323,12 +324,11 @@ static int verity_verify_level(struct dm_verity *v, struct dm_verity_io *io,
if (skip_unverified) {
r = 1;
goto release_ret_r;
}

- r = verity_hash(v, verity_io_hash_req(v, io),
- data, 1 << v->hash_dev_block_bits,
+ r = verity_hash(v, io, data, 1 << v->hash_dev_block_bits,
verity_io_real_digest(v, io), !io->in_bh);
if (unlikely(r < 0))
goto release_ret_r;

if (likely(memcmp(verity_io_real_digest(v, io), want_digest,
@@ -426,12 +426,11 @@ static noinline int verity_recheck(struct dm_verity *v, struct dm_verity_io *io,
io_loc.count = 1 << (v->data_dev_block_bits - SECTOR_SHIFT);
r = dm_io(&io_req, 1, &io_loc, NULL, IOPRIO_DEFAULT);
if (unlikely(r))
goto free_ret;

- r = verity_hash(v, verity_io_hash_req(v, io), buffer,
- 1 << v->data_dev_block_bits,
+ r = verity_hash(v, io, buffer, 1 << v->data_dev_block_bits,
verity_io_real_digest(v, io), true);
if (unlikely(r))
goto free_ret;

if (memcmp(verity_io_real_digest(v, io),
@@ -542,11 +541,11 @@ static int verity_verify_io(struct dm_verity_io *io)
memset(data, 0, block_size);
kunmap_local(data);
continue;
}

- r = verity_hash(v, verity_io_hash_req(v, io), data, block_size,
+ r = verity_hash(v, io, data, block_size,
verity_io_real_digest(v, io), !io->in_bh);
if (unlikely(r < 0)) {
kunmap_local(data);
return r;
}
@@ -983,33 +982,33 @@ static int verity_alloc_most_once(struct dm_verity *v)
}

static int verity_alloc_zero_digest(struct dm_verity *v)
{
int r = -ENOMEM;
- struct ahash_request *req;
+ struct dm_verity_io *io;
u8 *zero_data;

v->zero_digest = kmalloc(v->digest_size, GFP_KERNEL);

if (!v->zero_digest)
return r;

- req = kmalloc(v->ahash_reqsize, GFP_KERNEL);
+ io = kmalloc(sizeof(*io) + v->ahash_reqsize, GFP_KERNEL);

- if (!req)
+ if (!io)
return r; /* verity_dtr will free zero_digest */

zero_data = kzalloc(1 << v->data_dev_block_bits, GFP_KERNEL);

if (!zero_data)
goto out;

- r = verity_hash(v, req, zero_data, 1 << v->data_dev_block_bits,
+ r = verity_hash(v, io, zero_data, 1 << v->data_dev_block_bits,
v->zero_digest, true);

out:
- kfree(req);
+ kfree(io);
kfree(zero_data);

return r;
}

diff --git a/drivers/md/dm-verity.h b/drivers/md/dm-verity.h
index bd461c28b710..0e1dd02a916f 100644
--- a/drivers/md/dm-verity.h
+++ b/drivers/md/dm-verity.h
@@ -114,11 +114,11 @@ static inline u8 *verity_io_want_digest(struct dm_verity *v,
struct dm_verity_io *io)
{
return io->want_digest;
}

-extern int verity_hash(struct dm_verity *v, struct ahash_request *req,
+extern int verity_hash(struct dm_verity *v, struct dm_verity_io *io,
const u8 *data, size_t len, u8 *digest, bool may_sleep);

extern int verity_hash_for_block(struct dm_verity *v, struct dm_verity_io *io,
sector_t block, u8 *digest, bool *is_zero);

--
2.45.1