[PATCH v4 4/4] powerpc/mm: unstub radix__vmemmap_remove_mapping()
From: Reza Arbab <hidden>
Date: 2017-01-03 20:43:54
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
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 <redacted> --- 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