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gerrit-public.fairphone.software / kernel / msm / bf591b24d07126143356058966d79423661f491f / . / fs / utimes.c
blob: 99cf2cb11fec4ad0090c9d2f12d966a7dadb1ef1 [file] [log] [blame]
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700[diff] [blame]1#include <linux/compiler.h>
2#include <linux/fs.h>
3#include <linux/linkage.h>
4#include <linux/namei.h>
Al Viro914e2632006-10-18 13:55:46 -0400[diff] [blame]5#include <linux/sched.h>
Alexey Dobriyan82b05472006-09-30 23:27:22 -0700[diff] [blame]6#include <linux/utime.h>
7#include <asm/uaccess.h>
8#include <asm/unistd.h>
9
10#ifdef __ARCH_WANT_SYS_UTIME
11
12/*
13 * sys_utime() can be implemented in user-level using sys_utimes().
14 * Is this for backwards compatibility? If so, why not move it
15 * into the appropriate arch directory (for those architectures that
16 * need it).
17 */
18
19/* If times==NULL, set access and modification to current time,
20 * must be owner or have write permission.
21 * Else, update from *times, must be owner or super user.
22 */
23asmlinkage long sys_utime(char __user * filename, struct utimbuf __user * times)
24{
25 int error;
26 struct nameidata nd;
27 struct inode * inode;
28 struct iattr newattrs;
29
30 error = user_path_walk(filename, &nd);
31 if (error)
32 goto out;
33 inode = nd.dentry->d_inode;
34
35 error = -EROFS;
36 if (IS_RDONLY(inode))
37 goto dput_and_out;
38
39 /* Don't worry, the checks are done in inode_change_ok() */
40 newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME;
41 if (times) {
42 error = -EPERM;
43 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
44 goto dput_and_out;
45
46 error = get_user(newattrs.ia_atime.tv_sec, &times->actime);
47 newattrs.ia_atime.tv_nsec = 0;
48 if (!error)
49 error = get_user(newattrs.ia_mtime.tv_sec, &times->modtime);
50 newattrs.ia_mtime.tv_nsec = 0;
51 if (error)
52 goto dput_and_out;
53
54 newattrs.ia_valid |= ATTR_ATIME_SET | ATTR_MTIME_SET;
55 } else {
56 error = -EACCES;
57 if (IS_IMMUTABLE(inode))
58 goto dput_and_out;
59
60 if (current->fsuid != inode->i_uid &&
61 (error = vfs_permission(&nd, MAY_WRITE)) != 0)
62 goto dput_and_out;
63 }
64 mutex_lock(&inode->i_mutex);
65 error = notify_change(nd.dentry, &newattrs);
66 mutex_unlock(&inode->i_mutex);
67dput_and_out:
68 path_release(&nd);
69out:
70 return error;
71}
72
73#endif
74
75/* If times==NULL, set access and modification to current time,
76 * must be owner or have write permission.
77 * Else, update from *times, must be owner or super user.
78 */
79long do_utimes(int dfd, char __user *filename, struct timeval *times)
80{
81 int error;
82 struct nameidata nd;
83 struct inode * inode;
84 struct iattr newattrs;
85
86 error = __user_walk_fd(dfd, filename, LOOKUP_FOLLOW, &nd);
87
88 if (error)
89 goto out;
90 inode = nd.dentry->d_inode;
91
92 error = -EROFS;
93 if (IS_RDONLY(inode))
94 goto dput_and_out;
95
96 /* Don't worry, the checks are done in inode_change_ok() */
97 newattrs.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_ATIME;
98 if (times) {
99 error = -EPERM;
100 if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
101 goto dput_and_out;
102
103 newattrs.ia_atime.tv_sec = times[0].tv_sec;
104 newattrs.ia_atime.tv_nsec = times[0].tv_usec * 1000;
105 newattrs.ia_mtime.tv_sec = times[1].tv_sec;
106 newattrs.ia_mtime.tv_nsec = times[1].tv_usec * 1000;
107 newattrs.ia_valid |= ATTR_ATIME_SET | ATTR_MTIME_SET;
108 } else {
109 error = -EACCES;
110 if (IS_IMMUTABLE(inode))
111 goto dput_and_out;
112
113 if (current->fsuid != inode->i_uid &&
114 (error = vfs_permission(&nd, MAY_WRITE)) != 0)
115 goto dput_and_out;
116 }
117 mutex_lock(&inode->i_mutex);
118 error = notify_change(nd.dentry, &newattrs);
119 mutex_unlock(&inode->i_mutex);
120dput_and_out:
121 path_release(&nd);
122out:
123 return error;
124}
125
126asmlinkage long sys_futimesat(int dfd, char __user *filename, struct timeval __user *utimes)
127{
128 struct timeval times[2];
129
130 if (utimes && copy_from_user(&times, utimes, sizeof(times)))
131 return -EFAULT;
132 return do_utimes(dfd, filename, utimes ? times : NULL);
133}
134
135asmlinkage long sys_utimes(char __user *filename, struct timeval __user *utimes)
136{
137 return sys_futimesat(AT_FDCWD, filename, utimes);
138}