[PATCH v8 59/70] mm/mprotect: use maple tree navigation instead of vma linked list

From: Liam Howlett
Date: Tue Apr 26 2022 - 11:11:49 EST


From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>

Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
---
mm/mprotect.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/mm/mprotect.c b/mm/mprotect.c
index 20a46f21cca8..fbb248caf8aa 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -550,6 +550,7 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
const bool rier = (current->personality & READ_IMPLIES_EXEC) &&
(prot & PROT_READ);
struct mmu_gather tlb;
+ MA_STATE(mas, &current->mm->mm_mt, start, start);

start = untagged_addr(start);

@@ -581,7 +582,7 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
if ((pkey != -1) && !mm_pkey_is_allocated(current->mm, pkey))
goto out;

- vma = find_vma(current->mm, start);
+ vma = mas_find(&mas, ULONG_MAX);
error = -ENOMEM;
if (!vma)
goto out;
@@ -607,7 +608,7 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
if (start > vma->vm_start)
prev = vma;
else
- prev = vma->vm_prev;
+ prev = mas_prev(&mas, 0);

tlb_gather_mmu(&tlb, current->mm);
for (nstart = start ; ; ) {
@@ -670,7 +671,7 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
if (nstart >= end)
break;

- vma = prev->vm_next;
+ vma = find_vma(current->mm, prev->vm_end);
if (!vma || vma->vm_start != nstart) {
error = -ENOMEM;
break;
--
2.35.1