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crypto: nx - Avoid -Wflex-array-member-not-at-end warning

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-Wflex-array-member-not-at-end is coming in GCC-14, and we are getting
ready to enable it globally. So, we are deprecating flexible-array
members in the middle of another structure.

There is currently an object (`header`) in `struct nx842_crypto_ctx`
that contains a flexible structure (`struct nx842_crypto_header`):

struct nx842_crypto_ctx {
	...
        struct nx842_crypto_header header;
        struct nx842_crypto_header_group group[NX842_CRYPTO_GROUP_MAX];
	...
};

So, in order to avoid ending up with a flexible-array member in the
middle of another struct, we use the `struct_group_tagged()` helper to
separate the flexible array from the rest of the members in the flexible
structure:

struct nx842_crypto_header {
	struct_group_tagged(nx842_crypto_header_hdr, hdr,

		... the rest of the members

	);
        struct nx842_crypto_header_group group[];
} __packed;

With the change described above, we can now declare an object of the
type of the tagged struct, without embedding the flexible array in the
middle of another struct:

struct nx842_crypto_ctx {
	...
        struct nx842_crypto_header_hdr header;
        struct nx842_crypto_header_group group[NX842_CRYPTO_GROUP_MAX];
	...
 } __packed;

We also use `container_of()` whenever we need to retrieve a pointer to
the flexible structure, through which we can access the flexible
array if needed.

So, with these changes, fix the following warning:

In file included from drivers/crypto/nx/nx-842.c:55:
drivers/crypto/nx/nx-842.h:174:36: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]
  174 |         struct nx842_crypto_header header;
      |                                    ^~~~~~

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Gustavo A. R. Silva 2024-03-05 13:57:56 -06:00 committed by Herbert Xu
parent 7467147ef9
commit 1e6b251ce1
2 changed files with 10 additions and 6 deletions
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6
drivers/crypto/nx/nx-842.c
View File

@ -251,7 +251,9 @@ int nx842_crypto_compress(struct crypto_tfm *tfm,
u8 *dst, unsigned int *dlen)
{
struct nx842_crypto_ctx *ctx = crypto_tfm_ctx(tfm);
struct nx842_crypto_header *hdr = &ctx->header;
struct nx842_crypto_header *hdr =
container_of(&ctx->header,
struct nx842_crypto_header, hdr);
struct nx842_crypto_param p;
struct nx842_constraints c = *ctx->driver->constraints;
unsigned int groups, hdrsize, h;
@ -490,7 +492,7 @@ int nx842_crypto_decompress(struct crypto_tfm *tfm,
}
memcpy(&ctx->header, src, hdr_len);
hdr = &ctx->header;
hdr = container_of(&ctx->header, struct nx842_crypto_header, hdr);
for (n = 0; n < hdr->groups; n++) {
/* ignore applies to last group */

10
drivers/crypto/nx/nx-842.h
View File

@ -157,9 +157,11 @@ struct nx842_crypto_header_group {
} __packed;
struct nx842_crypto_header {
__be16 magic; /* NX842_CRYPTO_MAGIC */
__be16 ignore; /* decompressed end bytes to ignore */
u8 groups; /* total groups in this header */
struct_group_tagged(nx842_crypto_header_hdr, hdr,
__be16 magic; /* NX842_CRYPTO_MAGIC */
__be16 ignore; /* decompressed end bytes to ignore */
u8 groups; /* total groups in this header */
);
struct nx842_crypto_header_group group[];
} __packed;
@ -171,7 +173,7 @@ struct nx842_crypto_ctx {
u8 *wmem;
u8 *sbounce, *dbounce;
struct nx842_crypto_header header;
struct nx842_crypto_header_hdr header;
struct nx842_crypto_header_group group[NX842_CRYPTO_GROUP_MAX];
struct nx842_driver *driver;