Add struct zs_ops with a evict() callback function. Add documentation to zs_free() function clarifying that it cannot be called with a zs_pool handle after that handle has been successfully evicted; since evict calls into a function provided by the zs_pool creator, the creator is therefore responsible for ensuring this requirement.
This is required to implement zsmalloc shrinking. Signed-off-by: Dan Streetman <[email protected]> Cc: Minchan Kim <[email protected]> --- drivers/block/zram/zram_drv.c | 2 +- include/linux/zsmalloc.h | 6 +++++- mm/zsmalloc.c | 26 ++++++++++++++++++++++++-- 3 files changed, 30 insertions(+), 4 deletions(-) diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index bc20fe1..31ba9c7 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -328,7 +328,7 @@ static struct zram_meta *zram_meta_alloc(u64 disksize) goto free_meta; } - meta->mem_pool = zs_create_pool(GFP_NOIO | __GFP_HIGHMEM); + meta->mem_pool = zs_create_pool(GFP_NOIO | __GFP_HIGHMEM, NULL); if (!meta->mem_pool) { pr_err("Error creating memory pool\n"); goto free_table; diff --git a/include/linux/zsmalloc.h b/include/linux/zsmalloc.h index 05c2147..2c341d4 100644 --- a/include/linux/zsmalloc.h +++ b/include/linux/zsmalloc.h @@ -36,7 +36,11 @@ enum zs_mapmode { struct zs_pool; -struct zs_pool *zs_create_pool(gfp_t flags); +struct zs_ops { + int (*evict)(struct zs_pool *pool, unsigned long handle); +}; + +struct zs_pool *zs_create_pool(gfp_t flags, struct zs_ops *ops); void zs_destroy_pool(struct zs_pool *pool); unsigned long zs_malloc(struct zs_pool *pool, size_t size); diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index a2e417b..3dc7dae 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -221,6 +221,8 @@ struct zs_pool { gfp_t flags; /* allocation flags used when growing pool */ atomic_long_t pages_allocated; + + struct zs_ops *ops; }; /* @@ -256,9 +258,18 @@ static enum fullness_group lru_fg[] = { #ifdef CONFIG_ZPOOL +static int zs_zpool_evict(struct zs_pool *pool, unsigned long handle) +{ + return zpool_evict(pool, handle); +} + +static struct zs_ops zs_zpool_ops = { + .evict = zs_zpool_evict +}; + static void *zs_zpool_create(gfp_t gfp, struct zpool_ops *zpool_ops) { - return zs_create_pool(gfp); + return zs_create_pool(gfp, &zs_zpool_ops); } static void zs_zpool_destroy(void *pool) @@ -1019,7 +1030,7 @@ fail: * On success, a pointer to the newly created pool is returned, * otherwise NULL. */ -struct zs_pool *zs_create_pool(gfp_t flags) +struct zs_pool *zs_create_pool(gfp_t flags, struct zs_ops *ops) { int i, ovhd_size; struct zs_pool *pool; @@ -1046,6 +1057,7 @@ struct zs_pool *zs_create_pool(gfp_t flags) } pool->flags = flags; + pool->ops = ops; return pool; } @@ -1130,6 +1142,16 @@ unsigned long zs_malloc(struct zs_pool *pool, size_t size) } EXPORT_SYMBOL_GPL(zs_malloc); +/** + * zs_free - Free the handle from this pool. + * @pool: pool containing the handle + * @obj: the handle to free + * + * The caller must provide a valid handle that is contained + * in the provided pool. The caller must ensure this is + * not called after evict() has returned successfully for the + * handle. + */ void zs_free(struct zs_pool *pool, unsigned long obj) { struct page *first_page, *f_page; -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
