1 /*
2  * nilfs2_fs.h - NILFS2 on-disk structures and common declarations.
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 Lesser General Public License as published
8  * by the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser 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 Koji Sato <koji@osrg.net>
21  *            Ryusuke Konishi <ryusuke@osrg.net>
22  */
23 /*
24  *  linux/include/linux/ext2_fs.h
25  *
26  * Copyright (C) 1992, 1993, 1994, 1995
27  * Remy Card (card@masi.ibp.fr)
28  * Laboratoire MASI - Institut Blaise Pascal
29  * Universite Pierre et Marie Curie (Paris VI)
30  *
31  *  from
32  *
33  *  linux/include/linux/minix_fs.h
34  *
35  *  Copyright (C) 1991, 1992  Linus Torvalds
36  */
37 
38 #ifndef _LINUX_NILFS_FS_H
39 #define _LINUX_NILFS_FS_H
40 
41 #include <linux/types.h>
42 #include <linux/ioctl.h>
43 #include <linux/magic.h>
44 
45 
46 #define NILFS_INODE_BMAP_SIZE	7
47 /**
48  * struct nilfs_inode - structure of an inode on disk
49  * @i_blocks: blocks count
50  * @i_size: size in bytes
51  * @i_ctime: creation time (seconds)
52  * @i_mtime: modification time (seconds)
53  * @i_ctime_nsec: creation time (nano seconds)
54  * @i_mtime_nsec: modification time (nano seconds)
55  * @i_uid: user id
56  * @i_gid: group id
57  * @i_mode: file mode
58  * @i_links_count: links count
59  * @i_flags: file flags
60  * @i_bmap: block mapping
61  * @i_xattr: extended attributes
62  * @i_generation: file generation (for NFS)
63  * @i_pad:	padding
64  */
65 struct nilfs_inode {
66 	__le64	i_blocks;
67 	__le64	i_size;
68 	__le64	i_ctime;
69 	__le64	i_mtime;
70 	__le32	i_ctime_nsec;
71 	__le32	i_mtime_nsec;
72 	__le32	i_uid;
73 	__le32	i_gid;
74 	__le16	i_mode;
75 	__le16	i_links_count;
76 	__le32	i_flags;
77 	__le64	i_bmap[NILFS_INODE_BMAP_SIZE];
78 #define i_device_code	i_bmap[0]
79 	__le64	i_xattr;
80 	__le32	i_generation;
81 	__le32	i_pad;
82 };
83 
84 /**
85  * struct nilfs_super_root - structure of super root
86  * @sr_sum: check sum
87  * @sr_bytes: byte count of the structure
88  * @sr_flags: flags (reserved)
89  * @sr_nongc_ctime: write time of the last segment not for cleaner operation
90  * @sr_dat: DAT file inode
91  * @sr_cpfile: checkpoint file inode
92  * @sr_sufile: segment usage file inode
93  */
94 struct nilfs_super_root {
95 	__le32 sr_sum;
96 	__le16 sr_bytes;
97 	__le16 sr_flags;
98 	__le64 sr_nongc_ctime;
99 	struct nilfs_inode sr_dat;
100 	struct nilfs_inode sr_cpfile;
101 	struct nilfs_inode sr_sufile;
102 };
103 
104 #define NILFS_SR_MDT_OFFSET(inode_size, i)  \
105 	((unsigned long)&((struct nilfs_super_root *)0)->sr_dat + \
106 			(inode_size) * (i))
107 #define NILFS_SR_DAT_OFFSET(inode_size)     NILFS_SR_MDT_OFFSET(inode_size, 0)
108 #define NILFS_SR_CPFILE_OFFSET(inode_size)  NILFS_SR_MDT_OFFSET(inode_size, 1)
109 #define NILFS_SR_SUFILE_OFFSET(inode_size)  NILFS_SR_MDT_OFFSET(inode_size, 2)
110 #define NILFS_SR_BYTES                  (sizeof(struct nilfs_super_root))
111 
112 /*
113  * Maximal mount counts
114  */
115 #define NILFS_DFL_MAX_MNT_COUNT		50      /* 50 mounts */
116 
117 /*
118  * File system states (sbp->s_state, nilfs->ns_mount_state)
119  */
120 #define NILFS_VALID_FS			0x0001  /* Unmounted cleanly */
121 #define NILFS_ERROR_FS			0x0002  /* Errors detected */
122 #define NILFS_RESIZE_FS			0x0004	/* Resize required */
123 
124 /*
125  * Mount flags (sbi->s_mount_opt)
126  */
127 #define NILFS_MOUNT_ERROR_MODE		0x0070  /* Error mode mask */
128 #define NILFS_MOUNT_ERRORS_CONT		0x0010  /* Continue on errors */
129 #define NILFS_MOUNT_ERRORS_RO		0x0020  /* Remount fs ro on errors */
130 #define NILFS_MOUNT_ERRORS_PANIC	0x0040  /* Panic on errors */
131 #define NILFS_MOUNT_BARRIER		0x1000  /* Use block barriers */
132 #define NILFS_MOUNT_STRICT_ORDER	0x2000  /* Apply strict in-order
133 						   semantics also for data */
134 #define NILFS_MOUNT_NORECOVERY		0x4000  /* Disable write access during
135 						   mount-time recovery */
136 #define NILFS_MOUNT_DISCARD		0x8000  /* Issue DISCARD requests */
137 
138 
139 /**
140  * struct nilfs_super_block - structure of super block on disk
141  */
142 struct nilfs_super_block {
143 /*00*/	__le32	s_rev_level;		/* Revision level */
144 	__le16	s_minor_rev_level;	/* minor revision level */
145 	__le16	s_magic;		/* Magic signature */
146 
147 	__le16  s_bytes;		/* Bytes count of CRC calculation
148 					   for this structure. s_reserved
149 					   is excluded. */
150 	__le16  s_flags;		/* flags */
151 	__le32  s_crc_seed;		/* Seed value of CRC calculation */
152 /*10*/	__le32	s_sum;			/* Check sum of super block */
153 
154 	__le32	s_log_block_size;	/* Block size represented as follows
155 					   blocksize =
156 					       1 << (s_log_block_size + 10) */
157 	__le64  s_nsegments;		/* Number of segments in filesystem */
158 /*20*/	__le64  s_dev_size;		/* block device size in bytes */
159 	__le64	s_first_data_block;	/* 1st seg disk block number */
160 /*30*/	__le32  s_blocks_per_segment;   /* number of blocks per full segment */
161 	__le32	s_r_segments_percentage; /* Reserved segments percentage */
162 
163 	__le64  s_last_cno;		/* Last checkpoint number */
164 /*40*/	__le64  s_last_pseg;		/* disk block addr pseg written last */
165 	__le64  s_last_seq;             /* seq. number of seg written last */
166 /*50*/	__le64	s_free_blocks_count;	/* Free blocks count */
167 
168 	__le64	s_ctime;		/* Creation time (execution time of
169 					   newfs) */
170 /*60*/	__le64	s_mtime;		/* Mount time */
171 	__le64	s_wtime;		/* Write time */
172 /*70*/	__le16	s_mnt_count;		/* Mount count */
173 	__le16	s_max_mnt_count;	/* Maximal mount count */
174 	__le16	s_state;		/* File system state */
175 	__le16	s_errors;		/* Behaviour when detecting errors */
176 	__le64	s_lastcheck;		/* time of last check */
177 
178 /*80*/	__le32	s_checkinterval;	/* max. time between checks */
179 	__le32	s_creator_os;		/* OS */
180 	__le16	s_def_resuid;		/* Default uid for reserved blocks */
181 	__le16	s_def_resgid;		/* Default gid for reserved blocks */
182 	__le32	s_first_ino;		/* First non-reserved inode */
183 
184 /*90*/	__le16  s_inode_size;		/* Size of an inode */
185 	__le16  s_dat_entry_size;       /* Size of a dat entry */
186 	__le16  s_checkpoint_size;      /* Size of a checkpoint */
187 	__le16	s_segment_usage_size;	/* Size of a segment usage */
188 
189 /*98*/	__u8	s_uuid[16];		/* 128-bit uuid for volume */
190 /*A8*/	char	s_volume_name[80];	/* volume name */
191 
192 /*F8*/	__le32  s_c_interval;           /* Commit interval of segment */
193 	__le32  s_c_block_max;          /* Threshold of data amount for
194 					   the segment construction */
195 /*100*/	__le64  s_feature_compat;	/* Compatible feature set */
196 	__le64  s_feature_compat_ro;	/* Read-only compatible feature set */
197 	__le64  s_feature_incompat;	/* Incompatible feature set */
198 	__u32	s_reserved[186];	/* padding to the end of the block */
199 };
200 
201 /*
202  * Codes for operating systems
203  */
204 #define NILFS_OS_LINUX		0
205 /* Codes from 1 to 4 are reserved to keep compatibility with ext2 creator-OS */
206 
207 /*
208  * Revision levels
209  */
210 #define NILFS_CURRENT_REV	2	/* current major revision */
211 #define NILFS_MINOR_REV		0	/* minor revision */
212 #define NILFS_MIN_SUPP_REV	2	/* minimum supported revision */
213 
214 /*
215  * Feature set definitions
216  *
217  * If there is a bit set in the incompatible feature set that the kernel
218  * doesn't know about, it should refuse to mount the filesystem.
219  */
220 #define NILFS_FEATURE_COMPAT_RO_BLOCK_COUNT	0x00000001ULL
221 
222 #define NILFS_FEATURE_COMPAT_SUPP	0ULL
223 #define NILFS_FEATURE_COMPAT_RO_SUPP	NILFS_FEATURE_COMPAT_RO_BLOCK_COUNT
224 #define NILFS_FEATURE_INCOMPAT_SUPP	0ULL
225 
226 /*
227  * Bytes count of super_block for CRC-calculation
228  */
229 #define NILFS_SB_BYTES  \
230 	((long)&((struct nilfs_super_block *)0)->s_reserved)
231 
232 /*
233  * Special inode number
234  */
235 #define NILFS_ROOT_INO		2	/* Root file inode */
236 #define NILFS_DAT_INO		3	/* DAT file */
237 #define NILFS_CPFILE_INO	4	/* checkpoint file */
238 #define NILFS_SUFILE_INO	5	/* segment usage file */
239 #define NILFS_IFILE_INO		6	/* ifile */
240 #define NILFS_ATIME_INO		7	/* Atime file (reserved) */
241 #define NILFS_XATTR_INO		8	/* Xattribute file (reserved) */
242 #define NILFS_SKETCH_INO	10	/* Sketch file */
243 #define NILFS_USER_INO		11	/* Fisrt user's file inode number */
244 
245 #define NILFS_SB_OFFSET_BYTES	1024	/* byte offset of nilfs superblock */
246 
247 #define NILFS_SEG_MIN_BLOCKS	16	/* Minimum number of blocks in
248 					   a full segment */
249 #define NILFS_PSEG_MIN_BLOCKS	2	/* Minimum number of blocks in
250 					   a partial segment */
251 #define NILFS_MIN_NRSVSEGS	8	/* Minimum number of reserved
252 					   segments */
253 
254 /*
255  * We call DAT, cpfile, and sufile root metadata files.  Inodes of
256  * these files are written in super root block instead of ifile, and
257  * garbage collector doesn't keep any past versions of these files.
258  */
259 #define NILFS_ROOT_METADATA_FILE(ino) \
260 	((ino) >= NILFS_DAT_INO && (ino) <= NILFS_SUFILE_INO)
261 
262 /*
263  * bytes offset of secondary super block
264  */
265 #define NILFS_SB2_OFFSET_BYTES(devsize)	((((devsize) >> 12) - 1) << 12)
266 
267 /*
268  * Maximal count of links to a file
269  */
270 #define NILFS_LINK_MAX		32000
271 
272 /*
273  * Structure of a directory entry
274  *  (Same as ext2)
275  */
276 
277 #define NILFS_NAME_LEN 255
278 
279 /*
280  * Block size limitations
281  */
282 #define NILFS_MIN_BLOCK_SIZE		1024
283 #define NILFS_MAX_BLOCK_SIZE		65536
284 
285 /*
286  * The new version of the directory entry.  Since V0 structures are
287  * stored in intel byte order, and the name_len field could never be
288  * bigger than 255 chars, it's safe to reclaim the extra byte for the
289  * file_type field.
290  */
291 struct nilfs_dir_entry {
292 	__le64	inode;			/* Inode number */
293 	__le16	rec_len;		/* Directory entry length */
294 	__u8	name_len;		/* Name length */
295 	__u8	file_type;
296 	char	name[NILFS_NAME_LEN];	/* File name */
297 	char    pad;
298 };
299 
300 /*
301  * NILFS directory file types.  Only the low 3 bits are used.  The
302  * other bits are reserved for now.
303  */
304 enum {
305 	NILFS_FT_UNKNOWN,
306 	NILFS_FT_REG_FILE,
307 	NILFS_FT_DIR,
308 	NILFS_FT_CHRDEV,
309 	NILFS_FT_BLKDEV,
310 	NILFS_FT_FIFO,
311 	NILFS_FT_SOCK,
312 	NILFS_FT_SYMLINK,
313 	NILFS_FT_MAX
314 };
315 
316 /*
317  * NILFS_DIR_PAD defines the directory entries boundaries
318  *
319  * NOTE: It must be a multiple of 8
320  */
321 #define NILFS_DIR_PAD			8
322 #define NILFS_DIR_ROUND			(NILFS_DIR_PAD - 1)
323 #define NILFS_DIR_REC_LEN(name_len)	(((name_len) + 12 + NILFS_DIR_ROUND) & \
324 					~NILFS_DIR_ROUND)
325 #define NILFS_MAX_REC_LEN		((1<<16)-1)
326 
nilfs_rec_len_from_disk(__le16 dlen)327 static inline unsigned nilfs_rec_len_from_disk(__le16 dlen)
328 {
329 	unsigned len = le16_to_cpu(dlen);
330 
331 #if !defined(__KERNEL__) || (PAGE_CACHE_SIZE >= 65536)
332 	if (len == NILFS_MAX_REC_LEN)
333 		return 1 << 16;
334 #endif
335 	return len;
336 }
337 
nilfs_rec_len_to_disk(unsigned len)338 static inline __le16 nilfs_rec_len_to_disk(unsigned len)
339 {
340 #if !defined(__KERNEL__) || (PAGE_CACHE_SIZE >= 65536)
341 	if (len == (1 << 16))
342 		return cpu_to_le16(NILFS_MAX_REC_LEN);
343 	else if (len > (1 << 16))
344 		BUG();
345 #endif
346 	return cpu_to_le16(len);
347 }
348 
349 /**
350  * struct nilfs_finfo - file information
351  * @fi_ino: inode number
352  * @fi_cno: checkpoint number
353  * @fi_nblocks: number of blocks (including intermediate blocks)
354  * @fi_ndatablk: number of file data blocks
355  */
356 struct nilfs_finfo {
357 	__le64 fi_ino;
358 	__le64 fi_cno;
359 	__le32 fi_nblocks;
360 	__le32 fi_ndatablk;
361 	/* array of virtual block numbers */
362 };
363 
364 /**
365  * struct nilfs_binfo_v - information for the block to which a virtual block number is assigned
366  * @bi_vblocknr: virtual block number
367  * @bi_blkoff: block offset
368  */
369 struct nilfs_binfo_v {
370 	__le64 bi_vblocknr;
371 	__le64 bi_blkoff;
372 };
373 
374 /**
375  * struct nilfs_binfo_dat - information for the block which belongs to the DAT file
376  * @bi_blkoff: block offset
377  * @bi_level: level
378  * @bi_pad: padding
379  */
380 struct nilfs_binfo_dat {
381 	__le64 bi_blkoff;
382 	__u8 bi_level;
383 	__u8 bi_pad[7];
384 };
385 
386 /**
387  * union nilfs_binfo: block information
388  * @bi_v: nilfs_binfo_v structure
389  * @bi_dat: nilfs_binfo_dat structure
390  */
391 union nilfs_binfo {
392 	struct nilfs_binfo_v bi_v;
393 	struct nilfs_binfo_dat bi_dat;
394 };
395 
396 /**
397  * struct nilfs_segment_summary - segment summary
398  * @ss_datasum: checksum of data
399  * @ss_sumsum: checksum of segment summary
400  * @ss_magic: magic number
401  * @ss_bytes: size of this structure in bytes
402  * @ss_flags: flags
403  * @ss_seq: sequence number
404  * @ss_create: creation timestamp
405  * @ss_next: next segment
406  * @ss_nblocks: number of blocks
407  * @ss_nfinfo: number of finfo structures
408  * @ss_sumbytes: total size of segment summary in bytes
409  * @ss_pad: padding
410  * @ss_cno: checkpoint number
411  */
412 struct nilfs_segment_summary {
413 	__le32 ss_datasum;
414 	__le32 ss_sumsum;
415 	__le32 ss_magic;
416 	__le16 ss_bytes;
417 	__le16 ss_flags;
418 	__le64 ss_seq;
419 	__le64 ss_create;
420 	__le64 ss_next;
421 	__le32 ss_nblocks;
422 	__le32 ss_nfinfo;
423 	__le32 ss_sumbytes;
424 	__le32 ss_pad;
425 	__le64 ss_cno;
426 	/* array of finfo structures */
427 };
428 
429 #define NILFS_SEGSUM_MAGIC	0x1eaffa11  /* segment summary magic number */
430 
431 /*
432  * Segment summary flags
433  */
434 #define NILFS_SS_LOGBGN 0x0001  /* begins a logical segment */
435 #define NILFS_SS_LOGEND 0x0002  /* ends a logical segment */
436 #define NILFS_SS_SR     0x0004  /* has super root */
437 #define NILFS_SS_SYNDT  0x0008  /* includes data only updates */
438 #define NILFS_SS_GC     0x0010  /* segment written for cleaner operation */
439 
440 /**
441  * struct nilfs_btree_node - B-tree node
442  * @bn_flags: flags
443  * @bn_level: level
444  * @bn_nchildren: number of children
445  * @bn_pad: padding
446  */
447 struct nilfs_btree_node {
448 	__u8 bn_flags;
449 	__u8 bn_level;
450 	__le16 bn_nchildren;
451 	__le32 bn_pad;
452 };
453 
454 /* flags */
455 #define NILFS_BTREE_NODE_ROOT   0x01
456 
457 /* level */
458 #define NILFS_BTREE_LEVEL_DATA          0
459 #define NILFS_BTREE_LEVEL_NODE_MIN      (NILFS_BTREE_LEVEL_DATA + 1)
460 #define NILFS_BTREE_LEVEL_MAX           14
461 
462 /**
463  * struct nilfs_palloc_group_desc - block group descriptor
464  * @pg_nfrees: number of free entries in block group
465  */
466 struct nilfs_palloc_group_desc {
467 	__le32 pg_nfrees;
468 };
469 
470 /**
471  * struct nilfs_dat_entry - disk address translation entry
472  * @de_blocknr: block number
473  * @de_start: start checkpoint number
474  * @de_end: end checkpoint number
475  * @de_rsv: reserved for future use
476  */
477 struct nilfs_dat_entry {
478 	__le64 de_blocknr;
479 	__le64 de_start;
480 	__le64 de_end;
481 	__le64 de_rsv;
482 };
483 
484 /**
485  * struct nilfs_snapshot_list - snapshot list
486  * @ssl_next: next checkpoint number on snapshot list
487  * @ssl_prev: previous checkpoint number on snapshot list
488  */
489 struct nilfs_snapshot_list {
490 	__le64 ssl_next;
491 	__le64 ssl_prev;
492 };
493 
494 /**
495  * struct nilfs_checkpoint - checkpoint structure
496  * @cp_flags: flags
497  * @cp_checkpoints_count: checkpoints count in a block
498  * @cp_snapshot_list: snapshot list
499  * @cp_cno: checkpoint number
500  * @cp_create: creation timestamp
501  * @cp_nblk_inc: number of blocks incremented by this checkpoint
502  * @cp_inodes_count: inodes count
503  * @cp_blocks_count: blocks count
504  * @cp_ifile_inode: inode of ifile
505  */
506 struct nilfs_checkpoint {
507 	__le32 cp_flags;
508 	__le32 cp_checkpoints_count;
509 	struct nilfs_snapshot_list cp_snapshot_list;
510 	__le64 cp_cno;
511 	__le64 cp_create;
512 	__le64 cp_nblk_inc;
513 	__le64 cp_inodes_count;
514 	__le64 cp_blocks_count;
515 
516 	/* Do not change the byte offset of ifile inode.
517 	   To keep the compatibility of the disk format,
518 	   additional fields should be added behind cp_ifile_inode. */
519 	struct nilfs_inode cp_ifile_inode;
520 };
521 
522 /* checkpoint flags */
523 enum {
524 	NILFS_CHECKPOINT_SNAPSHOT,
525 	NILFS_CHECKPOINT_INVALID,
526 	NILFS_CHECKPOINT_SKETCH,
527 	NILFS_CHECKPOINT_MINOR,
528 };
529 
530 #define NILFS_CHECKPOINT_FNS(flag, name)				\
531 static inline void							\
532 nilfs_checkpoint_set_##name(struct nilfs_checkpoint *cp)		\
533 {									\
534 	cp->cp_flags = cpu_to_le32(le32_to_cpu(cp->cp_flags) |		\
535 				   (1UL << NILFS_CHECKPOINT_##flag));	\
536 }									\
537 static inline void							\
538 nilfs_checkpoint_clear_##name(struct nilfs_checkpoint *cp)		\
539 {									\
540 	cp->cp_flags = cpu_to_le32(le32_to_cpu(cp->cp_flags) &		\
541 				   ~(1UL << NILFS_CHECKPOINT_##flag));	\
542 }									\
543 static inline int							\
544 nilfs_checkpoint_##name(const struct nilfs_checkpoint *cp)		\
545 {									\
546 	return !!(le32_to_cpu(cp->cp_flags) &				\
547 		  (1UL << NILFS_CHECKPOINT_##flag));			\
548 }
549 
550 NILFS_CHECKPOINT_FNS(SNAPSHOT, snapshot)
551 NILFS_CHECKPOINT_FNS(INVALID, invalid)
552 NILFS_CHECKPOINT_FNS(MINOR, minor)
553 
554 /**
555  * struct nilfs_cpinfo - checkpoint information
556  * @ci_flags: flags
557  * @ci_pad: padding
558  * @ci_cno: checkpoint number
559  * @ci_create: creation timestamp
560  * @ci_nblk_inc: number of blocks incremented by this checkpoint
561  * @ci_inodes_count: inodes count
562  * @ci_blocks_count: blocks count
563  * @ci_next: next checkpoint number in snapshot list
564  */
565 struct nilfs_cpinfo {
566 	__u32 ci_flags;
567 	__u32 ci_pad;
568 	__u64 ci_cno;
569 	__u64 ci_create;
570 	__u64 ci_nblk_inc;
571 	__u64 ci_inodes_count;
572 	__u64 ci_blocks_count;
573 	__u64 ci_next;
574 };
575 
576 #define NILFS_CPINFO_FNS(flag, name)					\
577 static inline int							\
578 nilfs_cpinfo_##name(const struct nilfs_cpinfo *cpinfo)			\
579 {									\
580 	return !!(cpinfo->ci_flags & (1UL << NILFS_CHECKPOINT_##flag));	\
581 }
582 
583 NILFS_CPINFO_FNS(SNAPSHOT, snapshot)
584 NILFS_CPINFO_FNS(INVALID, invalid)
585 NILFS_CPINFO_FNS(MINOR, minor)
586 
587 
588 /**
589  * struct nilfs_cpfile_header - checkpoint file header
590  * @ch_ncheckpoints: number of checkpoints
591  * @ch_nsnapshots: number of snapshots
592  * @ch_snapshot_list: snapshot list
593  */
594 struct nilfs_cpfile_header {
595 	__le64 ch_ncheckpoints;
596 	__le64 ch_nsnapshots;
597 	struct nilfs_snapshot_list ch_snapshot_list;
598 };
599 
600 #define NILFS_CPFILE_FIRST_CHECKPOINT_OFFSET	\
601 	((sizeof(struct nilfs_cpfile_header) +				\
602 	  sizeof(struct nilfs_checkpoint) - 1) /			\
603 			sizeof(struct nilfs_checkpoint))
604 
605 /**
606  * struct nilfs_segment_usage - segment usage
607  * @su_lastmod: last modified timestamp
608  * @su_nblocks: number of blocks in segment
609  * @su_flags: flags
610  */
611 struct nilfs_segment_usage {
612 	__le64 su_lastmod;
613 	__le32 su_nblocks;
614 	__le32 su_flags;
615 };
616 
617 /* segment usage flag */
618 enum {
619 	NILFS_SEGMENT_USAGE_ACTIVE,
620 	NILFS_SEGMENT_USAGE_DIRTY,
621 	NILFS_SEGMENT_USAGE_ERROR,
622 
623 	/* ... */
624 };
625 
626 #define NILFS_SEGMENT_USAGE_FNS(flag, name)				\
627 static inline void							\
628 nilfs_segment_usage_set_##name(struct nilfs_segment_usage *su)		\
629 {									\
630 	su->su_flags = cpu_to_le32(le32_to_cpu(su->su_flags) |		\
631 				   (1UL << NILFS_SEGMENT_USAGE_##flag));\
632 }									\
633 static inline void							\
634 nilfs_segment_usage_clear_##name(struct nilfs_segment_usage *su)	\
635 {									\
636 	su->su_flags =							\
637 		cpu_to_le32(le32_to_cpu(su->su_flags) &			\
638 			    ~(1UL << NILFS_SEGMENT_USAGE_##flag));      \
639 }									\
640 static inline int							\
641 nilfs_segment_usage_##name(const struct nilfs_segment_usage *su)	\
642 {									\
643 	return !!(le32_to_cpu(su->su_flags) &				\
644 		  (1UL << NILFS_SEGMENT_USAGE_##flag));			\
645 }
646 
NILFS_SEGMENT_USAGE_FNS(ACTIVE,active)647 NILFS_SEGMENT_USAGE_FNS(ACTIVE, active)
648 NILFS_SEGMENT_USAGE_FNS(DIRTY, dirty)
649 NILFS_SEGMENT_USAGE_FNS(ERROR, error)
650 
651 static inline void
652 nilfs_segment_usage_set_clean(struct nilfs_segment_usage *su)
653 {
654 	su->su_lastmod = cpu_to_le64(0);
655 	su->su_nblocks = cpu_to_le32(0);
656 	su->su_flags = cpu_to_le32(0);
657 }
658 
659 static inline int
nilfs_segment_usage_clean(const struct nilfs_segment_usage * su)660 nilfs_segment_usage_clean(const struct nilfs_segment_usage *su)
661 {
662 	return !le32_to_cpu(su->su_flags);
663 }
664 
665 /**
666  * struct nilfs_sufile_header - segment usage file header
667  * @sh_ncleansegs: number of clean segments
668  * @sh_ndirtysegs: number of dirty segments
669  * @sh_last_alloc: last allocated segment number
670  */
671 struct nilfs_sufile_header {
672 	__le64 sh_ncleansegs;
673 	__le64 sh_ndirtysegs;
674 	__le64 sh_last_alloc;
675 	/* ... */
676 };
677 
678 #define NILFS_SUFILE_FIRST_SEGMENT_USAGE_OFFSET	\
679 	((sizeof(struct nilfs_sufile_header) +				\
680 	  sizeof(struct nilfs_segment_usage) - 1) /			\
681 			 sizeof(struct nilfs_segment_usage))
682 
683 /**
684  * nilfs_suinfo - segment usage information
685  * @sui_lastmod:
686  * @sui_nblocks:
687  * @sui_flags:
688  */
689 struct nilfs_suinfo {
690 	__u64 sui_lastmod;
691 	__u32 sui_nblocks;
692 	__u32 sui_flags;
693 };
694 
695 #define NILFS_SUINFO_FNS(flag, name)					\
696 static inline int							\
697 nilfs_suinfo_##name(const struct nilfs_suinfo *si)			\
698 {									\
699 	return si->sui_flags & (1UL << NILFS_SEGMENT_USAGE_##flag);	\
700 }
701 
NILFS_SUINFO_FNS(ACTIVE,active)702 NILFS_SUINFO_FNS(ACTIVE, active)
703 NILFS_SUINFO_FNS(DIRTY, dirty)
704 NILFS_SUINFO_FNS(ERROR, error)
705 
706 static inline int nilfs_suinfo_clean(const struct nilfs_suinfo *si)
707 {
708 	return !si->sui_flags;
709 }
710 
711 /* ioctl */
712 enum {
713 	NILFS_CHECKPOINT,
714 	NILFS_SNAPSHOT,
715 };
716 
717 /**
718  * struct nilfs_cpmode -
719  * @cc_cno:
720  * @cc_mode:
721  */
722 struct nilfs_cpmode {
723 	__u64 cm_cno;
724 	__u32 cm_mode;
725 	__u32 cm_pad;
726 };
727 
728 /**
729  * struct nilfs_argv - argument vector
730  * @v_base:
731  * @v_nmembs:
732  * @v_size:
733  * @v_flags:
734  * @v_index:
735  */
736 struct nilfs_argv {
737 	__u64 v_base;
738 	__u32 v_nmembs;	/* number of members */
739 	__u16 v_size;	/* size of members */
740 	__u16 v_flags;
741 	__u64 v_index;
742 };
743 
744 /**
745  * struct nilfs_period -
746  * @p_start:
747  * @p_end:
748  */
749 struct nilfs_period {
750 	__u64 p_start;
751 	__u64 p_end;
752 };
753 
754 /**
755  * struct nilfs_cpstat -
756  * @cs_cno: checkpoint number
757  * @cs_ncps: number of checkpoints
758  * @cs_nsss: number of snapshots
759  */
760 struct nilfs_cpstat {
761 	__u64 cs_cno;
762 	__u64 cs_ncps;
763 	__u64 cs_nsss;
764 };
765 
766 /**
767  * struct nilfs_sustat -
768  * @ss_nsegs: number of segments
769  * @ss_ncleansegs: number of clean segments
770  * @ss_ndirtysegs: number of dirty segments
771  * @ss_ctime: creation time of the last segment
772  * @ss_nongc_ctime: creation time of the last segment not for GC
773  * @ss_prot_seq: least sequence number of segments which must not be reclaimed
774  */
775 struct nilfs_sustat {
776 	__u64 ss_nsegs;
777 	__u64 ss_ncleansegs;
778 	__u64 ss_ndirtysegs;
779 	__u64 ss_ctime;
780 	__u64 ss_nongc_ctime;
781 	__u64 ss_prot_seq;
782 };
783 
784 /**
785  * struct nilfs_vinfo - virtual block number information
786  * @vi_vblocknr:
787  * @vi_start:
788  * @vi_end:
789  * @vi_blocknr:
790  */
791 struct nilfs_vinfo {
792 	__u64 vi_vblocknr;
793 	__u64 vi_start;
794 	__u64 vi_end;
795 	__u64 vi_blocknr;
796 };
797 
798 /**
799  * struct nilfs_vdesc -
800  */
801 struct nilfs_vdesc {
802 	__u64 vd_ino;
803 	__u64 vd_cno;
804 	__u64 vd_vblocknr;
805 	struct nilfs_period vd_period;
806 	__u64 vd_blocknr;
807 	__u64 vd_offset;
808 	__u32 vd_flags;
809 	__u32 vd_pad;
810 };
811 
812 /**
813  * struct nilfs_bdesc -
814  */
815 struct nilfs_bdesc {
816 	__u64 bd_ino;
817 	__u64 bd_oblocknr;
818 	__u64 bd_blocknr;
819 	__u64 bd_offset;
820 	__u32 bd_level;
821 	__u32 bd_pad;
822 };
823 
824 #define NILFS_IOCTL_IDENT		'n'
825 
826 #define NILFS_IOCTL_CHANGE_CPMODE  \
827 	_IOW(NILFS_IOCTL_IDENT, 0x80, struct nilfs_cpmode)
828 #define NILFS_IOCTL_DELETE_CHECKPOINT  \
829 	_IOW(NILFS_IOCTL_IDENT, 0x81, __u64)
830 #define NILFS_IOCTL_GET_CPINFO  \
831 	_IOR(NILFS_IOCTL_IDENT, 0x82, struct nilfs_argv)
832 #define NILFS_IOCTL_GET_CPSTAT  \
833 	_IOR(NILFS_IOCTL_IDENT, 0x83, struct nilfs_cpstat)
834 #define NILFS_IOCTL_GET_SUINFO  \
835 	_IOR(NILFS_IOCTL_IDENT, 0x84, struct nilfs_argv)
836 #define NILFS_IOCTL_GET_SUSTAT  \
837 	_IOR(NILFS_IOCTL_IDENT, 0x85, struct nilfs_sustat)
838 #define NILFS_IOCTL_GET_VINFO  \
839 	_IOWR(NILFS_IOCTL_IDENT, 0x86, struct nilfs_argv)
840 #define NILFS_IOCTL_GET_BDESCS  \
841 	_IOWR(NILFS_IOCTL_IDENT, 0x87, struct nilfs_argv)
842 #define NILFS_IOCTL_CLEAN_SEGMENTS  \
843 	_IOW(NILFS_IOCTL_IDENT, 0x88, struct nilfs_argv[5])
844 #define NILFS_IOCTL_SYNC  \
845 	_IOR(NILFS_IOCTL_IDENT, 0x8A, __u64)
846 #define NILFS_IOCTL_RESIZE  \
847 	_IOW(NILFS_IOCTL_IDENT, 0x8B, __u64)
848 
849 #endif	/* _LINUX_NILFS_FS_H */
850