diff options
| author | Juergen Gross <jgross@suse.com> | 2022-05-30 10:26:34 +0200 |
|---|---|---|
| committer | Juergen Gross <jgross@suse.com> | 2022-06-01 07:24:17 +0200 |
| commit | 41925b105e345ebc84cedb64f59d20cb14a62613 (patch) | |
| tree | db46827005d233292fc714cc01b80d62edb43d55 /drivers/xen/xenbus | |
| parent | 0a19bab54ef44348aa5edfc2b8ff47f63a45ae15 (diff) | |
| download | linux-41925b105e345ebc84cedb64f59d20cb14a62613.tar.gz | |
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.c | 8 |
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; } |