[PATCH] VFS: Permit filesystem to perform statfs with a known root dentry

Give the statfs superblock operation a dentry pointer rather than a superblock
pointer.

This complements the get_sb() patch.  That reduced the significance of
sb->s_root, allowing NFS to place a fake root there.  However, NFS does
require a dentry to use as a target for the statfs operation.  This permits
the root in the vfsmount to be used instead.

linux/mount.h has been added where necessary to make allyesconfig build
successfully.

Interest has also been expressed for use with the FUSE and XFS filesystems.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: Nathan Scott <nathans@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/arch/sparc64/solaris/fs.c b/arch/sparc64/solaris/fs.c
index 4885ca6cbc77..0f0eb6aa1c40 100644
--- a/arch/sparc64/solaris/fs.c
+++ b/arch/sparc64/solaris/fs.c
@@ -356,7 +356,7 @@ static int report_statvfs(struct vfsmount *mnt, struct inode *inode, u32 buf)
         int error;
         struct sol_statvfs __user *ss = A(buf);
 
-        error = vfs_statfs(mnt->mnt_sb, &s);
+        error = vfs_statfs(mnt->mnt_root, &s);
         if (!error) {
                 const char *p = mnt->mnt_sb->s_type->name;
                 int i = 0;
@@ -392,7 +392,7 @@ static int report_statvfs64(struct vfsmount *mnt, struct inode *inode, u32 buf)
         int error;
         struct sol_statvfs64 __user *ss = A(buf);
                         
-        error = vfs_statfs(mnt->mnt_sb, &s);
+        error = vfs_statfs(mnt->mnt_root, &s);
         if (!error) {
                 const char *p = mnt->mnt_sb->s_type->name;
                 int i = 0;