xen/mmu: some early pagetable cleanups
1. make sure early-allocated ptes are pinned, so they can be later
unpinned
2. don't pin pmd+pud, just make them RO
3. scatter some __inits around
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 6e58acd..4db24e1 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -1019,7 +1019,7 @@
return 0;
}
-void __init xen_mark_init_mm_pinned(void)
+static void __init xen_mark_init_mm_pinned(void)
{
xen_pgd_walk(&init_mm, xen_mark_pinned, FIXADDR_TOP);
}
@@ -1470,6 +1470,15 @@
}
#endif
+static void pin_pagetable_pfn(unsigned cmd, unsigned long pfn)
+{
+ struct mmuext_op op;
+ op.cmd = cmd;
+ op.arg1.mfn = pfn_to_mfn(pfn);
+ if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF))
+ BUG();
+}
+
/* Early in boot, while setting up the initial pagetable, assume
everything is pinned. */
static __init void xen_alloc_pte_init(struct mm_struct *mm, unsigned long pfn)
@@ -1478,22 +1487,29 @@
BUG_ON(mem_map); /* should only be used early */
#endif
make_lowmem_page_readonly(__va(PFN_PHYS(pfn)));
+ pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE, pfn);
+}
+
+/* Used for pmd and pud */
+static __init void xen_alloc_pmd_init(struct mm_struct *mm, unsigned long pfn)
+{
+#ifdef CONFIG_FLATMEM
+ BUG_ON(mem_map); /* should only be used early */
+#endif
+ make_lowmem_page_readonly(__va(PFN_PHYS(pfn)));
}
/* Early release_pte assumes that all pts are pinned, since there's
only init_mm and anything attached to that is pinned. */
-static void xen_release_pte_init(unsigned long pfn)
+static __init void xen_release_pte_init(unsigned long pfn)
{
+ pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, pfn);
make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
}
-static void pin_pagetable_pfn(unsigned cmd, unsigned long pfn)
+static __init void xen_release_pmd_init(unsigned long pfn)
{
- struct mmuext_op op;
- op.cmd = cmd;
- op.arg1.mfn = pfn_to_mfn(pfn);
- if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF))
- BUG();
+ make_lowmem_page_readwrite(__va(PFN_PHYS(pfn)));
}
/* This needs to make sure the new pte page is pinned iff its being
@@ -1874,9 +1890,9 @@
.alloc_pte = xen_alloc_pte_init,
.release_pte = xen_release_pte_init,
- .alloc_pmd = xen_alloc_pte_init,
+ .alloc_pmd = xen_alloc_pmd_init,
.alloc_pmd_clone = paravirt_nop,
- .release_pmd = xen_release_pte_init,
+ .release_pmd = xen_release_pmd_init,
#ifdef CONFIG_HIGHPTE
.kmap_atomic_pte = xen_kmap_atomic_pte,
@@ -1914,8 +1930,8 @@
.make_pud = PV_CALLEE_SAVE(xen_make_pud),
.set_pgd = xen_set_pgd_hyper,
- .alloc_pud = xen_alloc_pte_init,
- .release_pud = xen_release_pte_init,
+ .alloc_pud = xen_alloc_pmd_init,
+ .release_pud = xen_release_pmd_init,
#endif /* PAGETABLE_LEVELS == 4 */
.activate_mm = xen_activate_mm,