From: Yosry Ahmed Date: Wed, 5 Mar 2025 06:11:29 +0000 (+0000) Subject: mm: zpool: add interfaces for object read/write APIs X-Git-Tag: v6.15-rc1~81^2~168 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=9bbe033c75a56d72fc35e7c8ca6f3258d9782fa5;p=thirdparty%2Flinux.git mm: zpool: add interfaces for object read/write APIs Patch series "Switch zswap to object read/write APIs". This patch series updates zswap to use the new object read/write APIs defined by zsmalloc in [1], and remove the old object mapping APIs and the related code from zpool and zsmalloc. This patch (of 5): Zsmalloc introduced new APIs to read/write objects besides mapping them. Add the necessary zpool interfaces. Link: https://lkml.kernel.org/r/20250305061134.4105762-1-yosry.ahmed@linux.dev Link: https://lkml.kernel.org/r/20250305061134.4105762-2-yosry.ahmed@linux.dev Signed-off-by: Yosry Ahmed Reviewed-by: Sergey Senozhatsky Acked-by: Johannes Weiner Acked-by: Nhat Pham Cc: Chengming Zhou Cc: Herbert Xu Cc: Minchan Kim Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Andrew Morton --- diff --git a/include/linux/zpool.h b/include/linux/zpool.h index 5e6dc46b8cc4c..1784e735ee049 100644 --- a/include/linux/zpool.h +++ b/include/linux/zpool.h @@ -52,6 +52,16 @@ void *zpool_map_handle(struct zpool *pool, unsigned long handle, void zpool_unmap_handle(struct zpool *pool, unsigned long handle); + +void *zpool_obj_read_begin(struct zpool *zpool, unsigned long handle, + void *local_copy); + +void zpool_obj_read_end(struct zpool *zpool, unsigned long handle, + void *handle_mem); + +void zpool_obj_write(struct zpool *zpool, unsigned long handle, + void *handle_mem, size_t mem_len); + u64 zpool_get_total_pages(struct zpool *pool); @@ -90,6 +100,13 @@ struct zpool_driver { enum zpool_mapmode mm); void (*unmap)(void *pool, unsigned long handle); + void *(*obj_read_begin)(void *pool, unsigned long handle, + void *local_copy); + void (*obj_read_end)(void *pool, unsigned long handle, + void *handle_mem); + void (*obj_write)(void *pool, unsigned long handle, + void *handle_mem, size_t mem_len); + u64 (*total_pages)(void *pool); }; diff --git a/mm/zpool.c b/mm/zpool.c index 4bbd12d4b6599..378c2d1e5638f 100644 --- a/mm/zpool.c +++ b/mm/zpool.c @@ -320,6 +320,54 @@ void zpool_unmap_handle(struct zpool *zpool, unsigned long handle) zpool->driver->unmap(zpool->pool, handle); } +/** + * zpool_obj_read_begin() - Start reading from a previously allocated handle. + * @zpool: The zpool that the handle was allocated from + * @handle: The handle to read from + * @local_copy: A local buffer to use if needed. + * + * This starts a read operation of a previously allocated handle. The passed + * @local_copy buffer may be used if needed by copying the memory into. + * zpool_obj_read_end() MUST be called after the read is completed to undo any + * actions taken (e.g. release locks). + * + * Returns: A pointer to the handle memory to be read, if @local_copy is used, + * the returned pointer is @local_copy. + */ +void *zpool_obj_read_begin(struct zpool *zpool, unsigned long handle, + void *local_copy) +{ + return zpool->driver->obj_read_begin(zpool->pool, handle, local_copy); +} + +/** + * zpool_obj_read_end() - Finish reading from a previously allocated handle. + * @zpool: The zpool that the handle was allocated from + * @handle: The handle to read from + * @handle_mem: The pointer returned by zpool_obj_read_begin() + * + * Finishes a read operation previously started by zpool_obj_read_begin(). + */ +void zpool_obj_read_end(struct zpool *zpool, unsigned long handle, + void *handle_mem) +{ + zpool->driver->obj_read_end(zpool->pool, handle, handle_mem); +} + +/** + * zpool_obj_write() - Write to a previously allocated handle. + * @zpool: The zpool that the handle was allocated from + * @handle: The handle to read from + * @handle_mem: The memory to copy from into the handle. + * @mem_len: The length of memory to be written. + * + */ +void zpool_obj_write(struct zpool *zpool, unsigned long handle, + void *handle_mem, size_t mem_len) +{ + zpool->driver->obj_write(zpool->pool, handle, handle_mem, mem_len); +} + /** * zpool_get_total_pages() - The total size of the pool * @zpool: The zpool to check diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index 63c99db71dc1f..d84b300db64e7 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -507,6 +507,24 @@ static void zs_zpool_unmap(void *pool, unsigned long handle) zs_unmap_object(pool, handle); } +static void *zs_zpool_obj_read_begin(void *pool, unsigned long handle, + void *local_copy) +{ + return zs_obj_read_begin(pool, handle, local_copy); +} + +static void zs_zpool_obj_read_end(void *pool, unsigned long handle, + void *handle_mem) +{ + zs_obj_read_end(pool, handle, handle_mem); +} + +static void zs_zpool_obj_write(void *pool, unsigned long handle, + void *handle_mem, size_t mem_len) +{ + zs_obj_write(pool, handle, handle_mem, mem_len); +} + static u64 zs_zpool_total_pages(void *pool) { return zs_get_total_pages(pool); @@ -522,6 +540,9 @@ static struct zpool_driver zs_zpool_driver = { .free = zs_zpool_free, .map = zs_zpool_map, .unmap = zs_zpool_unmap, + .obj_read_begin = zs_zpool_obj_read_begin, + .obj_read_end = zs_zpool_obj_read_end, + .obj_write = zs_zpool_obj_write, .total_pages = zs_zpool_total_pages, };