From b6ff9345a46af564da32ad480490eaa97840d0b6 Mon Sep 17 00:00:00 2001 From: Elliott Mitchell Date: Tue, 6 Apr 2021 09:59:30 +0200 Subject: [PATCH] xen: create VM_MEMATTR_XEN for Xen memory mappings The requirements for pages shared with Xen/other VMs may vary from architecture to architecture. As such create a macro which various architectures can use. Remove a use of PAT_WRITE_BACK in xenstore.c. This is a x86-ism which shouldn't have been present in a common area. Original idea: Julien Grall , 2014-01-14 06:44:08 Approach suggested by: royger Reviewed by: royger, mhorne Differential Revision: https://reviews.freebsd.org/D29351 --- sys/dev/xen/bus/xenpv.c | 2 +- sys/dev/xen/console/xen_console.c | 2 +- sys/dev/xen/xenstore/xenstore.c | 2 +- sys/x86/include/xen/xen-os.h | 3 +++ 4 files changed, 6 insertions(+), 3 deletions(-) diff --git a/sys/dev/xen/bus/xenpv.c b/sys/dev/xen/bus/xenpv.c index d9db10b7005d..080c82c73f08 100644 --- a/sys/dev/xen/bus/xenpv.c +++ b/sys/dev/xen/bus/xenpv.c @@ -125,7 +125,7 @@ xenpv_alloc_physmem(device_t dev, device_t child, int *res_id, size_t size) phys_addr = rman_get_start(res); error = vm_phys_fictitious_reg_range(phys_addr, phys_addr + size, - VM_MEMATTR_DEFAULT); + VM_MEMATTR_XEN); if (error) { bus_release_resource(child, SYS_RES_MEMORY, *res_id, res); return (NULL); diff --git a/sys/dev/xen/console/xen_console.c b/sys/dev/xen/console/xen_console.c index 7eed30885e6b..8ad755dbf214 100644 --- a/sys/dev/xen/console/xen_console.c +++ b/sys/dev/xen/console/xen_console.c @@ -273,7 +273,7 @@ static void xencons_early_init_ring(struct xencons_priv *cons) { cons->intf = pmap_mapdev_attr(ptoa(xen_get_console_mfn()), PAGE_SIZE, - VM_MEMATTR_WRITE_BACK); + VM_MEMATTR_XEN); cons->evtchn = xen_get_console_evtchn(); } diff --git a/sys/dev/xen/xenstore/xenstore.c b/sys/dev/xen/xenstore/xenstore.c index 890cfe009411..dc00ed0d50b8 100644 --- a/sys/dev/xen/xenstore/xenstore.c +++ b/sys/dev/xen/xenstore/xenstore.c @@ -1130,7 +1130,7 @@ xs_attach(device_t dev) } else { xs.gpfn = xen_get_xenstore_mfn(); xen_store = pmap_mapdev_attr(ptoa(xs.gpfn), PAGE_SIZE, - PAT_WRITE_BACK); + VM_MEMATTR_XEN); xs.initialized = true; } diff --git a/sys/x86/include/xen/xen-os.h b/sys/x86/include/xen/xen-os.h index 86bacadc8521..78d44ad7c9d7 100644 --- a/sys/x86/include/xen/xen-os.h +++ b/sys/x86/include/xen/xen-os.h @@ -30,6 +30,9 @@ #ifndef _MACHINE_X86_XEN_XEN_OS_H_ #define _MACHINE_X86_XEN_XEN_OS_H_ +/* Shared memory needs write-back as its cache attribute for coherency. */ +#define VM_MEMATTR_XEN VM_MEMATTR_WRITE_BACK + /* Everything below this point is not included by assembler (.S) files. */ #ifndef __ASSEMBLY__