From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Nicholas A. Bellinger" Subject: [PATCH 2/3] tcm/iblock: Add UNMAP / Block DISCARD support Date: Mon, 27 Sep 2010 15:51:39 -0700 Message-ID: <1285627899-6471-1-git-send-email-nab@linux-iscsi.org> Return-path: Received: from nm13.bullet.mail.sp2.yahoo.com ([98.139.91.83]:25695 "HELO nm13.bullet.mail.sp2.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S933308Ab0I0Wvp (ORCPT ); Mon, 27 Sep 2010 18:51:45 -0400 Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: linux-scsi , linux-kernel Cc: Christoph Hellwig , "Martin K. Petersen" , Douglas Gilbert , Jens Axboe , FUJITA Tomonori , Mike Christie , Hannes Reinecke , James Bottomley , Konrad Rzeszutek Wilk , Boaz Harrosh , Richard Sharpe , Nicholas Bellinger From: Nicholas Bellinger This patch adds UNMAP emulation support using Block layer DISCARD in iblock_emulate_scsi_cdb() -> transport_generic_unmap(). This includes the use of blk_queue_discard() in iblock_create_virtdevice() to determine when to set DEV_ATTRIB(dev)->emulate_tpe=1 to signal to TCM Core to perform the necessary control CDB emulation for TPE=1 / UNMAP. Signed-off-by: Nicholas A. Bellinger --- drivers/target/target_core_iblock.c | 19 ++++++++++++++++++- 1 files changed, 18 insertions(+), 1 deletions(-) diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c index 1b148f5..089f353 100644 --- a/drivers/target/target_core_iblock.c +++ b/drivers/target/target_core_iblock.c @@ -221,6 +221,16 @@ static struct se_device *iblock_create_virtdevice( */ if (__iblock_do_sync_cache(dev) == 0) ib_dev->ibd_flags |= IBDF_BDEV_ISSUE_FLUSH; + /* + * Check if the underlying struct block_device request_queue supports + * the QUEUE_FLAG_DISCARD bit for UNMAP/WRITE_SAME in SCSI + TRIM + * in ATA and we need to set TPE=1 + */ + if (blk_queue_discard(bdev_get_queue(bd))) { + DEV_ATTRIB(dev)->emulate_tpe = 1; + printk(KERN_INFO "IBLOCK: Enabling BLOCK Discard" + " and TPE=1 emulation\n"); + } return dev; @@ -446,8 +456,10 @@ static int iblock_emulate_read_cap16(struct se_task *task) static int iblock_emulate_scsi_cdb(struct se_task *task) { - int ret; + struct iblock_dev *ibd = (struct iblock_dev *) task->se_dev->dev_ptr; + struct block_device *bd = ibd->ibd_bd; struct se_cmd *cmd = TASK_CMD(task); + int ret; switch (T_TASK(cmd)->t_task_cdb[0]) { case INQUIRY: @@ -490,6 +502,11 @@ static int iblock_emulate_scsi_cdb(struct se_task *task) if (ret < 0) return ret; break; + case UNMAP: + ret = transport_generic_unmap(cmd, bd); + if (ret < 0) + return ret; + break; case ALLOW_MEDIUM_REMOVAL: case ERASE: case REZERO_UNIT: -- 1.5.6.5