From dd3d145d49c5816b79acc6761ebbd842bc50b0ee Mon Sep 17 00:00:00 2001 From: "Martin K. Petersen" Date: Mon, 11 Jan 2010 03:21:48 -0500 Subject: block: Fix discard alignment calculation and printing Discard alignment reporting for partitions was incorrect. Update to match the algorithm used elsewhere. The alignment can be negative (misaligned). Fix format string accordingly. Signed-off-by: Martin K. Petersen Signed-off-by: Jens Axboe --- include/linux/blkdev.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'include/linux/blkdev.h') diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 9b98173a8184..a41bcc8e140f 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1148,8 +1148,11 @@ static inline int queue_discard_alignment(struct request_queue *q) static inline int queue_sector_discard_alignment(struct request_queue *q, sector_t sector) { - return ((sector << 9) - q->limits.discard_alignment) - & (q->limits.discard_granularity - 1); + struct queue_limits *lim = &q->limits; + unsigned int alignment = (sector << 9) & (lim->discard_granularity - 1); + + return (lim->discard_granularity + lim->discard_alignment - alignment) + & (lim->discard_granularity - 1); } static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) -- cgit v1.2.3 From 17be8c245054b9c7786545af3ba3ca4e54cd4ad9 Mon Sep 17 00:00:00 2001 From: "Martin K. Petersen" Date: Mon, 11 Jan 2010 03:21:49 -0500 Subject: block: bdev_stack_limits wrapper DM does not want to know about partition offsets. Add a partition-aware wrapper that DM can use when stacking block devices. Signed-off-by: Martin K. Petersen Acked-by: Mike Snitzer Reviewed-by: Alasdair G Kergon Signed-off-by: Jens Axboe --- block/blk-settings.c | 22 ++++++++++++++++++++++ include/linux/blkdev.h | 2 ++ 2 files changed, 24 insertions(+) (limited to 'include/linux/blkdev.h') diff --git a/block/blk-settings.c b/block/blk-settings.c index 127f82551855..5eeb9e0d256e 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -639,6 +639,28 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, } EXPORT_SYMBOL(blk_stack_limits); +/** + * bdev_stack_limits - adjust queue limits for stacked drivers + * @t: the stacking driver limits (top device) + * @bdev: the component block_device (bottom) + * @start: first data sector within component device + * + * Description: + * Merges queue limits for a top device and a block_device. Returns + * 0 if alignment didn't change. Returns -1 if adding the bottom + * device caused misalignment. + */ +int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev, + sector_t start) +{ + struct request_queue *bq = bdev_get_queue(bdev); + + start += get_start_sect(bdev); + + return blk_stack_limits(t, &bq->limits, start << 9); +} +EXPORT_SYMBOL(bdev_stack_limits); + /** * disk_stack_limits - adjust queue limits for stacked drivers * @disk: MD/DM gendisk (top) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index a41bcc8e140f..5c8018977efa 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -938,6 +938,8 @@ extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt); extern void blk_set_default_limits(struct queue_limits *lim); extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, sector_t offset); +extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev, + sector_t offset); extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, sector_t offset); extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); -- cgit v1.2.3