[PATCH v4 4/4] powerpc/mm: unstub radix__vmemmap_remove_mapping()
Reza Arbab
arbab at linux.vnet.ibm.com
Wed Jan 4 07:43:38 AEDT 2017
Use remove_pagetable() and friends for radix vmemmap removal.
We do not require the special-case handling of vmemmap done in the x86
versions of these functions. This is because vmemmap_free() has already
freed the mapped pages, and calls us with an aligned address range.
So, add a few failsafe WARNs, but otherwise the code to remove physical
mappings is already sufficient for vmemmap.
Signed-off-by: Reza Arbab <arbab at linux.vnet.ibm.com>
---
arch/powerpc/mm/pgtable-radix.c | 29 ++++++++++++++++++++++++++++-
1 file changed, 28 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c
index f7a8e625..bada0d9 100644
--- a/arch/powerpc/mm/pgtable-radix.c
+++ b/arch/powerpc/mm/pgtable-radix.c
@@ -517,6 +517,15 @@ static void remove_pte_table(pte_t *pte_start, unsigned long addr,
if (!pte_present(*pte))
continue;
+ if (!PAGE_ALIGNED(addr) || !PAGE_ALIGNED(next)) {
+ /*
+ * The vmemmap_free() and remove_section_mapping()
+ * codepaths call us with aligned addresses.
+ */
+ WARN_ONCE(1, "%s: unaligned range\n", __func__);
+ continue;
+ }
+
pte_clear(&init_mm, addr, pte);
}
}
@@ -536,6 +545,12 @@ static void remove_pmd_table(pmd_t *pmd_start, unsigned long addr,
continue;
if (pmd_huge(*pmd)) {
+ if (!IS_ALIGNED(addr, PMD_SIZE) ||
+ !IS_ALIGNED(next, PMD_SIZE)) {
+ WARN_ONCE(1, "%s: unaligned range\n", __func__);
+ continue;
+ }
+
pte_clear(&init_mm, addr, (pte_t *)pmd);
continue;
}
@@ -561,6 +576,12 @@ static void remove_pud_table(pud_t *pud_start, unsigned long addr,
continue;
if (pud_huge(*pud)) {
+ if (!IS_ALIGNED(addr, PUD_SIZE) ||
+ !IS_ALIGNED(next, PUD_SIZE)) {
+ WARN_ONCE(1, "%s: unaligned range\n", __func__);
+ continue;
+ }
+
pte_clear(&init_mm, addr, (pte_t *)pud);
continue;
}
@@ -587,6 +608,12 @@ static void remove_pagetable(unsigned long start, unsigned long end)
continue;
if (pgd_huge(*pgd)) {
+ if (!IS_ALIGNED(addr, PGDIR_SIZE) ||
+ !IS_ALIGNED(next, PGDIR_SIZE)) {
+ WARN_ONCE(1, "%s: unaligned range\n", __func__);
+ continue;
+ }
+
pte_clear(&init_mm, addr, (pte_t *)pgd);
continue;
}
@@ -627,7 +654,7 @@ int __meminit radix__vmemmap_create_mapping(unsigned long start,
#ifdef CONFIG_MEMORY_HOTPLUG
void radix__vmemmap_remove_mapping(unsigned long start, unsigned long page_size)
{
- /* FIXME!! intel does more. We should free page tables mapping vmemmap ? */
+ remove_pagetable(start, start + page_size);
}
#endif
#endif
--
1.8.3.1
More information about the Linuxppc-dev
mailing list