fs.h

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#ifndef _UAPI_LINUX_FS_H
#define _UAPI_LINUX_FS_H

/*
 * This file has definitions for some important file table
 * structures etc.
 */

#include <linux/limits.h>
#include <linux/ioctl.h>
#include <linux/types.h>

/*
 * It's silly to have NR_OPEN bigger than NR_FILE, but you can change
 * the file limit at runtime and only root can increase the per-process
 * nr_file rlimit, so it's safe to set up a ridiculously high absolute
 * upper limit on files-per-process.
 *
 * Some programs (notably those using select()) may have to be 
 * recompiled to take full advantage of the new limits..  
 */

/* Fixed constants first: */
#undef NR_OPEN
#define INR_OPEN_CUR 1024   /* Initial setting for nfile rlimits */
#define INR_OPEN_MAX 4096   /* Hard limit for nfile rlimits */

#define BLOCK_SIZE_BITS 10
#define BLOCK_SIZE (1<<BLOCK_SIZE_BITS)

#define SEEK_SET    0   /* seek relative to beginning of file */
#define SEEK_CUR    1   /* seek relative to current file position */
#define SEEK_END    2   /* seek relative to end of file */
#define SEEK_DATA   3   /* seek to the next data */
#define SEEK_HOLE   4   /* seek to the next hole */
#define SEEK_MAX    SEEK_HOLE

struct fstrim_range {
    __u64 start;
    __u64 len;
    __u64 minlen;
};

/* And dynamically-tunable limits and defaults: */
struct files_stat_struct {
    unsigned long nr_files;     /* read only */
    unsigned long nr_free_files;    /* read only */
    unsigned long max_files;        /* tunable */
};

struct inodes_stat_t {
    int nr_inodes;
    int nr_unused;
    int dummy[5];       /* padding for sysctl ABI compatibility */
};


#define NR_FILE  8192   /* this can well be larger on a larger system */


/*
 * These are the fs-independent mount-flags: up to 32 flags are supported
 */
#define MS_RDONLY    1  /* Mount read-only */
#define MS_NOSUID    2  /* Ignore suid and sgid bits */
#define MS_NODEV     4  /* Disallow access to device special files */
#define MS_NOEXEC    8  /* Disallow program execution */
#define MS_SYNCHRONOUS  16  /* Writes are synced at once */
#define MS_REMOUNT  32  /* Alter flags of a mounted FS */
#define MS_MANDLOCK 64  /* Allow mandatory locks on an FS */
#define MS_DIRSYNC  128 /* Directory modifications are synchronous */
#define MS_NOATIME  1024    /* Do not update access times. */
#define MS_NODIRATIME   2048    /* Do not update directory access times */
#define MS_BIND     4096
#define MS_MOVE     8192
#define MS_REC      16384
#define MS_VERBOSE  32768   /* War is peace. Verbosity is silence.
                   MS_VERBOSE is deprecated. */
#define MS_SILENT   32768
#define MS_POSIXACL (1<<16) /* VFS does not apply the umask */
#define MS_UNBINDABLE   (1<<17) /* change to unbindable */
#define MS_PRIVATE  (1<<18) /* change to private */
#define MS_SLAVE    (1<<19) /* change to slave */
#define MS_SHARED   (1<<20) /* change to shared */
#define MS_RELATIME (1<<21) /* Update atime relative to mtime/ctime. */
#define MS_KERNMOUNT    (1<<22) /* this is a kern_mount call */
#define MS_I_VERSION    (1<<23) /* Update inode I_version field */
#define MS_STRICTATIME  (1<<24) /* Always perform atime updates */
#define MS_NOSEC    (1<<28)
#define MS_BORN     (1<<29)
#define MS_ACTIVE   (1<<30)
#define MS_NOUSER   (1<<31)

/*
 * Superblock flags that can be altered by MS_REMOUNT
 */
#define MS_RMT_MASK (MS_RDONLY|MS_SYNCHRONOUS|MS_MANDLOCK|MS_I_VERSION)

/*
 * Old magic mount flag and mask
 */
#define MS_MGC_VAL 0xC0ED0000
#define MS_MGC_MSK 0xffff0000

/* the read-only stuff doesn't really belong here, but any other place is
   probably as bad and I don't want to create yet another include file. */

#define BLKROSET   _IO(0x12,93) /* set device read-only (0 = read-write) */
#define BLKROGET   _IO(0x12,94) /* get read-only status (0 = read_write) */
#define BLKRRPART  _IO(0x12,95) /* re-read partition table */
#define BLKGETSIZE _IO(0x12,96) /* return device size /512 (long *arg) */
#define BLKFLSBUF  _IO(0x12,97) /* flush buffer cache */
#define BLKRASET   _IO(0x12,98) /* set read ahead for block device */
#define BLKRAGET   _IO(0x12,99) /* get current read ahead setting */
#define BLKFRASET  _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
#define BLKFRAGET  _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
#define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
#define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
#define BLKSSZGET  _IO(0x12,104)/* get block device sector size */
#if 0
#define BLKPG      _IO(0x12,105)/* See blkpg.h */

/* Some people are morons.  Do not use sizeof! */

#define BLKELVGET  _IOR(0x12,106,size_t)/* elevator get */
#define BLKELVSET  _IOW(0x12,107,size_t)/* elevator set */
/* This was here just to show that the number is taken -
   probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */
#endif
/* A jump here: 108-111 have been used for various private purposes. */
#define BLKBSZGET  _IOR(0x12,112,size_t)
#define BLKBSZSET  _IOW(0x12,113,size_t)
#define BLKGETSIZE64 _IOR(0x12,114,size_t)  /* return device size in bytes (u64 *arg) */
#define BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup)
#define BLKTRACESTART _IO(0x12,116)
#define BLKTRACESTOP _IO(0x12,117)
#define BLKTRACETEARDOWN _IO(0x12,118)
#define BLKDISCARD _IO(0x12,119)
#define BLKIOMIN _IO(0x12,120)
#define BLKIOOPT _IO(0x12,121)
#define BLKALIGNOFF _IO(0x12,122)
#define BLKPBSZGET _IO(0x12,123)
#define BLKDISCARDZEROES _IO(0x12,124)
#define BLKSECDISCARD _IO(0x12,125)
#define BLKROTATIONAL _IO(0x12,126)
#define BLKZEROOUT _IO(0x12,127)

#define BMAP_IOCTL 1        /* obsolete - kept for compatibility */
#define FIBMAP     _IO(0x00,1)  /* bmap access */
#define FIGETBSZ   _IO(0x00,2)  /* get the block size used for bmap */
#define FIFREEZE    _IOWR('X', 119, int)    /* Freeze */
#define FITHAW      _IOWR('X', 120, int)    /* Thaw */
#define FITRIM      _IOWR('X', 121, struct fstrim_range)    /* Trim */

#define FS_IOC_GETFLAGS         _IOR('f', 1, long)
#define FS_IOC_SETFLAGS         _IOW('f', 2, long)
#define FS_IOC_GETVERSION       _IOR('v', 1, long)
#define FS_IOC_SETVERSION       _IOW('v', 2, long)
#define FS_IOC_FIEMAP           _IOWR('f', 11, struct fiemap)
#define FS_IOC32_GETFLAGS       _IOR('f', 1, int)
#define FS_IOC32_SETFLAGS       _IOW('f', 2, int)
#define FS_IOC32_GETVERSION     _IOR('v', 1, int)
#define FS_IOC32_SETVERSION     _IOW('v', 2, int)

/*
 * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)
 */
#define FS_SECRM_FL         0x00000001 /* Secure deletion */
#define FS_UNRM_FL          0x00000002 /* Undelete */
#define FS_COMPR_FL         0x00000004 /* Compress file */
#define FS_SYNC_FL          0x00000008 /* Synchronous updates */
#define FS_IMMUTABLE_FL         0x00000010 /* Immutable file */
#define FS_APPEND_FL            0x00000020 /* writes to file may only append */
#define FS_NODUMP_FL            0x00000040 /* do not dump file */
#define FS_NOATIME_FL           0x00000080 /* do not update atime */
/* Reserved for compression usage... */
#define FS_DIRTY_FL         0x00000100
#define FS_COMPRBLK_FL          0x00000200 /* One or more compressed clusters */
#define FS_NOCOMP_FL            0x00000400 /* Don't compress */
#define FS_ECOMPR_FL            0x00000800 /* Compression error */
/* End compression flags --- maybe not all used */
#define FS_BTREE_FL         0x00001000 /* btree format dir */
#define FS_INDEX_FL         0x00001000 /* hash-indexed directory */
#define FS_IMAGIC_FL            0x00002000 /* AFS directory */
#define FS_JOURNAL_DATA_FL      0x00004000 /* Reserved for ext3 */
#define FS_NOTAIL_FL            0x00008000 /* file tail should not be merged */
#define FS_DIRSYNC_FL           0x00010000 /* dirsync behaviour (directories only) */
#define FS_TOPDIR_FL            0x00020000 /* Top of directory hierarchies*/
#define FS_EXTENT_FL            0x00080000 /* Extents */
#define FS_DIRECTIO_FL          0x00100000 /* Use direct i/o */
#define FS_NOCOW_FL         0x00800000 /* Do not cow file */
#define FS_RESERVED_FL          0x80000000 /* reserved for ext2 lib */

#define FS_FL_USER_VISIBLE      0x0003DFFF /* User visible flags */
#define FS_FL_USER_MODIFIABLE       0x000380FF /* User modifiable flags */


#define SYNC_FILE_RANGE_WAIT_BEFORE 1
#define SYNC_FILE_RANGE_WRITE       2
#define SYNC_FILE_RANGE_WAIT_AFTER  4

#endif /* _UAPI_LINUX_FS_H */