From: Liam R. Howlett <Liam.Howlett@oracle.com>
Date: Fri, 16 Jun 2023 15:36:55 +0000 (-0400)
Subject: move find_extend_vma() to memory.c
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=a2344e393900b4844d40bac482d99245b2f9bc92;p=users%2Fjedix%2Flinux-maple.git

move find_extend_vma() to memory.c

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

diff --git a/mm/memory.c b/mm/memory.c
index cb35e52bbd1e..44d10fa417be 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -5367,6 +5367,80 @@ struct vm_area_struct *lock_mm_and_find_vma(struct mm_struct *mm,
 }
 #endif
 
+#ifdef CONFIG_STACK_GROWSUP
+struct vm_area_struct *find_extend_vma_locked(struct mm_struct *mm,
+		unsigned long addr, bool write_locked)
+{
+	struct vm_area_struct *vma, *prev;
+	int err;
+
+	addr &= PAGE_MASK;
+	vma = find_vma_prev(mm, addr, &prev);
+	if (vma && (vma->vm_start <= addr))
+		return vma;
+	if (!prev)
+		return NULL;
+	if (write_locked) {
+		err = expand_stack(prev, addr, true);
+	} else {
+		mmap_read_unlock(mm);
+		mmap_write_lock(mm);
+		vma = find_vma_prev(mm, addr, &prev);
+		if (vma && (vma->vm_start <= addr)) {
+			mmap_write_downgrade(mm);
+			return vma;
+		}
+		if (prev)
+			err = expand_stack(prev, addr, true);
+		mmap_write_downgrade(mm);
+	}
+	if (err)
+		return NULL;
+	if (prev->vm_flags & VM_LOCKED)
+		populate_vma_page_range(prev, addr, prev->vm_end, NULL);
+	return prev;
+}
+#else
+struct vm_area_struct *find_extend_vma_locked(struct mm_struct *mm,
+		unsigned long addr, bool write_locked)
+{
+	struct vm_area_struct *vma;
+	unsigned long start;
+	int err;
+
+	addr &= PAGE_MASK;
+	vma = find_vma(mm, addr);
+	if (!vma)
+		return NULL;
+	if (vma->vm_start <= addr)
+		return vma;
+	start = vma->vm_start;
+	err = expand_stack(vma, addr, write_locked);
+	if (unlikely(err)) {
+		if (err != -EAGAIN)
+			return NULL;
+		if (!upgrade_mmap_lock_carefully(mm, NULL))
+			return NULL;
+		vma = find_vma(mm, addr);
+		if (!vma || expand_stack(vma, addr, true)) {
+			mmap_write_downgrade(mm);
+			return NULL;
+		}
+		mmap_write_downgrade(mm);
+	}
+	if (vma->vm_flags & VM_LOCKED)
+		populate_vma_page_range(vma, addr, start, NULL);
+	return vma;
+}
+#endif
+
+struct vm_area_struct *find_extend_vma(struct mm_struct *mm,
+		unsigned long addr)
+{
+	return find_extend_vma_locked(mm, addr, false);
+}
+EXPORT_SYMBOL_GPL(find_extend_vma);
+
 #ifdef CONFIG_PER_VMA_LOCK
 /*
  * Lookup and lock a VMA under RCU protection. Returned VMA is guaranteed to be
diff --git a/mm/mmap.c b/mm/mmap.c
index 11d6af071c4d..c7c5e0928d48 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2137,38 +2137,6 @@ int expand_stack(struct vm_area_struct *vma, unsigned long address,
 	return expand_upwards(vma, address, write_locked);
 }
 
-struct vm_area_struct *find_extend_vma_locked(struct mm_struct *mm,
-		unsigned long addr, bool write_locked)
-{
-	struct vm_area_struct *vma, *prev;
-	int err;
-
-	addr &= PAGE_MASK;
-	vma = find_vma_prev(mm, addr, &prev);
-	if (vma && (vma->vm_start <= addr))
-		return vma;
-	if (!prev)
-		return NULL;
-	if (write_locked) {
-		err = expand_stack(prev, addr, true);
-	} else {
-		mmap_read_unlock(mm);
-		mmap_write_lock(mm);
-		vma = find_vma_prev(mm, addr, &prev);
-		if (vma && (vma->vm_start <= addr)) {
-			mmap_write_downgrade(mm);
-			return vma;
-		}
-		if (prev)
-			err = expand_stack(prev, addr, true);
-		mmap_write_downgrade(mm);
-	}
-	if (err)
-		return NULL;
-	if (prev->vm_flags & VM_LOCKED)
-		populate_vma_page_range(prev, addr, prev->vm_end, NULL);
-	return prev;
-}
 #else
 int expand_stack(struct vm_area_struct *vma, unsigned long address,
 		bool write_locked)
@@ -2177,47 +2145,8 @@ int expand_stack(struct vm_area_struct *vma, unsigned long address,
 		return -EINVAL;
 	return expand_downwards(vma, address, write_locked);
 }
-
-struct vm_area_struct *find_extend_vma_locked(struct mm_struct *mm,
-		unsigned long addr, bool write_locked)
-{
-	struct vm_area_struct *vma;
-	unsigned long start;
-	int err;
-
-	addr &= PAGE_MASK;
-	vma = find_vma(mm, addr);
-	if (!vma)
-		return NULL;
-	if (vma->vm_start <= addr)
-		return vma;
-	start = vma->vm_start;
-	err = expand_stack(vma, addr, write_locked);
-	if (unlikely(err)) {
-		if (err != -EAGAIN)
-			return NULL;
-		if (!upgrade_mmap_lock_carefully(mm, NULL))
-			return NULL;
-		vma = find_vma(mm, addr);
-		if (!vma || expand_stack(vma, addr, true)) {
-			mmap_write_downgrade(mm);
-			return NULL;
-		}
-		mmap_write_downgrade(mm);
-	}
-	if (vma->vm_flags & VM_LOCKED)
-		populate_vma_page_range(vma, addr, start, NULL);
-	return vma;
-}
 #endif
 
-struct vm_area_struct *find_extend_vma(struct mm_struct *mm,
-		unsigned long addr)
-{
-	return find_extend_vma_locked(mm, addr, false);
-}
-EXPORT_SYMBOL_GPL(find_extend_vma);
-
 /*
  * Ok - we have the memory areas we should free on a maple tree so release them,
  * and do the vma updates.