1 #include <linux/syscalls.h>
2 #include <linux/module.h>
4 #include <linux/file.h>
5 #include <linux/mount.h>
6 #include <linux/namei.h>
7 #include <linux/statfs.h>
8 #include <linux/security.h>
9 #include <linux/uaccess.h>
11 static int flags_by_mnt(int mnt_flags)
15 if (mnt_flags & MNT_READONLY)
17 if (mnt_flags & MNT_NOSUID)
19 if (mnt_flags & MNT_NODEV)
21 if (mnt_flags & MNT_NOEXEC)
23 if (mnt_flags & MNT_NOATIME)
25 if (mnt_flags & MNT_NODIRATIME)
26 flags |= ST_NODIRATIME;
27 if (mnt_flags & MNT_RELATIME)
32 static int flags_by_sb(int s_flags)
35 if (s_flags & MS_SYNCHRONOUS)
36 flags |= ST_SYNCHRONOUS;
37 if (s_flags & MS_MANDLOCK)
42 static int calculate_f_flags(struct vfsmount *mnt)
44 return ST_VALID | flags_by_mnt(mnt->mnt_flags) |
45 flags_by_sb(mnt->mnt_sb->s_flags);
48 int statfs_by_dentry(struct dentry *dentry, struct kstatfs *buf)
52 if (!dentry->d_sb->s_op->statfs)
55 memset(buf, 0, sizeof(*buf));
56 retval = security_sb_statfs(dentry);
59 retval = dentry->d_sb->s_op->statfs(dentry, buf);
60 if (retval == 0 && buf->f_frsize == 0)
61 buf->f_frsize = buf->f_bsize;
65 int vfs_statfs(struct path *path, struct kstatfs *buf)
69 error = statfs_by_dentry(path->dentry, buf);
71 buf->f_flags = calculate_f_flags(path->mnt);
74 EXPORT_SYMBOL(vfs_statfs);
76 int user_statfs(const char __user *pathname, struct kstatfs *st)
79 int error = user_path(pathname, &path);
81 error = vfs_statfs(&path, st);
87 int fd_statfs(int fd, struct kstatfs *st)
89 struct file *file = fget(fd);
92 error = vfs_statfs(&file->f_path, st);
98 static int do_statfs_native(struct kstatfs *st, struct statfs __user *p)
102 if (sizeof(buf) == sizeof(*st))
103 memcpy(&buf, st, sizeof(*st));
105 if (sizeof buf.f_blocks == 4) {
106 if ((st->f_blocks | st->f_bfree | st->f_bavail |
107 st->f_bsize | st->f_frsize) &
108 0xffffffff00000000ULL)
111 * f_files and f_ffree may be -1; it's okay to stuff
114 if (st->f_files != -1 &&
115 (st->f_files & 0xffffffff00000000ULL))
117 if (st->f_ffree != -1 &&
118 (st->f_ffree & 0xffffffff00000000ULL))
122 buf.f_type = st->f_type;
123 buf.f_bsize = st->f_bsize;
124 buf.f_blocks = st->f_blocks;
125 buf.f_bfree = st->f_bfree;
126 buf.f_bavail = st->f_bavail;
127 buf.f_files = st->f_files;
128 buf.f_ffree = st->f_ffree;
129 buf.f_fsid = st->f_fsid;
130 buf.f_namelen = st->f_namelen;
131 buf.f_frsize = st->f_frsize;
132 buf.f_flags = st->f_flags;
133 memset(buf.f_spare, 0, sizeof(buf.f_spare));
135 if (copy_to_user(p, &buf, sizeof(buf)))
140 static int do_statfs64(struct kstatfs *st, struct statfs64 __user *p)
143 if (sizeof(buf) == sizeof(*st))
144 memcpy(&buf, st, sizeof(*st));
146 buf.f_type = st->f_type;
147 buf.f_bsize = st->f_bsize;
148 buf.f_blocks = st->f_blocks;
149 buf.f_bfree = st->f_bfree;
150 buf.f_bavail = st->f_bavail;
151 buf.f_files = st->f_files;
152 buf.f_ffree = st->f_ffree;
153 buf.f_fsid = st->f_fsid;
154 buf.f_namelen = st->f_namelen;
155 buf.f_frsize = st->f_frsize;
156 buf.f_flags = st->f_flags;
157 memset(buf.f_spare, 0, sizeof(buf.f_spare));
159 if (copy_to_user(p, &buf, sizeof(buf)))
164 SYSCALL_DEFINE2(statfs, const char __user *, pathname, struct statfs __user *, buf)
167 int error = user_statfs(pathname, &st);
169 error = do_statfs_native(&st, buf);
173 SYSCALL_DEFINE3(statfs64, const char __user *, pathname, size_t, sz, struct statfs64 __user *, buf)
177 if (sz != sizeof(*buf))
179 error = user_statfs(pathname, &st);
181 error = do_statfs64(&st, buf);
185 SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct statfs __user *, buf)
188 int error = fd_statfs(fd, &st);
190 error = do_statfs_native(&st, buf);
194 SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, size_t, sz, struct statfs64 __user *, buf)
199 if (sz != sizeof(*buf))
202 error = fd_statfs(fd, &st);
204 error = do_statfs64(&st, buf);
208 SYSCALL_DEFINE2(ustat, unsigned, dev, struct ustat __user *, ubuf)
210 struct super_block *s;
215 s = user_get_super(new_decode_dev(dev));
219 err = statfs_by_dentry(s->s_root, &sbuf);
224 memset(&tmp,0,sizeof(struct ustat));
225 tmp.f_tfree = sbuf.f_bfree;
226 tmp.f_tinode = sbuf.f_ffree;
228 return copy_to_user(ubuf, &tmp, sizeof(struct ustat)) ? -EFAULT : 0;