* @buf: xdr_buf
* @len: bytes to remove from buf->head[0]
*
- * Shrinks XDR buffer's header kvec buf->head[0] by
+ * Shrinks XDR buffer's header kvec buf->head[0] by
* 'len' bytes. The extra data is not lost, but is instead
* moved into the inlined pages and/or the tail.
*/
* @buf: xdr_buf
* @len: bytes to remove from buf->pages
*
- * Shrinks XDR buffer's page array buf->pages by
+ * Shrinks XDR buffer's page array buf->pages by
* 'len' bytes. The extra data is not lost, but is instead
* moved into the tail.
*/
buf->buflen = buf->len = iov->iov_len;
}
-/* Sets subiov to the intersection of iov with the buffer of length len
- * starting base bytes after iov. Indicates empty intersection by setting
- * length of subiov to zero. Decrements len by length of subiov, sets base
- * to zero (or decrements it by length of iov if subiov is empty). */
-static void
-iov_subsegment(struct kvec *iov, struct kvec *subiov, int *base, int *len)
-{
- if (*base > iov->iov_len) {
- subiov->iov_base = NULL;
- subiov->iov_len = 0;
- *base -= iov->iov_len;
- } else {
- subiov->iov_base = iov->iov_base + *base;
- subiov->iov_len = min(*len, (int)iov->iov_len - *base);
- *base = 0;
- }
- *len -= subiov->iov_len;
-}
-
/* Sets subbuf to the portion of buf of length len beginning base bytes
* from the start of buf. Returns -1 if base of length are out of bounds. */
int
xdr_buf_subsegment(struct xdr_buf *buf, struct xdr_buf *subbuf,
- int base, int len)
+ unsigned int base, unsigned int len)
{
- int i;
-
subbuf->buflen = subbuf->len = len;
- iov_subsegment(buf->head, subbuf->head, &base, &len);
+ if (base < buf->head[0].iov_len) {
+ subbuf->head[0].iov_base = buf->head[0].iov_base + base;
+ subbuf->head[0].iov_len = min_t(unsigned int, len,
+ buf->head[0].iov_len - base);
+ len -= subbuf->head[0].iov_len;
+ base = 0;
+ } else {
+ subbuf->head[0].iov_base = NULL;
+ subbuf->head[0].iov_len = 0;
+ base -= buf->head[0].iov_len;
+ }
if (base < buf->page_len) {
- i = (base + buf->page_base) >> PAGE_CACHE_SHIFT;
- subbuf->pages = &buf->pages[i];
- subbuf->page_base = (base + buf->page_base) & ~PAGE_CACHE_MASK;
- subbuf->page_len = min((int)buf->page_len - base, len);
+ subbuf->page_len = min(buf->page_len - base, len);
+ base += buf->page_base;
+ subbuf->page_base = base & ~PAGE_CACHE_MASK;
+ subbuf->pages = &buf->pages[base >> PAGE_CACHE_SHIFT];
len -= subbuf->page_len;
base = 0;
} else {
subbuf->page_len = 0;
}
- iov_subsegment(buf->tail, subbuf->tail, &base, &len);
+ if (base < buf->tail[0].iov_len) {
+ subbuf->tail[0].iov_base = buf->tail[0].iov_base + base;
+ subbuf->tail[0].iov_len = min_t(unsigned int, len,
+ buf->tail[0].iov_len - base);
+ len -= subbuf->tail[0].iov_len;
+ base = 0;
+ } else {
+ subbuf->tail[0].iov_base = NULL;
+ subbuf->tail[0].iov_len = 0;
+ base -= buf->tail[0].iov_len;
+ }
+
if (base || len)
return -1;
return 0;
}
-/* obj is assumed to point to allocated memory of size at least len: */
-int
-read_bytes_from_xdr_buf(struct xdr_buf *buf, int base, void *obj, int len)
+static void __read_bytes_from_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len)
{
- struct xdr_buf subbuf;
- int this_len;
- int status;
+ unsigned int this_len;
- status = xdr_buf_subsegment(buf, &subbuf, base, len);
- if (status)
- goto out;
- this_len = min(len, (int)subbuf.head[0].iov_len);
- memcpy(obj, subbuf.head[0].iov_base, this_len);
+ this_len = min_t(unsigned int, len, subbuf->head[0].iov_len);
+ memcpy(obj, subbuf->head[0].iov_base, this_len);
len -= this_len;
obj += this_len;
- this_len = min(len, (int)subbuf.page_len);
+ this_len = min_t(unsigned int, len, subbuf->page_len);
if (this_len)
- _copy_from_pages(obj, subbuf.pages, subbuf.page_base, this_len);
+ _copy_from_pages(obj, subbuf->pages, subbuf->page_base, this_len);
len -= this_len;
obj += this_len;
- this_len = min(len, (int)subbuf.tail[0].iov_len);
- memcpy(obj, subbuf.tail[0].iov_base, this_len);
-out:
- return status;
+ this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len);
+ memcpy(obj, subbuf->tail[0].iov_base, this_len);
}
/* obj is assumed to point to allocated memory of size at least len: */
-int
-write_bytes_to_xdr_buf(struct xdr_buf *buf, int base, void *obj, int len)
+int read_bytes_from_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, unsigned int len)
{
struct xdr_buf subbuf;
- int this_len;
int status;
status = xdr_buf_subsegment(buf, &subbuf, base, len);
- if (status)
- goto out;
- this_len = min(len, (int)subbuf.head[0].iov_len);
- memcpy(subbuf.head[0].iov_base, obj, this_len);
+ if (status != 0)
+ return status;
+ __read_bytes_from_xdr_buf(&subbuf, obj, len);
+ return 0;
+}
+
+static void __write_bytes_to_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len)
+{
+ unsigned int this_len;
+
+ this_len = min_t(unsigned int, len, subbuf->head[0].iov_len);
+ memcpy(subbuf->head[0].iov_base, obj, this_len);
len -= this_len;
obj += this_len;
- this_len = min(len, (int)subbuf.page_len);
+ this_len = min_t(unsigned int, len, subbuf->page_len);
if (this_len)
- _copy_to_pages(subbuf.pages, subbuf.page_base, obj, this_len);
+ _copy_to_pages(subbuf->pages, subbuf->page_base, obj, this_len);
len -= this_len;
obj += this_len;
- this_len = min(len, (int)subbuf.tail[0].iov_len);
- memcpy(subbuf.tail[0].iov_base, obj, this_len);
-out:
- return status;
+ this_len = min_t(unsigned int, len, subbuf->tail[0].iov_len);
+ memcpy(subbuf->tail[0].iov_base, obj, this_len);
+}
+
+/* obj is assumed to point to allocated memory of size at least len: */
+int write_bytes_to_xdr_buf(struct xdr_buf *buf, unsigned int base, void *obj, unsigned int len)
+{
+ struct xdr_buf subbuf;
+ int status;
+
+ status = xdr_buf_subsegment(buf, &subbuf, base, len);
+ if (status != 0)
+ return status;
+ __write_bytes_to_xdr_buf(&subbuf, obj, len);
+ return 0;
}
int
-xdr_decode_word(struct xdr_buf *buf, int base, u32 *obj)
+xdr_decode_word(struct xdr_buf *buf, unsigned int base, u32 *obj)
{
__be32 raw;
int status;
}
int
-xdr_encode_word(struct xdr_buf *buf, int base, u32 obj)
+xdr_encode_word(struct xdr_buf *buf, unsigned int base, u32 obj)
{
__be32 raw = htonl(obj);
* entirely in the head or the tail, set object to point to it; otherwise
* try to find space for it at the end of the tail, copy it there, and
* set obj to point to it. */
-int
-xdr_buf_read_netobj(struct xdr_buf *buf, struct xdr_netobj *obj, int offset)
+int xdr_buf_read_netobj(struct xdr_buf *buf, struct xdr_netobj *obj, unsigned int offset)
{
- u32 tail_offset = buf->head[0].iov_len + buf->page_len;
- u32 obj_end_offset;
+ struct xdr_buf subbuf;
if (xdr_decode_word(buf, offset, &obj->len))
- goto out;
- obj_end_offset = offset + 4 + obj->len;
-
- if (obj_end_offset <= buf->head[0].iov_len) {
- /* The obj is contained entirely in the head: */
- obj->data = buf->head[0].iov_base + offset + 4;
- } else if (offset + 4 >= tail_offset) {
- if (obj_end_offset - tail_offset
- > buf->tail[0].iov_len)
- goto out;
- /* The obj is contained entirely in the tail: */
- obj->data = buf->tail[0].iov_base
- + offset - tail_offset + 4;
- } else {
- /* use end of tail as storage for obj:
- * (We don't copy to the beginning because then we'd have
- * to worry about doing a potentially overlapping copy.
- * This assumes the object is at most half the length of the
- * tail.) */
- if (obj->len > buf->tail[0].iov_len)
- goto out;
- obj->data = buf->tail[0].iov_base + buf->tail[0].iov_len -
- obj->len;
- if (read_bytes_from_xdr_buf(buf, offset + 4,
- obj->data, obj->len))
- goto out;
+ return -EFAULT;
+ if (xdr_buf_subsegment(buf, &subbuf, offset + 4, obj->len))
+ return -EFAULT;
- }
+ /* Is the obj contained entirely in the head? */
+ obj->data = subbuf.head[0].iov_base;
+ if (subbuf.head[0].iov_len == obj->len)
+ return 0;
+ /* ..or is the obj contained entirely in the tail? */
+ obj->data = subbuf.tail[0].iov_base;
+ if (subbuf.tail[0].iov_len == obj->len)
+ return 0;
+
+ /* use end of tail as storage for obj:
+ * (We don't copy to the beginning because then we'd have
+ * to worry about doing a potentially overlapping copy.
+ * This assumes the object is at most half the length of the
+ * tail.) */
+ if (obj->len > buf->buflen - buf->len)
+ return -ENOMEM;
+ if (buf->tail[0].iov_len != 0)
+ obj->data = buf->tail[0].iov_base + buf->tail[0].iov_len;
+ else
+ obj->data = buf->head[0].iov_base + buf->head[0].iov_len;
+ __read_bytes_from_xdr_buf(&subbuf, obj->data, obj->len);
return 0;
-out:
- return -1;
}
/* Returns 0 on success, or else a negative error code. */
return xdr_xcode_array2(buf, base, desc, 1);
}
+
+int
+xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len,
+ int (*actor)(struct scatterlist *, void *), void *data)
+{
+ int i, ret = 0;
+ unsigned page_len, thislen, page_offset;
+ struct scatterlist sg[1];
+
+ if (offset >= buf->head[0].iov_len) {
+ offset -= buf->head[0].iov_len;
+ } else {
+ thislen = buf->head[0].iov_len - offset;
+ if (thislen > len)
+ thislen = len;
+ sg_set_buf(sg, buf->head[0].iov_base + offset, thislen);
+ ret = actor(sg, data);
+ if (ret)
+ goto out;
+ offset = 0;
+ len -= thislen;
+ }
+ if (len == 0)
+ goto out;
+
+ if (offset >= buf->page_len) {
+ offset -= buf->page_len;
+ } else {
+ page_len = buf->page_len - offset;
+ if (page_len > len)
+ page_len = len;
+ len -= page_len;
+ page_offset = (offset + buf->page_base) & (PAGE_CACHE_SIZE - 1);
+ i = (offset + buf->page_base) >> PAGE_CACHE_SHIFT;
+ thislen = PAGE_CACHE_SIZE - page_offset;
+ do {
+ if (thislen > page_len)
+ thislen = page_len;
+ sg_set_page(sg, buf->pages[i]);
+ sg->offset = page_offset;
+ sg->length = thislen;
+ ret = actor(sg, data);
+ if (ret)
+ goto out;
+ page_len -= thislen;
+ i++;
+ page_offset = 0;
+ thislen = PAGE_CACHE_SIZE;
+ } while (page_len != 0);
+ offset = 0;
+ }
+ if (len == 0)
+ goto out;
+ if (offset < buf->tail[0].iov_len) {
+ thislen = buf->tail[0].iov_len - offset;
+ if (thislen > len)
+ thislen = len;
+ sg_set_buf(sg, buf->tail[0].iov_base + offset, thislen);
+ ret = actor(sg, data);
+ len -= thislen;
+ }
+ if (len != 0)
+ ret = -EINVAL;
+out:
+ return ret;
+}
+EXPORT_SYMBOL(xdr_process_buf);
+
projects / linux-2.6-omap-h63xx.git / blobdiff