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Message-ID: <20250129064853.2210753-6-senozhatsky@chromium.org>
Date: Wed, 29 Jan 2025 15:43:51 +0900
From: Sergey Senozhatsky <senozhatsky@...omium.org>
To: Andrew Morton <akpm@...ux-foundation.org>,
Minchan Kim <minchan@...nel.org>,
Johannes Weiner <hannes@...xchg.org>,
Yosry Ahmed <yosry.ahmed@...ux.dev>,
Nhat Pham <nphamcs@...il.com>
Cc: linux-mm@...ck.org,
linux-kernel@...r.kernel.org,
Sergey Senozhatsky <senozhatsky@...omium.org>
Subject: [PATCHv1 5/6] zram: switch to new zsmalloc object mapping API
Use new read/write zsmalloc object API. For cases when RO mapped
object spans two physical pages (requires temp buffer) compression
streams now carry around one extra physical page.
Signed-off-by: Sergey Senozhatsky <senozhatsky@...omium.org>
---
drivers/block/zram/zcomp.c | 4 +++-
drivers/block/zram/zcomp.h | 2 ++
drivers/block/zram/zram_drv.c | 28 ++++++++++------------------
3 files changed, 15 insertions(+), 19 deletions(-)
diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c
index efd5919808d9..675f2a51ad5f 100644
--- a/drivers/block/zram/zcomp.c
+++ b/drivers/block/zram/zcomp.c
@@ -45,6 +45,7 @@ static const struct zcomp_ops *backends[] = {
static void zcomp_strm_free(struct zcomp *comp, struct zcomp_strm *strm)
{
comp->ops->destroy_ctx(&strm->ctx);
+ vfree(strm->local_copy);
vfree(strm->buffer);
kfree(strm);
}
@@ -66,12 +67,13 @@ static struct zcomp_strm *zcomp_strm_alloc(struct zcomp *comp)
return NULL;
}
+ strm->local_copy = vzalloc(PAGE_SIZE);
/*
* allocate 2 pages. 1 for compressed data, plus 1 extra in case if
* compressed data is larger than the original one.
*/
strm->buffer = vzalloc(2 * PAGE_SIZE);
- if (!strm->buffer) {
+ if (!strm->buffer || !strm->local_copy) {
zcomp_strm_free(comp, strm);
return NULL;
}
diff --git a/drivers/block/zram/zcomp.h b/drivers/block/zram/zcomp.h
index 62330829db3f..9683d4aa822d 100644
--- a/drivers/block/zram/zcomp.h
+++ b/drivers/block/zram/zcomp.h
@@ -34,6 +34,8 @@ struct zcomp_strm {
struct list_head entry;
/* compression buffer */
void *buffer;
+ /* local copy of handle memory */
+ void *local_copy;
struct zcomp_ctx ctx;
};
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index ad3e8885b0d2..d73e8374e9cc 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -1562,11 +1562,11 @@ static int read_incompressible_page(struct zram *zram, struct page *page,
void *src, *dst;
handle = zram_get_handle(zram, index);
- src = zs_map_object(zram->mem_pool, handle, ZS_MM_RO);
+ src = zs_obj_read_begin(zram->mem_pool, handle, NULL);
dst = kmap_local_page(page);
copy_page(dst, src);
kunmap_local(dst);
- zs_unmap_object(zram->mem_pool, handle);
+ zs_obj_read_end(zram->mem_pool, handle, src);
return 0;
}
@@ -1584,11 +1584,11 @@ static int read_compressed_page(struct zram *zram, struct page *page, u32 index)
prio = zram_get_priority(zram, index);
zstrm = zcomp_stream_get(zram->comps[prio]);
- src = zs_map_object(zram->mem_pool, handle, ZS_MM_RO);
+ src = zs_obj_read_begin(zram->mem_pool, handle, zstrm->local_copy);
dst = kmap_local_page(page);
ret = zcomp_decompress(zram->comps[prio], zstrm, src, size, dst);
kunmap_local(dst);
- zs_unmap_object(zram->mem_pool, handle);
+ zs_obj_read_end(zram->mem_pool, handle, src);
zcomp_stream_put(zram->comps[prio], zstrm);
return ret;
@@ -1684,7 +1684,7 @@ static int write_incompressible_page(struct zram *zram, struct page *page,
u32 index)
{
unsigned long handle;
- void *src, *dst;
+ void *src;
/*
* This function is called from preemptible context so we don't need
@@ -1701,11 +1701,9 @@ static int write_incompressible_page(struct zram *zram, struct page *page,
return -ENOMEM;
}
- dst = zs_map_object(zram->mem_pool, handle, ZS_MM_WO);
src = kmap_local_page(page);
- memcpy(dst, src, PAGE_SIZE);
+ zs_obj_write(zram->mem_pool, handle, src, PAGE_SIZE);
kunmap_local(src);
- zs_unmap_object(zram->mem_pool, handle);
zram_slot_write_lock(zram, index);
zram_set_flag(zram, index, ZRAM_HUGE);
@@ -1726,7 +1724,7 @@ static int zram_write_page(struct zram *zram, struct page *page, u32 index)
int ret = 0;
unsigned long handle;
unsigned int comp_len;
- void *dst, *mem;
+ void *mem;
struct zcomp_strm *zstrm;
unsigned long element;
bool same_filled;
@@ -1769,11 +1767,8 @@ static int zram_write_page(struct zram *zram, struct page *page, u32 index)
return -ENOMEM;
}
- dst = zs_map_object(zram->mem_pool, handle, ZS_MM_WO);
-
- memcpy(dst, zstrm->buffer, comp_len);
+ zs_obj_write(zram->mem_pool, handle, zstrm->buffer, comp_len);
zcomp_stream_put(zram->comps[ZRAM_PRIMARY_COMP], zstrm);
- zs_unmap_object(zram->mem_pool, handle);
zram_slot_write_lock(zram, index);
zram_set_handle(zram, index, handle);
@@ -1882,7 +1877,7 @@ static int recompress_slot(struct zram *zram, u32 index, struct page *page,
unsigned int class_index_old;
unsigned int class_index_new;
u32 num_recomps = 0;
- void *src, *dst;
+ void *src;
int ret;
handle_old = zram_get_handle(zram, index);
@@ -2020,12 +2015,9 @@ static int recompress_slot(struct zram *zram, u32 index, struct page *page,
return 0;
}
- dst = zs_map_object(zram->mem_pool, handle_new, ZS_MM_WO);
- memcpy(dst, zstrm->buffer, comp_len_new);
+ zs_obj_write(zram->mem_pool, handle_new, zstrm->buffer, comp_len_new);
zcomp_stream_put(zram->comps[prio], zstrm);
- zs_unmap_object(zram->mem_pool, handle_new);
-
zram_free_page(zram, index);
zram_set_handle(zram, index, handle_new);
zram_set_obj_size(zram, index, comp_len_new);
--
2.48.1.262.g85cc9f2d1e-goog
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