From 7b19b8d45b216ff3186f066b31937bdbde066f08 Mon Sep 17 00:00:00 2001 From: Robert Jennings Date: Fri, 28 Jan 2011 08:58:17 -0600 Subject: [PATCH] zram: Prevent overflow in logical block size On a 64K page kernel, the value PAGE_SIZE passed to blk_queue_logical_block_size would overflow the logical block size argument (resulting in setting it to 0). This patch sets the logical block size to 4096, using a new ZRAM_LOGICAL_BLOCK_SIZE constant. Signed-off-by: Robert Jennings Reviewed-by: Pekka Enberg Signed-off-by: Greg Kroah-Hartman --- drivers/staging/zram/zram_drv.c | 3 ++- drivers/staging/zram/zram_drv.h | 1 + 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c index 5ed4e75dc218..3c8ecab70e97 100644 --- a/drivers/staging/zram/zram_drv.c +++ b/drivers/staging/zram/zram_drv.c @@ -616,7 +616,8 @@ static int create_device(struct zram *zram, int device_id) * and n*PAGE_SIZED sized I/O requests. */ blk_queue_physical_block_size(zram->disk->queue, PAGE_SIZE); - blk_queue_logical_block_size(zram->disk->queue, PAGE_SIZE); + blk_queue_logical_block_size(zram->disk->queue, + ZRAM_LOGICAL_BLOCK_SIZE); blk_queue_io_min(zram->disk->queue, PAGE_SIZE); blk_queue_io_opt(zram->disk->queue, PAGE_SIZE); diff --git a/drivers/staging/zram/zram_drv.h b/drivers/staging/zram/zram_drv.h index a48155112b1e..408b2c067fc9 100644 --- a/drivers/staging/zram/zram_drv.h +++ b/drivers/staging/zram/zram_drv.h @@ -61,6 +61,7 @@ static const unsigned max_zpage_size = PAGE_SIZE / 4 * 3; #define SECTOR_SIZE (1 << SECTOR_SHIFT) #define SECTORS_PER_PAGE_SHIFT (PAGE_SHIFT - SECTOR_SHIFT) #define SECTORS_PER_PAGE (1 << SECTORS_PER_PAGE_SHIFT) +#define ZRAM_LOGICAL_BLOCK_SIZE 4096 /* Flags for zram pages (table[page_no].flags) */ enum zram_pageflags { -- 2.20.1