commit 5b39939a4 (nohz: Move ts->idle_calls incrementation into strict
idle logic) moved code out of tick_nohz_stop_sched_tick() and missed
to bail out when the cpu is offline. That's causing subsequent
failures as an offline CPU is supposed to die and not to fiddle with
nohz magic.
Return false in can_stop_idle_tick() if the cpu is offline.
Reported-and-tested-by: Jiri Kosina <jkosina@suse.cz>
Reported-and-tested-by: Prarit Bhargava <prarit@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1305132138160.2863@ionos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
As per commit 764e0da1 (timers: Fixup the Kconfig consolidation
fallout), init/Kconfig already includes kernel/time/Kconfig, so no need
to do it explicitly for arm64.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The format of the lower 32-bits of the 64-bit operand to 'dc cisw' is
unchanged from ARMv7 architecture and the upper bits are RES0. This
implies that the 'way' field of the operand of 'dc cisw' occupies the
bit-positions [31 .. (32-A)]. Due to the use of 64-bit extended operands
to 'clz', the existing implementation of __flush_dcache_all is incorrectly
placing the 'way' field in the bit-positions [63 .. (64-A)].
Signed-off-by: Sukanto Ghosh <sghosh@apm.com>
Tested-by: Anup Patel <anup.patel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: stable@vger.kernel.org
The of_platform_populate() is currently invoked at device_initcall()
level. There are however drivers that use platform_driver_probe()
directly and they need the devices to be populated. This patch makes the
of_platform_populate() and arch_initcall().
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Benoit Lecardonnel <Benoit.Lecardonnel@synopsys.com>
Tested-by: Benoit Lecardonnel <Benoit.Lecardonnel@synopsys.com>
Pull powerpc fixes from Benjamin Herrenschmidt:
"This is mostly bug fixes (some of them regressions, some of them I
deemed worth merging now) along with some patches from Li Zhong
hooking up the new context tracking stuff (for the new full NO_HZ)"
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (25 commits)
powerpc: Set show_unhandled_signals to 1 by default
powerpc/perf: Fix setting of "to" addresses for BHRB
powerpc/pmu: Fix order of interpreting BHRB target entries
powerpc/perf: Move BHRB code into CONFIG_PPC64 region
powerpc: select HAVE_CONTEXT_TRACKING for pSeries
powerpc: Use the new schedule_user API on userspace preemption
powerpc: Exit user context on notify resume
powerpc: Exception hooks for context tracking subsystem
powerpc: Syscall hooks for context tracking subsystem
powerpc/booke64: Fix kernel hangs at kernel_dbg_exc
powerpc: Fix irq_set_affinity() return values
powerpc: Provide __bswapdi2
powerpc/powernv: Fix starting of secondary CPUs on OPALv2 and v3
powerpc/powernv: Detect OPAL v3 API version
powerpc: Fix MAX_STACK_TRACE_ENTRIES too low warning again
powerpc: Make CONFIG_RTAS_PROC depend on CONFIG_PROC_FS
powerpc: Bring all threads online prior to migration/hibernation
powerpc/rtas_flash: Fix validate_flash buffer overflow issue
powerpc/kexec: Fix kexec when using VMX optimised memcpy
powerpc: Fix build errors STRICT_MM_TYPECHECKS
...
* acpi-fixes:
ACPI / AC: Add sleep quirk for Thinkpad e530
ACPI / EC: Restart transaction even when the IBF flag set
ACPI video: ignore BIOS initial backlight value for HP 1000
ACPI: Fix section to __init. Align with usage in acpixf.h
ACPI / PM: Move processor suspend/resume to syscore_ops
* pm-cpufreq:
cpufreq / intel_pstate: use vzalloc() instead of vmalloc()/memset(0)
cpufreq, ondemand: Remove leftover debug line
cpufreq / kirkwood: don't check resource with devm_ioremap_resource
cpufreq / intel_pstate: remove #ifdef MODULE compile fence
cpufreq / intel_pstate: Remove idle mode PID
cpufreq / intel_pstate: fix ffmpeg regression
cpufreq / intel_pstate: use lowest requested max performance
cpufreq / intel_pstate: remove idle time and duration from sample and calculations
cpufreq: Fix incorrect dependecies for ARM SA11xx drivers
cpufreq: ARM big LITTLE: Fix Kconfig entries
cpufreq: cpufreq-cpu0: Free parent node for error cases
cpufreq: cpufreq-cpu0: defer probe when regulator is not ready
cpufreq: Issue CPUFREQ_GOV_POLICY_EXIT notifier before dropping policy refcount
cpufreq: governors: Fix CPUFREQ_GOV_POLICY_{INIT|EXIT} notifiers
cpufreq: ARM big LITTLE: Improve print message
cpufreq: ARM big LITTLE: Move cpu_to_cluster() to arm_big_little.h
cpufreq: ARM big LITTLE DT: Return CPUFREQ_ETERNAL if clock-latency isn't found
cpufreq: ARM big LITTLE DT: Return correct transition latency
cpufreq: ARM big LITTLE: Select PM_OPP
Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.
Introduced by commit 9dddb4df90
(pinctrl: single: support generic pinconf)
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
WMT_PIN_WAKEUP1 should be declared as WMT_PIN(0, 17) rather than
WMT_PIN(0, 16). This currently generates a runtime warning because
WMT_PIN_WAKEUP0 is already defined as WMT_PIN(0, 16).
Signed-off-by: Tony Prisk <linux@prisktech.co.nz>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Platform Data is invariably populated for this driver, even when
booting with Device Tree. Thus the Device Tree probing code encased
within the first check for Platform Data will never executed, causing
the driver to fail when DT is enabled.
This patch fixes the aforementioned regression by rejigging the
probe() semantics to attempt to extract a platform ID from Device Tree
if one can not be sourced from platform data.
A pointer to GPIO platform data is always passed to the driver now, so
there's little point in checking for 'pdata' and executing the DT case if
it's not there. The difference between booting with DT and !DT is when
booting with DT, plat_id is not populated. Thus, in the DT case we have
to use a DT match table in order to find out which platform we're
executing on. So, we're changing the semantics here to only use the
match table if no plat_id is supplied though platform data.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
[edited commit message]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
If a sub-driver has not been specified correctly, there is a good chance
that plat_id is NULL, hence using an attribute of plat_id in the error
message is likely to not only fail the driver but Oops the kernel. Use
the failed ID instead.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Currently we only set the "to" address in the branch stack when the CPU
explicitly gives us a value. Unfortunately it only does this for XL form
branches (eg blr, bctr, bctar) and not I and B form branches (eg b, bc).
Fortunately if we read the instruction from memory we can extract the offset of
a branch and calculate the target address.
This adds a function power_pmu_bhrb_to() to calculate the target/to address of
the corresponding I and B form branches. It handles branches in both user and
kernel spaces. It also plumbs this into the perf brhb reading code.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The current Branch History Rolling Buffer (BHRB) code misinterprets the order
of entries in the hardware buffer. It assumes that a branch target address
will be read _after_ its corresponding branch. In reality the branch target
comes before (lower mfbhrb entry) it's corresponding branch.
This is a rewrite of the code to take this into account.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The new Branch History Rolling buffer (BHRB) code is only useful on 64bit
processors, so move it into the #ifdef CONFIG_PPC64 region.
This avoids code bloat on 32bit systems.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Start context tracking support from pSeries.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch corresponds to
[PATCH] x86: Use the new schedule_user API on userspace preemption
commit 0430499ce9
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch allows RCU usage in do_notify_resume, e.g. signal handling.
It corresponds to
[PATCH] x86: Exit RCU extended QS on notify resume
commit edf55fda35
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This is the exception hooks for context tracking subsystem, including
data access, program check, single step, instruction breakpoint, machine check,
alignment, fp unavailable, altivec assist, unknown exception, whose handlers
might use RCU.
This patch corresponds to
[PATCH] x86: Exception hooks for userspace RCU extended QS
commit 6ba3c97a38
But after the exception handling moved to generic code, and some changes in
following two commits:
56dd9470d7
context_tracking: Move exception handling to generic code
6c1e0256fa
context_tracking: Restore correct previous context state on exception exit
it is able for exception hooks to use the generic code above instead of a
redundant arch implementation.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This is the syscall slow path hooks for context tracking subsystem,
corresponding to
[PATCH] x86: Syscall hooks for userspace RCU extended QS
commit bf5a3c13b9
TIF_MEMDIE is moved to the second 16-bits (with value 17), as it seems there
is no asm code using it. TIF_NOHZ is added to _TIF_SYCALL_T_OR_A, so it is
better for it to be in the same 16 bits with others in the group, so in the
asm code, andi. with this group could work.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
MSR_DE is not cleared on entry to the kernel, and we don't clear it
explicitly outside of debug code. If we have MSR_DE set in
prime_debug_regs(), and the new thread has events enabled in DBCR0
(e.g. ICMP is set in thread->dbsr0, even though it was cleared in the
real DBCR0 when the thread got scheduled out), we'll end up taking a
debug exception in the kernel when DBCR0 is loaded. DSRR0 will not
point to an exception vector, and the kernel ends up hanging at
kernel_dbg_exc. Fix this by always clearing MSR_DE when we load new
debug state.
Another observed source of kernel_dbg_exc hangs is with the branch
taken event. If this event is active, but we take a non-debug trap
(e.g. a TLB miss or an asynchronous interrupt) before the next branch.
We end up taking a branch-taken debug exception on the initial branch
instruction of the exception vector, but because the debug exception is
DBSR_BT rather than DBSR_IC we branch to kernel_dbg_exc before even
checking the DSRR0 address. Fix this by checking for DBSR_BT as well
as DBSR_IC, which is what 32-bit does and what the comments suggest was
intended in the 64-bit code as well.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Some versions of GCC apparently expect this to be provided by libgcc.
Updates from Mikey to fix 32 bit version and adding "r" to registers.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The current code fails to handle kexec on OPALv2. This fixes it
and adds code to improve the situation on OPALv3 where we can
query the CPU status from the firmware and decide what to do
based on that.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Saw this warning again, and this time from the ret_from_fork path.
It seems we could clear the back chain earlier in copy_thread(), which
could cover both path, and also fix potential lockdep usage in
schedule_tail(), or exception occurred before we clear the back chain.
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We are getting build errors with CONFIG_PROC_FS=n:
arch/powerpc/kernel/rtas_flash.c
In function 'rtas_flash_init':
745:33: error: unused variable 'f' [-Werror=unused-variable]
But rtas_flash.c should not be built when CONFIG_PROC_FS=n, beacause all
it does is provide a /proc interface to the RTAS flash routines.
CONFIG_RTAS_FLASH already depends on CONFIG_RTAS_PROC, to indicate that
it depends on the RTAS proc support, but CONFIG_RTAS_PROC does not
depend on CONFIG_PROC_FS. So fix that.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch brings online all threads which are present but not online
prior to migration/hibernation. After migration/hibernation those
threads are taken back offline.
During migration/hibernation all online CPUs must call H_JOIN, this is
required by the hypervisor. Without this patch, threads that are offline
(H_CEDE'd) will not be woken to make the H_JOIN call and the OS will be
deadlocked (all threads either JOIN'd or CEDE'd).
Cc: <stable@kernel.org>
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
commit b3f271e86e (powerpc: POWER7 optimised memcpy using VMX and
enhanced prefetch) uses VMX when it is safe to do so (ie not in
interrupt). It also looks at the task struct to decide if we have to
save the current tasks' VMX state.
kexec calls memcpy() at a point where the task struct may have been
overwritten by the new kexec segments. If it has been overwritten
then when memcpy -> enable_altivec looks up current->thread.regs->msr
we get a cryptic oops or lockup.
I also notice we aren't initialising thread_info->cpu, which means
smp_processor_id is broken. Fix that too.
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: <stable@vger.kernel.org> # 3.6+
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Our pgtable are 2*sizeof(pte_t)*PTRS_PER_PTE which is PTE_FRAG_SIZE.
Instead of depending on frag size, mask with PMD_MASKED_BITS.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Merge tag 'fixes-for-3.10-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/sstabellini/xen
Pull Xen/arm fixes from Stefano Stabellini:
"This contains a couple of Xen on ARM initialization fixes and a patch
to improve error handling"
* tag 'fixes-for-3.10-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/sstabellini/xen:
xen/arm: rename xen_secondary_init and run it on every online cpu
xen/arm: do not handle VCPUOP_register_vcpu_info failures
xen/arm: initialize pm functions later
Correct the meaning of PM_HIBERNATION_PREPARE in the docs.
References: http://lkml.kernel.org/r/20130512162717.GA6305@pd.tnic
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull parisc update from Helge Deller:
"The second round of parisc updates for 3.10 includes build fixes and
enhancements to utilize irq stacks, fixes SMP races when updating PTE
and TLB entries by proper locking and makes the search for the correct
cross compiler more robust on Debian and Gentoo."
* 'parisc-for-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: make default cross compiler search more robust (v3)
parisc: fix SMP races when updating PTE and TLB entries in entry.S
parisc: implement irq stacks - part 2 (v2)
The lantency of the transition from suspend and hibernate is
platform-dependent. Thus we should not refer the lantency in the
documentation.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Use vzalloc() instead of vmalloc() and memset(0).
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Dirk Brandewie <dirk.j.brandewie@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The implementation of cmpxchg64() for the ARM v6 and v7 architecture
casts parameter 2 and 3 (the old and new 64bit values) to an unsigned
long before calling the atomic_cmpxchg64() function. This clears
the top 32 bits of the old and new values, resulting in the wrong
values being compare-exchanged. Luckily, this only appears to be used
for 64-bit sched_clock, which we don't (yet) have on ARM.
This bug was introduced by commit 3e0f5a15f5 ("ARM: 7404/1: cmpxchg64:
use atomic64 and local64 routines for cmpxchg64").
Cc: <stable@vger.kernel.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jaccon Bastiaansen <jaccon.bastiaansen@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull networking fixes from David Miller:
"Several small bug fixes all over:
1) be2net driver uses wrong payload length when submitting MAC list
get requests to the chip. From Sathya Perla.
2) Fix mwifiex memory leak on driver unload, from Amitkumar Karwar.
3) Prevent random memory access in batman-adv, from Marek Lindner.
4) batman-adv doesn't check for pskb_trim_rcsum() errors, also from
Marek Lindner.
5) Fix fec crashes on rapid link up/down, from Frank Li.
6) Fix inner protocol grovelling in GSO, from Pravin B Shelar.
7) Link event validation fix in qlcnic from Rajesh Borundia.
8) Not all FEC chips can support checksum offload, fix from Shawn
Guo.
9) EXPORT_SYMBOL + inline doesn't make any sense, from Denis Efremov.
10) Fix race in passthru mode during device removal in macvlan, from
Jiri Pirko.
11) Fix RCU hash table lookup socket state race in ipv6, leading to
NULL pointer derefs, from Eric Dumazet.
12) Add several missing HAS_DMA kconfig dependencies, from Geert
Uyttterhoeven.
13) Fix bogus PCI resource management in 3c59x driver, from Sergei
Shtylyov.
14) Fix info leak in ipv6 GRE tunnel driver, from Amerigo Wang.
15) Fix device leak in ipv6 IPSEC policy layer, from Cong Wang.
16) DMA mapping leak fix in qlge from Thadeu Lima de Souza Cascardo.
17) Missing iounmap on probe failure in bna driver, from Wei Yongjun."
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (40 commits)
bna: add missing iounmap() on error in bnad_init()
qlge: fix dma map leak when the last chunk is not allocated
xfrm6: release dev before returning error
ipv6,gre: do not leak info to user-space
virtio_net: use default napi weight by default
emac: Fix EMAC soft reset on 460EX/GT
3c59x: fix PCI resource management
caif: CAIF_VIRTIO should depend on HAS_DMA
net/ethernet: MACB should depend on HAS_DMA
net/ethernet: ARM_AT91_ETHER should depend on HAS_DMA
net/wireless: ATH9K should depend on HAS_DMA
net/ethernet: STMMAC_ETH should depend on HAS_DMA
net/ethernet: NET_CALXEDA_XGMAC should depend on HAS_DMA
ipv6: do not clear pinet6 field
macvlan: fix passthru mode race between dev removal and rx path
ipv4: ip_output: remove inline marking of EXPORT_SYMBOL functions
net/mlx4: Strengthen VLAN tags/priorities enforcement in VST mode
net/mlx4_core: Add missing report on VST and spoof-checking dev caps
net: fec: enable hardware checksum only on imx6q-fec
qlcnic: Fix validation of link event command.
...
People/distros vary how they prefix the toolchain name for 64bit builds.
Rather than enforce one convention over another, add a for loop which
does a search for all the general prefixes.
For 64bit builds, we now search for (in order):
hppa64-unknown-linux-gnu
hppa64-linux-gnu
hppa64-linux
For 32bit builds, we look for:
hppa-unknown-linux-gnu
hppa-linux-gnu
hppa-linux
hppa2.0-unknown-linux-gnu
hppa2.0-linux-gnu
hppa2.0-linux
hppa1.1-unknown-linux-gnu
hppa1.1-linux-gnu
hppa1.1-linux
This patch was initiated by Mike Frysinger, with feedback from Jeroen
Roovers, John David Anglin and Helge Deller.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Jeroen Roovers <jer@gentoo.org>
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Add code to rbd_img_obj_exists_callback() to detect when a clone's
parent image has disappeared, and re-submit the original write
request in that case.
Kill off some redundant assertions.
This completes the resolution for:
http://tracker.ceph.com/issues/3763
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Add code to rbd_img_parent_read_full_callback() to detect when a
clone's parent image has disappeared, and re-submit the original
write request in that case. (See the previous commit for more
reasoning about why this is appropriate.)
Rename some variables in rbd_img_obj_parent_read_full_callback()
to match the convention used in the previous patch.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
If a clone image gets flattened while a parent read request is
underway, the original rbd object request needs to be resubmitted.
The reason is that by the time we get the response to the parent
read request, the data read from the parent may be out of date.
In other words, we could see this sequence of events:
rbd client parent image/osd
---------- ----------------
original object ENOENT;
issue parent read
respond to parent read
child image flattened
original image header refresh
<--- original object written independently here
parent read response received
Add code to rbd_img_parent_read_callback() to detect when a clone's
parent image has disappeared (as evidenced by its parent overlap
becoming 0), and re-submit the original read request in that case.
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
A format 2 clone image can be the subject of a "flatten" operation,
during which all of its data gets "copied up" from its parent image,
leaving the image fully populated. Once this is complete, the
clone's association with the parent is abolished.
Since this can occur when a clone is mapped, we need to detect when
it has occurred and handle it accordingly. We know an image has
been flattened when we know it at one time had a parent, but we have
learned (via a "get_parent" object class method call) it no longer
has one.
There might be in-flight requests at the point we learn an image has
been flattened, so we can't simply clean up parent data structures
right away. Instead, we'll drop the initial parent reference when
the parent has disappeared (rather than when the image gets
destroyed), which will allow the last in-flight reference to clean
things up when it's complete.
We leverage the fact that a zero parent overlap renders an image
effectively unlayered. We set the overlap to 0 at the point we
detect the clone image has flattened, which allows the unlayered
behavior to take effect immediately, while keeping other parent
structures in place until in-flight requests to complete.
This and the next few patches resolve:
http://tracker.ceph.com/issues/3763
Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
