2 * the_nilfs.c - the_nilfs shared structure.
4 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
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.
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.
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
20 * Written by Ryusuke Konishi <ryusuke@osrg.net>
24 #include <linux/buffer_head.h>
25 #include <linux/slab.h>
26 #include <linux/blkdev.h>
27 #include <linux/backing-dev.h>
28 #include <linux/random.h>
29 #include <linux/crc32.h>
39 static int nilfs_valid_sb(struct nilfs_super_block
*sbp
);
41 void nilfs_set_last_segment(struct the_nilfs
*nilfs
,
42 sector_t start_blocknr
, u64 seq
, __u64 cno
)
44 spin_lock(&nilfs
->ns_last_segment_lock
);
45 nilfs
->ns_last_pseg
= start_blocknr
;
46 nilfs
->ns_last_seq
= seq
;
47 nilfs
->ns_last_cno
= cno
;
49 if (!nilfs_sb_dirty(nilfs
)) {
50 if (nilfs
->ns_prev_seq
== nilfs
->ns_last_seq
)
53 set_nilfs_sb_dirty(nilfs
);
55 nilfs
->ns_prev_seq
= nilfs
->ns_last_seq
;
58 spin_unlock(&nilfs
->ns_last_segment_lock
);
62 * alloc_nilfs - allocate a nilfs object
63 * @bdev: block device to which the_nilfs is related
65 * Return Value: On success, pointer to the_nilfs is returned.
66 * On error, NULL is returned.
68 struct the_nilfs
*alloc_nilfs(struct block_device
*bdev
)
70 struct the_nilfs
*nilfs
;
72 nilfs
= kzalloc(sizeof(*nilfs
), GFP_KERNEL
);
76 nilfs
->ns_bdev
= bdev
;
77 atomic_set(&nilfs
->ns_ndirtyblks
, 0);
78 init_rwsem(&nilfs
->ns_sem
);
79 mutex_init(&nilfs
->ns_snapshot_mount_mutex
);
80 INIT_LIST_HEAD(&nilfs
->ns_dirty_files
);
81 INIT_LIST_HEAD(&nilfs
->ns_gc_inodes
);
82 spin_lock_init(&nilfs
->ns_inode_lock
);
83 spin_lock_init(&nilfs
->ns_next_gen_lock
);
84 spin_lock_init(&nilfs
->ns_last_segment_lock
);
85 nilfs
->ns_cptree
= RB_ROOT
;
86 spin_lock_init(&nilfs
->ns_cptree_lock
);
87 init_rwsem(&nilfs
->ns_segctor_sem
);
88 nilfs
->ns_sb_update_freq
= NILFS_SB_FREQ
;
94 * destroy_nilfs - destroy nilfs object
95 * @nilfs: nilfs object to be released
97 void destroy_nilfs(struct the_nilfs
*nilfs
)
100 if (nilfs_init(nilfs
)) {
101 brelse(nilfs
->ns_sbh
[0]);
102 brelse(nilfs
->ns_sbh
[1]);
107 static int nilfs_load_super_root(struct the_nilfs
*nilfs
,
108 struct super_block
*sb
, sector_t sr_block
)
110 struct buffer_head
*bh_sr
;
111 struct nilfs_super_root
*raw_sr
;
112 struct nilfs_super_block
**sbp
= nilfs
->ns_sbp
;
113 struct nilfs_inode
*rawi
;
114 unsigned dat_entry_size
, segment_usage_size
, checkpoint_size
;
118 err
= nilfs_read_super_root_block(nilfs
, sr_block
, &bh_sr
, 1);
122 down_read(&nilfs
->ns_sem
);
123 dat_entry_size
= le16_to_cpu(sbp
[0]->s_dat_entry_size
);
124 checkpoint_size
= le16_to_cpu(sbp
[0]->s_checkpoint_size
);
125 segment_usage_size
= le16_to_cpu(sbp
[0]->s_segment_usage_size
);
126 up_read(&nilfs
->ns_sem
);
128 inode_size
= nilfs
->ns_inode_size
;
130 rawi
= (void *)bh_sr
->b_data
+ NILFS_SR_DAT_OFFSET(inode_size
);
131 err
= nilfs_dat_read(sb
, dat_entry_size
, rawi
, &nilfs
->ns_dat
);
135 rawi
= (void *)bh_sr
->b_data
+ NILFS_SR_CPFILE_OFFSET(inode_size
);
136 err
= nilfs_cpfile_read(sb
, checkpoint_size
, rawi
, &nilfs
->ns_cpfile
);
140 rawi
= (void *)bh_sr
->b_data
+ NILFS_SR_SUFILE_OFFSET(inode_size
);
141 err
= nilfs_sufile_read(sb
, segment_usage_size
, rawi
,
146 raw_sr
= (struct nilfs_super_root
*)bh_sr
->b_data
;
147 nilfs
->ns_nongc_ctime
= le64_to_cpu(raw_sr
->sr_nongc_ctime
);
154 iput(nilfs
->ns_cpfile
);
161 static void nilfs_init_recovery_info(struct nilfs_recovery_info
*ri
)
163 memset(ri
, 0, sizeof(*ri
));
164 INIT_LIST_HEAD(&ri
->ri_used_segments
);
167 static void nilfs_clear_recovery_info(struct nilfs_recovery_info
*ri
)
169 nilfs_dispose_segment_list(&ri
->ri_used_segments
);
173 * nilfs_store_log_cursor - load log cursor from a super block
174 * @nilfs: nilfs object
175 * @sbp: buffer storing super block to be read
177 * nilfs_store_log_cursor() reads the last position of the log
178 * containing a super root from a given super block, and initializes
179 * relevant information on the nilfs object preparatory for log
180 * scanning and recovery.
182 static int nilfs_store_log_cursor(struct the_nilfs
*nilfs
,
183 struct nilfs_super_block
*sbp
)
187 nilfs
->ns_last_pseg
= le64_to_cpu(sbp
->s_last_pseg
);
188 nilfs
->ns_last_cno
= le64_to_cpu(sbp
->s_last_cno
);
189 nilfs
->ns_last_seq
= le64_to_cpu(sbp
->s_last_seq
);
191 nilfs
->ns_prev_seq
= nilfs
->ns_last_seq
;
192 nilfs
->ns_seg_seq
= nilfs
->ns_last_seq
;
194 nilfs_get_segnum_of_block(nilfs
, nilfs
->ns_last_pseg
);
195 nilfs
->ns_cno
= nilfs
->ns_last_cno
+ 1;
196 if (nilfs
->ns_segnum
>= nilfs
->ns_nsegments
) {
197 printk(KERN_ERR
"NILFS invalid last segment number.\n");
204 * load_nilfs - load and recover the nilfs
205 * @nilfs: the_nilfs structure to be released
206 * @sb: super block isntance used to recover past segment
208 * load_nilfs() searches and load the latest super root,
209 * attaches the last segment, and does recovery if needed.
210 * The caller must call this exclusively for simultaneous mounts.
212 int load_nilfs(struct the_nilfs
*nilfs
, struct super_block
*sb
)
214 struct nilfs_recovery_info ri
;
215 unsigned int s_flags
= sb
->s_flags
;
216 int really_read_only
= bdev_read_only(nilfs
->ns_bdev
);
217 int valid_fs
= nilfs_valid_fs(nilfs
);
221 printk(KERN_WARNING
"NILFS warning: mounting unchecked fs\n");
222 if (s_flags
& MS_RDONLY
) {
223 printk(KERN_INFO
"NILFS: INFO: recovery "
224 "required for readonly filesystem.\n");
225 printk(KERN_INFO
"NILFS: write access will "
226 "be enabled during recovery.\n");
230 nilfs_init_recovery_info(&ri
);
232 err
= nilfs_search_super_root(nilfs
, &ri
);
234 struct nilfs_super_block
**sbp
= nilfs
->ns_sbp
;
240 if (!nilfs_valid_sb(sbp
[1])) {
242 "NILFS warning: unable to fall back to spare"
247 "NILFS: try rollback from an earlier position\n");
250 * restore super block with its spare and reconfigure
251 * relevant states of the nilfs object.
253 memcpy(sbp
[0], sbp
[1], nilfs
->ns_sbsize
);
254 nilfs
->ns_crc_seed
= le32_to_cpu(sbp
[0]->s_crc_seed
);
255 nilfs
->ns_sbwtime
= le64_to_cpu(sbp
[0]->s_wtime
);
257 /* verify consistency between two super blocks */
258 blocksize
= BLOCK_SIZE
<< le32_to_cpu(sbp
[0]->s_log_block_size
);
259 if (blocksize
!= nilfs
->ns_blocksize
) {
261 "NILFS warning: blocksize differs between "
262 "two super blocks (%d != %d)\n",
263 blocksize
, nilfs
->ns_blocksize
);
267 err
= nilfs_store_log_cursor(nilfs
, sbp
[0]);
271 /* drop clean flag to allow roll-forward and recovery */
272 nilfs
->ns_mount_state
&= ~NILFS_VALID_FS
;
275 err
= nilfs_search_super_root(nilfs
, &ri
);
280 err
= nilfs_load_super_root(nilfs
, sb
, ri
.ri_super_root
);
282 printk(KERN_ERR
"NILFS: error loading super root.\n");
289 if (s_flags
& MS_RDONLY
) {
292 if (nilfs_test_opt(nilfs
, NORECOVERY
)) {
293 printk(KERN_INFO
"NILFS: norecovery option specified. "
294 "skipping roll-forward recovery\n");
297 features
= le64_to_cpu(nilfs
->ns_sbp
[0]->s_feature_compat_ro
) &
298 ~NILFS_FEATURE_COMPAT_RO_SUPP
;
300 printk(KERN_ERR
"NILFS: couldn't proceed with "
301 "recovery because of unsupported optional "
303 (unsigned long long)features
);
307 if (really_read_only
) {
308 printk(KERN_ERR
"NILFS: write access "
309 "unavailable, cannot proceed.\n");
313 sb
->s_flags
&= ~MS_RDONLY
;
314 } else if (nilfs_test_opt(nilfs
, NORECOVERY
)) {
315 printk(KERN_ERR
"NILFS: recovery cancelled because norecovery "
316 "option was specified for a read/write mount\n");
321 err
= nilfs_salvage_orphan_logs(nilfs
, sb
, &ri
);
325 down_write(&nilfs
->ns_sem
);
326 nilfs
->ns_mount_state
|= NILFS_VALID_FS
; /* set "clean" flag */
327 err
= nilfs_cleanup_super(sb
);
328 up_write(&nilfs
->ns_sem
);
331 printk(KERN_ERR
"NILFS: failed to update super block. "
332 "recovery unfinished.\n");
335 printk(KERN_INFO
"NILFS: recovery complete.\n");
338 nilfs_clear_recovery_info(&ri
);
339 sb
->s_flags
= s_flags
;
343 printk(KERN_ERR
"NILFS: error searching super root.\n");
347 iput(nilfs
->ns_cpfile
);
348 iput(nilfs
->ns_sufile
);
352 nilfs_clear_recovery_info(&ri
);
353 sb
->s_flags
= s_flags
;
357 static unsigned long long nilfs_max_size(unsigned int blkbits
)
359 unsigned int max_bits
;
360 unsigned long long res
= MAX_LFS_FILESIZE
; /* page cache limit */
362 max_bits
= blkbits
+ NILFS_BMAP_KEY_BIT
; /* bmap size limit */
364 res
= min_t(unsigned long long, res
, (1ULL << max_bits
) - 1);
369 * nilfs_nrsvsegs - calculate the number of reserved segments
370 * @nilfs: nilfs object
371 * @nsegs: total number of segments
373 unsigned long nilfs_nrsvsegs(struct the_nilfs
*nilfs
, unsigned long nsegs
)
375 return max_t(unsigned long, NILFS_MIN_NRSVSEGS
,
376 DIV_ROUND_UP(nsegs
* nilfs
->ns_r_segments_percentage
,
380 void nilfs_set_nsegments(struct the_nilfs
*nilfs
, unsigned long nsegs
)
382 nilfs
->ns_nsegments
= nsegs
;
383 nilfs
->ns_nrsvsegs
= nilfs_nrsvsegs(nilfs
, nsegs
);
386 static int nilfs_store_disk_layout(struct the_nilfs
*nilfs
,
387 struct nilfs_super_block
*sbp
)
389 if (le32_to_cpu(sbp
->s_rev_level
) < NILFS_MIN_SUPP_REV
) {
390 printk(KERN_ERR
"NILFS: unsupported revision "
391 "(superblock rev.=%d.%d, current rev.=%d.%d). "
392 "Please check the version of mkfs.nilfs.\n",
393 le32_to_cpu(sbp
->s_rev_level
),
394 le16_to_cpu(sbp
->s_minor_rev_level
),
395 NILFS_CURRENT_REV
, NILFS_MINOR_REV
);
398 nilfs
->ns_sbsize
= le16_to_cpu(sbp
->s_bytes
);
399 if (nilfs
->ns_sbsize
> BLOCK_SIZE
)
402 nilfs
->ns_inode_size
= le16_to_cpu(sbp
->s_inode_size
);
403 if (nilfs
->ns_inode_size
> nilfs
->ns_blocksize
) {
404 printk(KERN_ERR
"NILFS: too large inode size: %d bytes.\n",
405 nilfs
->ns_inode_size
);
407 } else if (nilfs
->ns_inode_size
< NILFS_MIN_INODE_SIZE
) {
408 printk(KERN_ERR
"NILFS: too small inode size: %d bytes.\n",
409 nilfs
->ns_inode_size
);
413 nilfs
->ns_first_ino
= le32_to_cpu(sbp
->s_first_ino
);
415 nilfs
->ns_blocks_per_segment
= le32_to_cpu(sbp
->s_blocks_per_segment
);
416 if (nilfs
->ns_blocks_per_segment
< NILFS_SEG_MIN_BLOCKS
) {
417 printk(KERN_ERR
"NILFS: too short segment.\n");
421 nilfs
->ns_first_data_block
= le64_to_cpu(sbp
->s_first_data_block
);
422 nilfs
->ns_r_segments_percentage
=
423 le32_to_cpu(sbp
->s_r_segments_percentage
);
424 if (nilfs
->ns_r_segments_percentage
< 1 ||
425 nilfs
->ns_r_segments_percentage
> 99) {
426 printk(KERN_ERR
"NILFS: invalid reserved segments percentage.\n");
430 nilfs_set_nsegments(nilfs
, le64_to_cpu(sbp
->s_nsegments
));
431 nilfs
->ns_crc_seed
= le32_to_cpu(sbp
->s_crc_seed
);
435 static int nilfs_valid_sb(struct nilfs_super_block
*sbp
)
437 static unsigned char sum
[4];
438 const int sumoff
= offsetof(struct nilfs_super_block
, s_sum
);
442 if (!sbp
|| le16_to_cpu(sbp
->s_magic
) != NILFS_SUPER_MAGIC
)
444 bytes
= le16_to_cpu(sbp
->s_bytes
);
445 if (bytes
> BLOCK_SIZE
)
447 crc
= crc32_le(le32_to_cpu(sbp
->s_crc_seed
), (unsigned char *)sbp
,
449 crc
= crc32_le(crc
, sum
, 4);
450 crc
= crc32_le(crc
, (unsigned char *)sbp
+ sumoff
+ 4,
452 return crc
== le32_to_cpu(sbp
->s_sum
);
455 static int nilfs_sb2_bad_offset(struct nilfs_super_block
*sbp
, u64 offset
)
457 return offset
< ((le64_to_cpu(sbp
->s_nsegments
) *
458 le32_to_cpu(sbp
->s_blocks_per_segment
)) <<
459 (le32_to_cpu(sbp
->s_log_block_size
) + 10));
462 static void nilfs_release_super_block(struct the_nilfs
*nilfs
)
466 for (i
= 0; i
< 2; i
++) {
467 if (nilfs
->ns_sbp
[i
]) {
468 brelse(nilfs
->ns_sbh
[i
]);
469 nilfs
->ns_sbh
[i
] = NULL
;
470 nilfs
->ns_sbp
[i
] = NULL
;
475 void nilfs_fall_back_super_block(struct the_nilfs
*nilfs
)
477 brelse(nilfs
->ns_sbh
[0]);
478 nilfs
->ns_sbh
[0] = nilfs
->ns_sbh
[1];
479 nilfs
->ns_sbp
[0] = nilfs
->ns_sbp
[1];
480 nilfs
->ns_sbh
[1] = NULL
;
481 nilfs
->ns_sbp
[1] = NULL
;
484 void nilfs_swap_super_block(struct the_nilfs
*nilfs
)
486 struct buffer_head
*tsbh
= nilfs
->ns_sbh
[0];
487 struct nilfs_super_block
*tsbp
= nilfs
->ns_sbp
[0];
489 nilfs
->ns_sbh
[0] = nilfs
->ns_sbh
[1];
490 nilfs
->ns_sbp
[0] = nilfs
->ns_sbp
[1];
491 nilfs
->ns_sbh
[1] = tsbh
;
492 nilfs
->ns_sbp
[1] = tsbp
;
495 static int nilfs_load_super_block(struct the_nilfs
*nilfs
,
496 struct super_block
*sb
, int blocksize
,
497 struct nilfs_super_block
**sbpp
)
499 struct nilfs_super_block
**sbp
= nilfs
->ns_sbp
;
500 struct buffer_head
**sbh
= nilfs
->ns_sbh
;
501 u64 sb2off
= NILFS_SB2_OFFSET_BYTES(nilfs
->ns_bdev
->bd_inode
->i_size
);
502 int valid
[2], swp
= 0;
504 sbp
[0] = nilfs_read_super_block(sb
, NILFS_SB_OFFSET_BYTES
, blocksize
,
506 sbp
[1] = nilfs_read_super_block(sb
, sb2off
, blocksize
, &sbh
[1]);
510 printk(KERN_ERR
"NILFS: unable to read superblock\n");
514 "NILFS warning: unable to read primary superblock "
515 "(blocksize = %d)\n", blocksize
);
516 } else if (!sbp
[1]) {
518 "NILFS warning: unable to read secondary superblock "
519 "(blocksize = %d)\n", blocksize
);
523 * Compare two super blocks and set 1 in swp if the secondary
524 * super block is valid and newer. Otherwise, set 0 in swp.
526 valid
[0] = nilfs_valid_sb(sbp
[0]);
527 valid
[1] = nilfs_valid_sb(sbp
[1]);
528 swp
= valid
[1] && (!valid
[0] ||
529 le64_to_cpu(sbp
[1]->s_last_cno
) >
530 le64_to_cpu(sbp
[0]->s_last_cno
));
532 if (valid
[swp
] && nilfs_sb2_bad_offset(sbp
[swp
], sb2off
)) {
540 nilfs_release_super_block(nilfs
);
541 printk(KERN_ERR
"NILFS: Can't find nilfs on dev %s.\n",
547 printk(KERN_WARNING
"NILFS warning: broken superblock. "
548 "using spare superblock (blocksize = %d).\n", blocksize
);
550 nilfs_swap_super_block(nilfs
);
552 nilfs
->ns_sbwcount
= 0;
553 nilfs
->ns_sbwtime
= le64_to_cpu(sbp
[0]->s_wtime
);
554 nilfs
->ns_prot_seq
= le64_to_cpu(sbp
[valid
[1] & !swp
]->s_last_seq
);
560 * init_nilfs - initialize a NILFS instance.
561 * @nilfs: the_nilfs structure
563 * @data: mount options
565 * init_nilfs() performs common initialization per block device (e.g.
566 * reading the super block, getting disk layout information, initializing
567 * shared fields in the_nilfs).
569 * Return Value: On success, 0 is returned. On error, a negative error
572 int init_nilfs(struct the_nilfs
*nilfs
, struct super_block
*sb
, char *data
)
574 struct nilfs_super_block
*sbp
;
578 down_write(&nilfs
->ns_sem
);
580 blocksize
= sb_min_blocksize(sb
, NILFS_MIN_BLOCK_SIZE
);
582 printk(KERN_ERR
"NILFS: unable to set blocksize\n");
586 err
= nilfs_load_super_block(nilfs
, sb
, blocksize
, &sbp
);
590 err
= nilfs_store_magic_and_option(sb
, sbp
, data
);
594 err
= nilfs_check_feature_compatibility(sb
, sbp
);
598 blocksize
= BLOCK_SIZE
<< le32_to_cpu(sbp
->s_log_block_size
);
599 if (blocksize
< NILFS_MIN_BLOCK_SIZE
||
600 blocksize
> NILFS_MAX_BLOCK_SIZE
) {
601 printk(KERN_ERR
"NILFS: couldn't mount because of unsupported "
602 "filesystem blocksize %d\n", blocksize
);
606 if (sb
->s_blocksize
!= blocksize
) {
607 int hw_blocksize
= bdev_logical_block_size(sb
->s_bdev
);
609 if (blocksize
< hw_blocksize
) {
611 "NILFS: blocksize %d too small for device "
612 "(sector-size = %d).\n",
613 blocksize
, hw_blocksize
);
617 nilfs_release_super_block(nilfs
);
618 sb_set_blocksize(sb
, blocksize
);
620 err
= nilfs_load_super_block(nilfs
, sb
, blocksize
, &sbp
);
623 /* not failed_sbh; sbh is released automatically
624 when reloading fails. */
626 nilfs
->ns_blocksize_bits
= sb
->s_blocksize_bits
;
627 nilfs
->ns_blocksize
= blocksize
;
629 get_random_bytes(&nilfs
->ns_next_generation
,
630 sizeof(nilfs
->ns_next_generation
));
632 err
= nilfs_store_disk_layout(nilfs
, sbp
);
636 sb
->s_maxbytes
= nilfs_max_size(sb
->s_blocksize_bits
);
638 nilfs
->ns_mount_state
= le16_to_cpu(sbp
->s_state
);
640 err
= nilfs_store_log_cursor(nilfs
, sbp
);
644 set_nilfs_init(nilfs
);
647 up_write(&nilfs
->ns_sem
);
651 nilfs_release_super_block(nilfs
);
655 int nilfs_discard_segments(struct the_nilfs
*nilfs
, __u64
*segnump
,
658 sector_t seg_start
, seg_end
;
659 sector_t start
= 0, nblocks
= 0;
660 unsigned int sects_per_block
;
664 sects_per_block
= (1 << nilfs
->ns_blocksize_bits
) /
665 bdev_logical_block_size(nilfs
->ns_bdev
);
666 for (sn
= segnump
; sn
< segnump
+ nsegs
; sn
++) {
667 nilfs_get_segment_range(nilfs
, *sn
, &seg_start
, &seg_end
);
671 nblocks
= seg_end
- seg_start
+ 1;
672 } else if (start
+ nblocks
== seg_start
) {
673 nblocks
+= seg_end
- seg_start
+ 1;
675 ret
= blkdev_issue_discard(nilfs
->ns_bdev
,
676 start
* sects_per_block
,
677 nblocks
* sects_per_block
,
685 ret
= blkdev_issue_discard(nilfs
->ns_bdev
,
686 start
* sects_per_block
,
687 nblocks
* sects_per_block
,
692 int nilfs_count_free_blocks(struct the_nilfs
*nilfs
, sector_t
*nblocks
)
694 unsigned long ncleansegs
;
696 down_read(&NILFS_MDT(nilfs
->ns_dat
)->mi_sem
);
697 ncleansegs
= nilfs_sufile_get_ncleansegs(nilfs
->ns_sufile
);
698 up_read(&NILFS_MDT(nilfs
->ns_dat
)->mi_sem
);
699 *nblocks
= (sector_t
)ncleansegs
* nilfs
->ns_blocks_per_segment
;
703 int nilfs_near_disk_full(struct the_nilfs
*nilfs
)
705 unsigned long ncleansegs
, nincsegs
;
707 ncleansegs
= nilfs_sufile_get_ncleansegs(nilfs
->ns_sufile
);
708 nincsegs
= atomic_read(&nilfs
->ns_ndirtyblks
) /
709 nilfs
->ns_blocks_per_segment
+ 1;
711 return ncleansegs
<= nilfs
->ns_nrsvsegs
+ nincsegs
;
714 struct nilfs_root
*nilfs_lookup_root(struct the_nilfs
*nilfs
, __u64 cno
)
717 struct nilfs_root
*root
;
719 spin_lock(&nilfs
->ns_cptree_lock
);
720 n
= nilfs
->ns_cptree
.rb_node
;
722 root
= rb_entry(n
, struct nilfs_root
, rb_node
);
724 if (cno
< root
->cno
) {
726 } else if (cno
> root
->cno
) {
729 atomic_inc(&root
->count
);
730 spin_unlock(&nilfs
->ns_cptree_lock
);
734 spin_unlock(&nilfs
->ns_cptree_lock
);
740 nilfs_find_or_create_root(struct the_nilfs
*nilfs
, __u64 cno
)
742 struct rb_node
**p
, *parent
;
743 struct nilfs_root
*root
, *new;
745 root
= nilfs_lookup_root(nilfs
, cno
);
749 new = kmalloc(sizeof(*root
), GFP_KERNEL
);
753 spin_lock(&nilfs
->ns_cptree_lock
);
755 p
= &nilfs
->ns_cptree
.rb_node
;
760 root
= rb_entry(parent
, struct nilfs_root
, rb_node
);
762 if (cno
< root
->cno
) {
764 } else if (cno
> root
->cno
) {
767 atomic_inc(&root
->count
);
768 spin_unlock(&nilfs
->ns_cptree_lock
);
777 atomic_set(&new->count
, 1);
778 atomic64_set(&new->inodes_count
, 0);
779 atomic64_set(&new->blocks_count
, 0);
781 rb_link_node(&new->rb_node
, parent
, p
);
782 rb_insert_color(&new->rb_node
, &nilfs
->ns_cptree
);
784 spin_unlock(&nilfs
->ns_cptree_lock
);
789 void nilfs_put_root(struct nilfs_root
*root
)
791 if (atomic_dec_and_test(&root
->count
)) {
792 struct the_nilfs
*nilfs
= root
->nilfs
;
794 spin_lock(&nilfs
->ns_cptree_lock
);
795 rb_erase(&root
->rb_node
, &nilfs
->ns_cptree
);
796 spin_unlock(&nilfs
->ns_cptree_lock
);