drbd/0011-compat-block-pass-a-gendisk-to-open.patch

From b993152e80676f5b9ce583c9471b630cbd0675d7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Moritz=20=22WanzenBug=22=20Wanzenb=C3=B6ck?=
 <moritz.wanzenboeck@linbit.com>
Date: Fri, 8 Sep 2023 15:09:47 +0200
Subject: [PATCH 11/20] compat: block: pass a gendisk to ->open

See also upstream Linux kernel commit
d32e2bf83791 ("block: pass a gendisk to ->open")

Original message:

->open is only called on the whole device.  Make that explicit by
passing a gendisk instead of the block_device.
---
 ...ice_operations_open__no_takes_gendisk.cocci | 18 ++++++++++++++++++
 drbd/drbd-kernel-compat/gen_patch_names.c      |  3 +++
 ...lock_device_operations_open_takes_gendisk.c | 17 +++++++++++++++++
 drbd/drbd_main.c                               | 10 +++++-----
 4 files changed, 43 insertions(+), 5 deletions(-)
 create mode 100644 drbd/drbd-kernel-compat/cocci/block_device_operations_open__no_takes_gendisk.cocci
 create mode 100644 drbd/drbd-kernel-compat/tests/block_device_operations_open_takes_gendisk.c

diff --git a/drbd/drbd-kernel-compat/cocci/block_device_operations_open__no_takes_gendisk.cocci b/drbd/drbd-kernel-compat/cocci/block_device_operations_open__no_takes_gendisk.cocci
new file mode 100644
index 000000000000..2ba2856da9db
--- /dev/null
+++ b/drbd/drbd-kernel-compat/cocci/block_device_operations_open__no_takes_gendisk.cocci
@@ -0,0 +1,18 @@
+@ drbd_open_arg @
+identifier gd;
+fresh identifier bdev = "" ## "bdev";
+@@
+  drbd_open(
+- 	struct gendisk *gd,
++ 	struct block_device *bdev,
+  ... ) {
+<...
+(
+- 	gd->part0
++ 	bdev
+|
+- 	gd
++ 	bdev->bd_disk
+)
+...>
+}
diff --git a/drbd/drbd-kernel-compat/gen_patch_names.c b/drbd/drbd-kernel-compat/gen_patch_names.c
index 7071a0a4c5ec..6e4f06d9a3a7 100644
--- a/drbd/drbd-kernel-compat/gen_patch_names.c
+++ b/drbd/drbd-kernel-compat/gen_patch_names.c
@@ -559,6 +559,9 @@ int main(int argc, char **argv)
 	patch(1, "blkdev_get_by_path", true, false,
 	      COMPAT_BLKDEV_GET_BY_PATH_HAS_HOLDER_OPS, "has_holder_ops");
 
+	patch(1, "block_device_operations_open", true, false,
+	      COMPAT_BLOCK_DEVICE_OPERATIONS_OPEN_TAKES_GENDISK, "takes_gendisk");
+
 /* #define BLKDEV_ISSUE_ZEROOUT_EXPORTED */
 /* #define BLKDEV_ZERO_NOUNMAP */
 
diff --git a/drbd/drbd-kernel-compat/tests/block_device_operations_open_takes_gendisk.c b/drbd/drbd-kernel-compat/tests/block_device_operations_open_takes_gendisk.c
new file mode 100644
index 000000000000..d5f20fd569fb
--- /dev/null
+++ b/drbd/drbd-kernel-compat/tests/block_device_operations_open_takes_gendisk.c
@@ -0,0 +1,17 @@
+/* { "version": "v6.5-rc1", "commit": "d32e2bf83791727a84ad5d3e3d713e82f9adbe30", "comment": "block: pass a gendisk to ->open", "author": "Christoph Hellwig <hch@lst.de>", "date": "Thu Jun 8 13:02:36 2023 +0200" } */
+#include <linux/blkdev.h>
+
+#ifndef __same_type
+# define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
+#endif
+
+int foo_open(struct gendisk *disk, unsigned int mode)
+{
+	return 0;
+}
+
+void foo(void)
+{
+	struct block_device_operations ops;
+	BUILD_BUG_ON(!(__same_type(ops.open, &foo_open)));
+}
diff --git a/drbd/drbd_main.c b/drbd/drbd_main.c
index e6ed1185c710..53cb4c9e7db3 100644
--- a/drbd/drbd_main.c
+++ b/drbd/drbd_main.c
@@ -52,7 +52,7 @@
 #include "drbd_meta_data.h"
 #include "drbd_dax_pmem.h"
 
-static int drbd_open(struct block_device *bdev, fmode_t mode);
+static int drbd_open(struct gendisk *gd, fmode_t mode);
 static void drbd_release(struct gendisk *gd, fmode_t mode);
 static void md_sync_timer_fn(struct timer_list *t);
 static int w_bitmap_io(struct drbd_work *w, int unused);
@@ -2646,9 +2646,9 @@ out:
 	spin_unlock(&device->openers_lock);
 }
 
-static int drbd_open(struct block_device *bdev, fmode_t mode)
+static int drbd_open(struct gendisk *gd, fmode_t mode)
 {
-	struct drbd_device *device = bdev->bd_disk->private_data;
+	struct drbd_device *device = gd->private_data;
 	struct drbd_resource *resource = device->resource;
 	long timeout = resource->res_opts.auto_promote_timeout * HZ / 10;
 	enum ioc_rv r;
@@ -2664,7 +2664,7 @@ static int drbd_open(struct block_device *bdev, fmode_t mode)
 
 	/* Fail read-write open early,
 	 * in case someone explicitly set us read-only (blockdev --setro) */
-	if (bdev_read_only(bdev) && (mode & FMODE_WRITE))
+	if (bdev_read_only(gd->part0) && (mode & FMODE_WRITE))
 		return -EACCES;
 
 	if (resource->fail_io[NOW])
@@ -2740,7 +2740,7 @@ out:
 
 	mutex_unlock(&resource->open_release);
 	if (err) {
-		drbd_release(bdev->bd_disk, mode);
+		drbd_release(gd, mode);
 		if (err == -EAGAIN && !(mode & FMODE_NDELAY))
 			err = -EMEDIUMTYPE;
 	}
-- 
2.35.3