use less confusing names for iov_iter direction initializers

READ/WRITE proved to be actively confusing - the meanings are
"data destination, as used with read(2)" and "data source, as
used with write(2)", but people keep interpreting those as
"we read data from it" and "we write data to it", i.e. exactly
the wrong way.

Call them ITER_DEST and ITER_SOURCE - at least that is harder
to misinterpret...

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

2 files changed, 12 insertions, 12 deletions

diff --git a/io_uring/net.c b/io_uring/net.c
index ab83da7e80f0..2818aeefea42 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -363,7 +363,7 @@ int io_send(struct io_kiocb *req, unsigned int issue_flags)
 	if (unlikely(!sock))
 		return -ENOTSOCK;
 
-	ret = import_single_range(WRITE, sr->buf, sr->len, &iov, &msg.msg_iter);
+	ret = import_single_range(ITER_SOURCE, sr->buf, sr->len, &iov, &msg.msg_iter);
 	if (unlikely(ret))
 		return ret;
 
@@ -449,7 +449,7 @@ static int __io_recvmsg_copy_hdr(struct io_kiocb *req,
 		}
 	} else {
 		iomsg->free_iov = iomsg->fast_iov;
-		ret = __import_iovec(READ, msg.msg_iov, msg.msg_iovlen, UIO_FASTIOV,
+		ret = __import_iovec(ITER_DEST, msg.msg_iov, msg.msg_iovlen, UIO_FASTIOV,
 				     &iomsg->free_iov, &iomsg->msg.msg_iter,
 				     false);
 		if (ret > 0)
@@ -501,7 +501,7 @@ static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req,
 		}
 	} else {
 		iomsg->free_iov = iomsg->fast_iov;
-		ret = __import_iovec(READ, (struct iovec __user *)uiov, msg.msg_iovlen,
+		ret = __import_iovec(ITER_DEST, (struct iovec __user *)uiov, msg.msg_iovlen,
 				   UIO_FASTIOV, &iomsg->free_iov,
 				   &iomsg->msg.msg_iter, true);
 		if (ret < 0)
@@ -751,7 +751,7 @@ retry_multishot:
 
 		kmsg->fast_iov[0].iov_base = buf;
 		kmsg->fast_iov[0].iov_len = len;
-		iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->fast_iov, 1,
+		iov_iter_init(&kmsg->msg.msg_iter, ITER_DEST, kmsg->fast_iov, 1,
 				len);
 	}
 
@@ -845,7 +845,7 @@ retry_multishot:
 		sr->buf = buf;
 	}
 
-	ret = import_single_range(READ, sr->buf, len, &iov, &msg.msg_iter);
+	ret = import_single_range(ITER_DEST, sr->buf, len, &iov, &msg.msg_iter);
 	if (unlikely(ret))
 		goto out_free;
 
@@ -1081,13 +1081,13 @@ int io_send_zc(struct io_kiocb *req, unsigned int issue_flags)
 		return io_setup_async_addr(req, &__address, issue_flags);
 
 	if (zc->flags & IORING_RECVSEND_FIXED_BUF) {
-		ret = io_import_fixed(WRITE, &msg.msg_iter, req->imu,
+		ret = io_import_fixed(ITER_SOURCE, &msg.msg_iter, req->imu,
 					(u64)(uintptr_t)zc->buf, zc->len);
 		if (unlikely(ret))
 			return ret;
 		msg.sg_from_iter = io_sg_from_iter;
 	} else {
-		ret = import_single_range(WRITE, zc->buf, zc->len, &iov,
+		ret = import_single_range(ITER_SOURCE, zc->buf, zc->len, &iov,
 					  &msg.msg_iter);
 		if (unlikely(ret))
 			return ret;
diff --git a/io_uring/rw.c b/io_uring/rw.c
index bb47cc4da713..fed5570be335 100644
--- a/io_uring/rw.c
+++ b/io_uring/rw.c
@@ -548,12 +548,12 @@ static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
 
 int io_readv_prep_async(struct io_kiocb *req)
 {
-	return io_rw_prep_async(req, READ);
+	return io_rw_prep_async(req, ITER_DEST);
 }
 
 int io_writev_prep_async(struct io_kiocb *req)
 {
-	return io_rw_prep_async(req, WRITE);
+	return io_rw_prep_async(req, ITER_SOURCE);
 }
 
 /*
@@ -704,7 +704,7 @@ int io_read(struct io_kiocb *req, unsigned int issue_flags)
 	loff_t *ppos;
 
 	if (!req_has_async_data(req)) {
-		ret = io_import_iovec(READ, req, &iovec, s, issue_flags);
+		ret = io_import_iovec(ITER_DEST, req, &iovec, s, issue_flags);
 		if (unlikely(ret < 0))
 			return ret;
 	} else {
@@ -716,7 +716,7 @@ int io_read(struct io_kiocb *req, unsigned int issue_flags)
 		 * buffers, as we dropped the selected one before retry.
 		 */
 		if (io_do_buffer_select(req)) {
-			ret = io_import_iovec(READ, req, &iovec, s, issue_flags);
+			ret = io_import_iovec(ITER_DEST, req, &iovec, s, issue_flags);
 			if (unlikely(ret < 0))
 				return ret;
 		}
@@ -851,7 +851,7 @@ int io_write(struct io_kiocb *req, unsigned int issue_flags)
 	loff_t *ppos;
 
 	if (!req_has_async_data(req)) {
-		ret = io_import_iovec(WRITE, req, &iovec, s, issue_flags);
+		ret = io_import_iovec(ITER_SOURCE, req, &iovec, s, issue_flags);
 		if (unlikely(ret < 0))
 			return ret;
 	} else {