On Wed, Nov 27, 2013 at 04:54:05AM -0800, Christoph Hellwig wrote: > > int blkdev_issue_discard(struct block_device *bdev, sector_t sector, > > sector_t nr_sects, gfp_t gfp_mask, unsigned long flags) > > { > > - DECLARE_COMPLETION_ONSTACK(wait); > > struct request_queue *q = bdev_get_queue(bdev); > > int type = REQ_WRITE | REQ_DISCARD; > > - unsigned int max_discard_sectors, granularity; > > - int alignment; > > - struct bio_batch bb; > > struct bio *bio; > > int ret = 0; > > - struct blk_plug plug; > > > > if (!q) > > return -ENXIO; > > @@ -56,78 +34,28 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector, > > if (!blk_queue_discard(q)) > > return -EOPNOTSUPP; > > > > - /* Zero-sector (unknown) and one-sector granularities are the same. */ > > - granularity = max(q->limits.discard_granularity >> 9, 1U); > > - alignment = (bdev_discard_alignment(bdev) >> 9) % granularity; > > - > > - /* > > - * Ensure that max_discard_sectors is of the proper > > - * granularity, so that requests stay aligned after a split. > > - */ > > - max_discard_sectors = min(q->limits.max_discard_sectors, UINT_MAX >> 9); > > - max_discard_sectors -= max_discard_sectors % granularity; > > Seems like this is also missing the code to trim down the request to > be properly aligned to the device limit. I don't think our low-level > drivers are ready to handle this, and even if they were it should be a > separate change. The previous patch added that - that was blk_bio_discard_split(), which you commented on... -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html