rpc: move process_xdr_buf
Since process_xdr_buf() is useful outside of the kerberos-specific code, we
move it to net/sunrpc/xdr.c, export it, and rename it in keeping with xdr_*
naming convention of xdr.c.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 5a64859..a0af250 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -1021,3 +1021,71 @@
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);
+