[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, 6 insertions, 6 deletions

diff --git a/arch/mips/kernel/sysirix.c b/arch/mips/kernel/sysirix.c
index 5407b784cd01..19e1ef43eb4b 100644
--- a/arch/mips/kernel/sysirix.c
+++ b/arch/mips/kernel/sysirix.c
@@ -694,7 +694,7 @@ asmlinkage int irix_statfs(const char __user *path,
         if (error)
                 goto out;
 
-        error = vfs_statfs(nd.dentry->d_inode->i_sb, &kbuf);
+        error = vfs_statfs(nd.dentry, &kbuf);
         if (error)
                 goto dput_and_out;
 
@@ -732,7 +732,7 @@ asmlinkage int irix_fstatfs(unsigned int fd, struct irix_statfs __user *buf)
                 goto out;
         }
 
-        error = vfs_statfs(file->f_dentry->d_inode->i_sb, &kbuf);
+        error = vfs_statfs(file->f_dentry, &kbuf);
         if (error)
                 goto out_f;
 
@@ -1360,7 +1360,7 @@ asmlinkage int irix_statvfs(char __user *fname, struct irix_statvfs __user *buf)
         error = user_path_walk(fname, &nd);
         if (error)
                 goto out;
-        error = vfs_statfs(nd.dentry->d_inode->i_sb, &kbuf);
+        error = vfs_statfs(nd.dentry, &kbuf);
         if (error)
                 goto dput_and_out;
 
@@ -1406,7 +1406,7 @@ asmlinkage int irix_fstatvfs(int fd, struct irix_statvfs __user *buf)
                 error = -EBADF;
                 goto out;
         }
-        error = vfs_statfs(file->f_dentry->d_inode->i_sb, &kbuf);
+        error = vfs_statfs(file->f_dentry, &kbuf);
         if (error)
                 goto out_f;
 
@@ -1611,7 +1611,7 @@ asmlinkage int irix_statvfs64(char __user *fname, struct irix_statvfs64 __user *
         error = user_path_walk(fname, &nd);
         if (error)
                 goto out;
-        error = vfs_statfs(nd.dentry->d_inode->i_sb, &kbuf);
+        error = vfs_statfs(nd.dentry, &kbuf);
         if (error)
                 goto dput_and_out;
 
@@ -1658,7 +1658,7 @@ asmlinkage int irix_fstatvfs64(int fd, struct irix_statvfs __user *buf)
                 error = -EBADF;
                 goto out;
         }
-        error = vfs_statfs(file->f_dentry->d_inode->i_sb, &kbuf);
+        error = vfs_statfs(file->f_dentry, &kbuf);
         if (error)
                 goto out_f;