From: Liam R. Howlett <Liam.Howlett@Oracle.com>
Date: Fri, 24 Jul 2020 15:38:39 +0000 (-0400)
Subject: mm/mmap: Change find_vma() to use the maple tree
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=1197b6a554ee4e4678fcfa6e01a88c5358093c9c;p=users%2Fjedix%2Flinux-maple.git

mm/mmap: Change find_vma() to use the maple tree

Start using the maple tree to find VMA entries in an mm_struct.

Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
---

diff --git a/mm/mmap.c b/mm/mmap.c
index 004703cc4e14..a313bfc9fae9 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2564,7 +2564,7 @@ get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
 EXPORT_SYMBOL(get_unmapped_area);
 
 /**
- * mt_find_vma() - Find the VMA for a given address, or the next vma.  May return
+ * find_vma() - Find the VMA for a given address, or the next vma.  May return
  * NULL in the case of no vma at addr or above
  * @mm The mm_struct to check
  * @addr: The address
@@ -2572,7 +2572,7 @@ EXPORT_SYMBOL(get_unmapped_area);
  * Returns: The VMA assoicated with addr, or the next vma.
  * May return NULL in the case of no vma at addr or above.
  */
-struct vm_area_struct *mt_find_vma(struct mm_struct *mm, unsigned long addr)
+struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr)
 {
 	struct vm_area_struct *vma;
 
@@ -2582,55 +2582,11 @@ struct vm_area_struct *mt_find_vma(struct mm_struct *mm, unsigned long addr)
 		return vma;
 
 	vma = mt_find(&mm->mm_mt, &addr, ULONG_MAX);
-
 	if (vma)
 		vmacache_update(addr, vma);
-	return vma;
-}
-
-/* Look up the first VMA which satisfies  addr < vm_end,  NULL if none. */
-struct vm_area_struct *rb_find_vma(struct mm_struct *mm, unsigned long addr)
-{
-	struct rb_node *rb_node;
-	struct vm_area_struct *vma;
 
-	/* Check the cache first. */
-	vma = vmacache_find(mm, addr);
-	if (likely(vma))
-		return vma;
-
-	rb_node = mm->mm_rb.rb_node;
-
-	while (rb_node) {
-		struct vm_area_struct *tmp;
-
-		tmp = rb_entry(rb_node, struct vm_area_struct, vm_rb);
-
-		if (tmp->vm_end > addr) {
-			vma = tmp;
-			if (tmp->vm_start <= addr)
-				break;
-			rb_node = rb_node->rb_left;
-		} else
-			rb_node = rb_node->rb_right;
-	}
-
-	if (vma)
-		vmacache_update(addr, vma);
 	return vma;
 }
-struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr)
-{
-	struct vm_area_struct *ret = rb_find_vma(mm, addr);
-	struct vm_area_struct *mt_ret = mt_find_vma(mm, addr);
-	if (ret != mt_ret) {
-		pr_err("Looking for %lu\n", addr);
-		mt_dump(&mm->mm_mt);
-		pr_err("%px %lu: ret %px mt_ret %px\n", mm, addr, ret, mt_ret);
-	}
-	VM_BUG_ON_VMA((unsigned long)ret != (unsigned long)mt_ret , ret);
-	return ret;
-}
 EXPORT_SYMBOL(find_vma);
 
 /**