1
linux/drivers
Jonathan Brassow b80aa7a0c2 dm raid1: fix EIO after log failure
This patch adds the ability to requeue write I/O to
core device-mapper when there is a log device failure.

If a write to the log produces and error, the pending writes are
put on the "failures" list.  Since the log is marked as failed,
they will stay on the failures list until a suspend happens.

Suspends come in two phases, presuspend and postsuspend.  We must
make sure that all the writes on the failures list are requeued
in the presuspend phase (a requirement of dm core).  This means
that recovery must be complete (because writes may be delayed
behind it) and the failures list must be requeued before we
return from presuspend.

The mechanisms to ensure recovery is complete (or stopped) was
already in place, but needed to be moved from postsuspend to
presuspend.  We rely on 'flush_workqueue' to ensure that the
mirror thread is complete and therefore, has requeued all writes
in the failures list.

Because we are using flush_workqueue, we must ensure that no
additional 'queue_work' calls will produce additional I/O
that we need to requeue (because once we return from
presuspend, we are unable to do anything about it).  'queue_work'
is called in response to the following functions:
- complete_resync_work = NA, recovery is stopped
- rh_dec (mirror_end_io) = NA, only calls 'queue_work' if it
                           is ready to recover the region
                           (recovery is stopped) or it needs
                           to clear the region in the log*
                           **this doesn't get called while
                           suspending**
- rh_recovery_end = NA, recovery is stopped
- rh_recovery_start = NA, recovery is stopped
- write_callback = 1) Writes w/o failures simply call
                   bio_endio -> mirror_end_io -> rh_dec
                   (see rh_dec above)
                   2) Writes with failures are put on
                   the failures list and queue_work is
                   called**
                   ** write_callbacks don't happen
                   during suspend **
- do_failures = NA, 'queue_work' not called if suspending
- add_mirror (initialization) = NA, only done on mirror creation
- queue_bio = NA, 1) delayed I/O scheduled before flush_workqueue
              is called.  2) No more I/Os are being issued.
              3) Re-attempted READs can still be handled.
              (Write completions are handled through rh_dec/
              write_callback - mention above - and do not
              use queue_bio.)

Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2008-02-08 02:11:35 +00:00
..
acorn/char
acpi ACPI: fix build warning 2008-02-07 04:24:01 -05:00
amba
ata ata_piix.c:piix_init_one() must be __devinit 2008-02-06 07:01:56 -05:00
atm
auxdisplay
base Driver core: Revert "Fix Firmware class name collision" 2008-02-07 11:31:46 -08:00
block Merge branch 'for-2.6.25' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc 2008-02-07 09:02:26 -08:00
bluetooth Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2008-02-05 10:09:07 -08:00
cdrom Merge branch 'for-2.6.25' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc 2008-02-07 09:02:26 -08:00
char Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2008-02-07 12:57:44 -08:00
clocksource
connector
cpufreq [CPUFREQ] fix configuration help message 2008-02-06 22:57:58 -05:00
cpuidle Revert "cpuidle: build fix for non-x86" 2008-02-07 04:16:34 -05:00
crypto
dca
dio dio: ARRAY_SIZE() cleanup 2008-02-05 09:44:23 -08:00
dma async_tx: replace 'int_en' with operation preparation flags 2008-02-06 10:12:18 -07:00
edac drivers/edac/i3000: document type promotion 2008-02-07 08:42:23 -08:00
eisa
firewire
firmware Merge branches 'release' and 'dmi' into release 2008-02-07 03:11:31 -05:00
gpio gpio: handle pca953{4,5,6,7,8} too 2008-02-06 10:41:15 -08:00
hid
hwmon leds: Standardise LED naming scheme 2008-02-07 09:47:00 +00:00
i2c deprecate obsolete pca9539 driver 2008-02-05 09:44:13 -08:00
ide Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev 2008-02-06 10:47:46 -08:00
ieee1394 ieee1394: sbp2: fix bogus s/g access change 2008-02-02 13:48:16 +01:00
infiniband RDMA/nes: Add a driver for NetEffect RNICs 2008-02-04 20:20:45 -08:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2008-02-07 12:57:44 -08:00
isdn drivers/isdn/hardware/eicon/debug.c: fix uninitialized var warning 2008-02-06 10:41:12 -08:00
leds leds: Add HP Jornada 6xx driver 2008-02-07 10:10:28 +00:00
lguest virtio: reset function 2008-02-04 23:50:03 +11:00
macintosh ppc: fix #ifdef-s in mediabay driver (take 2) 2008-02-06 02:57:50 +01:00
mca
md dm raid1: fix EIO after log failure 2008-02-08 02:11:35 +00:00
media Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2008-02-07 12:57:44 -08:00
message drivers/message/: Spelling fixes 2008-02-03 17:21:01 +02:00
mfd ASIC3 driver 2008-02-07 08:42:23 -08:00
misc Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2008-02-07 09:45:58 -08:00
mmc
mtd Merge git://git.infradead.org/mtd-2.6 2008-02-07 10:20:31 -08:00
net Merge branch 'for-linus' of git://git.o-hand.com/linux-rpurdie-leds 2008-02-07 09:45:14 -08:00
nubus nubus: kill drivers/nubus/nubus_syms.c 2008-02-05 09:44:23 -08:00
of [POWERPC] Create and hook up of_platform_device_shutdown 2008-02-06 16:29:59 +11:00
oprofile
parisc iommu sg merging: parisc: make iommu respect the segment size limits 2008-02-05 09:44:10 -08:00
parport parport_pc: detection for SuperIO IT87XX POST 2008-02-06 10:41:08 -08:00
pci Genericizing iova.[ch] 2008-02-06 10:41:01 -08:00
pcmcia drivers/pcmcia: add missing pci_dev_get 2008-02-05 09:44:09 -08:00
pnp Merge branches 'release', 'bugzilla-6217', 'bugzilla-6629', 'bugzilla-6933', 'bugzilla-7186', 'bugzilla-8269', 'bugzilla-8570', 'bugzilla-9139', 'bugzilla-9277', 'bugzilla-9341', 'bugzilla-9444', 'bugzilla-9614', 'bugzilla-9643' and 'bugzilla-9644' into release 2008-02-07 03:09:43 -05:00
power Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 2008-02-07 09:45:58 -08:00
ps3 ps3: use symbolic names for video modes 2008-02-06 10:41:17 -08:00
rapidio
rtc rtc: at91sam9 RTC support (RTT and/or RTC) 2008-02-06 10:41:14 -08:00
s390 calibrate_delay() must be __cpuinit 2008-02-06 10:41:08 -08:00
sbus
scsi scsi: megaraid: trivial drop duplicate mutex.h include 2008-02-06 11:15:41 -08:00
serial Merge branch 'for-2.6.25' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc 2008-02-07 09:02:26 -08:00
sh
sn
spi spi: remove more dev->power.power_state usage 2008-02-06 10:41:11 -08:00
ssb drivers/ssb/: Spelling fixes 2008-02-03 17:30:25 +02:00
tc
telephony
thermal the generic thermal sysfs driver 2008-02-01 23:12:19 -05:00
uio uio: nopage 2008-02-06 10:41:07 -08:00
usb Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/pci-2.6 2008-02-02 14:29:33 +11:00
video Merge branch 'for-linus' of git://git.o-hand.com/linux-rpurdie-backlight 2008-02-07 09:45:37 -08:00
virtio virtio: add missing #include <linux/delay.h> 2008-02-06 10:41:21 -08:00
w1 DS1WM: decouple host IRQ and INTR active state settings 2008-02-07 08:42:06 -08:00
watchdog drivers/watchdog/: Spelling fixes 2008-02-03 17:32:52 +02:00
xen
zorro
Kconfig Merge branches 'release' and 'menlo' into release 2008-02-07 03:18:04 -05:00
Makefile Merge branches 'release' and 'menlo' into release 2008-02-07 03:18:04 -05:00