lkml.org 
[lkml]   [2011]   [Nov]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH] dm: verity target
From
On Thu, Nov 10, 2011 at 1:44 AM, Steffen Klassert
<steffen.klassert@secunet.com> wrote:
> On Wed, Nov 09, 2011 at 09:18:10PM -0800, Mandeep Singh Baines wrote:
>>
>> + * TODO(wad): All hash storage memory is pre-allocated and freed once an
>> + * entire branch has been verified.
>> + */
>> +struct dm_bht {
>> +     /* Configured values */
>> +     int depth;  /* Depth of the tree including the root */
>> +     unsigned int block_count;  /* Number of blocks hashed */
>> +     unsigned int block_size;  /* Size of a hash block */
>> +     char hash_alg[CRYPTO_MAX_ALG_NAME];
>> +     unsigned char salt[DM_BHT_SALT_SIZE];
>> +
>> +     /* Computed values */
>> +     unsigned int node_count;  /* Data size (in hashes) for each entry */
>> +     unsigned int node_count_shift;  /* first bit set - 1 */
>> +     /* There is one per CPU so that verified can be simultaneous. */
>> +     struct hash_desc hash_desc[NR_CPUS];  /* Container for the hash alg */
>
> Please don't add a new user for the old hash interface. If the hashes can
> be done asynchronous you can use ahash, if not use shash. Both interfaces
> are reentrant, that's probaply what you want to have here. You don't
> need to have this in a per cpu manner.

I'll check out the two interfaces. I didn't realize hash_desc was
deprecated specifically in favor of one of the others. I'm interested
in seeing if it is possible to not keep a per-cpu desc though with the
other apis. We do this now to avoid contention across multiple kernel
threads on crypto operations sharing the hash_desc (e.g., by wrapping
it in a mutex).

Thanks!
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2011-11-10 15:45    [W:0.043 / U:4.876 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site