xref: /linux/include/linux/f2fs_fs.h (revision 04eeb606a8383b306f4bc6991da8231b5f3924b0)
1 /**
2  * include/linux/f2fs_fs.h
3  *
4  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5  *             http://www.samsung.com/
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #ifndef _LINUX_F2FS_FS_H
12 #define _LINUX_F2FS_FS_H
13 
14 #include <linux/pagemap.h>
15 #include <linux/types.h>
16 
17 #define F2FS_SUPER_OFFSET		1024	/* byte-size offset */
18 #define F2FS_MIN_LOG_SECTOR_SIZE	9	/* 9 bits for 512 bytes */
19 #define F2FS_MAX_LOG_SECTOR_SIZE	12	/* 12 bits for 4096 bytes */
20 #define F2FS_LOG_SECTORS_PER_BLOCK	3	/* log number for sector/blk */
21 #define F2FS_BLKSIZE			4096	/* support only 4KB block */
22 #define F2FS_MAX_EXTENSION		64	/* # of extension entries */
23 #define F2FS_BLK_ALIGN(x)	(((x) + F2FS_BLKSIZE - 1) / F2FS_BLKSIZE)
24 
25 #define NULL_ADDR		((block_t)0)	/* used as block_t addresses */
26 #define NEW_ADDR		((block_t)-1)	/* used as block_t addresses */
27 
28 /* 0, 1(node nid), 2(meta nid) are reserved node id */
29 #define F2FS_RESERVED_NODE_NUM		3
30 
31 #define F2FS_ROOT_INO(sbi)	(sbi->root_ino_num)
32 #define F2FS_NODE_INO(sbi)	(sbi->node_ino_num)
33 #define F2FS_META_INO(sbi)	(sbi->meta_ino_num)
34 
35 /* This flag is used by node and meta inodes, and by recovery */
36 #define GFP_F2FS_ZERO	(GFP_NOFS | __GFP_ZERO)
37 
38 /*
39  * For further optimization on multi-head logs, on-disk layout supports maximum
40  * 16 logs by default. The number, 16, is expected to cover all the cases
41  * enoughly. The implementaion currently uses no more than 6 logs.
42  * Half the logs are used for nodes, and the other half are used for data.
43  */
44 #define MAX_ACTIVE_LOGS	16
45 #define MAX_ACTIVE_NODE_LOGS	8
46 #define MAX_ACTIVE_DATA_LOGS	8
47 
48 /*
49  * For superblock
50  */
51 struct f2fs_super_block {
52 	__le32 magic;			/* Magic Number */
53 	__le16 major_ver;		/* Major Version */
54 	__le16 minor_ver;		/* Minor Version */
55 	__le32 log_sectorsize;		/* log2 sector size in bytes */
56 	__le32 log_sectors_per_block;	/* log2 # of sectors per block */
57 	__le32 log_blocksize;		/* log2 block size in bytes */
58 	__le32 log_blocks_per_seg;	/* log2 # of blocks per segment */
59 	__le32 segs_per_sec;		/* # of segments per section */
60 	__le32 secs_per_zone;		/* # of sections per zone */
61 	__le32 checksum_offset;		/* checksum offset inside super block */
62 	__le64 block_count;		/* total # of user blocks */
63 	__le32 section_count;		/* total # of sections */
64 	__le32 segment_count;		/* total # of segments */
65 	__le32 segment_count_ckpt;	/* # of segments for checkpoint */
66 	__le32 segment_count_sit;	/* # of segments for SIT */
67 	__le32 segment_count_nat;	/* # of segments for NAT */
68 	__le32 segment_count_ssa;	/* # of segments for SSA */
69 	__le32 segment_count_main;	/* # of segments for main area */
70 	__le32 segment0_blkaddr;	/* start block address of segment 0 */
71 	__le32 cp_blkaddr;		/* start block address of checkpoint */
72 	__le32 sit_blkaddr;		/* start block address of SIT */
73 	__le32 nat_blkaddr;		/* start block address of NAT */
74 	__le32 ssa_blkaddr;		/* start block address of SSA */
75 	__le32 main_blkaddr;		/* start block address of main area */
76 	__le32 root_ino;		/* root inode number */
77 	__le32 node_ino;		/* node inode number */
78 	__le32 meta_ino;		/* meta inode number */
79 	__u8 uuid[16];			/* 128-bit uuid for volume */
80 	__le16 volume_name[512];	/* volume name */
81 	__le32 extension_count;		/* # of extensions below */
82 	__u8 extension_list[F2FS_MAX_EXTENSION][8];	/* extension array */
83 	__le32 cp_payload;
84 } __packed;
85 
86 /*
87  * For checkpoint
88  */
89 #define CP_FSCK_FLAG		0x00000010
90 #define CP_ERROR_FLAG		0x00000008
91 #define CP_COMPACT_SUM_FLAG	0x00000004
92 #define CP_ORPHAN_PRESENT_FLAG	0x00000002
93 #define CP_UMOUNT_FLAG		0x00000001
94 
95 #define F2FS_CP_PACKS		2	/* # of checkpoint packs */
96 
97 struct f2fs_checkpoint {
98 	__le64 checkpoint_ver;		/* checkpoint block version number */
99 	__le64 user_block_count;	/* # of user blocks */
100 	__le64 valid_block_count;	/* # of valid blocks in main area */
101 	__le32 rsvd_segment_count;	/* # of reserved segments for gc */
102 	__le32 overprov_segment_count;	/* # of overprovision segments */
103 	__le32 free_segment_count;	/* # of free segments in main area */
104 
105 	/* information of current node segments */
106 	__le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
107 	__le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
108 	/* information of current data segments */
109 	__le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
110 	__le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
111 	__le32 ckpt_flags;		/* Flags : umount and journal_present */
112 	__le32 cp_pack_total_block_count;	/* total # of one cp pack */
113 	__le32 cp_pack_start_sum;	/* start block number of data summary */
114 	__le32 valid_node_count;	/* Total number of valid nodes */
115 	__le32 valid_inode_count;	/* Total number of valid inodes */
116 	__le32 next_free_nid;		/* Next free node number */
117 	__le32 sit_ver_bitmap_bytesize;	/* Default value 64 */
118 	__le32 nat_ver_bitmap_bytesize; /* Default value 256 */
119 	__le32 checksum_offset;		/* checksum offset inside cp block */
120 	__le64 elapsed_time;		/* mounted time */
121 	/* allocation type of current segment */
122 	unsigned char alloc_type[MAX_ACTIVE_LOGS];
123 
124 	/* SIT and NAT version bitmap */
125 	unsigned char sit_nat_version_bitmap[1];
126 } __packed;
127 
128 /*
129  * For orphan inode management
130  */
131 #define F2FS_ORPHANS_PER_BLOCK	1020
132 
133 #define GET_ORPHAN_BLOCKS(n)	((n + F2FS_ORPHANS_PER_BLOCK - 1) / \
134 					F2FS_ORPHANS_PER_BLOCK)
135 
136 struct f2fs_orphan_block {
137 	__le32 ino[F2FS_ORPHANS_PER_BLOCK];	/* inode numbers */
138 	__le32 reserved;	/* reserved */
139 	__le16 blk_addr;	/* block index in current CP */
140 	__le16 blk_count;	/* Number of orphan inode blocks in CP */
141 	__le32 entry_count;	/* Total number of orphan nodes in current CP */
142 	__le32 check_sum;	/* CRC32 for orphan inode block */
143 } __packed;
144 
145 /*
146  * For NODE structure
147  */
148 struct f2fs_extent {
149 	__le32 fofs;		/* start file offset of the extent */
150 	__le32 blk_addr;	/* start block address of the extent */
151 	__le32 len;		/* lengh of the extent */
152 } __packed;
153 
154 #define F2FS_NAME_LEN		255
155 #define F2FS_INLINE_XATTR_ADDRS	50	/* 200 bytes for inline xattrs */
156 #define DEF_ADDRS_PER_INODE	923	/* Address Pointers in an Inode */
157 #define DEF_NIDS_PER_INODE	5	/* Node IDs in an Inode */
158 #define ADDRS_PER_INODE(fi)	addrs_per_inode(fi)
159 #define ADDRS_PER_BLOCK		1018	/* Address Pointers in a Direct Block */
160 #define NIDS_PER_BLOCK		1018	/* Node IDs in an Indirect Block */
161 
162 #define ADDRS_PER_PAGE(page, fi)	\
163 	(IS_INODE(page) ? ADDRS_PER_INODE(fi) : ADDRS_PER_BLOCK)
164 
165 #define	NODE_DIR1_BLOCK		(DEF_ADDRS_PER_INODE + 1)
166 #define	NODE_DIR2_BLOCK		(DEF_ADDRS_PER_INODE + 2)
167 #define	NODE_IND1_BLOCK		(DEF_ADDRS_PER_INODE + 3)
168 #define	NODE_IND2_BLOCK		(DEF_ADDRS_PER_INODE + 4)
169 #define	NODE_DIND_BLOCK		(DEF_ADDRS_PER_INODE + 5)
170 
171 #define F2FS_INLINE_XATTR	0x01	/* file inline xattr flag */
172 #define F2FS_INLINE_DATA	0x02	/* file inline data flag */
173 
174 #define MAX_INLINE_DATA		(sizeof(__le32) * (DEF_ADDRS_PER_INODE - \
175 						F2FS_INLINE_XATTR_ADDRS - 1))
176 
177 #define INLINE_DATA_OFFSET	(PAGE_CACHE_SIZE - sizeof(struct node_footer) -\
178 				sizeof(__le32) * (DEF_ADDRS_PER_INODE + \
179 				DEF_NIDS_PER_INODE - 1))
180 
181 struct f2fs_inode {
182 	__le16 i_mode;			/* file mode */
183 	__u8 i_advise;			/* file hints */
184 	__u8 i_inline;			/* file inline flags */
185 	__le32 i_uid;			/* user ID */
186 	__le32 i_gid;			/* group ID */
187 	__le32 i_links;			/* links count */
188 	__le64 i_size;			/* file size in bytes */
189 	__le64 i_blocks;		/* file size in blocks */
190 	__le64 i_atime;			/* access time */
191 	__le64 i_ctime;			/* change time */
192 	__le64 i_mtime;			/* modification time */
193 	__le32 i_atime_nsec;		/* access time in nano scale */
194 	__le32 i_ctime_nsec;		/* change time in nano scale */
195 	__le32 i_mtime_nsec;		/* modification time in nano scale */
196 	__le32 i_generation;		/* file version (for NFS) */
197 	__le32 i_current_depth;		/* only for directory depth */
198 	__le32 i_xattr_nid;		/* nid to save xattr */
199 	__le32 i_flags;			/* file attributes */
200 	__le32 i_pino;			/* parent inode number */
201 	__le32 i_namelen;		/* file name length */
202 	__u8 i_name[F2FS_NAME_LEN];	/* file name for SPOR */
203 	__u8 i_dir_level;		/* dentry_level for large dir */
204 
205 	struct f2fs_extent i_ext;	/* caching a largest extent */
206 
207 	__le32 i_addr[DEF_ADDRS_PER_INODE];	/* Pointers to data blocks */
208 
209 	__le32 i_nid[DEF_NIDS_PER_INODE];	/* direct(2), indirect(2),
210 						double_indirect(1) node id */
211 } __packed;
212 
213 struct direct_node {
214 	__le32 addr[ADDRS_PER_BLOCK];	/* array of data block address */
215 } __packed;
216 
217 struct indirect_node {
218 	__le32 nid[NIDS_PER_BLOCK];	/* array of data block address */
219 } __packed;
220 
221 enum {
222 	COLD_BIT_SHIFT = 0,
223 	FSYNC_BIT_SHIFT,
224 	DENT_BIT_SHIFT,
225 	OFFSET_BIT_SHIFT
226 };
227 
228 struct node_footer {
229 	__le32 nid;		/* node id */
230 	__le32 ino;		/* inode nunmber */
231 	__le32 flag;		/* include cold/fsync/dentry marks and offset */
232 	__le64 cp_ver;		/* checkpoint version */
233 	__le32 next_blkaddr;	/* next node page block address */
234 } __packed;
235 
236 struct f2fs_node {
237 	/* can be one of three types: inode, direct, and indirect types */
238 	union {
239 		struct f2fs_inode i;
240 		struct direct_node dn;
241 		struct indirect_node in;
242 	};
243 	struct node_footer footer;
244 } __packed;
245 
246 /*
247  * For NAT entries
248  */
249 #define NAT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_nat_entry))
250 
251 struct f2fs_nat_entry {
252 	__u8 version;		/* latest version of cached nat entry */
253 	__le32 ino;		/* inode number */
254 	__le32 block_addr;	/* block address */
255 } __packed;
256 
257 struct f2fs_nat_block {
258 	struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
259 } __packed;
260 
261 /*
262  * For SIT entries
263  *
264  * Each segment is 2MB in size by default so that a bitmap for validity of
265  * there-in blocks should occupy 64 bytes, 512 bits.
266  * Not allow to change this.
267  */
268 #define SIT_VBLOCK_MAP_SIZE 64
269 #define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry))
270 
271 /*
272  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
273  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
274  * [9:0] : valid block count
275  */
276 #define SIT_VBLOCKS_SHIFT	10
277 #define SIT_VBLOCKS_MASK	((1 << SIT_VBLOCKS_SHIFT) - 1)
278 #define GET_SIT_VBLOCKS(raw_sit)				\
279 	(le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
280 #define GET_SIT_TYPE(raw_sit)					\
281 	((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)	\
282 	 >> SIT_VBLOCKS_SHIFT)
283 
284 struct f2fs_sit_entry {
285 	__le16 vblocks;				/* reference above */
286 	__u8 valid_map[SIT_VBLOCK_MAP_SIZE];	/* bitmap for valid blocks */
287 	__le64 mtime;				/* segment age for cleaning */
288 } __packed;
289 
290 struct f2fs_sit_block {
291 	struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
292 } __packed;
293 
294 /*
295  * For segment summary
296  *
297  * One summary block contains exactly 512 summary entries, which represents
298  * exactly 2MB segment by default. Not allow to change the basic units.
299  *
300  * NOTE: For initializing fields, you must use set_summary
301  *
302  * - If data page, nid represents dnode's nid
303  * - If node page, nid represents the node page's nid.
304  *
305  * The ofs_in_node is used by only data page. It represents offset
306  * from node's page's beginning to get a data block address.
307  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
308  */
309 #define ENTRIES_IN_SUM		512
310 #define	SUMMARY_SIZE		(7)	/* sizeof(struct summary) */
311 #define	SUM_FOOTER_SIZE		(5)	/* sizeof(struct summary_footer) */
312 #define SUM_ENTRY_SIZE		(SUMMARY_SIZE * ENTRIES_IN_SUM)
313 
314 /* a summary entry for a 4KB-sized block in a segment */
315 struct f2fs_summary {
316 	__le32 nid;		/* parent node id */
317 	union {
318 		__u8 reserved[3];
319 		struct {
320 			__u8 version;		/* node version number */
321 			__le16 ofs_in_node;	/* block index in parent node */
322 		} __packed;
323 	};
324 } __packed;
325 
326 /* summary block type, node or data, is stored to the summary_footer */
327 #define SUM_TYPE_NODE		(1)
328 #define SUM_TYPE_DATA		(0)
329 
330 struct summary_footer {
331 	unsigned char entry_type;	/* SUM_TYPE_XXX */
332 	__u32 check_sum;		/* summary checksum */
333 } __packed;
334 
335 #define SUM_JOURNAL_SIZE	(F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
336 				SUM_ENTRY_SIZE)
337 #define NAT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
338 				sizeof(struct nat_journal_entry))
339 #define NAT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
340 				sizeof(struct nat_journal_entry))
341 #define SIT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
342 				sizeof(struct sit_journal_entry))
343 #define SIT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
344 				sizeof(struct sit_journal_entry))
345 /*
346  * frequently updated NAT/SIT entries can be stored in the spare area in
347  * summary blocks
348  */
349 enum {
350 	NAT_JOURNAL = 0,
351 	SIT_JOURNAL
352 };
353 
354 struct nat_journal_entry {
355 	__le32 nid;
356 	struct f2fs_nat_entry ne;
357 } __packed;
358 
359 struct nat_journal {
360 	struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
361 	__u8 reserved[NAT_JOURNAL_RESERVED];
362 } __packed;
363 
364 struct sit_journal_entry {
365 	__le32 segno;
366 	struct f2fs_sit_entry se;
367 } __packed;
368 
369 struct sit_journal {
370 	struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
371 	__u8 reserved[SIT_JOURNAL_RESERVED];
372 } __packed;
373 
374 /* 4KB-sized summary block structure */
375 struct f2fs_summary_block {
376 	struct f2fs_summary entries[ENTRIES_IN_SUM];
377 	union {
378 		__le16 n_nats;
379 		__le16 n_sits;
380 	};
381 	/* spare area is used by NAT or SIT journals */
382 	union {
383 		struct nat_journal nat_j;
384 		struct sit_journal sit_j;
385 	};
386 	struct summary_footer footer;
387 } __packed;
388 
389 /*
390  * For directory operations
391  */
392 #define F2FS_DOT_HASH		0
393 #define F2FS_DDOT_HASH		F2FS_DOT_HASH
394 #define F2FS_MAX_HASH		(~((0x3ULL) << 62))
395 #define F2FS_HASH_COL_BIT	((0x1ULL) << 63)
396 
397 typedef __le32	f2fs_hash_t;
398 
399 /* One directory entry slot covers 8bytes-long file name */
400 #define F2FS_SLOT_LEN		8
401 #define F2FS_SLOT_LEN_BITS	3
402 
403 #define GET_DENTRY_SLOTS(x)	((x + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
404 
405 /* the number of dentry in a block */
406 #define NR_DENTRY_IN_BLOCK	214
407 
408 /* MAX level for dir lookup */
409 #define MAX_DIR_HASH_DEPTH	63
410 
411 /* MAX buckets in one level of dir */
412 #define MAX_DIR_BUCKETS		(1 << ((MAX_DIR_HASH_DEPTH / 2) - 1))
413 
414 #define SIZE_OF_DIR_ENTRY	11	/* by byte */
415 #define SIZE_OF_DENTRY_BITMAP	((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
416 					BITS_PER_BYTE)
417 #define SIZE_OF_RESERVED	(PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
418 				F2FS_SLOT_LEN) * \
419 				NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
420 
421 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
422 struct f2fs_dir_entry {
423 	__le32 hash_code;	/* hash code of file name */
424 	__le32 ino;		/* inode number */
425 	__le16 name_len;	/* lengh of file name */
426 	__u8 file_type;		/* file type */
427 } __packed;
428 
429 /* 4KB-sized directory entry block */
430 struct f2fs_dentry_block {
431 	/* validity bitmap for directory entries in each block */
432 	__u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
433 	__u8 reserved[SIZE_OF_RESERVED];
434 	struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
435 	__u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
436 } __packed;
437 
438 /* file types used in inode_info->flags */
439 enum {
440 	F2FS_FT_UNKNOWN,
441 	F2FS_FT_REG_FILE,
442 	F2FS_FT_DIR,
443 	F2FS_FT_CHRDEV,
444 	F2FS_FT_BLKDEV,
445 	F2FS_FT_FIFO,
446 	F2FS_FT_SOCK,
447 	F2FS_FT_SYMLINK,
448 	F2FS_FT_MAX
449 };
450 
451 #endif  /* _LINUX_F2FS_FS_H */
452