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| author | Eric Biggers <ebiggers@google.com> | 2022-12-23 12:36:30 -0800 |
|---|---|---|
| committer | Eric Biggers <ebiggers@google.com> | 2023-01-09 19:05:56 -0800 |
| commit | 579a12f78d889339488175cd9f353dba2bb8d047 (patch) | |
| tree | b5ab4ec28788a73a4be44534f080f2889bac9a06 /fs/verity | |
| parent | 9098f36b739db9a77d24b7c302dcb9d3fe987308 (diff) | |
| download | lwn-579a12f78d889339488175cd9f353dba2bb8d047.tar.gz lwn-579a12f78d889339488175cd9f353dba2bb8d047.zip | |
fsverity: store log2(digest_size) precomputed
Add log_digestsize to struct merkle_tree_params so that it can be used
in verify.c. Also save memory by using u8 for all the log_* fields.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Andrey Albershteyn <aalbersh@redhat.com>
Tested-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://lore.kernel.org/r/20221223203638.41293-4-ebiggers@kernel.org
Diffstat (limited to 'fs/verity')
| -rw-r--r-- | fs/verity/fsverity_private.h | 5 | ||||
| -rw-r--r-- | fs/verity/open.c | 3 | ||||
| -rw-r--r-- | fs/verity/verify.c | 2 |
3 files changed, 6 insertions, 4 deletions
diff --git a/fs/verity/fsverity_private.h b/fs/verity/fsverity_private.h index 48b97f5d0556..fc1c2797fab1 100644 --- a/fs/verity/fsverity_private.h +++ b/fs/verity/fsverity_private.h @@ -42,8 +42,9 @@ struct merkle_tree_params { unsigned int digest_size; /* same as hash_alg->digest_size */ unsigned int block_size; /* size of data and tree blocks */ unsigned int hashes_per_block; /* number of hashes per tree block */ - unsigned int log_blocksize; /* log2(block_size) */ - unsigned int log_arity; /* log2(hashes_per_block) */ + u8 log_digestsize; /* log2(digest_size) */ + u8 log_blocksize; /* log2(block_size) */ + u8 log_arity; /* log2(hashes_per_block) */ unsigned int num_levels; /* number of levels in Merkle tree */ u64 tree_size; /* Merkle tree size in bytes */ unsigned long tree_pages; /* Merkle tree size in pages */ diff --git a/fs/verity/open.c b/fs/verity/open.c index e356eefb54d7..ca8de73e5a0b 100644 --- a/fs/verity/open.c +++ b/fs/verity/open.c @@ -76,7 +76,8 @@ int fsverity_init_merkle_tree_params(struct merkle_tree_params *params, err = -EINVAL; goto out_err; } - params->log_arity = params->log_blocksize - ilog2(params->digest_size); + params->log_digestsize = ilog2(params->digest_size); + params->log_arity = log_blocksize - params->log_digestsize; params->hashes_per_block = 1 << params->log_arity; /* diff --git a/fs/verity/verify.c b/fs/verity/verify.c index 4c57a1bd01af..d2fcb6a21ea8 100644 --- a/fs/verity/verify.c +++ b/fs/verity/verify.c @@ -35,7 +35,7 @@ static void hash_at_level(const struct merkle_tree_params *params, /* Offset of the wanted hash (in bytes) within the hash block */ *hoffset = (position & ((1 << params->log_arity) - 1)) << - (params->log_blocksize - params->log_arity); + params->log_digestsize; } static inline int cmp_hashes(const struct fsverity_info *vi, |