Fix for DVD reading (rhbz 1781762)

3 files changed, 136 insertions, 0 deletions

diff --git a/0001-bdev-Factor-out-bdev-revalidation-into-a-common-help.patch b/0001-bdev-Factor-out-bdev-revalidation-into-a-common-help.patch
new file mode 100644
index 000000000..1e979a1fa
--- /dev/null
+++ b/0001-bdev-Factor-out-bdev-revalidation-into-a-common-help.patch
@@ -0,0 +1,68 @@
+From aea39223667868c77936546004b84716a623a438 Mon Sep 17 00:00:00 2001
+From: Jan Kara <jack@suse.cz>
+Date: Mon, 21 Oct 2019 10:37:59 +0200
+Subject: [PATCH 1/2] bdev: Factor out bdev revalidation into a common helper
+
+Factor out code handling revalidation of bdev on disk change into a
+common helper.
+
+Signed-off-by: Jan Kara <jack@suse.cz>
+Signed-off-by: Jens Axboe <axboe@kernel.dk>
+---
+ fs/block_dev.c | 26 ++++++++++++++------------
+ 1 file changed, 14 insertions(+), 12 deletions(-)
+
+diff --git a/fs/block_dev.c b/fs/block_dev.c
+index 9c073dbdc1b0..88c6d35ec71d 100644
+--- a/fs/block_dev.c
++++ b/fs/block_dev.c
+@@ -1512,6 +1512,14 @@ EXPORT_SYMBOL(bd_set_size);
+ 
+ static void __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part);
+ 
++static void bdev_disk_changed(struct block_device *bdev, bool invalidate)
++{
++	if (invalidate)
++		invalidate_partitions(bdev->bd_disk, bdev);
++	else
++		rescan_partitions(bdev->bd_disk, bdev);
++}
++
+ /*
+  * bd_mutex locking:
+  *
+@@ -1594,12 +1602,9 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
+ 			 * The latter is necessary to prevent ghost
+ 			 * partitions on a removed medium.
+ 			 */
+-			if (bdev->bd_invalidated) {
+-				if (!ret)
+-					rescan_partitions(disk, bdev);
+-				else if (ret == -ENOMEDIUM)
+-					invalidate_partitions(disk, bdev);
+-			}
++			if (bdev->bd_invalidated &&
++			    (!ret || ret == -ENOMEDIUM))
++				bdev_disk_changed(bdev, ret == -ENOMEDIUM);
+ 
+ 			if (ret)
+ 				goto out_clear;
+@@ -1632,12 +1637,9 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
+ 			if (bdev->bd_disk->fops->open)
+ 				ret = bdev->bd_disk->fops->open(bdev, mode);
+ 			/* the same as first opener case, read comment there */
+-			if (bdev->bd_invalidated) {
+-				if (!ret)
+-					rescan_partitions(bdev->bd_disk, bdev);
+-				else if (ret == -ENOMEDIUM)
+-					invalidate_partitions(bdev->bd_disk, bdev);
+-			}
++			if (bdev->bd_invalidated &&
++			    (!ret || ret == -ENOMEDIUM))
++				bdev_disk_changed(bdev, ret == -ENOMEDIUM);
+ 			if (ret)
+ 				goto out_unlock_bdev;
+ 		}
+-- 
+2.21.0
+
diff --git a/0002-bdev-Refresh-bdev-size-for-disks-without-partitionin.patch b/0002-bdev-Refresh-bdev-size-for-disks-without-partitionin.patch
new file mode 100644
index 000000000..c988fa6a8
--- /dev/null
+++ b/0002-bdev-Refresh-bdev-size-for-disks-without-partitionin.patch
@@ -0,0 +1,61 @@
+From 91ee136f5e2179a0994985ea043468bbbcd400d4 Mon Sep 17 00:00:00 2001
+From: Jan Kara <jack@suse.cz>
+Date: Mon, 21 Oct 2019 10:38:00 +0200
+Subject: [PATCH 2/2] bdev: Refresh bdev size for disks without partitioning
+
+Currently, block device size in not updated on second and further open
+for block devices where partition scan is disabled. This is particularly
+annoying for example for DVD drives as that means block device size does
+not get updated once the media is inserted into a drive if the device is
+already open when inserting the media. This is actually always the case
+for example when pktcdvd is in use.
+
+Fix the problem by revalidating block device size on every open even for
+devices with partition scan disabled.
+
+Signed-off-by: Jan Kara <jack@suse.cz>
+Signed-off-by: Jens Axboe <axboe@kernel.dk>
+---
+ fs/block_dev.c | 19 ++++++++++---------
+ 1 file changed, 10 insertions(+), 9 deletions(-)
+
+diff --git a/fs/block_dev.c b/fs/block_dev.c
+index 88c6d35ec71d..d612468ee66b 100644
+--- a/fs/block_dev.c
++++ b/fs/block_dev.c
+@@ -1403,11 +1403,7 @@ static void flush_disk(struct block_device *bdev, bool kill_dirty)
+ 		       "resized disk %s\n",
+ 		       bdev->bd_disk ? bdev->bd_disk->disk_name : "");
+ 	}
+-
+-	if (!bdev->bd_disk)
+-		return;
+-	if (disk_part_scan_enabled(bdev->bd_disk))
+-		bdev->bd_invalidated = 1;
++	bdev->bd_invalidated = 1;
+ }
+ 
+ /**
+@@ -1514,10 +1510,15 @@ static void __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part);
+ 
+ static void bdev_disk_changed(struct block_device *bdev, bool invalidate)
+ {
+-	if (invalidate)
+-		invalidate_partitions(bdev->bd_disk, bdev);
+-	else
+-		rescan_partitions(bdev->bd_disk, bdev);
++	if (disk_part_scan_enabled(bdev->bd_disk)) {
++		if (invalidate)
++			invalidate_partitions(bdev->bd_disk, bdev);
++		else
++			rescan_partitions(bdev->bd_disk, bdev);
++	} else {
++		check_disk_size_change(bdev->bd_disk, bdev, !invalidate);
++		bdev->bd_invalidated = 0;
++	}
+ }
+ 
+ /*
+-- 
+2.21.0
+
diff --git a/kernel.spec b/kernel.spec
index 7f2c50817..052b0fa6c 100644
--- a/kernel.spec
+++ b/kernel.spec
@@ -866,6 +866,10 @@ Patch535: 0001-libertas-fix-a-potential-NULL-pointer-dereference.patch
 # rhbz 1769600
 Patch536: powerpc-xive-skip-ioremap-of-ESB-pages-for-LSI-interrupts.patch
 
+# rhbz 1781762
+Patch537: 0001-bdev-Factor-out-bdev-revalidation-into-a-common-help.patch
+Patch538: 0002-bdev-Refresh-bdev-size-for-disks-without-partitionin.patch
+
 # END OF PATCH DEFINITIONS
 
 %endif
@@ -2567,6 +2571,9 @@ fi
 #
 #
 %changelog
+* Tue Dec 10 2019 Laura Abbott <labbott@redhat.com>
+- Fix for DVD reading (rhbz 1781762)
+
 * Wed Dec 04 2019 Jeremy Cline <jcline@redhat.com> - 5.4.2-300
 - Linux v5.4.2