linux/drivers/xen/xenbus
Juergen Gross 41925b105e xen: replace xen_remap() with memremap()
xen_remap() is used to establish mappings for frames not under direct
control of the kernel: for Xenstore and console ring pages, and for
grant pages of non-PV guests.

Today xen_remap() is defined to use ioremap() on x86 (doing uncached
mappings), and ioremap_cache() on Arm (doing cached mappings).

Uncached mappings for those use cases are bad for performance, so they
should be avoided if possible. As all use cases of xen_remap() don't
require uncached mappings (the mapped area is always physical RAM),
a mapping using the standard WB cache mode is fine.

As sparse is flagging some of the xen_remap() use cases to be not
appropriate for iomem(), as the result is not annotated with the
__iomem modifier, eliminate xen_remap() completely and replace all
use cases with memremap() specifying the MEMREMAP_WB caching mode.

xen_unmap() can be replaced with memunmap().

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Link: https://lore.kernel.org/r/20220530082634.6339-1-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
2022-06-01 07:24:17 +02:00
..
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
xenbus_client.c xen: switch gnttab_end_foreign_access() to take a struct page pointer 2022-05-27 11:05:29 +02:00
xenbus_comms.c xen: Fix event channel callback via INTX/GSI 2021-01-13 16:12:00 +01:00
xenbus_dev_backend.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
xenbus_dev_frontend.c xen/xenbus: fix self-deadlock after killing user process 2019-10-02 16:40:11 -04:00
xenbus_probe_backend.c xenbus/xenbus_backend: Disallow pending watch messages 2020-12-14 10:08:40 +01:00
xenbus_probe_frontend.c xen: add "not_essential" flag to struct xenbus_driver 2021-11-23 13:41:29 -06:00
xenbus_probe.c xen: replace xen_remap() with memremap() 2022-06-01 07:24:17 +02:00
xenbus_xs.c xen/xenbus: Count pending messages for each watch 2020-12-14 10:07:13 +01:00
xenbus.h bus: Make remove callback return void 2021-07-21 11:53:42 +02:00