First, number of CPUs can't be negative number.
Second, different signnnedness leads to suboptimal code in the following
cases:
1)
kmalloc(nr_cpu_ids * sizeof(X));
"int" has to be sign extended to size_t.
2)
while (loff_t *pos < nr_cpu_ids)
MOVSXD is 1 byte longed than the same MOV.
Other cases exist as well. Basically compiler is told that nr_cpu_ids
can't be negative which can't be deduced if it is "int".
Code savings on allyesconfig kernel: -3KB
add/remove: 0/0 grow/shrink: 25/264 up/down: 261/-3631 (-3370)
function old new delta
coretemp_cpu_online 450 512 +62
rcu_init_one 1234 1272 +38
pci_device_probe 374 399 +25
...
pgdat_reclaimable_pages 628 556 -72
select_fallback_rq 446 369 -77
task_numa_find_cpu 1923 1807 -116
Link: http://lkml.kernel.org/r/20170819114959.GA30580@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull block layer updates from Jens Axboe:
"This is the first pull request for 4.14, containing most of the code
changes. It's a quiet series this round, which I think we needed after
the churn of the last few series. This contains:
- Fix for a registration race in loop, from Anton Volkov.
- Overflow complaint fix from Arnd for DAC960.
- Series of drbd changes from the usual suspects.
- Conversion of the stec/skd driver to blk-mq. From Bart.
- A few BFQ improvements/fixes from Paolo.
- CFQ improvement from Ritesh, allowing idling for group idle.
- A few fixes found by Dan's smatch, courtesy of Dan.
- A warning fixup for a race between changing the IO scheduler and
device remova. From David Jeffery.
- A few nbd fixes from Josef.
- Support for cgroup info in blktrace, from Shaohua.
- Also from Shaohua, new features in the null_blk driver to allow it
to actually hold data, among other things.
- Various corner cases and error handling fixes from Weiping Zhang.
- Improvements to the IO stats tracking for blk-mq from me. Can
drastically improve performance for fast devices and/or big
machines.
- Series from Christoph removing bi_bdev as being needed for IO
submission, in preparation for nvme multipathing code.
- Series from Bart, including various cleanups and fixes for switch
fall through case complaints"
* 'for-4.14/block' of git://git.kernel.dk/linux-block: (162 commits)
kernfs: checking for IS_ERR() instead of NULL
drbd: remove BIOSET_NEED_RESCUER flag from drbd_{md_,}io_bio_set
drbd: Fix allyesconfig build, fix recent commit
drbd: switch from kmalloc() to kmalloc_array()
drbd: abort drbd_start_resync if there is no connection
drbd: move global variables to drbd namespace and make some static
drbd: rename "usermode_helper" to "drbd_usermode_helper"
drbd: fix race between handshake and admin disconnect/down
drbd: fix potential deadlock when trying to detach during handshake
drbd: A single dot should be put into a sequence.
drbd: fix rmmod cleanup, remove _all_ debugfs entries
drbd: Use setup_timer() instead of init_timer() to simplify the code.
drbd: fix potential get_ldev/put_ldev refcount imbalance during attach
drbd: new disk-option disable-write-same
drbd: Fix resource role for newly created resources in events2
drbd: mark symbols static where possible
drbd: Send P_NEG_ACK upon write error in protocol != C
drbd: add explicit plugging when submitting batches
drbd: change list_for_each_safe to while(list_first_entry_or_null)
drbd: introduce drbd_recv_header_maybe_unplug
...
xive_spapr_init() is called from a __init routine and calls __init
routines.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Having the CPU identifier in the debug logs is helpful when tracking
issues. Also add some more logging and fix a compile issue in
xive_do_source_eoi().
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The H_INT_ESB hcall() is used to issue a load or store to the ESB page
instead of using the MMIO pages. This can be used as a workaround on
some HW issues. The OS knows that this hcall should be used on an
interrupt source when the ESB hcall flag is set to 1 in the hcall
H_INT_GET_SOURCE_INFO.
To maintain the frontier between the xive frontend and backend, we
introduce a new xive operation 'esb_rw' to be used in the routines
doing memory accesses on the ESBs.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
It will be required later by the H_INT_ESB hcall.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Some source support MMIO stores on the ESB page to perform EOI. Let's
introduce a specific routine for this case even if this should be the
only use of it.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
xive_poke_esb() is performing a load/read so it is better named as
xive_esb_read() as we will need to introduce a xive_esb_write()
routine. Also use the XIVE_ESB_LOAD_EOI offset when EOI'ing LSI
interrupts.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This is the framework for using XIVE in a PowerVM guest. The support
is very similar to the native one in a much simpler form.
Each source is associated with an Event State Buffer (ESB). This is a
two bit state machine which is used to trigger events. The bits are
named "P" (pending) and "Q" (queued) and can be controlled by MMIO.
The Guest OS registers event (or notifications) queues on which the HW
will post event data for a target to notify.
Instead of OPAL calls, a set of Hypervisors call are used to configure
the interrupt sources and the event/notification queues of the guest:
- H_INT_GET_SOURCE_INFO
used to obtain the address of the MMIO page of the Event State
Buffer (PQ bits) entry associated with the source.
- H_INT_SET_SOURCE_CONFIG
assigns a source to a "target".
- H_INT_GET_SOURCE_CONFIG
determines to which "target" and "priority" is assigned to a source
- H_INT_GET_QUEUE_INFO
returns the address of the notification management page associated
with the specified "target" and "priority".
- H_INT_SET_QUEUE_CONFIG
sets or resets the event queue for a given "target" and "priority".
It is also used to set the notification config associated with the
queue, only unconditional notification for the moment. Reset is
performed with a queue size of 0 and queueing is disabled in that
case.
- H_INT_GET_QUEUE_CONFIG
returns the queue settings for a given "target" and "priority".
- H_INT_RESET
resets all of the partition's interrupt exploitation structures to
their initial state, losing all configuration set via the hcalls
H_INT_SET_SOURCE_CONFIG and H_INT_SET_QUEUE_CONFIG.
- H_INT_SYNC
issue a synchronisation on a source to make sure sure all
notifications have reached their queue.
As for XICS, the XIVE interface for the guest is described in the
device tree under the "interrupt-controller" node. A couple of new
properties are specific to XIVE :
- "reg"
contains the base address and size of the thread interrupt
managnement areas (TIMA), also called rings, for the User level and
for the Guest OS level. Only the Guest OS level is taken into
account today.
- "ibm,xive-eq-sizes"
the size of the event queues. One cell per size supported, contains
log2 of size, in ascending order.
- "ibm,xive-lisn-ranges"
the interrupt numbers ranges assigned to the guest. These are
allocated using a simple bitmap.
and also :
- "/ibm,plat-res-int-priorities"
contains a list of priorities that the hypervisor has reserved for
its own use.
Tested with a QEMU XIVE model for pseries and with the Power hypervisor.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This routine will be used in the spapr backend. Also introduce a short
xive_alloc_order() helper.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* Return directly after a call of the function "kzalloc" failed
at the beginning.
* Delete a repeated check for the local variable "bank"
which became unnecessary with this refactoring.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Replace the specification of a data structure by a pointer dereference
as the parameter for the operator "sizeof" to make the corresponding size
determination a bit safer according to the Linux coding style convention.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When called from xive_irq_startup(), the size of the cpumask can be
larger than nr_cpu_ids. This can result in a WARN_ON such as:
WARNING: CPU: 10 PID: 1 at ../arch/powerpc/sysdev/xive/common.c:476 xive_find_target_in_mask+0x110/0x2f0
...
NIP [c00000000008a310] xive_find_target_in_mask+0x110/0x2f0
LR [c00000000008a2e4] xive_find_target_in_mask+0xe4/0x2f0
Call Trace:
xive_find_target_in_mask+0x74/0x2f0 (unreliable)
xive_pick_irq_target.isra.1+0x200/0x230
xive_irq_startup+0x60/0x180
irq_startup+0x70/0xd0
__setup_irq+0x7bc/0x880
request_threaded_irq+0x14c/0x2c0
request_event_sources_irqs+0x100/0x180
__machine_initcall_pseries_init_ras_IRQ+0x104/0x134
do_one_initcall+0x68/0x1d0
kernel_init_freeable+0x290/0x374
kernel_init+0x24/0x170
ret_from_kernel_thread+0x5c/0x74
This happens because we're being called with our affinity mask set to
irq_default_affinity. That in turn was populated using
cpumask_setall(), which sets NR_CPUs worth of bits, not nr_cpu_ids
worth. Finally cpumask_weight() will return > nr_cpu_ids when passed a
mask which has > nr_cpu_ids bits set.
Fix it by limiting the value returned by cpumask_weight().
Signed-off-by: Cédric Le Goater <clg@kaod.org>
[mpe: Add change log details on actual cause]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This way we don't need a block_device structure to submit I/O. The
block_device has different life time rules from the gendisk and
request_queue and is usually only available when the block device node
is open. Other callers need to explicitly create one (e.g. the lightnvm
passthrough code, or the new nvme multipathing code).
For the actual I/O path all that we need is the gendisk, which exists
once per block device. But given that the block layer also does
partition remapping we additionally need a partition index, which is
used for said remapping in generic_make_request.
Note that all the block drivers generally want request_queue or
sometimes the gendisk, so this removes a layer of indirection all
over the stack.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that we have a custom printf format specifier, convert users of
full_name to use %pOF instead. This is preparation to remove storing
of the full path string for each node.
Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: Scott Wood <oss@buserror.net>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linuxppc-dev@lists.ozlabs.org
Reviewed-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Declare bin_attribute structures as const as they are only passed as an
argument to the function sysfs_create_bin_file. This argument is of
type const, so declare the structure as const.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Exclude core xmon files from ftrace (along with an xmon xive helper
outside of xmon/) to minimize impact of ftrace while within xmon.
Before:
/sys/kernel/debug/tracing# grep -ci xmon available_filter_functions
26
After:
/sys/kernel/debug/tracing# grep -ci xmon available_filter_functions
0
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
[mpe: Use $(subst ..) on KBUILD_CFLAGS rather than CFLAGS_REMOVE_xxx]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Both xive_core_init() and xive_native_init() are called from and call
__init routines, so they should also be __init.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
mpc8xx_pic.c is dedicated to the 8xx, so move it to platform/8xx
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
To remain consistent with what is done with CPM2, let's link
CPM1 related parts to CONFIG_CPM1 instead of CONFIG_8xx
When something depends on both CPM1 and CPM2 we associate it
with CONFIG_CPM
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We have a lot of code in sysdev for supporting 4xx, ie. either 40x or
44x. Instead it would be cleaner if it was all in platforms/4xx.
This is slightly odd in that we don't actually define any machines in
the 4xx platform, as is usual for a platform directory. But still it
seems like a better result to have all this related code in a directory
by itself.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ensure irqd is active before attempting to set affinity. This should
make the set affinity code more robust. For instance, this prevents
these messages seen on a 4.12 based kernel when taking cpus offline:
[ 123.053037264,3] XIVE[ IC 00 ] ISN 2 lead to invalid IVE !
[ 77.885859] xive: Error -6 reconfiguring irq 17
[ 77.885862] IRQ17: set affinity failed(-6).
That particular case has been fixed in 4.13-rc1 by commit
91f26cb4cd ("genirq/cpuhotplug: Do not migrated shutdown irqs").
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
External IRQ0 (index 48) has the same capabilities as the other IRQ1-7
and is handled by the same register IPIC_SEPNR. When this register is
not specified for "ack" in "ipic_info", you cannot configure this IRQ
as IRQ_TYPE_EDGE_FALLING. This oversight was probably due to the
non-contiguous hwirq numbering of IRQ0 in the IPIC.
Signed-off-by: Jurgen Schindele <schindele@nentec.de>
[scottwood: Cleaned up commit message and posted as a proper patch]
Signed-off-by: Scott Wood <oss@buserror.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Highlights include:
- Support for STRICT_KERNEL_RWX on 64-bit server CPUs.
- Platform support for FSP2 (476fpe) board
- Enable ZONE_DEVICE on 64-bit server CPUs.
- Generic & powerpc spin loop primitives to optimise busy waiting
- Convert VDSO update function to use new update_vsyscall() interface
- Optimisations to hypercall/syscall/context-switch paths
- Improvements to the CPU idle code on Power8 and Power9.
As well as many other fixes and improvements.
Thanks to:
Akshay Adiga, Andrew Donnellan, Andrew Jeffery, Anshuman Khandual, Anton
Blanchard, Balbir Singh, Benjamin Herrenschmidt, Christophe Leroy, Christophe
Lombard, Colin Ian King, Dan Carpenter, Gautham R. Shenoy, Hari Bathini, Ian
Munsie, Ivan Mikhaylov, Javier Martinez Canillas, Madhavan Srinivasan,
Masahiro Yamada, Matt Brown, Michael Neuling, Michal Suchanek, Murilo
Opsfelder Araujo, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Paul
Mackerras, Pavel Machek, Russell Currey, Santosh Sivaraj, Stephen Rothwell,
Thiago Jung Bauermann, Yang Li.
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Merge tag 'powerpc-4.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Highlights include:
- Support for STRICT_KERNEL_RWX on 64-bit server CPUs.
- Platform support for FSP2 (476fpe) board
- Enable ZONE_DEVICE on 64-bit server CPUs.
- Generic & powerpc spin loop primitives to optimise busy waiting
- Convert VDSO update function to use new update_vsyscall() interface
- Optimisations to hypercall/syscall/context-switch paths
- Improvements to the CPU idle code on Power8 and Power9.
As well as many other fixes and improvements.
Thanks to: Akshay Adiga, Andrew Donnellan, Andrew Jeffery, Anshuman
Khandual, Anton Blanchard, Balbir Singh, Benjamin Herrenschmidt,
Christophe Leroy, Christophe Lombard, Colin Ian King, Dan Carpenter,
Gautham R. Shenoy, Hari Bathini, Ian Munsie, Ivan Mikhaylov, Javier
Martinez Canillas, Madhavan Srinivasan, Masahiro Yamada, Matt Brown,
Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Naveen N.
Rao, Nicholas Piggin, Oliver O'Halloran, Paul Mackerras, Pavel Machek,
Russell Currey, Santosh Sivaraj, Stephen Rothwell, Thiago Jung
Bauermann, Yang Li"
* tag 'powerpc-4.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (158 commits)
powerpc/Kconfig: Enable STRICT_KERNEL_RWX for some configs
powerpc/mm/radix: Implement STRICT_RWX/mark_rodata_ro() for Radix
powerpc/mm/hash: Implement mark_rodata_ro() for hash
powerpc/vmlinux.lds: Align __init_begin to 16M
powerpc/lib/code-patching: Use alternate map for patch_instruction()
powerpc/xmon: Add patch_instruction() support for xmon
powerpc/kprobes/optprobes: Use patch_instruction()
powerpc/kprobes: Move kprobes over to patch_instruction()
powerpc/mm/radix: Fix execute permissions for interrupt_vectors
powerpc/pseries: Fix passing of pp0 in updatepp() and updateboltedpp()
powerpc/64s: Blacklist rtas entry/exit from kprobes
powerpc/64s: Blacklist functions invoked on a trap
powerpc/64s: Un-blacklist system_call() from kprobes
powerpc/64s: Move system_call() symbol to just after setting MSR_EE
powerpc/64s: Blacklist system_call() and system_call_common() from kprobes
powerpc/64s: Convert .L__replay_interrupt_return to a local label
powerpc64/elfv1: Only dereference function descriptor for non-text symbols
cxl: Export library to support IBM XSL
powerpc/dts: Use #include "..." to include local DT
powerpc/perf/hv-24x7: Aggregate result elements on POWER9 SMT8
...
* Introduce the _flushcache() family of memory copy helpers and use them
for persistent memory write operations on x86. The _flushcache()
semantic indicates that the cache is either bypassed for the copy
operation (movnt) or any lines dirtied by the copy operation are
written back (clwb, clflushopt, or clflush).
* Extend dax_operations with ->copy_from_iter() and ->flush()
operations. These operations and other infrastructure updates allow
all persistent memory specific dax functionality to be pushed into
libnvdimm and the pmem driver directly. It also allows dax-specific
sysfs attributes to be linked to a host device, for example:
/sys/block/pmem0/dax/write_cache
* Add support for the new NVDIMM platform/firmware mechanisms introduced
in ACPI 6.2 and UEFI 2.7. This support includes the v1.2 namespace
label format, extensions to the address-range-scrub command set, new
error injection commands, and a new BTT (block-translation-table)
layout. These updates support inter-OS and pre-OS compatibility.
* Fix a longstanding memory corruption bug in nfit_test.
* Make the pmem and nvdimm-region 'badblocks' sysfs files poll(2)
capable.
* Miscellaneous fixes and small updates across libnvdimm and the nfit
driver.
Acknowledgements that came after the branch was pushed:
commit 6aa734a2f3 "libnvdimm, region, pmem: fix 'badblocks'
sysfs_get_dirent() reference lifetime"
Reviewed-by: Toshi Kani <toshi.kani@hpe.com>
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Merge tag 'libnvdimm-for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"libnvdimm updates for the latest ACPI and UEFI specifications. This
pull request also includes new 'struct dax_operations' enabling to
undo the abuse of copy_user_nocache() for copy operations to pmem.
The dax work originally missed 4.12 to address concerns raised by Al.
Summary:
- Introduce the _flushcache() family of memory copy helpers and use
them for persistent memory write operations on x86. The
_flushcache() semantic indicates that the cache is either bypassed
for the copy operation (movnt) or any lines dirtied by the copy
operation are written back (clwb, clflushopt, or clflush).
- Extend dax_operations with ->copy_from_iter() and ->flush()
operations. These operations and other infrastructure updates allow
all persistent memory specific dax functionality to be pushed into
libnvdimm and the pmem driver directly. It also allows dax-specific
sysfs attributes to be linked to a host device, for example:
/sys/block/pmem0/dax/write_cache
- Add support for the new NVDIMM platform/firmware mechanisms
introduced in ACPI 6.2 and UEFI 2.7. This support includes the v1.2
namespace label format, extensions to the address-range-scrub
command set, new error injection commands, and a new BTT
(block-translation-table) layout. These updates support inter-OS
and pre-OS compatibility.
- Fix a longstanding memory corruption bug in nfit_test.
- Make the pmem and nvdimm-region 'badblocks' sysfs files poll(2)
capable.
- Miscellaneous fixes and small updates across libnvdimm and the nfit
driver.
Acknowledgements that came after the branch was pushed: commit
6aa734a2f3 ("libnvdimm, region, pmem: fix 'badblocks'
sysfs_get_dirent() reference lifetime") was reviewed by Toshi Kani
<toshi.kani@hpe.com>"
* tag 'libnvdimm-for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (42 commits)
libnvdimm, namespace: record 'lbasize' for pmem namespaces
acpi/nfit: Issue Start ARS to retrieve existing records
libnvdimm: New ACPI 6.2 DSM functions
acpi, nfit: Show bus_dsm_mask in sysfs
libnvdimm, acpi, nfit: Add bus level dsm mask for pass thru.
acpi, nfit: Enable DSM pass thru for root functions.
libnvdimm: passthru functions clear to send
libnvdimm, btt: convert some info messages to warn/err
libnvdimm, region, pmem: fix 'badblocks' sysfs_get_dirent() reference lifetime
libnvdimm: fix the clear-error check in nsio_rw_bytes
libnvdimm, btt: fix btt_rw_page not returning errors
acpi, nfit: quiet invalid block-aperture-region warnings
libnvdimm, btt: BTT updates for UEFI 2.7 format
acpi, nfit: constify *_attribute_group
libnvdimm, pmem: disable dax flushing when pmem is fronting a volatile region
libnvdimm, pmem, dax: export a cache control attribute
dax: convert to bitmask for flags
dax: remove default copy_from_iter fallback
libnvdimm, nfit: enable support for volatile ranges
libnvdimm, pmem: fix persistence warning
...
Merge our fixes branch, a few of them are tripping people up while
working on top of next, and we also have a dependency between the CXL
fixes and new CXL code we want to merge into next.
There is no reason for that message to be pr_info(), it will be printed
every time we start a KVM guest.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Require all dax-drivers to register a ->copy_from_iter() operation so
that it is clear which dax_operations are optional and which must be
implemented for filesystem-dax to operate.
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Architecturally we should apply a 0x400 offset for these. Not doing
it will break future HW implementations.
The offset of 0 is supposed to remain for "triggers" though not all
sources support both trigger and store EOI, and in P9 specifically,
some sources will treat 0 as a store EOI. But future chips will not.
So this makes us use the properly architected offset which should work
always.
Fixes: 243e25112d ("powerpc/xive: Native exploitation of the XIVE interrupt controller")
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Collation of some spelling fixes from Colin.
Attemping -> Attempting
intialized -> initialized
missmanaged -> mismanaged
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
IRQ 0 is a valid HW interrupt. So get_irq() shall return 0 when
there is no irq, instead of returning irq_linear_revmap(... ,0)
Fixes: f2a0bd3753 ("[POWERPC] 8xx: powerpc port of core CPM PIC")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Highlights include:
- rework the Linux page table geometry to lower memory usage on 64-bit Book3S
(IBM chips) using the Hash MMU.
- support for a new device tree binding for discovering CPU features on future
firmwares.
- Freescale updates from Scott: "Includes a fix for a powerpc/next mm regression
on 64e, a fix for a kernel hang on 64e when using a debugger inside a
relocated kernel, a qman fix, and misc qe improvements."
Thanks to:
Christophe Leroy, Gavin Shan, Horia Geantă, LiuHailong, Nicholas Piggin, Roy
Pledge, Scott Wood, Valentin Longchamp.
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Merge tag 'powerpc-4.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull more powerpc updates from Michael Ellerman:
"The change to the Linux page table geometry was delayed for more
testing with 16G pages, and there's the new CPU features stuff which
just needed one more polish before going in. Plus a few changes from
Scott which came in a bit late. And then various fixes, mostly minor.
Summary highlights:
- rework the Linux page table geometry to lower memory usage on
64-bit Book3S (IBM chips) using the Hash MMU.
- support for a new device tree binding for discovering CPU features
on future firmwares.
- Freescale updates from Scott:
"Includes a fix for a powerpc/next mm regression on 64e, a fix for
a kernel hang on 64e when using a debugger inside a relocated
kernel, a qman fix, and misc qe improvements."
Thanks to: Christophe Leroy, Gavin Shan, Horia Geantă, LiuHailong,
Nicholas Piggin, Roy Pledge, Scott Wood, Valentin Longchamp"
* tag 'powerpc-4.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/64s: Support new device tree binding for discovering CPU features
powerpc: Don't print cpu_spec->cpu_name if it's NULL
of/fdt: introduce of_scan_flat_dt_subnodes and of_get_flat_dt_phandle
powerpc/64s: Fix unnecessary machine check handler relocation branch
powerpc/mm/book3s/64: Rework page table geometry for lower memory usage
powerpc: Fix distclean with Makefile.postlink
powerpc/64e: Don't place the stack beyond TASK_SIZE
powerpc/powernv: Block PCI config access on BCM5718 during EEH recovery
powerpc/8xx: Adding support of IRQ in MPC8xx GPIO
soc/fsl/qbman: Disable IRQs for deferred QBMan work
soc/fsl/qe: add EXPORT_SYMBOL for the 2 qe_tdm functions
soc/fsl/qe: only apply QE_General4 workaround on affected SoCs
soc/fsl/qe: round brg_freq to 1kHz granularity
soc/fsl/qe: get rid of immrbar_virt_to_phys()
net: ethernet: ucc_geth: fix MEM_PART_MURAM mode
powerpc/64e: Fix hang when debugging programs with relocated kernel
The main thing here is a new implementation of the in-kernel
XICS interrupt controller emulation for POWER9 machines, from Ben
Herrenschmidt.
POWER9 has a new interrupt controller called XIVE (eXternal Interrupt
Virtualization Engine) which is able to deliver interrupts directly
to guest virtual CPUs in hardware without hypervisor intervention.
With this new code, the guest still sees the old XICS interface but
performance is better because the XICS emulation in the host uses the
XIVE directly rather than going through a XICS emulation in firmware.
Conflicts:
arch/powerpc/kernel/cpu_setup_power.S [cherry-picked fix]
arch/powerpc/kvm/book3s_xive.c [include asm/debugfs.h]
* Region media error reporting: A libnvdimm region device is the parent
to one or more namespaces. To date, media errors have been reported via
the "badblocks" attribute attached to pmem block devices for namespaces
in "raw" or "memory" mode. Given that namespaces can be in "device-dax"
or "btt-sector" mode this new interface reports media errors
generically, i.e. independent of namespace modes or state. This
subsequently allows userspace tooling to craft "ACPI 6.1 Section
9.20.7.6 Function Index 4 - Clear Uncorrectable Error" requests and
submit them via the ioctl path for NVDIMM root bus devices.
* Introduce 'struct dax_device' and 'struct dax_operations': Prompted by
a request from Linus and feedback from Christoph this allows for dax
capable drivers to publish their own custom dax operations. This fixes
the broken assumption that all dax operations are related to a
persistent memory device, and makes it easier for other architectures
and platforms to add customized persistent memory support.
* 'libnvdimm' core updates: A new "deep_flush" sysfs attribute is
available for storage appliance applications to manually trigger memory
controllers to drain write-pending buffers that would otherwise be
flushed automatically by the platform ADR (asynchronous-DRAM-refresh)
mechanism at a power loss event. Support for "locked" DIMMs is included
to prevent namespaces from surfacing when the namespace label data area
is locked. Finally, fixes for various reported deadlocks and crashes,
also tagged for -stable.
* ACPI / nfit driver updates: General updates of the nfit driver to add
DSM command overrides, ACPI 6.1 health state flags support, DSM payload
debug available by default, and various fixes.
Acknowledgements that came after the branch was pushed:
commmit 565851c972 "device-dax: fix sysfs attribute deadlock"
Tested-by: Yi Zhang <yizhan@redhat.com>
commit 23f4984483 "libnvdimm: rework region badblocks clearing"
Tested-by: Toshi Kani <toshi.kani@hpe.com>
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Merge tag 'libnvdimm-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"The bulk of this has been in multiple -next releases. There were a few
late breaking fixes and small features that got added in the last
couple days, but the whole set has received a build success
notification from the kbuild robot.
Change summary:
- Region media error reporting: A libnvdimm region device is the
parent to one or more namespaces. To date, media errors have been
reported via the "badblocks" attribute attached to pmem block
devices for namespaces in "raw" or "memory" mode. Given that
namespaces can be in "device-dax" or "btt-sector" mode this new
interface reports media errors generically, i.e. independent of
namespace modes or state.
This subsequently allows userspace tooling to craft "ACPI 6.1
Section 9.20.7.6 Function Index 4 - Clear Uncorrectable Error"
requests and submit them via the ioctl path for NVDIMM root bus
devices.
- Introduce 'struct dax_device' and 'struct dax_operations': Prompted
by a request from Linus and feedback from Christoph this allows for
dax capable drivers to publish their own custom dax operations.
This fixes the broken assumption that all dax operations are
related to a persistent memory device, and makes it easier for
other architectures and platforms to add customized persistent
memory support.
- 'libnvdimm' core updates: A new "deep_flush" sysfs attribute is
available for storage appliance applications to manually trigger
memory controllers to drain write-pending buffers that would
otherwise be flushed automatically by the platform ADR
(asynchronous-DRAM-refresh) mechanism at a power loss event.
Support for "locked" DIMMs is included to prevent namespaces from
surfacing when the namespace label data area is locked. Finally,
fixes for various reported deadlocks and crashes, also tagged for
-stable.
- ACPI / nfit driver updates: General updates of the nfit driver to
add DSM command overrides, ACPI 6.1 health state flags support, DSM
payload debug available by default, and various fixes.
Acknowledgements that came after the branch was pushed:
- commmit 565851c972 "device-dax: fix sysfs attribute deadlock":
Tested-by: Yi Zhang <yizhan@redhat.com>
- commit 23f4984483 "libnvdimm: rework region badblocks clearing"
Tested-by: Toshi Kani <toshi.kani@hpe.com>"
* tag 'libnvdimm-for-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (52 commits)
libnvdimm, pfn: fix 'npfns' vs section alignment
libnvdimm: handle locked label storage areas
libnvdimm: convert NDD_ flags to use bitops, introduce NDD_LOCKED
brd: fix uninitialized use of brd->dax_dev
block, dax: use correct format string in bdev_dax_supported
device-dax: fix sysfs attribute deadlock
libnvdimm: restore "libnvdimm: band aid btt vs clear poison locking"
libnvdimm: fix nvdimm_bus_lock() vs device_lock() ordering
libnvdimm: rework region badblocks clearing
acpi, nfit: kill ACPI_NFIT_DEBUG
libnvdimm: fix clear length of nvdimm_forget_poison()
libnvdimm, pmem: fix a NULL pointer BUG in nd_pmem_notify
libnvdimm, region: sysfs trigger for nvdimm_flush()
libnvdimm: fix phys_addr for nvdimm_clear_poison
x86, dax, pmem: remove indirection around memcpy_from_pmem()
block: remove block_device_operations ->direct_access()
block, dax: convert bdev_dax_supported() to dax_direct_access()
filesystem-dax: convert to dax_direct_access()
Revert "block: use DAX for partition table reads"
ext2, ext4, xfs: retrieve dax_device for iomap operations
...
This patch allows the use of IRQ to notify the change of GPIO status
on MPC8xx CPM IO ports. This then allows to associate IRQs to GPIOs
in the Device Tree.
Ex:
CPM1_PIO_C: gpio-controller@960 {
#gpio-cells = <2>;
compatible = "fsl,cpm1-pario-bank-c";
reg = <0x960 0x10>;
fsl,cpm1-gpio-irq-mask = <0x0fff>;
interrupts = <1 2 6 9 10 11 14 15 23 24 26 31>;
interrupt-parent = <&CPM_PIC>;
gpio-controller;
};
The property 'fsl,cpm1-gpio-irq-mask' defines which of the 16 GPIOs
have the associated interrupts defined in the 'interrupts' property.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
This patch makes KVM capable of using the XIVE interrupt controller
to provide the standard PAPR "XICS" style hypercalls. It is necessary
for proper operations when the host uses XIVE natively.
This has been lightly tested on an actual system, including PCI
pass-through with a TG3 device.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Cleanup pr_xxx(), unsplit pr_xxx() strings, etc., fix build
failures by adding KVM_XIVE which depends on KVM_XICS and XIVE, and
adding empty stubs for the kvm_xive_xxx() routines, fixup subject,
integrate fixes from Paul for building PR=y HV=n]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Recently we merged the native xive support for Power9, and then separately some
reworks for doorbell IPI support. In isolation both series were OK, but the
merged result had a bug in one case.
On P9 DD1 we use pnv_p9_dd1_cause_ipi() which tries to use doorbells, and then
falls back to the interrupt controller. However the fallback is implemented by
calling icp_ops->cause_ipi. But now that xive support is merged we might be
using xive, in which case icp_ops is not initialised, it's a xics specific
structure. This leads to an oops such as:
Unable to handle kernel paging request for data at address 0x00000028
Oops: Kernel access of bad area, sig: 11 [#1]
NIP pnv_p9_dd1_cause_ipi+0x74/0xe0
LR smp_muxed_ipi_message_pass+0x54/0x70
To fix it, rather than using icp_ops which might be NULL, have both xics and
xive set smp_ops->cause_ipi, and then in the powernv code we save that as
ic_cause_ipi before overriding smp_ops->cause_ipi. For paranoia add a WARN_ON()
to check if somehow smp_ops->cause_ipi is NULL.
Fixes: b866cc2199 ("powerpc: Change the doorbell IPI calling convention")
Tested-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Now that all the producers and consumers of dax interfaces have been
converted to using dax_operations on a dax_device, remove the block
device direct_access enabling.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Dan Carpenter noticed that the code in __xive_native_disable_queue() has a for
loop with an unconditional break in the middle, which doesn't make a lot of
sense.
What the code's supposed to do is loop as long as OPAL says it's busy, if we get
any other return code, either success or failure, then we should break the loop.
So add the missing check.
Fixes: 243e25112d ("powerpc/xive: Native exploitation of the XIVE interrupt controller")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Setup a dax_device to have the same lifetime as the axon_ram block
device and add a ->direct_access() method that is equivalent to
axon_ram_direct_access(). Once fs/dax.c has been converted to use
dax_operations the old axon_ram_direct_access() will be removed.
Reported-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Change the doorbell callers to know about their msgsnd addressing,
rather than have them set a per-cpu target data tag at boot that gets
sent to the cause_ipi functions. The data is only used for doorbell IPI
functions, no other IPI types, so it makes sense to keep that detail
local to doorbell.
Have the platform code understand doorbell IPIs, rather than the
interrupt controller code understand them. Platform code can look at
capabilities it has available and decide which to use.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This merges the arch part of the XIVE support, leaving the final commit
with the KVM specific pieces dangling on the branch for Paul to merge
via the kvm-ppc tree.
powerpc_debugfs_root is the dentry representing the root of the
"powerpc" directory tree in debugfs.
Currently it sits in asm/debug.h, a long with some other things that
have "debug" in the name, but are otherwise unrelated.
Pull it out into a separate header, which also includes linux/debugfs.h,
and convert all the users to include debugfs.h instead of debug.h.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
We have all sort of variants of MMIO accessors for the real mode
instructions. This creates a clean set of accessors based on
Linux normal naming conventions, replacing all occurrences of
the old ones in the tree.
I have purposefully removed the "out/in" variants in favor of
only including __raw variants. Any code using these is already
pretty much hand tuned to operate in a very specific environment.
I've fixed up the 2 users (only one of them actually needed
a barrier in the first place).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The XIVE interrupt controller is the new interrupt controller
found in POWER9. It supports advanced virtualization capabilities
among other things.
Currently we use a set of firmware calls that simulate the old
"XICS" interrupt controller but this is fairly inefficient.
This adds the framework for using XIVE along with a native
backend which OPAL for configuration. Later, a backend allowing
the use in a KVM or PowerVM guest will also be provided.
This disables some fast path for interrupts in KVM when XIVE is
enabled as these rely on the firmware emulation code which is no
longer available when the XIVE is used natively by Linux.
A latter patch will make KVM also directly exploit the XIVE, thus
recovering the lost performance (and more).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[mpe: Fixup pr_xxx("XIVE:"...), don't split pr_xxx() strings,
tweak Kconfig so XIVE_NATIVE selects XIVE and depends on POWERNV,
fix build errors when SMP=n, fold in fixes from Ben:
Don't call cpu_online() on an invalid CPU number
Fix irq target selection returning out of bounds cpu#
Extra sanity checks on cpu numbers
]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
It is invalid to call del_gendisk() when disk->queue is NULL. Fix error
handling in axon_ram_probe() to avoid doing that.
Also del_gendisk() does not drop a reference to gendisk allocated by
alloc_disk(). That has to be done by put_disk(). Add that call where
needed.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
The CPPR (Current Processor Priority Register) of a XICS interrupt
presentation controller contains a value N, such that only interrupts
with a priority "more favoured" than N will be received by the CPU,
where "more favoured" means "less than". So if the CPPR has the value 5
then only interrupts with a priority of 0-4 inclusive will be received.
In theory the CPPR can support a value of 0 to 255 inclusive.
In practice Linux only uses values of 0, 4, 5 and 0xff. Setting the CPPR
to 0 rejects all interrupts, setting it to 0xff allows all interrupts.
The values 4 and 5 are used to differentiate IPIs from external
interrupts. Setting the CPPR to 5 allows IPIs to be received but not
external interrupts.
The CPPR emulation in the OPAL XICS implementation only directly
supports priorities 0 and 0xff. All other priorities are considered
equivalent, and mapped to a single priority value internally. This means
when using icp-opal we can not allow IPIs but not externals.
This breaks Linux's use of priority values when a CPU is hot unplugged.
After migrating IRQs away from the CPU that is being offlined, we set
the priority to 5, meaning we still want the offline CPU to receive
IPIs. But the effect of the OPAL XICS emulation's use of a single
priority value is that all interrupts are rejected by the CPU. With the
CPU offline, and not receiving IPIs, we may not be able to wake it up to
bring it back online.
The first part of the fix is in icp_opal_set_cpu_priority(). CPPR values
of 0 to 4 inclusive will correctly cause all interrupts to be rejected,
so we pass those CPPR values through to OPAL. However if we are called
with a CPPR of 5 or greater, the caller is expecting to be able to allow
IPIs but not external interrupts. We know this doesn't work, so instead
of rejecting all interrupts we choose the opposite which is to allow all
interrupts. This is still not correct behaviour, but we know for the
only existing caller (xics_migrate_irqs_away()), that it is the better
option.
The other part of the fix is in xics_migrate_irqs_away(). Instead of
setting priority (CPPR) to 0, and then back to 5 before migrating IRQs,
we migrate the IRQs before setting the priority back to 5. This should
have no effect on an ICP backend with a working set_priority(), and on
icp-opal it means we will keep all interrupts blocked until after we've
finished doing the IRQ migration. Additionally we wait for 5ms after
doing the migration to make sure there are no IRQs in flight.
Fixes: d74361881f ("powerpc/xics: Add ICP OPAL backend")
Cc: stable@vger.kernel.org # v4.8+
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Reported-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Tested-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Balbir Singh <bsingharora@gmail.com>
[mpe: Rewrote comments and change log, change delay to 5ms]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Otherwise KVM will fail to pass them through to the host
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Alexey Dobriyan