[PATCH 4.19 183/271] Revert "bcache: set CACHE_SET_IO_DISABLE in bch_cached_dev_error()"

From: Greg Kroah-Hartman
Date: Thu Jul 25 2019 - 11:02:18 EST

From: Coly Li <colyli@xxxxxxx>

commit 695277f16b3a102fcc22c97fdf2de77c7b19f0b3 upstream.

This reverts commit 6147305c73e4511ca1a975b766b97a779d442567.

Although this patch helps the failed bcache device to stop faster when
too many I/O errors detected on corresponding cached device, setting
CACHE_SET_IO_DISABLE bit to cache set c->flags was not a good idea. This
operation will disable all I/Os on cache set, which means other attached
bcache devices won't work neither.

Without this patch, the failed bcache device can also be stopped
eventually if internal I/O accomplished (e.g. writeback). Therefore here
I revert it.

Fixes: 6147305c73e4 ("bcache: set CACHE_SET_IO_DISABLE in bch_cached_dev_error()")
Reported-by: Yong Li <mr.liyong@xxxxxx>
Signed-off-by: Coly Li <colyli@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

drivers/md/bcache/super.c | 17 -----------------
1 file changed, 17 deletions(-)

--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1423,8 +1423,6 @@ int bch_flash_dev_create(struct cache_se

bool bch_cached_dev_error(struct cached_dev *dc)
- struct cache_set *c;
if (!dc || test_bit(BCACHE_DEV_CLOSING, &dc->disk.flags))
return false;

@@ -1435,21 +1433,6 @@ bool bch_cached_dev_error(struct cached_
pr_err("stop %s: too many IO errors on backing device %s\n",
dc->disk.disk->disk_name, dc->backing_dev_name);

- /*
- * If the cached device is still attached to a cache set,
- * even dc->io_disable is true and no more I/O requests
- * accepted, cache device internal I/O (writeback scan or
- * garbage collection) may still prevent bcache device from
- * being stopped. So here CACHE_SET_IO_DISABLE should be
- * set to c->flags too, to make the internal I/O to cache
- * device rejected and stopped immediately.
- * If c is NULL, that means the bcache device is not attached
- * to any cache set, then no CACHE_SET_IO_DISABLE bit to set.
- */
- c = dc->disk.c;
- if (c && test_and_set_bit(CACHE_SET_IO_DISABLE, &c->flags))
- pr_info("CACHE_SET_IO_DISABLE already set");
return true;