Pull bugzilla-7349 into test branch

[powerpc.git] / net / sunrpc / xdr.c

diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 5a64859..a0af250 100644 (file)
--- 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);
+