NFS: Use the dentry superblock directly in nfs_statfs()

Use the nominated dentry's superblock directly in the NFS statfs() op to get a
file handle, rather than using s_root (which will become a dummy dentry in a
future patch).

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 6 insertions, 7 deletions

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index f97d7d9c5c32..a41d516ed595 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -240,11 +240,10 @@ void __exit unregister_nfs_fs(void)
  */
 static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 {
-        struct super_block *sb = dentry->d_sb;
-        struct nfs_server *server = NFS_SB(sb);
+        struct nfs_server *server = NFS_SB(dentry->d_sb);
         unsigned char blockbits;
         unsigned long blockres;
-        struct nfs_fh *rootfh = NFS_FH(sb->s_root->d_inode);
+        struct nfs_fh *fh = NFS_FH(dentry->d_inode);
         struct nfs_fattr fattr;
         struct nfs_fsstat res = {
                         .fattr = &fattr,
@@ -253,7 +252,7 @@ static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 
         lock_kernel();
 
-        error = server->rpc_ops->statfs(server, rootfh, &res);
+        error = server->rpc_ops->statfs(server, fh, &res);
         buf->f_type = NFS_SUPER_MAGIC;
         if (error < 0)
                 goto out_err;
@@ -263,7 +262,7 @@ static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
          * case where f_frsize != f_bsize.  Eventually we want to
          * report the value of wtmult in this field.
          */
-        buf->f_frsize = sb->s_blocksize;
+        buf->f_frsize = dentry->d_sb->s_blocksize;
 
         /*
          * On most *nix systems, f_blocks, f_bfree, and f_bavail
@@ -272,8 +271,8 @@ static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
          * thus historically Linux's sys_statfs reports these
          * fields in units of f_bsize.
          */
-        buf->f_bsize = sb->s_blocksize;
-        blockbits = sb->s_blocksize_bits;
+        buf->f_bsize = dentry->d_sb->s_blocksize;
+        blockbits = dentry->d_sb->s_blocksize_bits;
         blockres = (1 << blockbits) - 1;
         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
         buf->f_bfree = (res.fbytes + blockres) >> blockbits;