powerpc/mm: Rename find_linux_pte_or_hugepte()
Add newer helpers to make the function usage simpler. It is always
recommended to use find_current_mm_pte() for walking the page table.
If we cannot use find_current_mm_pte(), it should be documented why
the said usage of __find_linux_pte() is safe against a parallel THP
split.
For now we have KVM code using __find_linux_pte(). This is because kvm
code ends up calling __find_linux_pte() in real mode with MSR_EE=0 but
with PACA soft_enabled = 1. We may want to fix that later and make
sure we keep the MSR_EE and PACA soft_enabled in sync. When we do that
we can switch kvm to use find_linux_pte().
Signed-off-by: Aneesh Kumar K.V <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
index 584c74c..fedb013 100644
--- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c
+++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
@@ -22,6 +22,7 @@
#include <asm/hvcall.h>
#include <asm/synch.h>
#include <asm/ppc-opcode.h>
+#include <asm/pte-walk.h>
/* Translate address of a vmalloc'd thing to a linear map address */
static void *real_vmalloc_addr(void *x)
@@ -31,9 +32,9 @@ static void *real_vmalloc_addr(void *x)
/*
* assume we don't have huge pages in vmalloc space...
* So don't worry about THP collapse/split. Called
- * Only in realmode, hence won't need irq_save/restore.
+ * Only in realmode with MSR_EE = 0, hence won't need irq_save/restore.
*/
- p = __find_linux_pte_or_hugepte(swapper_pg_dir, addr, NULL, NULL);
+ p = find_init_mm_pte(addr, NULL);
if (!p || !pte_present(*p))
return NULL;
addr = (pte_pfn(*p) << PAGE_SHIFT) | (addr & ~PAGE_MASK);
@@ -230,14 +231,13 @@ long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags,
* If we had a page table table change after lookup, we would
* retry via mmu_notifier_retry.
*/
- if (realmode)
- ptep = __find_linux_pte_or_hugepte(pgdir, hva, NULL,
- &hpage_shift);
- else {
+ if (!realmode)
local_irq_save(irq_flags);
- ptep = find_linux_pte_or_hugepte(pgdir, hva, NULL,
- &hpage_shift);
- }
+ /*
+ * If called in real mode we have MSR_EE = 0. Otherwise
+ * we disable irq above.
+ */
+ ptep = __find_linux_pte(pgdir, hva, NULL, &hpage_shift);
if (ptep) {
pte_t pte;
unsigned int host_pte_size;
