Centos-kernel-stream-9/Documentation
Tejun Heo 920a4b1038 libata: implement libata.spindown_compat
Now that libata uses sd->manage_start_stop, libata spins down disk on
shutdown.  In an attempt to compensate libata's previous shortcoming,
some distros sync and spin down disks attached via libata in their
shutdown(8).  Some disks spin back up just to spin down again on
STANDBYNOW1 if the command is issued when the disk is spun down, so
this double spinning down causes problem.

This patch implements module parameter libata.spindown_compat which,
when set to one (default value), prevents libata from spinning down
disks on shutdown thus avoiding double spinning down.  Note that
libata spins down disks for suspend to mem and disk, so with
libata.spindown_compat set to one, disks should be properly spun down
in all cases without modifying shutdown(8).

shutdown(8) should be fixed eventually.  Some drive do spin up on
SYNCHRONZE_CACHE even when their cache is clean.  Those disks
currently spin up briefly when sd tries to shutdown the device and
then the machine powers off immediately, which can't be good for the
head.  We can't skip SYNCHRONIZE_CACHE during shudown as it can be
dangerous data integrity-wise.

So, this spindown_compat parameter is already scheduled for removal by
the end of the next year and here's what shutdown(8) should do.

  * Check whether /sys/modules/libata/parameters/spindown_compat
    exists.  If it does, write 0 to it.

  * For each libata harddisk {
	* Check whether /sys/class/scsi_disk/h:c:i:l/manage_start_stop
	  exists.  Iff it doesn't, synchronize cache and spin the disk
	  down as before.
  }

The above procedure will make shutdown(8) work properly with kernels
before this change, ones with this workaround and later ones without
it.

To accelerate shutdown(8) updates, if the compat mode is in use, this
patch prints BIG FAT warning for five seconds during shutdown (the
optimal interval to annoy the user just the right amount discovered by
hours of tireless usability testing).

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-05-11 18:01:04 -04:00
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ABI
DocBook
RCU
accounting
aoe
arm
auxdisplay
blackfin
block
cdrom
connector
console
cpu-freq
cris
crypto
device-mapper dm: delay target 2007-05-09 12:30:47 -07:00
driver-model
drivers/edac
dvb
early-userspace
fault-injection
fb Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial 2007-05-09 12:54:17 -07:00
filesystems
firmware_class
fujitsu/frv
hrtimer
hrtimers
hwmon
i2c
i2o
i386
ia64
infiniband
input
ioctl
isdn
kbuild
kdump
m68k
mips [MIPS] Delete Documentation/mips/pci/pci.README 2007-05-11 14:28:30 +01:00
netlabel
networking
parisc
pcmcia
power Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial 2007-05-09 12:54:17 -07:00
powerpc
s390
scsi
serial
sh
sound [ALSA] hda-codec - Add ALC861VD Lenovo support 2007-05-11 16:56:18 +02:00
sparc
spi
sysctl
telephony
uml
usb
video4linux Merge branch 'master' of ssh://master.kernel.org/pub/scm/linux/kernel/git/mchehab/v4l-dvb 2007-05-11 12:57:16 -07:00
vm SLUB: slabinfo upgrade 2007-05-09 12:30:44 -07:00
w1
watchdog
x86_64
00-INDEX
BUG-HUNTING
Changes
CodingStyle
DMA-API.txt
DMA-ISA-LPC.txt
DMA-mapping.txt
HOWTO
IO-mapping.txt
IPMI.txt
IRQ-affinity.txt
IRQ.txt
MSI-HOWTO.txt
ManagementStyle
PCIEBUS-HOWTO.txt
README.DAC960
README.cycladesZ
SAK.txt
SecurityBugs
SubmitChecklist SubmitChecklist: add -W help 2007-05-11 08:29:35 -07:00
SubmittingDrivers
SubmittingPatches doc: what a patch series is 2007-05-09 12:30:50 -07:00
VGA-softcursor.txt
applying-patches.txt
atomic_ops.txt
basic_profiling.txt
binfmt_misc.txt
cachetlb.txt
cciss.txt
cli-sti-removal.txt
computone.txt
cpqarray.txt
cpu-hotplug.txt Add suspend-related notifications for CPU hotplug 2007-05-09 12:30:56 -07:00
cpu-load.txt
cpusets.txt
cputopology.txt
dcdbas.txt
debugging-modules.txt
dell_rbu.txt
devices.txt
digiepca.txt
dnotify.txt
dontdiff
ecryptfs.txt
eisa.txt
exception.txt
feature-removal-schedule.txt libata: implement libata.spindown_compat 2007-05-11 18:01:04 -04:00
floppy.txt
gpio.txt Documentation/gpio.txt mentions GENERIC_GPIO 2007-05-11 08:29:32 -07:00
hayes-esp.txt
highuid.txt
hpet.txt
hw_random.txt
ide.txt
initrd.txt
io_ordering.txt
ioctl-number.txt
iostats.txt
irqflags-tracing.txt
isapnp.txt
java.txt
kernel-doc-nano-HOWTO.txt
kernel-docs.txt
kernel-parameters.txt Doc Fix: remove mention of combined mode-related kernel parameters 2007-05-09 20:15:47 -04:00
keys-request-key.txt
keys.txt
kobject.txt
kprobes.txt
kref.txt Fix wrong identifier name in Documentation/kref.txt 2007-05-11 19:07:14 +02:00
laptop-mode.txt
ldm.txt
leds-class.txt
local_ops.txt
lockdep-design.txt
locks.txt
logo.gif
logo.txt
magic-number.txt
mandatory.txt
mca.txt
md.txt md: allow reshape_position for md arrays to be set via sysfs 2007-05-09 12:30:57 -07:00
memory-barriers.txt
memory.txt
mono.txt
moxa-smartio
mtrr.txt
mutex-design.txt
nbd.txt
nfsroot.txt
nmi_watchdog.txt
nommu-mmap.txt
numastat.txt
oops-tracing.txt
paride.txt
parport-lowlevel.txt
parport.txt
pci-error-recovery.txt
pci.txt
pcieaer-howto.txt
pi-futex.txt
pm.txt
pnp.txt
preempt-locking.txt
prio_tree.txt
ramdisk.txt
rbtree.txt
riscom8.txt
robust-futex-ABI.txt
robust-futexes.txt
rocket.txt
rpc-cache.txt
rt-mutex-design.txt
rt-mutex.txt
rtc.txt
sched-arch.txt
sched-coding.txt
sched-design.txt
sched-domains.txt
sched-stats.txt
serial-console.txt
sgi-ioc4.txt
sgi-visws.txt
sharedsubtree.txt
smart-config.txt
smp.txt
sony-laptop.txt
sonypi.txt
sparse.txt
specialix.txt
spinlocks.txt
stable_api_nonsense.txt
stable_kernel_rules.txt
stallion.txt
svga.txt
sx.txt
sysrq.txt
thinkpad-acpi.txt
time_interpolators.txt
tipar.txt
tty.txt
unicode.txt
unshare.txt
video-output.txt
voyager.txt
xterm-linux.xpm
zorro.txt

README.cycladesZ

The Cyclades-Z must have firmware loaded onto the card before it will
operate.  This operation should be performed during system startup,

The firmware, loader program and the latest device driver code are
available from Cyclades at
    ftp://ftp.cyclades.com/pub/cyclades/cyclades-z/linux/