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-rw-r--r--fs/nilfs2/bmap.h280
1 files changed, 280 insertions, 0 deletions
diff --git a/fs/nilfs2/bmap.h b/fs/nilfs2/bmap.h
new file mode 100644
index 000000000..bfa817ce4
--- /dev/null
+++ b/fs/nilfs2/bmap.h
@@ -0,0 +1,280 @@
+/*
+ * bmap.h - NILFS block mapping.
+ *
+ * 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
+ *
+ * Written by Koji Sato <koji@osrg.net>.
+ */
+
+#ifndef _NILFS_BMAP_H
+#define _NILFS_BMAP_H
+
+#include <linux/types.h>
+#include <linux/fs.h>
+#include <linux/buffer_head.h>
+#include <linux/nilfs2_fs.h>
+#include "alloc.h"
+#include "dat.h"
+
+#define NILFS_BMAP_INVALID_PTR 0
+
+#define nilfs_bmap_keydiff_abs(diff) ((diff) < 0 ? -(diff) : (diff))
+
+
+struct nilfs_bmap;
+
+/**
+ * union nilfs_bmap_ptr_req - request for bmap ptr
+ * @bpr_ptr: bmap pointer
+ * @bpr_req: request for persistent allocator
+ */
+union nilfs_bmap_ptr_req {
+ __u64 bpr_ptr;
+ struct nilfs_palloc_req bpr_req;
+};
+
+/**
+ * struct nilfs_bmap_stats - bmap statistics
+ * @bs_nblocks: number of blocks created or deleted
+ */
+struct nilfs_bmap_stats {
+ unsigned int bs_nblocks;
+};
+
+/**
+ * struct nilfs_bmap_operations - bmap operation table
+ */
+struct nilfs_bmap_operations {
+ int (*bop_lookup)(const struct nilfs_bmap *, __u64, int, __u64 *);
+ int (*bop_lookup_contig)(const struct nilfs_bmap *, __u64, __u64 *,
+ unsigned);
+ int (*bop_insert)(struct nilfs_bmap *, __u64, __u64);
+ int (*bop_delete)(struct nilfs_bmap *, __u64);
+ void (*bop_clear)(struct nilfs_bmap *);
+
+ int (*bop_propagate)(struct nilfs_bmap *, struct buffer_head *);
+ void (*bop_lookup_dirty_buffers)(struct nilfs_bmap *,
+ struct list_head *);
+
+ int (*bop_assign)(struct nilfs_bmap *,
+ struct buffer_head **,
+ sector_t,
+ union nilfs_binfo *);
+ int (*bop_mark)(struct nilfs_bmap *, __u64, int);
+
+ int (*bop_seek_key)(const struct nilfs_bmap *, __u64, __u64 *);
+ int (*bop_last_key)(const struct nilfs_bmap *, __u64 *);
+
+ /* The following functions are internal use only. */
+ int (*bop_check_insert)(const struct nilfs_bmap *, __u64);
+ int (*bop_check_delete)(struct nilfs_bmap *, __u64);
+ int (*bop_gather_data)(struct nilfs_bmap *, __u64 *, __u64 *, int);
+};
+
+
+#define NILFS_BMAP_SIZE (NILFS_INODE_BMAP_SIZE * sizeof(__le64))
+#define NILFS_BMAP_KEY_BIT (sizeof(unsigned long) * 8 /* CHAR_BIT */)
+#define NILFS_BMAP_NEW_PTR_INIT \
+ (1UL << (sizeof(unsigned long) * 8 /* CHAR_BIT */ - 1))
+
+static inline int nilfs_bmap_is_new_ptr(unsigned long ptr)
+{
+ return !!(ptr & NILFS_BMAP_NEW_PTR_INIT);
+}
+
+
+/**
+ * struct nilfs_bmap - bmap structure
+ * @b_u: raw data
+ * @b_sem: semaphore
+ * @b_inode: owner of bmap
+ * @b_ops: bmap operation table
+ * @b_last_allocated_key: last allocated key for data block
+ * @b_last_allocated_ptr: last allocated ptr for data block
+ * @b_ptr_type: pointer type
+ * @b_state: state
+ * @b_nchildren_per_block: maximum number of child nodes for non-root nodes
+ */
+struct nilfs_bmap {
+ union {
+ __u8 u_flags;
+ __le64 u_data[NILFS_BMAP_SIZE / sizeof(__le64)];
+ } b_u;
+ struct rw_semaphore b_sem;
+ struct inode *b_inode;
+ const struct nilfs_bmap_operations *b_ops;
+ __u64 b_last_allocated_key;
+ __u64 b_last_allocated_ptr;
+ int b_ptr_type;
+ int b_state;
+ __u16 b_nchildren_per_block;
+};
+
+/* pointer type */
+#define NILFS_BMAP_PTR_P 0 /* physical block number (i.e. LBN) */
+#define NILFS_BMAP_PTR_VS 1 /* virtual block number (single
+ version) */
+#define NILFS_BMAP_PTR_VM 2 /* virtual block number (has multiple
+ versions) */
+#define NILFS_BMAP_PTR_U (-1) /* never perform pointer operations */
+
+#define NILFS_BMAP_USE_VBN(bmap) ((bmap)->b_ptr_type > 0)
+
+/* state */
+#define NILFS_BMAP_DIRTY 0x00000001
+
+/**
+ * struct nilfs_bmap_store - shadow copy of bmap state
+ * @data: cached raw block mapping of on-disk inode
+ * @last_allocated_key: cached value of last allocated key for data block
+ * @last_allocated_ptr: cached value of last allocated ptr for data block
+ * @state: cached value of state field of bmap structure
+ */
+struct nilfs_bmap_store {
+ __le64 data[NILFS_BMAP_SIZE / sizeof(__le64)];
+ __u64 last_allocated_key;
+ __u64 last_allocated_ptr;
+ int state;
+};
+
+int nilfs_bmap_test_and_clear_dirty(struct nilfs_bmap *);
+int nilfs_bmap_read(struct nilfs_bmap *, struct nilfs_inode *);
+void nilfs_bmap_write(struct nilfs_bmap *, struct nilfs_inode *);
+int nilfs_bmap_lookup_contig(struct nilfs_bmap *, __u64, __u64 *, unsigned);
+int nilfs_bmap_insert(struct nilfs_bmap *bmap, __u64 key, unsigned long rec);
+int nilfs_bmap_delete(struct nilfs_bmap *bmap, __u64 key);
+int nilfs_bmap_seek_key(struct nilfs_bmap *bmap, __u64 start, __u64 *keyp);
+int nilfs_bmap_last_key(struct nilfs_bmap *bmap, __u64 *keyp);
+int nilfs_bmap_truncate(struct nilfs_bmap *bmap, __u64 key);
+void nilfs_bmap_clear(struct nilfs_bmap *);
+int nilfs_bmap_propagate(struct nilfs_bmap *, struct buffer_head *);
+void nilfs_bmap_lookup_dirty_buffers(struct nilfs_bmap *, struct list_head *);
+int nilfs_bmap_assign(struct nilfs_bmap *, struct buffer_head **,
+ unsigned long, union nilfs_binfo *);
+int nilfs_bmap_lookup_at_level(struct nilfs_bmap *, __u64, int, __u64 *);
+int nilfs_bmap_mark(struct nilfs_bmap *, __u64, int);
+
+void nilfs_bmap_init_gc(struct nilfs_bmap *);
+
+void nilfs_bmap_save(const struct nilfs_bmap *, struct nilfs_bmap_store *);
+void nilfs_bmap_restore(struct nilfs_bmap *, const struct nilfs_bmap_store *);
+
+static inline int nilfs_bmap_lookup(struct nilfs_bmap *bmap, __u64 key,
+ __u64 *ptr)
+{
+ return nilfs_bmap_lookup_at_level(bmap, key, 1, ptr);
+}
+
+/*
+ * Internal use only
+ */
+struct inode *nilfs_bmap_get_dat(const struct nilfs_bmap *);
+
+static inline int nilfs_bmap_prepare_alloc_ptr(struct nilfs_bmap *bmap,
+ union nilfs_bmap_ptr_req *req,
+ struct inode *dat)
+{
+ if (dat)
+ return nilfs_dat_prepare_alloc(dat, &req->bpr_req);
+ /* ignore target ptr */
+ req->bpr_ptr = bmap->b_last_allocated_ptr++;
+ return 0;
+}
+
+static inline void nilfs_bmap_commit_alloc_ptr(struct nilfs_bmap *bmap,
+ union nilfs_bmap_ptr_req *req,
+ struct inode *dat)
+{
+ if (dat)
+ nilfs_dat_commit_alloc(dat, &req->bpr_req);
+}
+
+static inline void nilfs_bmap_abort_alloc_ptr(struct nilfs_bmap *bmap,
+ union nilfs_bmap_ptr_req *req,
+ struct inode *dat)
+{
+ if (dat)
+ nilfs_dat_abort_alloc(dat, &req->bpr_req);
+ else
+ bmap->b_last_allocated_ptr--;
+}
+
+static inline int nilfs_bmap_prepare_end_ptr(struct nilfs_bmap *bmap,
+ union nilfs_bmap_ptr_req *req,
+ struct inode *dat)
+{
+ return dat ? nilfs_dat_prepare_end(dat, &req->bpr_req) : 0;
+}
+
+static inline void nilfs_bmap_commit_end_ptr(struct nilfs_bmap *bmap,
+ union nilfs_bmap_ptr_req *req,
+ struct inode *dat)
+{
+ if (dat)
+ nilfs_dat_commit_end(dat, &req->bpr_req,
+ bmap->b_ptr_type == NILFS_BMAP_PTR_VS);
+}
+
+static inline void nilfs_bmap_abort_end_ptr(struct nilfs_bmap *bmap,
+ union nilfs_bmap_ptr_req *req,
+ struct inode *dat)
+{
+ if (dat)
+ nilfs_dat_abort_end(dat, &req->bpr_req);
+}
+
+static inline void nilfs_bmap_set_target_v(struct nilfs_bmap *bmap, __u64 key,
+ __u64 ptr)
+{
+ bmap->b_last_allocated_key = key;
+ bmap->b_last_allocated_ptr = ptr;
+}
+
+__u64 nilfs_bmap_data_get_key(const struct nilfs_bmap *,
+ const struct buffer_head *);
+
+__u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *, __u64);
+__u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *);
+
+
+/* Assume that bmap semaphore is locked. */
+static inline int nilfs_bmap_dirty(const struct nilfs_bmap *bmap)
+{
+ return !!(bmap->b_state & NILFS_BMAP_DIRTY);
+}
+
+/* Assume that bmap semaphore is locked. */
+static inline void nilfs_bmap_set_dirty(struct nilfs_bmap *bmap)
+{
+ bmap->b_state |= NILFS_BMAP_DIRTY;
+}
+
+/* Assume that bmap semaphore is locked. */
+static inline void nilfs_bmap_clear_dirty(struct nilfs_bmap *bmap)
+{
+ bmap->b_state &= ~NILFS_BMAP_DIRTY;
+}
+
+
+#define NILFS_BMAP_LARGE 0x1
+
+#define NILFS_BMAP_SMALL_LOW NILFS_DIRECT_KEY_MIN
+#define NILFS_BMAP_SMALL_HIGH NILFS_DIRECT_KEY_MAX
+#define NILFS_BMAP_LARGE_LOW NILFS_BTREE_ROOT_NCHILDREN_MAX
+#define NILFS_BMAP_LARGE_HIGH NILFS_BTREE_KEY_MAX
+
+#endif /* _NILFS_BMAP_H */