2022-09-09 08:52:17

by Alexey Romanov

Subject: [PATCH v1] zsmalloc: use correct types in _first_obj_offset functions

Since commit ffedd09fa9b0
("zsmalloc: Stop using slab fields in struct page") we are using
page->page_type (unsigned int) field instead of page->units (int)
as first object offset in a subpage of zspage. So get_first_obj_offset()
and set_first_obj_offset() functions should work with unsigned int type.

Fixes: ffedd09fa9b0 ("zsmalloc: Stop using slab fields in struct page")
Signed-off-by: Alexey Romanov <[email protected]>
---
mm/zsmalloc.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index 7f833556e059..13c2a28521e8 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -472,12 +472,12 @@ static inline struct page *get_first_page(struct zspage *zspage)
return first_page;
}

-static inline int get_first_obj_offset(struct page *page)
+static inline unsigned int get_first_obj_offset(struct page *page)
{
return page->page_type;
}

-static inline void set_first_obj_offset(struct page *page, int offset)
+static inline void set_first_obj_offset(struct page *page, unsigned int offset)
{
page->page_type = offset;
}
@@ -1592,7 +1592,7 @@ static void zs_object_copy(struct size_class *class, unsigned long dst,
static unsigned long find_alloced_obj(struct size_class *class,
struct page *page, int *obj_idx)
{
- int offset = 0;
+ unsigned int offset;
int index = *obj_idx;
unsigned long handle = 0;
void *addr = kmap_atomic(page);
@@ -1846,7 +1846,7 @@ static int zs_page_migrate(struct page *newpage, struct page *page,
struct zspage *zspage;
struct page *dummy;
void *s_addr, *d_addr, *addr;
- int offset;
+ unsigned int offset;
unsigned long handle;
unsigned long old_obj, new_obj;
unsigned int obj_idx;
--
2.25.1

2022-09-09 08:55:14

by Sergey Senozhatsky

Subject: Re: [PATCH v1] zsmalloc: use correct types in _first_obj_offset functions

On (22/09/09 11:37), Alexey Romanov wrote:
> Since commit ffedd09fa9b0
> ("zsmalloc: Stop using slab fields in struct page") we are using
> page->page_type (unsigned int) field instead of page->units (int)
> as first object offset in a subpage of zspage. So get_first_obj_offset()
> and set_first_obj_offset() functions should work with unsigned int type.
>
> Fixes: ffedd09fa9b0 ("zsmalloc: Stop using slab fields in struct page")
> Signed-off-by: Alexey Romanov <[email protected]>

Reviewed-by: Sergey Senozhatsky <[email protected]>