1  // SPDX-License-Identifier: GPL-2.0
2  /**
3   * include/linux/f2fs_fs.h
4   *
5   * Copyright (c) 2012 Samsung Electronics Co., Ltd.
6   *             http://www.samsung.com/
7   */
8  #ifndef _LINUX_F2FS_FS_H
9  #define _LINUX_F2FS_FS_H
10  
11  #include <linux/pagemap.h>
12  #include <linux/types.h>
13  
14  #define F2FS_SUPER_OFFSET		1024	/* byte-size offset */
15  #define F2FS_MIN_LOG_SECTOR_SIZE	9	/* 9 bits for 512 bytes */
16  #define F2FS_MAX_LOG_SECTOR_SIZE	PAGE_SHIFT	/* Max is Block Size */
17  #define F2FS_LOG_SECTORS_PER_BLOCK	(PAGE_SHIFT - 9) /* log number for sector/blk */
18  #define F2FS_BLKSIZE			PAGE_SIZE /* support only block == page */
19  #define F2FS_BLKSIZE_BITS		PAGE_SHIFT /* bits for F2FS_BLKSIZE */
20  #define F2FS_MAX_EXTENSION		64	/* # of extension entries */
21  #define F2FS_EXTENSION_LEN		8	/* max size of extension */
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  #define COMPRESS_ADDR		((block_t)-2)	/* used as compressed data flag */
26  
27  #define F2FS_BYTES_TO_BLK(bytes)	((bytes) >> F2FS_BLKSIZE_BITS)
28  #define F2FS_BLK_TO_BYTES(blk)		((blk) << F2FS_BLKSIZE_BITS)
29  #define F2FS_BLK_END_BYTES(blk)		(F2FS_BLK_TO_BYTES(blk + 1) - 1)
30  #define F2FS_BLK_ALIGN(x)			(F2FS_BYTES_TO_BLK((x) + F2FS_BLKSIZE - 1))
31  
32  /* 0, 1(node nid), 2(meta nid) are reserved node id */
33  #define F2FS_RESERVED_NODE_NUM		3
34  
35  #define F2FS_ROOT_INO(sbi)	((sbi)->root_ino_num)
36  #define F2FS_NODE_INO(sbi)	((sbi)->node_ino_num)
37  #define F2FS_META_INO(sbi)	((sbi)->meta_ino_num)
38  #define F2FS_COMPRESS_INO(sbi)	(NM_I(sbi)->max_nid)
39  
40  #define F2FS_MAX_QUOTAS		3
41  
42  #define F2FS_ENC_UTF8_12_1	1
43  
44  /* This flag is used by node and meta inodes, and by recovery */
45  #define GFP_F2FS_ZERO		(GFP_NOFS | __GFP_ZERO)
46  
47  /*
48   * For further optimization on multi-head logs, on-disk layout supports maximum
49   * 16 logs by default. The number, 16, is expected to cover all the cases
50   * enoughly. The implementaion currently uses no more than 6 logs.
51   * Half the logs are used for nodes, and the other half are used for data.
52   */
53  #define MAX_ACTIVE_LOGS	16
54  #define MAX_ACTIVE_NODE_LOGS	8
55  #define MAX_ACTIVE_DATA_LOGS	8
56  
57  #define VERSION_LEN	256
58  #define MAX_VOLUME_NAME		512
59  #define MAX_PATH_LEN		64
60  #define MAX_DEVICES		8
61  
62  /*
63   * For superblock
64   */
65  struct f2fs_device {
66  	__u8 path[MAX_PATH_LEN];
67  	__le32 total_segments;
68  } __packed;
69  
70  /* reason of stop_checkpoint */
71  enum stop_cp_reason {
72  	STOP_CP_REASON_SHUTDOWN,
73  	STOP_CP_REASON_FAULT_INJECT,
74  	STOP_CP_REASON_META_PAGE,
75  	STOP_CP_REASON_WRITE_FAIL,
76  	STOP_CP_REASON_CORRUPTED_SUMMARY,
77  	STOP_CP_REASON_UPDATE_INODE,
78  	STOP_CP_REASON_FLUSH_FAIL,
79  	STOP_CP_REASON_NO_SEGMENT,
80  	STOP_CP_REASON_MAX,
81  };
82  
83  #define	MAX_STOP_REASON			32
84  
85  /* detail reason for EFSCORRUPTED */
86  enum f2fs_error {
87  	ERROR_CORRUPTED_CLUSTER,
88  	ERROR_FAIL_DECOMPRESSION,
89  	ERROR_INVALID_BLKADDR,
90  	ERROR_CORRUPTED_DIRENT,
91  	ERROR_CORRUPTED_INODE,
92  	ERROR_INCONSISTENT_SUMMARY,
93  	ERROR_INCONSISTENT_FOOTER,
94  	ERROR_INCONSISTENT_SUM_TYPE,
95  	ERROR_CORRUPTED_JOURNAL,
96  	ERROR_INCONSISTENT_NODE_COUNT,
97  	ERROR_INCONSISTENT_BLOCK_COUNT,
98  	ERROR_INVALID_CURSEG,
99  	ERROR_INCONSISTENT_SIT,
100  	ERROR_CORRUPTED_VERITY_XATTR,
101  	ERROR_CORRUPTED_XATTR,
102  	ERROR_INVALID_NODE_REFERENCE,
103  	ERROR_INCONSISTENT_NAT,
104  	ERROR_MAX,
105  };
106  
107  #define MAX_F2FS_ERRORS			16
108  
109  struct f2fs_super_block {
110  	__le32 magic;			/* Magic Number */
111  	__le16 major_ver;		/* Major Version */
112  	__le16 minor_ver;		/* Minor Version */
113  	__le32 log_sectorsize;		/* log2 sector size in bytes */
114  	__le32 log_sectors_per_block;	/* log2 # of sectors per block */
115  	__le32 log_blocksize;		/* log2 block size in bytes */
116  	__le32 log_blocks_per_seg;	/* log2 # of blocks per segment */
117  	__le32 segs_per_sec;		/* # of segments per section */
118  	__le32 secs_per_zone;		/* # of sections per zone */
119  	__le32 checksum_offset;		/* checksum offset inside super block */
120  	__le64 block_count;		/* total # of user blocks */
121  	__le32 section_count;		/* total # of sections */
122  	__le32 segment_count;		/* total # of segments */
123  	__le32 segment_count_ckpt;	/* # of segments for checkpoint */
124  	__le32 segment_count_sit;	/* # of segments for SIT */
125  	__le32 segment_count_nat;	/* # of segments for NAT */
126  	__le32 segment_count_ssa;	/* # of segments for SSA */
127  	__le32 segment_count_main;	/* # of segments for main area */
128  	__le32 segment0_blkaddr;	/* start block address of segment 0 */
129  	__le32 cp_blkaddr;		/* start block address of checkpoint */
130  	__le32 sit_blkaddr;		/* start block address of SIT */
131  	__le32 nat_blkaddr;		/* start block address of NAT */
132  	__le32 ssa_blkaddr;		/* start block address of SSA */
133  	__le32 main_blkaddr;		/* start block address of main area */
134  	__le32 root_ino;		/* root inode number */
135  	__le32 node_ino;		/* node inode number */
136  	__le32 meta_ino;		/* meta inode number */
137  	__u8 uuid[16];			/* 128-bit uuid for volume */
138  	__le16 volume_name[MAX_VOLUME_NAME];	/* volume name */
139  	__le32 extension_count;		/* # of extensions below */
140  	__u8 extension_list[F2FS_MAX_EXTENSION][F2FS_EXTENSION_LEN];/* extension array */
141  	__le32 cp_payload;
142  	__u8 version[VERSION_LEN];	/* the kernel version */
143  	__u8 init_version[VERSION_LEN];	/* the initial kernel version */
144  	__le32 feature;			/* defined features */
145  	__u8 encryption_level;		/* versioning level for encryption */
146  	__u8 encrypt_pw_salt[16];	/* Salt used for string2key algorithm */
147  	struct f2fs_device devs[MAX_DEVICES];	/* device list */
148  	__le32 qf_ino[F2FS_MAX_QUOTAS];	/* quota inode numbers */
149  	__u8 hot_ext_count;		/* # of hot file extension */
150  	__le16  s_encoding;		/* Filename charset encoding */
151  	__le16  s_encoding_flags;	/* Filename charset encoding flags */
152  	__u8 s_stop_reason[MAX_STOP_REASON];	/* stop checkpoint reason */
153  	__u8 s_errors[MAX_F2FS_ERRORS];		/* reason of image corrupts */
154  	__u8 reserved[258];		/* valid reserved region */
155  	__le32 crc;			/* checksum of superblock */
156  } __packed;
157  
158  /*
159   * For checkpoint
160   */
161  #define CP_RESIZEFS_FLAG		0x00004000
162  #define CP_DISABLED_QUICK_FLAG		0x00002000
163  #define CP_DISABLED_FLAG		0x00001000
164  #define CP_QUOTA_NEED_FSCK_FLAG		0x00000800
165  #define CP_LARGE_NAT_BITMAP_FLAG	0x00000400
166  #define CP_NOCRC_RECOVERY_FLAG	0x00000200
167  #define CP_TRIMMED_FLAG		0x00000100
168  #define CP_NAT_BITS_FLAG	0x00000080
169  #define CP_CRC_RECOVERY_FLAG	0x00000040
170  #define CP_FASTBOOT_FLAG	0x00000020
171  #define CP_FSCK_FLAG		0x00000010
172  #define CP_ERROR_FLAG		0x00000008
173  #define CP_COMPACT_SUM_FLAG	0x00000004
174  #define CP_ORPHAN_PRESENT_FLAG	0x00000002
175  #define CP_UMOUNT_FLAG		0x00000001
176  
177  #define F2FS_CP_PACKS		2	/* # of checkpoint packs */
178  
179  struct f2fs_checkpoint {
180  	__le64 checkpoint_ver;		/* checkpoint block version number */
181  	__le64 user_block_count;	/* # of user blocks */
182  	__le64 valid_block_count;	/* # of valid blocks in main area */
183  	__le32 rsvd_segment_count;	/* # of reserved segments for gc */
184  	__le32 overprov_segment_count;	/* # of overprovision segments */
185  	__le32 free_segment_count;	/* # of free segments in main area */
186  
187  	/* information of current node segments */
188  	__le32 cur_node_segno[MAX_ACTIVE_NODE_LOGS];
189  	__le16 cur_node_blkoff[MAX_ACTIVE_NODE_LOGS];
190  	/* information of current data segments */
191  	__le32 cur_data_segno[MAX_ACTIVE_DATA_LOGS];
192  	__le16 cur_data_blkoff[MAX_ACTIVE_DATA_LOGS];
193  	__le32 ckpt_flags;		/* Flags : umount and journal_present */
194  	__le32 cp_pack_total_block_count;	/* total # of one cp pack */
195  	__le32 cp_pack_start_sum;	/* start block number of data summary */
196  	__le32 valid_node_count;	/* Total number of valid nodes */
197  	__le32 valid_inode_count;	/* Total number of valid inodes */
198  	__le32 next_free_nid;		/* Next free node number */
199  	__le32 sit_ver_bitmap_bytesize;	/* Default value 64 */
200  	__le32 nat_ver_bitmap_bytesize; /* Default value 256 */
201  	__le32 checksum_offset;		/* checksum offset inside cp block */
202  	__le64 elapsed_time;		/* mounted time */
203  	/* allocation type of current segment */
204  	unsigned char alloc_type[MAX_ACTIVE_LOGS];
205  
206  	/* SIT and NAT version bitmap */
207  	unsigned char sit_nat_version_bitmap[];
208  } __packed;
209  
210  #define CP_CHKSUM_OFFSET	(F2FS_BLKSIZE - sizeof(__le32))	/* default chksum offset in checkpoint */
211  #define CP_MIN_CHKSUM_OFFSET						\
212  	(offsetof(struct f2fs_checkpoint, sit_nat_version_bitmap))
213  
214  /*
215   * For orphan inode management
216   */
217  #define F2FS_ORPHANS_PER_BLOCK	((F2FS_BLKSIZE - 4 * sizeof(__le32)) / sizeof(__le32))
218  
219  #define GET_ORPHAN_BLOCKS(n)	(((n) + F2FS_ORPHANS_PER_BLOCK - 1) / \
220  					F2FS_ORPHANS_PER_BLOCK)
221  
222  struct f2fs_orphan_block {
223  	__le32 ino[F2FS_ORPHANS_PER_BLOCK];	/* inode numbers */
224  	__le32 reserved;	/* reserved */
225  	__le16 blk_addr;	/* block index in current CP */
226  	__le16 blk_count;	/* Number of orphan inode blocks in CP */
227  	__le32 entry_count;	/* Total number of orphan nodes in current CP */
228  	__le32 check_sum;	/* CRC32 for orphan inode block */
229  } __packed;
230  
231  /*
232   * For NODE structure
233   */
234  struct f2fs_extent {
235  	__le32 fofs;		/* start file offset of the extent */
236  	__le32 blk;		/* start block address of the extent */
237  	__le32 len;		/* length of the extent */
238  } __packed;
239  
240  #define F2FS_NAME_LEN		255
241  /* 200 bytes for inline xattrs by default */
242  #define DEFAULT_INLINE_XATTR_ADDRS	50
243  
244  #define OFFSET_OF_END_OF_I_EXT		360
245  #define SIZE_OF_I_NID			20
246  
247  struct node_footer {
248  	__le32 nid;		/* node id */
249  	__le32 ino;		/* inode number */
250  	__le32 flag;		/* include cold/fsync/dentry marks and offset */
251  	__le64 cp_ver;		/* checkpoint version */
252  	__le32 next_blkaddr;	/* next node page block address */
253  } __packed;
254  
255  /* Address Pointers in an Inode */
256  #define DEF_ADDRS_PER_INODE	((F2FS_BLKSIZE - OFFSET_OF_END_OF_I_EXT	\
257  					- SIZE_OF_I_NID	\
258  					- sizeof(struct node_footer)) / sizeof(__le32))
259  #define CUR_ADDRS_PER_INODE(inode)	(DEF_ADDRS_PER_INODE - \
260  					get_extra_isize(inode))
261  #define DEF_NIDS_PER_INODE	5	/* Node IDs in an Inode */
262  #define ADDRS_PER_INODE(inode)	addrs_per_page(inode, true)
263  /* Address Pointers in a Direct Block */
264  #define DEF_ADDRS_PER_BLOCK	((F2FS_BLKSIZE - sizeof(struct node_footer)) / sizeof(__le32))
265  #define ADDRS_PER_BLOCK(inode)	addrs_per_page(inode, false)
266  /* Node IDs in an Indirect Block */
267  #define NIDS_PER_BLOCK		((F2FS_BLKSIZE - sizeof(struct node_footer)) / sizeof(__le32))
268  
269  #define ADDRS_PER_PAGE(page, inode)	(addrs_per_page(inode, IS_INODE(page)))
270  
271  #define	NODE_DIR1_BLOCK		(DEF_ADDRS_PER_INODE + 1)
272  #define	NODE_DIR2_BLOCK		(DEF_ADDRS_PER_INODE + 2)
273  #define	NODE_IND1_BLOCK		(DEF_ADDRS_PER_INODE + 3)
274  #define	NODE_IND2_BLOCK		(DEF_ADDRS_PER_INODE + 4)
275  #define	NODE_DIND_BLOCK		(DEF_ADDRS_PER_INODE + 5)
276  
277  #define F2FS_INLINE_XATTR	0x01	/* file inline xattr flag */
278  #define F2FS_INLINE_DATA	0x02	/* file inline data flag */
279  #define F2FS_INLINE_DENTRY	0x04	/* file inline dentry flag */
280  #define F2FS_DATA_EXIST		0x08	/* file inline data exist flag */
281  #define F2FS_INLINE_DOTS	0x10	/* file having implicit dot dentries (obsolete) */
282  #define F2FS_EXTRA_ATTR		0x20	/* file having extra attribute */
283  #define F2FS_PIN_FILE		0x40	/* file should not be gced */
284  #define F2FS_COMPRESS_RELEASED	0x80	/* file released compressed blocks */
285  
286  struct f2fs_inode {
287  	__le16 i_mode;			/* file mode */
288  	__u8 i_advise;			/* file hints */
289  	__u8 i_inline;			/* file inline flags */
290  	__le32 i_uid;			/* user ID */
291  	__le32 i_gid;			/* group ID */
292  	__le32 i_links;			/* links count */
293  	__le64 i_size;			/* file size in bytes */
294  	__le64 i_blocks;		/* file size in blocks */
295  	__le64 i_atime;			/* access time */
296  	__le64 i_ctime;			/* change time */
297  	__le64 i_mtime;			/* modification time */
298  	__le32 i_atime_nsec;		/* access time in nano scale */
299  	__le32 i_ctime_nsec;		/* change time in nano scale */
300  	__le32 i_mtime_nsec;		/* modification time in nano scale */
301  	__le32 i_generation;		/* file version (for NFS) */
302  	union {
303  		__le32 i_current_depth;	/* only for directory depth */
304  		__le16 i_gc_failures;	/*
305  					 * # of gc failures on pinned file.
306  					 * only for regular files.
307  					 */
308  	};
309  	__le32 i_xattr_nid;		/* nid to save xattr */
310  	__le32 i_flags;			/* file attributes */
311  	__le32 i_pino;			/* parent inode number */
312  	__le32 i_namelen;		/* file name length */
313  	__u8 i_name[F2FS_NAME_LEN];	/* file name for SPOR */
314  	__u8 i_dir_level;		/* dentry_level for large dir */
315  
316  	struct f2fs_extent i_ext;	/* caching a largest extent */
317  
318  	union {
319  		struct {
320  			__le16 i_extra_isize;	/* extra inode attribute size */
321  			__le16 i_inline_xattr_size;	/* inline xattr size, unit: 4 bytes */
322  			__le32 i_projid;	/* project id */
323  			__le32 i_inode_checksum;/* inode meta checksum */
324  			__le64 i_crtime;	/* creation time */
325  			__le32 i_crtime_nsec;	/* creation time in nano scale */
326  			__le64 i_compr_blocks;	/* # of compressed blocks */
327  			__u8 i_compress_algorithm;	/* compress algorithm */
328  			__u8 i_log_cluster_size;	/* log of cluster size */
329  			__le16 i_compress_flag;		/* compress flag */
330  						/* 0 bit: chksum flag
331  						 * [8,15] bits: compress level
332  						 */
333  			__le32 i_extra_end[0];	/* for attribute size calculation */
334  		} __packed;
335  		__le32 i_addr[DEF_ADDRS_PER_INODE];	/* Pointers to data blocks */
336  	};
337  	__le32 i_nid[DEF_NIDS_PER_INODE];	/* direct(2), indirect(2),
338  						double_indirect(1) node id */
339  } __packed;
340  
341  struct direct_node {
342  	__le32 addr[DEF_ADDRS_PER_BLOCK];	/* array of data block address */
343  } __packed;
344  
345  struct indirect_node {
346  	__le32 nid[NIDS_PER_BLOCK];	/* array of data block address */
347  } __packed;
348  
349  enum {
350  	COLD_BIT_SHIFT = 0,
351  	FSYNC_BIT_SHIFT,
352  	DENT_BIT_SHIFT,
353  	OFFSET_BIT_SHIFT
354  };
355  
356  #define OFFSET_BIT_MASK		GENMASK(OFFSET_BIT_SHIFT - 1, 0)
357  
358  struct f2fs_node {
359  	/* can be one of three types: inode, direct, and indirect types */
360  	union {
361  		struct f2fs_inode i;
362  		struct direct_node dn;
363  		struct indirect_node in;
364  	};
365  	struct node_footer footer;
366  } __packed;
367  
368  /*
369   * For NAT entries
370   */
371  #define NAT_ENTRY_PER_BLOCK (F2FS_BLKSIZE / sizeof(struct f2fs_nat_entry))
372  
373  struct f2fs_nat_entry {
374  	__u8 version;		/* latest version of cached nat entry */
375  	__le32 ino;		/* inode number */
376  	__le32 block_addr;	/* block address */
377  } __packed;
378  
379  struct f2fs_nat_block {
380  	struct f2fs_nat_entry entries[NAT_ENTRY_PER_BLOCK];
381  } __packed;
382  
383  /*
384   * For SIT entries
385   *
386   * A validity bitmap of 64 bytes covers 512 blocks of area. For a 4K page size,
387   * this results in a segment size of 2MB. For 16k pages, the default segment size
388   * is 8MB.
389   * Not allow to change this.
390   */
391  #define SIT_VBLOCK_MAP_SIZE 64
392  #define SIT_ENTRY_PER_BLOCK (F2FS_BLKSIZE / sizeof(struct f2fs_sit_entry))
393  
394  /*
395   * F2FS uses 4 bytes to represent block address. As a result, supported size of
396   * disk is 16 TB for a 4K page size and 64 TB for a 16K page size and it equals
397   * to 16 * 1024 * 1024 / 2 segments.
398   */
399  #define F2FS_MAX_SEGMENT       ((16 * 1024 * 1024) / 2)
400  
401  /*
402   * Note that f2fs_sit_entry->vblocks has the following bit-field information.
403   * [15:10] : allocation type such as CURSEG_XXXX_TYPE
404   * [9:0] : valid block count
405   */
406  #define SIT_VBLOCKS_SHIFT	10
407  #define SIT_VBLOCKS_MASK	((1 << SIT_VBLOCKS_SHIFT) - 1)
408  #define GET_SIT_VBLOCKS(raw_sit)				\
409  	(le16_to_cpu((raw_sit)->vblocks) & SIT_VBLOCKS_MASK)
410  #define GET_SIT_TYPE(raw_sit)					\
411  	((le16_to_cpu((raw_sit)->vblocks) & ~SIT_VBLOCKS_MASK)	\
412  	 >> SIT_VBLOCKS_SHIFT)
413  
414  struct f2fs_sit_entry {
415  	__le16 vblocks;				/* reference above */
416  	__u8 valid_map[SIT_VBLOCK_MAP_SIZE];	/* bitmap for valid blocks */
417  	__le64 mtime;				/* segment age for cleaning */
418  } __packed;
419  
420  struct f2fs_sit_block {
421  	struct f2fs_sit_entry entries[SIT_ENTRY_PER_BLOCK];
422  } __packed;
423  
424  /*
425   * For segment summary
426   *
427   * One summary block with 4KB size contains exactly 512 summary entries, which
428   * represents exactly one segment with 2MB size.
429   * Similarly, in the case of block with 16KB size, it represents one segment with 8MB size.
430   * Not allow to change the basic units.
431   *
432   * NOTE: For initializing fields, you must use set_summary
433   *
434   * - If data page, nid represents dnode's nid
435   * - If node page, nid represents the node page's nid.
436   *
437   * The ofs_in_node is used by only data page. It represents offset
438   * from node's page's beginning to get a data block address.
439   * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
440   */
441  #define ENTRIES_IN_SUM		(F2FS_BLKSIZE / 8)
442  #define	SUMMARY_SIZE		(7)	/* sizeof(struct f2fs_summary) */
443  #define	SUM_FOOTER_SIZE		(5)	/* sizeof(struct summary_footer) */
444  #define SUM_ENTRY_SIZE		(SUMMARY_SIZE * ENTRIES_IN_SUM)
445  
446  /* a summary entry for a block in a segment */
447  struct f2fs_summary {
448  	__le32 nid;		/* parent node id */
449  	union {
450  		__u8 reserved[3];
451  		struct {
452  			__u8 version;		/* node version number */
453  			__le16 ofs_in_node;	/* block index in parent node */
454  		} __packed;
455  	};
456  } __packed;
457  
458  /* summary block type, node or data, is stored to the summary_footer */
459  #define SUM_TYPE_NODE		(1)
460  #define SUM_TYPE_DATA		(0)
461  
462  struct summary_footer {
463  	unsigned char entry_type;	/* SUM_TYPE_XXX */
464  	__le32 check_sum;		/* summary checksum */
465  } __packed;
466  
467  #define SUM_JOURNAL_SIZE	(F2FS_BLKSIZE - SUM_FOOTER_SIZE -\
468  				SUM_ENTRY_SIZE)
469  #define NAT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
470  				sizeof(struct nat_journal_entry))
471  #define NAT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
472  				sizeof(struct nat_journal_entry))
473  #define SIT_JOURNAL_ENTRIES	((SUM_JOURNAL_SIZE - 2) /\
474  				sizeof(struct sit_journal_entry))
475  #define SIT_JOURNAL_RESERVED	((SUM_JOURNAL_SIZE - 2) %\
476  				sizeof(struct sit_journal_entry))
477  
478  /* Reserved area should make size of f2fs_extra_info equals to
479   * that of nat_journal and sit_journal.
480   */
481  #define EXTRA_INFO_RESERVED	(SUM_JOURNAL_SIZE - 2 - 8)
482  
483  /*
484   * frequently updated NAT/SIT entries can be stored in the spare area in
485   * summary blocks
486   */
487  enum {
488  	NAT_JOURNAL = 0,
489  	SIT_JOURNAL
490  };
491  
492  struct nat_journal_entry {
493  	__le32 nid;
494  	struct f2fs_nat_entry ne;
495  } __packed;
496  
497  struct nat_journal {
498  	struct nat_journal_entry entries[NAT_JOURNAL_ENTRIES];
499  	__u8 reserved[NAT_JOURNAL_RESERVED];
500  } __packed;
501  
502  struct sit_journal_entry {
503  	__le32 segno;
504  	struct f2fs_sit_entry se;
505  } __packed;
506  
507  struct sit_journal {
508  	struct sit_journal_entry entries[SIT_JOURNAL_ENTRIES];
509  	__u8 reserved[SIT_JOURNAL_RESERVED];
510  } __packed;
511  
512  struct f2fs_extra_info {
513  	__le64 kbytes_written;
514  	__u8 reserved[EXTRA_INFO_RESERVED];
515  } __packed;
516  
517  struct f2fs_journal {
518  	union {
519  		__le16 n_nats;
520  		__le16 n_sits;
521  	};
522  	/* spare area is used by NAT or SIT journals or extra info */
523  	union {
524  		struct nat_journal nat_j;
525  		struct sit_journal sit_j;
526  		struct f2fs_extra_info info;
527  	};
528  } __packed;
529  
530  /* Block-sized summary block structure */
531  struct f2fs_summary_block {
532  	struct f2fs_summary entries[ENTRIES_IN_SUM];
533  	struct f2fs_journal journal;
534  	struct summary_footer footer;
535  } __packed;
536  
537  /*
538   * For directory operations
539   */
540  #define F2FS_DOT_HASH		0
541  #define F2FS_DDOT_HASH		F2FS_DOT_HASH
542  #define F2FS_MAX_HASH		(~((0x3ULL) << 62))
543  #define F2FS_HASH_COL_BIT	((0x1ULL) << 63)
544  
545  typedef __le32	f2fs_hash_t;
546  
547  /* One directory entry slot covers 8bytes-long file name */
548  #define F2FS_SLOT_LEN		8
549  #define F2FS_SLOT_LEN_BITS	3
550  
551  #define GET_DENTRY_SLOTS(x) (((x) + F2FS_SLOT_LEN - 1) >> F2FS_SLOT_LEN_BITS)
552  
553  /* MAX level for dir lookup */
554  #define MAX_DIR_HASH_DEPTH	63
555  
556  /* MAX buckets in one level of dir */
557  #define MAX_DIR_BUCKETS		BIT((MAX_DIR_HASH_DEPTH / 2) - 1)
558  
559  /*
560   * space utilization of regular dentry and inline dentry (w/o extra reservation)
561   * when block size is 4KB.
562   *		regular dentry		inline dentry (def)	inline dentry (min)
563   * bitmap	1 * 27 = 27		1 * 23 = 23		1 * 1 = 1
564   * reserved	1 * 3 = 3		1 * 7 = 7		1 * 1 = 1
565   * dentry	11 * 214 = 2354		11 * 182 = 2002		11 * 2 = 22
566   * filename	8 * 214 = 1712		8 * 182 = 1456		8 * 2 = 16
567   * total	4096			3488			40
568   *
569   * Note: there are more reserved space in inline dentry than in regular
570   * dentry, when converting inline dentry we should handle this carefully.
571   */
572  
573  /* the number of dentry in a block */
574  #define NR_DENTRY_IN_BLOCK	((BITS_PER_BYTE * F2FS_BLKSIZE) / \
575  					((SIZE_OF_DIR_ENTRY + F2FS_SLOT_LEN) * BITS_PER_BYTE + 1))
576  #define SIZE_OF_DIR_ENTRY	11	/* by byte */
577  #define SIZE_OF_DENTRY_BITMAP	((NR_DENTRY_IN_BLOCK + BITS_PER_BYTE - 1) / \
578  					BITS_PER_BYTE)
579  #define SIZE_OF_RESERVED	(F2FS_BLKSIZE - ((SIZE_OF_DIR_ENTRY + \
580  				F2FS_SLOT_LEN) * \
581  				NR_DENTRY_IN_BLOCK + SIZE_OF_DENTRY_BITMAP))
582  #define MIN_INLINE_DENTRY_SIZE		40	/* just include '.' and '..' entries */
583  
584  /* One directory entry slot representing F2FS_SLOT_LEN-sized file name */
585  struct f2fs_dir_entry {
586  	__le32 hash_code;	/* hash code of file name */
587  	__le32 ino;		/* inode number */
588  	__le16 name_len;	/* length of file name */
589  	__u8 file_type;		/* file type */
590  } __packed;
591  
592  /* Block-sized directory entry block */
593  struct f2fs_dentry_block {
594  	/* validity bitmap for directory entries in each block */
595  	__u8 dentry_bitmap[SIZE_OF_DENTRY_BITMAP];
596  	__u8 reserved[SIZE_OF_RESERVED];
597  	struct f2fs_dir_entry dentry[NR_DENTRY_IN_BLOCK];
598  	__u8 filename[NR_DENTRY_IN_BLOCK][F2FS_SLOT_LEN];
599  } __packed;
600  
601  #define	F2FS_DEF_PROJID		0	/* default project ID */
602  
603  #endif  /* _LINUX_F2FS_FS_H */
604