From mboxrd@z Thu Jan 1 00:00:00 1970 From: Denis Semakin Subject: Re: dm table: add support for secure erase forwarding [was: Re: Adaptation secure erase forwarding for 4.1x kernels] Date: Mon, 26 Mar 2018 10:45:33 +0300 (MSK) Message-ID: <1996070847.39629.1522050333423.JavaMail.zimbra@omprussia.ru> References: <1496940834.549721.1520933025411.JavaMail.zimbra@omprussia.ru> <20180322151045.GA27598@redhat.com> <695931032.318989.1521816469739.JavaMail.zimbra@omprussia.ru> <20180323153844.GA4914@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180323153844.GA4914@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: snitzer Cc: dm-devel List-Id: dm-devel.ids Hi, sorry for my misunderstanding. >Thinking further, it is absolutely needed, otherwise dm-stripe.c won't >be able to use the optimization I mentioned above. In addition, other >targets shouldn't be getting REQ_OP_SECURE_ERASE unless there is a real >need. ti->num_secure_erase_bios will allow for a much safer and >controlled rollout of this support. Ok. I got it. >As my previous email elaborated, ti->num_secure_erase_bios is the right >way forward. Then a patch for this may look like: >From 2b9dfd5af813023cdaded4d91b4c25cec8a1783d Mon Sep 17 00:00:00 2001 From: Denis Semakin Date: Mon, 26 Mar 2018 10:44:14 +0300 Subject: [PATCH] Add num_secure_erase_bios field Signed-off-by: Denis Semakin --- drivers/md/dm-linear.c | 1 + drivers/md/dm-table.c | 3 +++ include/linux/device-mapper.h | 2 ++ 3 files changed, 6 insertions(+) diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c index d5f8eff..ff751b0 100644 --- a/drivers/md/dm-linear.c +++ b/drivers/md/dm-linear.c @@ -59,6 +59,7 @@ static int linear_ctr(struct dm_target *ti, unsigned int argc, char **argv) ti->num_flush_bios = 1; ti->num_discard_bios = 1; + ti->num_secure_erase_bios = 1; ti->num_write_same_bios = 1; ti->num_write_zeroes_bios = 1; ti->private = lc; diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index d857369..0acffdb 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -1863,6 +1863,9 @@ static bool dm_table_supports_secure_erase(struct dm_table *t) for (i = 0; i < dm_table_get_num_targets(t); i++) { ti = dm_table_get_target(t, i); + if (!ti->num_secure_erase_bios) + return false; + if (!ti->type->iterate_devices || ti->type->iterate_devices(ti, device_not_secure_erase_capable, NULL)) return false; diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index 1e2426c..233ac8f 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -267,6 +267,8 @@ struct dm_target { */ unsigned num_discard_bios; + unsigned num_secure_erase_bios; + /* * The number of WRITE SAME bios that will be submitted to the target. * The bio number can be accessed with dm_bio_get_target_bio_nr. -- 1.9.1 What do you think? Denis.