1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2#ifndef _LINUX_FS_H
3#define _LINUX_FS_H
4
5/*
6 * This file has definitions for some important file table structures
7 * and constants and structures used by various generic file system
8 * ioctl's. Please do not make any changes in this file before
9 * sending patches for review to linux-fsdevel@vger.kernel.org and
10 * linux-api@vger.kernel.org.
11 */
12
13#include <linux/limits.h>
14#include <linux/ioctl.h>
15#include <linux/types.h>
16#include <linux/fscrypt.h>
17
18/* Use of MS_* flags within the kernel is restricted to core mount(2) code. */
19#include <linux/mount.h>
20
21/*
22 * It's silly to have NR_OPEN bigger than NR_FILE, but you can change
23 * the file limit at runtime and only root can increase the per-process
24 * nr_file rlimit, so it's safe to set up a ridiculously high absolute
25 * upper limit on files-per-process.
26 *
27 * Some programs (notably those using select()) may have to be
28 * recompiled to take full advantage of the new limits..
29 */
30
31/* Fixed constants first: */
32#undef NR_OPEN
33#define INR_OPEN_CUR 1024 /* Initial setting for nfile rlimits */
34#define INR_OPEN_MAX 4096 /* Hard limit for nfile rlimits */
35
36#define BLOCK_SIZE_BITS 10
37#define BLOCK_SIZE (1<<BLOCK_SIZE_BITS)
38
39#define SEEK_SET 0 /* seek relative to beginning of file */
40#define SEEK_CUR 1 /* seek relative to current file position */
41#define SEEK_END 2 /* seek relative to end of file */
42#define SEEK_DATA 3 /* seek to the next data */
43#define SEEK_HOLE 4 /* seek to the next hole */
44#define SEEK_MAX SEEK_HOLE
45
46#define RENAME_NOREPLACE (1 << 0) /* Don't overwrite target */
47#define RENAME_EXCHANGE (1 << 1) /* Exchange source and dest */
48#define RENAME_WHITEOUT (1 << 2) /* Whiteout source */
49
50struct file_clone_range {
51 __s64 src_fd;
52 __u64 src_offset;
53 __u64 src_length;
54 __u64 dest_offset;
55};
56
57struct fstrim_range {
58 __u64 start;
59 __u64 len;
60 __u64 minlen;
61};
62
63/* extent-same (dedupe) ioctls; these MUST match the btrfs ioctl definitions */
64#define FILE_DEDUPE_RANGE_SAME 0
65#define FILE_DEDUPE_RANGE_DIFFERS 1
66
67/* from struct btrfs_ioctl_file_extent_same_info */
68struct file_dedupe_range_info {
69 __s64 dest_fd; /* in - destination file */
70 __u64 dest_offset; /* in - start of extent in destination */
71 __u64 bytes_deduped; /* out - total # of bytes we were able
72 * to dedupe from this file. */
73 /* status of this dedupe operation:
74 * < 0 for error
75 * == FILE_DEDUPE_RANGE_SAME if dedupe succeeds
76 * == FILE_DEDUPE_RANGE_DIFFERS if data differs
77 */
78 __s32 status; /* out - see above description */
79 __u32 reserved; /* must be zero */
80};
81
82/* from struct btrfs_ioctl_file_extent_same_args */
83struct file_dedupe_range {
84 __u64 src_offset; /* in - start of extent in source */
85 __u64 src_length; /* in - length of extent */
86 __u16 dest_count; /* in - total elements in info array */
87 __u16 reserved1; /* must be zero */
88 __u32 reserved2; /* must be zero */
89 struct file_dedupe_range_info info[0];
90};
91
92/* And dynamically-tunable limits and defaults: */
93struct files_stat_struct {
94 unsigned long nr_files; /* read only */
95 unsigned long nr_free_files; /* read only */
96 unsigned long max_files; /* tunable */
97};
98
99struct inodes_stat_t {
100 long nr_inodes;
101 long nr_unused;
102 long dummy[5]; /* padding for sysctl ABI compatibility */
103};
104
105
106#define NR_FILE 8192 /* this can well be larger on a larger system */
107
108/*
109 * Structure for FS_IOC_FSGETXATTR[A] and FS_IOC_FSSETXATTR.
110 */
111struct fsxattr {
112 __u32 fsx_xflags; /* xflags field value (get/set) */
113 __u32 fsx_extsize; /* extsize field value (get/set)*/
114 __u32 fsx_nextents; /* nextents field value (get) */
115 __u32 fsx_projid; /* project identifier (get/set) */
116 __u32 fsx_cowextsize; /* CoW extsize field value (get/set)*/
117 unsigned char fsx_pad[8];
118};
119
120/*
121 * Flags for the fsx_xflags field
122 */
123#define FS_XFLAG_REALTIME 0x00000001 /* data in realtime volume */
124#define FS_XFLAG_PREALLOC 0x00000002 /* preallocated file extents */
125#define FS_XFLAG_IMMUTABLE 0x00000008 /* file cannot be modified */
126#define FS_XFLAG_APPEND 0x00000010 /* all writes append */
127#define FS_XFLAG_SYNC 0x00000020 /* all writes synchronous */
128#define FS_XFLAG_NOATIME 0x00000040 /* do not update access time */
129#define FS_XFLAG_NODUMP 0x00000080 /* do not include in backups */
130#define FS_XFLAG_RTINHERIT 0x00000100 /* create with rt bit set */
131#define FS_XFLAG_PROJINHERIT 0x00000200 /* create with parents projid */
132#define FS_XFLAG_NOSYMLINKS 0x00000400 /* disallow symlink creation */
133#define FS_XFLAG_EXTSIZE 0x00000800 /* extent size allocator hint */
134#define FS_XFLAG_EXTSZINHERIT 0x00001000 /* inherit inode extent size */
135#define FS_XFLAG_NODEFRAG 0x00002000 /* do not defragment */
136#define FS_XFLAG_FILESTREAM 0x00004000 /* use filestream allocator */
137#define FS_XFLAG_DAX 0x00008000 /* use DAX for IO */
138#define FS_XFLAG_COWEXTSIZE 0x00010000 /* CoW extent size allocator hint */
139#define FS_XFLAG_HASATTR 0x80000000 /* no DIFLAG for this */
140
141/* the read-only stuff doesn't really belong here, but any other place is
142 probably as bad and I don't want to create yet another include file. */
143
144#define BLKROSET _IO(0x12,93) /* set device read-only (0 = read-write) */
145#define BLKROGET _IO(0x12,94) /* get read-only status (0 = read_write) */
146#define BLKRRPART _IO(0x12,95) /* re-read partition table */
147#define BLKGETSIZE _IO(0x12,96) /* return device size /512 (long *arg) */
148#define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */
149#define BLKRASET _IO(0x12,98) /* set read ahead for block device */
150#define BLKRAGET _IO(0x12,99) /* get current read ahead setting */
151#define BLKFRASET _IO(0x12,100)/* set filesystem (mm/filemap.c) read-ahead */
152#define BLKFRAGET _IO(0x12,101)/* get filesystem (mm/filemap.c) read-ahead */
153#define BLKSECTSET _IO(0x12,102)/* set max sectors per request (ll_rw_blk.c) */
154#define BLKSECTGET _IO(0x12,103)/* get max sectors per request (ll_rw_blk.c) */
155#define BLKSSZGET _IO(0x12,104)/* get block device sector size */
156#if 0
157#define BLKPG _IO(0x12,105)/* See blkpg.h */
158
159/* Some people are morons. Do not use sizeof! */
160
161#define BLKELVGET _IOR(0x12,106,size_t)/* elevator get */
162#define BLKELVSET _IOW(0x12,107,size_t)/* elevator set */
163/* This was here just to show that the number is taken -
164 probably all these _IO(0x12,*) ioctls should be moved to blkpg.h. */
165#endif
166/* A jump here: 108-111 have been used for various private purposes. */
167#define BLKBSZGET _IOR(0x12,112,size_t)
168#define BLKBSZSET _IOW(0x12,113,size_t)
169#define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */
170#define BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup)
171#define BLKTRACESTART _IO(0x12,116)
172#define BLKTRACESTOP _IO(0x12,117)
173#define BLKTRACETEARDOWN _IO(0x12,118)
174#define BLKDISCARD _IO(0x12,119)
175#define BLKIOMIN _IO(0x12,120)
176#define BLKIOOPT _IO(0x12,121)
177#define BLKALIGNOFF _IO(0x12,122)
178#define BLKPBSZGET _IO(0x12,123)
179#define BLKDISCARDZEROES _IO(0x12,124)
180#define BLKSECDISCARD _IO(0x12,125)
181#define BLKROTATIONAL _IO(0x12,126)
182#define BLKZEROOUT _IO(0x12,127)
183#define BLKGETDISKSEQ _IOR(0x12,128,__u64)
184/*
185 * A jump here: 130-136 are reserved for zoned block devices
186 * (see uapi/linux/blkzoned.h)
187 */
188
189#define BMAP_IOCTL 1 /* obsolete - kept for compatibility */
190#define FIBMAP _IO(0x00,1) /* bmap access */
191#define FIGETBSZ _IO(0x00,2) /* get the block size used for bmap */
192#define FIFREEZE _IOWR('X', 119, int) /* Freeze */
193#define FITHAW _IOWR('X', 120, int) /* Thaw */
194#define FITRIM _IOWR('X', 121, struct fstrim_range) /* Trim */
195#define FICLONE _IOW(0x94, 9, int)
196#define FICLONERANGE _IOW(0x94, 13, struct file_clone_range)
197#define FIDEDUPERANGE _IOWR(0x94, 54, struct file_dedupe_range)
198
199#define FSLABEL_MAX 256 /* Max chars for the interface; each fs may differ */
200
201#define FS_IOC_GETFLAGS _IOR('f', 1, long)
202#define FS_IOC_SETFLAGS _IOW('f', 2, long)
203#define FS_IOC_GETVERSION _IOR('v', 1, long)
204#define FS_IOC_SETVERSION _IOW('v', 2, long)
205#define FS_IOC_FIEMAP _IOWR('f', 11, struct fiemap)
206#define FS_IOC32_GETFLAGS _IOR('f', 1, int)
207#define FS_IOC32_SETFLAGS _IOW('f', 2, int)
208#define FS_IOC32_GETVERSION _IOR('v', 1, int)
209#define FS_IOC32_SETVERSION _IOW('v', 2, int)
210#define FS_IOC_FSGETXATTR _IOR('X', 31, struct fsxattr)
211#define FS_IOC_FSSETXATTR _IOW('X', 32, struct fsxattr)
212#define FS_IOC_GETFSLABEL _IOR(0x94, 49, char[FSLABEL_MAX])
213#define FS_IOC_SETFSLABEL _IOW(0x94, 50, char[FSLABEL_MAX])
214
215/*
216 * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)
217 *
218 * Note: for historical reasons, these flags were originally used and
219 * defined for use by ext2/ext3, and then other file systems started
220 * using these flags so they wouldn't need to write their own version
221 * of chattr/lsattr (which was shipped as part of e2fsprogs). You
222 * should think twice before trying to use these flags in new
223 * contexts, or trying to assign these flags, since they are used both
224 * as the UAPI and the on-disk encoding for ext2/3/4. Also, we are
225 * almost out of 32-bit flags. :-)
226 *
227 * We have recently hoisted FS_IOC_FSGETXATTR / FS_IOC_FSSETXATTR from
228 * XFS to the generic FS level interface. This uses a structure that
229 * has padding and hence has more room to grow, so it may be more
230 * appropriate for many new use cases.
231 *
232 * Please do not change these flags or interfaces before checking with
233 * linux-fsdevel@vger.kernel.org and linux-api@vger.kernel.org.
234 */
235#define FS_SECRM_FL 0x00000001 /* Secure deletion */
236#define FS_UNRM_FL 0x00000002 /* Undelete */
237#define FS_COMPR_FL 0x00000004 /* Compress file */
238#define FS_SYNC_FL 0x00000008 /* Synchronous updates */
239#define FS_IMMUTABLE_FL 0x00000010 /* Immutable file */
240#define FS_APPEND_FL 0x00000020 /* writes to file may only append */
241#define FS_NODUMP_FL 0x00000040 /* do not dump file */
242#define FS_NOATIME_FL 0x00000080 /* do not update atime */
243/* Reserved for compression usage... */
244#define FS_DIRTY_FL 0x00000100
245#define FS_COMPRBLK_FL 0x00000200 /* One or more compressed clusters */
246#define FS_NOCOMP_FL 0x00000400 /* Don't compress */
247/* End compression flags --- maybe not all used */
248#define FS_ENCRYPT_FL 0x00000800 /* Encrypted file */
249#define FS_BTREE_FL 0x00001000 /* btree format dir */
250#define FS_INDEX_FL 0x00001000 /* hash-indexed directory */
251#define FS_IMAGIC_FL 0x00002000 /* AFS directory */
252#define FS_JOURNAL_DATA_FL 0x00004000 /* Reserved for ext3 */
253#define FS_NOTAIL_FL 0x00008000 /* file tail should not be merged */
254#define FS_DIRSYNC_FL 0x00010000 /* dirsync behaviour (directories only) */
255#define FS_TOPDIR_FL 0x00020000 /* Top of directory hierarchies*/
256#define FS_HUGE_FILE_FL 0x00040000 /* Reserved for ext4 */
257#define FS_EXTENT_FL 0x00080000 /* Extents */
258#define FS_VERITY_FL 0x00100000 /* Verity protected inode */
259#define FS_EA_INODE_FL 0x00200000 /* Inode used for large EA */
260#define FS_EOFBLOCKS_FL 0x00400000 /* Reserved for ext4 */
261#define FS_NOCOW_FL 0x00800000 /* Do not cow file */
262#define FS_DAX_FL 0x02000000 /* Inode is DAX */
263#define FS_INLINE_DATA_FL 0x10000000 /* Reserved for ext4 */
264#define FS_PROJINHERIT_FL 0x20000000 /* Create with parents projid */
265#define FS_CASEFOLD_FL 0x40000000 /* Folder is case insensitive */
266#define FS_RESERVED_FL 0x80000000 /* reserved for ext2 lib */
267
268#define FS_FL_USER_VISIBLE 0x0003DFFF /* User visible flags */
269#define FS_FL_USER_MODIFIABLE 0x000380FF /* User modifiable flags */
270
271
272#define SYNC_FILE_RANGE_WAIT_BEFORE 1
273#define SYNC_FILE_RANGE_WRITE 2
274#define SYNC_FILE_RANGE_WAIT_AFTER 4
275#define SYNC_FILE_RANGE_WRITE_AND_WAIT (SYNC_FILE_RANGE_WRITE | \
276 SYNC_FILE_RANGE_WAIT_BEFORE | \
277 SYNC_FILE_RANGE_WAIT_AFTER)
278
279/*
280 * Flags for preadv2/pwritev2:
281 */
282
283typedef int __bitwise __kernel_rwf_t;
284
285/* high priority request, poll if possible */
286#define RWF_HIPRI ((__kernel_rwf_t)0x00000001)
287
288/* per-IO O_DSYNC */
289#define RWF_DSYNC ((__kernel_rwf_t)0x00000002)
290
291/* per-IO O_SYNC */
292#define RWF_SYNC ((__kernel_rwf_t)0x00000004)
293
294/* per-IO, return -EAGAIN if operation would block */
295#define RWF_NOWAIT ((__kernel_rwf_t)0x00000008)
296
297/* per-IO O_APPEND */
298#define RWF_APPEND ((__kernel_rwf_t)0x00000010)
299
300/* mask of flags supported by the kernel */
301#define RWF_SUPPORTED (RWF_HIPRI | RWF_DSYNC | RWF_SYNC | RWF_NOWAIT |\
302 RWF_APPEND)
303
304#endif /* _LINUX_FS_H */
305

source code of include/linux/fs.h