diff options
Diffstat (limited to 'include/linux/crypto.h')
| -rw-r--r-- | include/linux/crypto.h | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/include/linux/crypto.h b/include/linux/crypto.h index 9b55cd6b1f1b..da5e0d74bb2f 100644 --- a/include/linux/crypto.h +++ b/include/linux/crypto.h @@ -151,9 +151,12 @@ * The macro CRYPTO_MINALIGN_ATTR (along with the void * type in the actual * declaration) is used to ensure that the crypto_tfm context structure is * aligned correctly for the given architecture so that there are no alignment - * faults for C data types. In particular, this is required on platforms such - * as arm where pointers are 32-bit aligned but there are data types such as - * u64 which require 64-bit alignment. + * faults for C data types. On architectures that support non-cache coherent + * DMA, such as ARM or arm64, it also takes into account the minimal alignment + * that is required to ensure that the context struct member does not share any + * cachelines with the rest of the struct. This is needed to ensure that cache + * maintenance for non-coherent DMA (cache invalidation in particular) does not + * affect data that may be accessed by the CPU concurrently. */ #define CRYPTO_MINALIGN ARCH_KMALLOC_MINALIGN |