Commit 0ae060ca authored by Trond Myklebust's avatar Trond Myklebust Committed by Anna Schumaker

SUNRPC: Add generic helpers for xdr_stream encode/decode

Add some generic helpers for encoding/decoding opaque structures and
basic u32/u64.
Signed-off-by: default avatarTrond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: default avatarChuck Lever <chuck.lever@oracle.com>
Signed-off-by: default avatarAnna Schumaker <Anna.Schumaker@Netapp.com>
parent 9761a246
...@@ -242,6 +242,183 @@ extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len); ...@@ -242,6 +242,183 @@ extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len); extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data); extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
/**
* xdr_align_size - Calculate padded size of an object
* @n: Size of an object being XDR encoded (in bytes)
*
* Return value:
* Size (in bytes) of the object including xdr padding
*/
static inline size_t
xdr_align_size(size_t n)
{
const size_t mask = sizeof(__u32) - 1;
return (n + mask) & ~mask;
}
/**
* xdr_stream_encode_u32 - Encode a 32-bit integer
* @xdr: pointer to xdr_stream
* @n: integer to encode
*
* Return values:
* On success, returns length in bytes of XDR buffer consumed
* %-EMSGSIZE on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_encode_u32(struct xdr_stream *xdr, __u32 n)
{
const size_t len = sizeof(n);
__be32 *p = xdr_reserve_space(xdr, len);
if (unlikely(!p))
return -EMSGSIZE;
*p = cpu_to_be32(n);
return len;
}
/**
* xdr_stream_encode_u64 - Encode a 64-bit integer
* @xdr: pointer to xdr_stream
* @n: 64-bit integer to encode
*
* Return values:
* On success, returns length in bytes of XDR buffer consumed
* %-EMSGSIZE on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_encode_u64(struct xdr_stream *xdr, __u64 n)
{
const size_t len = sizeof(n);
__be32 *p = xdr_reserve_space(xdr, len);
if (unlikely(!p))
return -EMSGSIZE;
xdr_encode_hyper(p, n);
return len;
}
/**
* xdr_stream_encode_opaque_fixed - Encode fixed length opaque xdr data
* @xdr: pointer to xdr_stream
* @ptr: pointer to opaque data object
* @len: size of object pointed to by @ptr
*
* Return values:
* On success, returns length in bytes of XDR buffer consumed
* %-EMSGSIZE on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_encode_opaque_fixed(struct xdr_stream *xdr, const void *ptr, size_t len)
{
__be32 *p = xdr_reserve_space(xdr, len);
if (unlikely(!p))
return -EMSGSIZE;
xdr_encode_opaque_fixed(p, ptr, len);
return xdr_align_size(len);
}
/**
* xdr_stream_encode_opaque - Encode variable length opaque xdr data
* @xdr: pointer to xdr_stream
* @ptr: pointer to opaque data object
* @len: size of object pointed to by @ptr
*
* Return values:
* On success, returns length in bytes of XDR buffer consumed
* %-EMSGSIZE on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_encode_opaque(struct xdr_stream *xdr, const void *ptr, size_t len)
{
size_t count = sizeof(__u32) + xdr_align_size(len);
__be32 *p = xdr_reserve_space(xdr, count);
if (unlikely(!p))
return -EMSGSIZE;
xdr_encode_opaque(p, ptr, len);
return count;
}
/**
* xdr_stream_decode_u32 - Decode a 32-bit integer
* @xdr: pointer to xdr_stream
* @ptr: location to store integer
*
* Return values:
* %0 on success
* %-EBADMSG on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_decode_u32(struct xdr_stream *xdr, __u32 *ptr)
{
const size_t count = sizeof(*ptr);
__be32 *p = xdr_inline_decode(xdr, count);
if (unlikely(!p))
return -EBADMSG;
*ptr = be32_to_cpup(p);
return 0;
}
/**
* xdr_stream_decode_opaque_fixed - Decode fixed length opaque xdr data
* @xdr: pointer to xdr_stream
* @ptr: location to store data
* @len: size of buffer pointed to by @ptr
*
* Return values:
* On success, returns size of object stored in @ptr
* %-EBADMSG on XDR buffer overflow
*/
static inline ssize_t
xdr_stream_decode_opaque_fixed(struct xdr_stream *xdr, void *ptr, size_t len)
{
__be32 *p = xdr_inline_decode(xdr, len);
if (unlikely(!p))
return -EBADMSG;
xdr_decode_opaque_fixed(p, ptr, len);
return len;
}
/**
* xdr_stream_decode_opaque_inline - Decode variable length opaque xdr data
* @xdr: pointer to xdr_stream
* @ptr: location to store pointer to opaque data
* @maxlen: maximum acceptable object size
*
* Note: the pointer stored in @ptr cannot be assumed valid after the XDR
* buffer has been destroyed, or even after calling xdr_inline_decode()
* on @xdr. It is therefore expected that the object it points to should
* be processed immediately.
*
* Return values:
* On success, returns size of object stored in *@ptr
* %-EBADMSG on XDR buffer overflow
* %-EMSGSIZE if the size of the object would exceed @maxlen
*/
static inline ssize_t
xdr_stream_decode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t maxlen)
{
__be32 *p;
__u32 len;
*ptr = NULL;
if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0))
return -EBADMSG;
if (len != 0) {
p = xdr_inline_decode(xdr, len);
if (unlikely(!p))
return -EBADMSG;
if (unlikely(len > maxlen))
return -EMSGSIZE;
*ptr = p;
}
return len;
}
#endif /* __KERNEL__ */ #endif /* __KERNEL__ */
#endif /* _SUNRPC_XDR_H_ */ #endif /* _SUNRPC_XDR_H_ */
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment