github.com/SagerNet/gvisor@v0.0.0-20210707092255-7731c139d75c/pkg/abi/linux/fs.go (about)

     1  // Copyright 2018 The gVisor Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package linux
    16  
    17  // Filesystem types used in statfs(2).
    18  //
    19  // See linux/magic.h.
    20  const (
    21  	ANON_INODE_FS_MAGIC   = 0x09041934
    22  	CGROUP_SUPER_MAGIC    = 0x27e0eb
    23  	DEVPTS_SUPER_MAGIC    = 0x00001cd1
    24  	EXT_SUPER_MAGIC       = 0xef53
    25  	FUSE_SUPER_MAGIC      = 0x65735546
    26  	OVERLAYFS_SUPER_MAGIC = 0x794c7630
    27  	PIPEFS_MAGIC          = 0x50495045
    28  	PROC_SUPER_MAGIC      = 0x9fa0
    29  	RAMFS_MAGIC           = 0x09041934
    30  	SOCKFS_MAGIC          = 0x534F434B
    31  	SYSFS_MAGIC           = 0x62656572
    32  	TMPFS_MAGIC           = 0x01021994
    33  	V9FS_MAGIC            = 0x01021997
    34  )
    35  
    36  // Filesystem path limits, from uapi/linux/limits.h.
    37  const (
    38  	NAME_MAX = 255
    39  	PATH_MAX = 4096
    40  )
    41  
    42  // Statfs is struct statfs, from uapi/asm-generic/statfs.h.
    43  //
    44  // +marshal
    45  type Statfs struct {
    46  	// Type is one of the filesystem magic values, defined above.
    47  	Type uint64
    48  
    49  	// BlockSize is the optimal transfer block size in bytes.
    50  	BlockSize int64
    51  
    52  	// Blocks is the maximum number of data blocks the filesystem may store, in
    53  	// units of BlockSize.
    54  	Blocks uint64
    55  
    56  	// BlocksFree is the number of free data blocks, in units of BlockSize.
    57  	BlocksFree uint64
    58  
    59  	// BlocksAvailable is the number of data blocks free for use by
    60  	// unprivileged users, in units of BlockSize.
    61  	BlocksAvailable uint64
    62  
    63  	// Files is the number of used file nodes on the filesystem.
    64  	Files uint64
    65  
    66  	// FileFress is the number of free file nodes on the filesystem.
    67  	FilesFree uint64
    68  
    69  	// FSID is the filesystem ID.
    70  	FSID [2]int32
    71  
    72  	// NameLength is the maximum file name length.
    73  	NameLength uint64
    74  
    75  	// FragmentSize is equivalent to BlockSize.
    76  	FragmentSize int64
    77  
    78  	// Flags is the set of filesystem mount flags.
    79  	Flags uint64
    80  
    81  	// Spare is unused.
    82  	Spare [4]uint64
    83  }
    84  
    85  // Whence argument to lseek(2), from include/uapi/linux/fs.h.
    86  const (
    87  	SEEK_SET  = 0
    88  	SEEK_CUR  = 1
    89  	SEEK_END  = 2
    90  	SEEK_DATA = 3
    91  	SEEK_HOLE = 4
    92  )
    93  
    94  // Sync_file_range flags, from include/uapi/linux/fs.h
    95  const (
    96  	SYNC_FILE_RANGE_WAIT_BEFORE = 1
    97  	SYNC_FILE_RANGE_WRITE       = 2
    98  	SYNC_FILE_RANGE_WAIT_AFTER  = 4
    99  )
   100  
   101  // Flag argument to renameat2(2), from include/uapi/linux/fs.h.
   102  const (
   103  	RENAME_NOREPLACE = (1 << 0) // Don't overwrite target.
   104  	RENAME_EXCHANGE  = (1 << 1) // Exchange src and dst.
   105  	RENAME_WHITEOUT  = (1 << 2) // Whiteout src.
   106  )