nfs: generic_write_checks() shouldn't be done on swapout...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/nfs/direct.c

@@ -268,7 +268,7 @@ ssize_t nfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter, loff_t pos)
 
 	if (iov_iter_rw(iter) == READ)
 		return nfs_file_direct_read(iocb, iter, pos);
-	return nfs_file_direct_write(iocb, iter, pos);
+	return nfs_file_direct_write(iocb, iter);
 #endif /* CONFIG_NFS_SWAP */
 }
 
@@ -959,24 +959,19 @@ static ssize_t nfs_direct_write_schedule_iovec(struct nfs_direct_req *dreq,
  * Note that O_APPEND is not supported for NFS direct writes, as there
  * is no atomic O_APPEND write facility in the NFS protocol.
  */
-ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter,
-				loff_t pos)
+ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter)
 {
 	ssize_t result = -EINVAL;
 	struct file *file = iocb->ki_filp;
 	struct address_space *mapping = file->f_mapping;
 	struct inode *inode = mapping->host;
 	struct nfs_direct_req *dreq;
 	struct nfs_lock_context *l_ctx;
-	loff_t end;
+	loff_t pos, end;
 
 	dfprintk(FILE, "NFS: direct write(%pD2, %zd@%Ld)\n",
 		file, iov_iter_count(iter), (long long) iocb->ki_pos);
 
-	result = generic_write_checks(iocb, iter);
-	if (result <= 0)
-		goto out;
-
 	nfs_add_stats(mapping->host, NFSIOS_DIRECTWRITTENBYTES,
 		      iov_iter_count(iter));
 
@@ -1044,7 +1039,6 @@ ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter,
 	nfs_direct_req_release(dreq);
 out_unlock:
 	mutex_unlock(&inode->i_mutex);
-out:
 	return result;
 }
 

fs/nfs/file.c

@@ -674,17 +674,20 @@ ssize_t nfs_file_write(struct kiocb *iocb, struct iov_iter *from)
 	unsigned long written = 0;
 	ssize_t result;
 	size_t count = iov_iter_count(from);
-	loff_t pos = iocb->ki_pos;
 
 	result = nfs_key_timeout_notify(file, inode);
 	if (result)
 		return result;
 
-	if (iocb->ki_flags & IOCB_DIRECT)
-		return nfs_file_direct_write(iocb, from, pos);
+	if (iocb->ki_flags & IOCB_DIRECT) {
+		result = generic_write_checks(iocb, from);
+		if (result <= 0)
+			return result;
+		return nfs_file_direct_write(iocb, from);
+	}
 
 	dprintk("NFS: write(%pD2, %zu@%Ld)\n",
-		file, count, (long long) pos);
+		file, count, (long long) iocb->ki_pos);
 
 	result = -EBUSY;
 	if (IS_SWAPFILE(inode))

include/linux/nfs_fs.h

@@ -452,8 +452,7 @@ extern ssize_t nfs_file_direct_read(struct kiocb *iocb,
 			struct iov_iter *iter,
 			loff_t pos);
 extern ssize_t nfs_file_direct_write(struct kiocb *iocb,
-			struct iov_iter *iter,
-			loff_t pos);
+			struct iov_iter *iter);
 
 /*
  * linux/fs/nfs/dir.c