From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1ifksL-0003bL-Ni for barebox@lists.infradead.org; Fri, 13 Dec 2019 13:20:59 +0000 From: Sascha Hauer Date: Fri, 13 Dec 2019 14:20:54 +0100 Message-Id: <20191213132055.7461-4-s.hauer@pengutronix.de> In-Reply-To: <20191213132055.7461-1-s.hauer@pengutronix.de> References: <20191213132055.7461-1-s.hauer@pengutronix.de> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH 3/4] block: Implement discard_range To: Barebox List This implements the discard_range hook. When a range of data is discarded then we do not have to read it from the device and can pass a zeroed buffer instead. Signed-off-by: Sascha Hauer --- common/block.c | 21 +++++++++++++++++++++ include/block.h | 3 +++ 2 files changed, 24 insertions(+) diff --git a/common/block.c b/common/block.c index 97cf5dc4de..8b43c3c83a 100644 --- a/common/block.c +++ b/common/block.c @@ -161,6 +161,14 @@ static int block_cache(struct block_device *blk, int block) dev_dbg(blk->dev, "%s: %d to %d\n", __func__, chunk->block_start, chunk->num); + if (chunk->block_start * BLOCKSIZE(blk) >= blk->discard_start && + chunk->block_start * BLOCKSIZE(blk) + writebuffer_io_len(blk, chunk) + <= blk->discard_start + blk->discard_size) { + memset(chunk->data, 0, writebuffer_io_len(blk, chunk)); + list_add(&chunk->list, &blk->buffered_blocks); + return 0; + } + ret = blk->ops->read(blk, chunk->data, chunk->block_start, writebuffer_io_len(blk, chunk)); if (ret) { @@ -337,11 +345,23 @@ static int block_op_flush(struct cdev *cdev) { struct block_device *blk = cdev->priv; + blk->discard_start = blk->discard_size = 0; + return writebuffer_flush(blk); } static int block_op_close(struct cdev *cdev) __alias(block_op_flush); +static int block_op_discard_range(struct cdev *cdev, loff_t count, loff_t offset) +{ + struct block_device *blk = cdev->priv; + + blk->discard_start = offset; + blk->discard_size = count; + + return 0; +} + static struct cdev_operations block_ops = { .read = block_op_read, #ifdef CONFIG_BLOCK_WRITE @@ -349,6 +369,7 @@ static struct cdev_operations block_ops = { #endif .close = block_op_close, .flush = block_op_flush, + .discard_range = block_op_discard_range, }; int blockdevice_register(struct block_device *blk) diff --git a/include/block.h b/include/block.h index 91377679b0..d35c4ecdf4 100644 --- a/include/block.h +++ b/include/block.h @@ -23,6 +23,9 @@ struct block_device { int rdbufsize; int blkmask; + loff_t discard_start; + loff_t discard_size; + struct list_head buffered_blocks; struct list_head idle_blocks; -- 2.24.0 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox