2023-11-28 08:52:14

by Sergey Senozhatsky

Subject: [PATCH] zram: Use kmap_local_page()

Use kmap_local_page() instead of kmap_atomic() which has been
deprecated.

Signed-off-by: Sergey Senozhatsky <[email protected]>
---
drivers/block/zram/zram_drv.c | 30 +++++++++++++++---------------
1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index f6b286e7f310..2b1d82473be8 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -1321,9 +1321,9 @@ static int zram_read_from_zspool(struct zram *zram, struct page *page,
void *mem;

value = handle ? zram_get_element(zram, index) : 0;
- mem = kmap_atomic(page);
+ mem = kmap_local_page(page);
zram_fill_page(mem, PAGE_SIZE, value);
- kunmap_atomic(mem);
+ kunmap_local(mem);
return 0;
}

@@ -1336,14 +1336,14 @@ static int zram_read_from_zspool(struct zram *zram, struct page *page,

src = zs_map_object(zram->mem_pool, handle, ZS_MM_RO);
if (size == PAGE_SIZE) {
- dst = kmap_atomic(page);
+ dst = kmap_local_page(page);
memcpy(dst, src, PAGE_SIZE);
- kunmap_atomic(dst);
+ kunmap_local(dst);
ret = 0;
} else {
- dst = kmap_atomic(page);
+ dst = kmap_local_page(page);
ret = zcomp_decompress(zstrm, src, size, dst);
- kunmap_atomic(dst);
+ kunmap_local(dst);
zcomp_stream_put(zram->comps[prio]);
}
zs_unmap_object(zram->mem_pool, handle);
@@ -1416,21 +1416,21 @@ static int zram_write_page(struct zram *zram, struct page *page, u32 index)
unsigned long element = 0;
enum zram_pageflags flags = 0;

- mem = kmap_atomic(page);
+ mem = kmap_local_page(page);
if (page_same_filled(mem, &element)) {
- kunmap_atomic(mem);
+ kunmap_local(mem);
/* Free memory associated with this sector now. */
flags = ZRAM_SAME;
atomic64_inc(&zram->stats.same_pages);
goto out;
}
- kunmap_atomic(mem);
+ kunmap_local(mem);

compress_again:
zstrm = zcomp_stream_get(zram->comps[ZRAM_PRIMARY_COMP]);
- src = kmap_atomic(page);
+ src = kmap_local_page(page);
ret = zcomp_compress(zstrm, src, &comp_len);
- kunmap_atomic(src);
+ kunmap_local(src);

if (unlikely(ret)) {
zcomp_stream_put(zram->comps[ZRAM_PRIMARY_COMP]);
@@ -1494,10 +1494,10 @@ static int zram_write_page(struct zram *zram, struct page *page, u32 index)

src = zstrm->buffer;
if (comp_len == PAGE_SIZE)
- src = kmap_atomic(page);
+ src = kmap_local_page(page);
memcpy(dst, src, comp_len);
if (comp_len == PAGE_SIZE)
- kunmap_atomic(src);
+ kunmap_local(src);

zcomp_stream_put(zram->comps[ZRAM_PRIMARY_COMP]);
zs_unmap_object(zram->mem_pool, handle);
@@ -1614,9 +1614,9 @@ static int zram_recompress(struct zram *zram, u32 index, struct page *page,

num_recomps++;
zstrm = zcomp_stream_get(zram->comps[prio]);
- src = kmap_atomic(page);
+ src = kmap_local_page(page);
ret = zcomp_compress(zstrm, src, &comp_len_new);
- kunmap_atomic(src);
+ kunmap_local(src);

if (ret) {
zcomp_stream_put(zram->comps[prio]);
--
2.43.0.rc1.413.gea7ed67945-goog

2023-11-29 00:01:57

by Minchan Kim

Subject: Re: [PATCH] zram: Use kmap_local_page()

On Tue, Nov 28, 2023 at 05:22:07PM +0900, Sergey Senozhatsky wrote:
> Use kmap_local_page() instead of kmap_atomic() which has been
> deprecated.
>
> Signed-off-by: Sergey Senozhatsky <[email protected]>
Acked-by: Minchan Kim <[email protected]>

I didn't know that the kmap_atomic was deprecated.

Thanks.

2023-11-29 04:19:45

by Sergey Senozhatsky

Subject: Re: [PATCH] zram: Use kmap_local_page()

On (23/11/28 16:01), Minchan Kim wrote:
> On Tue, Nov 28, 2023 at 05:22:07PM +0900, Sergey Senozhatsky wrote:
> > Use kmap_local_page() instead of kmap_atomic() which has been
> > deprecated.
> >
> > Signed-off-by: Sergey Senozhatsky <[email protected]>
> Acked-by: Minchan Kim <[email protected]>

Thanks.

> I didn't know that the kmap_atomic was deprecated.

Me neither, figured it out recently (via checkpatch warning).
https://lore.kernel.org/all/[email protected]/

We need to take a look at zsmalloc, the conversion can be a little more
difficult than zram's.