From f8dfcffd0472a0f353f34a567ad3f53568914d04 Mon Sep 17 00:00:00 2001
From: NeilBrown <neilb@suse.de>
Date: Tue, 12 Mar 2013 12:18:06 +1100
Subject: md/raid5: ensure sync and DISCARD don't happen at the same time.
A number of problems can occur due to races between
resync/recovery and discard.
- if sync_request calls handle_stripe() while a discard is
happening on the stripe, it might call handle_stripe_clean_event
before all of the individual discard requests have completed
(so some devices are still locked, but not all).
Since commit ca64cae96037de16e4af92678814f5d4bf0c1c65
md/raid5: Make sure we clear R5_Discard when discard is finished.
this will cause R5_Discard to be cleared for the parity device,
so handle_stripe_clean_event() will not be called when the other
devices do become unlocked, so their ->written will not be cleared.
This ultimately leads to a WARN_ON in init_stripe and a lock-up.
- If handle_stripe_clean_event() does clear R5_UPTODATE at an awkward
time for resync, it can lead to s->uptodate being less than disks
in handle_parity_checks5(), which triggers a BUG (because it is
one).
So:
- keep R5_Discard on the parity device until all other devices have
completed their discard request
- make sure we don't try to have a 'discard' and a 'sync' action at
the same time.
This involves a new stripe flag to we know when a 'discard' is
happening, and the use of R5_Overlap on the parity disk so when a
discard is wanted while a sync is active, so we know to wake up
the discard at the appropriate time.
Discard support for RAID5 was added in 3.7, so this is suitable for
any -stable kernel since 3.7.
Cc: stable@vger.kernel.org (v3.7+)
Reported-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Tested-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
---
drivers/md/raid5.h | 1 +
1 file changed, 1 insertion(+)
(limited to 'drivers/md/raid5.h')
diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h
index 18b2c4a8a1fd..050a334e89c1 100644
--- a/drivers/md/raid5.h
+++ b/drivers/md/raid5.h
@@ -323,6 +323,7 @@ enum {
STRIPE_COMPUTE_RUN,
STRIPE_OPS_REQ_PENDING,
STRIPE_ON_UNPLUG_LIST,
+ STRIPE_DISCARD,
};
/*
--
cgit
From 238f5908bd48f9e2f4668e0289e88cba969d710c Mon Sep 17 00:00:00 2001
From: Paul Bolle <pebolle@tiscali.nl>
Date: Mon, 11 Mar 2013 11:27:44 +0100
Subject: md: remove CONFIG_MULTICORE_RAID456 entirely
Once instance of this Kconfig macro remained after commit
51acbcec6c42b24482bac18e42befc822524535d ("md: remove
CONFIG_MULTICORE_RAID456"). Remove that one too. And, while we're at it,
also remove it from the defconfig files that carry it.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: NeilBrown <neilb@suse.de>
---
arch/tile/configs/tilegx_defconfig | 1 -
arch/tile/configs/tilepro_defconfig | 1 -
drivers/md/raid5.h | 4 ----
3 files changed, 6 deletions(-)
(limited to 'drivers/md/raid5.h')
diff --git a/arch/tile/configs/tilegx_defconfig b/arch/tile/configs/tilegx_defconfig
index 8c5eff6d6df5..47684815e5c8 100644
--- a/arch/tile/configs/tilegx_defconfig
+++ b/arch/tile/configs/tilegx_defconfig
@@ -330,7 +330,6 @@ CONFIG_MD_RAID0=m
CONFIG_MD_RAID1=m
CONFIG_MD_RAID10=m
CONFIG_MD_RAID456=m
-CONFIG_MULTICORE_RAID456=y
CONFIG_MD_FAULTY=m
CONFIG_BLK_DEV_DM=m
CONFIG_DM_DEBUG=y
diff --git a/arch/tile/configs/tilepro_defconfig b/arch/tile/configs/tilepro_defconfig
index e7a3dfcbcda7..dd2b8f0c631f 100644
--- a/arch/tile/configs/tilepro_defconfig
+++ b/arch/tile/configs/tilepro_defconfig
@@ -324,7 +324,6 @@ CONFIG_MD_RAID0=m
CONFIG_MD_RAID1=m
CONFIG_MD_RAID10=m
CONFIG_MD_RAID456=m
-CONFIG_MULTICORE_RAID456=y
CONFIG_MD_FAULTY=m
CONFIG_BLK_DEV_DM=m
CONFIG_DM_DEBUG=y
diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h
index 050a334e89c1..b0b663b119a8 100644
--- a/drivers/md/raid5.h
+++ b/drivers/md/raid5.h
@@ -221,10 +221,6 @@ struct stripe_head {
struct stripe_operations {
int target, target2;
enum sum_check_flags zero_sum_result;
- #ifdef CONFIG_MULTICORE_RAID456
- unsigned long request;
- wait_queue_head_t wait_for_ops;
- #endif
} ops;
struct r5dev {
/* rreq and rvec are used for the replacement device when
--
cgit