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authorAl Viro <viro@zeniv.linux.org.uk>2010-03-23 10:37:36 -0400
committerAl Viro <viro@zeniv.linux.org.uk>2010-05-21 18:31:17 -0400
commit7ed1ee6118ae77330cae2a6d5e9383532f7dfb48 (patch)
tree5f91faf8ddb9b210f9f66b15bd5c82c04e9a54e9 /fs/statfs.c
parente8c26255992474a2161c63ce9d385827302e4530 (diff)
Take statfs variants to fs/statfs.c
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/statfs.c')
-rw-r--r--fs/statfs.c196
1 files changed, 196 insertions, 0 deletions
diff --git a/fs/statfs.c b/fs/statfs.c
new file mode 100644
index 000000000000..4ef021f3b612
--- /dev/null
+++ b/fs/statfs.c
@@ -0,0 +1,196 @@
1#include <linux/syscalls.h>
2#include <linux/module.h>
3#include <linux/fs.h>
4#include <linux/file.h>
5#include <linux/namei.h>
6#include <linux/statfs.h>
7#include <linux/security.h>
8#include <linux/uaccess.h>
9
10int vfs_statfs(struct dentry *dentry, struct kstatfs *buf)
11{
12 int retval = -ENODEV;
13
14 if (dentry) {
15 retval = -ENOSYS;
16 if (dentry->d_sb->s_op->statfs) {
17 memset(buf, 0, sizeof(*buf));
18 retval = security_sb_statfs(dentry);
19 if (retval)
20 return retval;
21 retval = dentry->d_sb->s_op->statfs(dentry, buf);
22 if (retval == 0 && buf->f_frsize == 0)
23 buf->f_frsize = buf->f_bsize;
24 }
25 }
26 return retval;
27}
28
29EXPORT_SYMBOL(vfs_statfs);
30
31static int vfs_statfs_native(struct dentry *dentry, struct statfs *buf)
32{
33 struct kstatfs st;
34 int retval;
35
36 retval = vfs_statfs(dentry, &st);
37 if (retval)
38 return retval;
39
40 if (sizeof(*buf) == sizeof(st))
41 memcpy(buf, &st, sizeof(st));
42 else {
43 if (sizeof buf->f_blocks == 4) {
44 if ((st.f_blocks | st.f_bfree | st.f_bavail |
45 st.f_bsize | st.f_frsize) &
46 0xffffffff00000000ULL)
47 return -EOVERFLOW;
48 /*
49 * f_files and f_ffree may be -1; it's okay to stuff
50 * that into 32 bits
51 */
52 if (st.f_files != -1 &&
53 (st.f_files & 0xffffffff00000000ULL))
54 return -EOVERFLOW;
55 if (st.f_ffree != -1 &&
56 (st.f_ffree & 0xffffffff00000000ULL))
57 return -EOVERFLOW;
58 }
59
60 buf->f_type = st.f_type;
61 buf->f_bsize = st.f_bsize;
62 buf->f_blocks = st.f_blocks;
63 buf->f_bfree = st.f_bfree;
64 buf->f_bavail = st.f_bavail;
65 buf->f_files = st.f_files;
66 buf->f_ffree = st.f_ffree;
67 buf->f_fsid = st.f_fsid;
68 buf->f_namelen = st.f_namelen;
69 buf->f_frsize = st.f_frsize;
70 memset(buf->f_spare, 0, sizeof(buf->f_spare));
71 }
72 return 0;
73}
74
75static int vfs_statfs64(struct dentry *dentry, struct statfs64 *buf)
76{
77 struct kstatfs st;
78 int retval;
79
80 retval = vfs_statfs(dentry, &st);
81 if (retval)
82 return retval;
83
84 if (sizeof(*buf) == sizeof(st))
85 memcpy(buf, &st, sizeof(st));
86 else {
87 buf->f_type = st.f_type;
88 buf->f_bsize = st.f_bsize;
89 buf->f_blocks = st.f_blocks;
90 buf->f_bfree = st.f_bfree;
91 buf->f_bavail = st.f_bavail;
92 buf->f_files = st.f_files;
93 buf->f_ffree = st.f_ffree;
94 buf->f_fsid = st.f_fsid;
95 buf->f_namelen = st.f_namelen;
96 buf->f_frsize = st.f_frsize;
97 memset(buf->f_spare, 0, sizeof(buf->f_spare));
98 }
99 return 0;
100}
101
102SYSCALL_DEFINE2(statfs, const char __user *, pathname, struct statfs __user *, buf)
103{
104 struct path path;
105 int error;
106
107 error = user_path(pathname, &path);
108 if (!error) {
109 struct statfs tmp;
110 error = vfs_statfs_native(path.dentry, &tmp);
111 if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
112 error = -EFAULT;
113 path_put(&path);
114 }
115 return error;
116}
117
118SYSCALL_DEFINE3(statfs64, const char __user *, pathname, size_t, sz, struct statfs64 __user *, buf)
119{
120 struct path path;
121 long error;
122
123 if (sz != sizeof(*buf))
124 return -EINVAL;
125 error = user_path(pathname, &path);
126 if (!error) {
127 struct statfs64 tmp;
128 error = vfs_statfs64(path.dentry, &tmp);
129 if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
130 error = -EFAULT;
131 path_put(&path);
132 }
133 return error;
134}
135
136SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct statfs __user *, buf)
137{
138 struct file *file;
139 struct statfs tmp;
140 int error;
141
142 error = -EBADF;
143 file = fget(fd);
144 if (!file)
145 goto out;
146 error = vfs_statfs_native(file->f_path.dentry, &tmp);
147 if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
148 error = -EFAULT;
149 fput(file);
150out:
151 return error;
152}
153
154SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, size_t, sz, struct statfs64 __user *, buf)
155{
156 struct file *file;
157 struct statfs64 tmp;
158 int error;
159
160 if (sz != sizeof(*buf))
161 return -EINVAL;
162
163 error = -EBADF;
164 file = fget(fd);
165 if (!file)
166 goto out;
167 error = vfs_statfs64(file->f_path.dentry, &tmp);
168 if (!error && copy_to_user(buf, &tmp, sizeof(tmp)))
169 error = -EFAULT;
170 fput(file);
171out:
172 return error;
173}
174
175SYSCALL_DEFINE2(ustat, unsigned, dev, struct ustat __user *, ubuf)
176{
177 struct super_block *s;
178 struct ustat tmp;
179 struct kstatfs sbuf;
180 int err;
181
182 s = user_get_super(new_decode_dev(dev));
183 if (!s)
184 return -EINVAL;
185
186 err = vfs_statfs(s->s_root, &sbuf);
187 drop_super(s);
188 if (err)
189 return err;
190
191 memset(&tmp,0,sizeof(struct ustat));
192 tmp.f_tfree = sbuf.f_bfree;
193 tmp.f_tinode = sbuf.f_ffree;
194
195 return copy_to_user(ubuf, &tmp, sizeof(struct ustat)) ? -EFAULT : 0;
196}