pass a struct path to vfs_statfs

We'll need the path to implement the flags field for statvfs support.
We do have it available in all callers except:

 - ecryptfs_statfs.  This one doesn't actually need vfs_statfs but just
   needs to do a caller to the lower filesystem statfs method.
 - sys_ustat.  Add a non-exported statfs_by_dentry helper for it which
   doesn't won't be able to fill out the flags field later on.

In addition rename the helpers for statfs vs fstatfs to do_*statfs instead
of the misleading vfs prefix.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2 files changed, 13 insertions, 3 deletions

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index ac17a70..4d6154f 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -1756,6 +1756,10 @@ nfsd4_encode_fattr(struct svc_fh *fhp, struct svc_export *exp,
 	struct nfs4_acl *acl = NULL;
 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
 	u32 minorversion = resp->cstate.minorversion;
+	struct path path = {
+		.mnt	= exp->ex_path.mnt,
+		.dentry	= dentry,
+	};
 
 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
 	BUG_ON(bmval0 & ~nfsd_suppattrs0(minorversion));
@@ -1776,7 +1780,7 @@ nfsd4_encode_fattr(struct svc_fh *fhp, struct svc_export *exp,
 			FATTR4_WORD0_MAXNAME)) ||
 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
 		       FATTR4_WORD1_SPACE_TOTAL))) {
-		err = vfs_statfs(dentry, &statfs);
+		err = vfs_statfs(&path, &statfs);
 		if (err)
 			goto out_nfserr;
 	}
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 3c11112..f6f1a71 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -2019,8 +2019,14 @@ out:
 __be32
 nfsd_statfs(struct svc_rqst *rqstp, struct svc_fh *fhp, struct kstatfs *stat, int access)
 {
-	__be32 err = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP | access);
-	if (!err && vfs_statfs(fhp->fh_dentry,stat))
+	struct path path = {
+		.mnt	= fhp->fh_export->ex_path.mnt,
+		.dentry	= fhp->fh_dentry,
+	};
+	__be32 err;
+
+	err = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP | access);
+	if (!err && vfs_statfs(&path, stat))
 		err = nfserr_io;
 	return err;
 }