git: 33c17670afdb - main - amd64: add pmap_page_set_memattr_noflush()

The branch main has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=33c17670afdb008097858d2fff8d4c4a47d68158

commit 33c17670afdb008097858d2fff8d4c4a47d68158
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2021-10-05 14:12:05 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2021-10-06 02:53:12 +0000

    amd64: add pmap_page_set_memattr_noflush()
    
    Similar to pmap_page_set_memattr() by setting MD page cache attribute
    to the argument.  Unlike pmap_page_set_memattr(), does not flush cache
    for the direct mapping of the page.
    
    Reviewed by:    alc, markj
    Sponsored by:   The FreeBSD Foundation
    MFC after:      1 week
    Differential revision:  https://reviews.freebsd.org/D32318
---
 sys/amd64/amd64/pmap.c   | 17 +++++++++++++++++
 sys/amd64/include/pmap.h |  1 +
 2 files changed, 18 insertions(+)

diff --git a/sys/amd64/amd64/pmap.c b/sys/amd64/amd64/pmap.c
index aae35c5d7e07..f1ddbe548c0f 100644
--- a/sys/amd64/amd64/pmap.c
+++ b/sys/amd64/amd64/pmap.c
@@ -9379,6 +9379,23 @@ pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma)
 		panic("memory attribute change on the direct map failed");
 }
 
+void
+pmap_page_set_memattr_noflush(vm_page_t m, vm_memattr_t ma)
+{
+	int error;
+
+	m->md.pat_mode = ma;
+
+	if ((m->flags & PG_FICTITIOUS) != 0)
+		return;
+	PMAP_LOCK(kernel_pmap);
+	error = pmap_change_props_locked(PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m)),
+	    PAGE_SIZE, PROT_NONE, m->md.pat_mode, 0);
+	PMAP_UNLOCK(kernel_pmap);
+	if (error != 0)
+		panic("memory attribute change on the direct map failed");
+}
+
 /*
  * Changes the specified virtual address range's memory type to that given by
  * the parameter "mode".  The specified virtual address range must be
diff --git a/sys/amd64/include/pmap.h b/sys/amd64/include/pmap.h
index b65668b60023..bd6a8c006813 100644
--- a/sys/amd64/include/pmap.h
+++ b/sys/amd64/include/pmap.h
@@ -499,6 +499,7 @@ void	*pmap_mapdev_pciecfg(vm_paddr_t pa, vm_size_t size);
 bool	pmap_not_in_di(void);
 boolean_t pmap_page_is_mapped(vm_page_t m);
 void	pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma);
+void	pmap_page_set_memattr_noflush(vm_page_t m, vm_memattr_t ma);
 void	pmap_pinit_pml4(vm_page_t);
 void	pmap_pinit_pml5(vm_page_t);
 bool	pmap_ps_enabled(pmap_t pmap);