]> git.baikalelectronics.ru Git - kernel.git/commit
xen-blkfront: Apply 'feature_persistent' parameter when connect
authorSeongJae Park <sj@kernel.org>
Fri, 15 Jul 2022 22:51:08 +0000 (22:51 +0000)
committerJuergen Gross <jgross@suse.com>
Fri, 12 Aug 2022 10:13:54 +0000 (12:13 +0200)
commit805810b39745c4333888530a8c4ff5830ad3053f
tree7c3679ed0b0407e46a0209ec5559c025826d2212
parentd626e33fd447dc9615107d6c3a6316d6ac1f700c
xen-blkfront: Apply 'feature_persistent' parameter when connect

In some use cases[1], the backend is created while the frontend doesn't
support the persistent grants feature, but later the frontend can be
changed to support the feature and reconnect.  In the past, 'blkback'
enabled the persistent grants feature since it unconditionally checked
if frontend supports the persistent grants feature for every connect
('connect_ring()') and decided whether it should use persistent grans or
not.

However, commit 3d14b04b1cc9 ("xen-blkback: add a parameter for
disabling of persistent grants") has mistakenly changed the behavior.
It made the frontend feature support check to not be repeated once it
shown the 'feature_persistent' as 'false', or the frontend doesn't
support persistent grants.

Similar behavioral change has made on 'blkfront' by commit bd2bac1f49a3
("xen-blkfront: add a parameter for disabling of persistent grants").
This commit changes the behavior of the parameter to make effect for
every connect, so that the previous behavior of 'blkfront' can be
restored.

[1] https://lore.kernel.org/xen-devel/CAJwUmVB6H3iTs-C+U=v-pwJB7-_ZRHPxHzKRJZ22xEPW7z8a=g@mail.gmail.com/

Fixes: bd2bac1f49a3 ("xen-blkfront: add a parameter for disabling of persistent grants")
Cc: <stable@vger.kernel.org> # 5.10.x
Signed-off-by: SeongJae Park <sj@kernel.org>
Reviewed-by: Maximilian Heyne <mheyne@amazon.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/20220715225108.193398-4-sj@kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Documentation/ABI/testing/sysfs-driver-xen-blkfront
drivers/block/xen-blkfront.c