diff options
Diffstat (limited to 'net/sunrpc/xdr.c')
| -rw-r--r-- | net/sunrpc/xdr.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c index 5a6485946f3..a0af250ca31 100644 --- a/net/sunrpc/xdr.c +++ b/net/sunrpc/xdr.c @@ -1021,3 +1021,71 @@ xdr_encode_array2(struct xdr_buf *buf, unsigned int base, 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->page = 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); + |