xref: /linux/include/linux/f2fs_fs.h (revision 1e1159bb97cf4191849b4b03f77ab32977c2ece6)
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_LOG_SECTOR_SIZE		9	/* 9 bits for 512 byte */
19 #define F2FS_LOG_SECTORS_PER_BLOCK	3	/* 4KB: F2FS_BLKSIZE */
20 #define F2FS_BLKSIZE			4096	/* support only 4KB block */
21 #define F2FS_MAX_EXTENSION		64	/* # of extension entries */
22 
23 #define NULL_ADDR		((block_t)0)	/* used as block_t addresses */
24 #define NEW_ADDR		((block_t)-1)	/* used as block_t addresses */
25 
26 #define F2FS_ROOT_INO(sbi)	(sbi->root_ino_num)
27 #define F2FS_NODE_INO(sbi)	(sbi->node_ino_num)
28 #define F2FS_META_INO(sbi)	(sbi->meta_ino_num)
29 
30 /* This flag is used by node and meta inodes, and by recovery */
31 #define GFP_F2FS_ZERO	(GFP_NOFS | __GFP_ZERO)
32 
33 /*
34  * For further optimization on multi-head logs, on-disk layout supports maximum
35  * 16 logs by default. The number, 16, is expected to cover all the cases
36  * enoughly. The implementaion currently uses no more than 6 logs.
37  * Half the logs are used for nodes, and the other half are used for data.
38  */
39 #define MAX_ACTIVE_LOGS	16
40 #define MAX_ACTIVE_NODE_LOGS	8
41 #define MAX_ACTIVE_DATA_LOGS	8
42 
43 /*
44  * For superblock
45  */
46 struct f2fs_super_block {
47 	__le32 magic;			/* Magic Number */
48 	__le16 major_ver;		/* Major Version */
49 	__le16 minor_ver;		/* Minor Version */
50 	__le32 log_sectorsize;		/* log2 sector size in bytes */
51 	__le32 log_sectors_per_block;	/* log2 # of sectors per block */
52 	__le32 log_blocksize;		/* log2 block size in bytes */
53 	__le32 log_blocks_per_seg;	/* log2 # of blocks per segment */
54 	__le32 segs_per_sec;		/* # of segments per section */
55 	__le32 secs_per_zone;		/* # of sections per zone */
56 	__le32 checksum_offset;		/* checksum offset inside super block */
57 	__le64 block_count;		/* total # of user blocks */
58 	__le32 section_count;		/* total # of sections */
59 	__le32 segment_count;		/* total # of segments */
60 	__le32 segment_count_ckpt;	/* # of segments for checkpoint */
61 	__le32 segment_count_sit;	/* # of segments for SIT */
62 	__le32 segment_count_nat;	/* # of segments for NAT */
63 	__le32 segment_count_ssa;	/* # of segments for SSA */
64 	__le32 segment_count_main;	/* # of segments for main area */
65 	__le32 segment0_blkaddr;	/* start block address of segment 0 */
66 	__le32 cp_blkaddr;		/* start block address of checkpoint */
67 	__le32 sit_blkaddr;		/* start block address of SIT */
68 	__le32 nat_blkaddr;		/* start block address of NAT */
69 	__le32 ssa_blkaddr;		/* start block address of SSA */
70 	__le32 main_blkaddr;		/* start block address of main area */
71 	__le32 root_ino;		/* root inode number */
72 	__le32 node_ino;		/* node inode number */
73 	__le32 meta_ino;		/* meta inode number */
74 	__u8 uuid[16];			/* 128-bit uuid for volume */
75 	__le16 volume_name[512];	/* volume name */
76 	__le32 extension_count;		/* # of extensions below */
77 	__u8 extension_list[F2FS_MAX_EXTENSION][8];	/* extension array */
78 } __packed;
79 
80 /*
81  * For checkpoint
82  */
83 #define CP_ERROR_FLAG		0x00000008
84 #define CP_COMPACT_SUM_FLAG	0x00000004
85 #define CP_ORPHAN_PRESENT_FLAG	0x00000002
86 #define CP_UMOUNT_FLAG		0x00000001
87 
88 struct f2fs_checkpoint {
89 	__le64 checkpoint_ver;		/* checkpoint block version number */
90 	__le64 user_block_count;	/* # of user blocks */
91 	__le64 valid_block_count;	/* # of valid blocks in main area */
92 	__le32 rsvd_segment_count;	/* # of reserved segments for gc */
93 	__le32 overprov_segment_count;	/* # of overprovision segments */
94 	__le32 free_segment_count;	/* # of free segments in main area */
95 
96 	/* information of current node segments */
97 	__le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
98 	__le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
99 	/* information of current data segments */
100 	__le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
101 	__le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
102 	__le32 ckpt_flags;		/* Flags : umount and journal_present */
103 	__le32 cp_pack_total_block_count;	/* total # of one cp pack */
104 	__le32 cp_pack_start_sum;	/* start block number of data summary */
105 	__le32 valid_node_count;	/* Total number of valid nodes */
106 	__le32 valid_inode_count;	/* Total number of valid inodes */
107 	__le32 next_free_nid;		/* Next free node number */
108 	__le32 sit_ver_bitmap_bytesize;	/* Default value 64 */
109 	__le32 nat_ver_bitmap_bytesize; /* Default value 256 */
110 	__le32 checksum_offset;		/* checksum offset inside cp block */
111 	__le64 elapsed_time;		/* mounted time */
112 	/* allocation type of current segment */
113 	unsigned char alloc_type[MAX_ACTIVE_LOGS];
114 
115 	/* SIT and NAT version bitmap */
116 	unsigned char sit_nat_version_bitmap[1];
117 } __packed;
118 
119 /*
120  * For orphan inode management
121  */
122 #define F2FS_ORPHANS_PER_BLOCK	1020
123 
124 struct f2fs_orphan_block {
125 	__le32 ino[F2FS_ORPHANS_PER_BLOCK];	/* inode numbers */
126 	__le32 reserved;	/* reserved */
127 	__le16 blk_addr;	/* block index in current CP */
128 	__le16 blk_count;	/* Number of orphan inode blocks in CP */
129 	__le32 entry_count;	/* Total number of orphan nodes in current CP */
130 	__le32 check_sum;	/* CRC32 for orphan inode block */
131 } __packed;
132 
133 /*
134  * For NODE structure
135  */
136 struct f2fs_extent {
137 	__le32 fofs;		/* start file offset of the extent */
138 	__le32 blk_addr;	/* start block address of the extent */
139 	__le32 len;		/* lengh of the extent */
140 } __packed;
141 
142 #define F2FS_NAME_LEN		255
143 #define F2FS_INLINE_XATTR_ADDRS	50	/* 200 bytes for inline xattrs */
144 #define DEF_ADDRS_PER_INODE	923	/* Address Pointers in an Inode */
145 #define ADDRS_PER_INODE(fi)	addrs_per_inode(fi)
146 #define ADDRS_PER_BLOCK		1018	/* Address Pointers in a Direct Block */
147 #define NIDS_PER_BLOCK		1018	/* Node IDs in an Indirect Block */
148 
149 #define	NODE_DIR1_BLOCK		(DEF_ADDRS_PER_INODE + 1)
150 #define	NODE_DIR2_BLOCK		(DEF_ADDRS_PER_INODE + 2)
151 #define	NODE_IND1_BLOCK		(DEF_ADDRS_PER_INODE + 3)
152 #define	NODE_IND2_BLOCK		(DEF_ADDRS_PER_INODE + 4)
153 #define	NODE_DIND_BLOCK		(DEF_ADDRS_PER_INODE + 5)
154 
155 #define F2FS_INLINE_XATTR	0x01	/* file inline xattr flag */
156 
157 struct f2fs_inode {
158 	__le16 i_mode;			/* file mode */
159 	__u8 i_advise;			/* file hints */
160 	__u8 i_inline;			/* file inline flags */
161 	__le32 i_uid;			/* user ID */
162 	__le32 i_gid;			/* group ID */
163 	__le32 i_links;			/* links count */
164 	__le64 i_size;			/* file size in bytes */
165 	__le64 i_blocks;		/* file size in blocks */
166 	__le64 i_atime;			/* access time */
167 	__le64 i_ctime;			/* change time */
168 	__le64 i_mtime;			/* modification time */
169 	__le32 i_atime_nsec;		/* access time in nano scale */
170 	__le32 i_ctime_nsec;		/* change time in nano scale */
171 	__le32 i_mtime_nsec;		/* modification time in nano scale */
172 	__le32 i_generation;		/* file version (for NFS) */
173 	__le32 i_current_depth;		/* only for directory depth */
174 	__le32 i_xattr_nid;		/* nid to save xattr */
175 	__le32 i_flags;			/* file attributes */
176 	__le32 i_pino;			/* parent inode number */
177 	__le32 i_namelen;		/* file name length */
178 	__u8 i_name[F2FS_NAME_LEN];	/* file name for SPOR */
179 	__u8 i_reserved2;		/* for backward compatibility */
180 
181 	struct f2fs_extent i_ext;	/* caching a largest extent */
182 
183 	__le32 i_addr[DEF_ADDRS_PER_INODE];	/* Pointers to data blocks */
184 
185 	__le32 i_nid[5];		/* direct(2), indirect(2),
186 						double_indirect(1) node id */
187 } __packed;
188 
189 struct direct_node {
190 	__le32 addr[ADDRS_PER_BLOCK];	/* array of data block address */
191 } __packed;
192 
193 struct indirect_node {
194 	__le32 nid[NIDS_PER_BLOCK];	/* array of data block address */
195 } __packed;
196 
197 enum {
198 	COLD_BIT_SHIFT = 0,
199 	FSYNC_BIT_SHIFT,
200 	DENT_BIT_SHIFT,
201 	OFFSET_BIT_SHIFT
202 };
203 
204 struct node_footer {
205 	__le32 nid;		/* node id */
206 	__le32 ino;		/* inode nunmber */
207 	__le32 flag;		/* include cold/fsync/dentry marks and offset */
208 	__le64 cp_ver;		/* checkpoint version */
209 	__le32 next_blkaddr;	/* next node page block address */
210 } __packed;
211 
212 struct f2fs_node {
213 	/* can be one of three types: inode, direct, and indirect types */
214 	union {
215 		struct f2fs_inode i;
216 		struct direct_node dn;
217 		struct indirect_node in;
218 	};
219 	struct node_footer footer;
220 } __packed;
221 
222 /*
223  * For NAT entries
224  */
225 #define NAT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_nat_entry))
226 
227 struct f2fs_nat_entry {
228 	__u8 version;		/* latest version of cached nat entry */
229 	__le32 ino;		/* inode number */
230 	__le32 block_addr;	/* block address */
231 } __packed;
232 
233 struct f2fs_nat_block {
234 	struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
235 } __packed;
236 
237 /*
238  * For SIT entries
239  *
240  * Each segment is 2MB in size by default so that a bitmap for validity of
241  * there-in blocks should occupy 64 bytes, 512 bits.
242  * Not allow to change this.
243  */
244 #define SIT_VBLOCK_MAP_SIZE 64
245 #define SIT_ENTRY_PER_BLOCK (PAGE_CACHE_SIZE / sizeof(struct f2fs_sit_entry))
246 
247 /*
248  * Note that f2fs_sit_entry->vblocks has the following bit-field information.
249  * [15:10] : allocation type such as CURSEG_XXXX_TYPE
250  * [9:0] : valid block count
251  */
252 #define SIT_VBLOCKS_SHIFT	10
253 #define SIT_VBLOCKS_MASK	((1 << SIT_VBLOCKS_SHIFT) - 1)
254 #define GET_SIT_VBLOCKS(raw_sit)				\
255 	(le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
256 #define GET_SIT_TYPE(raw_sit)					\
257 	((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)	\
258 	 >> SIT_VBLOCKS_SHIFT)
259 
260 struct f2fs_sit_entry {
261 	__le16 vblocks;				/* reference above */
262 	__u8 valid_map[SIT_VBLOCK_MAP_SIZE];	/* bitmap for valid blocks */
263 	__le64 mtime;				/* segment age for cleaning */
264 } __packed;
265 
266 struct f2fs_sit_block {
267 	struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
268 } __packed;
269 
270 /*
271  * For segment summary
272  *
273  * One summary block contains exactly 512 summary entries, which represents
274  * exactly 2MB segment by default. Not allow to change the basic units.
275  *
276  * NOTE: For initializing fields, you must use set_summary
277  *
278  * - If data page, nid represents dnode's nid
279  * - If node page, nid represents the node page's nid.
280  *
281  * The ofs_in_node is used by only data page. It represents offset
282  * from node's page's beginning to get a data block address.
283  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
284  */
285 #define ENTRIES_IN_SUM		512
286 #define	SUMMARY_SIZE		(7)	/* sizeof(struct summary) */
287 #define	SUM_FOOTER_SIZE		(5)	/* sizeof(struct summary_footer) */
288 #define SUM_ENTRY_SIZE		(SUMMARY_SIZE * ENTRIES_IN_SUM)
289 
290 /* a summary entry for a 4KB-sized block in a segment */
291 struct f2fs_summary {
292 	__le32 nid;		/* parent node id */
293 	union {
294 		__u8 reserved[3];
295 		struct {
296 			__u8 version;		/* node version number */
297 			__le16 ofs_in_node;	/* block index in parent node */
298 		} __packed;
299 	};
300 } __packed;
301 
302 /* summary block type, node or data, is stored to the summary_footer */
303 #define SUM_TYPE_NODE		(1)
304 #define SUM_TYPE_DATA		(0)
305 
306 struct summary_footer {
307 	unsigned char entry_type;	/* SUM_TYPE_XXX */
308 	__u32 check_sum;		/* summary checksum */
309 } __packed;
310 
311 #define SUM_JOURNAL_SIZE	(F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
312 				SUM_ENTRY_SIZE)
313 #define NAT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
314 				sizeof(struct nat_journal_entry))
315 #define NAT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
316 				sizeof(struct nat_journal_entry))
317 #define SIT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
318 				sizeof(struct sit_journal_entry))
319 #define SIT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
320 				sizeof(struct sit_journal_entry))
321 /*
322  * frequently updated NAT/SIT entries can be stored in the spare area in
323  * summary blocks
324  */
325 enum {
326 	NAT_JOURNAL = 0,
327 	SIT_JOURNAL
328 };
329 
330 struct nat_journal_entry {
331 	__le32 nid;
332 	struct f2fs_nat_entry ne;
333 } __packed;
334 
335 struct nat_journal {
336 	struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
337 	__u8 reserved[NAT_JOURNAL_RESERVED];
338 } __packed;
339 
340 struct sit_journal_entry {
341 	__le32 segno;
342 	struct f2fs_sit_entry se;
343 } __packed;
344 
345 struct sit_journal {
346 	struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
347 	__u8 reserved[SIT_JOURNAL_RESERVED];
348 } __packed;
349 
350 /* 4KB-sized summary block structure */
351 struct f2fs_summary_block {
352 	struct f2fs_summary entries[ENTRIES_IN_SUM];
353 	union {
354 		__le16 n_nats;
355 		__le16 n_sits;
356 	};
357 	/* spare area is used by NAT or SIT journals */
358 	union {
359 		struct nat_journal nat_j;
360 		struct sit_journal sit_j;
361 	};
362 	struct summary_footer footer;
363 } __packed;
364 
365 /*
366  * For directory operations
367  */
368 #define F2FS_DOT_HASH		0
369 #define F2FS_DDOT_HASH		F2FS_DOT_HASH
370 #define F2FS_MAX_HASH		(~((0x3ULL) << 62))
371 #define F2FS_HASH_COL_BIT	((0x1ULL) << 63)
372 
373 typedef __le32	f2fs_hash_t;
374 
375 /* One directory entry slot covers 8bytes-long file name */
376 #define F2FS_SLOT_LEN		8
377 #define F2FS_SLOT_LEN_BITS	3
378 
379 #define GET_DENTRY_SLOTS(x)	((x + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
380 
381 /* the number of dentry in a block */
382 #define NR_DENTRY_IN_BLOCK	214
383 
384 /* MAX level for dir lookup */
385 #define MAX_DIR_HASH_DEPTH	63
386 
387 #define SIZE_OF_DIR_ENTRY	11	/* by byte */
388 #define SIZE_OF_DENTRY_BITMAP	((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
389 					BITS_PER_BYTE)
390 #define SIZE_OF_RESERVED	(PAGE_SIZE - ((SIZE_OF_DIR_ENTRY + \
391 				F2FS_SLOT_LEN) * \
392 				NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
393 
394 /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
395 struct f2fs_dir_entry {
396 	__le32 hash_code;	/* hash code of file name */
397 	__le32 ino;		/* inode number */
398 	__le16 name_len;	/* lengh of file name */
399 	__u8 file_type;		/* file type */
400 } __packed;
401 
402 /* 4KB-sized directory entry block */
403 struct f2fs_dentry_block {
404 	/* validity bitmap for directory entries in each block */
405 	__u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
406 	__u8 reserved[SIZE_OF_RESERVED];
407 	struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
408 	__u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
409 } __packed;
410 
411 /* file types used in inode_info->flags */
412 enum {
413 	F2FS_FT_UNKNOWN,
414 	F2FS_FT_REG_FILE,
415 	F2FS_FT_DIR,
416 	F2FS_FT_CHRDEV,
417 	F2FS_FT_BLKDEV,
418 	F2FS_FT_FIFO,
419 	F2FS_FT_SOCK,
420 	F2FS_FT_SYMLINK,
421 	F2FS_FT_MAX
422 };
423 
424 #endif  /* _LINUX_F2FS_FS_H */
425