[PATCH v6 07/12] mm/debug_vm_pgtable: Use struct pgtable_debug_args in PTE modifying tests
From: Gavin Shan
Date: Mon Aug 09 2021 - 05:28:06 EST
This uses struct pgtable_debug_args in PTE modifying tests. The allocated
page is used as set_pte_at() is used there. The tests are skipped if
the allocated page doesn't exist. It's notable that args->ptep need to be
mapped before the tests. The reason why we don't map args->ptep at the
beginning is PTE entry is only mapped and accessible in atomic context
when CONFIG_HIGHPTE is enabled. So we avoid to do that so that atomic
context is only enabled if needed.
Besides, the unused variable @pte_aligned and @ptep in debug_vm_pgtable()
are dropped.
Signed-off-by: Gavin Shan <gshan@xxxxxxxxxx>
Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
mm/debug_vm_pgtable.c | 67 +++++++++++++++++++++----------------------
1 file changed, 32 insertions(+), 35 deletions(-)
diff --git a/mm/debug_vm_pgtable.c b/mm/debug_vm_pgtable.c
index 6df86555b191..652f26f5ecd6 100644
--- a/mm/debug_vm_pgtable.c
+++ b/mm/debug_vm_pgtable.c
@@ -117,10 +117,7 @@ static void __init pte_basic_tests(struct pgtable_debug_args *args, int idx)
WARN_ON(!pte_dirty(pte_wrprotect(pte_mkdirty(pte))));
}
-static void __init pte_advanced_tests(struct mm_struct *mm,
- struct vm_area_struct *vma, pte_t *ptep,
- unsigned long pfn, unsigned long vaddr,
- pgprot_t prot)
+static void __init pte_advanced_tests(struct pgtable_debug_args *args)
{
pte_t pte;
@@ -129,35 +126,37 @@ static void __init pte_advanced_tests(struct mm_struct *mm,
* This requires set_pte_at to be not used to update an
* existing pte entry. Clear pte before we do set_pte_at
*/
+ if (args->pte_pfn == ULONG_MAX)
+ return;
pr_debug("Validating PTE advanced\n");
- pte = pfn_pte(pfn, prot);
- set_pte_at(mm, vaddr, ptep, pte);
- ptep_set_wrprotect(mm, vaddr, ptep);
- pte = ptep_get(ptep);
+ pte = pfn_pte(args->pte_pfn, args->page_prot);
+ set_pte_at(args->mm, args->vaddr, args->ptep, pte);
+ ptep_set_wrprotect(args->mm, args->vaddr, args->ptep);
+ pte = ptep_get(args->ptep);
WARN_ON(pte_write(pte));
- ptep_get_and_clear(mm, vaddr, ptep);
- pte = ptep_get(ptep);
+ ptep_get_and_clear(args->mm, args->vaddr, args->ptep);
+ pte = ptep_get(args->ptep);
WARN_ON(!pte_none(pte));
- pte = pfn_pte(pfn, prot);
+ pte = pfn_pte(args->pte_pfn, args->page_prot);
pte = pte_wrprotect(pte);
pte = pte_mkclean(pte);
- set_pte_at(mm, vaddr, ptep, pte);
+ set_pte_at(args->mm, args->vaddr, args->ptep, pte);
pte = pte_mkwrite(pte);
pte = pte_mkdirty(pte);
- ptep_set_access_flags(vma, vaddr, ptep, pte, 1);
- pte = ptep_get(ptep);
+ ptep_set_access_flags(args->vma, args->vaddr, args->ptep, pte, 1);
+ pte = ptep_get(args->ptep);
WARN_ON(!(pte_write(pte) && pte_dirty(pte)));
- ptep_get_and_clear_full(mm, vaddr, ptep, 1);
- pte = ptep_get(ptep);
+ ptep_get_and_clear_full(args->mm, args->vaddr, args->ptep, 1);
+ pte = ptep_get(args->ptep);
WARN_ON(!pte_none(pte));
- pte = pfn_pte(pfn, prot);
+ pte = pfn_pte(args->pte_pfn, args->page_prot);
pte = pte_mkyoung(pte);
- set_pte_at(mm, vaddr, ptep, pte);
- ptep_test_and_clear_young(vma, vaddr, ptep);
- pte = ptep_get(ptep);
+ set_pte_at(args->mm, args->vaddr, args->ptep, pte);
+ ptep_test_and_clear_young(args->vma, args->vaddr, args->ptep);
+ pte = ptep_get(args->ptep);
WARN_ON(pte_young(pte));
}
@@ -618,20 +617,21 @@ static void __init pgd_populate_tests(struct mm_struct *mm, pgd_t *pgdp,
}
#endif /* PAGETABLE_P4D_FOLDED */
-static void __init pte_clear_tests(struct mm_struct *mm, pte_t *ptep,
- unsigned long pfn, unsigned long vaddr,
- pgprot_t prot)
+static void __init pte_clear_tests(struct pgtable_debug_args *args)
{
- pte_t pte = pfn_pte(pfn, prot);
+ pte_t pte = pfn_pte(args->pte_pfn, args->page_prot);
+
+ if (args->pte_pfn == ULONG_MAX)
+ return;
pr_debug("Validating PTE clear\n");
#ifndef CONFIG_RISCV
pte = __pte(pte_val(pte) | RANDOM_ORVALUE);
#endif
- set_pte_at(mm, vaddr, ptep, pte);
+ set_pte_at(args->mm, args->vaddr, args->ptep, pte);
barrier();
- pte_clear(mm, vaddr, ptep);
- pte = ptep_get(ptep);
+ pte_clear(args->mm, args->vaddr, args->ptep);
+ pte = ptep_get(args->ptep);
WARN_ON(!pte_none(pte));
}
@@ -1221,11 +1221,10 @@ static int __init debug_vm_pgtable(void)
p4d_t *p4dp, *saved_p4dp;
pud_t *pudp, *saved_pudp;
pmd_t *pmdp, *saved_pmdp, pmd;
- pte_t *ptep;
pgtable_t saved_ptep;
pgprot_t prot;
phys_addr_t paddr;
- unsigned long vaddr, pte_aligned, pmd_aligned;
+ unsigned long vaddr, pmd_aligned;
unsigned long pud_aligned;
spinlock_t *ptl = NULL;
int idx, ret;
@@ -1260,10 +1259,8 @@ static int __init debug_vm_pgtable(void)
*/
paddr = __pa_symbol(&start_kernel);
- pte_aligned = (paddr & PAGE_MASK) >> PAGE_SHIFT;
pmd_aligned = (paddr & PMD_MASK) >> PAGE_SHIFT;
pud_aligned = (paddr & PUD_MASK) >> PAGE_SHIFT;
- WARN_ON(!pfn_valid(pte_aligned));
pgdp = pgd_offset(mm, vaddr);
p4dp = p4d_alloc(mm, pgdp, vaddr);
@@ -1345,10 +1342,10 @@ static int __init debug_vm_pgtable(void)
* proper page table lock.
*/
- ptep = pte_offset_map_lock(mm, pmdp, vaddr, &ptl);
- pte_clear_tests(mm, ptep, pte_aligned, vaddr, prot);
- pte_advanced_tests(mm, vma, ptep, pte_aligned, vaddr, prot);
- pte_unmap_unlock(ptep, ptl);
+ args.ptep = pte_offset_map_lock(args.mm, args.pmdp, args.vaddr, &ptl);
+ pte_clear_tests(&args);
+ pte_advanced_tests(&args);
+ pte_unmap_unlock(args.ptep, ptl);
ptl = pmd_lock(mm, pmdp);
pmd_clear_tests(mm, pmdp);
--
2.23.0