nfs: clean up ->create in nfs_rpc_ops

Don't pass nfs_open_context() to ->create().  Only the NFS4 implementation
needed that and only because it wanted to return an open file using open
intents.  That task has been replaced by ->atomic_open so it is not necessary
anymore to pass the context to the create rpc operation.

Despite nfs4_proc_create apparently being okay with a NULL context it Oopses
somewhere down the call chain.  So allocate a context here.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

5 files changed, 15 insertions, 70 deletions

diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 0d8c71271d1a..45015d32a865 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -114,10 +114,8 @@ const struct inode_operations nfs3_dir_inode_operations = {
 static struct file *nfs_atomic_open(struct inode *, struct dentry *,
                                     struct opendata *, unsigned, umode_t,
                                     bool *);
-static int nfs4_create(struct inode *dir, struct dentry *dentry,
-                       umode_t mode, struct nameidata *nd);
 const struct inode_operations nfs4_dir_inode_operations = {
-        .create         = nfs4_create,
+        .create         = nfs_create,
         .lookup         = nfs_lookup,
         .atomic_open    = nfs_atomic_open,
         .link           = nfs_link,
@@ -1582,42 +1580,6 @@ no_open:
         return nfs_lookup_revalidate(dentry, nd);
 }
 
-static int nfs4_create(struct inode *dir, struct dentry *dentry,
-                       umode_t mode, struct nameidata *nd)
-{
-        struct nfs_open_context *ctx = NULL;
-        struct iattr attr;
-        int error;
-        int open_flags = O_CREAT|O_EXCL;
-
-        dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
-                        dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
-
-        attr.ia_mode = mode;
-        attr.ia_valid = ATTR_MODE;
-
-        if (nd)
-                open_flags = nd->intent.open.flags;
-
-        ctx = create_nfs_open_context(dentry, open_flags);
-        error = PTR_ERR(ctx);
-        if (IS_ERR(ctx))
-                goto out_err_drop;
-
-        error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, ctx);
-        if (error != 0)
-                goto out_put_ctx;
-
-        put_nfs_open_context(ctx);
-
-        return 0;
-out_put_ctx:
-        put_nfs_open_context(ctx);
-out_err_drop:
-        d_drop(dentry);
-        return error;
-}
-
 #endif /* CONFIG_NFSV4 */
 
 /*
@@ -1684,7 +1646,7 @@ static int nfs_create(struct inode *dir, struct dentry *dentry,
         if (nd)
                 open_flags = nd->intent.open.flags;
 
-        error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, NULL);
+        error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags);
         if (error != 0)
                 goto out_err;
         return 0;
diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c
index 2292a0fd2bff..3187e24e8f78 100644
--- a/fs/nfs/nfs3proc.c
+++ b/fs/nfs/nfs3proc.c
@@ -314,7 +314,7 @@ static void nfs3_free_createdata(struct nfs3_createdata *data)
  */
 static int
 nfs3_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
-                 int flags, struct nfs_open_context *ctx)
+                 int flags)
 {
         struct nfs3_createdata *data;
         umode_t mode = sattr->ia_mode;
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 15fc7e4664ed..c157b2089b47 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -2806,37 +2806,22 @@ static int nfs4_proc_readlink(struct inode *inode, struct page *page,
 }
 
 /*
- * Got race?
- * We will need to arrange for the VFS layer to provide an atomic open.
- * Until then, this create/open method is prone to inefficiency and race
- * conditions due to the lookup, create, and open VFS calls from sys_open()
- * placed on the wire.
- *
- * Given the above sorry state of affairs, I'm simply sending an OPEN.
- * The file will be opened again in the subsequent VFS open call
- * (nfs4_proc_file_open).
- *
- * The open for read will just hang around to be used by any process that
- * opens the file O_RDONLY. This will all be resolved with the VFS changes.
+ * This is just for mknod.  open(O_CREAT) will always do ->open_context().
  */
-
 static int
 nfs4_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
-                 int flags, struct nfs_open_context *ctx)
+                 int flags)
 {
-        struct dentry *de = dentry;
+        struct nfs_open_context *ctx;
         struct nfs4_state *state;
-        struct rpc_cred *cred = NULL;
-        fmode_t fmode = 0;
         int status = 0;
 
-        if (ctx != NULL) {
-                cred = ctx->cred;
-                de = ctx->dentry;
-                fmode = ctx->mode;
-        }
+        ctx = alloc_nfs_open_context(dentry, FMODE_READ);
+        if (IS_ERR(ctx))
+                return PTR_ERR(ctx);
+
         sattr->ia_mode &= ~current_umask();
-        state = nfs4_do_open(dir, de, fmode, flags, sattr, cred, NULL);
+        state = nfs4_do_open(dir, dentry, ctx->mode, flags, sattr, ctx->cred, NULL);
         d_drop(dentry);
         if (IS_ERR(state)) {
                 status = PTR_ERR(state);
@@ -2844,11 +2829,9 @@ nfs4_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
         }
         d_add(dentry, igrab(state->inode));
         nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
-        if (ctx != NULL)
-                ctx->state = state;
-        else
-                nfs4_close_sync(state, fmode);
+        ctx->state = state;
 out:
+        put_nfs_open_context(ctx);
         return status;
 }
 
diff --git a/fs/nfs/proc.c b/fs/nfs/proc.c
index 617c7419a08e..4433806e116f 100644
--- a/fs/nfs/proc.c
+++ b/fs/nfs/proc.c
@@ -259,7 +259,7 @@ static void nfs_free_createdata(const struct nfs_createdata *data)
 
 static int
 nfs_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
-                int flags, struct nfs_open_context *ctx)
+                int flags)
 {
         struct nfs_createdata *data;
         struct rpc_message msg = {
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 8aadd90b808a..d3b7c18b18f4 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1374,7 +1374,7 @@ struct nfs_rpc_ops {
         int     (*readlink)(struct inode *, struct page *, unsigned int,
                             unsigned int);
         int     (*create)  (struct inode *, struct dentry *,
-                            struct iattr *, int, struct nfs_open_context *);
+                            struct iattr *, int);
         int     (*remove)  (struct inode *, struct qstr *);
         void    (*unlink_setup)  (struct rpc_message *, struct inode *dir);
         void    (*unlink_rpc_prepare) (struct rpc_task *, struct nfs_unlinkdata *);