ceph: buffer decoding helpers
Helper for decoding into a ceph_buffer, and other misc decoding helpers
we will need.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/buffer.c b/fs/ceph/buffer.c
index 2576bd4..b98086c 100644
--- a/fs/ceph/buffer.c
+++ b/fs/ceph/buffer.c
@@ -1,6 +1,7 @@
#include "ceph_debug.h"
#include "buffer.h"
+#include "decode.h"
struct ceph_buffer *ceph_buffer_new(size_t len, gfp_t gfp)
{
@@ -59,3 +60,19 @@
return 0;
}
+int ceph_decode_buffer(struct ceph_buffer **b, void **p, void *end)
+{
+ size_t len;
+
+ ceph_decode_need(p, end, sizeof(u32), bad);
+ len = ceph_decode_32(p);
+ dout("decode_buffer len %d\n", (int)len);
+ ceph_decode_need(p, end, len, bad);
+ *b = ceph_buffer_new(len, GFP_NOFS);
+ if (!*b)
+ return -ENOMEM;
+ ceph_decode_copy(p, (*b)->vec.iov_base, len);
+ return 0;
+bad:
+ return -EINVAL;
+}
diff --git a/fs/ceph/buffer.h b/fs/ceph/buffer.h
index 47b9514..58d1901 100644
--- a/fs/ceph/buffer.h
+++ b/fs/ceph/buffer.h
@@ -34,4 +34,6 @@
kref_put(&b->kref, ceph_buffer_release);
}
+extern int ceph_decode_buffer(struct ceph_buffer **b, void **p, void *end);
+
#endif
diff --git a/fs/ceph/decode.h b/fs/ceph/decode.h
index b90a33b..65b3e02 100644
--- a/fs/ceph/decode.h
+++ b/fs/ceph/decode.h
@@ -2,6 +2,7 @@
#define __CEPH_DECODE_H
#include <asm/unaligned.h>
+#include <linux/time.h>
#include "types.h"
@@ -65,6 +66,11 @@
ceph_decode_need(p, end, sizeof(u16), bad); \
v = ceph_decode_16(p); \
} while (0)
+#define ceph_decode_8_safe(p, end, v, bad) \
+ do { \
+ ceph_decode_need(p, end, sizeof(u8), bad); \
+ v = ceph_decode_8(p); \
+ } while (0)
#define ceph_decode_copy_safe(p, end, pv, n, bad) \
do { \
@@ -156,5 +162,33 @@
*p += len;
}
+#define ceph_encode_need(p, end, n, bad) \
+ do { \
+ if (unlikely(*(p) + (n) > (end))) \
+ goto bad; \
+ } while (0)
+
+#define ceph_encode_64_safe(p, end, v, bad) \
+ do { \
+ ceph_encode_need(p, end, sizeof(u64), bad); \
+ ceph_encode_64(p, v); \
+ } while (0)
+#define ceph_encode_32_safe(p, end, v, bad) \
+ do { \
+ ceph_encode_need(p, end, sizeof(u32), bad); \
+ ceph_encode_32(p, v); \
+ } while (0)
+#define ceph_encode_16_safe(p, end, v, bad) \
+ do { \
+ ceph_encode_need(p, end, sizeof(u16), bad); \
+ ceph_encode_16(p, v); \
+ } while (0)
+
+#define ceph_encode_copy_safe(p, end, pv, n, bad) \
+ do { \
+ ceph_encode_need(p, end, n, bad); \
+ ceph_encode_copy(p, pv, n); \
+ } while (0)
+
#endif