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>

include/linux/sunrpc/xdr.h

@@ -11,6 +11,7 @@
 
 #include <linux/uio.h>
 #include <asm/byteorder.h>
+#include <linux/scatterlist.h>
 
 /*
  * Buffer adjustment
@@ -196,6 +197,7 @@ extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32
 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
 extern void xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
+extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
 
 #endif /* __KERNEL__ */
 

net/sunrpc/auth_gss/gss_krb5_crypto.c

@@ -43,6 +43,7 @@
 #include <linux/highmem.h>
 #include <linux/pagemap.h>
 #include <linux/sunrpc/gss_krb5.h>
+#include <linux/sunrpc/xdr.h>
 
 #ifdef RPC_DEBUG
 # define RPCDBG_FACILITY        RPCDBG_AUTH
@@ -119,72 +120,6 @@ out:
 
 EXPORT_SYMBOL(krb5_decrypt);
 
-static int
-process_xdr_buf(struct xdr_buf *buf, int offset, int len,
-		int (*actor)(struct scatterlist *, void *), void *data)
-{
-	int i, page_len, thislen, page_offset, ret = 0;
-	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;
-}
-
 static int
 checksummer(struct scatterlist *sg, void *data)
 {
@@ -225,7 +160,7 @@ make_checksum(s32 cksumtype, char *header, int hdrlen, struct xdr_buf *body,
 	err = crypto_hash_update(&desc, sg, hdrlen);
 	if (err)
 		goto out;
-	err = process_xdr_buf(body, body_offset, body->len - body_offset,
+	err = xdr_process_buf(body, body_offset, body->len - body_offset,
 			      checksummer, &desc);
 	if (err)
 		goto out;
@@ -323,7 +258,7 @@ gss_encrypt_xdr_buf(struct crypto_blkcipher *tfm, struct xdr_buf *buf,
 	desc.fragno = 0;
 	desc.fraglen = 0;
 
-	ret = process_xdr_buf(buf, offset, buf->len - offset, encryptor, &desc);
+	ret = xdr_process_buf(buf, offset, buf->len - offset, encryptor, &desc);
 	return ret;
 }
 
@@ -389,7 +324,7 @@ gss_decrypt_xdr_buf(struct crypto_blkcipher *tfm, struct xdr_buf *buf,
 	desc.desc.flags = 0;
 	desc.fragno = 0;
 	desc.fraglen = 0;
-	return process_xdr_buf(buf, offset, buf->len - offset, decryptor, &desc);
+	return xdr_process_buf(buf, offset, buf->len - offset, decryptor, &desc);
 }
 
 EXPORT_SYMBOL(gss_decrypt_xdr_buf);

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);
+