Initial import

1 files changed, 110 insertions, 0 deletions

diff --git a/fs/nilfs2/alloc.h b/fs/nilfs2/alloc.h
new file mode 100644
index 000000000..4bd6451b5
--- /dev/null
+++ b/fs/nilfs2/alloc.h
@@ -0,0 +1,110 @@
+/*
+ * alloc.h - persistent object (dat entry/disk inode) allocator/deallocator
+ *
+ * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will 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 to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Original code was written by Koji Sato <koji@osrg.net>.
+ * Two allocators were unified by Ryusuke Konishi <ryusuke@osrg.net>,
+ *                                Amagai Yoshiji <amagai@osrg.net>.
+ */
+
+#ifndef _NILFS_ALLOC_H
+#define _NILFS_ALLOC_H
+
+#include <linux/types.h>
+#include <linux/buffer_head.h>
+#include <linux/fs.h>
+
+/**
+ * nilfs_palloc_entries_per_group - get the number of entries per group
+ * @inode: inode of metadata file using this allocator
+ *
+ * The number of entries per group is defined by the number of bits
+ * that a bitmap block can maintain.
+ */
+static inline unsigned long
+nilfs_palloc_entries_per_group(const struct inode *inode)
+{
+	return 1UL << (inode->i_blkbits + 3 /* log2(8 = CHAR_BITS) */);
+}
+
+int nilfs_palloc_init_blockgroup(struct inode *, unsigned);
+int nilfs_palloc_get_entry_block(struct inode *, __u64, int,
+				 struct buffer_head **);
+void *nilfs_palloc_block_get_entry(const struct inode *, __u64,
+				   const struct buffer_head *, void *);
+
+int nilfs_palloc_count_max_entries(struct inode *, u64, u64 *);
+
+/**
+ * nilfs_palloc_req - persistent allocator request and reply
+ * @pr_entry_nr: entry number (vblocknr or inode number)
+ * @pr_desc_bh: buffer head of the buffer containing block group descriptors
+ * @pr_bitmap_bh: buffer head of the buffer containing a block group bitmap
+ * @pr_entry_bh: buffer head of the buffer containing translation entries
+ */
+struct nilfs_palloc_req {
+	__u64 pr_entry_nr;
+	struct buffer_head *pr_desc_bh;
+	struct buffer_head *pr_bitmap_bh;
+	struct buffer_head *pr_entry_bh;
+};
+
+int nilfs_palloc_prepare_alloc_entry(struct inode *,
+				     struct nilfs_palloc_req *);
+void nilfs_palloc_commit_alloc_entry(struct inode *,
+				     struct nilfs_palloc_req *);
+void nilfs_palloc_abort_alloc_entry(struct inode *, struct nilfs_palloc_req *);
+void nilfs_palloc_commit_free_entry(struct inode *, struct nilfs_palloc_req *);
+int nilfs_palloc_prepare_free_entry(struct inode *, struct nilfs_palloc_req *);
+void nilfs_palloc_abort_free_entry(struct inode *, struct nilfs_palloc_req *);
+int nilfs_palloc_freev(struct inode *, __u64 *, size_t);
+
+#define nilfs_set_bit_atomic		ext2_set_bit_atomic
+#define nilfs_clear_bit_atomic		ext2_clear_bit_atomic
+#define nilfs_find_next_zero_bit	find_next_zero_bit_le
+
+/**
+ * struct nilfs_bh_assoc - block offset and buffer head association
+ * @blkoff: block offset
+ * @bh: buffer head
+ */
+struct nilfs_bh_assoc {
+	unsigned long blkoff;
+	struct buffer_head *bh;
+};
+
+/**
+ * struct nilfs_palloc_cache - persistent object allocator cache
+ * @lock: cache protecting lock
+ * @prev_desc: blockgroup descriptors cache
+ * @prev_bitmap: blockgroup bitmap cache
+ * @prev_entry: translation entries cache
+ */
+struct nilfs_palloc_cache {
+	spinlock_t lock;
+	struct nilfs_bh_assoc prev_desc;
+	struct nilfs_bh_assoc prev_bitmap;
+	struct nilfs_bh_assoc prev_entry;
+};
+
+void nilfs_palloc_setup_cache(struct inode *inode,
+			      struct nilfs_palloc_cache *cache);
+void nilfs_palloc_clear_cache(struct inode *inode);
+void nilfs_palloc_destroy_cache(struct inode *inode);
+
+#endif	/* _NILFS_ALLOC_H */