[PATCH] fs: kill unused ret2 argument from iocb->ki_complete()

[Jens Axboe <axboe@kernel.dk>]

It's not used for anything, and we're wasting time passing in zeroes
where we could just ignore it instead. Update all ki_complete users in
the kernel to drop that last argument.

The exception is the USB gadget code, which passes in non-zero. But
since nobody every looks at ret2, it's still pointless.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

---

diff --git a/block/fops.c b/block/fops.c
index d7eff331a07c..53408271771a 100644
--- a/block/fops.c
+++ b/block/fops.c
@@ -164,7 +164,7 @@ static void blkdev_bio_end_io(struct bio *bio)
 				ret = blk_status_to_errno(dio->bio.bi_status);
 			}
 
-			iocb->ki_complete(iocb, ret, 0);
+			iocb->ki_complete(iocb, ret);
 			if (flags & DIO_MULTI_BIO)
 				bio_put(&dio->bio);
 		} else {
@@ -318,7 +318,7 @@ static void blkdev_bio_end_io_async(struct bio *bio)
 		ret = blk_status_to_errno(bio->bi_status);
 	}
 
-	iocb->ki_complete(iocb, ret, 0);
+	iocb->ki_complete(iocb, ret);
 
 	if (dio->flags & DIO_SHOULD_DIRTY) {
 		bio_check_pages_dirty(bio);
diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index 8bd288d2b089..3dd5a773c320 100644
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c
@@ -1076,7 +1076,7 @@ void af_alg_async_cb(struct crypto_async_request *_req, int err)
 	af_alg_free_resources(areq);
 	sock_put(sk);
 
-	iocb->ki_complete(iocb, err ? err : (int)resultlen, 0);
+	iocb->ki_complete(iocb, err ? err : (int)resultlen);
 }
 EXPORT_SYMBOL_GPL(af_alg_async_cb);
 
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 397bfafc4c25..92b87aa8be86 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -550,7 +550,7 @@ static void lo_rw_aio_do_completion(struct loop_cmd *cmd)
 		blk_mq_complete_request(rq);
 }
 
-static void lo_rw_aio_complete(struct kiocb *iocb, long ret, long ret2)
+static void lo_rw_aio_complete(struct kiocb *iocb, long ret)
 {
 	struct loop_cmd *cmd = container_of(iocb, struct loop_cmd, iocb);
 
@@ -623,7 +623,7 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd,
 	lo_rw_aio_do_completion(cmd);
 
 	if (ret != -EIOCBQUEUED)
-		cmd->iocb.ki_complete(&cmd->iocb, ret, 0);
+		lo_rw_aio_complete(&cmd->iocb, ret);
 	return 0;
 }
 
diff --git a/drivers/nvme/target/io-cmd-file.c b/drivers/nvme/target/io-cmd-file.c
index 7a249b752f3c..80a0f35ae1dc 100644
--- a/drivers/nvme/target/io-cmd-file.c
+++ b/drivers/nvme/target/io-cmd-file.c
@@ -123,7 +123,7 @@ static ssize_t nvmet_file_submit_bvec(struct nvmet_req *req, loff_t pos,
 	return call_iter(iocb, &iter);
 }
 
-static void nvmet_file_io_done(struct kiocb *iocb, long ret, long ret2)
+static void nvmet_file_io_done(struct kiocb *iocb, long ret)
 {
 	struct nvmet_req *req = container_of(iocb, struct nvmet_req, f.iocb);
 	u16 status = NVME_SC_SUCCESS;
@@ -220,7 +220,7 @@ static bool nvmet_file_execute_io(struct nvmet_req *req, int ki_flags)
 	}
 
 complete:
-	nvmet_file_io_done(&req->f.iocb, ret, 0);
+	nvmet_file_io_done(&req->f.iocb, ret);
 	return true;
 }
 
diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c
index b471e726bb3d..968ace2ddf64 100644
--- a/drivers/target/target_core_file.c
+++ b/drivers/target/target_core_file.c
@@ -245,7 +245,7 @@ struct target_core_file_cmd {
 	struct bio_vec	bvecs[];
 };
 
-static void cmd_rw_aio_complete(struct kiocb *iocb, long ret, long ret2)
+static void cmd_rw_aio_complete(struct kiocb *iocb, long ret)
 {
 	struct target_core_file_cmd *cmd;
 
@@ -301,7 +301,7 @@ fd_execute_rw_aio(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 		ret = call_read_iter(file, &aio_cmd->iocb, &iter);
 
 	if (ret != -EIOCBQUEUED)
-		cmd_rw_aio_complete(&aio_cmd->iocb, ret, 0);
+		cmd_rw_aio_complete(&aio_cmd->iocb, ret);
 
 	return 0;
 }
diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index 8260f38025b7..e20c19a0f106 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -831,7 +831,7 @@ static void ffs_user_copy_worker(struct work_struct *work)
 		kthread_unuse_mm(io_data->mm);
 	}
 
-	io_data->kiocb->ki_complete(io_data->kiocb, ret, ret);
+	io_data->kiocb->ki_complete(io_data->kiocb, ret);
 
 	if (io_data->ffs->ffs_eventfd && !kiocb_has_eventfd)
 		eventfd_signal(io_data->ffs->ffs_eventfd, 1);
diff --git a/drivers/usb/gadget/legacy/inode.c b/drivers/usb/gadget/legacy/inode.c
index 539220d7f5b6..ad1739dbfab9 100644
--- a/drivers/usb/gadget/legacy/inode.c
+++ b/drivers/usb/gadget/legacy/inode.c
@@ -469,7 +469,7 @@ static void ep_user_copy_worker(struct work_struct *work)
 		ret = -EFAULT;
 
 	/* completing the iocb can drop the ctx and mm, don't touch mm after */
-	iocb->ki_complete(iocb, ret, ret);
+	iocb->ki_complete(iocb, ret);
 
 	kfree(priv->buf);
 	kfree(priv->to_free);
@@ -499,8 +499,7 @@ static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
 		/* aio_complete() reports bytes-transferred _and_ faults */
 
 		iocb->ki_complete(iocb,
-				req->actual ? req->actual : (long)req->status,
-				req->status);
+				req->actual ? req->actual : (long)req->status);
 	} else {
 		/* ep_copy_to_user() won't report both; we hide some faults */
 		if (unlikely(0 != req->status))
diff --git a/fs/aio.c b/fs/aio.c
index 51b08ab01dff..836dc7e48db7 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1417,7 +1417,7 @@ static void aio_remove_iocb(struct aio_kiocb *iocb)
 	spin_unlock_irqrestore(&ctx->ctx_lock, flags);
 }
 
-static void aio_complete_rw(struct kiocb *kiocb, long res, long res2)
+static void aio_complete_rw(struct kiocb *kiocb, long res)
 {
 	struct aio_kiocb *iocb = container_of(kiocb, struct aio_kiocb, rw);
 
@@ -1437,7 +1437,7 @@ static void aio_complete_rw(struct kiocb *kiocb, long res, long res2)
 	}
 
 	iocb->ki_res.res = res;
-	iocb->ki_res.res2 = res2;
+	iocb->ki_res.res2 = 0;
 	iocb_put(iocb);
 }
 
@@ -1508,7 +1508,7 @@ static inline void aio_rw_done(struct kiocb *req, ssize_t ret)
 		ret = -EINTR;
 		fallthrough;
 	default:
-		req->ki_complete(req, ret, 0);
+		req->ki_complete(req, ret);
 	}
 }
 
diff --git a/fs/cachefiles/io.c b/fs/cachefiles/io.c
index fac2e8e7b533..effe37ef8629 100644
--- a/fs/cachefiles/io.c
+++ b/fs/cachefiles/io.c
@@ -37,11 +37,11 @@ static inline void cachefiles_put_kiocb(struct cachefiles_kiocb *ki)
 /*
  * Handle completion of a read from the cache.
  */
-static void cachefiles_read_complete(struct kiocb *iocb, long ret, long ret2)
+static void cachefiles_read_complete(struct kiocb *iocb, long ret)
 {
 	struct cachefiles_kiocb *ki = container_of(iocb, struct cachefiles_kiocb, iocb);
 
-	_enter("%ld,%ld", ret, ret2);
+	_enter("%ld", ret);
 
 	if (ki->term_func) {
 		if (ret >= 0)
@@ -139,7 +139,7 @@ static int cachefiles_read(struct netfs_cache_resources *cres,
 		fallthrough;
 	default:
 		ki->was_async = false;
-		cachefiles_read_complete(&ki->iocb, ret, 0);
+		cachefiles_read_complete(&ki->iocb, ret);
 		if (ret > 0)
 			ret = 0;
 		break;
@@ -159,12 +159,12 @@ static int cachefiles_read(struct netfs_cache_resources *cres,
 /*
  * Handle completion of a write to the cache.
  */
-static void cachefiles_write_complete(struct kiocb *iocb, long ret, long ret2)
+static void cachefiles_write_complete(struct kiocb *iocb, long ret)
 {
 	struct cachefiles_kiocb *ki = container_of(iocb, struct cachefiles_kiocb, iocb);
 	struct inode *inode = file_inode(ki->iocb.ki_filp);
 
-	_enter("%ld,%ld", ret, ret2);
+	_enter("%ld", ret);
 
 	/* Tell lockdep we inherited freeze protection from submission thread */
 	__sb_writers_acquired(inode->i_sb, SB_FREEZE_WRITE);
@@ -244,7 +244,7 @@ static int cachefiles_write(struct netfs_cache_resources *cres,
 		fallthrough;
 	default:
 		ki->was_async = false;
-		cachefiles_write_complete(&ki->iocb, ret, 0);
+		cachefiles_write_complete(&ki->iocb, ret);
 		if (ret > 0)
 			ret = 0;
 		break;
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 5c1954ff3a82..41f4ca038191 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -1022,7 +1022,7 @@ static void ceph_aio_complete(struct inode *inode,
 	ceph_put_cap_refs(ci, (aio_req->write ? CEPH_CAP_FILE_WR :
 						CEPH_CAP_FILE_RD));
 
-	aio_req->iocb->ki_complete(aio_req->iocb, ret, 0);
+	aio_req->iocb->ki_complete(aio_req->iocb, ret);
 
 	ceph_free_cap_flush(aio_req->prealloc_cf);
 	kfree(aio_req);
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 13f3182cf796..1b855fcb179e 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -3184,7 +3184,7 @@ static void collect_uncached_write_data(struct cifs_aio_ctx *ctx)
 	mutex_unlock(&ctx->aio_mutex);
 
 	if (ctx->iocb && ctx->iocb->ki_complete)
-		ctx->iocb->ki_complete(ctx->iocb, ctx->rc, 0);
+		ctx->iocb->ki_complete(ctx->iocb, ctx->rc);
 	else
 		complete(&ctx->done);
 }
@@ -3917,7 +3917,7 @@ collect_uncached_read_data(struct cifs_aio_ctx *ctx)
 	mutex_unlock(&ctx->aio_mutex);
 
 	if (ctx->iocb && ctx->iocb->ki_complete)
-		ctx->iocb->ki_complete(ctx->iocb, ctx->rc, 0);
+		ctx->iocb->ki_complete(ctx->iocb, ctx->rc);
 	else
 		complete(&ctx->done);
 }
diff --git a/fs/direct-io.c b/fs/direct-io.c
index 453dcff0e7f5..654443558047 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -307,7 +307,7 @@ static ssize_t dio_complete(struct dio *dio, ssize_t ret, unsigned int flags)
 
 		if (ret > 0 && dio->op == REQ_OP_WRITE)
 			ret = generic_write_sync(dio->iocb, ret);
-		dio->iocb->ki_complete(dio->iocb, ret, 0);
+		dio->iocb->ki_complete(dio->iocb, ret);
 	}
 
 	kmem_cache_free(dio_cache, dio);
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 11404f8c21c7..e6039f22311b 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -687,7 +687,7 @@ static void fuse_aio_complete(struct fuse_io_priv *io, int err, ssize_t pos)
 			spin_unlock(&fi->lock);
 		}
 
-		io->iocb->ki_complete(io->iocb, res, 0);
+		io->iocb->ki_complete(io->iocb, res);
 	}
 
 	kref_put(&io->refcnt, fuse_io_release);
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 5edde3b2f72d..5ad046145f29 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2672,7 +2672,7 @@ static void __io_complete_rw(struct io_kiocb *req, long res, long res2,
 	__io_req_complete(req, issue_flags, req->result, io_put_rw_kbuf(req));
 }
 
-static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
+static void io_complete_rw(struct kiocb *kiocb, long res)
 {
 	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
 
@@ -2683,7 +2683,7 @@ static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
 	io_req_task_work_add(req);
 }
 
-static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2)
+static void io_complete_rw_iopoll(struct kiocb *kiocb, long res)
 {
 	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
 
@@ -2891,7 +2891,7 @@ static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret)
 		ret = -EINTR;
 		fallthrough;
 	default:
-		kiocb->ki_complete(kiocb, ret, 0);
+		kiocb->ki_complete(kiocb, ret);
 	}
 }
 
diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
index 83ecfba53abe..811c898125a5 100644
--- a/fs/iomap/direct-io.c
+++ b/fs/iomap/direct-io.c
@@ -125,7 +125,7 @@ static void iomap_dio_complete_work(struct work_struct *work)
 	struct iomap_dio *dio = container_of(work, struct iomap_dio, aio.work);
 	struct kiocb *iocb = dio->iocb;
 
-	iocb->ki_complete(iocb, iomap_dio_complete(dio), 0);
+	iocb->ki_complete(iocb, iomap_dio_complete(dio));
 }
 
 /*
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 2e894fec036b..7a5f287c5391 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -275,7 +275,7 @@ static void nfs_direct_complete(struct nfs_direct_req *dreq)
 			res = (long) dreq->count;
 			WARN_ON_ONCE(dreq->count < 0);
 		}
-		dreq->iocb->ki_complete(dreq->iocb, res, 0);
+		dreq->iocb->ki_complete(dreq->iocb, res);
 	}
 
 	complete(&dreq->completion);
diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index c88ac571593d..ac461a499882 100644
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -272,14 +272,14 @@ static void ovl_aio_cleanup_handler(struct ovl_aio_req *aio_req)
 	kmem_cache_free(ovl_aio_request_cachep, aio_req);
 }
 
-static void ovl_aio_rw_complete(struct kiocb *iocb, long res, long res2)
+static void ovl_aio_rw_complete(struct kiocb *iocb, long res)
 {
 	struct ovl_aio_req *aio_req = container_of(iocb,
 						   struct ovl_aio_req, iocb);
 	struct kiocb *orig_iocb = aio_req->orig_iocb;
 
 	ovl_aio_cleanup_handler(aio_req);
-	orig_iocb->ki_complete(orig_iocb, res, res2);
+	orig_iocb->ki_complete(orig_iocb, res);
 }
 
 static ssize_t ovl_read_iter(struct kiocb *iocb, struct iov_iter *iter)
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 31029a91f440..0dcb9020a7b3 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -330,7 +330,7 @@ struct kiocb {
 	randomized_struct_fields_start
 
 	loff_t			ki_pos;
-	void (*ki_complete)(struct kiocb *iocb, long ret, long ret2);
+	void (*ki_complete)(struct kiocb *iocb, long ret);
 	void			*private;
 	int			ki_flags;
 	u16			ki_hint;

-- 
Jens Axboe