[PATCH 2/5] mm/vmalloc: Extend __alloc_vmap_area() with extra arguments

From: Uladzislau Rezki (Sony)
Date: Tue Jun 07 2022 - 05:36:01 EST


It implies that __alloc_vmap_area() allocates only from the
global vmap space, therefore a list-head and rb-tree, which
represent a free vmap space, are not passed as parameters to
this function and are accessed directly from this function.

Extend the __alloc_vmap_area() and other dependent functions
to have a possibility to allocate from different trees making
an interface common and not specific.

There is no functional change as a result of this patch.

Signed-off-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
---
mm/vmalloc.c | 30 ++++++++++++++++--------------
1 file changed, 16 insertions(+), 14 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index 0102d6d5fcdf..745e89eb6ca1 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1234,15 +1234,15 @@ is_within_this_va(struct vmap_area *va, unsigned long size,
* overhead.
*/
static __always_inline struct vmap_area *
-find_vmap_lowest_match(unsigned long size, unsigned long align,
- unsigned long vstart, bool adjust_search_size)
+find_vmap_lowest_match(struct rb_root *root, unsigned long size,
+ unsigned long align, unsigned long vstart, bool adjust_search_size)
{
struct vmap_area *va;
struct rb_node *node;
unsigned long length;

/* Start from the root. */
- node = free_vmap_area_root.rb_node;
+ node = root->rb_node;

/* Adjust the search size for alignment overhead. */
length = adjust_search_size ? size + align - 1 : size;
@@ -1370,9 +1370,9 @@ classify_va_fit_type(struct vmap_area *va,
}

static __always_inline int
-adjust_va_to_fit_type(struct vmap_area *va,
- unsigned long nva_start_addr, unsigned long size,
- enum fit_type type)
+adjust_va_to_fit_type(struct rb_root *root, struct list_head *head,
+ struct vmap_area *va, unsigned long nva_start_addr,
+ unsigned long size, enum fit_type type)
{
struct vmap_area *lva = NULL;

@@ -1384,7 +1384,7 @@ adjust_va_to_fit_type(struct vmap_area *va,
* V NVA V
* |---------------|
*/
- unlink_va_augment(va, &free_vmap_area_root);
+ unlink_va_augment(va, root);
kmem_cache_free(vmap_area_cachep, va);
} else if (type == LE_FIT_TYPE) {
/*
@@ -1462,8 +1462,7 @@ adjust_va_to_fit_type(struct vmap_area *va,
augment_tree_propagate_from(va);

if (lva) /* type == NE_FIT_TYPE */
- insert_vmap_area_augment(lva, &va->rb_node,
- &free_vmap_area_root, &free_vmap_area_list);
+ insert_vmap_area_augment(lva, &va->rb_node, root, head);
}

return 0;
@@ -1474,7 +1473,8 @@ adjust_va_to_fit_type(struct vmap_area *va,
* Otherwise a vend is returned that indicates failure.
*/
static __always_inline unsigned long
-__alloc_vmap_area(unsigned long size, unsigned long align,
+__alloc_vmap_area(struct rb_root *root, struct list_head *head,
+ unsigned long size, unsigned long align,
unsigned long vstart, unsigned long vend)
{
bool adjust_search_size = true;
@@ -1495,7 +1495,7 @@ __alloc_vmap_area(unsigned long size, unsigned long align,
if (align <= PAGE_SIZE || (align > PAGE_SIZE && (vend - vstart) == size))
adjust_search_size = false;

- va = find_vmap_lowest_match(size, align, vstart, adjust_search_size);
+ va = find_vmap_lowest_match(root, size, align, vstart, adjust_search_size);
if (unlikely(!va))
return vend;

@@ -1514,7 +1514,7 @@ __alloc_vmap_area(unsigned long size, unsigned long align,
return vend;

/* Update the free vmap_area. */
- ret = adjust_va_to_fit_type(va, nva_start_addr, size, type);
+ ret = adjust_va_to_fit_type(root, head, va, nva_start_addr, size, type);
if (ret)
return vend;

@@ -1605,7 +1605,8 @@ static struct vmap_area *alloc_vmap_area(unsigned long size,

retry:
preload_this_cpu_lock(&free_vmap_area_lock, gfp_mask, node);
- addr = __alloc_vmap_area(size, align, vstart, vend);
+ addr = __alloc_vmap_area(&free_vmap_area_root, &free_vmap_area_list,
+ size, align, vstart, vend);
spin_unlock(&free_vmap_area_lock);

/*
@@ -3886,7 +3887,8 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
/* It is a BUG(), but trigger recovery instead. */
goto recovery;

- ret = adjust_va_to_fit_type(va, start, size, type);
+ ret = adjust_va_to_fit_type(&free_vmap_area_root,
+ &free_vmap_area_list, va, start, size, type);
if (unlikely(ret))
goto recovery;

--
2.30.2