NFS: Don't request readdirplus when revalidation was forced

If the revalidation was forced, due to the presence of a LOOKUP_EXCL or
a LOOKUP_REVAL flag, then readdirplus won't help. It also can't help
when we're doing a path component lookup.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index dcfc444..cf79746 100644 (file)
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -694,10 +694,13 @@ void nfs_readdir_record_entry_cache_miss(struct inode *dir)
        }
 }
 
-static void nfs_lookup_advise_force_readdirplus(struct inode *dir)
+static void nfs_lookup_advise_force_readdirplus(struct inode *dir,
+                                               unsigned int flags)
 {
        if (nfs_server_capable(dir, NFS_CAP_CASE_INSENSITIVE))
                return;
+       if (flags & (LOOKUP_EXCL | LOOKUP_PARENT | LOOKUP_REVAL))
+               return;
        nfs_readdir_record_entry_cache_miss(dir);
 }
 
@@ -1596,15 +1599,17 @@ nfs_lookup_revalidate_delegated(struct inode *dir, struct dentry *dentry,
        return nfs_lookup_revalidate_done(dir, dentry, inode, 1);
 }
 
-static int
-nfs_lookup_revalidate_dentry(struct inode *dir, struct dentry *dentry,
-                            struct inode *inode)
+static int nfs_lookup_revalidate_dentry(struct inode *dir,
+                                       struct dentry *dentry,
+                                       struct inode *inode, unsigned int flags)
 {
        struct nfs_fh *fhandle;
        struct nfs_fattr *fattr;
        unsigned long dir_verifier;
        int ret;
 
+       trace_nfs_lookup_revalidate_enter(dir, dentry, flags);
+
        ret = -ENOMEM;
        fhandle = nfs_alloc_fhandle();
        fattr = nfs_alloc_fattr_with_label(NFS_SERVER(inode));
@@ -1625,6 +1630,10 @@ nfs_lookup_revalidate_dentry(struct inode *dir, struct dentry *dentry,
                }
                goto out;
        }
+
+       /* Request help from readdirplus */
+       nfs_lookup_advise_force_readdirplus(dir, flags);
+
        ret = 0;
        if (nfs_compare_fh(NFS_FH(inode), fhandle))
                goto out;
@@ -1634,8 +1643,6 @@ nfs_lookup_revalidate_dentry(struct inode *dir, struct dentry *dentry,
        nfs_setsecurity(inode, fattr);
        nfs_set_verifier(dentry, dir_verifier);
 
-       /* set a readdirplus hint that we had a cache miss */
-       nfs_lookup_advise_force_readdirplus(dir);
        ret = 1;
 out:
        nfs_free_fattr(fattr);
@@ -1701,8 +1708,7 @@ nfs_do_lookup_revalidate(struct inode *dir, struct dentry *dentry,
        if (NFS_STALE(inode))
                goto out_bad;
 
-       trace_nfs_lookup_revalidate_enter(dir, dentry, flags);
-       return nfs_lookup_revalidate_dentry(dir, dentry, inode);
+       return nfs_lookup_revalidate_dentry(dir, dentry, inode, flags);
 out_valid:
        return nfs_lookup_revalidate_done(dir, dentry, inode, 1);
 out_bad:
@@ -1896,7 +1902,7 @@ struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, unsigned in
                goto out;
 
        /* Notify readdir to use READDIRPLUS */
-       nfs_lookup_advise_force_readdirplus(dir);
+       nfs_lookup_advise_force_readdirplus(dir, flags);
 
 no_entry:
        res = d_splice_alias(inode, dentry);
@@ -2159,7 +2165,7 @@ nfs4_do_lookup_revalidate(struct inode *dir, struct dentry *dentry,
 reval_dentry:
        if (flags & LOOKUP_RCU)
                return -ECHILD;
-       return nfs_lookup_revalidate_dentry(dir, dentry, inode);
+       return nfs_lookup_revalidate_dentry(dir, dentry, inode, flags);
 
 full_reval:
        return nfs_do_lookup_revalidate(dir, dentry, flags);