# HG changeset patch
# User Keir Fraser <keir@xxxxxxx>
# Date 1292586670 0
# Node ID 534a09877cac29c0faf184b765c8c0e53da40331
# Parent f2dba7ff082833775f51c73ec9470b2921caec2d
x86 ept: Define and use atomic_{read,write}_ept_entry().
Signed-off-by: Keir Fraser <keir@xxxxxxx>
Signed-off-by: Tim Deegan <Tim.Deegan@xxxxxxxxxx>
---
xen/arch/x86/mm/hap/p2m-ept.c | 36 ++++++++++++++++++++----------------
1 files changed, 20 insertions(+), 16 deletions(-)
diff -r f2dba7ff0828 -r 534a09877cac xen/arch/x86/mm/hap/p2m-ept.c
--- a/xen/arch/x86/mm/hap/p2m-ept.c Fri Dec 17 10:46:43 2010 +0000
+++ b/xen/arch/x86/mm/hap/p2m-ept.c Fri Dec 17 11:51:10 2010 +0000
@@ -31,6 +31,11 @@
#include <asm/hvm/cacheattr.h>
#include <xen/keyhandler.h>
#include <xen/softirq.h>
+
+#define atomic_read_ept_entry(__pepte) \
+ ( (ept_entry_t) { .epte = atomic_read64(&(__pepte)->epte) } )
+#define atomic_write_ept_entry(__pepte, __epte) \
+ atomic_write64(&(__pepte)->epte, (__epte).epte)
#define is_epte_present(ept_entry) ((ept_entry)->epte & 0x7)
#define is_epte_superpage(ept_entry) ((ept_entry)->sp)
@@ -222,7 +227,7 @@ static int ept_next_level(struct p2m_dom
/* ept_next_level() is called (sometimes) without a lock. Read
* the entry once, and act on the "cached" entry after that to
* avoid races. */
- e=*ept_entry;
+ e = atomic_read_ept_entry(ept_entry);
if ( !is_epte_present(&e) )
{
@@ -235,7 +240,7 @@ static int ept_next_level(struct p2m_dom
if ( !ept_set_middle_entry(p2m, ept_entry) )
return GUEST_TABLE_MAP_FAILED;
else
- e=*ept_entry; /* Refresh */
+ e = atomic_read_ept_entry(ept_entry); /* Refresh */
}
/* The only time sp would be set here is if we had hit a superpage */
@@ -317,6 +322,7 @@ ept_set_entry(struct p2m_domain *p2m, un
if ( i == target )
{
/* We reached the target level. */
+ ept_entry_t new_entry = { .epte = 0 };
/* No need to flush if the old entry wasn't valid */
if ( !is_epte_present(ept_entry) )
@@ -325,8 +331,6 @@ ept_set_entry(struct p2m_domain *p2m, un
if ( mfn_valid(mfn_x(mfn)) || direct_mmio || p2m_is_paged(p2mt) ||
(p2mt == p2m_ram_paging_in_start) )
{
- ept_entry_t new_entry = { .epte = 0 };
-
/* Construct the new entry, and then write it once */
new_entry.emt = epte_get_entry_emt(p2m->domain, gfn, mfn, &ipat,
direct_mmio);
@@ -341,11 +345,9 @@ ept_set_entry(struct p2m_domain *p2m, un
new_entry.mfn = mfn_x(mfn);
ept_p2m_type_to_flags(&new_entry, p2mt);
-
- ept_entry->epte = new_entry.epte;
- }
- else
- ept_entry->epte = 0;
+ }
+
+ atomic_write_ept_entry(ept_entry, new_entry);
}
else
{
@@ -355,7 +357,7 @@ ept_set_entry(struct p2m_domain *p2m, un
ASSERT(is_epte_superpage(ept_entry));
- split_ept_entry = *ept_entry;
+ split_ept_entry = atomic_read_ept_entry(ept_entry);
if ( !ept_split_super_page(p2m, &split_ept_entry, i, target) )
{
@@ -365,7 +367,7 @@ ept_set_entry(struct p2m_domain *p2m, un
/* now install the newly split ept sub-tree */
/* NB: please make sure domian is paused and no in-fly VT-d DMA. */
- *ept_entry = split_ept_entry;
+ atomic_write_ept_entry(ept_entry, split_ept_entry);
/* then move to the level we want to make real changes */
for ( ; i > target; i-- )
@@ -391,7 +393,7 @@ ept_set_entry(struct p2m_domain *p2m, un
ept_p2m_type_to_flags(&new_entry, p2mt);
- ept_entry->epte = new_entry.epte;
+ atomic_write_ept_entry(ept_entry, new_entry);
}
/* Track the highest gfn for which we have ever had a valid mapping */
@@ -711,7 +713,7 @@ static void ept_change_entry_type_page(m
static void ept_change_entry_type_page(mfn_t ept_page_mfn, int ept_page_level,
p2m_type_t ot, p2m_type_t nt)
{
- ept_entry_t *epte = map_domain_page(mfn_x(ept_page_mfn));
+ ept_entry_t e, *epte = map_domain_page(mfn_x(ept_page_mfn));
for ( int i = 0; i < EPT_PAGETABLE_ENTRIES; i++ )
{
@@ -723,11 +725,13 @@ static void ept_change_entry_type_page(m
ept_page_level - 1, ot, nt);
else
{
- if ( epte[i].sa_p2mt != ot )
+ e = atomic_read_ept_entry(&epte[i]);
+ if ( e.sa_p2mt != ot )
continue;
- epte[i].sa_p2mt = nt;
- ept_p2m_type_to_flags(epte + i, nt);
+ e.sa_p2mt = nt;
+ ept_p2m_type_to_flags(&e, nt);
+ atomic_write_ept_entry(&epte[i], e);
}
}
_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog
|
Home