linux 5.13 compat: bdevops->revalidate_disk() removed (#12122)

Linux kernel commit 0f00b82e5413571ed225ddbccad6882d7ea60bc7 removes the
revalidate_disk() handler from struct block_device_operations. This
caused a regression, and this commit eliminates the call to it and the
assignment in the block_device_operations static handler assignment
code, when configure identifies that the kernel doesn't support that
API handler.

Reviewed-by: Colin Ian King <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Coleman Kane <[email protected]>
Closes #11967
Closes #11977
(cherry picked from commit 48c7b0e)
Signed-off-by: Jonathon Fernyhough <[email protected]>

Co-authored-by: Coleman Kane <[email protected]>

Author: 2 people

config/kernel-block-device-operations.m4

@@ -52,12 +52,44 @@ AC_DEFUN([ZFS_AC_KERNEL_BLOCK_DEVICE_OPERATIONS_RELEASE_VOID], [
 	])
 ])
 
+dnl #
+dnl # 5.13 API change
+dnl # block_device_operations->revalidate_disk() was removed
+dnl #
+AC_DEFUN([ZFS_AC_KERNEL_SRC_BLOCK_DEVICE_OPERATIONS_REVALIDATE_DISK], [
+	ZFS_LINUX_TEST_SRC([block_device_operations_revalidate_disk], [
+		#include <linux/blkdev.h>
+
+		int blk_revalidate_disk(struct gendisk *disk) {
+			return(0);
+		}
+
+		static const struct block_device_operations
+		    bops __attribute__ ((unused)) = {
+			.revalidate_disk	= blk_revalidate_disk,
+		};
+	], [], [$NO_UNUSED_BUT_SET_VARIABLE])
+])
+
+AC_DEFUN([ZFS_AC_KERNEL_BLOCK_DEVICE_OPERATIONS_REVALIDATE_DISK], [
+	AC_MSG_CHECKING([whether bops->revalidate_disk() exists])
+	ZFS_LINUX_TEST_RESULT([block_device_operations_revalidate_disk], [
+		AC_DEFINE([HAVE_BLOCK_DEVICE_OPERATIONS_REVALIDATE_DISK], [1],
+			[Define if revalidate_disk() in block_device_operations])
+		AC_MSG_RESULT(yes)
+	],[
+		AC_MSG_RESULT(no)
+	])
+])
+
 AC_DEFUN([ZFS_AC_KERNEL_SRC_BLOCK_DEVICE_OPERATIONS], [
 	ZFS_AC_KERNEL_SRC_BLOCK_DEVICE_OPERATIONS_CHECK_EVENTS
 	ZFS_AC_KERNEL_SRC_BLOCK_DEVICE_OPERATIONS_RELEASE_VOID
+	ZFS_AC_KERNEL_SRC_BLOCK_DEVICE_OPERATIONS_REVALIDATE_DISK
 ])
 
 AC_DEFUN([ZFS_AC_KERNEL_BLOCK_DEVICE_OPERATIONS], [
 	ZFS_AC_KERNEL_BLOCK_DEVICE_OPERATIONS_CHECK_EVENTS
 	ZFS_AC_KERNEL_BLOCK_DEVICE_OPERATIONS_RELEASE_VOID
+	ZFS_AC_KERNEL_BLOCK_DEVICE_OPERATIONS_REVALIDATE_DISK
 ])

include/os/linux/kernel/linux/blkdev_compat.h

@@ -277,18 +277,22 @@ bio_set_bi_error(struct bio *bio, int error)
 static inline int
 zfs_check_media_change(struct block_device *bdev)
 {
+#ifdef HAVE_BLOCK_DEVICE_OPERATIONS_REVALIDATE_DISK
 	struct gendisk *gd = bdev->bd_disk;
 	const struct block_device_operations *bdo = gd->fops;
+#endif
 
 	if (!bdev_check_media_change(bdev))
 		return (0);
 
+#ifdef HAVE_BLOCK_DEVICE_OPERATIONS_REVALIDATE_DISK
 	/*
 	 * Force revalidation, to mimic the old behavior of
 	 * check_disk_change()
 	 */
 	if (bdo->revalidate_disk)
 		bdo->revalidate_disk(gd);
+#endif
 
 	return (0);
 }

module/os/linux/zfs/zvol_os.c

@@ -721,7 +721,9 @@ static struct block_device_operations zvol_ops = {
 	.ioctl			= zvol_ioctl,
 	.compat_ioctl		= zvol_compat_ioctl,
 	.check_events		= zvol_check_events,
+#ifdef HAVE_BLOCK_DEVICE_OPERATIONS_REVALIDATE_DISK
 	.revalidate_disk	= zvol_revalidate_disk,
+#endif
 	.getgeo			= zvol_getgeo,
 	.owner			= THIS_MODULE,
 #ifdef HAVE_SUBMIT_BIO_IN_BLOCK_DEVICE_OPERATIONS