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Diffstat (limited to 'net/sunrpc/xdr.c')
-rw-r--r--net/sunrpc/xdr.c121
1 files changed, 64 insertions, 57 deletions
diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index f302c6eb8779..aa8177ddcbda 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -16,6 +16,7 @@
#include <linux/sunrpc/xdr.h>
#include <linux/sunrpc/msg_prot.h>
#include <linux/bvec.h>
+#include <trace/events/sunrpc.h>
/*
* XDR functions for basic NFS types
@@ -162,6 +163,15 @@ xdr_free_bvec(struct xdr_buf *buf)
buf->bvec = NULL;
}
+/**
+ * xdr_inline_pages - Prepare receive buffer for a large reply
+ * @xdr: xdr_buf into which reply will be placed
+ * @offset: expected offset where data payload will start, in bytes
+ * @pages: vector of struct page pointers
+ * @base: offset in first page where receive should start, in bytes
+ * @len: expected size of the upper layer data payload, in bytes
+ *
+ */
void
xdr_inline_pages(struct xdr_buf *xdr, unsigned int offset,
struct page **pages, unsigned int base, unsigned int len)
@@ -179,6 +189,8 @@ xdr_inline_pages(struct xdr_buf *xdr, unsigned int offset,
tail->iov_base = buf + offset;
tail->iov_len = buflen - offset;
+ if ((xdr->page_len & 3) == 0)
+ tail->iov_len -= sizeof(__be32);
xdr->buflen += len;
}
@@ -346,13 +358,15 @@ EXPORT_SYMBOL_GPL(_copy_from_pages);
* 'len' bytes. The extra data is not lost, but is instead
* moved into the inlined pages and/or the tail.
*/
-static void
+static unsigned int
xdr_shrink_bufhead(struct xdr_buf *buf, size_t len)
{
struct kvec *head, *tail;
size_t copy, offs;
unsigned int pglen = buf->page_len;
+ unsigned int result;
+ result = 0;
tail = buf->tail;
head = buf->head;
@@ -366,6 +380,7 @@ xdr_shrink_bufhead(struct xdr_buf *buf, size_t len)
copy = tail->iov_len - len;
memmove((char *)tail->iov_base + len,
tail->iov_base, copy);
+ result += copy;
}
/* Copy from the inlined pages into the tail */
copy = len;
@@ -376,11 +391,13 @@ xdr_shrink_bufhead(struct xdr_buf *buf, size_t len)
copy = 0;
else if (copy > tail->iov_len - offs)
copy = tail->iov_len - offs;
- if (copy != 0)
+ if (copy != 0) {
_copy_from_pages((char *)tail->iov_base + offs,
buf->pages,
buf->page_base + pglen + offs - len,
copy);
+ result += copy;
+ }
/* Do we also need to copy data from the head into the tail ? */
if (len > pglen) {
offs = copy = len - pglen;
@@ -390,6 +407,7 @@ xdr_shrink_bufhead(struct xdr_buf *buf, size_t len)
(char *)head->iov_base +
head->iov_len - offs,
copy);
+ result += copy;
}
}
/* Now handle pages */
@@ -405,12 +423,15 @@ xdr_shrink_bufhead(struct xdr_buf *buf, size_t len)
_copy_to_pages(buf->pages, buf->page_base,
(char *)head->iov_base + head->iov_len - len,
copy);
+ result += copy;
}
head->iov_len -= len;
buf->buflen -= len;
/* Have we truncated the message? */
if (buf->len > buf->buflen)
buf->len = buf->buflen;
+
+ return result;
}
/**
@@ -422,14 +443,16 @@ xdr_shrink_bufhead(struct xdr_buf *buf, size_t len)
* 'len' bytes. The extra data is not lost, but is instead
* moved into the tail.
*/
-static void
+static unsigned int
xdr_shrink_pagelen(struct xdr_buf *buf, size_t len)
{
struct kvec *tail;
size_t copy;
unsigned int pglen = buf->page_len;
unsigned int tailbuf_len;
+ unsigned int result;
+ result = 0;
tail = buf->tail;
BUG_ON (len > pglen);
@@ -447,18 +470,22 @@ xdr_shrink_pagelen(struct xdr_buf *buf, size_t len)
if (tail->iov_len > len) {
char *p = (char *)tail->iov_base + len;
memmove(p, tail->iov_base, tail->iov_len - len);
+ result += tail->iov_len - len;
} else
copy = tail->iov_len;
/* Copy from the inlined pages into the tail */
_copy_from_pages((char *)tail->iov_base,
buf->pages, buf->page_base + pglen - len,
copy);
+ result += copy;
}
buf->page_len -= len;
buf->buflen -= len;
/* Have we truncated the message? */
if (buf->len > buf->buflen)
buf->len = buf->buflen;
+
+ return result;
}
void
@@ -483,6 +510,7 @@ EXPORT_SYMBOL_GPL(xdr_stream_pos);
* @xdr: pointer to xdr_stream struct
* @buf: pointer to XDR buffer in which to encode data
* @p: current pointer inside XDR buffer
+ * @rqst: pointer to controlling rpc_rqst, for debugging
*
* Note: at the moment the RPC client only passes the length of our
* scratch buffer in the xdr_buf's header kvec. Previously this
@@ -491,7 +519,8 @@ EXPORT_SYMBOL_GPL(xdr_stream_pos);
* of the buffer length, and takes care of adjusting the kvec
* length for us.
*/
-void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p)
+void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p,
+ struct rpc_rqst *rqst)
{
struct kvec *iov = buf->head;
int scratch_len = buf->buflen - buf->page_len - buf->tail[0].iov_len;
@@ -513,6 +542,7 @@ void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p)
buf->len += len;
iov->iov_len += len;
}
+ xdr->rqst = rqst;
}
EXPORT_SYMBOL_GPL(xdr_init_encode);
@@ -551,9 +581,9 @@ static __be32 *xdr_get_next_encode_buffer(struct xdr_stream *xdr,
int frag1bytes, frag2bytes;
if (nbytes > PAGE_SIZE)
- return NULL; /* Bigger buffers require special handling */
+ goto out_overflow; /* Bigger buffers require special handling */
if (xdr->buf->len + nbytes > xdr->buf->buflen)
- return NULL; /* Sorry, we're totally out of space */
+ goto out_overflow; /* Sorry, we're totally out of space */
frag1bytes = (xdr->end - xdr->p) << 2;
frag2bytes = nbytes - frag1bytes;
if (xdr->iov)
@@ -582,6 +612,9 @@ static __be32 *xdr_get_next_encode_buffer(struct xdr_stream *xdr,
xdr->buf->page_len += frag2bytes;
xdr->buf->len += nbytes;
return p;
+out_overflow:
+ trace_rpc_xdr_overflow(xdr, nbytes);
+ return NULL;
}
/**
@@ -819,8 +852,10 @@ static bool xdr_set_next_buffer(struct xdr_stream *xdr)
* @xdr: pointer to xdr_stream struct
* @buf: pointer to XDR buffer from which to decode data
* @p: current pointer inside XDR buffer
+ * @rqst: pointer to controlling rpc_rqst, for debugging
*/
-void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p)
+void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p,
+ struct rpc_rqst *rqst)
{
xdr->buf = buf;
xdr->scratch.iov_base = NULL;
@@ -836,6 +871,7 @@ void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p)
xdr->nwords -= p - xdr->p;
xdr->p = p;
}
+ xdr->rqst = rqst;
}
EXPORT_SYMBOL_GPL(xdr_init_decode);
@@ -854,7 +890,7 @@ void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf,
buf->page_len = len;
buf->buflen = len;
buf->len = len;
- xdr_init_decode(xdr, buf, NULL);
+ xdr_init_decode(xdr, buf, NULL, NULL);
}
EXPORT_SYMBOL_GPL(xdr_init_decode_pages);
@@ -896,20 +932,23 @@ static __be32 *xdr_copy_to_scratch(struct xdr_stream *xdr, size_t nbytes)
size_t cplen = (char *)xdr->end - (char *)xdr->p;
if (nbytes > xdr->scratch.iov_len)
- return NULL;
+ goto out_overflow;
p = __xdr_inline_decode(xdr, cplen);
if (p == NULL)
return NULL;
memcpy(cpdest, p, cplen);
+ if (!xdr_set_next_buffer(xdr))
+ goto out_overflow;
cpdest += cplen;
nbytes -= cplen;
- if (!xdr_set_next_buffer(xdr))
- return NULL;
p = __xdr_inline_decode(xdr, nbytes);
if (p == NULL)
return NULL;
memcpy(cpdest, p, nbytes);
return xdr->scratch.iov_base;
+out_overflow:
+ trace_rpc_xdr_overflow(xdr, nbytes);
+ return NULL;
}
/**
@@ -926,14 +965,17 @@ __be32 * xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes)
{
__be32 *p;
- if (nbytes == 0)
+ if (unlikely(nbytes == 0))
return xdr->p;
if (xdr->p == xdr->end && !xdr_set_next_buffer(xdr))
- return NULL;
+ goto out_overflow;
p = __xdr_inline_decode(xdr, nbytes);
if (p != NULL)
return p;
return xdr_copy_to_scratch(xdr, nbytes);
+out_overflow:
+ trace_rpc_xdr_overflow(xdr, nbytes);
+ return NULL;
}
EXPORT_SYMBOL_GPL(xdr_inline_decode);
@@ -943,13 +985,17 @@ static unsigned int xdr_align_pages(struct xdr_stream *xdr, unsigned int len)
struct kvec *iov;
unsigned int nwords = XDR_QUADLEN(len);
unsigned int cur = xdr_stream_pos(xdr);
+ unsigned int copied, offset;
if (xdr->nwords == 0)
return 0;
+
/* Realign pages to current pointer position */
- iov = buf->head;
+ iov = buf->head;
if (iov->iov_len > cur) {
- xdr_shrink_bufhead(buf, iov->iov_len - cur);
+ offset = iov->iov_len - cur;
+ copied = xdr_shrink_bufhead(buf, offset);
+ trace_rpc_xdr_alignment(xdr, offset, copied);
xdr->nwords = XDR_QUADLEN(buf->len - cur);
}
@@ -961,7 +1007,9 @@ static unsigned int xdr_align_pages(struct xdr_stream *xdr, unsigned int len)
len = buf->page_len;
else if (nwords < xdr->nwords) {
/* Truncate page data and move it into the tail */
- xdr_shrink_pagelen(buf, buf->page_len - len);
+ offset = buf->page_len - len;
+ copied = xdr_shrink_pagelen(buf, offset);
+ trace_rpc_xdr_alignment(xdr, offset, copied);
xdr->nwords = XDR_QUADLEN(buf->len - cur);
}
return len;
@@ -1102,47 +1150,6 @@ xdr_buf_subsegment(struct xdr_buf *buf, struct xdr_buf *subbuf,
}
EXPORT_SYMBOL_GPL(xdr_buf_subsegment);
-/**
- * xdr_buf_trim - lop at most "len" bytes off the end of "buf"
- * @buf: buf to be trimmed
- * @len: number of bytes to reduce "buf" by
- *
- * Trim an xdr_buf by the given number of bytes by fixing up the lengths. Note
- * that it's possible that we'll trim less than that amount if the xdr_buf is
- * too small, or if (for instance) it's all in the head and the parser has
- * already read too far into it.
- */
-void xdr_buf_trim(struct xdr_buf *buf, unsigned int len)
-{
- size_t cur;
- unsigned int trim = len;
-
- if (buf->tail[0].iov_len) {
- cur = min_t(size_t, buf->tail[0].iov_len, trim);
- buf->tail[0].iov_len -= cur;
- trim -= cur;
- if (!trim)
- goto fix_len;
- }
-
- if (buf->page_len) {
- cur = min_t(unsigned int, buf->page_len, trim);
- buf->page_len -= cur;
- trim -= cur;
- if (!trim)
- goto fix_len;
- }
-
- if (buf->head[0].iov_len) {
- cur = min_t(size_t, buf->head[0].iov_len, trim);
- buf->head[0].iov_len -= cur;
- trim -= cur;
- }
-fix_len:
- buf->len -= (len - trim);
-}
-EXPORT_SYMBOL_GPL(xdr_buf_trim);
-
static void __read_bytes_from_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len)
{
unsigned int this_len;