]> git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blame - fs/nilfs2/the_nilfs.h
fs/befs/btree.c: remove typedef befs_btree_node
[mirror_ubuntu-zesty-kernel.git] / fs / nilfs2 / the_nilfs.h
CommitLineData
65b4643d
RK
1/*
2 * the_nilfs.h - the_nilfs shared structure.
3 *
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 *
20 * Written by Ryusuke Konishi <ryusuke@osrg.net>
21 *
22 */
23
24#ifndef _THE_NILFS_H
25#define _THE_NILFS_H
26
27#include <linux/types.h>
28#include <linux/buffer_head.h>
ba65ae47 29#include <linux/rbtree.h>
65b4643d
RK
30#include <linux/fs.h>
31#include <linux/blkdev.h>
32#include <linux/backing-dev.h>
5a0e3ad6 33#include <linux/slab.h>
65b4643d 34
3fd3fe5a 35struct nilfs_sc_info;
caa05d49 36struct nilfs_sysfs_dev_subgroups;
3fd3fe5a 37
65b4643d
RK
38/* the_nilfs struct */
39enum {
40 THE_NILFS_INIT = 0, /* Information from super_block is set */
65b4643d 41 THE_NILFS_DISCONTINUED, /* 'next' pointer chain has broken */
1cf58fa8 42 THE_NILFS_GC_RUNNING, /* gc process is running */
e605f0a7 43 THE_NILFS_SB_DIRTY, /* super block is dirty */
65b4643d
RK
44};
45
46/**
47 * struct the_nilfs - struct to supervise multiple nilfs mount points
48 * @ns_flags: flags
65b4643d 49 * @ns_bdev: block device
65b4643d 50 * @ns_sem: semaphore for shared states
572d8b39 51 * @ns_snapshot_mount_mutex: mutex to protect snapshot mounts
e339ad31
RK
52 * @ns_sbh: buffer heads of on-disk super blocks
53 * @ns_sbp: pointers to super block data
b2ac86e1
JS
54 * @ns_sbwtime: previous write time of super block
55 * @ns_sbwcount: write count of super block
e339ad31 56 * @ns_sbsize: size of valid data in super block
6b0f3393 57 * @ns_mount_state: file system state
caa05d49 58 * @ns_sb_update_freq: interval of periodical update of superblocks (in seconds)
65b4643d
RK
59 * @ns_seg_seq: segment sequence counter
60 * @ns_segnum: index number of the latest full segment.
61 * @ns_nextnum: index number of the full segment index to be used next
62 * @ns_pseg_offset: offset of next partial segment in the current full segment
63 * @ns_cno: next checkpoint number
64 * @ns_ctime: write time of the last segment
65 * @ns_nongc_ctime: write time of the last segment not for cleaner operation
66 * @ns_ndirtyblks: Number of dirty data blocks
67 * @ns_last_segment_lock: lock protecting fields for the latest segment
68 * @ns_last_pseg: start block number of the latest segment
69 * @ns_last_seq: sequence value of the latest segment
70 * @ns_last_cno: checkpoint number of the latest segment
2c2e52fc 71 * @ns_prot_seq: least sequence number of segments which must not be reclaimed
32502047 72 * @ns_prev_seq: base sequence number used to decide if advance log cursor
3fd3fe5a
RK
73 * @ns_writer: log writer
74 * @ns_segctor_sem: semaphore protecting log write
65b4643d
RK
75 * @ns_dat: DAT file inode
76 * @ns_cpfile: checkpoint file inode
77 * @ns_sufile: segusage file inode
ba65ae47
RK
78 * @ns_cptree: rb-tree of all mounted checkpoints (nilfs_root)
79 * @ns_cptree_lock: lock protecting @ns_cptree
693dd321
RK
80 * @ns_dirty_files: list of dirty files
81 * @ns_inode_lock: lock protecting @ns_dirty_files
65b4643d 82 * @ns_gc_inodes: dummy inodes to keep live blocks
9b1fc4e4
RK
83 * @ns_next_generation: next generation number for inodes
84 * @ns_next_gen_lock: lock protecting @ns_next_generation
3b2ce58b 85 * @ns_mount_opt: mount options
574e6c31
RK
86 * @ns_resuid: uid for reserved blocks
87 * @ns_resgid: gid for reserved blocks
88 * @ns_interval: checkpoint creation interval
89 * @ns_watermark: watermark for the number of dirty buffers
65b4643d 90 * @ns_blocksize_bits: bit length of block size
92c60cca 91 * @ns_blocksize: block size
65b4643d
RK
92 * @ns_nsegments: number of segments in filesystem
93 * @ns_blocks_per_segment: number of blocks per segment
94 * @ns_r_segments_percentage: reserved segments percentage
95 * @ns_nrsvsegs: number of reserved segments
96 * @ns_first_data_block: block number of first data block
97 * @ns_inode_size: size of on-disk inode
98 * @ns_first_ino: first not-special inode number
99 * @ns_crc_seed: seed value of CRC32 calculation
da7141fb
VD
100 * @ns_dev_kobj: /sys/fs/<nilfs>/<device>
101 * @ns_dev_kobj_unregister: completion state
caa05d49 102 * @ns_dev_subgroups: <device> subgroups pointer
65b4643d
RK
103 */
104struct the_nilfs {
105 unsigned long ns_flags;
65b4643d
RK
106
107 struct block_device *ns_bdev;
65b4643d 108 struct rw_semaphore ns_sem;
572d8b39 109 struct mutex ns_snapshot_mount_mutex;
65b4643d
RK
110
111 /*
112 * used for
113 * - loading the latest checkpoint exclusively.
114 * - allocating a new full segment.
65b4643d 115 */
e339ad31
RK
116 struct buffer_head *ns_sbh[2];
117 struct nilfs_super_block *ns_sbp[2];
b2ac86e1
JS
118 time_t ns_sbwtime;
119 unsigned ns_sbwcount;
e339ad31 120 unsigned ns_sbsize;
65b4643d 121 unsigned ns_mount_state;
caa05d49 122 unsigned ns_sb_update_freq;
65b4643d
RK
123
124 /*
125 * Following fields are dedicated to a writable FS-instance.
126 * Except for the period seeking checkpoint, code outside the segment
47420c79
RK
127 * constructor must lock a segment semaphore while accessing these
128 * fields.
65b4643d
RK
129 * The writable FS-instance is sole during a lifetime of the_nilfs.
130 */
131 u64 ns_seg_seq;
132 __u64 ns_segnum;
133 __u64 ns_nextnum;
134 unsigned long ns_pseg_offset;
135 __u64 ns_cno;
136 time_t ns_ctime;
137 time_t ns_nongc_ctime;
138 atomic_t ns_ndirtyblks;
139
140 /*
141 * The following fields hold information on the latest partial segment
142 * written to disk with a super root. These fields are protected by
143 * ns_last_segment_lock.
144 */
145 spinlock_t ns_last_segment_lock;
146 sector_t ns_last_pseg;
147 u64 ns_last_seq;
148 __u64 ns_last_cno;
2c2e52fc 149 u64 ns_prot_seq;
32502047 150 u64 ns_prev_seq;
65b4643d 151
3fd3fe5a 152 struct nilfs_sc_info *ns_writer;
65b4643d
RK
153 struct rw_semaphore ns_segctor_sem;
154
155 /*
156 * Following fields are lock free except for the period before
157 * the_nilfs is initialized.
158 */
159 struct inode *ns_dat;
160 struct inode *ns_cpfile;
161 struct inode *ns_sufile;
65b4643d 162
ba65ae47
RK
163 /* Checkpoint tree */
164 struct rb_root ns_cptree;
165 spinlock_t ns_cptree_lock;
166
693dd321
RK
167 /* Dirty inode list */
168 struct list_head ns_dirty_files;
169 spinlock_t ns_inode_lock;
170
263d90ce 171 /* GC inode list */
65b4643d 172 struct list_head ns_gc_inodes;
65b4643d 173
9b1fc4e4
RK
174 /* Inode allocator */
175 u32 ns_next_generation;
176 spinlock_t ns_next_gen_lock;
177
3b2ce58b
RK
178 /* Mount options */
179 unsigned long ns_mount_opt;
180
574e6c31
RK
181 uid_t ns_resuid;
182 gid_t ns_resgid;
183 unsigned long ns_interval;
184 unsigned long ns_watermark;
185
65b4643d
RK
186 /* Disk layout information (static) */
187 unsigned int ns_blocksize_bits;
92c60cca 188 unsigned int ns_blocksize;
65b4643d
RK
189 unsigned long ns_nsegments;
190 unsigned long ns_blocks_per_segment;
191 unsigned long ns_r_segments_percentage;
192 unsigned long ns_nrsvsegs;
193 unsigned long ns_first_data_block;
194 int ns_inode_size;
195 int ns_first_ino;
196 u32 ns_crc_seed;
da7141fb
VD
197
198 /* /sys/fs/<nilfs>/<device> */
199 struct kobject ns_dev_kobj;
200 struct completion ns_dev_kobj_unregister;
caa05d49 201 struct nilfs_sysfs_dev_subgroups *ns_dev_subgroups;
65b4643d
RK
202};
203
65b4643d
RK
204#define THE_NILFS_FNS(bit, name) \
205static inline void set_nilfs_##name(struct the_nilfs *nilfs) \
206{ \
207 set_bit(THE_NILFS_##bit, &(nilfs)->ns_flags); \
208} \
209static inline void clear_nilfs_##name(struct the_nilfs *nilfs) \
210{ \
211 clear_bit(THE_NILFS_##bit, &(nilfs)->ns_flags); \
212} \
213static inline int nilfs_##name(struct the_nilfs *nilfs) \
214{ \
215 return test_bit(THE_NILFS_##bit, &(nilfs)->ns_flags); \
216}
217
218THE_NILFS_FNS(INIT, init)
65b4643d 219THE_NILFS_FNS(DISCONTINUED, discontinued)
1cf58fa8 220THE_NILFS_FNS(GC_RUNNING, gc_running)
e605f0a7 221THE_NILFS_FNS(SB_DIRTY, sb_dirty)
65b4643d 222
3b2ce58b
RK
223/*
224 * Mount option operations
225 */
226#define nilfs_clear_opt(nilfs, opt) \
227 do { (nilfs)->ns_mount_opt &= ~NILFS_MOUNT_##opt; } while (0)
228#define nilfs_set_opt(nilfs, opt) \
229 do { (nilfs)->ns_mount_opt |= NILFS_MOUNT_##opt; } while (0)
230#define nilfs_test_opt(nilfs, opt) ((nilfs)->ns_mount_opt & NILFS_MOUNT_##opt)
231#define nilfs_write_opt(nilfs, mask, opt) \
232 do { (nilfs)->ns_mount_opt = \
233 (((nilfs)->ns_mount_opt & ~NILFS_MOUNT_##mask) | \
234 NILFS_MOUNT_##opt); \
235 } while (0)
236
ba65ae47
RK
237/**
238 * struct nilfs_root - nilfs root object
239 * @cno: checkpoint number
240 * @rb_node: red-black tree node
241 * @count: refcount of this structure
242 * @nilfs: nilfs object
243 * @ifile: inode file
ba65ae47 244 * @inodes_count: number of inodes
f5974c8f 245 * @blocks_count: number of blocks
a5a7332a
VD
246 * @snapshot_kobj: /sys/fs/<nilfs>/<device>/mounted_snapshots/<snapshot>
247 * @snapshot_kobj_unregister: completion state for kernel object
ba65ae47
RK
248 */
249struct nilfs_root {
250 __u64 cno;
251 struct rb_node rb_node;
252
253 atomic_t count;
254 struct the_nilfs *nilfs;
255 struct inode *ifile;
256
e5f7f848
VD
257 atomic64_t inodes_count;
258 atomic64_t blocks_count;
a5a7332a
VD
259
260 /* /sys/fs/<nilfs>/<device>/mounted_snapshots/<snapshot> */
261 struct kobject snapshot_kobj;
262 struct completion snapshot_kobj_unregister;
ba65ae47
RK
263};
264
265/* Special checkpoint number */
266#define NILFS_CPTREE_CURRENT_CNO 0
267
e339ad31
RK
268/* Minimum interval of periodical update of superblocks (in seconds) */
269#define NILFS_SB_FREQ 10
e339ad31 270
79efdd94
JS
271static inline int nilfs_sb_need_update(struct the_nilfs *nilfs)
272{
273 u64 t = get_seconds();
caa05d49
VD
274 return t < nilfs->ns_sbwtime ||
275 t > nilfs->ns_sbwtime + nilfs->ns_sb_update_freq;
79efdd94
JS
276}
277
b2ac86e1 278static inline int nilfs_sb_will_flip(struct the_nilfs *nilfs)
79efdd94 279{
b2ac86e1
JS
280 int flip_bits = nilfs->ns_sbwcount & 0x0FL;
281 return (flip_bits != 0x08 && flip_bits != 0x0F);
79efdd94
JS
282}
283
65b4643d 284void nilfs_set_last_segment(struct the_nilfs *, sector_t, u64, __u64);
348fe8da
RK
285struct the_nilfs *alloc_nilfs(struct block_device *bdev);
286void destroy_nilfs(struct the_nilfs *nilfs);
f7545144
RK
287int init_nilfs(struct the_nilfs *nilfs, struct super_block *sb, char *data);
288int load_nilfs(struct the_nilfs *nilfs, struct super_block *sb);
4e33f9ea
RK
289unsigned long nilfs_nrsvsegs(struct the_nilfs *nilfs, unsigned long nsegs);
290void nilfs_set_nsegments(struct the_nilfs *nilfs, unsigned long nsegs);
e902ec99 291int nilfs_discard_segments(struct the_nilfs *, __u64 *, size_t);
65b4643d 292int nilfs_count_free_blocks(struct the_nilfs *, sector_t *);
ba65ae47
RK
293struct nilfs_root *nilfs_lookup_root(struct the_nilfs *nilfs, __u64 cno);
294struct nilfs_root *nilfs_find_or_create_root(struct the_nilfs *nilfs,
295 __u64 cno);
296void nilfs_put_root(struct nilfs_root *root);
65b4643d 297int nilfs_near_disk_full(struct the_nilfs *);
e339ad31
RK
298void nilfs_fall_back_super_block(struct the_nilfs *);
299void nilfs_swap_super_block(struct the_nilfs *);
65b4643d
RK
300
301
ba65ae47
RK
302static inline void nilfs_get_root(struct nilfs_root *root)
303{
304 atomic_inc(&root->count);
305}
306
a057d2c0
RK
307static inline int nilfs_valid_fs(struct the_nilfs *nilfs)
308{
309 unsigned valid_fs;
310
311 down_read(&nilfs->ns_sem);
312 valid_fs = (nilfs->ns_mount_state & NILFS_VALID_FS);
313 up_read(&nilfs->ns_sem);
314 return valid_fs;
315}
316
65b4643d
RK
317static inline void
318nilfs_get_segment_range(struct the_nilfs *nilfs, __u64 segnum,
319 sector_t *seg_start, sector_t *seg_end)
320{
321 *seg_start = (sector_t)nilfs->ns_blocks_per_segment * segnum;
322 *seg_end = *seg_start + nilfs->ns_blocks_per_segment - 1;
323 if (segnum == 0)
324 *seg_start = nilfs->ns_first_data_block;
325}
326
327static inline sector_t
328nilfs_get_segment_start_blocknr(struct the_nilfs *nilfs, __u64 segnum)
329{
330 return (segnum == 0) ? nilfs->ns_first_data_block :
331 (sector_t)nilfs->ns_blocks_per_segment * segnum;
332}
333
334static inline __u64
335nilfs_get_segnum_of_block(struct the_nilfs *nilfs, sector_t blocknr)
336{
337 sector_t segnum = blocknr;
338
339 sector_div(segnum, nilfs->ns_blocks_per_segment);
340 return segnum;
341}
342
343static inline void
344nilfs_terminate_segment(struct the_nilfs *nilfs, sector_t seg_start,
345 sector_t seg_end)
346{
347 /* terminate the current full segment (used in case of I/O-error) */
348 nilfs->ns_pseg_offset = seg_end - seg_start + 1;
349}
350
351static inline void nilfs_shift_to_next_segment(struct the_nilfs *nilfs)
352{
353 /* move forward with a full segment */
354 nilfs->ns_segnum = nilfs->ns_nextnum;
355 nilfs->ns_pseg_offset = 0;
356 nilfs->ns_seg_seq++;
357}
358
359static inline __u64 nilfs_last_cno(struct the_nilfs *nilfs)
360{
361 __u64 cno;
362
363 spin_lock(&nilfs->ns_last_segment_lock);
364 cno = nilfs->ns_last_cno;
365 spin_unlock(&nilfs->ns_last_segment_lock);
366 return cno;
367}
368
cece5520
RK
369static inline int nilfs_segment_is_active(struct the_nilfs *nilfs, __u64 n)
370{
371 return n == nilfs->ns_segnum || n == nilfs->ns_nextnum;
372}
373
65b4643d 374#endif /* _THE_NILFS_H */