xfs: create xfs_bmap_util.[ch]

There is a bunch of code in xfs_bmap.c that is kernel specific and
not shared with userspace. To minimise the difference between the
kernel and userspace code, shift this unshared code to
xfs_bmap_util.c, and the declarations to xfs_bmap_util.h.

The biggest issue here is xfs_bmap_finish() - userspace has it's own
definition of this function, and so we need to move it out of
xfs_bmap.[ch]. This means several other files need to include
xfs_bmap_util.h as well.

It also introduces and interesting dance for the stack switching
code in xfs_bmapi_allocate(). The stack switching/workqueue code is
actually moved to xfs_bmap_util.c, so that userspace can simply use
a #define in a header file to connect the dots without needing to
know about the stack switch code at all.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

1 files changed, 96 insertions, 0 deletions

diff --git a/fs/xfs/xfs_bmap_util.h b/fs/xfs/xfs_bmap_util.h
new file mode 100644
index 000000000000..004fe4b28d49
--- /dev/null
+++ b/fs/xfs/xfs_bmap_util.h
@@ -0,0 +1,96 @@
+/*
+ * Copyright (c) 2000-2006 Silicon Graphics, 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_BMAP_UTIL_H__
+#define	__XFS_BMAP_UTIL_H__
+
+/* Kernel only BMAP related definitions and functions */
+
+struct xfs_bmbt_irec;
+struct xfs_ifork;
+struct xfs_inode;
+struct xfs_mount;
+struct xfs_trans;
+
+/*
+ * Argument structure for xfs_bmap_alloc.
+ */
+struct xfs_bmalloca {
+	xfs_fsblock_t		*firstblock; /* i/o first block allocated */
+	struct xfs_bmap_free	*flist;	/* bmap freelist */
+	struct xfs_trans	*tp;	/* transaction pointer */
+	struct xfs_inode	*ip;	/* incore inode pointer */
+	struct xfs_bmbt_irec	prev;	/* extent before the new one */
+	struct xfs_bmbt_irec	got;	/* extent after, or delayed */
+
+	xfs_fileoff_t		offset;	/* offset in file filling in */
+	xfs_extlen_t		length;	/* i/o length asked/allocated */
+	xfs_fsblock_t		blkno;	/* starting block of new extent */
+
+	struct xfs_btree_cur	*cur;	/* btree cursor */
+	xfs_extnum_t		idx;	/* current extent index */
+	int			nallocs;/* number of extents alloc'd */
+	int			logflags;/* flags for transaction logging */
+
+	xfs_extlen_t		total;	/* total blocks needed for xaction */
+	xfs_extlen_t		minlen;	/* minimum allocation size (blocks) */
+	xfs_extlen_t		minleft; /* amount must be left after alloc */
+	char			eof;	/* set if allocating past last extent */
+	char			wasdel;	/* replacing a delayed allocation */
+	char			userdata;/* set if is user data */
+	char			aeof;	/* allocated space at eof */
+	char			conv;	/* overwriting unwritten extents */
+	char			stack_switch;
+	int			flags;
+	struct completion	*done;
+	struct work_struct	work;
+	int			result;
+};
+
+int	xfs_bmap_finish(struct xfs_trans **tp, struct xfs_bmap_free *flist,
+			int *committed);
+int	xfs_bmap_rtalloc(struct xfs_bmalloca *ap);
+int	xfs_bmapi_allocate(struct xfs_bmalloca *args);
+int	__xfs_bmapi_allocate(struct xfs_bmalloca *args);
+int	xfs_bmap_eof(struct xfs_inode *ip, xfs_fileoff_t endoff,
+		     int whichfork, int *eof);
+int	xfs_bmap_count_blocks(struct xfs_trans *tp, struct xfs_inode *ip,
+			      int whichfork, int *count);
+int	xfs_bmap_punch_delalloc_range(struct xfs_inode *ip,
+		xfs_fileoff_t start_fsb, xfs_fileoff_t length);
+
+/* bmap to userspace formatter - copy to user & advance pointer */
+typedef int (*xfs_bmap_format_t)(void **, struct getbmapx *, int *);
+int	xfs_getbmap(struct xfs_inode *ip, struct getbmapx *bmv,
+		xfs_bmap_format_t formatter, void *arg);
+
+/* functions in xfs_bmap.c that are only needed by xfs_bmap_util.c */
+void	xfs_bmap_del_free(struct xfs_bmap_free *flist,
+			  struct xfs_bmap_free_item *prev,
+			  struct xfs_bmap_free_item *free);
+int	xfs_bmap_extsize_align(struct xfs_mount *mp, struct xfs_bmbt_irec *gotp,
+			       struct xfs_bmbt_irec *prevp, xfs_extlen_t extsz,
+			       int rt, int eof, int delay, int convert,
+			       xfs_fileoff_t *offp, xfs_extlen_t *lenp);
+void	xfs_bmap_adjacent(struct xfs_bmalloca *ap);
+int	xfs_bmap_last_extent(struct xfs_trans *tp, struct xfs_inode *ip,
+			     int whichfork, struct xfs_bmbt_irec *rec,
+			     int *is_empty);
+
+xfs_daddr_t xfs_fsb_to_db(struct xfs_inode *ip, xfs_fsblock_t fsb);
+
+#endif	/* __XFS_BMAP_UTIL_H__ */