[PATCH v2 54/61] mm/mprotect: Use maple tree navigation instead of vma linked list
From: Liam Howlett <hidden>
Date: 2021-08-17 15:55:29
Also in:
lkml
Subsystem:
memory management, memory mapping, the rest · Maintainers:
Andrew Morton, Liam R. Howlett, Lorenzo Stoakes, Linus Torvalds
From: "Liam R. Howlett" <redacted> Signed-off-by: Liam R. Howlett <redacted> --- mm/mprotect.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/mm/mprotect.c b/mm/mprotect.c
index 883e2cc85cad..a4041d2c0dfb 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c@@ -528,6 +528,7 @@ static int do_mprotect_pkey(unsigned long start, size_t len, const int grows = prot & (PROT_GROWSDOWN|PROT_GROWSUP); const bool rier = (current->personality & READ_IMPLIES_EXEC) && (prot & PROT_READ); + MA_STATE(mas, ¤t->mm->mm_mt, start, start); start = untagged_addr(start);
@@ -559,11 +560,15 @@ 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); + rcu_read_lock(); + vma = mas_find(&mas, ULONG_MAX); error = -ENOMEM; - if (!vma) + if (!vma) { + rcu_read_unlock(); goto out; - prev = vma->vm_prev; + } + prev = mas_prev(&mas, 0); + rcu_read_unlock(); if (unlikely(grows & PROT_GROWSDOWN)) { if (vma->vm_start >= end) goto out;
@@ -644,7 +649,7 @@ static int do_mprotect_pkey(unsigned long start, size_t len, if (nstart >= end) goto out; - vma = prev->vm_next; + vma = vma_next(current->mm, prev); if (!vma || vma->vm_start != nstart) { error = -ENOMEM; goto out;
--
2.30.2