Merge tag 'pull-iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull iov_iter updates from Al Viro:
 "iov_iter work; most of that is about getting rid of direction
  misannotations and (hopefully) preventing more of the same for the
  future"

* tag 'pull-iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  use less confusing names for iov_iter direction initializers
  iov_iter: saner checks for attempt to copy to/from iterator
  [xen] fix "direction" argument of iov_iter_kvec()
  [vhost] fix 'direction' argument of iov_iter_{init,bvec}()
  [target] fix iov_iter_bvec() "direction" argument
  [s390] memcpy_real(): WRITE is "data source", not destination...
  [s390] zcore: WRITE is "data source", not destination...
  [infiniband] READ is "data destination", not source...
  [fsi] WRITE is "data source", not destination...
  [s390] copy_oldmem_kernel() - WRITE is "data source", not destination
  csum_and_copy_to_iter(): handle ITER_DISCARD
  get rid of unlikely() on page_copy_sane() calls

31 files changed, 72 insertions, 72 deletions

diff --git a/fs/9p/vfs_addr.c b/fs/9p/vfs_addr.c
index 47b9a1122f34..a19891015f19 100644
--- a/fs/9p/vfs_addr.c
+++ b/fs/9p/vfs_addr.c
@@ -40,7 +40,7 @@ static void v9fs_issue_read(struct netfs_io_subrequest *subreq)
 	size_t len = subreq->len   - subreq->transferred;
 	int total, err;
 
-	iov_iter_xarray(&to, READ, &rreq->mapping->i_pages, pos, len);
+	iov_iter_xarray(&to, ITER_DEST, &rreq->mapping->i_pages, pos, len);
 
 	total = p9_client_read(fid, pos, &to, &err);
 
@@ -172,7 +172,7 @@ static int v9fs_vfs_write_folio_locked(struct folio *folio)
 
 	len = min_t(loff_t, i_size - start, len);
 
-	iov_iter_xarray(&from, WRITE, &folio_mapping(folio)->i_pages, start, len);
+	iov_iter_xarray(&from, ITER_SOURCE, &folio_mapping(folio)->i_pages, start, len);
 
 	/* We should have writeback_fid always set */
 	BUG_ON(!v9inode->writeback_fid);
diff --git a/fs/9p/vfs_dir.c b/fs/9p/vfs_dir.c
index 000fbaae9b18..3bb95adc9619 100644
--- a/fs/9p/vfs_dir.c
+++ b/fs/9p/vfs_dir.c
@@ -109,7 +109,7 @@ static int v9fs_dir_readdir(struct file *file, struct dir_context *ctx)
 			struct iov_iter to;
 			int n;
 
-			iov_iter_kvec(&to, READ, &kvec, 1, buflen);
+			iov_iter_kvec(&to, ITER_DEST, &kvec, 1, buflen);
 			n = p9_client_read(file->private_data, ctx->pos, &to,
 					   &err);
 			if (err)
diff --git a/fs/9p/xattr.c b/fs/9p/xattr.c
index 1f9298a4bd42..2807bb63f780 100644
--- a/fs/9p/xattr.c
+++ b/fs/9p/xattr.c
@@ -24,7 +24,7 @@ ssize_t v9fs_fid_xattr_get(struct p9_fid *fid, const char *name,
 	struct iov_iter to;
 	int err;
 
-	iov_iter_kvec(&to, READ, &kvec, 1, buffer_size);
+	iov_iter_kvec(&to, ITER_DEST, &kvec, 1, buffer_size);
 
 	attr_fid = p9_client_xattrwalk(fid, name, &attr_size);
 	if (IS_ERR(attr_fid)) {
@@ -109,7 +109,7 @@ int v9fs_fid_xattr_set(struct p9_fid *fid, const char *name,
 	struct iov_iter from;
 	int retval, err;
 
-	iov_iter_kvec(&from, WRITE, &kvec, 1, value_len);
+	iov_iter_kvec(&from, ITER_SOURCE, &kvec, 1, value_len);
 
 	p9_debug(P9_DEBUG_VFS, "name = %s value_len = %zu flags = %d\n",
 		 name, value_len, flags);
diff --git a/fs/afs/cmservice.c b/fs/afs/cmservice.c
index 0a090d614e76..7dcd59693a0c 100644
--- a/fs/afs/cmservice.c
+++ b/fs/afs/cmservice.c
@@ -298,7 +298,7 @@ static int afs_deliver_cb_callback(struct afs_call *call)
 		if (call->count2 != call->count && call->count2 != 0)
 			return afs_protocol_error(call, afs_eproto_cb_count);
 		call->iter = &call->def_iter;
-		iov_iter_discard(&call->def_iter, READ, call->count2 * 3 * 4);
+		iov_iter_discard(&call->def_iter, ITER_DEST, call->count2 * 3 * 4);
 		call->unmarshall++;
 
 		fallthrough;
diff --git a/fs/afs/dir.c b/fs/afs/dir.c
index 230c2d19116d..104df2964225 100644
--- a/fs/afs/dir.c
+++ b/fs/afs/dir.c
@@ -305,7 +305,7 @@ expand:
 	req->actual_len = i_size; /* May change */
 	req->len = nr_pages * PAGE_SIZE; /* We can ask for more than there is */
 	req->data_version = dvnode->status.data_version; /* May change */
-	iov_iter_xarray(&req->def_iter, READ, &dvnode->netfs.inode.i_mapping->i_pages,
+	iov_iter_xarray(&req->def_iter, ITER_DEST, &dvnode->netfs.inode.i_mapping->i_pages,
 			0, i_size);
 	req->iter = &req->def_iter;
 
diff --git a/fs/afs/file.c b/fs/afs/file.c
index d1cfb235c4b9..2eeab57df133 100644
--- a/fs/afs/file.c
+++ b/fs/afs/file.c
@@ -324,7 +324,7 @@ static void afs_issue_read(struct netfs_io_subrequest *subreq)
 	fsreq->vnode	= vnode;
 	fsreq->iter	= &fsreq->def_iter;
 
-	iov_iter_xarray(&fsreq->def_iter, READ,
+	iov_iter_xarray(&fsreq->def_iter, ITER_DEST,
 			&fsreq->vnode->netfs.inode.i_mapping->i_pages,
 			fsreq->pos, fsreq->len);
 
@@ -346,7 +346,7 @@ static int afs_symlink_read_folio(struct file *file, struct folio *folio)
 	fsreq->len	= folio_size(folio);
 	fsreq->vnode	= vnode;
 	fsreq->iter	= &fsreq->def_iter;
-	iov_iter_xarray(&fsreq->def_iter, READ, &folio->mapping->i_pages,
+	iov_iter_xarray(&fsreq->def_iter, ITER_DEST, &folio->mapping->i_pages,
 			fsreq->pos, fsreq->len);
 
 	ret = afs_fetch_data(fsreq->vnode, fsreq);
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index 723d162078a3..9ba7b68375c9 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -1301,7 +1301,7 @@ static inline void afs_extract_begin(struct afs_call *call, void *buf, size_t si
 	call->iov_len = size;
 	call->kvec[0].iov_base = buf;
 	call->kvec[0].iov_len = size;
-	iov_iter_kvec(&call->def_iter, READ, call->kvec, 1, size);
+	iov_iter_kvec(&call->def_iter, ITER_DEST, call->kvec, 1, size);
 }
 
 static inline void afs_extract_to_tmp(struct afs_call *call)
@@ -1319,7 +1319,7 @@ static inline void afs_extract_to_tmp64(struct afs_call *call)
 static inline void afs_extract_discard(struct afs_call *call, size_t size)
 {
 	call->iov_len = size;
-	iov_iter_discard(&call->def_iter, READ, size);
+	iov_iter_discard(&call->def_iter, ITER_DEST, size);
 }
 
 static inline void afs_extract_to_buf(struct afs_call *call, size_t size)
diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c
index eccc3cd0cb70..c62939e5ea1f 100644
--- a/fs/afs/rxrpc.c
+++ b/fs/afs/rxrpc.c
@@ -359,7 +359,7 @@ void afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call, gfp_t gfp)
 
 	msg.msg_name		= NULL;
 	msg.msg_namelen		= 0;
-	iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, call->request_size);
+	iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, iov, 1, call->request_size);
 	msg.msg_control		= NULL;
 	msg.msg_controllen	= 0;
 	msg.msg_flags		= MSG_WAITALL | (call->write_iter ? MSG_MORE : 0);
@@ -400,7 +400,7 @@ error_do_abort:
 					RX_USER_ABORT, ret, "KSD");
 	} else {
 		len = 0;
-		iov_iter_kvec(&msg.msg_iter, READ, NULL, 0, 0);
+		iov_iter_kvec(&msg.msg_iter, ITER_DEST, NULL, 0, 0);
 		rxrpc_kernel_recv_data(call->net->socket, rxcall,
 				       &msg.msg_iter, &len, false,
 				       &call->abort_code, &call->service_id);
@@ -485,7 +485,7 @@ static void afs_deliver_to_call(struct afs_call *call)
 	       ) {
 		if (state == AFS_CALL_SV_AWAIT_ACK) {
 			len = 0;
-			iov_iter_kvec(&call->def_iter, READ, NULL, 0, 0);
+			iov_iter_kvec(&call->def_iter, ITER_DEST, NULL, 0, 0);
 			ret = rxrpc_kernel_recv_data(call->net->socket,
 						     call->rxcall, &call->def_iter,
 						     &len, false, &remote_abort,
@@ -822,7 +822,7 @@ void afs_send_empty_reply(struct afs_call *call)
 
 	msg.msg_name		= NULL;
 	msg.msg_namelen		= 0;
-	iov_iter_kvec(&msg.msg_iter, WRITE, NULL, 0, 0);
+	iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, NULL, 0, 0);
 	msg.msg_control		= NULL;
 	msg.msg_controllen	= 0;
 	msg.msg_flags		= 0;
@@ -862,7 +862,7 @@ void afs_send_simple_reply(struct afs_call *call, const void *buf, size_t len)
 	iov[0].iov_len		= len;
 	msg.msg_name		= NULL;
 	msg.msg_namelen		= 0;
-	iov_iter_kvec(&msg.msg_iter, WRITE, iov, 1, len);
+	iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, iov, 1, len);
 	msg.msg_control		= NULL;
 	msg.msg_controllen	= 0;
 	msg.msg_flags		= 0;
diff --git a/fs/afs/write.c b/fs/afs/write.c
index 9ebdd36eaf2f..08fd456dde67 100644
--- a/fs/afs/write.c
+++ b/fs/afs/write.c
@@ -609,7 +609,7 @@ static ssize_t afs_write_back_from_locked_folio(struct address_space *mapping,
 		 */
 		afs_write_to_cache(vnode, start, len, i_size, caching);
 
-		iov_iter_xarray(&iter, WRITE, &mapping->i_pages, start, len);
+		iov_iter_xarray(&iter, ITER_SOURCE, &mapping->i_pages, start, len);
 		ret = afs_store_data(vnode, &iter, start, false);
 	} else {
 		_debug("write discard %x @%llx [%llx]", len, start, i_size);
@@ -1000,7 +1000,7 @@ int afs_launder_folio(struct folio *folio)
 		bv[0].bv_page = &folio->page;
 		bv[0].bv_offset = f;
 		bv[0].bv_len = t - f;
-		iov_iter_bvec(&iter, WRITE, bv, 1, bv[0].bv_len);
+		iov_iter_bvec(&iter, ITER_SOURCE, bv, 1, bv[0].bv_len);
 
 		trace_afs_folio_dirty(vnode, tracepoint_string("launder"), folio);
 		ret = afs_store_data(vnode, &iter, folio_pos(folio) + f, true);
diff --git a/fs/aio.c b/fs/aio.c
index 5b2ff20ad322..562916d85cba 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1552,7 +1552,7 @@ static int aio_read(struct kiocb *req, const struct iocb *iocb,
 	if (unlikely(!file->f_op->read_iter))
 		return -EINVAL;
 
-	ret = aio_setup_rw(READ, iocb, &iovec, vectored, compat, &iter);
+	ret = aio_setup_rw(ITER_DEST, iocb, &iovec, vectored, compat, &iter);
 	if (ret < 0)
 		return ret;
 	ret = rw_verify_area(READ, file, &req->ki_pos, iov_iter_count(&iter));
@@ -1580,7 +1580,7 @@ static int aio_write(struct kiocb *req, const struct iocb *iocb,
 	if (unlikely(!file->f_op->write_iter))
 		return -EINVAL;
 
-	ret = aio_setup_rw(WRITE, iocb, &iovec, vectored, compat, &iter);
+	ret = aio_setup_rw(ITER_SOURCE, iocb, &iovec, vectored, compat, &iter);
 	if (ret < 0)
 		return ret;
 	ret = rw_verify_area(WRITE, file, &req->ki_pos, iov_iter_count(&iter));
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 5ba2e810dc6e..f897be9ec1e9 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -5286,7 +5286,7 @@ static int btrfs_ioctl_encoded_read(struct file *file, void __user *argp,
 		goto out_acct;
 	}
 
-	ret = import_iovec(READ, args.iov, args.iovcnt, ARRAY_SIZE(iovstack),
+	ret = import_iovec(ITER_DEST, args.iov, args.iovcnt, ARRAY_SIZE(iovstack),
 			   &iov, &iter);
 	if (ret < 0)
 		goto out_acct;
@@ -5385,7 +5385,7 @@ static int btrfs_ioctl_encoded_write(struct file *file, void __user *argp, bool
 	if (args.len > args.unencoded_len - args.unencoded_offset)
 		goto out_acct;
 
-	ret = import_iovec(WRITE, args.iov, args.iovcnt, ARRAY_SIZE(iovstack),
+	ret = import_iovec(ITER_SOURCE, args.iov, args.iovcnt, ARRAY_SIZE(iovstack),
 			   &iov, &iter);
 	if (ret < 0)
 		goto out_acct;
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index dcf701b05cc1..61f47debec5a 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -288,7 +288,7 @@ static bool ceph_netfs_issue_op_inline(struct netfs_io_subrequest *subreq)
 	}
 
 	len = min_t(size_t, iinfo->inline_len - subreq->start, subreq->len);
-	iov_iter_xarray(&iter, READ, &rreq->mapping->i_pages, subreq->start, len);
+	iov_iter_xarray(&iter, ITER_DEST, &rreq->mapping->i_pages, subreq->start, len);
 	err = copy_to_iter(iinfo->inline_data + subreq->start, len, &iter);
 	if (err == 0)
 		err = -EFAULT;
@@ -327,7 +327,7 @@ static void ceph_netfs_issue_read(struct netfs_io_subrequest *subreq)
 	}
 
 	dout("%s: pos=%llu orig_len=%zu len=%llu\n", __func__, subreq->start, subreq->len, len);
-	iov_iter_xarray(&iter, READ, &rreq->mapping->i_pages, subreq->start, len);
+	iov_iter_xarray(&iter, ITER_DEST, &rreq->mapping->i_pages, subreq->start, len);
 	err = iov_iter_get_pages_alloc2(&iter, &pages, len, &page_off);
 	if (err < 0) {
 		dout("%s: iov_ter_get_pages_alloc returned %d\n", __func__, err);
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 04fd34557de8..6f9580defb2b 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -1161,7 +1161,7 @@ static void ceph_aio_complete_req(struct ceph_osd_request *req)
 				aio_req->total_len = rc + zlen;
 			}
 
-			iov_iter_bvec(&i, READ, osd_data->bvec_pos.bvecs,
+			iov_iter_bvec(&i, ITER_DEST, osd_data->bvec_pos.bvecs,
 				      osd_data->num_bvecs, len);
 			iov_iter_advance(&i, rc);
 			iov_iter_zero(zlen, &i);
@@ -1400,7 +1400,7 @@ ceph_direct_read_write(struct kiocb *iocb, struct iov_iter *iter,
 				int zlen = min_t(size_t, len - ret,
 						 size - pos - ret);
 
-				iov_iter_bvec(&i, READ, bvecs, num_pages, len);
+				iov_iter_bvec(&i, ITER_DEST, bvecs, num_pages, len);
 				iov_iter_advance(&i, ret);
 				iov_iter_zero(zlen, &i);
 				ret += zlen;
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 9db9527c61cf..e80252a83225 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -759,7 +759,7 @@ cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
 {
 	struct msghdr smb_msg = {};
 	struct kvec iov = {.iov_base = buf, .iov_len = to_read};
-	iov_iter_kvec(&smb_msg.msg_iter, READ, &iov, 1, to_read);
+	iov_iter_kvec(&smb_msg.msg_iter, ITER_DEST, &iov, 1, to_read);
 
 	return cifs_readv_from_socket(server, &smb_msg);
 }
@@ -774,7 +774,7 @@ cifs_discard_from_socket(struct TCP_Server_Info *server, size_t to_read)
 	 *  and cifs_readv_from_socket sets msg_control and msg_controllen
 	 *  so little to initialize in struct msghdr
 	 */
-	iov_iter_discard(&smb_msg.msg_iter, READ, to_read);
+	iov_iter_discard(&smb_msg.msg_iter, ITER_DEST, to_read);
 
 	return cifs_readv_from_socket(server, &smb_msg);
 }
@@ -786,7 +786,7 @@ cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page,
 	struct msghdr smb_msg = {};
 	struct bio_vec bv = {
 		.bv_page = page, .bv_len = to_read, .bv_offset = page_offset};
-	iov_iter_bvec(&smb_msg.msg_iter, READ, &bv, 1, to_read);
+	iov_iter_bvec(&smb_msg.msg_iter, ITER_DEST, &bv, 1, to_read);
 	return cifs_readv_from_socket(server, &smb_msg);
 }
 
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 6c1431979495..87b56b1ae117 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -3532,7 +3532,7 @@ static ssize_t __cifs_writev(
 		ctx->iter = *from;
 		ctx->len = len;
 	} else {
-		rc = setup_aio_ctx_iter(ctx, from, WRITE);
+		rc = setup_aio_ctx_iter(ctx, from, ITER_SOURCE);
 		if (rc) {
 			kref_put(&ctx->refcount, cifs_aio_ctx_release);
 			return rc;
@@ -4276,7 +4276,7 @@ static ssize_t __cifs_readv(
 		ctx->iter = *to;
 		ctx->len = len;
 	} else {
-		rc = setup_aio_ctx_iter(ctx, to, READ);
+		rc = setup_aio_ctx_iter(ctx, to, ITER_DEST);
 		if (rc) {
 			kref_put(&ctx->refcount, cifs_aio_ctx_release);
 			return rc;
diff --git a/fs/cifs/fscache.c b/fs/cifs/fscache.c
index a1751b956318..f6f3a6b75601 100644
--- a/fs/cifs/fscache.c
+++ b/fs/cifs/fscache.c
@@ -150,7 +150,7 @@ static int fscache_fallback_read_page(struct inode *inode, struct page *page)
 	bvec[0].bv_page		= page;
 	bvec[0].bv_offset	= 0;
 	bvec[0].bv_len		= PAGE_SIZE;
-	iov_iter_bvec(&iter, READ, bvec, ARRAY_SIZE(bvec), PAGE_SIZE);
+	iov_iter_bvec(&iter, ITER_DEST, bvec, ARRAY_SIZE(bvec), PAGE_SIZE);
 
 	ret = fscache_begin_read_operation(&cres, cookie);
 	if (ret < 0)
@@ -180,7 +180,7 @@ static int fscache_fallback_write_page(struct inode *inode, struct page *page,
 	bvec[0].bv_page		= page;
 	bvec[0].bv_offset	= 0;
 	bvec[0].bv_len		= PAGE_SIZE;
-	iov_iter_bvec(&iter, WRITE, bvec, ARRAY_SIZE(bvec), PAGE_SIZE);
+	iov_iter_bvec(&iter, ITER_SOURCE, bvec, ARRAY_SIZE(bvec), PAGE_SIZE);
 
 	ret = fscache_begin_write_operation(&cres, cookie);
 	if (ret < 0)
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index bfaafd02fb1f..32b3877b538a 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -4723,13 +4723,13 @@ handle_read_data(struct TCP_Server_Info *server, struct mid_q_entry *mid,
 			return 0;
 		}
 
-		iov_iter_bvec(&iter, WRITE, bvec, npages, data_len);
+		iov_iter_bvec(&iter, ITER_SOURCE, bvec, npages, data_len);
 	} else if (buf_len >= data_offset + data_len) {
 		/* read response payload is in buf */
 		WARN_ONCE(npages > 0, "read data can be either in buf or in pages");
 		iov.iov_base = buf + data_offset;
 		iov.iov_len = data_len;
-		iov_iter_kvec(&iter, WRITE, &iov, 1, data_len);
+		iov_iter_kvec(&iter, ITER_SOURCE, &iov, 1, data_len);
 	} else {
 		/* read response payload cannot be in both buf and pages */
 		WARN_ONCE(1, "buf can not contain only a part of read data");
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 575fa8f58342..3851d0aaa288 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -347,7 +347,7 @@ __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
 			.iov_base = &rfc1002_marker,
 			.iov_len  = 4
 		};
-		iov_iter_kvec(&smb_msg.msg_iter, WRITE, &hiov, 1, 4);
+		iov_iter_kvec(&smb_msg.msg_iter, ITER_SOURCE, &hiov, 1, 4);
 		rc = smb_send_kvec(server, &smb_msg, &sent);
 		if (rc < 0)
 			goto unmask;
@@ -368,7 +368,7 @@ __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
 			size += iov[i].iov_len;
 		}
 
-		iov_iter_kvec(&smb_msg.msg_iter, WRITE, iov, n_vec, size);
+		iov_iter_kvec(&smb_msg.msg_iter, ITER_SOURCE, iov, n_vec, size);
 
 		rc = smb_send_kvec(server, &smb_msg, &sent);
 		if (rc < 0)
@@ -384,7 +384,7 @@ __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
 			rqst_page_get_length(&rqst[j], i, &bvec.bv_len,
 					     &bvec.bv_offset);
 
-			iov_iter_bvec(&smb_msg.msg_iter, WRITE,
+			iov_iter_bvec(&smb_msg.msg_iter, ITER_SOURCE,
 				      &bvec, 1, bvec.bv_len);
 			rc = smb_send_kvec(server, &smb_msg, &sent);
 			if (rc < 0)
diff --git a/fs/coredump.c b/fs/coredump.c
index aaf7b362090c..9a745d08c57f 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -857,7 +857,7 @@ static int dump_emit_page(struct coredump_params *cprm, struct page *page)
 	if (dump_interrupted())
 		return 0;
 	pos = file->f_pos;
-	iov_iter_bvec(&iter, WRITE, &bvec, 1, PAGE_SIZE);
+	iov_iter_bvec(&iter, ITER_SOURCE, &bvec, 1, PAGE_SIZE);
 	n = __kernel_write_iter(cprm->file, &iter, &pos);
 	if (n != PAGE_SIZE)
 		return 0;
diff --git a/fs/erofs/fscache.c b/fs/erofs/fscache.c
index af5ed6b9c54d..4c837be3b6e3 100644
--- a/fs/erofs/fscache.c
+++ b/fs/erofs/fscache.c
@@ -194,7 +194,7 @@ static int erofs_fscache_read_folios_async(struct fscache_cookie *cookie,
 
 		atomic_inc(&rreq->nr_outstanding);
 
-		iov_iter_xarray(&iter, READ, &rreq->mapping->i_pages,
+		iov_iter_xarray(&iter, ITER_DEST, &rreq->mapping->i_pages,
 				start + done, subreq->len);
 
 		ret = fscache_read(cres, subreq->start, &iter,
@@ -290,7 +290,7 @@ static int erofs_fscache_data_read(struct address_space *mapping,
 		if (IS_ERR(src))
 			return PTR_ERR(src);
 
-		iov_iter_xarray(&iter, READ, &mapping->i_pages, pos, PAGE_SIZE);
+		iov_iter_xarray(&iter, ITER_DEST, &mapping->i_pages, pos, PAGE_SIZE);
 		if (copy_to_iter(src + offset, size, &iter) != size) {
 			erofs_put_metabuf(&buf);
 			return -EFAULT;
@@ -302,7 +302,7 @@ static int erofs_fscache_data_read(struct address_space *mapping,
 
 	if (!(map.m_flags & EROFS_MAP_MAPPED)) {
 		count = len;
-		iov_iter_xarray(&iter, READ, &mapping->i_pages, pos, count);
+		iov_iter_xarray(&iter, ITER_DEST, &mapping->i_pages, pos, count);
 		iov_iter_zero(count, &iter);
 		return count;
 	}
diff --git a/fs/fscache/io.c b/fs/fscache/io.c
index 3af3b08a9bb3..0d2b8dec8f82 100644
--- a/fs/fscache/io.c
+++ b/fs/fscache/io.c
@@ -286,7 +286,7 @@ void __fscache_write_to_cache(struct fscache_cookie *cookie,
 	 * taken into account.
 	 */
 
-	iov_iter_xarray(&iter, WRITE, &mapping->i_pages, start, len);
+	iov_iter_xarray(&iter, ITER_SOURCE, &mapping->i_pages, start, len);
 	fscache_write(cres, start, &iter, fscache_wreq_done, wreq);
 	return;
 
diff --git a/fs/fuse/ioctl.c b/fs/fuse/ioctl.c
index 61d8afcb10a3..fcce94ace2c2 100644
--- a/fs/fuse/ioctl.c
+++ b/fs/fuse/ioctl.c
@@ -255,7 +255,7 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
 		ap.args.in_pages = true;
 
 		err = -EFAULT;
-		iov_iter_init(&ii, WRITE, in_iov, in_iovs, in_size);
+		iov_iter_init(&ii, ITER_SOURCE, in_iov, in_iovs, in_size);
 		for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= ap.num_pages); i++) {
 			c = copy_page_from_iter(ap.pages[i], 0, PAGE_SIZE, &ii);
 			if (c != PAGE_SIZE && iov_iter_count(&ii))
@@ -324,7 +324,7 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
 		goto out;
 
 	err = -EFAULT;
-	iov_iter_init(&ii, READ, out_iov, out_iovs, transferred);
+	iov_iter_init(&ii, ITER_DEST, out_iov, out_iovs, transferred);
 	for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= ap.num_pages); i++) {
 		c = copy_page_to_iter(ap.pages[i], 0, PAGE_SIZE, &ii);
 		if (c != PAGE_SIZE && iov_iter_count(&ii))
diff --git a/fs/netfs/io.c b/fs/netfs/io.c
index e374767d1b68..7f753380e047 100644
--- a/fs/netfs/io.c
+++ b/fs/netfs/io.c
@@ -23,7 +23,7 @@ static void netfs_clear_unread(struct netfs_io_subrequest *subreq)
 {
 	struct iov_iter iter;
 
-	iov_iter_xarray(&iter, READ, &subreq->rreq->mapping->i_pages,
+	iov_iter_xarray(&iter, ITER_DEST, &subreq->rreq->mapping->i_pages,
 			subreq->start + subreq->transferred,
 			subreq->len   - subreq->transferred);
 	iov_iter_zero(iov_iter_count(&iter), &iter);
@@ -49,7 +49,7 @@ static void netfs_read_from_cache(struct netfs_io_request *rreq,
 	struct iov_iter iter;
 
 	netfs_stat(&netfs_n_rh_read);
-	iov_iter_xarray(&iter, READ, &rreq->mapping->i_pages,
+	iov_iter_xarray(&iter, ITER_DEST, &rreq->mapping->i_pages,
 			subreq->start + subreq->transferred,
 			subreq->len   - subreq->transferred);
 
@@ -208,7 +208,7 @@ static void netfs_rreq_do_write_to_cache(struct netfs_io_request *rreq)
 			continue;
 		}
 
-		iov_iter_xarray(&iter, WRITE, &rreq->mapping->i_pages,
+		iov_iter_xarray(&iter, ITER_SOURCE, &rreq->mapping->i_pages,
 				subreq->start, subreq->len);
 
 		atomic_inc(&rreq->nr_copy_ops);
diff --git a/fs/nfs/fscache.c b/fs/nfs/fscache.c
index e861d7bae305..e731c00a9fcb 100644
--- a/fs/nfs/fscache.c
+++ b/fs/nfs/fscache.c
@@ -252,7 +252,7 @@ static int fscache_fallback_read_page(struct inode *inode, struct page *page)
 	bvec[0].bv_page		= page;
 	bvec[0].bv_offset	= 0;
 	bvec[0].bv_len		= PAGE_SIZE;
-	iov_iter_bvec(&iter, READ, bvec, ARRAY_SIZE(bvec), PAGE_SIZE);
+	iov_iter_bvec(&iter, ITER_DEST, bvec, ARRAY_SIZE(bvec), PAGE_SIZE);
 
 	ret = fscache_begin_read_operation(&cres, cookie);
 	if (ret < 0)
@@ -282,7 +282,7 @@ static int fscache_fallback_write_page(struct inode *inode, struct page *page,
 	bvec[0].bv_page		= page;
 	bvec[0].bv_offset	= 0;
 	bvec[0].bv_len		= PAGE_SIZE;
-	iov_iter_bvec(&iter, WRITE, bvec, ARRAY_SIZE(bvec), PAGE_SIZE);
+	iov_iter_bvec(&iter, ITER_SOURCE, bvec, ARRAY_SIZE(bvec), PAGE_SIZE);
 
 	ret = fscache_begin_write_operation(&cres, cookie);
 	if (ret < 0)
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 849a720ab43f..a996cbda3b88 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -943,7 +943,7 @@ __be32 nfsd_readv(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	ssize_t host_err;
 
 	trace_nfsd_read_vector(rqstp, fhp, offset, *count);
-	iov_iter_kvec(&iter, READ, vec, vlen, *count);
+	iov_iter_kvec(&iter, ITER_DEST, vec, vlen, *count);
 	host_err = vfs_iter_read(file, &iter, &ppos, 0);
 	return nfsd_finish_read(rqstp, fhp, file, offset, count, eof, host_err);
 }
@@ -1033,7 +1033,7 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct nfsd_file *nf,
 	if (stable && !use_wgather)
 		flags |= RWF_SYNC;
 
-	iov_iter_kvec(&iter, WRITE, vec, vlen, *cnt);
+	iov_iter_kvec(&iter, ITER_SOURCE, vec, vlen, *cnt);
 	since = READ_ONCE(file->f_wb_err);
 	if (verf)
 		nfsd_copy_write_verifier(verf, nn);
diff --git a/fs/ocfs2/cluster/tcp.c b/fs/ocfs2/cluster/tcp.c
index 6f5a3fb97c7f..37d222bdfc8c 100644
--- a/fs/ocfs2/cluster/tcp.c
+++ b/fs/ocfs2/cluster/tcp.c
@@ -900,7 +900,7 @@ static int o2net_recv_tcp_msg(struct socket *sock, void *data, size_t len)
 {
 	struct kvec vec = { .iov_len = len, .iov_base = data, };
 	struct msghdr msg = { .msg_flags = MSG_DONTWAIT, };
-	iov_iter_kvec(&msg.msg_iter, READ, &vec, 1, len);
+	iov_iter_kvec(&msg.msg_iter, ITER_DEST, &vec, 1, len);
 	return sock_recvmsg(sock, &msg, MSG_DONTWAIT);
 }
 
diff --git a/fs/orangefs/inode.c b/fs/orangefs/inode.c
index 7a8c0c6e698d..b3bbb5a5787a 100644
--- a/fs/orangefs/inode.c
+++ b/fs/orangefs/inode.c
@@ -53,7 +53,7 @@ static int orangefs_writepage_locked(struct page *page,
 	bv.bv_len = wlen;
 	bv.bv_offset = off % PAGE_SIZE;
 	WARN_ON(wlen == 0);
-	iov_iter_bvec(&iter, WRITE, &bv, 1, wlen);
+	iov_iter_bvec(&iter, ITER_SOURCE, &bv, 1, wlen);
 
 	ret = wait_for_direct_io(ORANGEFS_IO_WRITE, inode, &off, &iter, wlen,
 	    len, wr, NULL, NULL);
@@ -112,7 +112,7 @@ static int orangefs_writepages_work(struct orangefs_writepages *ow,
 		else
 			ow->bv[i].bv_offset = 0;
 	}
-	iov_iter_bvec(&iter, WRITE, ow->bv, ow->npages, ow->len);
+	iov_iter_bvec(&iter, ITER_SOURCE, ow->bv, ow->npages, ow->len);
 
 	WARN_ON(ow->off >= len);
 	if (ow->off + ow->len > len)
@@ -270,7 +270,7 @@ static void orangefs_readahead(struct readahead_control *rac)
 	offset = readahead_pos(rac);
 	i_pages = &rac->mapping->i_pages;
 
-	iov_iter_xarray(&iter, READ, i_pages, offset, readahead_length(rac));
+	iov_iter_xarray(&iter, ITER_DEST, i_pages, offset, readahead_length(rac));
 
 	/* read in the pages. */
 	if ((ret = wait_for_direct_io(ORANGEFS_IO_READ, inode,
@@ -303,7 +303,7 @@ static int orangefs_read_folio(struct file *file, struct folio *folio)
 	bv.bv_page = &folio->page;
 	bv.bv_len = folio_size(folio);
 	bv.bv_offset = 0;
-	iov_iter_bvec(&iter, READ, &bv, 1, folio_size(folio));
+	iov_iter_bvec(&iter, ITER_DEST, &bv, 1, folio_size(folio));
 
 	ret = wait_for_direct_io(ORANGEFS_IO_READ, inode, &off, &iter,
 			folio_size(folio), inode->i_size, NULL, NULL, file);
diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c
index 74747571d58e..09a81e4b1273 100644
--- a/fs/proc/vmcore.c
+++ b/fs/proc/vmcore.c
@@ -199,7 +199,7 @@ ssize_t __weak elfcorehdr_read(char *buf, size_t count, u64 *ppos)
 	struct kvec kvec = { .iov_base = buf, .iov_len = count };
 	struct iov_iter iter;
 
-	iov_iter_kvec(&iter, READ, &kvec, 1, count);
+	iov_iter_kvec(&iter, ITER_DEST, &kvec, 1, count);
 
 	return read_from_oldmem(&iter, count, ppos, false);
 }
@@ -212,7 +212,7 @@ ssize_t __weak elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos)
 	struct kvec kvec = { .iov_base = buf, .iov_len = count };
 	struct iov_iter iter;
 
-	iov_iter_kvec(&iter, READ, &kvec, 1, count);
+	iov_iter_kvec(&iter, ITER_DEST, &kvec, 1, count);
 
 	return read_from_oldmem(&iter, count, ppos,
 			cc_platform_has(CC_ATTR_MEM_ENCRYPT));
@@ -437,7 +437,7 @@ static vm_fault_t mmap_vmcore_fault(struct vm_fault *vmf)
 		offset = (loff_t) index << PAGE_SHIFT;
 		kvec.iov_base = page_address(page);
 		kvec.iov_len = PAGE_SIZE;
-		iov_iter_kvec(&iter, READ, &kvec, 1, PAGE_SIZE);
+		iov_iter_kvec(&iter, ITER_DEST, &kvec, 1, PAGE_SIZE);
 
 		rc = __read_vmcore(&iter, &offset);
 		if (rc < 0) {
diff --git a/fs/read_write.c b/fs/read_write.c
index 24b9668d6377..7a2ff6157eda 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -384,7 +384,7 @@ static ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, lo
 
 	init_sync_kiocb(&kiocb, filp);
 	kiocb.ki_pos = (ppos ? *ppos : 0);
-	iov_iter_ubuf(&iter, READ, buf, len);
+	iov_iter_ubuf(&iter, ITER_DEST, buf, len);
 
 	ret = call_read_iter(filp, &kiocb, &iter);
 	BUG_ON(ret == -EIOCBQUEUED);
@@ -424,7 +424,7 @@ ssize_t __kernel_read(struct file *file, void *buf, size_t count, loff_t *pos)
 
 	init_sync_kiocb(&kiocb, file);
 	kiocb.ki_pos = pos ? *pos : 0;
-	iov_iter_kvec(&iter, READ, &iov, 1, iov.iov_len);
+	iov_iter_kvec(&iter, ITER_DEST, &iov, 1, iov.iov_len);
 	ret = file->f_op->read_iter(&kiocb, &iter);
 	if (ret > 0) {
 		if (pos)
@@ -486,7 +486,7 @@ static ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t
 
 	init_sync_kiocb(&kiocb, filp);
 	kiocb.ki_pos = (ppos ? *ppos : 0);
-	iov_iter_ubuf(&iter, WRITE, (void __user *)buf, len);
+	iov_iter_ubuf(&iter, ITER_SOURCE, (void __user *)buf, len);
 
 	ret = call_write_iter(filp, &kiocb, &iter);
 	BUG_ON(ret == -EIOCBQUEUED);
@@ -533,7 +533,7 @@ ssize_t __kernel_write(struct file *file, const void *buf, size_t count, loff_t
 		.iov_len	= min_t(size_t, count, MAX_RW_COUNT),
 	};
 	struct iov_iter iter;
-	iov_iter_kvec(&iter, WRITE, &iov, 1, iov.iov_len);
+	iov_iter_kvec(&iter, ITER_SOURCE, &iov, 1, iov.iov_len);
 	return __kernel_write_iter(file, &iter, pos);
 }
 /*
@@ -911,7 +911,7 @@ static ssize_t vfs_readv(struct file *file, const struct iovec __user *vec,
 	struct iov_iter iter;
 	ssize_t ret;
 
-	ret = import_iovec(READ, vec, vlen, ARRAY_SIZE(iovstack), &iov, &iter);
+	ret = import_iovec(ITER_DEST, vec, vlen, ARRAY_SIZE(iovstack), &iov, &iter);
 	if (ret >= 0) {
 		ret = do_iter_read(file, &iter, pos, flags);
 		kfree(iov);
@@ -928,7 +928,7 @@ static ssize_t vfs_writev(struct file *file, const struct iovec __user *vec,
 	struct iov_iter iter;
 	ssize_t ret;
 
-	ret = import_iovec(WRITE, vec, vlen, ARRAY_SIZE(iovstack), &iov, &iter);
+	ret = import_iovec(ITER_SOURCE, vec, vlen, ARRAY_SIZE(iovstack), &iov, &iter);
 	if (ret >= 0) {
 		file_start_write(file);
 		ret = do_iter_write(file, &iter, pos, flags);
diff --git a/fs/seq_file.c b/fs/seq_file.c
index 9456a2032224..f5fdaf3b1572 100644
--- a/fs/seq_file.c
+++ b/fs/seq_file.c
@@ -156,7 +156,7 @@ ssize_t seq_read(struct file *file, char __user *buf, size_t size, loff_t *ppos)
 	ssize_t ret;
 
 	init_sync_kiocb(&kiocb, file);
-	iov_iter_init(&iter, READ, &iov, 1, size);
+	iov_iter_init(&iter, ITER_DEST, &iov, 1, size);
 
 	kiocb.ki_pos = *ppos;
 	ret = seq_read_iter(&kiocb, &iter);
diff --git a/fs/splice.c b/fs/splice.c
index 0878b852b355..5969b7a1d353 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -303,7 +303,7 @@ ssize_t generic_file_splice_read(struct file *in, loff_t *ppos,
 	struct kiocb kiocb;
 	int ret;
 
-	iov_iter_pipe(&to, READ, pipe, len);
+	iov_iter_pipe(&to, ITER_DEST, pipe, len);
 	init_sync_kiocb(&kiocb, in);
 	kiocb.ki_pos = *ppos;
 	ret = call_read_iter(in, &kiocb, &to);
@@ -682,7 +682,7 @@ iter_file_splice_write(struct pipe_inode_info *pipe, struct file *out,
 			n++;
 		}
 
-		iov_iter_bvec(&from, WRITE, array, n, sd.total_len - left);
+		iov_iter_bvec(&from, ITER_SOURCE, array, n, sd.total_len - left);
 		ret = vfs_iter_write(out, &from, &sd.pos, 0);
 		if (ret <= 0)
 			break;
@@ -1263,9 +1263,9 @@ static int vmsplice_type(struct fd f, int *type)
 	if (!f.file)
 		return -EBADF;
 	if (f.file->f_mode & FMODE_WRITE) {
-		*type = WRITE;
+		*type = ITER_SOURCE;
 	} else if (f.file->f_mode & FMODE_READ) {
-		*type = READ;
+		*type = ITER_DEST;
 	} else {
 		fdput(f);
 		return -EBADF;
@@ -1314,7 +1314,7 @@ SYSCALL_DEFINE4(vmsplice, int, fd, const struct iovec __user *, uiov,
 
 	if (!iov_iter_count(&iter))
 		error = 0;
-	else if (iov_iter_rw(&iter) == WRITE)
+	else if (type == ITER_SOURCE)
 		error = vmsplice_to_pipe(f.file, &iter, flags);
 	else
 		error = vmsplice_to_user(f.file, &iter, flags);