Vladimir Davydov 53d85c9856 cleancache: forbid overriding cleancache_ops ... Currently, cleancache_register_ops returns the previous value of cleancache_ops to allow chaining. However, chaining, as it is implemented now, is extremely dangerous due to possible pool id collisions. Suppose, a new cleancache driver is registered after the previous one assigned an id to a super block. If the new driver assigns the same id to another super block, which is perfectly possible, we will have two different filesystems using the same id. No matter if the new driver implements chaining or not, we are likely to get data corruption with such a configuration eventually. This patch therefore disables the ability to override cleancache_ops altogether as potentially dangerous. If there is already cleancache driver registered, all further calls to cleancache_register_ops will return EBUSY. Since no user of cleancache implements chaining, we only need to make minor changes to the code outside the cleancache core. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Stefan Hengelein <ilendir@googlemail.com> Cc: Florian Schmaus <fschmaus@gmail.com> Cc: Andor Daam <andor.daam@googlemail.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Bob Liu <lliubbo@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2015-04-14 16:49:03 -07:00
..
ABI	Staging driver patches for 4.1-rc1	2015-04-13 17:37:33 -07:00
accounting
acpi	Merge branch 'x86-ras-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-04-13 13:33:20 -07:00
aoe
arm	ARM: SoC platform changes	2015-02-17 09:27:54 -08:00
arm64	arm64: Emulate SETEND for AArch32 tasks	2015-01-23 17:11:44 +00:00
auxdisplay
backlight
blackfin	Documentation: fix blackfin gptimers-example build errors	2015-01-28 12:07:58 -07:00
block
blockdev
bus-devices
cdrom
cgroups	Merge branch 'for-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup	2015-04-13 16:47:11 -07:00
cma	cma: debug: document new debugfs interface	2015-04-14 16:49:00 -07:00
connector
console
cpu-freq	intel_pstate: Add num_pstates to sysfs	2015-01-30 01:52:17 +01:00
cpuidle
cris
crypto
development-process
device-mapper	dm crypt: add 'submit_from_crypt_cpus' option	2015-02-16 11:11:15 -05:00
devicetree	Staging driver patches for 4.1-rc1	2015-04-13 17:37:33 -07:00
dmaengine	Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma	2015-02-18 08:49:20 -08:00
DocBook	KGDB/KDB New:	2015-02-20 15:13:29 -08:00
driver-model	Staging drivers patches for 3.20-rc1	2015-02-15 11:30:39 -08:00
dvb
early-userspace
EDID
extcon
fault-injection
fb
filesystems	ocfs2: update web page + git tree in documentation	2015-02-28 09:57:50 -08:00
firmware_class
fmc
frv
gpio	gpio: board.txt: Fix the gpio name example	2015-01-28 11:14:00 -07:00
hid
hwmon	hwmon: (it87) Add support for IT8620E	2015-04-05 06:01:00 -07:00
i2c	i2c: fix reference to functionality constants definition	2015-02-19 16:57:48 +01:00
i2o
ia64	virtual: Documentation: simplify and generalize paravirt_ops.txt	2015-02-13 17:15:44 +10:30
ide
infiniband
input	Input: alps - document stick behavior for protocol V2	2015-04-05 11:48:35 -07:00
ioctl
isdn
ja_JP
kbuild	Merge branch 'misc' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild	2015-02-19 10:31:37 -08:00
kdump
ko_KR
laptops
leds
locking	Documentation changes for 3.20	2015-02-11 13:03:11 -08:00
m68k
memory-devices
metag
mic
mips
misc-devices	Documentation/misc-devices/mei: Fix indentation of embedded code.	2015-01-29 12:56:20 -07:00
mmc
mn10300
mtd
namespaces
netlabel
networking	Documentation changes for 3.20	2015-02-11 13:03:11 -08:00
nfc
nios2
parisc
PCI	PCI: Clarify policy for vendor IDs in pci.txt	2015-04-09 13:34:02 -05:00
pcmcia
phy
platform
power	Merge remote-tracking branches 'regulator/topic/mode', 'regulator/topic/notifier', 'regulator/topic/palmas', 'regulator/topic/qcom' and 'regulator/topic/stw481x' into regulator-next	2015-04-10 19:16:03 +01:00
powerpc
pps
prctl
pti
ptp
rapidio
RCU	Merge branches 'doc.2015.01.07a', 'fixes.2015.01.15a', 'preempt.2015.01.06a', 'srcu.2015.01.06a', 'stall.2015.01.16a' and 'torture.2015.01.11a' into HEAD	2015-01-15 23:34:34 -08:00
s390	s390/docs: Remove section about script debugging from Debugging390.txt	2015-01-15 11:11:14 +01:00
scheduler	doc: brief user documentation for completion	2015-01-30 11:19:25 -07:00
scsi	genirq: Remove the deprecated 'IRQF_DISABLED' request_irq() flag entirely	2015-03-05 20:53:06 +01:00
security	KEYS: Make /proc/keys unconditional if CONFIG_KEYS=y	2015-01-22 22:34:32 +00:00
serial
sh
sound
spi	Merge remote-tracking branches 'spi/topic/spidev' and 'spi/topic/spidev-test' into spi-next	2015-04-11 23:09:31 +01:00
sysctl	watchdog: enable the new user interface of the watchdog mechanism	2015-04-14 16:48:59 -07:00
target	Documentation/target: Update fabric_ops to latest code	2015-01-06 13:46:49 -08:00
thermal	Documentation: thermal: document of_cpufreq_cooling_register()	2015-01-06 14:39:17 -04:00
timers
tpm
trace	Char / Misc patches for 3.20-rc1	2015-02-15 10:48:44 -08:00
usb	usb: patches for v4.1 merge window	2015-03-24 22:57:49 +01:00
vDSO
video4linux	MODULE_DEVICE_TABLE: fix some callsites	2015-02-13 21:21:40 -08:00
virtual	Features and fixes for 4.1 (kvm/next)	2015-04-07 18:10:03 +02:00
vm	cleancache: forbid overriding cleancache_ops	2015-04-14 16:49:03 -07:00
w1
watchdog
wimax
x86	x86/mm/KASLR: Propagate KASLR status to kernel proper	2015-04-03 15:26:15 +02:00
xtensa
zh_CN
00-INDEX	Update of Documentation/dmaengine/00-INDEX	2014-12-29 15:28:24 -07:00
applying-patches.txt
assoc_array.txt
atomic_ops.txt
bad_memory.txt
basic_profiling.txt
bcache.txt
binfmt_misc.txt
braille-console.txt
bt8xxgpio.txt
btmrvl.txt
BUG-HUNTING
bus-virt-phys-mapping.txt
cachetlb.txt	rmap: drop support of non-linear mappings	2015-02-10 14:30:31 -08:00
Changes	Documentation: GNU is frequently spelled Gnu	2014-12-29 15:33:17 -07:00
circular-buffers.txt
clk.txt	clk: Add rate constraints to clocks	2015-02-02 14:23:42 -08:00
coccinelle.txt
CodeOfConflict	Code of Conflict	2015-02-27 11:44:24 -08:00
CodingStyle	CodingStyle: enable emacs display of trailing whitespace	2015-01-28 12:05:46 -07:00
cpu-hotplug.txt
cpu-load.txt
cputopology.txt
crc32.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt
dell_rbu.txt
devices.txt
digsig.txt
DMA-API-HOWTO.txt
DMA-API.txt
DMA-attributes.txt
dma-buf-sharing.txt
DMA-ISA-LPC.txt
dontdiff
dynamic-debug-howto.txt
edac.txt
efi-stub.txt
eisa.txt
email-clients.txt
flexible-arrays.txt
futex-requeue-pi.txt	doc: Fix misnamed FUTEX_CMP_REQUEUE_PI op constants	2015-01-19 12:05:32 +01:00
gcov.txt
gdb-kernel-debugging.txt	scripts/gdb: add basic documentation	2015-02-17 14:34:54 -08:00
highuid.txt
HOWTO
hsi.txt
hw_random.txt
hwspinlock.txt
init.txt
initrd.txt
Intel-IOMMU.txt
intel_txt.txt
io-mapping.txt
io_ordering.txt
iostats.txt
IPMI.txt
IRQ-affinity.txt
IRQ-domain.txt
IRQ.txt
irqflags-tracing.txt
isapnp.txt
java.txt
kasan.txt	kasan: enable instrumentation of global variables	2015-02-13 21:21:42 -08:00
kernel-doc-nano-HOWTO.txt
kernel-docs.txt
kernel-parameters.txt	watchdog: enable the new user interface of the watchdog mechanism	2015-04-14 16:48:59 -07:00
kernel-per-CPU-kthreads.txt
kmemcheck.txt
kmemleak.txt
kobject.txt
kprobes.txt	Documentation: add description for FTRACE probe status	2015-02-04 16:05:44 -05:00
kref.txt
kselftest.txt
ldm.txt
local_ops.txt
lockup-watchdogs.txt
logo.gif
logo.txt
lzo.txt
magic-number.txt
mailbox.txt
Makefile
ManagementStyle
md.txt
media-framework.txt
memory-barriers.txt	documentation: Fix smp typo in memory-barriers.txt	2015-01-07 08:59:32 -08:00
memory-hotplug.txt
module-signing.txt
mono.txt
nommu-mmap.txt	fs: introduce f_op->mmap_capabilities for nommu mmap support	2015-01-20 14:02:58 -07:00
numastat.txt
oops-tracing.txt	livepatch: kernel: add TAINT_LIVEPATCH	2014-12-22 15:40:48 +01:00
padata.txt
parport-lowlevel.txt
parport.txt
percpu-rw-semaphore.txt
phy.txt
pi-futex.txt
pinctrl.txt
pnp.txt
preempt-locking.txt
printk-formats.txt
pwm.txt
ramoops.txt
rbtree.txt
remoteproc.txt
rfkill.txt	rfkill: document rfkill module parameters	2015-01-09 23:22:12 +01:00
robust-futex-ABI.txt
robust-futexes.txt
rpmsg.txt
rtc.txt	Documentation, split up rtc.txt into documentation and test file	2015-03-24 22:01:58 -06:00
SAK.txt
SecurityBugs
serial-console.txt
sgi-ioc4.txt
SM501.txt
smsc_ece1099.txt
sparse.txt
stable_api_nonsense.txt
stable_kernel_rules.txt	stable_kernel_rules: Add clause about specification of kernel versions to patch.	2015-03-26 23:52:24 +01:00
static-keys.txt
SubmitChecklist
SubmittingDrivers
SubmittingPatches	Merge branch 'doc/sp-update' into docs-next	2015-01-29 13:11:58 -07:00
svga.txt
sysfs-rules.txt
sysrq.txt
this_cpu_ops.txt
unaligned-memory-access.txt
unicode.txt
unshare.txt
vfio.txt
VGA-softcursor.txt
vgaarbiter.txt
video-output.txt
vme_api.txt
volatile-considered-harmful.txt
workqueue.txt
xillybus.txt
xz.txt
zorro.txt