~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/fs/ext2/ext2.h

Version: ~ [ linux-5.13-rc5 ] ~ [ linux-5.12.9 ] ~ [ linux-5.11.22 ] ~ [ linux-5.10.42 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.124 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.193 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.235 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.271 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.271 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.18.140 ] ~ [ linux-3.16.85 ] ~ [ linux-3.14.79 ] ~ [ linux-3.12.74 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /*
  2  * Copyright (C) 1992, 1993, 1994, 1995
  3  * Remy Card (card@masi.ibp.fr)
  4  * Laboratoire MASI - Institut Blaise Pascal
  5  * Universite Pierre et Marie Curie (Paris VI)
  6  *
  7  *  from
  8  *
  9  *  linux/include/linux/minix_fs.h
 10  *
 11  *  Copyright (C) 1991, 1992  Linus Torvalds
 12  */
 13 #include <linux/fs.h>
 14 #include <linux/ext2_fs.h>
 15 #include <linux/blockgroup_lock.h>
 16 #include <linux/percpu_counter.h>
 17 #include <linux/rbtree.h>
 18 
 19 /* XXX Here for now... not interested in restructing headers JUST now */
 20 
 21 /* data type for block offset of block group */
 22 typedef int ext2_grpblk_t;
 23 
 24 /* data type for filesystem-wide blocks number */
 25 typedef unsigned long ext2_fsblk_t;
 26 
 27 #define E2FSBLK "%lu"
 28 
 29 struct ext2_reserve_window {
 30         ext2_fsblk_t            _rsv_start;     /* First byte reserved */
 31         ext2_fsblk_t            _rsv_end;       /* Last byte reserved or 0 */
 32 };
 33 
 34 struct ext2_reserve_window_node {
 35         struct rb_node          rsv_node;
 36         __u32                   rsv_goal_size;
 37         __u32                   rsv_alloc_hit;
 38         struct ext2_reserve_window      rsv_window;
 39 };
 40 
 41 struct ext2_block_alloc_info {
 42         /* information about reservation window */
 43         struct ext2_reserve_window_node rsv_window_node;
 44         /*
 45          * was i_next_alloc_block in ext2_inode_info
 46          * is the logical (file-relative) number of the
 47          * most-recently-allocated block in this file.
 48          * We use this for detecting linearly ascending allocation requests.
 49          */
 50         __u32                   last_alloc_logical_block;
 51         /*
 52          * Was i_next_alloc_goal in ext2_inode_info
 53          * is the *physical* companion to i_next_alloc_block.
 54          * it the the physical block number of the block which was most-recentl
 55          * allocated to this file.  This give us the goal (target) for the next
 56          * allocation when we detect linearly ascending requests.
 57          */
 58         ext2_fsblk_t            last_alloc_physical_block;
 59 };
 60 
 61 #define rsv_start rsv_window._rsv_start
 62 #define rsv_end rsv_window._rsv_end
 63 
 64 struct mb_cache;
 65 
 66 /*
 67  * second extended-fs super-block data in memory
 68  */
 69 struct ext2_sb_info {
 70         unsigned long s_frag_size;      /* Size of a fragment in bytes */
 71         unsigned long s_frags_per_block;/* Number of fragments per block */
 72         unsigned long s_inodes_per_block;/* Number of inodes per block */
 73         unsigned long s_frags_per_group;/* Number of fragments in a group */
 74         unsigned long s_blocks_per_group;/* Number of blocks in a group */
 75         unsigned long s_inodes_per_group;/* Number of inodes in a group */
 76         unsigned long s_itb_per_group;  /* Number of inode table blocks per group */
 77         unsigned long s_gdb_count;      /* Number of group descriptor blocks */
 78         unsigned long s_desc_per_block; /* Number of group descriptors per block */
 79         unsigned long s_groups_count;   /* Number of groups in the fs */
 80         unsigned long s_overhead_last;  /* Last calculated overhead */
 81         unsigned long s_blocks_last;    /* Last seen block count */
 82         struct buffer_head * s_sbh;     /* Buffer containing the super block */
 83         struct ext2_super_block * s_es; /* Pointer to the super block in the buffer */
 84         struct buffer_head ** s_group_desc;
 85         unsigned long  s_mount_opt;
 86         unsigned long s_sb_block;
 87         kuid_t s_resuid;
 88         kgid_t s_resgid;
 89         unsigned short s_mount_state;
 90         unsigned short s_pad;
 91         int s_addr_per_block_bits;
 92         int s_desc_per_block_bits;
 93         int s_inode_size;
 94         int s_first_ino;
 95         spinlock_t s_next_gen_lock;
 96         u32 s_next_generation;
 97         unsigned long s_dir_count;
 98         u8 *s_debts;
 99         struct percpu_counter s_freeblocks_counter;
100         struct percpu_counter s_freeinodes_counter;
101         struct percpu_counter s_dirs_counter;
102         struct blockgroup_lock *s_blockgroup_lock;
103         /* root of the per fs reservation window tree */
104         spinlock_t s_rsv_window_lock;
105         struct rb_root s_rsv_window_root;
106         struct ext2_reserve_window_node s_rsv_window_head;
107         /*
108          * s_lock protects against concurrent modifications of s_mount_state,
109          * s_blocks_last, s_overhead_last and the content of superblock's
110          * buffer pointed to by sbi->s_es.
111          *
112          * Note: It is used in ext2_show_options() to provide a consistent view
113          * of the mount options.
114          */
115         spinlock_t s_lock;
116         struct mb_cache *s_ea_block_cache;
117 };
118 
119 static inline spinlock_t *
120 sb_bgl_lock(struct ext2_sb_info *sbi, unsigned int block_group)
121 {
122         return bgl_lock_ptr(sbi->s_blockgroup_lock, block_group);
123 }
124 
125 /*
126  * Define EXT2FS_DEBUG to produce debug messages
127  */
128 #undef EXT2FS_DEBUG
129 
130 /*
131  * Define EXT2_RESERVATION to reserve data blocks for expanding files
132  */
133 #define EXT2_DEFAULT_RESERVE_BLOCKS     8
134 /*max window size: 1024(direct blocks) + 3([t,d]indirect blocks) */
135 #define EXT2_MAX_RESERVE_BLOCKS         1027
136 #define EXT2_RESERVE_WINDOW_NOT_ALLOCATED 0
137 /*
138  * The second extended file system version
139  */
140 #define EXT2FS_DATE             "95/08/09"
141 #define EXT2FS_VERSION          "0.5b"
142 
143 /*
144  * Debug code
145  */
146 #ifdef EXT2FS_DEBUG
147 #       define ext2_debug(f, a...)      { \
148                                         printk ("EXT2-fs DEBUG (%s, %d): %s:", \
149                                                 __FILE__, __LINE__, __func__); \
150                                         printk (f, ## a); \
151                                         }
152 #else
153 #       define ext2_debug(f, a...)      /**/
154 #endif
155 
156 /*
157  * Special inode numbers
158  */
159 #define EXT2_BAD_INO             1      /* Bad blocks inode */
160 #define EXT2_ROOT_INO            2      /* Root inode */
161 #define EXT2_BOOT_LOADER_INO     5      /* Boot loader inode */
162 #define EXT2_UNDEL_DIR_INO       6      /* Undelete directory inode */
163 
164 /* First non-reserved inode for old ext2 filesystems */
165 #define EXT2_GOOD_OLD_FIRST_INO 11
166 
167 static inline struct ext2_sb_info *EXT2_SB(struct super_block *sb)
168 {
169         return sb->s_fs_info;
170 }
171 
172 /*
173  * Macro-instructions used to manage several block sizes
174  */
175 #define EXT2_MIN_BLOCK_SIZE             1024
176 #define EXT2_MAX_BLOCK_SIZE             4096
177 #define EXT2_MIN_BLOCK_LOG_SIZE           10
178 #define EXT2_BLOCK_SIZE(s)              ((s)->s_blocksize)
179 #define EXT2_ADDR_PER_BLOCK(s)          (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
180 #define EXT2_BLOCK_SIZE_BITS(s)         ((s)->s_blocksize_bits)
181 #define EXT2_ADDR_PER_BLOCK_BITS(s)     (EXT2_SB(s)->s_addr_per_block_bits)
182 #define EXT2_INODE_SIZE(s)              (EXT2_SB(s)->s_inode_size)
183 #define EXT2_FIRST_INO(s)               (EXT2_SB(s)->s_first_ino)
184 
185 /*
186  * Macro-instructions used to manage fragments
187  */
188 #define EXT2_MIN_FRAG_SIZE              1024
189 #define EXT2_MAX_FRAG_SIZE              4096
190 #define EXT2_MIN_FRAG_LOG_SIZE            10
191 #define EXT2_FRAG_SIZE(s)               (EXT2_SB(s)->s_frag_size)
192 #define EXT2_FRAGS_PER_BLOCK(s)         (EXT2_SB(s)->s_frags_per_block)
193 
194 /*
195  * Structure of a blocks group descriptor
196  */
197 struct ext2_group_desc
198 {
199         __le32  bg_block_bitmap;                /* Blocks bitmap block */
200         __le32  bg_inode_bitmap;                /* Inodes bitmap block */
201         __le32  bg_inode_table;         /* Inodes table block */
202         __le16  bg_free_blocks_count;   /* Free blocks count */
203         __le16  bg_free_inodes_count;   /* Free inodes count */
204         __le16  bg_used_dirs_count;     /* Directories count */
205         __le16  bg_pad;
206         __le32  bg_reserved[3];
207 };
208 
209 /*
210  * Macro-instructions used to manage group descriptors
211  */
212 #define EXT2_BLOCKS_PER_GROUP(s)        (EXT2_SB(s)->s_blocks_per_group)
213 #define EXT2_DESC_PER_BLOCK(s)          (EXT2_SB(s)->s_desc_per_block)
214 #define EXT2_INODES_PER_GROUP(s)        (EXT2_SB(s)->s_inodes_per_group)
215 #define EXT2_DESC_PER_BLOCK_BITS(s)     (EXT2_SB(s)->s_desc_per_block_bits)
216 
217 /*
218  * Constants relative to the data blocks
219  */
220 #define EXT2_NDIR_BLOCKS                12
221 #define EXT2_IND_BLOCK                  EXT2_NDIR_BLOCKS
222 #define EXT2_DIND_BLOCK                 (EXT2_IND_BLOCK + 1)
223 #define EXT2_TIND_BLOCK                 (EXT2_DIND_BLOCK + 1)
224 #define EXT2_N_BLOCKS                   (EXT2_TIND_BLOCK + 1)
225 
226 /*
227  * Inode flags (GETFLAGS/SETFLAGS)
228  */
229 #define EXT2_SECRM_FL                   FS_SECRM_FL     /* Secure deletion */
230 #define EXT2_UNRM_FL                    FS_UNRM_FL      /* Undelete */
231 #define EXT2_COMPR_FL                   FS_COMPR_FL     /* Compress file */
232 #define EXT2_SYNC_FL                    FS_SYNC_FL      /* Synchronous updates */
233 #define EXT2_IMMUTABLE_FL               FS_IMMUTABLE_FL /* Immutable file */
234 #define EXT2_APPEND_FL                  FS_APPEND_FL    /* writes to file may only append */
235 #define EXT2_NODUMP_FL                  FS_NODUMP_FL    /* do not dump file */
236 #define EXT2_NOATIME_FL                 FS_NOATIME_FL   /* do not update atime */
237 /* Reserved for compression usage... */
238 #define EXT2_DIRTY_FL                   FS_DIRTY_FL
239 #define EXT2_COMPRBLK_FL                FS_COMPRBLK_FL  /* One or more compressed clusters */
240 #define EXT2_NOCOMP_FL                  FS_NOCOMP_FL    /* Don't compress */
241 #define EXT2_ECOMPR_FL                  FS_ECOMPR_FL    /* Compression error */
242 /* End compression flags --- maybe not all used */      
243 #define EXT2_BTREE_FL                   FS_BTREE_FL     /* btree format dir */
244 #define EXT2_INDEX_FL                   FS_INDEX_FL     /* hash-indexed directory */
245 #define EXT2_IMAGIC_FL                  FS_IMAGIC_FL    /* AFS directory */
246 #define EXT2_JOURNAL_DATA_FL            FS_JOURNAL_DATA_FL /* Reserved for ext3 */
247 #define EXT2_NOTAIL_FL                  FS_NOTAIL_FL    /* file tail should not be merged */
248 #define EXT2_DIRSYNC_FL                 FS_DIRSYNC_FL   /* dirsync behaviour (directories only) */
249 #define EXT2_TOPDIR_FL                  FS_TOPDIR_FL    /* Top of directory hierarchies*/
250 #define EXT2_RESERVED_FL                FS_RESERVED_FL  /* reserved for ext2 lib */
251 
252 #define EXT2_FL_USER_VISIBLE            FS_FL_USER_VISIBLE      /* User visible flags */
253 #define EXT2_FL_USER_MODIFIABLE         FS_FL_USER_MODIFIABLE   /* User modifiable flags */
254 
255 /* Flags that should be inherited by new inodes from their parent. */
256 #define EXT2_FL_INHERITED (EXT2_SECRM_FL | EXT2_UNRM_FL | EXT2_COMPR_FL |\
257                            EXT2_SYNC_FL | EXT2_NODUMP_FL |\
258                            EXT2_NOATIME_FL | EXT2_COMPRBLK_FL |\
259                            EXT2_NOCOMP_FL | EXT2_JOURNAL_DATA_FL |\
260                            EXT2_NOTAIL_FL | EXT2_DIRSYNC_FL)
261 
262 /* Flags that are appropriate for regular files (all but dir-specific ones). */
263 #define EXT2_REG_FLMASK (~(EXT2_DIRSYNC_FL | EXT2_TOPDIR_FL))
264 
265 /* Flags that are appropriate for non-directories/regular files. */
266 #define EXT2_OTHER_FLMASK (EXT2_NODUMP_FL | EXT2_NOATIME_FL)
267 
268 /* Mask out flags that are inappropriate for the given type of inode. */
269 static inline __u32 ext2_mask_flags(umode_t mode, __u32 flags)
270 {
271         if (S_ISDIR(mode))
272                 return flags;
273         else if (S_ISREG(mode))
274                 return flags & EXT2_REG_FLMASK;
275         else
276                 return flags & EXT2_OTHER_FLMASK;
277 }
278 
279 /*
280  * ioctl commands
281  */
282 #define EXT2_IOC_GETFLAGS               FS_IOC_GETFLAGS
283 #define EXT2_IOC_SETFLAGS               FS_IOC_SETFLAGS
284 #define EXT2_IOC_GETVERSION             FS_IOC_GETVERSION
285 #define EXT2_IOC_SETVERSION             FS_IOC_SETVERSION
286 #define EXT2_IOC_GETRSVSZ               _IOR('f', 5, long)
287 #define EXT2_IOC_SETRSVSZ               _IOW('f', 6, long)
288 
289 /*
290  * ioctl commands in 32 bit emulation
291  */
292 #define EXT2_IOC32_GETFLAGS             FS_IOC32_GETFLAGS
293 #define EXT2_IOC32_SETFLAGS             FS_IOC32_SETFLAGS
294 #define EXT2_IOC32_GETVERSION           FS_IOC32_GETVERSION
295 #define EXT2_IOC32_SETVERSION           FS_IOC32_SETVERSION
296 
297 /*
298  * Structure of an inode on the disk
299  */
300 struct ext2_inode {
301         __le16  i_mode;         /* File mode */
302         __le16  i_uid;          /* Low 16 bits of Owner Uid */
303         __le32  i_size;         /* Size in bytes */
304         __le32  i_atime;        /* Access time */
305         __le32  i_ctime;        /* Creation time */
306         __le32  i_mtime;        /* Modification time */
307         __le32  i_dtime;        /* Deletion Time */
308         __le16  i_gid;          /* Low 16 bits of Group Id */
309         __le16  i_links_count;  /* Links count */
310         __le32  i_blocks;       /* Blocks count */
311         __le32  i_flags;        /* File flags */
312         union {
313                 struct {
314                         __le32  l_i_reserved1;
315                 } linux1;
316                 struct {
317                         __le32  h_i_translator;
318                 } hurd1;
319                 struct {
320                         __le32  m_i_reserved1;
321                 } masix1;
322         } osd1;                         /* OS dependent 1 */
323         __le32  i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
324         __le32  i_generation;   /* File version (for NFS) */
325         __le32  i_file_acl;     /* File ACL */
326         __le32  i_dir_acl;      /* Directory ACL */
327         __le32  i_faddr;        /* Fragment address */
328         union {
329                 struct {
330                         __u8    l_i_frag;       /* Fragment number */
331                         __u8    l_i_fsize;      /* Fragment size */
332                         __u16   i_pad1;
333                         __le16  l_i_uid_high;   /* these 2 fields    */
334                         __le16  l_i_gid_high;   /* were reserved2[0] */
335                         __u32   l_i_reserved2;
336                 } linux2;
337                 struct {
338                         __u8    h_i_frag;       /* Fragment number */
339                         __u8    h_i_fsize;      /* Fragment size */
340                         __le16  h_i_mode_high;
341                         __le16  h_i_uid_high;
342                         __le16  h_i_gid_high;
343                         __le32  h_i_author;
344                 } hurd2;
345                 struct {
346                         __u8    m_i_frag;       /* Fragment number */
347                         __u8    m_i_fsize;      /* Fragment size */
348                         __u16   m_pad1;
349                         __u32   m_i_reserved2[2];
350                 } masix2;
351         } osd2;                         /* OS dependent 2 */
352 };
353 
354 #define i_size_high     i_dir_acl
355 
356 #define i_reserved1     osd1.linux1.l_i_reserved1
357 #define i_frag          osd2.linux2.l_i_frag
358 #define i_fsize         osd2.linux2.l_i_fsize
359 #define i_uid_low       i_uid
360 #define i_gid_low       i_gid
361 #define i_uid_high      osd2.linux2.l_i_uid_high
362 #define i_gid_high      osd2.linux2.l_i_gid_high
363 #define i_reserved2     osd2.linux2.l_i_reserved2
364 
365 /*
366  * File system states
367  */
368 #define EXT2_VALID_FS                   0x0001  /* Unmounted cleanly */
369 #define EXT2_ERROR_FS                   0x0002  /* Errors detected */
370 #define EFSCORRUPTED                    EUCLEAN /* Filesystem is corrupted */
371 
372 /*
373  * Mount flags
374  */
375 #define EXT2_MOUNT_CHECK                0x000001  /* Do mount-time checks */
376 #define EXT2_MOUNT_OLDALLOC             0x000002  /* Don't use the new Orlov allocator */
377 #define EXT2_MOUNT_GRPID                0x000004  /* Create files with directory's group */
378 #define EXT2_MOUNT_DEBUG                0x000008  /* Some debugging messages */
379 #define EXT2_MOUNT_ERRORS_CONT          0x000010  /* Continue on errors */
380 #define EXT2_MOUNT_ERRORS_RO            0x000020  /* Remount fs ro on errors */
381 #define EXT2_MOUNT_ERRORS_PANIC         0x000040  /* Panic on errors */
382 #define EXT2_MOUNT_MINIX_DF             0x000080  /* Mimics the Minix statfs */
383 #define EXT2_MOUNT_NOBH                 0x000100  /* No buffer_heads */
384 #define EXT2_MOUNT_NO_UID32             0x000200  /* Disable 32-bit UIDs */
385 #define EXT2_MOUNT_XATTR_USER           0x004000  /* Extended user attributes */
386 #define EXT2_MOUNT_POSIX_ACL            0x008000  /* POSIX Access Control Lists */
387 #define EXT2_MOUNT_XIP                  0x010000  /* Obsolete, use DAX */
388 #define EXT2_MOUNT_USRQUOTA             0x020000  /* user quota */
389 #define EXT2_MOUNT_GRPQUOTA             0x040000  /* group quota */
390 #define EXT2_MOUNT_RESERVATION          0x080000  /* Preallocation */
391 #ifdef CONFIG_FS_DAX
392 #define EXT2_MOUNT_DAX                  0x100000  /* Direct Access */
393 #else
394 #define EXT2_MOUNT_DAX                  0
395 #endif
396 
397 
398 #define clear_opt(o, opt)               o &= ~EXT2_MOUNT_##opt
399 #define set_opt(o, opt)                 o |= EXT2_MOUNT_##opt
400 #define test_opt(sb, opt)               (EXT2_SB(sb)->s_mount_opt & \
401                                          EXT2_MOUNT_##opt)
402 /*
403  * Maximal mount counts between two filesystem checks
404  */
405 #define EXT2_DFL_MAX_MNT_COUNT          20      /* Allow 20 mounts */
406 #define EXT2_DFL_CHECKINTERVAL          0       /* Don't use interval check */
407 
408 /*
409  * Behaviour when detecting errors
410  */
411 #define EXT2_ERRORS_CONTINUE            1       /* Continue execution */
412 #define EXT2_ERRORS_RO                  2       /* Remount fs read-only */
413 #define EXT2_ERRORS_PANIC               3       /* Panic */
414 #define EXT2_ERRORS_DEFAULT             EXT2_ERRORS_CONTINUE
415 
416 /*
417  * Structure of the super block
418  */
419 struct ext2_super_block {
420         __le32  s_inodes_count;         /* Inodes count */
421         __le32  s_blocks_count;         /* Blocks count */
422         __le32  s_r_blocks_count;       /* Reserved blocks count */
423         __le32  s_free_blocks_count;    /* Free blocks count */
424         __le32  s_free_inodes_count;    /* Free inodes count */
425         __le32  s_first_data_block;     /* First Data Block */
426         __le32  s_log_block_size;       /* Block size */
427         __le32  s_log_frag_size;        /* Fragment size */
428         __le32  s_blocks_per_group;     /* # Blocks per group */
429         __le32  s_frags_per_group;      /* # Fragments per group */
430         __le32  s_inodes_per_group;     /* # Inodes per group */
431         __le32  s_mtime;                /* Mount time */
432         __le32  s_wtime;                /* Write time */
433         __le16  s_mnt_count;            /* Mount count */
434         __le16  s_max_mnt_count;        /* Maximal mount count */
435         __le16  s_magic;                /* Magic signature */
436         __le16  s_state;                /* File system state */
437         __le16  s_errors;               /* Behaviour when detecting errors */
438         __le16  s_minor_rev_level;      /* minor revision level */
439         __le32  s_lastcheck;            /* time of last check */
440         __le32  s_checkinterval;        /* max. time between checks */
441         __le32  s_creator_os;           /* OS */
442         __le32  s_rev_level;            /* Revision level */
443         __le16  s_def_resuid;           /* Default uid for reserved blocks */
444         __le16  s_def_resgid;           /* Default gid for reserved blocks */
445         /*
446          * These fields are for EXT2_DYNAMIC_REV superblocks only.
447          *
448          * Note: the difference between the compatible feature set and
449          * the incompatible feature set is that if there is a bit set
450          * in the incompatible feature set that the kernel doesn't
451          * know about, it should refuse to mount the filesystem.
452          * 
453          * e2fsck's requirements are more strict; if it doesn't know
454          * about a feature in either the compatible or incompatible
455          * feature set, it must abort and not try to meddle with
456          * things it doesn't understand...
457          */
458         __le32  s_first_ino;            /* First non-reserved inode */
459         __le16   s_inode_size;          /* size of inode structure */
460         __le16  s_block_group_nr;       /* block group # of this superblock */
461         __le32  s_feature_compat;       /* compatible feature set */
462         __le32  s_feature_incompat;     /* incompatible feature set */
463         __le32  s_feature_ro_compat;    /* readonly-compatible feature set */
464         __u8    s_uuid[16];             /* 128-bit uuid for volume */
465         char    s_volume_name[16];      /* volume name */
466         char    s_last_mounted[64];     /* directory where last mounted */
467         __le32  s_algorithm_usage_bitmap; /* For compression */
468         /*
469          * Performance hints.  Directory preallocation should only
470          * happen if the EXT2_COMPAT_PREALLOC flag is on.
471          */
472         __u8    s_prealloc_blocks;      /* Nr of blocks to try to preallocate*/
473         __u8    s_prealloc_dir_blocks;  /* Nr to preallocate for dirs */
474         __u16   s_padding1;
475         /*
476          * Journaling support valid if EXT3_FEATURE_COMPAT_HAS_JOURNAL set.
477          */
478         __u8    s_journal_uuid[16];     /* uuid of journal superblock */
479         __u32   s_journal_inum;         /* inode number of journal file */
480         __u32   s_journal_dev;          /* device number of journal file */
481         __u32   s_last_orphan;          /* start of list of inodes to delete */
482         __u32   s_hash_seed[4];         /* HTREE hash seed */
483         __u8    s_def_hash_version;     /* Default hash version to use */
484         __u8    s_reserved_char_pad;
485         __u16   s_reserved_word_pad;
486         __le32  s_default_mount_opts;
487         __le32  s_first_meta_bg;        /* First metablock block group */
488         __u32   s_reserved[190];        /* Padding to the end of the block */
489 };
490 
491 /*
492  * Codes for operating systems
493  */
494 #define EXT2_OS_LINUX           0
495 #define EXT2_OS_HURD            1
496 #define EXT2_OS_MASIX           2
497 #define EXT2_OS_FREEBSD         3
498 #define EXT2_OS_LITES           4
499 
500 /*
501  * Revision levels
502  */
503 #define EXT2_GOOD_OLD_REV       0       /* The good old (original) format */
504 #define EXT2_DYNAMIC_REV        1       /* V2 format w/ dynamic inode sizes */
505 
506 #define EXT2_CURRENT_REV        EXT2_GOOD_OLD_REV
507 #define EXT2_MAX_SUPP_REV       EXT2_DYNAMIC_REV
508 
509 #define EXT2_GOOD_OLD_INODE_SIZE 128
510 
511 /*
512  * Feature set definitions
513  */
514 
515 #define EXT2_HAS_COMPAT_FEATURE(sb,mask)                        \
516         ( EXT2_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )
517 #define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask)                     \
518         ( EXT2_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )
519 #define EXT2_HAS_INCOMPAT_FEATURE(sb,mask)                      \
520         ( EXT2_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )
521 #define EXT2_SET_COMPAT_FEATURE(sb,mask)                        \
522         EXT2_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)
523 #define EXT2_SET_RO_COMPAT_FEATURE(sb,mask)                     \
524         EXT2_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)
525 #define EXT2_SET_INCOMPAT_FEATURE(sb,mask)                      \
526         EXT2_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)
527 #define EXT2_CLEAR_COMPAT_FEATURE(sb,mask)                      \
528         EXT2_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)
529 #define EXT2_CLEAR_RO_COMPAT_FEATURE(sb,mask)                   \
530         EXT2_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)
531 #define EXT2_CLEAR_INCOMPAT_FEATURE(sb,mask)                    \
532         EXT2_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)
533 
534 #define EXT2_FEATURE_COMPAT_DIR_PREALLOC        0x0001
535 #define EXT2_FEATURE_COMPAT_IMAGIC_INODES       0x0002
536 #define EXT3_FEATURE_COMPAT_HAS_JOURNAL         0x0004
537 #define EXT2_FEATURE_COMPAT_EXT_ATTR            0x0008
538 #define EXT2_FEATURE_COMPAT_RESIZE_INO          0x0010
539 #define EXT2_FEATURE_COMPAT_DIR_INDEX           0x0020
540 #define EXT2_FEATURE_COMPAT_ANY                 0xffffffff
541 
542 #define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER     0x0001
543 #define EXT2_FEATURE_RO_COMPAT_LARGE_FILE       0x0002
544 #define EXT2_FEATURE_RO_COMPAT_BTREE_DIR        0x0004
545 #define EXT2_FEATURE_RO_COMPAT_ANY              0xffffffff
546 
547 #define EXT2_FEATURE_INCOMPAT_COMPRESSION       0x0001
548 #define EXT2_FEATURE_INCOMPAT_FILETYPE          0x0002
549 #define EXT3_FEATURE_INCOMPAT_RECOVER           0x0004
550 #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV       0x0008
551 #define EXT2_FEATURE_INCOMPAT_META_BG           0x0010
552 #define EXT2_FEATURE_INCOMPAT_ANY               0xffffffff
553 
554 #define EXT2_FEATURE_COMPAT_SUPP        EXT2_FEATURE_COMPAT_EXT_ATTR
555 #define EXT2_FEATURE_INCOMPAT_SUPP      (EXT2_FEATURE_INCOMPAT_FILETYPE| \
556                                          EXT2_FEATURE_INCOMPAT_META_BG)
557 #define EXT2_FEATURE_RO_COMPAT_SUPP     (EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \
558                                          EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \
559                                          EXT2_FEATURE_RO_COMPAT_BTREE_DIR)
560 #define EXT2_FEATURE_RO_COMPAT_UNSUPPORTED      ~EXT2_FEATURE_RO_COMPAT_SUPP
561 #define EXT2_FEATURE_INCOMPAT_UNSUPPORTED       ~EXT2_FEATURE_INCOMPAT_SUPP
562 
563 /*
564  * Default values for user and/or group using reserved blocks
565  */
566 #define EXT2_DEF_RESUID         0
567 #define EXT2_DEF_RESGID         0
568 
569 /*
570  * Default mount options
571  */
572 #define EXT2_DEFM_DEBUG         0x0001
573 #define EXT2_DEFM_BSDGROUPS     0x0002
574 #define EXT2_DEFM_XATTR_USER    0x0004
575 #define EXT2_DEFM_ACL           0x0008
576 #define EXT2_DEFM_UID16         0x0010
577     /* Not used by ext2, but reserved for use by ext3 */
578 #define EXT3_DEFM_JMODE         0x0060 
579 #define EXT3_DEFM_JMODE_DATA    0x0020
580 #define EXT3_DEFM_JMODE_ORDERED 0x0040
581 #define EXT3_DEFM_JMODE_WBACK   0x0060
582 
583 /*
584  * Structure of a directory entry
585  */
586 
587 struct ext2_dir_entry {
588         __le32  inode;                  /* Inode number */
589         __le16  rec_len;                /* Directory entry length */
590         __le16  name_len;               /* Name length */
591         char    name[];                 /* File name, up to EXT2_NAME_LEN */
592 };
593 
594 /*
595  * The new version of the directory entry.  Since EXT2 structures are
596  * stored in intel byte order, and the name_len field could never be
597  * bigger than 255 chars, it's safe to reclaim the extra byte for the
598  * file_type field.
599  */
600 struct ext2_dir_entry_2 {
601         __le32  inode;                  /* Inode number */
602         __le16  rec_len;                /* Directory entry length */
603         __u8    name_len;               /* Name length */
604         __u8    file_type;
605         char    name[];                 /* File name, up to EXT2_NAME_LEN */
606 };
607 
608 /*
609  * Ext2 directory file types.  Only the low 3 bits are used.  The
610  * other bits are reserved for now.
611  */
612 enum {
613         EXT2_FT_UNKNOWN         = 0,
614         EXT2_FT_REG_FILE        = 1,
615         EXT2_FT_DIR             = 2,
616         EXT2_FT_CHRDEV          = 3,
617         EXT2_FT_BLKDEV          = 4,
618         EXT2_FT_FIFO            = 5,
619         EXT2_FT_SOCK            = 6,
620         EXT2_FT_SYMLINK         = 7,
621         EXT2_FT_MAX
622 };
623 
624 /*
625  * EXT2_DIR_PAD defines the directory entries boundaries
626  *
627  * NOTE: It must be a multiple of 4
628  */
629 #define EXT2_DIR_PAD                    4
630 #define EXT2_DIR_ROUND                  (EXT2_DIR_PAD - 1)
631 #define EXT2_DIR_REC_LEN(name_len)      (((name_len) + 8 + EXT2_DIR_ROUND) & \
632                                          ~EXT2_DIR_ROUND)
633 #define EXT2_MAX_REC_LEN                ((1<<16)-1)
634 
635 static inline void verify_offsets(void)
636 {
637 #define A(x,y) BUILD_BUG_ON(x != offsetof(struct ext2_super_block, y));
638         A(EXT2_SB_MAGIC_OFFSET, s_magic);
639         A(EXT2_SB_BLOCKS_OFFSET, s_blocks_count);
640         A(EXT2_SB_BSIZE_OFFSET, s_log_block_size);
641 #undef A
642 }
643 
644 /*
645  * ext2 mount options
646  */
647 struct ext2_mount_options {
648         unsigned long s_mount_opt;
649         kuid_t s_resuid;
650         kgid_t s_resgid;
651 };
652 
653 /*
654  * second extended file system inode data in memory
655  */
656 struct ext2_inode_info {
657         __le32  i_data[15];
658         __u32   i_flags;
659         __u32   i_faddr;
660         __u8    i_frag_no;
661         __u8    i_frag_size;
662         __u16   i_state;
663         __u32   i_file_acl;
664         __u32   i_dir_acl;
665         __u32   i_dtime;
666 
667         /*
668          * i_block_group is the number of the block group which contains
669          * this file's inode.  Constant across the lifetime of the inode,
670          * it is used for making block allocation decisions - we try to
671          * place a file's data blocks near its inode block, and new inodes
672          * near to their parent directory's inode.
673          */
674         __u32   i_block_group;
675 
676         /* block reservation info */
677         struct ext2_block_alloc_info *i_block_alloc_info;
678 
679         __u32   i_dir_start_lookup;
680 #ifdef CONFIG_EXT2_FS_XATTR
681         /*
682          * Extended attributes can be read independently of the main file
683          * data. Taking i_mutex even when reading would cause contention
684          * between readers of EAs and writers of regular file data, so
685          * instead we synchronize on xattr_sem when reading or changing
686          * EAs.
687          */
688         struct rw_semaphore xattr_sem;
689 #endif
690         rwlock_t i_meta_lock;
691 #ifdef CONFIG_FS_DAX
692         struct rw_semaphore dax_sem;
693 #endif
694 
695         /*
696          * truncate_mutex is for serialising ext2_truncate() against
697          * ext2_getblock().  It also protects the internals of the inode's
698          * reservation data structures: ext2_reserve_window and
699          * ext2_reserve_window_node.
700          */
701         struct mutex truncate_mutex;
702         struct inode    vfs_inode;
703         struct list_head i_orphan;      /* unlinked but open inodes */
704 #ifdef CONFIG_QUOTA
705         struct dquot *i_dquot[MAXQUOTAS];
706 #endif
707 };
708 
709 #ifdef CONFIG_FS_DAX
710 #define dax_sem_down_write(ext2_inode)  down_write(&(ext2_inode)->dax_sem)
711 #define dax_sem_up_write(ext2_inode)    up_write(&(ext2_inode)->dax_sem)
712 #else
713 #define dax_sem_down_write(ext2_inode)
714 #define dax_sem_up_write(ext2_inode)
715 #endif
716 
717 /*
718  * Inode dynamic state flags
719  */
720 #define EXT2_STATE_NEW                  0x00000001 /* inode is newly created */
721 
722 
723 /*
724  * Function prototypes
725  */
726 
727 /*
728  * Ok, these declarations are also in <linux/kernel.h> but none of the
729  * ext2 source programs needs to include it so they are duplicated here.
730  */
731 
732 static inline struct ext2_inode_info *EXT2_I(struct inode *inode)
733 {
734         return container_of(inode, struct ext2_inode_info, vfs_inode);
735 }
736 
737 /* balloc.c */
738 extern int ext2_bg_has_super(struct super_block *sb, int group);
739 extern unsigned long ext2_bg_num_gdb(struct super_block *sb, int group);
740 extern ext2_fsblk_t ext2_new_block(struct inode *, unsigned long, int *);
741 extern ext2_fsblk_t ext2_new_blocks(struct inode *, unsigned long,
742                                 unsigned long *, int *);
743 extern int ext2_data_block_valid(struct ext2_sb_info *sbi, ext2_fsblk_t start_blk,
744                                  unsigned int count);
745 extern void ext2_free_blocks (struct inode *, unsigned long,
746                               unsigned long);
747 extern unsigned long ext2_count_free_blocks (struct super_block *);
748 extern unsigned long ext2_count_dirs (struct super_block *);
749 extern void ext2_check_blocks_bitmap (struct super_block *);
750 extern struct ext2_group_desc * ext2_get_group_desc(struct super_block * sb,
751                                                     unsigned int block_group,
752                                                     struct buffer_head ** bh);
753 extern void ext2_discard_reservation (struct inode *);
754 extern int ext2_should_retry_alloc(struct super_block *sb, int *retries);
755 extern void ext2_init_block_alloc_info(struct inode *);
756 extern void ext2_rsv_window_add(struct super_block *sb, struct ext2_reserve_window_node *rsv);
757 
758 /* dir.c */
759 extern int ext2_add_link (struct dentry *, struct inode *);
760 extern ino_t ext2_inode_by_name(struct inode *, const struct qstr *);
761 extern int ext2_make_empty(struct inode *, struct inode *);
762 extern struct ext2_dir_entry_2 * ext2_find_entry (struct inode *,const struct qstr *, struct page **);
763 extern int ext2_delete_entry (struct ext2_dir_entry_2 *, struct page *);
764 extern int ext2_empty_dir (struct inode *);
765 extern struct ext2_dir_entry_2 * ext2_dotdot (struct inode *, struct page **);
766 extern void ext2_set_link(struct inode *, struct ext2_dir_entry_2 *, struct page *, struct inode *, int);
767 
768 /* ialloc.c */
769 extern struct inode * ext2_new_inode (struct inode *, umode_t, const struct qstr *);
770 extern void ext2_free_inode (struct inode *);
771 extern unsigned long ext2_count_free_inodes (struct super_block *);
772 extern void ext2_check_inodes_bitmap (struct super_block *);
773 extern unsigned long ext2_count_free (struct buffer_head *, unsigned);
774 
775 /* inode.c */
776 extern struct inode *ext2_iget (struct super_block *, unsigned long);
777 extern int ext2_write_inode (struct inode *, struct writeback_control *);
778 extern void ext2_evict_inode(struct inode *);
779 extern int ext2_get_block(struct inode *, sector_t, struct buffer_head *, int);
780 extern int ext2_setattr (struct dentry *, struct iattr *);
781 extern void ext2_set_inode_flags(struct inode *inode);
782 extern int ext2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
783                        u64 start, u64 len);
784 
785 /* ioctl.c */
786 extern long ext2_ioctl(struct file *, unsigned int, unsigned long);
787 extern long ext2_compat_ioctl(struct file *, unsigned int, unsigned long);
788 
789 /* namei.c */
790 struct dentry *ext2_get_parent(struct dentry *child);
791 
792 /* super.c */
793 extern __printf(3, 4)
794 void ext2_error(struct super_block *, const char *, const char *, ...);
795 extern __printf(3, 4)
796 void ext2_msg(struct super_block *, const char *, const char *, ...);
797 extern void ext2_update_dynamic_rev (struct super_block *sb);
798 extern void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
799                             int wait);
800 
801 /*
802  * Inodes and files operations
803  */
804 
805 /* dir.c */
806 extern const struct file_operations ext2_dir_operations;
807 
808 /* file.c */
809 extern int ext2_fsync(struct file *file, loff_t start, loff_t end,
810                       int datasync);
811 extern const struct inode_operations ext2_file_inode_operations;
812 extern const struct file_operations ext2_file_operations;
813 
814 /* inode.c */
815 extern const struct address_space_operations ext2_aops;
816 extern const struct address_space_operations ext2_nobh_aops;
817 extern const struct iomap_ops ext2_iomap_ops;
818 
819 /* namei.c */
820 extern const struct inode_operations ext2_dir_inode_operations;
821 extern const struct inode_operations ext2_special_inode_operations;
822 
823 /* symlink.c */
824 extern const struct inode_operations ext2_fast_symlink_inode_operations;
825 extern const struct inode_operations ext2_symlink_inode_operations;
826 
827 static inline ext2_fsblk_t
828 ext2_group_first_block_no(struct super_block *sb, unsigned long group_no)
829 {
830         return group_no * (ext2_fsblk_t)EXT2_BLOCKS_PER_GROUP(sb) +
831                 le32_to_cpu(EXT2_SB(sb)->s_es->s_first_data_block);
832 }
833 
834 #define ext2_set_bit    __test_and_set_bit_le
835 #define ext2_clear_bit  __test_and_clear_bit_le
836 #define ext2_test_bit   test_bit_le
837 #define ext2_find_first_zero_bit        find_first_zero_bit_le
838 #define ext2_find_next_zero_bit         find_next_zero_bit_le
839 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp