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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 00000000000..4ef021f3b61
--- /dev/null
+++ b/fs/statfs.c
@@ -0,0 +1,196 @@
+#include <linux/syscalls.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/namei.h>
+#include <linux/statfs.h>
+#include <linux/security.h>
+#include <linux/uaccess.h>
+
+int vfs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+ int retval = -ENODEV;
+
+ if (dentry) {
+ retval = -ENOSYS;
+ if (dentry->d_sb->s_op->statfs) {
+ 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;
+ }
+ }
+ return retval;
+}
+
+EXPORT_SYMBOL(vfs_statfs);
+
+static int vfs_statfs_native(struct dentry *dentry, struct statfs *buf)
+{
+ struct kstatfs st;
+ int retval;
+
+ retval = vfs_statfs(dentry, &st);
+ 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;
+ memset(buf->f_spare, 0, sizeof(buf->f_spare));
+ }
+ return 0;
+}
+
+static int vfs_statfs64(struct dentry *dentry, struct statfs64 *buf)
+{
+ struct kstatfs st;
+ int retval;
+
+ retval = vfs_statfs(dentry, &st);
+ 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;
+ 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;
+ error = vfs_statfs_native(path.dentry, &tmp);
+ 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;
+ error = vfs_statfs64(path.dentry, &tmp);
+ 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;
+ error = vfs_statfs_native(file->f_path.dentry, &tmp);
+ 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;
+ error = vfs_statfs64(file->f_path.dentry, &tmp);
+ 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;
+
+ err = vfs_statfs(s->s_root, &sbuf);
+ 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;
+}