Now that irq sum accounting for /proc/stat's "intr" line works again we
have the oddity that the sum field (first field) contains only the sum
of the second (external irqs) and third field (I/O interrupts).
The reason for that is that these two fields are already sums of all other
fields. So if we would sum up everything we would count every interrupt
twice.
This is broken since the split interrupt accounting was merged two years
ago: 052ff461 "[S390] irq: have detailed
statistics for interrupt types".
To fix this remove the split interrupt fields from /proc/stat's "intr"
line again and only have them in /proc/interrupts.

This restores the old behaviour, seems to be the only sane fix and mimics
a behaviour from other architectures where /proc/interrupts also contains
more than /proc/stat's "intr" line does.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

virtio network device multiqueue support reserves
vq 3 for future use (useful both for future extensions and to make it
pretty - this way receive vqs have even and transmit - odd numbers).
Make it possible to skip initialization for
specific vq numbers by specifying NULL for name.
Document this usage as well as (existing) NULL callback.

Drivers using this not coded up yet, so I simply tested
with virtio-pci and verified that this patch does
not break existing drivers.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Instead of storing the queue index in transport-specific virtio structs,
this patch moves them to vring_virtqueue and introduces an helper to get
the value.  This lets drivers simplify their management and tracing of
virtqueues.
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.

Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>

For processing under KVM it is required to detect
the actual SCLP console type in order to set it as
preferred console.
Signed-off-by: NHeinz Graalfs <graalfs@linux.vnet.ibm.com>
Acked-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: NPeter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

The external interrupt handlers have a parameter called ext_int_code.
Besides the name this paramter does not only contain the ext_int_code
but in addition also the "cpu address" (POP) which caused the external
interrupt.
To make the code a bit more obvious pass a struct instead so the called
function can easily distinguish between external interrupt code and
cpu address. The cpu address field however is named "subcode" since
some external interrupt sources do not pass a cpu address but a
different parameter (or none at all).
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

We were cheating with our barriers; using the smp ones rather than the
real device ones.  That was fine, until rpmsg came along, which is
used to talk to a real device (a non-SMP CPU).

Unfortunately, just putting back the real barriers (reverting
d57ed95d) causes a performance regression on virtio-pci.  In
particular, Amos reports netbench's TCP_RR over virtio_net CPU
utilization increased up to 35% while throughput went down by up to
14%.

By comparison, this branch is in the noise.

Reference: https://lkml.org/lkml/2011/12/11/22Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Add a new .bus_name to virtio_config_ops then modify virtio_net to
call through to it in an ethtool .get_drvinfo routine to report
bus_info in ethtool -i output which is consistent with other
emulated NICs and the output of lspci.
Signed-off-by: NRick Jones <rick.jones2@hp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix several compile errors on s390 caused by splitting module.h.

Some include additions [e.g. qdio_setup.c, zfcp_qdio.c] are in
anticipation of pending changes queued for s390 that increase
the modular use footprint.

[PG: added additional obvious changes since Heiko's original patch]
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

to_kvmdev and dev_to_virtio both use container_of. Avoid to nest the
two macros to quiet the following sparse warning:

drivers/s390/kvm/kvm_virtio.c:337:20: warning: symbol '__mptr' shadows an earlier one
drivers/s390/kvm/kvm_virtio.c:337:20: originally declared here
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Make functions and data static to avoid sparse warnings.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Merge irq.c and s390_ext.c into irq.c. That way all external interrupt
related functions are together.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Interrupt sources like pfault, sclp, dasd_diag and virtio all use the
service signal external interrupt subclass mask in control register 0
to enable and disable the corresponding interrupt.
Because no reference counting is implemented each subsystem thinks it
is the only user of subclass and sets and clears the bit like it wants.
This leads to case that unloading the dasd diag module under z/VM
causes both sclp and pfault interrupts to be masked. The result will
be locked up system sooner or later.
Fix this by introducing a new way to set (register) and clear
(unregister) the service signal subclass mask bit in cr0.
Also convert all drivers.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

pfault, dasd diag and virtio all use the same external interrupt number.
The respective interrupt handlers decide by the subcode if they are
meant to handle the interrupt.
Counting is currently done before looking at the subcode which means
each handler counts an interrupt even if it is not handling it.
Fix this by moving the kstat code after the code which looks at the
subcode.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Up to now /proc/interrupts only has statistics for external and i/o
interrupts but doesn't split up them any further.
This patch adds a line for every single interrupt source so that it
is possible to easier tell what the machine is/was doing.
Part of the output now looks like this;

           CPU0       CPU2       CPU4
EXT:       3898       4232       2305
I/O:        782        315        245
CLK:       1029       1964        727   [EXT] Clock Comparator
IPI:       2868       2267       1577   [EXT] Signal Processor
TMR:          0          0          0   [EXT] CPU Timer
TAL:          0          0          0   [EXT] Timing Alert
PFL:          0          0          0   [EXT] Pseudo Page Fault
[...]
NMI:          0          1          1   [NMI] Machine Checks
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Read external interrupts parameters from the lowcore in the first
level interrupt handler in entry[64].S.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The one big missing feature in s390-virtio was hotplugging. This is no more.
This patch implements hotplug add support, so you can on the fly add new devices
in the guest.

Keep in mind that this needs a patch for qemu to actually leverage the
functionality.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

Currenty the ext_param field only distinguishes between "config change" and
"vring interrupt". We can do a lot more with it though, so let's enable a
full byte of possible values and constants to #defines while at it.
Signed-off-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

Use asm offsets to make sure the offset defines to struct _lowcore and
its layout don't get out of sync.
Also add a BUILD_BUG_ON() which checks that the size of the structure
is sane.
And while being at it change those sites which use odd casts to access
the current lowcore. These should use S390_lowcore instead.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Use a console_initcall() to initialize the s390 virtio console and
clean up s390 console initialization in setup.c.
Signed-off-by: NHendrik Brueckner <brueckner@linux.vnet.ibm.com>
Tested-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

This replaces find_vq/del_vq with find_vqs/del_vqs virtio operations,
and updates all drivers. This is needed for MSI support, because MSI
needs to know the total number of vectors upfront.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (+ lguest/9p compile fixes)

Add a linked list of all virtqueues for a virtio device: this helps for
debugging and is also needed for upcoming interface change.

Also, add a "name" field for clearer debug messages.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Replace s390_root_dev_register() with root_device_register() etc.

[Includes fix from Cornelia Huck]
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

This patch implements config_changed for the s390 virtio transport.

We use the least significant bit of the interrupt parameter field
to decide, if this interrupt should call the virtio virtqueue callback
or the config_changed callback.

This method is compatible with old host and guest code. Old 64 bit guests
will not check the bit and trigger a harmless additional vring_interrupt
call. Old host code will never set this bit, this is also safe.

This patch also takes care of a potential future 31 bit virtio transport
for s390. On 31 bit _LC_PFAULT_INTPARM and __LC_EXT_PARAMS are identical.
We exploit the alignment of the token and fold the change bit into the
lsb of the token itself.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

This allows each virtio user to hand in the alignment appropriate to
their virtio_ring structures.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Acked-by: NChristian Borntraeger <borntraeger@de.ibm.com>

This doesn't really matter, since s390 pagesize is 4k anyway.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Acked-by: NChristian Borntraeger <borntraeger@de.ibm.com>

The current virtio model on s390 has the descriptor page above the main
memory. The guest virtio detection will oops if the mem= parameter is
used to reduce/change the memory size.
We have to use real_memory_size instead of max_pfn to detect the virtio
descriptor pages.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>

No need to define a static device for the kvm_s390 root device,
just use s390_root_dev_register().

This is needed for the bus_id rework
Acked-by: NCarsten Otte <cotte@de.ibm.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Fix these two false positive warnings:

WARNING: vmlinux.o(.text+0x2e1cc4): Section mismatch in reference from the function s390_virtio_console_init() to the function .init.text:early_put_chars()
The function s390_virtio_console_init() references
the function __init early_put_chars().
This is often because s390_virtio_console_init lacks a __init
annotation or the annotation of early_put_chars is wrong.

WARNING: vmlinux.o(.text+0x2e1cd0): Section mismatch in reference from the function s390_virtio_console_init() to the function .init.text:virtio_cons_early_init()
The function s390_virtio_console_init() references
the function __init virtio_cons_early_init().
This is often because s390_virtio_console_init lacks a __init
annotation or the annotation of virtio_cons_early_init is wrong.

Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

To prepare for virtio_ring transport feature bits, hook in a call in
all the users to manipulate them.  This currently just clears all the
bits, since it doesn't understand any features.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Rather than explicitly handing the features to the lower-level, we just
hand the virtio_device and have it set the features.  This make it clear
that it has the chance to manipulate the features of the device at this
point (and that all feature negotiation is already done).
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

This patch enables virtio_console as the default console on kvm for
s390. We currently use the same notify hack as lguest for early
console output. I will try to address this for lguest and s390 later.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Anthony Liguori points out that three different transports use the virtio code,
but each one keeps its own counter to set the virtio_device's index field.  In
theory (though not in current practice) this means that names could be
duplicated, and that risk grows as more transports are created.

So we move the selection of the unique virtio_device.index into the common code
in virtio.c, which has the side-benefit of removing duplicate code.

The only complexity is that lguest and S/390 use the index to uniquely identify
the device in case of catastrophic failure before register_virtio_device() is
called: now we use the offset within the descriptor page as a unique identifier
for the printks.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Chris Lalancette <clalance@redhat.com>
Cc: Anthony Liguori <anthony@codemonkey.ws>

Fix kvm compile error:

Commit c45a6816
(virtio: explicit advertisement of driver features)
and commit e976a2b9
(s390: KVM guest: virtio device support, and kvm hypercalls)
don't like each other:

  CC      drivers/s390/kvm/kvm_virtio.o
drivers/s390/kvm/kvm_virtio.c:224: error: unknown field 'feature' specified in initializer
drivers/s390/kvm/kvm_virtio.c:224: warning: initialization from incompatible pointer type
make[3]: *** [drivers/s390/kvm/kvm_virtio.o] Error 1

Cc: Adrian Bunk <bunk@kernel.org>
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Acked-by: NCarsten Otte <cotte@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Convert s390 to SPARSEMEM and SPARSEMEM_VMEMMAP. We do a select
of SPARSEMEM_VMEMMAP since it is configurable. This is because
SPARSEMEM without SPARSEMEM_VMEMMAP gives us a hell of broken
include dependencies that I don't want to fix.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

This patch implements kvm guest kernel support for paravirtualized devices
and contains two parts:
o a basic virtio stub using virtio_ring and external interrupts and hypercalls
o full hypercall implementation in kvm_para.h

Currently we dont have PCI on s390. Making virtio_pci usable for s390 seems
more complicated that providing an own stub. This virtio stub is similar to
the lguest one, the memory for the descriptors and the device detection is made
via additional mapped memory on top of the guest storage. We use an external
interrupt with extint code 0x2603 for host->guest notification.

The hypercall definition uses the diag instruction for issuing a hypercall. The
parameters are written in R2-R7, the hypercall number is written in R1. This is
similar to the system call ABI (svc) which can use R1 for the number and R2-R6
for the parameters.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Acked-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NCarsten Otte <cotte@de.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>