NFS: Make nfs_fhget() return appropriate error values

Currently it returns NULL, which usually gets interpreted as ENOMEM. In
fact it can mean a host of issues.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

3 files changed, 13 insertions, 14 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 609185a15c99..06c48b385c94 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -901,9 +901,9 @@ static struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, stru
                 res = ERR_PTR(error);
                 goto out_unlock;
         }
-        res = ERR_PTR(-EACCES);
         inode = nfs_fhget(dentry->d_sb, &fhandle, &fattr);
-        if (!inode)
+        res = (struct dentry *)inode;
+        if (IS_ERR(res))
                 goto out_unlock;
 no_entry:
         res = d_add_unique(dentry, inode);
@@ -1096,7 +1096,7 @@ static struct dentry *nfs_readdir_lookup(nfs_readdir_descriptor_t *desc)
                 return NULL;
         dentry->d_op = NFS_PROTO(dir)->dentry_ops;
         inode = nfs_fhget(dentry->d_sb, entry->fh, entry->fattr);
-        if (!inode) {
+        if (IS_ERR(inode)) {
                 dput(dentry);
                 return NULL;
         }
@@ -1134,9 +1134,9 @@ int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fhandle,
                 if (error < 0)
                         goto out_err;
         }
-        error = -ENOMEM;
         inode = nfs_fhget(dentry->d_sb, fhandle, fattr);
-        if (inode == NULL)
+        error = PTR_ERR(inode);
+        if (IS_ERR(inode))
                 goto out_err;
         d_instantiate(dentry, inode);
         return 0;
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 17654bffc3c6..a0cda53461b3 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -241,7 +241,6 @@ static struct inode *
 nfs_get_root(struct super_block *sb, struct nfs_fh *rootfh, struct nfs_fsinfo *fsinfo)
 {
         struct nfs_server       *server = NFS_SB(sb);
-        struct inode *rooti;
         int                     error;
 
         error = server->rpc_ops->getroot(server, rootfh, fsinfo);
@@ -250,10 +249,7 @@ nfs_get_root(struct super_block *sb, struct nfs_fh *rootfh, struct nfs_fsinfo *f
                 return ERR_PTR(error);
         }
 
-        rooti = nfs_fhget(sb, rootfh, fsinfo->fattr);
-        if (!rooti)
-                return ERR_PTR(-ENOMEM);
-        return rooti;
+        return nfs_fhget(sb, rootfh, fsinfo->fattr);
 }
 
 /*
@@ -853,7 +849,7 @@ nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr)
                 .fh     = fh,
                 .fattr  = fattr
         };
-        struct inode *inode = NULL;
+        struct inode *inode = ERR_PTR(-ENOENT);
         unsigned long hash;
 
         if ((fattr->valid & NFS_ATTR_FATTR) == 0)
@@ -866,8 +862,11 @@ nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr)
 
         hash = nfs_fattr_to_ino_t(fattr);
 
-        if (!(inode = iget5_locked(sb, hash, nfs_find_actor, nfs_init_locked, &desc)))
+        inode = iget5_locked(sb, hash, nfs_find_actor, nfs_init_locked, &desc);
+        if (inode == NULL) {
+                inode = ERR_PTR(-ENOMEM);
                 goto out_no_inode;
+        }
 
         if (inode->i_state & I_NEW) {
                 struct nfs_inode *nfsi = NFS_I(inode);
@@ -936,7 +935,7 @@ out:
         return inode;
 
 out_no_inode:
-        printk("nfs_fhget: iget failed\n");
+        dprintk("nfs_fhget: iget failed with error %ld\n", PTR_ERR(inode));
         goto out;
 }
 
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 31000326aba4..02c7d8c04c58 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -336,7 +336,7 @@ static struct nfs4_state *nfs4_opendata_to_nfs4_state(struct nfs4_opendata *data
         if (!(data->f_attr.valid & NFS_ATTR_FATTR))
                 goto out;
         inode = nfs_fhget(data->dir->d_sb, &data->o_res.fh, &data->f_attr);
-        if (inode == NULL)
+        if (IS_ERR(inode))
                 goto out;
         state = nfs4_get_open_state(inode, data->owner);
         if (state == NULL)