add f_flags to struct statfs(64)

Add a flags field to help glibc implementing statvfs(3) efficiently.

We copy the flag values from glibc, and add a new ST_VALID flag to
denote that f_flags is implemented.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Christoph Hellwig
2010-07-07 18:53:25 +02:00
committed by Al Viro
parent ebabe9a900
commit 365b181897
5 changed files with 89 additions and 13 deletions

View File

@@ -2,11 +2,49 @@
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/statfs.h>
#include <linux/security.h>
#include <linux/uaccess.h>
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);
}
int statfs_by_dentry(struct dentry *dentry, struct kstatfs *buf)
{
int retval;
@@ -26,7 +64,12 @@ int statfs_by_dentry(struct dentry *dentry, struct kstatfs *buf)
int vfs_statfs(struct path *path, struct kstatfs *buf)
{
return statfs_by_dentry(path->dentry, buf);
int error;
error = statfs_by_dentry(path->dentry, buf);
if (!error)
buf->f_flags = calculate_f_flags(path->mnt);
return error;
}
EXPORT_SYMBOL(vfs_statfs);
@@ -69,6 +112,7 @@ static int do_statfs_native(struct path *path, struct statfs *buf)
buf->f_fsid = st.f_fsid;
buf->f_namelen = st.f_namelen;
buf->f_frsize = st.f_frsize;
buf->f_flags = st.f_flags;
memset(buf->f_spare, 0, sizeof(buf->f_spare));
}
return 0;
@@ -96,6 +140,7 @@ static int do_statfs64(struct path *path, struct statfs64 *buf)
buf->f_fsid = st.f_fsid;
buf->f_namelen = st.f_namelen;
buf->f_frsize = st.f_frsize;
buf->f_flags = st.f_flags;
memset(buf->f_spare, 0, sizeof(buf->f_spare));
}
return 0;