xfs: move busy extent handling to it's own file

To make it easier to handle userspace code merges, move all the busy
extent handling out of the allocation code and into it's own file.
The userspace code does not need the busy extent code, so this
simplifies the merging of the kernel code into the userspace
xfsprogs library.

Because the busy extent code has been almost completely rewritten
over the past couple of years, also update the copyright on this new
file to include the authors that made all those changes.

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

1 files changed, 65 insertions, 0 deletions

diff --git a/fs/xfs/xfs_extent_busy.h b/fs/xfs/xfs_extent_busy.h
new file mode 100644
index 000000000000..671b501f13e5
--- /dev/null
+++ b/fs/xfs/xfs_extent_busy.h
@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
+ * Copyright (c) 2010 David Chinner.
+ * Copyright (c) 2011 Christoph Hellwig.
+ * 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_EXTENT_BUSY_H__
+#define __XFS_EXTENT_BUSY_H__
+
+/*
+ * Busy block/extent entry.  Indexed by a rbtree in perag to mark blocks that
+ * have been freed but whose transactions aren't committed to disk yet.
+ *
+ * Note that we use the transaction ID to record the transaction, not the
+ * transaction structure itself. See xfs_extent_busy_insert() for details.
+ */
+struct xfs_busy_extent {
+        struct rb_node  rb_node;        /* ag by-bno indexed search tree */
+        struct list_head list;          /* transaction busy extent list */
+        xfs_agnumber_t  agno;
+        xfs_agblock_t   bno;
+        xfs_extlen_t    length;
+        unsigned int    flags;
+#define XFS_ALLOC_BUSY_DISCARDED        0x01    /* undergoing a discard op. */
+#define XFS_ALLOC_BUSY_SKIP_DISCARD     0x02    /* do not discard */
+};
+
+void
+xfs_alloc_busy_insert(struct xfs_trans *tp, xfs_agnumber_t agno,
+        xfs_agblock_t bno, xfs_extlen_t len, unsigned int flags);
+
+void
+xfs_alloc_busy_clear(struct xfs_mount *mp, struct list_head *list,
+        bool do_discard);
+
+int
+xfs_alloc_busy_search(struct xfs_mount *mp, xfs_agnumber_t agno,
+        xfs_agblock_t bno, xfs_extlen_t len);
+
+void
+xfs_alloc_busy_reuse(struct xfs_mount *mp, xfs_agnumber_t agno,
+        xfs_agblock_t fbno, xfs_extlen_t flen, bool userdata);
+
+int
+xfs_alloc_busy_ag_cmp(void *priv, struct list_head *a, struct list_head *b);
+
+static inline void xfs_alloc_busy_sort(struct list_head *list)
+{
+        list_sort(NULL, list, xfs_alloc_busy_ag_cmp);
+}
+
+#endif /* __XFS_EXTENT_BUSY_H__ */