From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754573Ab2ECGlQ (ORCPT ); Thu, 3 May 2012 02:41:16 -0400 Received: from LGEMRELSE7Q.lge.com ([156.147.1.151]:62341 "EHLO LGEMRELSE7Q.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754451Ab2ECGlO (ORCPT ); Thu, 3 May 2012 02:41:14 -0400 X-AuditID: 9c930197-b7badae000000cfd-38-4fa22888765c From: Minchan Kim To: Greg Kroah-Hartman , Seth Jennings , Nitin Gupta , Dan Magenheimer , Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Minchan Kim , Konrad Rzeszutek Wilk Subject: [PATCH 3/4] zsmalloc use zs_handle instead of void * Date: Thu, 3 May 2012 15:40:41 +0900 Message-Id: <1336027242-372-3-git-send-email-minchan@kernel.org> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1336027242-372-1-git-send-email-minchan@kernel.org> References: <1336027242-372-1-git-send-email-minchan@kernel.org> X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We should use zs_handle instead of void * to avoid any confusion. Without this, users may just treat zs_malloc return value as a pointer and try to deference it. Cc: Dan Magenheimer Cc: Konrad Rzeszutek Wilk Signed-off-by: Minchan Kim --- drivers/staging/zcache/zcache-main.c | 8 ++++---- drivers/staging/zram/zram_drv.c | 8 ++++---- drivers/staging/zram/zram_drv.h | 2 +- drivers/staging/zsmalloc/zsmalloc-main.c | 28 ++++++++++++++-------------- drivers/staging/zsmalloc/zsmalloc.h | 15 +++++++++++---- 5 files changed, 34 insertions(+), 27 deletions(-) diff --git a/drivers/staging/zcache/zcache-main.c b/drivers/staging/zcache/zcache-main.c index 2734dac..9b06948 100644 --- a/drivers/staging/zcache/zcache-main.c +++ b/drivers/staging/zcache/zcache-main.c @@ -700,12 +700,12 @@ static struct zv_hdr *zv_create(struct zs_pool *pool, uint32_t pool_id, struct zv_hdr *zv; u32 size = clen + sizeof(struct zv_hdr); int chunks = (size + (CHUNK_SIZE - 1)) >> CHUNK_SHIFT; - void *handle = NULL; + zs_handle handle; BUG_ON(!irqs_disabled()); BUG_ON(chunks >= NCHUNKS); handle = zs_malloc(pool, size); - if (!handle) + if (zs_handle_invalid(handle)) goto out; atomic_inc(&zv_curr_dist_counts[chunks]); atomic_inc(&zv_cumul_dist_counts[chunks]); @@ -721,7 +721,7 @@ out: return handle; } -static void zv_free(struct zs_pool *pool, void *handle) +static void zv_free(struct zs_pool *pool, zs_handle handle) { unsigned long flags; struct zv_hdr *zv; @@ -743,7 +743,7 @@ static void zv_free(struct zs_pool *pool, void *handle) local_irq_restore(flags); } -static void zv_decompress(struct page *page, void *handle) +static void zv_decompress(struct page *page, zs_handle handle) { unsigned int clen = PAGE_SIZE; char *to_va; diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c index 685d612..7e42aa2 100644 --- a/drivers/staging/zram/zram_drv.c +++ b/drivers/staging/zram/zram_drv.c @@ -135,7 +135,7 @@ static void zram_set_disksize(struct zram *zram, size_t totalram_bytes) static void zram_free_page(struct zram *zram, size_t index) { - void *handle = zram->table[index].handle; + zs_handle handle = zram->table[index].handle; if (unlikely(!handle)) { /* @@ -317,7 +317,7 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, int ret; u32 store_offset; size_t clen; - void *handle; + zs_handle handle; struct zobj_header *zheader; struct page *page, *page_store; unsigned char *user_mem, *cmem, *src, *uncmem = NULL; @@ -406,7 +406,7 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, } handle = zs_malloc(zram->mem_pool, clen + sizeof(*zheader)); - if (!handle) { + if (zs_handle_invalid(handle)) { pr_info("Error allocating memory for compressed " "page: %u, size=%zu\n", index, clen); ret = -ENOMEM; @@ -592,7 +592,7 @@ void __zram_reset_device(struct zram *zram) /* Free all pages that are still in this zram device */ for (index = 0; index < zram->disksize >> PAGE_SHIFT; index++) { - void *handle = zram->table[index].handle; + zs_handle handle = zram->table[index].handle; if (!handle) continue; diff --git a/drivers/staging/zram/zram_drv.h b/drivers/staging/zram/zram_drv.h index fbe8ac9..07d3192 100644 --- a/drivers/staging/zram/zram_drv.h +++ b/drivers/staging/zram/zram_drv.h @@ -81,7 +81,7 @@ enum zram_pageflags { /* Allocated for each disk page */ struct table { - void *handle; + zs_handle handle; u16 size; /* object size (excluding header) */ u8 count; /* object ref count (not yet used) */ u8 flags; diff --git a/drivers/staging/zsmalloc/zsmalloc-main.c b/drivers/staging/zsmalloc/zsmalloc-main.c index 4496737..51074fa 100644 --- a/drivers/staging/zsmalloc/zsmalloc-main.c +++ b/drivers/staging/zsmalloc/zsmalloc-main.c @@ -247,7 +247,7 @@ static void *obj_location_to_handle(struct page *page, unsigned long obj_idx) } /* Decode pair from the given object handle */ -static void obj_handle_to_location(void *handle, struct page **page, +static void obj_handle_to_location(zs_handle handle, struct page **page, unsigned long *obj_idx) { unsigned long hval = (unsigned long)handle; @@ -571,9 +571,9 @@ EXPORT_SYMBOL_GPL(zs_destroy_pool); * otherwise NULL. * Allocation requests with size > ZS_MAX_ALLOC_SIZE will fail. */ -void *zs_malloc(struct zs_pool *pool, size_t size) +zs_handle zs_malloc(struct zs_pool *pool, size_t size) { - void *obj; + zs_handle handle; struct link_free *link; int class_idx; struct size_class *class; @@ -602,8 +602,8 @@ void *zs_malloc(struct zs_pool *pool, size_t size) class->pages_allocated += class->pages_per_zspage; } - obj = first_page->freelist; - obj_handle_to_location(obj, &m_page, &m_objidx); + handle = first_page->freelist; + obj_handle_to_location(handle, &m_page, &m_objidx); m_offset = obj_idx_to_offset(m_page, m_objidx, class->size); link = (struct link_free *)kmap_atomic(m_page) + @@ -617,11 +617,11 @@ void *zs_malloc(struct zs_pool *pool, size_t size) fix_fullness_group(pool, first_page); spin_unlock(&class->lock); - return obj; + return handle; } EXPORT_SYMBOL_GPL(zs_malloc); -void zs_free(struct zs_pool *pool, void *obj) +void zs_free(struct zs_pool *pool, zs_handle handle) { struct link_free *link; struct page *first_page, *f_page; @@ -631,10 +631,10 @@ void zs_free(struct zs_pool *pool, void *obj) struct size_class *class; enum fullness_group fullness; - if (unlikely(!obj)) + if (unlikely(zs_handle_invalid(handle))) return; - obj_handle_to_location(obj, &f_page, &f_objidx); + obj_handle_to_location(handle, &f_page, &f_objidx); first_page = get_first_page(f_page); get_zspage_mapping(first_page, &class_idx, &fullness); @@ -648,7 +648,7 @@ void zs_free(struct zs_pool *pool, void *obj) + f_offset); link->next = first_page->freelist; kunmap_atomic(link); - first_page->freelist = obj; + first_page->freelist = handle; first_page->inuse--; fullness = fix_fullness_group(pool, first_page); @@ -672,7 +672,7 @@ EXPORT_SYMBOL_GPL(zs_free); * this function. When done with the object, it must be unmapped using * zs_unmap_object */ -void *zs_map_object(struct zs_pool *pool, void *handle) +void *zs_map_object(struct zs_pool *pool, zs_handle handle) { struct page *page; unsigned long obj_idx, off; @@ -682,7 +682,7 @@ void *zs_map_object(struct zs_pool *pool, void *handle) struct size_class *class; struct mapping_area *area; - BUG_ON(!handle); + BUG_ON(zs_handle_invalid(handle)); obj_handle_to_location(handle, &page, &obj_idx); get_zspage_mapping(get_first_page(page), &class_idx, &fg); @@ -712,7 +712,7 @@ void *zs_map_object(struct zs_pool *pool, void *handle) } EXPORT_SYMBOL_GPL(zs_map_object); -void zs_unmap_object(struct zs_pool *pool, void *handle) +void zs_unmap_object(struct zs_pool *pool, zs_handle handle) { struct page *page; unsigned long obj_idx, off; @@ -722,7 +722,7 @@ void zs_unmap_object(struct zs_pool *pool, void *handle) struct size_class *class; struct mapping_area *area; - BUG_ON(!handle); + BUG_ON(zs_handle_invalid(handle)); obj_handle_to_location(handle, &page, &obj_idx); get_zspage_mapping(get_first_page(page), &class_idx, &fg); diff --git a/drivers/staging/zsmalloc/zsmalloc.h b/drivers/staging/zsmalloc/zsmalloc.h index 949384e..1ba6d0c 100644 --- a/drivers/staging/zsmalloc/zsmalloc.h +++ b/drivers/staging/zsmalloc/zsmalloc.h @@ -16,15 +16,22 @@ #include struct zs_pool; +typedef void * zs_handle; + +/* + * zs_malloc's caller should use zs_handle_invalid instead of if (!handle) + * to test successful allocation. + */ +#define zs_handle_invalid(zs_handle) !zs_handle struct zs_pool *zs_create_pool(const char *name, gfp_t flags); void zs_destroy_pool(struct zs_pool *pool); -void *zs_malloc(struct zs_pool *pool, size_t size); -void zs_free(struct zs_pool *pool, void *obj); +zs_handle zs_malloc(struct zs_pool *pool, size_t size); +void zs_free(struct zs_pool *pool, zs_handle handle); -void *zs_map_object(struct zs_pool *pool, void *handle); -void zs_unmap_object(struct zs_pool *pool, void *handle); +void *zs_map_object(struct zs_pool *pool, zs_handle handle); +void zs_unmap_object(struct zs_pool *pool, zs_handle handle); u64 zs_get_total_size_bytes(struct zs_pool *pool); -- 1.7.9.5