Home | History | Annotate | Download | only in linux
      1 #ifndef _LINUX_FS_H
      2 #define _LINUX_FS_H
      3 
      4 /*
      5  * This file has definitions for some important file table
      6  * structures etc.
      7  */
      8 
      9 #include <linux/limits.h>
     10 #include <linux/ioctl.h>
     11 
     12 /*
     13  * It's silly to have NR_OPEN bigger than NR_FILE, but you can change
     14  * the file limit at runtime and only root can increase the per-process
     15  * nr_file rlimit, so it's safe to set up a ridiculously high absolute
     16  * upper limit on files-per-process.
     17  *
     18  * Some programs (notably those using select()) may have to be
     19  * recompiled to take full advantage of the new limits..
     20  */
     21 
     22 /* Fixed constants first: */
     23 #undef NR_OPEN
     24 #define NR_OPEN (1024*1024)	/* Absolute upper limit on fd num */
     25 #define INR_OPEN 1024		/* Initial setting for nfile rlimits */
     26 
     27 #define BLOCK_SIZE_BITS 10
     28 #define BLOCK_SIZE (1<<BLOCK_SIZE_BITS)
     29 
     30 #define SEEK_SET	0	/* seek relative to beginning of file */
     31 #define SEEK_CUR	1	/* seek relative to current file position */
     32 #define SEEK_END	2	/* seek relative to end of file */
     33 #define SEEK_MAX	SEEK_END
     34 
     35 /* And dynamically-tunable limits and defaults: */
     36 struct files_stat_struct {
     37 	int nr_files;		/* read only */
     38 	int nr_free_files;	/* read only */
     39 	int max_files;		/* tunable */
     40 };
     41 extern struct files_stat_struct files_stat;
     42 extern int get_max_files(void);
     43 
     44 struct inodes_stat_t {
     45 	int nr_inodes;
     46 	int nr_unused;
     47 	int dummy[5];		/* padding for sysctl ABI compatibility */
     48 };
     49 extern struct inodes_stat_t inodes_stat;
     50 
     51 extern int leases_enable, lease_break_time;
     52 
     53 #ifdef CONFIG_DNOTIFY
     54 extern int dir_notify_enable;
     55 #endif
     56 
     57 #define NR_FILE  8192	/* this can well be larger on a larger system */
     58 
     59 #define MAY_EXEC 1
     60 #define MAY_WRITE 2
     61 #define MAY_READ 4
     62 #define MAY_APPEND 8
     63 
     64 #define FMODE_READ 1
     65 #define FMODE_WRITE 2
     66 
     67 /* Internal kernel extensions */
     68 #define FMODE_LSEEK	4
     69 #define FMODE_PREAD	8
     70 #define FMODE_PWRITE	FMODE_PREAD	/* These go hand in hand */
     71 
     72 /* File is being opened for execution. Primary users of this flag are
     73    distributed filesystems that can use it to achieve correct ETXTBUSY
     74    behavior for cross-node execution/opening_for_writing of files */
     75 #define FMODE_EXEC	16
     76 
     77 #define RW_MASK		1
     78 #define RWA_MASK	2
     79 #define READ 0
     80 #define WRITE 1
     81 #define READA 2		/* read-ahead  - don't block if no resources */
     82 #define SWRITE 3	/* for ll_rw_block() - wait for buffer lock */
     83 #define READ_SYNC	(READ | (1 << BIO_RW_SYNC))
     84 #define READ_META	(READ | (1 << BIO_RW_META))
     85 #define WRITE_SYNC	(WRITE | (1 << BIO_RW_SYNC))
     86 #define WRITE_BARRIER	((1 << BIO_RW) | (1 << BIO_RW_BARRIER))
     87 
     88 #define SEL_IN		1
     89 #define SEL_OUT		2
     90 #define SEL_EX		4
     91 
     92 /* public flags for file_system_type */
     93 #define FS_REQUIRES_DEV 1
     94 #define FS_BINARY_MOUNTDATA 2
     95 #define FS_HAS_SUBTYPE 4
     96 #define FS_REVAL_DOT	16384	/* Check the paths ".", ".." for staleness */
     97 #define FS_RENAME_DOES_D_MOVE	32768	/* FS will handle d_move()
     98 					 * during rename() internally.
     99 					 */
    100 
    101 /*
    102  * These are the fs-independent mount-flags: up to 32 flags are supported
    103  */
    104 #define MS_RDONLY	 1	/* Mount read-only */
    105 #define MS_NOSUID	 2	/* Ignore suid and sgid bits */
    106 #define MS_NODEV	 4	/* Disallow access to device special files */
    107 #define MS_NOEXEC	 8	/* Disallow program execution */
    108 #define MS_SYNCHRONOUS	16	/* Writes are synced at once */
    109 #define MS_REMOUNT	32	/* Alter flags of a mounted FS */
    110 #define MS_MANDLOCK	64	/* Allow mandatory locks on an FS */
    111 #define MS_DIRSYNC	128	/* Directory modifications are synchronous */
    112 #define MS_NOATIME	1024	/* Do not update access times. */
    113 #define MS_NODIRATIME	2048	/* Do not update directory access times */
    114 #define MS_BIND		4096
    115 #define MS_MOVE		8192
    116 #define MS_REC		16384
    117 #define MS_VERBOSE	32768	/* War is peace. Verbosity is silence.
    118 				   MS_VERBOSE is deprecated. */
    119 #define MS_SILENT	32768
    120 #define MS_POSIXACL	(1<<16)	/* VFS does not apply the umask */
    121 #define MS_UNBINDABLE	(1<<17)	/* change to unbindable */
    122 #define MS_PRIVATE	(1<<18)	/* change to private */
    123 #define MS_SLAVE	(1<<19)	/* change to slave */
    124 #define MS_SHARED	(1<<20)	/* change to shared */
    125 #define MS_RELATIME	(1<<21)	/* Update atime relative to mtime/ctime. */
    126 #define MS_KERNMOUNT	(1<<22) /* this is a kern_mount call */
    127 #define MS_ACTIVE	(1<<30)
    128 #define MS_NOUSER	(1<<31)
    129 
    130 /*
    131  * Superblock flags that can be altered by MS_REMOUNT
    132  */
    133 #define MS_RMT_MASK	(MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK)
    134 
    135 /*
    136  * Old magic mount flag and mask
    137  */
    138 #define MS_MGC_VAL 0xC0ED0000
    139 #define MS_MGC_MSK 0xffff0000
    140 
    141 /* Inode flags - they have nothing to superblock flags now */
    142 
    143 #define S_SYNC		1	/* Writes are synced at once */
    144 #define S_NOATIME	2	/* Do not update access times */
    145 #define S_APPEND	4	/* Append-only file */
    146 #define S_IMMUTABLE	8	/* Immutable file */
    147 #define S_DEAD		16	/* removed, but still open directory */
    148 #define S_NOQUOTA	32	/* Inode is not counted to quota */
    149 #define S_DIRSYNC	64	/* Directory modifications are synchronous */
    150 #define S_NOCMTIME	128	/* Do not update file c/mtime */
    151 #define S_SWAPFILE	256	/* Do not truncate: swapon got its bmaps */
    152 #define S_PRIVATE	512	/* Inode is fs-internal */
    153 
    154 /*
    155  * Note that nosuid etc flags are inode-specific: setting some file-system
    156  * flags just means all the inodes inherit those flags by default. It might be
    157  * possible to override it selectively if you really wanted to with some
    158  * ioctl() that is not currently implemented.
    159  *
    160  * Exception: MS_RDONLY is always applied to the entire file system.
    161  *
    162  * Unfortunately, it is possible to change a filesystems flags with it mounted
    163  * with files in use.  This means that all of the inodes will not have their
    164  * i_flags updated.  Hence, i_flags no longer inherit the superblock mount
    165  * flags, so these have to be checked separately. -- rmk (at) arm.uk.linux.org
    166  */
    167 #define __IS_FLG(inode,flg) ((inode)->i_sb->s_flags & (flg))
    168 
    169 #define IS_RDONLY(inode) ((inode)->i_sb->s_flags & MS_RDONLY)
    170 #define IS_SYNC(inode)		(__IS_FLG(inode, MS_SYNCHRONOUS) || \
    171 					((inode)->i_flags & S_SYNC))
    172 #define IS_DIRSYNC(inode)	(__IS_FLG(inode, MS_SYNCHRONOUS|MS_DIRSYNC) || \
    173 					((inode)->i_flags & (S_SYNC|S_DIRSYNC)))
    174 #define IS_MANDLOCK(inode)	__IS_FLG(inode, MS_MANDLOCK)
    175 #define IS_NOATIME(inode)   __IS_FLG(inode, MS_RDONLY|MS_NOATIME)
    176 
    177 #define IS_NOQUOTA(inode)	((inode)->i_flags & S_NOQUOTA)
    178 #define IS_APPEND(inode)	((inode)->i_flags & S_APPEND)
    179 #define IS_IMMUTABLE(inode)	((inode)->i_flags & S_IMMUTABLE)
    180 #define IS_POSIXACL(inode)	__IS_FLG(inode, MS_POSIXACL)
    181 
    182 #define IS_DEADDIR(inode)	((inode)->i_flags & S_DEAD)
    183 #define IS_NOCMTIME(inode)	((inode)->i_flags & S_NOCMTIME)
    184 #define IS_SWAPFILE(inode)	((inode)->i_flags & S_SWAPFILE)
    185 #define IS_PRIVATE(inode)	((inode)->i_flags & S_PRIVATE)
    186 
    187 /* the read-only stuff doesn't really belong here, but any other place is
    188    probably as bad and I don't want to create yet another include file. */
    189 
    190 #define BLKROSET   _IO(0x12,93)	/* set device read-only (0 = read-write) */
    191 #define BLKROGET   _IO(0x12,94)	/* get read-only status (0 = read_write) */
    192 #define BLKRRPART  _IO(0x12,95)	/* re-read partition table */
    193 #define BLKGETSIZE _IO(0x12,96)	/* return device size /512 (long *arg) */
    194 #define BLKFLSBUF  _IO(0x12,97)	/* flush buffer cache */
    195 #define BLKRASET   _IO(0x12,98)	/* set read ahead for block device */
    196 #define BLKRAGET   _IO(0x12,99)	/* get current read ahead setting */
    197 #define BLKFRASET  _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
    198 #define BLKFRAGET  _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
    199 #define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
    200 #define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
    201 #define BLKSSZGET  _IO(0x12,104)/* get block device sector size */
    202 #if 0
    203 #define BLKPG      _IO(0x12,105)/* See blkpg.h */
    204 
    205 /* Some people are morons.  Do not use sizeof! */
    206 
    207 #define BLKELVGET  _IOR(0x12,106,size_t)/* elevator get */
    208 #define BLKELVSET  _IOW(0x12,107,size_t)/* elevator set */
    209 /* This was here just to show that the number is taken -
    210    probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */
    211 #endif
    212 /* A jump here: 108-111 have been used for various private purposes. */
    213 #define BLKBSZGET  _IOR(0x12,112,size_t)
    214 #define BLKBSZSET  _IOW(0x12,113,size_t)
    215 #define BLKGETSIZE64 _IOR(0x12,114,size_t)	/* return device size in bytes (u64 *arg) */
    216 #define BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup)
    217 #define BLKTRACESTART _IO(0x12,116)
    218 #define BLKTRACESTOP _IO(0x12,117)
    219 #define BLKTRACETEARDOWN _IO(0x12,118)
    220 
    221 #define BMAP_IOCTL 1		/* obsolete - kept for compatibility */
    222 #define FIBMAP	   _IO(0x00,1)	/* bmap access */
    223 #define FIGETBSZ   _IO(0x00,2)	/* get the block size used for bmap */
    224 
    225 #define	FS_IOC_GETFLAGS			_IOR('f', 1, long)
    226 #define	FS_IOC_SETFLAGS			_IOW('f', 2, long)
    227 #define	FS_IOC_GETVERSION		_IOR('v', 1, long)
    228 #define	FS_IOC_SETVERSION		_IOW('v', 2, long)
    229 #define FS_IOC32_GETFLAGS		_IOR('f', 1, int)
    230 #define FS_IOC32_SETFLAGS		_IOW('f', 2, int)
    231 #define FS_IOC32_GETVERSION		_IOR('v', 1, int)
    232 #define FS_IOC32_SETVERSION		_IOW('v', 2, int)
    233 
    234 /*
    235  * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)
    236  */
    237 #define	FS_SECRM_FL			0x00000001 /* Secure deletion */
    238 #define	FS_UNRM_FL			0x00000002 /* Undelete */
    239 #define	FS_COMPR_FL			0x00000004 /* Compress file */
    240 #define FS_SYNC_FL			0x00000008 /* Synchronous updates */
    241 #define FS_IMMUTABLE_FL			0x00000010 /* Immutable file */
    242 #define FS_APPEND_FL			0x00000020 /* writes to file may only append */
    243 #define FS_NODUMP_FL			0x00000040 /* do not dump file */
    244 #define FS_NOATIME_FL			0x00000080 /* do not update atime */
    245 /* Reserved for compression usage... */
    246 #define FS_DIRTY_FL			0x00000100
    247 #define FS_COMPRBLK_FL			0x00000200 /* One or more compressed clusters */
    248 #define FS_NOCOMP_FL			0x00000400 /* Don't compress */
    249 #define FS_ECOMPR_FL			0x00000800 /* Compression error */
    250 /* End compression flags --- maybe not all used */
    251 #define FS_BTREE_FL			0x00001000 /* btree format dir */
    252 #define FS_INDEX_FL			0x00001000 /* hash-indexed directory */
    253 #define FS_IMAGIC_FL			0x00002000 /* AFS directory */
    254 #define FS_JOURNAL_DATA_FL		0x00004000 /* Reserved for ext3 */
    255 #define FS_NOTAIL_FL			0x00008000 /* file tail should not be merged */
    256 #define FS_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
    257 #define FS_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
    258 #define FS_EXTENT_FL			0x00080000 /* Extents */
    259 #define FS_DIRECTIO_FL			0x00100000 /* Use direct i/o */
    260 #define FS_RESERVED_FL			0x80000000 /* reserved for ext2 lib */
    261 
    262 #define FS_FL_USER_VISIBLE		0x0003DFFF /* User visible flags */
    263 #define FS_FL_USER_MODIFIABLE		0x000380FF /* User modifiable flags */
    264 
    265 
    266 #define SYNC_FILE_RANGE_WAIT_BEFORE	1
    267 #define SYNC_FILE_RANGE_WRITE		2
    268 #define SYNC_FILE_RANGE_WAIT_AFTER	4
    269 
    270 #endif /* _LINUX_FS_H */
    271