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ocfs2: mark local functions as static
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82b0547c 1#include <linux/compiler.h>
1c710c89 2#include <linux/file.h>
82b0547c
AD
3#include <linux/fs.h>
4#include <linux/linkage.h>
74f9fdfa 5#include <linux/mount.h>
82b0547c 6#include <linux/namei.h>
914e2637 7#include <linux/sched.h>
1c710c89 8#include <linux/stat.h>
82b0547c 9#include <linux/utime.h>
12c2ab5e 10#include <linux/syscalls.h>
82b0547c
AD
11#include <asm/uaccess.h>
12#include <asm/unistd.h>
13
14#ifdef __ARCH_WANT_SYS_UTIME
15
16/*
17 * sys_utime() can be implemented in user-level using sys_utimes().
18 * Is this for backwards compatibility? If so, why not move it
19 * into the appropriate arch directory (for those architectures that
20 * need it).
21 */
22
23/* If times==NULL, set access and modification to current time,
24 * must be owner or have write permission.
25 * Else, update from *times, must be owner or super user.
26 */
003d7ab4 27SYSCALL_DEFINE2(utime, char __user *, filename, struct utimbuf __user *, times)
82b0547c 28{
1c710c89 29 struct timespec tv[2];
82b0547c 30
82b0547c 31 if (times) {
1c710c89
UD
32 if (get_user(tv[0].tv_sec, &times->actime) ||
33 get_user(tv[1].tv_sec, &times->modtime))
34 return -EFAULT;
35 tv[0].tv_nsec = 0;
36 tv[1].tv_nsec = 0;
82b0547c 37 }
1c710c89 38 return do_utimes(AT_FDCWD, filename, times ? tv : NULL, 0);
82b0547c
AD
39}
40
41#endif
42
043f46f6
MS
43static bool nsec_valid(long nsec)
44{
4cca9226 45 if (nsec == UTIME_OMIT || nsec == UTIME_NOW)
043f46f6
MS
46 return true;
47
48 return nsec >= 0 && nsec <= 999999999;
49}
50
e9b76fed 51static int utimes_common(struct path *path, struct timespec *times)
82b0547c
AD
52{
53 int error;
82b0547c 54 struct iattr newattrs;
e9b76fed 55 struct inode *inode = path->dentry->d_inode;
27ac0ffe 56 struct inode *delegated_inode = NULL;
82b0547c 57
e9b76fed 58 error = mnt_want_write(path->mnt);
74f9fdfa 59 if (error)
e9b76fed 60 goto out;
82b0547c 61
12fd0d30
MK
62 if (times && times[0].tv_nsec == UTIME_NOW &&
63 times[1].tv_nsec == UTIME_NOW)
64 times = NULL;
65
82b0547c
AD
66 newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME;
67 if (times) {
1c710c89
UD
68 if (times[0].tv_nsec == UTIME_OMIT)
69 newattrs.ia_valid &= ~ATTR_ATIME;
70 else if (times[0].tv_nsec != UTIME_NOW) {
71 newattrs.ia_atime.tv_sec = times[0].tv_sec;
72 newattrs.ia_atime.tv_nsec = times[0].tv_nsec;
73 newattrs.ia_valid |= ATTR_ATIME_SET;
74 }
75
76 if (times[1].tv_nsec == UTIME_OMIT)
77 newattrs.ia_valid &= ~ATTR_MTIME;
78 else if (times[1].tv_nsec != UTIME_NOW) {
79 newattrs.ia_mtime.tv_sec = times[1].tv_sec;
80 newattrs.ia_mtime.tv_nsec = times[1].tv_nsec;
81 newattrs.ia_valid |= ATTR_MTIME_SET;
82 }
4cca9226 83 /*
9767d749
MS
84 * Tell inode_change_ok(), that this is an explicit time
85 * update, even if neither ATTR_ATIME_SET nor ATTR_MTIME_SET
86 * were used.
4cca9226 87 */
9767d749 88 newattrs.ia_valid |= ATTR_TIMES_SET;
4cca9226 89 } else {
4cca9226
MK
90 /*
91 * If times is NULL (or both times are UTIME_NOW),
92 * then we need to check permissions, because
93 * inode_change_ok() won't do it.
94 */
82b0547c
AD
95 error = -EACCES;
96 if (IS_IMMUTABLE(inode))
74f9fdfa 97 goto mnt_drop_write_and_out;
82b0547c 98
2e149670 99 if (!inode_owner_or_capable(inode)) {
f419a2e3 100 error = inode_permission(inode, MAY_WRITE);
c70f8441
MK
101 if (error)
102 goto mnt_drop_write_and_out;
1e5de283 103 }
82b0547c 104 }
27ac0ffe 105retry_deleg:
82b0547c 106 mutex_lock(&inode->i_mutex);
27ac0ffe 107 error = notify_change(path->dentry, &newattrs, &delegated_inode);
82b0547c 108 mutex_unlock(&inode->i_mutex);
27ac0ffe
BF
109 if (delegated_inode) {
110 error = break_deleg_wait(&delegated_inode);
111 if (!error)
112 goto retry_deleg;
113 }
e9b76fed 114
74f9fdfa 115mnt_drop_write_and_out:
e9b76fed
MS
116 mnt_drop_write(path->mnt);
117out:
118 return error;
119}
120
121/*
122 * do_utimes - change times on filename or file descriptor
123 * @dfd: open file descriptor, -1 or AT_FDCWD
124 * @filename: path name or NULL
125 * @times: new times or NULL
126 * @flags: zero or more flags (only AT_SYMLINK_NOFOLLOW for the moment)
127 *
128 * If filename is NULL and dfd refers to an open file, then operate on
129 * the file. Otherwise look up filename, possibly using dfd as a
130 * starting point.
131 *
132 * If times==NULL, set access and modification to current time,
133 * must be owner or have write permission.
134 * Else, update from *times, must be owner or super user.
135 */
c7887325
DH
136long do_utimes(int dfd, const char __user *filename, struct timespec *times,
137 int flags)
e9b76fed
MS
138{
139 int error = -EINVAL;
140
141 if (times && (!nsec_valid(times[0].tv_nsec) ||
142 !nsec_valid(times[1].tv_nsec))) {
143 goto out;
144 }
145
146 if (flags & ~AT_SYMLINK_NOFOLLOW)
147 goto out;
148
149 if (filename == NULL && dfd != AT_FDCWD) {
2903ff01 150 struct fd f;
e9b76fed
MS
151
152 if (flags & AT_SYMLINK_NOFOLLOW)
153 goto out;
154
2903ff01 155 f = fdget(dfd);
e9b76fed 156 error = -EBADF;
2903ff01 157 if (!f.file)
e9b76fed
MS
158 goto out;
159
2903ff01
AV
160 error = utimes_common(&f.file->f_path, times);
161 fdput(f);
e9b76fed 162 } else {
2d8f3038 163 struct path path;
e9b76fed
MS
164 int lookup_flags = 0;
165
166 if (!(flags & AT_SYMLINK_NOFOLLOW))
167 lookup_flags |= LOOKUP_FOLLOW;
a69201d6 168retry:
2d8f3038 169 error = user_path_at(dfd, filename, lookup_flags, &path);
e9b76fed
MS
170 if (error)
171 goto out;
172
2d8f3038
AV
173 error = utimes_common(&path, times);
174 path_put(&path);
a69201d6
JL
175 if (retry_estale(error, lookup_flags)) {
176 lookup_flags |= LOOKUP_REVAL;
177 goto retry;
178 }
e9b76fed
MS
179 }
180
82b0547c
AD
181out:
182 return error;
183}
184
c7887325 185SYSCALL_DEFINE4(utimensat, int, dfd, const char __user *, filename,
6559eed8 186 struct timespec __user *, utimes, int, flags)
1c710c89
UD
187{
188 struct timespec tstimes[2];
189
190 if (utimes) {
191 if (copy_from_user(&tstimes, utimes, sizeof(tstimes)))
192 return -EFAULT;
1c710c89
UD
193
194 /* Nothing to do, we must not even check the path. */
195 if (tstimes[0].tv_nsec == UTIME_OMIT &&
196 tstimes[1].tv_nsec == UTIME_OMIT)
197 return 0;
198 }
199
200 return do_utimes(dfd, filename, utimes ? tstimes : NULL, flags);
201}
202
c7887325 203SYSCALL_DEFINE3(futimesat, int, dfd, const char __user *, filename,
6559eed8 204 struct timeval __user *, utimes)
82b0547c
AD
205{
206 struct timeval times[2];
1c710c89
UD
207 struct timespec tstimes[2];
208
209 if (utimes) {
210 if (copy_from_user(&times, utimes, sizeof(times)))
211 return -EFAULT;
212
213 /* This test is needed to catch all invalid values. If we
214 would test only in do_utimes we would miss those invalid
215 values truncated by the multiplication with 1000. Note
216 that we also catch UTIME_{NOW,OMIT} here which are only
217 valid for utimensat. */
218 if (times[0].tv_usec >= 1000000 || times[0].tv_usec < 0 ||
219 times[1].tv_usec >= 1000000 || times[1].tv_usec < 0)
220 return -EINVAL;
221
222 tstimes[0].tv_sec = times[0].tv_sec;
223 tstimes[0].tv_nsec = 1000 * times[0].tv_usec;
224 tstimes[1].tv_sec = times[1].tv_sec;
225 tstimes[1].tv_nsec = 1000 * times[1].tv_usec;
226 }
82b0547c 227
1c710c89 228 return do_utimes(dfd, filename, utimes ? tstimes : NULL, 0);
82b0547c
AD
229}
230
003d7ab4
HC
231SYSCALL_DEFINE2(utimes, char __user *, filename,
232 struct timeval __user *, utimes)
82b0547c
AD
233{
234 return sys_futimesat(AT_FDCWD, filename, utimes);
235}