mm/debug_vm_pgtable: drop protection_map[] usage

Patch series "mm: protection_map[] cleanups".


This patch (of 2):

Although protection_map[] contains the platform defined page protection
map for a given vm_flags combination, vm_get_page_prot() is the right
interface to use.  This will also reduce dependency on protection_map[]
which is going to be dropped off completely later on.

Link: https://lkml.kernel.org/r/20220404031840.588321-1-anshuman.khandual@arm.com
Link: https://lkml.kernel.org/r/20220404031840.588321-2-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Anshuman Khandual 2022-04-28 23:16:12 -07:00 committed by akpm
parent b191c9bc33
commit 31d17076b0

View file

@ -93,7 +93,7 @@ struct pgtable_debug_args {
static void __init pte_basic_tests(struct pgtable_debug_args *args, int idx)
{
pgprot_t prot = protection_map[idx];
pgprot_t prot = vm_get_page_prot(idx);
pte_t pte = pfn_pte(args->fixed_pte_pfn, prot);
unsigned long val = idx, *ptr = &val;
@ -101,7 +101,7 @@ static void __init pte_basic_tests(struct pgtable_debug_args *args, int idx)
/*
* This test needs to be executed after the given page table entry
* is created with pfn_pte() to make sure that protection_map[idx]
* is created with pfn_pte() to make sure that vm_get_page_prot(idx)
* does not have the dirty bit enabled from the beginning. This is
* important for platforms like arm64 where (!PTE_RDONLY) indicate
* dirty bit being set.
@ -190,7 +190,7 @@ static void __init pte_savedwrite_tests(struct pgtable_debug_args *args)
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
static void __init pmd_basic_tests(struct pgtable_debug_args *args, int idx)
{
pgprot_t prot = protection_map[idx];
pgprot_t prot = vm_get_page_prot(idx);
unsigned long val = idx, *ptr = &val;
pmd_t pmd;
@ -202,7 +202,7 @@ static void __init pmd_basic_tests(struct pgtable_debug_args *args, int idx)
/*
* This test needs to be executed after the given page table entry
* is created with pfn_pmd() to make sure that protection_map[idx]
* is created with pfn_pmd() to make sure that vm_get_page_prot(idx)
* does not have the dirty bit enabled from the beginning. This is
* important for platforms like arm64 where (!PTE_RDONLY) indicate
* dirty bit being set.
@ -325,7 +325,7 @@ static void __init pmd_savedwrite_tests(struct pgtable_debug_args *args)
#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx)
{
pgprot_t prot = protection_map[idx];
pgprot_t prot = vm_get_page_prot(idx);
unsigned long val = idx, *ptr = &val;
pud_t pud;
@ -337,7 +337,7 @@ static void __init pud_basic_tests(struct pgtable_debug_args *args, int idx)
/*
* This test needs to be executed after the given page table entry
* is created with pfn_pud() to make sure that protection_map[idx]
* is created with pfn_pud() to make sure that vm_get_page_prot(idx)
* does not have the dirty bit enabled from the beginning. This is
* important for platforms like arm64 where (!PTE_RDONLY) indicate
* dirty bit being set.
@ -1106,14 +1106,14 @@ static int __init init_args(struct pgtable_debug_args *args)
/*
* Initialize the debugging data.
*
* protection_map[0] (or even protection_map[8]) will help create
* page table entries with PROT_NONE permission as required for
* pxx_protnone_tests().
* vm_get_page_prot(VM_NONE) or vm_get_page_prot(VM_SHARED|VM_NONE)
* will help create page table entries with PROT_NONE permission as
* required for pxx_protnone_tests().
*/
memset(args, 0, sizeof(*args));
args->vaddr = get_random_vaddr();
args->page_prot = vm_get_page_prot(VMFLAGS);
args->page_prot_none = protection_map[0];
args->page_prot_none = vm_get_page_prot(VM_NONE);
args->is_contiguous_page = false;
args->pud_pfn = ULONG_MAX;
args->pmd_pfn = ULONG_MAX;
@ -1248,12 +1248,19 @@ static int __init debug_vm_pgtable(void)
return ret;
/*
* Iterate over the protection_map[] to make sure that all
* Iterate over each possible vm_flags to make sure that all
* the basic page table transformation validations just hold
* true irrespective of the starting protection value for a
* given page table entry.
*
* Protection based vm_flags combinatins are always linear
* and increasing i.e starting from VM_NONE and going upto
* (VM_SHARED | READ | WRITE | EXEC).
*/
for (idx = 0; idx < ARRAY_SIZE(protection_map); idx++) {
#define VM_FLAGS_START (VM_NONE)
#define VM_FLAGS_END (VM_SHARED | VM_EXEC | VM_WRITE | VM_READ)
for (idx = VM_FLAGS_START; idx <= VM_FLAGS_END; idx++) {
pte_basic_tests(&args, idx);
pmd_basic_tests(&args, idx);
pud_basic_tests(&args, idx);