[PATCH v12 58/69] mm/mprotect: use maple tree navigation instead of vma linked list

Liam Howlett
2022-07-20T02:23:13Z

Link: https://lkml.kernel.org/r/20220504011345.662299-43-Liam.Howlett@oracle.com
Link: https://lkml.kernel.org/r/20220621204632.3370049-59-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: SeongJae Park <sj@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
mm/mprotect.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/mm/mprotect.c b/mm/mprotect.c
index ba5592655ee3..27fb652151e4 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -621,6 +621,7 @@ 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);

@@ -652,7 +653,7 @@ 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;
@@ -678,7 +679,7 @@ 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 ; ; ) {
@@ -741,7 +742,7 @@ 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