Blame view
fs/statfs.c
5.16 KB
7ed1ee611
|
1 2 3 4 |
#include <linux/syscalls.h> #include <linux/module.h> #include <linux/fs.h> #include <linux/file.h> |
365b18189
|
5 |
#include <linux/mount.h> |
7ed1ee611
|
6 7 8 9 |
#include <linux/namei.h> #include <linux/statfs.h> #include <linux/security.h> #include <linux/uaccess.h> |
365b18189
|
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 |
static int flags_by_mnt(int mnt_flags) { int flags = 0; if (mnt_flags & MNT_READONLY) flags |= ST_RDONLY; if (mnt_flags & MNT_NOSUID) flags |= ST_NOSUID; if (mnt_flags & MNT_NODEV) flags |= ST_NODEV; if (mnt_flags & MNT_NOEXEC) flags |= ST_NOEXEC; if (mnt_flags & MNT_NOATIME) flags |= ST_NOATIME; if (mnt_flags & MNT_NODIRATIME) flags |= ST_NODIRATIME; if (mnt_flags & MNT_RELATIME) flags |= ST_RELATIME; return flags; } static int flags_by_sb(int s_flags) { int flags = 0; if (s_flags & MS_SYNCHRONOUS) flags |= ST_SYNCHRONOUS; if (s_flags & MS_MANDLOCK) flags |= ST_MANDLOCK; return flags; } static int calculate_f_flags(struct vfsmount *mnt) { return ST_VALID | flags_by_mnt(mnt->mnt_flags) | flags_by_sb(mnt->mnt_sb->s_flags); } |
ebabe9a90
|
46 |
int statfs_by_dentry(struct dentry *dentry, struct kstatfs *buf) |
7ed1ee611
|
47 |
{ |
ebabe9a90
|
48 49 50 51 52 53 54 55 56 57 58 59 |
int retval; if (!dentry->d_sb->s_op->statfs) return -ENOSYS; memset(buf, 0, sizeof(*buf)); retval = security_sb_statfs(dentry); if (retval) return retval; retval = dentry->d_sb->s_op->statfs(dentry, buf); if (retval == 0 && buf->f_frsize == 0) buf->f_frsize = buf->f_bsize; |
7ed1ee611
|
60 61 |
return retval; } |
ebabe9a90
|
62 63 |
int vfs_statfs(struct path *path, struct kstatfs *buf) { |
365b18189
|
64 65 66 67 68 69 |
int error; error = statfs_by_dentry(path->dentry, buf); if (!error) buf->f_flags = calculate_f_flags(path->mnt); return error; |
ebabe9a90
|
70 |
} |
7ed1ee611
|
71 |
EXPORT_SYMBOL(vfs_statfs); |
ebabe9a90
|
72 |
static int do_statfs_native(struct path *path, struct statfs *buf) |
7ed1ee611
|
73 74 75 |
{ struct kstatfs st; int retval; |
ebabe9a90
|
76 |
retval = vfs_statfs(path, &st); |
7ed1ee611
|
77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 |
if (retval) return retval; if (sizeof(*buf) == sizeof(st)) memcpy(buf, &st, sizeof(st)); else { if (sizeof buf->f_blocks == 4) { if ((st.f_blocks | st.f_bfree | st.f_bavail | st.f_bsize | st.f_frsize) & 0xffffffff00000000ULL) return -EOVERFLOW; /* * f_files and f_ffree may be -1; it's okay to stuff * that into 32 bits */ if (st.f_files != -1 && (st.f_files & 0xffffffff00000000ULL)) return -EOVERFLOW; if (st.f_ffree != -1 && (st.f_ffree & 0xffffffff00000000ULL)) return -EOVERFLOW; } buf->f_type = st.f_type; buf->f_bsize = st.f_bsize; buf->f_blocks = st.f_blocks; buf->f_bfree = st.f_bfree; buf->f_bavail = st.f_bavail; buf->f_files = st.f_files; buf->f_ffree = st.f_ffree; buf->f_fsid = st.f_fsid; buf->f_namelen = st.f_namelen; buf->f_frsize = st.f_frsize; |
365b18189
|
110 |
buf->f_flags = st.f_flags; |
7ed1ee611
|
111 112 113 114 |
memset(buf->f_spare, 0, sizeof(buf->f_spare)); } return 0; } |
ebabe9a90
|
115 |
static int do_statfs64(struct path *path, struct statfs64 *buf) |
7ed1ee611
|
116 117 118 |
{ struct kstatfs st; int retval; |
ebabe9a90
|
119 |
retval = vfs_statfs(path, &st); |
7ed1ee611
|
120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 |
if (retval) return retval; if (sizeof(*buf) == sizeof(st)) memcpy(buf, &st, sizeof(st)); else { buf->f_type = st.f_type; buf->f_bsize = st.f_bsize; buf->f_blocks = st.f_blocks; buf->f_bfree = st.f_bfree; buf->f_bavail = st.f_bavail; buf->f_files = st.f_files; buf->f_ffree = st.f_ffree; buf->f_fsid = st.f_fsid; buf->f_namelen = st.f_namelen; buf->f_frsize = st.f_frsize; |
365b18189
|
136 |
buf->f_flags = st.f_flags; |
7ed1ee611
|
137 138 139 140 141 142 143 144 145 146 147 148 149 |
memset(buf->f_spare, 0, sizeof(buf->f_spare)); } return 0; } SYSCALL_DEFINE2(statfs, const char __user *, pathname, struct statfs __user *, buf) { struct path path; int error; error = user_path(pathname, &path); if (!error) { struct statfs tmp; |
ebabe9a90
|
150 |
error = do_statfs_native(&path, &tmp); |
7ed1ee611
|
151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 |
if (!error && copy_to_user(buf, &tmp, sizeof(tmp))) error = -EFAULT; path_put(&path); } return error; } SYSCALL_DEFINE3(statfs64, const char __user *, pathname, size_t, sz, struct statfs64 __user *, buf) { struct path path; long error; if (sz != sizeof(*buf)) return -EINVAL; error = user_path(pathname, &path); if (!error) { struct statfs64 tmp; |
ebabe9a90
|
168 |
error = do_statfs64(&path, &tmp); |
7ed1ee611
|
169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 |
if (!error && copy_to_user(buf, &tmp, sizeof(tmp))) error = -EFAULT; path_put(&path); } return error; } SYSCALL_DEFINE2(fstatfs, unsigned int, fd, struct statfs __user *, buf) { struct file *file; struct statfs tmp; int error; error = -EBADF; file = fget(fd); if (!file) goto out; |
ebabe9a90
|
186 |
error = do_statfs_native(&file->f_path, &tmp); |
7ed1ee611
|
187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 |
if (!error && copy_to_user(buf, &tmp, sizeof(tmp))) error = -EFAULT; fput(file); out: return error; } SYSCALL_DEFINE3(fstatfs64, unsigned int, fd, size_t, sz, struct statfs64 __user *, buf) { struct file *file; struct statfs64 tmp; int error; if (sz != sizeof(*buf)) return -EINVAL; error = -EBADF; file = fget(fd); if (!file) goto out; |
ebabe9a90
|
207 |
error = do_statfs64(&file->f_path, &tmp); |
7ed1ee611
|
208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 |
if (!error && copy_to_user(buf, &tmp, sizeof(tmp))) error = -EFAULT; fput(file); out: return error; } SYSCALL_DEFINE2(ustat, unsigned, dev, struct ustat __user *, ubuf) { struct super_block *s; struct ustat tmp; struct kstatfs sbuf; int err; s = user_get_super(new_decode_dev(dev)); if (!s) return -EINVAL; |
ebabe9a90
|
225 |
err = statfs_by_dentry(s->s_root, &sbuf); |
7ed1ee611
|
226 227 228 229 230 231 232 233 234 235 |
drop_super(s); if (err) return err; memset(&tmp,0,sizeof(struct ustat)); tmp.f_tfree = sbuf.f_bfree; tmp.f_tinode = sbuf.f_ffree; return copy_to_user(ubuf, &tmp, sizeof(struct ustat)) ? -EFAULT : 0; } |