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authorJuergen Gross <jgross@suse.com>2022-05-30 10:26:34 +0200
committerJuergen Gross <jgross@suse.com>2022-06-01 07:24:17 +0200
commit41925b105e345ebc84cedb64f59d20cb14a62613 (patch)
treedb46827005d233292fc714cc01b80d62edb43d55 /drivers/xen/xenbus
parent0a19bab54ef44348aa5edfc2b8ff47f63a45ae15 (diff)
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>
Diffstat (limited to 'drivers/xen/xenbus')
-rw-r--r--drivers/xen/xenbus/xenbus_probe.c8
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
index d367f2bd2b93..58b732dcbfb8 100644
--- a/drivers/xen/xenbus/xenbus_probe.c
+++ b/drivers/xen/xenbus/xenbus_probe.c
@@ -752,8 +752,8 @@ static void xenbus_probe(void)
xenstored_ready = 1;
if (!xen_store_interface) {
- xen_store_interface = xen_remap(xen_store_gfn << XEN_PAGE_SHIFT,
- XEN_PAGE_SIZE);
+ xen_store_interface = memremap(xen_store_gfn << XEN_PAGE_SHIFT,
+ XEN_PAGE_SIZE, MEMREMAP_WB);
/*
* Now it is safe to free the IRQ used for xenstore late
* initialization. No need to unbind: it is about to be
@@ -1009,8 +1009,8 @@ static int __init xenbus_init(void)
#endif
xen_store_gfn = (unsigned long)v;
xen_store_interface =
- xen_remap(xen_store_gfn << XEN_PAGE_SHIFT,
- XEN_PAGE_SIZE);
+ memremap(xen_store_gfn << XEN_PAGE_SHIFT,
+ XEN_PAGE_SIZE, MEMREMAP_WB);
if (xen_store_interface->connection != XENSTORE_CONNECTED)
wait = true;
}