mm/mprotect: use maple tree navigation instead of vma linked list

Link: https://lkml.kernel.org/r/20220404143501.2016403-60-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/mprotect.c b/mm/mprotect.c
index 20a46f21cca8403fefcc666d591dc3c758a8b7fe..fbb248caf8aa0682e5f18152f3e870b2f423502a 100644 (file)
--- 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;