xfs: split out symlink code into it's own file.

The symlink code is about to get more complicated when CRCs are
added for remote symlink blocks. The symlink management code is
mostly self contained, so move it to it's own files so that all the
new code and the existing symlink code will not be intermingled
with other unrelated code.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

fs/xfs/Makefile

@@ -45,11 +45,11 @@ xfs-y				+= xfs_aops.o \
 				   xfs_itable.o \
 				   xfs_message.o \
 				   xfs_mru_cache.o \
-				   xfs_super.o \
-				   xfs_xattr.o \
 				   xfs_rename.o \
+				   xfs_super.o \
 				   xfs_utils.o \
 				   xfs_vnodeops.o \
+				   xfs_xattr.o \
 				   kmem.o \
 				   uuid.o
 
@@ -73,6 +73,7 @@ xfs-y				+= xfs_alloc.o \
 				   xfs_inode.o \
 				   xfs_log_recover.o \
 				   xfs_mount.o \
+				   xfs_symlink.o \
 				   xfs_trans.o
 
 # low-level transaction/log code

fs/xfs/xfs_bmap.c

@@ -47,6 +47,7 @@
 #include "xfs_filestream.h"
 #include "xfs_vnodeops.h"
 #include "xfs_trace.h"
+#include "xfs_symlink.h"
 
 
 kmem_zone_t		*xfs_bmap_free_item_zone;
@@ -1321,9 +1322,10 @@ xfs_bmap_add_attrfork_extents(
 }
 
 /*
- * Block initialisation functions for local to extent format conversion.
- * As these get more complex, they will be moved to the relevant files,
- * but for now they are too simple to worry about.
+ * Block initialisation function for local to extent format conversion.
+ *
+ * This shouldn't actually be called by anyone, so make sure debug kernels cause
+ * a noticable failure.
  */
 STATIC void
 xfs_bmap_local_to_extents_init_fn(
@@ -1332,23 +1334,12 @@ xfs_bmap_local_to_extents_init_fn(
 	struct xfs_inode	*ip,
 	struct xfs_ifork	*ifp)
 {
+	ASSERT(0);
 	bp->b_ops = &xfs_bmbt_buf_ops;
 	memcpy(bp->b_addr, ifp->if_u1.if_data, ifp->if_bytes);
 	xfs_trans_buf_set_type(tp, bp, XFS_BLF_BTREE_BUF);
 }
 
-STATIC void
-xfs_symlink_local_to_remote(
-	struct xfs_trans	*tp,
-	struct xfs_buf		*bp,
-	struct xfs_inode	*ip,
-	struct xfs_ifork	*ifp)
-{
-	/* remote symlink blocks are not verifiable until CRCs come along */
-	bp->b_ops = NULL;
-	memcpy(bp->b_addr, ifp->if_u1.if_data, ifp->if_bytes);
-}
-
 /*
  * Called from xfs_bmap_add_attrfork to handle local format files. Each
  * different data fork content type needs a different callout to do the

fs/xfs/xfs_symlink.h

+/*
+ * Copyright (c) 2012 Red Hat, Inc. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+#ifndef __XFS_SYMLINK_H
+#define __XFS_SYMLINK_H 1
+
+/*
+ * The maximum pathlen is 1024 bytes. Since the minimum file system
+ * blocksize is 512 bytes, we can get a max of 2 extents back from
+ * bmapi.
+ */
+#define XFS_SYMLINK_MAPS 2
+
+void xfs_symlink_local_to_remote(struct xfs_trans *tp, struct xfs_buf *bp,
+				 struct xfs_inode *ip, struct xfs_ifork *ifp);
+
+#ifdef __KERNEL__
+
+int xfs_symlink(struct xfs_inode *dp, struct xfs_name *link_name,
+		const char *target_path, umode_t mode, struct xfs_inode **ipp);
+int xfs_readlink(struct xfs_inode *ip, char *link);
+int xfs_inactive_symlink_rmt(struct xfs_inode *ip, struct xfs_trans **tpp);
+
+#endif /* __KERNEL__ */
+#endif /* __XFS_SYMLINK_H */