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573,810 commits

Author SHA1 Message Date
Christoph Biedl
19cebbcb04 isdn: Partially revert debug format string usage clean up
Commit 35a4a57 ("isdn: clean up debug format string usage") introduced
a safeguard to avoid accidential format string interpolation of data
when calling debugl1 or HiSax_putstatus. This did however not take into
account VHiSax_putstatus (called by HiSax_putstatus) does *not* call
vsprintf if the head parameter is NULL - the format string is treated
as plain text then instead. As a result, the string "%s" is processed
literally, and the actual information is lost. This affects the isdnlog
userspace program which stopped logging information since that commit.

So revert the HiSax_putstatus invocations to the previous state.

Fixes: 35a4a5733b ("isdn: clean up debug format string usage")
Cc: Kees Cook <keescook@chromium.org>
Cc: Karsten Keil <isdn@linux-pingi.de>
Signed-off-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-25 11:49:58 -05:00
Benjamin Romer
f84a187019 staging: unisys: better config switch comments
We should provide more information in the Kconfig help for visorbus and
visorinput.

Signed-off-by: Benjamin Romer <benjamin.romer@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-11-25 08:42:14 -08:00
Anjali Menon
24069d287c staging: unisys: visornic: Removed the blank line
Removed the blank line before the close brace to remove the check
detected by the checkpatch.pl

CHECK: Blank lines aren't necessary before a close brace '}'

Signed-off-by: Anjali Menon <cse.anjalimenon@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-11-25 08:42:14 -08:00
Shraddha Barke
f2fd578f16 Staging: lustre: obd_cksum.h: Remove unused cksum_types_supported_server
cksum_types_supported_server is defined in header file but not used
anywhere. Hence remove it.

Signed-off-by: Shraddha Barke <shraddha.6596@gmail.com>
Acked-by: James Simmons <jsimmons@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-11-25 08:39:07 -08:00
Florian Fainelli
9458ceab49 net: phy: bcm7xxx: Add entry for Broadcom BCM7435
Add a PHY entry for the Broadcom BCM7435 chips, this is a 40nm
generation Ethernet PHY which is analogous to its 7425 and 7429 counter
parts.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-25 11:35:14 -05:00
Alex Deucher
9c565e3386 drm/radeon: make some dpm errors debug only
"Could not force DPM to low", etc. is usually harmless and
just confuses users.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2015-11-25 11:28:42 -05:00
Takuya Yoshikawa
4700579241 KVM: x86: MMU: Move initialization of parent_ptes out from kvm_mmu_alloc_page()
Make kvm_mmu_alloc_page() do just what its name tells to do, and remove
the extra allocation error check and zero-initialization of parent_ptes:
shadow page headers allocated by kmem_cache_zalloc() are always in the
per-VCPU pools.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:27:06 +01:00
Takuya Yoshikawa
77fbbbd2f0 KVM: x86: MMU: Consolidate BUG_ON checks for reverse-mapped sptes
At some call sites of rmap_get_first() and rmap_get_next(), BUG_ON is
placed right after the call to detect unrelated sptes which must not be
found in the reverse-mapping list.

Move this check in rmap_get_first/next() so that all call sites, not
just the users of the for_each_rmap_spte() macro, will be checked the
same way.

One thing to keep in mind is that kvm_mmu_unlink_parents() also uses
rmap_get_first() to handle parent sptes.  The change will not break it
because parent sptes are present, at least until drop_parent_pte()
actually unlinks them, and not mmio-sptes.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:26:47 +01:00
Takuya Yoshikawa
afd28fe1c9 KVM: x86: MMU: Remove is_rmap_spte() and use is_shadow_present_pte()
is_rmap_spte(), originally named is_rmap_pte(), was introduced when the
simple reverse mapping was implemented by commit cd4a4e5374
("[PATCH] KVM: MMU: Implement simple reverse mapping").  At that point,
its role was clear and only rmap_add() and rmap_remove() were using it
to select sptes that need to be reverse-mapped.

Independently of that, is_shadow_present_pte() was first introduced by
commit c7addb9020 ("KVM: Allow not-present guest page faults to
bypass kvm") to do bypass_guest_pf optimization, which does not exist
any more.

These two seem to have changed their roles somewhat, and is_rmap_spte()
just calls is_shadow_present_pte() now.

Since using both of them without clear distinction just makes the code
confusing, remove is_rmap_spte().

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:26:35 +01:00
Takuya Yoshikawa
029499b477 KVM: x86: MMU: Make mmu_set_spte() return emulate value
mmu_set_spte()'s code is based on the assumption that the emulate
parameter has a valid pointer value if set_spte() returns true and
write_fault is not zero.  In other cases, emulate may be NULL, so a
NULL-check is needed.

Stop passing emulate pointer and make mmu_set_spte() return the emulate
value instead to clean up this complex interface.  Prefetch functions
can just throw away the return value.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:26:28 +01:00
Takuya Yoshikawa
fd9514572f KVM: x86: MMU: Add helper function to clear a bit in unsync child bitmap
Both __mmu_unsync_walk() and mmu_pages_clear_parents() have three line
code which clears a bit in the unsync child bitmap; the former places it
inside a loop block and uses a few goto statements to jump to it.

A new helper function, clear_unsync_child_bit(), makes the code cleaner.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:26:15 +01:00
Takuya Yoshikawa
7ee0e5b29d KVM: x86: MMU: Remove unused parameter of __direct_map()
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:26:03 +01:00
Takuya Yoshikawa
018aabb56d KVM: x86: MMU: Encapsulate the type of rmap-chain head in a new struct
New struct kvm_rmap_head makes the code type-safe to some extent.

Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:25:44 +01:00
Yaowei Bai
378b417d65 KVM: powerpc: kvmppc_visible_gpa can be boolean
In another patch kvm_is_visible_gfn is maken return bool due to this
function only returns zero or one as its return value, let's also make
kvmppc_visible_gpa return bool to keep consistent.

No functional change.

Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:24 +01:00
Yaowei Bai
08ff0d5e63 KVM: kvm_para_has_feature can be boolean
This patch makes kvm_para_has_feature return bool due to this
particular function only using either one or zero as its return
value.

No functional change.

Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:23 +01:00
Yaowei Bai
33e9415479 KVM: kvm_is_visible_gfn can be boolean
This patch makes kvm_is_visible_gfn return bool due to this particular
function only using either one or zero as its return value.

No functional change.

Signed-off-by: Yaowei Bai <baiyaowei@cmss.chinamobile.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:23 +01:00
Markus Elfring
4f52696a6c KVM-async_pf: Delete an unnecessary check before the function call "kmem_cache_destroy"
The kmem_cache_destroy() function tests whether its argument is NULL
and then returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:23 +01:00
Paolo Bonzini
0e3d0648bd KVM: x86: MMU: always set accessed bit in shadow PTEs
Commit 7a1638ce42 ("nEPT: Redefine EPT-specific link_shadow_page()",
2013-08-05) says:

    Since nEPT doesn't support A/D bit, we should not set those bit
    when building the shadow page table.

but this is not necessary.  Even though nEPT doesn't support A/D
bits, and hence the vmcs12 EPT pointer will never enable them,
we always use them for shadow page tables if available (see
construct_eptp in vmx.c).  So we can set the A/D bits freely
in the shadow page table.

This patch hence basically reverts commit 7a1638ce42.

Cc: Yang Zhang <yang.z.zhang@Intel.com>
Cc: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:23 +01:00
Paolo Bonzini
aba2f06c07 KVM: x86: correctly print #AC in traces
Poor #AC was so unimportant until a few days ago that we were
not even tracing its name correctly.  But now it's all over
the place.

Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:23 +01:00
Paolo Bonzini
46896c73c1 KVM: svm: add support for RDTSCP
RDTSCP was never supported for AMD CPUs, which nobody noticed because
Linux does not use it.  But exactly the fact that Linux does not
use it makes the implementation very simple; we can freely trash
MSR_TSC_AUX while running the guest.

Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:22 +01:00
Paolo Bonzini
9dbe6cf941 KVM: x86: expose MSR_TSC_AUX to userspace
If we do not do this, it is not properly saved and restored across
migration.  Windows notices due to its self-protection mechanisms,
and is very upset about it (blue screen of death).

Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:22 +01:00
Andrey Smetanin
db3975717a kvm/x86: Hyper-V kvm exit
A new vcpu exit is introduced to notify the userspace of the
changes in Hyper-V SynIC configuration triggered by guest writing to the
corresponding MSRs.

Changes v4:
* exit into userspace only if guest writes into SynIC MSR's

Changes v3:
* added KVM_EXIT_HYPERV types and structs notes into docs

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:22 +01:00
Andrey Smetanin
5c919412fe kvm/x86: Hyper-V synthetic interrupt controller
SynIC (synthetic interrupt controller) is a lapic extension,
which is controlled via MSRs and maintains for each vCPU
 - 16 synthetic interrupt "lines" (SINT's); each can be configured to
   trigger a specific interrupt vector optionally with auto-EOI
   semantics
 - a message page in the guest memory with 16 256-byte per-SINT message
   slots
 - an event flag page in the guest memory with 16 2048-bit per-SINT
   event flag areas

The host triggers a SINT whenever it delivers a new message to the
corresponding slot or flips an event flag bit in the corresponding area.
The guest informs the host that it can try delivering a message by
explicitly asserting EOI in lapic or writing to End-Of-Message (EOM)
MSR.

The userspace (qemu) triggers interrupts and receives EOM notifications
via irqfd with resampler; for that, a GSI is allocated for each
configured SINT, and irq_routing api is extended to support GSI-SINT
mapping.

Changes v4:
* added activation of SynIC by vcpu KVM_ENABLE_CAP
* added per SynIC active flag
* added deactivation of APICv upon SynIC activation

Changes v3:
* added KVM_CAP_HYPERV_SYNIC and KVM_IRQ_ROUTING_HV_SINT notes into
docs

Changes v2:
* do not use posted interrupts for Hyper-V SynIC AutoEOI vectors
* add Hyper-V SynIC vectors into EOI exit bitmap
* Hyper-V SyniIC SINT msr write logic simplified

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:22 +01:00
Andrey Smetanin
d62caabb41 kvm/x86: per-vcpu apicv deactivation support
The decision on whether to use hardware APIC virtualization used to be
taken globally, based on the availability of the feature in the CPU
and the value of a module parameter.

However, under certain circumstances we want to control it on per-vcpu
basis.  In particular, when the userspace activates HyperV synthetic
interrupt controller (SynIC), APICv has to be disabled as it's
incompatible with SynIC auto-EOI behavior.

To achieve that, introduce 'apicv_active' flag on struct
kvm_vcpu_arch, and kvm_vcpu_deactivate_apicv() function to turn APICv
off.  The flag is initialized based on the module parameter and CPU
capability, and consulted whenever an APICv-specific action is
performed.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:21 +01:00
Andrey Smetanin
6308630bd3 kvm/x86: split ioapic-handled and EOI exit bitmaps
The function to determine if the vector is handled by ioapic used to
rely on the fact that only ioapic-handled vectors were set up to
cause vmexits when virtual apic was in use.

We're going to break this assumption when introducing Hyper-V
synthetic interrupts: they may need to cause vmexits too.

To achieve that, introduce a new bitmap dedicated specifically for
ioapic-handled vectors, and populate EOI exit bitmap from it for now.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:21 +01:00
Andrey Smetanin
abdb080f7a kvm/irqchip: kvm_arch_irq_routing_update renaming split
Actually kvm_arch_irq_routing_update() should be
kvm_arch_post_irq_routing_update() as it's called at the end
of irq routing update.

This renaming frees kvm_arch_irq_routing_update function name.
kvm_arch_irq_routing_update() weak function which will be used
to update mappings for arch-specific irq routing entries
(in particular, the upcoming Hyper-V synthetic interrupts).

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:21 +01:00
Lars Ellenberg
8011e24909 drbd: fix error path during resize
In case the lower level device size changed, but some other internal
details of the resize did not work out, drbd_determine_dev_size() would
try to restore the previous settings, trusting
drbd_md_set_sector_offsets() to "do the right thing", but overlooked
that this internally may set the meta data base offset based on device size.

This could end up with incomplete on-disk meta data layout change, and
ultimately lead to data corruption (if the failure was not noticed or
ignored by the operator, and other things go wrong as well).

Just remember all meta data related offsets/sizes,
and on error restore them all.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:03 -07:00
Lars Ellenberg
5f7c01249b drbd: avoid potential deadlock during handshake
During handshake communication, we also reconsider our device size,
using drbd_determine_dev_size(). Just in case we need to change the
offsets or layout of our on-disk metadata, we lock out application
and other meta data IO, and wait for the activity log to be "idle"
(no more referenced extents).

If this handshake happens just after a connection loss, with a fencing
policy of "resource-and-stonith", we have frozen IO.

If, additionally, the activity log was "starving" (too many incoming
random writes at that point in time), it won't become idle, ever,
because of the frozen IO, and this would be a lockup of the receiver
thread, and consquentially of DRBD.

Previous logic (re-)initialized with a special "empty" transaction
block, which required the activity log to fully drain first.

Instead, write out some standard activity log transactions.
Using lc_try_lock_for_transaction() instead of lc_try_lock() does not
care about pending activity log references, avoiding the potential
deadlock.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:03 -07:00
Lars Ellenberg
603ee2c8c7 drbd: separate out __al_write_transaction helper function
To be able to "force out" an activity log transaction,
even if there are no pending updates.

This will be used to relocate the on-disk activity log,
if the on-disk offsets have to be changed,
without the need to empty the activity log first.

While at it, move the definition,
so we can drop the forward declaration of a static helper.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:03 -07:00
Philipp Reisner
7dbb4386b9 drbd: make suspend_io() / resume_io() must be thread and recursion safe
Avoid to prematurely resume application IO: don't set/clear a single
bit, but inc/dec an atomic counter.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:03 -07:00
Lars Ellenberg
f85d9f2d02 drbd: fix "endless" transfer log walk in protocol A
Don't remember a DRBD request as ack_pending, if it is not.

In protocol A, we usually clear RQ_NET_PENDING at the same time we set
RQ_NET_SENT, so when deciding to remember it as ack_pending,
mod_rq_state needs to look at the current request state,
not at the previous state before the current modification was applied.

This should prevent advance_conn_req_ack_pending() from walking the full
transfer log just to find NULL in protocol A, which would cause serious
performance degradation with many "in-flight" requests, e.g. when
working via DRBD-proxy, or with a huge bandwidth-delay product.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:03 -07:00
Oleg Drokin
706447861b drbd: fix memory leak in drbd_adm_resize
new_disk_conf could be leaked if the follow on checks fail,
so make sure to free it on error if it was not assigned yet.

Found with smatch.

Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:03 -07:00
Lars Ellenberg
5bded4effb drbd: don't block forever in disconnect during resync if fencing=r-a-stonith
Disconnect should wait for pending bitmap IO.
But if that bitmap IO is not happening, because it is waiting for
pending application IO, and there is no progress, because the fencing
policy suspended application IO because of the disconnect,
then we deadlock.

The bitmap writeout in this case does not care for concurrent
application IO, so there is no point waiting for it.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:02 -07:00
Roland Kammerer
bb649b34dd lru_cache: Converted lc_seq_printf_status to return void
Fix the semantic of lc_seq_printf. Currently, it always returns 0 and
the return value is unused, therefore, convert the return type to void.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:02 -07:00
Lars Ellenberg
63a7c8ad92 drbd: make drbd known to lsblk: use bd_link_disk_holder
lsblk should be able to pick up stacking device driver relations
involving DRBD conveniently.

Even though upstream kernel since 2011 says
	"DON'T USE THIS UNLESS YOU'RE ALREADY USING IT."
a new user has been added since (bcache),
which sets the precedences for us to use it as well.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:02 -07:00
Lars Ellenberg
088b70526d drbd: fix queue limit setup for discard
We cannot possibly support SECDISCARD, even if all backend devices would
support it: if our peer is currently unreachable, some instance of the
data may obviously still be recoverable.

We did not set discard_granularity at all.  We don't really care (yet),
we only pass them on, so for now, set our granularity to one sector.
blkdev_stack_limits() takes care of the rest.

If we decide we cannot support discards,
not only clear the (not user visible) QUEUE_FLAG_DISCARD,
but set both (user visible) discard_granularity and max_discard_sectors
to zero, to avoid confusion with e.g. lsblk -D.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:02 -07:00
Lars Ellenberg
edb5e5f63d drbd: fix spurious alert level printk
When accessing out meta data area on disk, we double check the
plausibility of the requested sector offsets, and are very noisy about
it if they look suspicious.

During initial read of our "superblock", for "external" meta data,
this triggered because the range estimate returned by
drbd_md_last_sector() was still wrong.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:02 -07:00
Lars Ellenberg
5fb3bc4ddc drbd: use bitmap_weight() helper, don't open code
Suggested by Akinobu Mita <akinobu.mita@gmail.com>

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:02 -07:00
Lars Ellenberg
2630628b2d drbd: avoid redefinition of BITS_PER_PAGE
Apparently we now implicitly get definitions for BITS_PER_PAGE and
BITS_PER_PAGE_MASK from the pid_namespace.h

Instead of renaming our defines, I chose to define only if not yet
defined, but to double check the value if already defined.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:02 -07:00
Lars Ellenberg
39e91a60c8 drbd: use resource name in workqueue
Since kernel 3.3, we can use snprintf-style arguments
to create a workqueue.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:02 -07:00
Lars Ellenberg
f5ec0173b9 drbd: debugfs: expose ed_data_gen_id
The effective data generation ID may be interesting for debugging
purposes of scenarios involving diskless states.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:02 -07:00
Lars Ellenberg
9fa4826919 drbd: prevent NULL pointer deref when resuming diskless primary
In a multiple error scenario, we may end up with a "frozen" Primary,
that has no access to any data (no local disk, no replication link).

If we then resume-io, we try to generate a new data generation id,
which will fail if there is no longer a local disk.

Double check for available local data,
which prevents the NULL pointer deref.

If we are diskless, turn the resume-io in this situation
into the first stage of a "force down", by bumping the "effective" data
gen id, which will prevent later attach or connect to the former data
set without first being demoted (deconfigured).

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:02 -07:00
Philipp Reisner
668700b40a drbd: Create a dedicated workqueue for sending acks on the control connection
The intention is to reduce CPU utilization. Recent measurements
unveiled that the current performance bottleneck is CPU utilization
on the receiving node. The asender thread became CPU limited.

One of the main points is to eliminate the idr_for_each_entry() loop
from the sending acks code path.

One exception in that is sending back ping_acks. These stay
in the ack-receiver thread. Otherwise the logic becomes too
complicated for no added value.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:01 -07:00
Philipp Reisner
1c03e52083 drbd: Rename asender to ack_receiver
This prepares the next patch where the sending on the meta (or
control) socket is moved to a dedicated workqueue.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:01 -07:00
Lars Ellenberg
6434f404b4 drbd: fix refcount error during detach of an already failed disk
A D_FAILED disk transitions as quickly as possible to
D_DISKLESS. But in the "unresponsive local disk" case,
there remains a time window where a administrative detach command could
find the disk already failed, but some internal meta data IO against the
unresponsive local disk still pending.

In that case, drbd_md_get_buffer() will return NULL.
Don't unconditionally call drbd_md_put_buffer(), or it will cause
refcount imbalance, and prevent any further re-attach on this volume
(until it is deleted and re-created).

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:01 -07:00
Lars Ellenberg
2b479766ee drbd: fix NULL deref in remember_new_state
The recent (not yet released) backport of the extended state broadcasts
to support the "events2" subcommand of drbdsetup had some glitches.

remember_old_state() would first count all connections with a
net_conf != NULL, then allocate a suitable array, then populate that
array with all connections found to have net_conf != NULL.

This races with the state change to C_STANDALONE,
and the NULL assignment there.

remember_new_state() then iterates over said connection array,
assuming that it would be fully populated.

But rcu_lock() just makes sure the thing some pointer points to,
if any, won't go away. It does not make the pointer itself immutable.

In fact there is no need to "filter" connections based on whether or not
they have a currently valid configuration.  Just record them always, if
they don't have a config, that's fine, there will be no change then.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:01 -07:00
Lars Ellenberg
84d34f2f07 drbd: improve network timeout detection
Don't blame the peer for being unresponsive,
if we did not even ask the question yet.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:01 -07:00
Lars Ellenberg
142207f782 drbd: drbd_panic_after_delayed_completion_of_aborted_request()
The only way to make DRBD intentionally call panic is to
set a disk timeout, have that trigger, "abort" some request and complete
to upper layers, then have the backend IO subsystem later complete these
requests successfully regardless.

As the attached IO pages have been recycled for other purposes
meanwhile, this will cause unexpected random memory changes.
To prevent corruption, we rather panic in that case.

Make it obvious from stack traces that this was the case by introducing
drbd_panic_after_delayed_completion_of_aborted_request().

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:01 -07:00
Lars Ellenberg
dc99562a48 drbd: add comment why we want to first call local-io-error, then send state
Even though we really want to get the state information about our bad
disk to the peer as soon as possible, it is useful to first call the
local-io-error handler.

People may chose to hard-reset the box from there.
If that looks and behaves exactly like a "regular node crash", without
bumping the data generation UUIDs on the peer in between, it makes it
easier to deal with.

If you intend to return from the local-io-error handler, then better
return as quickly as possible to avoid triggering other timeouts.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:01 -07:00
Lars Ellenberg
9bd2eb2c98 drbd: also bump UUIDs if a diskless primary connects
If for some reason the primary lost its disk *and* the replication link
before it is able to communicate the disk loss, probably blocked IO,
then later is able to re-establish the connection, the peer needs to
bump its UUIDs just like it does when peer only loses the disk
and is able to communicate this in time.

Otherwise, a later re-attach of the disk on the primary may start a
resync in the "wrong" direction.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-25 09:22:01 -07:00