libceph: ceph_decode_skip_* helpers

Some of these won't be as efficient as they could be (e.g.
ceph_decode_skip_set(... 32 ...) could advance by len * sizeof(u32)
once instead of advancing by sizeof(u32) len times), but that's fine
and not worth a bunch of extra macro code.

Replace skip_name_map() with ceph_decode_skip_map as an example.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
This commit is contained in:
Ilya Dryomov 2017-06-21 17:27:17 +02:00
parent ab75144be0
commit 278b1d709c
2 changed files with 63 additions and 22 deletions

View File

@ -132,6 +132,66 @@ bad:
return ERR_PTR(-ERANGE);
}
/*
* skip helpers
*/
#define ceph_decode_skip_n(p, end, n, bad) \
do { \
ceph_decode_need(p, end, n, bad); \
*p += n; \
} while (0)
#define ceph_decode_skip_64(p, end, bad) \
ceph_decode_skip_n(p, end, sizeof(u64), bad)
#define ceph_decode_skip_32(p, end, bad) \
ceph_decode_skip_n(p, end, sizeof(u32), bad)
#define ceph_decode_skip_16(p, end, bad) \
ceph_decode_skip_n(p, end, sizeof(u16), bad)
#define ceph_decode_skip_8(p, end, bad) \
ceph_decode_skip_n(p, end, sizeof(u8), bad)
#define ceph_decode_skip_string(p, end, bad) \
do { \
u32 len; \
\
ceph_decode_32_safe(p, end, len, bad); \
ceph_decode_skip_n(p, end, len, bad); \
} while (0)
#define ceph_decode_skip_set(p, end, type, bad) \
do { \
u32 len; \
\
ceph_decode_32_safe(p, end, len, bad); \
while (len--) \
ceph_decode_skip_##type(p, end, bad); \
} while (0)
#define ceph_decode_skip_map(p, end, ktype, vtype, bad) \
do { \
u32 len; \
\
ceph_decode_32_safe(p, end, len, bad); \
while (len--) { \
ceph_decode_skip_##ktype(p, end, bad); \
ceph_decode_skip_##vtype(p, end, bad); \
} \
} while (0)
#define ceph_decode_skip_map_of_map(p, end, ktype1, ktype2, vtype2, bad) \
do { \
u32 len; \
\
ceph_decode_32_safe(p, end, len, bad); \
while (len--) { \
ceph_decode_skip_##ktype1(p, end, bad); \
ceph_decode_skip_map(p, end, ktype2, vtype2, bad); \
} \
} while (0)
/*
* struct ceph_timespec <-> struct timespec
*/

View File

@ -138,21 +138,6 @@ bad:
return -EINVAL;
}
static int skip_name_map(void **p, void *end)
{
int len;
ceph_decode_32_safe(p, end, len ,bad);
while (len--) {
int strlen;
*p += sizeof(u32);
ceph_decode_32_safe(p, end, strlen, bad);
*p += strlen;
}
return 0;
bad:
return -EINVAL;
}
static void crush_finalize(struct crush_map *c)
{
__s32 b;
@ -187,7 +172,6 @@ static struct crush_map *crush_decode(void *pbyval, void *end)
void **p = &pbyval;
void *start = pbyval;
u32 magic;
u32 num_name_maps;
dout("crush_decode %p to %p len %d\n", *p, end, (int)(end - *p));
@ -353,12 +337,9 @@ static struct crush_map *crush_decode(void *pbyval, void *end)
}
}
/* ignore trailing name maps. */
for (num_name_maps = 0; num_name_maps < 3; num_name_maps++) {
err = skip_name_map(p, end);
if (err < 0)
goto done;
}
ceph_decode_skip_map(p, end, 32, string, bad); /* type_map */
ceph_decode_skip_map(p, end, 32, string, bad); /* name_map */
ceph_decode_skip_map(p, end, 32, string, bad); /* rule_name_map */
/* tunables */
ceph_decode_need(p, end, 3*sizeof(u32), done);