From: Dave Hansen There are a billion ways to refer to a physical memory address. One of the x86 PMD freeing code location chooses to use a 'pte_t *' to point to a PMD page and then call a PTE-specific freeing function for it. That's a bit wonky. Just use a 'struct ptdesc *' instead. Its entire purpose is to refer to page table pages. It also means being able to remove an explicit cast. Right now, pte_free_kernel() is a one-liner that calls pagetable_dtor_free(). Effectively, all this patch does is remove one superfluous __pa(__va(paddr)) conversion and then call pagetable_dtor_free() directly instead of through a helper. Signed-off-by: Dave Hansen Signed-off-by: Lu Baolu Reviewed-by: Jason Gunthorpe Reviewed-by: Kevin Tian --- include/linux/mm.h | 6 ++++-- arch/x86/mm/pgtable.c | 12 ++++++------ 2 files changed, 10 insertions(+), 8 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 15ce0c415d36..94e2ec6c5685 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3203,8 +3203,7 @@ pte_t *pte_offset_map_rw_nolock(struct mm_struct *mm, pmd_t *pmd, ((unlikely(pmd_none(*(pmd))) && __pte_alloc_kernel(pmd))? \ NULL: pte_offset_kernel(pmd, address)) -#if defined(CONFIG_SPLIT_PMD_PTLOCKS) - +#if defined(CONFIG_SPLIT_PMD_PTLOCKS) || defined(CONFIG_X86_64) static inline struct page *pmd_pgtable_page(pmd_t *pmd) { unsigned long mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1); @@ -3215,6 +3214,9 @@ static inline struct ptdesc *pmd_ptdesc(pmd_t *pmd) { return page_ptdesc(pmd_pgtable_page(pmd)); } +#endif + +#if defined(CONFIG_SPLIT_PMD_PTLOCKS) static inline spinlock_t *pmd_lockptr(struct mm_struct *mm, pmd_t *pmd) { diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index ddf248c3ee7d..c830ccbc2fd8 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -729,7 +729,7 @@ int pmd_clear_huge(pmd_t *pmd) int pud_free_pmd_page(pud_t *pud, unsigned long addr) { pmd_t *pmd, *pmd_sv; - pte_t *pte; + struct ptdesc *pt; int i; pmd = pud_pgtable(*pud); @@ -750,8 +750,8 @@ int pud_free_pmd_page(pud_t *pud, unsigned long addr) for (i = 0; i < PTRS_PER_PMD; i++) { if (!pmd_none(pmd_sv[i])) { - pte = (pte_t *)pmd_page_vaddr(pmd_sv[i]); - pte_free_kernel(&init_mm, pte); + pt = pmd_ptdesc(&pmd_sv[i]); + pagetable_dtor_free(pt); } } @@ -772,15 +772,15 @@ int pud_free_pmd_page(pud_t *pud, unsigned long addr) */ int pmd_free_pte_page(pmd_t *pmd, unsigned long addr) { - pte_t *pte; + struct ptdesc *pt; - pte = (pte_t *)pmd_page_vaddr(*pmd); + pt = pmd_ptdesc(pmd); pmd_clear(pmd); /* INVLPG to clear all paging-structure caches */ flush_tlb_kernel_range(addr, addr + PAGE_SIZE-1); - pte_free_kernel(&init_mm, pte); + pagetable_dtor_free(pt); return 1; } -- 2.43.0