1 files changed, 194 insertions, 0 deletions

diff --git a/fs/ceph/decode.h b/fs/ceph/decode.h
new file mode 100644
index 000000000000..65b3e022eaf5
--- /dev/null
+++ b/fs/ceph/decode.h
@@ -0,0 +1,194 @@
+#ifndef __CEPH_DECODE_H
+#define __CEPH_DECODE_H
+
+#include <asm/unaligned.h>
+#include <linux/time.h>
+
+#include "types.h"
+
+/*
+ * in all cases,
+ *   void **p     pointer to position pointer
+ *   void *end    pointer to end of buffer (last byte + 1)
+ */
+
+static inline u64 ceph_decode_64(void **p)
+{
+        u64 v = get_unaligned_le64(*p);
+        *p += sizeof(u64);
+        return v;
+}
+static inline u32 ceph_decode_32(void **p)
+{
+        u32 v = get_unaligned_le32(*p);
+        *p += sizeof(u32);
+        return v;
+}
+static inline u16 ceph_decode_16(void **p)
+{
+        u16 v = get_unaligned_le16(*p);
+        *p += sizeof(u16);
+        return v;
+}
+static inline u8 ceph_decode_8(void **p)
+{
+        u8 v = *(u8 *)*p;
+        (*p)++;
+        return v;
+}
+static inline void ceph_decode_copy(void **p, void *pv, size_t n)
+{
+        memcpy(pv, *p, n);
+        *p += n;
+}
+
+/*
+ * bounds check input.
+ */
+#define ceph_decode_need(p, end, n, bad)                \
+        do {                                            \
+                if (unlikely(*(p) + (n) > (end)))       \
+                        goto bad;                       \
+        } while (0)
+
+#define ceph_decode_64_safe(p, end, v, bad)                     \
+        do {                                                    \
+                ceph_decode_need(p, end, sizeof(u64), bad);     \
+                v = ceph_decode_64(p);                          \
+        } while (0)
+#define ceph_decode_32_safe(p, end, v, bad)                     \
+        do {                                                    \
+                ceph_decode_need(p, end, sizeof(u32), bad);     \
+                v = ceph_decode_32(p);                          \
+        } while (0)
+#define ceph_decode_16_safe(p, end, v, bad)                     \
+        do {                                                    \
+                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 {                                                    \
+                ceph_decode_need(p, end, n, bad);               \
+                ceph_decode_copy(p, pv, n);                     \
+        } while (0)
+
+/*
+ * struct ceph_timespec <-> struct timespec
+ */
+static inline void ceph_decode_timespec(struct timespec *ts,
+                                        const struct ceph_timespec *tv)
+{
+        ts->tv_sec = le32_to_cpu(tv->tv_sec);
+        ts->tv_nsec = le32_to_cpu(tv->tv_nsec);
+}
+static inline void ceph_encode_timespec(struct ceph_timespec *tv,
+                                        const struct timespec *ts)
+{
+        tv->tv_sec = cpu_to_le32(ts->tv_sec);
+        tv->tv_nsec = cpu_to_le32(ts->tv_nsec);
+}
+
+/*
+ * sockaddr_storage <-> ceph_sockaddr
+ */
+static inline void ceph_encode_addr(struct ceph_entity_addr *a)
+{
+        a->in_addr.ss_family = htons(a->in_addr.ss_family);
+}
+static inline void ceph_decode_addr(struct ceph_entity_addr *a)
+{
+        a->in_addr.ss_family = ntohs(a->in_addr.ss_family);
+        WARN_ON(a->in_addr.ss_family == 512);
+}
+
+/*
+ * encoders
+ */
+static inline void ceph_encode_64(void **p, u64 v)
+{
+        put_unaligned_le64(v, (__le64 *)*p);
+        *p += sizeof(u64);
+}
+static inline void ceph_encode_32(void **p, u32 v)
+{
+        put_unaligned_le32(v, (__le32 *)*p);
+        *p += sizeof(u32);
+}
+static inline void ceph_encode_16(void **p, u16 v)
+{
+        put_unaligned_le16(v, (__le16 *)*p);
+        *p += sizeof(u16);
+}
+static inline void ceph_encode_8(void **p, u8 v)
+{
+        *(u8 *)*p = v;
+        (*p)++;
+}
+static inline void ceph_encode_copy(void **p, const void *s, int len)
+{
+        memcpy(*p, s, len);
+        *p += len;
+}
+
+/*
+ * filepath, string encoders
+ */
+static inline void ceph_encode_filepath(void **p, void *end,
+                                        u64 ino, const char *path)
+{
+        u32 len = path ? strlen(path) : 0;
+        BUG_ON(*p + sizeof(ino) + sizeof(len) + len > end);
+        ceph_encode_8(p, 1);
+        ceph_encode_64(p, ino);
+        ceph_encode_32(p, len);
+        if (len)
+                memcpy(*p, path, len);
+        *p += len;
+}
+
+static inline void ceph_encode_string(void **p, void *end,
+                                      const char *s, u32 len)
+{
+        BUG_ON(*p + sizeof(len) + len > end);
+        ceph_encode_32(p, len);
+        if (len)
+                memcpy(*p, s, len);
+        *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