[PATCH v3 03/20] mm/zsmalloc: convert __zs_map_object/__zs_unmap_object to use zpdesc

From: alexs
Date: Mon Jul 08 2024 - 02:29:25 EST


From: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>

These two functions take pointer to an array of struct page. Introduce
zpdesc_kmap_atomic() and make __zs_{map,unmap}_object() take pointer
to an array of zpdesc instead of page.

Add silly type casting when calling them. Casting will be removed late.

Signed-off-by: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>
Signed-off-by: Alex Shi (Tencent) <alexs@xxxxxxxxxx>
---
mm/zsmalloc.c | 21 +++++++++++++--------
1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index 243677a9c6d2..68a39c233d34 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -243,6 +243,11 @@ struct zs_pool {
atomic_t compaction_in_progress;
};

+static inline void *zpdesc_kmap_atomic(struct zpdesc *zpdesc)
+{
+ return kmap_atomic(zpdesc_page(zpdesc));
+}
+
struct zspage {
struct {
unsigned int huge:HUGE_BITS;
@@ -1061,7 +1066,7 @@ static inline void __zs_cpu_down(struct mapping_area *area)
}

static void *__zs_map_object(struct mapping_area *area,
- struct page *pages[2], int off, int size)
+ struct zpdesc *zpdescs[2], int off, int size)
{
int sizes[2];
void *addr;
@@ -1078,10 +1083,10 @@ static void *__zs_map_object(struct mapping_area *area,
sizes[1] = size - sizes[0];

/* copy object to per-cpu buffer */
- addr = kmap_atomic(pages[0]);
+ addr = zpdesc_kmap_atomic(zpdescs[0]);
memcpy(buf, addr + off, sizes[0]);
kunmap_atomic(addr);
- addr = kmap_atomic(pages[1]);
+ addr = zpdesc_kmap_atomic(zpdescs[1]);
memcpy(buf + sizes[0], addr, sizes[1]);
kunmap_atomic(addr);
out:
@@ -1089,7 +1094,7 @@ static void *__zs_map_object(struct mapping_area *area,
}

static void __zs_unmap_object(struct mapping_area *area,
- struct page *pages[2], int off, int size)
+ struct zpdesc *zpdescs[2], int off, int size)
{
int sizes[2];
void *addr;
@@ -1108,10 +1113,10 @@ static void __zs_unmap_object(struct mapping_area *area,
sizes[1] = size - sizes[0];

/* copy per-cpu buffer to object */
- addr = kmap_atomic(pages[0]);
+ addr = zpdesc_kmap_atomic(zpdescs[0]);
memcpy(addr + off, buf, sizes[0]);
kunmap_atomic(addr);
- addr = kmap_atomic(pages[1]);
+ addr = zpdesc_kmap_atomic(zpdescs[1]);
memcpy(addr, buf + sizes[0], sizes[1]);
kunmap_atomic(addr);

@@ -1252,7 +1257,7 @@ void *zs_map_object(struct zs_pool *pool, unsigned long handle,
pages[1] = get_next_page(page);
BUG_ON(!pages[1]);

- ret = __zs_map_object(area, pages, off, class->size);
+ ret = __zs_map_object(area, (struct zpdesc **)pages, off, class->size);
out:
if (likely(!ZsHugePage(zspage)))
ret += ZS_HANDLE_SIZE;
@@ -1287,7 +1292,7 @@ void zs_unmap_object(struct zs_pool *pool, unsigned long handle)
pages[1] = get_next_page(page);
BUG_ON(!pages[1]);

- __zs_unmap_object(area, pages, off, class->size);
+ __zs_unmap_object(area, (struct zpdesc **)pages, off, class->size);
}
local_unlock(&zs_map_area.lock);

--
2.43.0