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Diffstat (limited to 'arch/x86/xen/p2m.c')
-rw-r--r--arch/x86/xen/p2m.c38
1 files changed, 31 insertions, 7 deletions
diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c
index bfc08b13044b..cab9f766bb06 100644
--- a/arch/x86/xen/p2m.c
+++ b/arch/x86/xen/p2m.c
@@ -112,6 +112,15 @@ static unsigned long *p2m_identity;
static pte_t *p2m_missing_pte;
static pte_t *p2m_identity_pte;
+/*
+ * Hint at last populated PFN.
+ *
+ * Used to set HYPERVISOR_shared_info->arch.max_pfn so the toolstack
+ * can avoid scanning the whole P2M (which may be sized to account for
+ * hotplugged memory).
+ */
+static unsigned long xen_p2m_last_pfn;
+
static inline unsigned p2m_top_index(unsigned long pfn)
{
BUG_ON(pfn >= MAX_P2M_PFN);
@@ -270,7 +279,7 @@ void xen_setup_mfn_list_list(void)
else
HYPERVISOR_shared_info->arch.pfn_to_mfn_frame_list_list =
virt_to_mfn(p2m_top_mfn);
- HYPERVISOR_shared_info->arch.max_pfn = xen_max_p2m_pfn;
+ HYPERVISOR_shared_info->arch.max_pfn = xen_p2m_last_pfn;
HYPERVISOR_shared_info->arch.p2m_generation = 0;
HYPERVISOR_shared_info->arch.p2m_vaddr = (unsigned long)xen_p2m_addr;
HYPERVISOR_shared_info->arch.p2m_cr3 =
@@ -406,6 +415,8 @@ void __init xen_vmalloc_p2m_tree(void)
static struct vm_struct vm;
unsigned long p2m_limit;
+ xen_p2m_last_pfn = xen_max_p2m_pfn;
+
p2m_limit = (phys_addr_t)P2M_LIMIT * 1024 * 1024 * 1024 / PAGE_SIZE;
vm.flags = VM_ALLOC;
vm.size = ALIGN(sizeof(unsigned long) * max(xen_max_p2m_pfn, p2m_limit),
@@ -519,7 +530,7 @@ static pte_t *alloc_p2m_pmd(unsigned long addr, pte_t *pte_pg)
* the new pages are installed with cmpxchg; if we lose the race then
* simply free the page we allocated and use the one that's there.
*/
-static bool alloc_p2m(unsigned long pfn)
+int xen_alloc_p2m_entry(unsigned long pfn)
{
unsigned topidx;
unsigned long *top_mfn_p, *mid_mfn;
@@ -529,6 +540,9 @@ static bool alloc_p2m(unsigned long pfn)
unsigned long addr = (unsigned long)(xen_p2m_addr + pfn);
unsigned long p2m_pfn;
+ if (xen_feature(XENFEAT_auto_translated_physmap))
+ return 0;
+
ptep = lookup_address(addr, &level);
BUG_ON(!ptep || level != PG_LEVEL_4K);
pte_pg = (pte_t *)((unsigned long)ptep & ~(PAGE_SIZE - 1));
@@ -537,7 +551,7 @@ static bool alloc_p2m(unsigned long pfn)
/* PMD level is missing, allocate a new one */
ptep = alloc_p2m_pmd(addr, pte_pg);
if (!ptep)
- return false;
+ return -ENOMEM;
}
if (p2m_top_mfn && pfn < MAX_P2M_PFN) {
@@ -555,7 +569,7 @@ static bool alloc_p2m(unsigned long pfn)
mid_mfn = alloc_p2m_page();
if (!mid_mfn)
- return false;
+ return -ENOMEM;
p2m_mid_mfn_init(mid_mfn, p2m_missing);
@@ -581,7 +595,7 @@ static bool alloc_p2m(unsigned long pfn)
p2m = alloc_p2m_page();
if (!p2m)
- return false;
+ return -ENOMEM;
if (p2m_pfn == PFN_DOWN(__pa(p2m_missing)))
p2m_init(p2m);
@@ -608,8 +622,15 @@ static bool alloc_p2m(unsigned long pfn)
free_p2m_page(p2m);
}
- return true;
+ /* Expanded the p2m? */
+ if (pfn > xen_p2m_last_pfn) {
+ xen_p2m_last_pfn = pfn;
+ HYPERVISOR_shared_info->arch.max_pfn = xen_p2m_last_pfn;
+ }
+
+ return 0;
}
+EXPORT_SYMBOL(xen_alloc_p2m_entry);
unsigned long __init set_phys_range_identity(unsigned long pfn_s,
unsigned long pfn_e)
@@ -671,7 +692,10 @@ bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn)
bool set_phys_to_machine(unsigned long pfn, unsigned long mfn)
{
if (unlikely(!__set_phys_to_machine(pfn, mfn))) {
- if (!alloc_p2m(pfn))
+ int ret;
+
+ ret = xen_alloc_p2m_entry(pfn);
+ if (ret < 0)
return false;
return __set_phys_to_machine(pfn, mfn);