Commit Graph

193 Commits

Author SHA1 Message Date
Konrad Rzeszutek Wilk e6197acc72 xen/irq: Export 'xen_pirq_from_irq' function.
We need this to find the real Xen PIRQ value for a device
that requests an MSI or MSI-X. In the past we used
'xen_gsi_from_irq' since that function would return
an Xen PIRQ or GSI depending on the provided IRQ. Now that
we have seperated that we need to use the correct
function.

[v2: Deal with rebase on stable/irq.cleanup]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-04-14 11:17:55 -04:00
Konrad Rzeszutek Wilk c7c2c3a286 xen/irq: Add support to check if IRQ line is shared with other domains.
We do this via the PHYSDEVOP_irq_status_query support hypervisor call.
We will get a positive value if another domain has binded its
PIRQ to the specified GSI (IRQ line).

[v2: Deal with v2.6.37-rc1 rebase fallout]
[v3: Deal with stable/irq.cleanup fallout]
[v4: xen_ignore_irq->xen_test_irq_shared]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-04-14 11:17:54 -04:00
Konrad Rzeszutek Wilk beafbdc1df xen/irq: Check if the PCI device is owned by a domain different than DOMID_SELF.
We check if there is a domain owner for the PCI device. In case of failure
(meaning no domain has registered for this device) we make DOMID_SELF the owner.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
[v2: deal with rebasing on v2.6.37-1]
[v3: deal with rebasing on stable/irq.cleanup]
[v4: deal with rebasing on stable/irq.ween_of_nr_irqs]
[v5: deal with rebasing on v2.6.39-rc3]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: Xiantao Zhang <xiantao.zhang@intel.com>
2011-04-14 11:17:36 -04:00
Linus Torvalds 16ad56972c Merge branch 'stable/bug-fixes-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/bug-fixes-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen: Allow PV-OPS kernel to detect whether XSAVE is supported
  xen: just completely disable XSAVE
  xen/debug: Don't be so verbose with WARN on 1-1 mapping errors.
  xen: events: fix error checks in bind_*_to_irqhandler()
2011-04-11 20:01:04 -07:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Nicolas Kaiser 361ae8cb57 xen: events: fix error checks in bind_*_to_irqhandler()
Checking 'irq < 0' doesn't work when 'irq' is unsigned.

The assigned bind_evtchn_to_irq() and bind_virq_to_irq()
return int, so using int appears appropriate.

Signed-off-by: Nicolas Kaiser <nikai@nikai.net>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-30 15:37:04 -04:00
Thomas Gleixner a3b975c49e xen: Use new irq_move functions
These functions take irq_data as an argument and avoid a redundant
lookup in the sparse irq case.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-29 14:48:15 +02:00
Thomas Gleixner c442b8068f xen: Cleanup genirq namespace
Converted with coccinelle.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-03-29 14:48:15 +02:00
Linus Torvalds 5a39837f76 Merge branches 'stable/irq.fairness' and 'stable/irq.ween_of_nr_irqs' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/irq.fairness' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen: events: Remove redundant clear of l2i at end of round-robin loop
  xen: events: Make round-robin scan fairer by snapshotting each l2 word once only
  xen: events: Clean up round-robin evtchn scan.
  xen: events: Make last processed event channel a per-cpu variable.
  xen: events: Process event channels notifications in round-robin order.

* 'stable/irq.ween_of_nr_irqs' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen: events: Fix compile error if CONFIG_SMP is not defined.
  xen: events: correct locking in xen_irq_from_pirq
  xen: events: propagate irq allocation failure instead of panicking
  xen: events: do not workaround too-small nr_irqs
  xen: events: remove use of nr_irqs as upper bound on number of pirqs
  xen: events: dynamically allocate irq info structures
  xen: events: maintain a list of Xen interrupts
  xen: events: push setup of irq<->{evtchn,ipi,virq,pirq} maps into irq_info init functions
  xen: events: turn irq_info constructors into initialiser functions
  xen: events: use per-cpu variable for cpu_evtchn_mask
  xen: events: refactor GSI pirq bindings functions
  xen: events: rename restore_cpu_pirqs -> restore_pirqs
  xen: events: remove unused public functions
  xen: events: fix xen_map_pirq_gsi error return
  xen: events: simplify comment
  xen: events: separate two unrelated halves of if condition

Fix up trivial conflicts in drivers/xen/events.c
2011-03-17 18:27:49 -07:00
Linus Torvalds 7a6362800c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1480 commits)
  bonding: enable netpoll without checking link status
  xfrm: Refcount destination entry on xfrm_lookup
  net: introduce rx_handler results and logic around that
  bonding: get rid of IFF_SLAVE_INACTIVE netdev->priv_flag
  bonding: wrap slave state work
  net: get rid of multiple bond-related netdevice->priv_flags
  bonding: register slave pointer for rx_handler
  be2net: Bump up the version number
  be2net: Copyright notice change. Update to Emulex instead of ServerEngines
  e1000e: fix kconfig for crc32 dependency
  netfilter ebtables: fix xt_AUDIT to work with ebtables
  xen network backend driver
  bonding: Improve syslog message at device creation time
  bonding: Call netif_carrier_off after register_netdevice
  bonding: Incorrect TX queue offset
  net_sched: fix ip_tos2prio
  xfrm: fix __xfrm_route_forward()
  be2net: Fix UDP packet detected status in RX compl
  Phonet: fix aligned-mode pipe socket buffer header reserve
  netxen: support for GbE port settings
  ...

Fix up conflicts in drivers/staging/brcm80211/brcmsmac/wl_mac80211.c
with the staging updates.
2011-03-16 16:29:25 -07:00
Linus Torvalds 5f6fb45466 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (116 commits)
  x86: Enable forced interrupt threading support
  x86: Mark low level interrupts IRQF_NO_THREAD
  x86: Use generic show_interrupts
  x86: ioapic: Avoid redundant lookup of irq_cfg
  x86: ioapic: Use new move_irq functions
  x86: Use the proper accessors in fixup_irqs()
  x86: ioapic: Use irq_data->state
  x86: ioapic: Simplify irq chip and handler setup
  x86: Cleanup the genirq name space
  genirq: Add chip flag to force mask on suspend
  genirq: Add desc->irq_data accessor
  genirq: Add comments to Kconfig switches
  genirq: Fixup fasteoi handler for oneshot mode
  genirq: Provide forced interrupt threading
  sched: Switch wait_task_inactive to schedule_hrtimeout()
  genirq: Add IRQF_NO_THREAD
  genirq: Allow shared oneshot interrupts
  genirq: Prepare the handling of shared oneshot interrupts
  genirq: Make warning in handle_percpu_event useful
  x86: ioapic: Move trigger defines to io_apic.h
  ...

Fix up trivial(?) conflicts in arch/x86/pci/xen.c due to genirq name
space changes clashing with the Xen cleanups.  The set_irq_msi() had
moved to xen_bind_pirq_msi_to_irq().
2011-03-15 19:23:40 -07:00
Konrad Rzeszutek Wilk 44626e4a3b xen: events: Fix compile error if CONFIG_SMP is not defined.
drivers/xen/events.c:396: error: 'struct irq_data' has no member named 'affinity'

Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-15 16:40:33 -04:00
Linus Torvalds 27d2a8b97e Merge branches 'stable/ia64', 'stable/blkfront-cleanup' and 'stable/cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/ia64' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen: ia64 build broken due to "xen: switch to new schedop hypercall by default."

* 'stable/blkfront-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen: Union the blkif_request request specific fields

* 'stable/cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen: annotate functions which only call into __init at start of day
  xen p2m: annotate variable which appears unused
  xen: events: mark cpu_evtchn_mask_p as __refdata
2011-03-15 10:49:16 -07:00
Ian Campbell a7b807ce8c xen: events: correct locking in xen_irq_from_pirq
One of those spin_lock() calls should be an unlock...

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-14 10:53:02 -04:00
Ian Campbell 7bee976822 xen: events: propagate irq allocation failure instead of panicking
Running out of IRQs need not be fatal to the machine as a whole.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:48:45 -05:00
Ian Campbell 6cb9bf3aaf xen: events: do not workaround too-small nr_irqs
With the introduction of e7bcecb7b1 "genirq: Make nr_irqs runtime expandable"
nr_irqs can grow as necessary to accommodate our allocation requests.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:48:44 -05:00
Ian Campbell 69c358ce37 xen: events: remove use of nr_irqs as upper bound on number of pirqs
There isn't really much relationship between the two, other than
nr_irqs often being the larger of the two.

Allows us to remove a nr_irqs sized array, the only users of this
array are MSI setup and restore, neither of which are particularly
performance critical.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:48:43 -05:00
Ian Campbell ca62ce8cde xen: events: dynamically allocate irq info structures
Removes nr_irq sized array allocation at start of day.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:48:42 -05:00
Ian Campbell 6cb6537d34 xen: events: maintain a list of Xen interrupts
In a PVHVM kernel not all interrupts are Xen interrupts (APIC interrupts can also be present).

Currently we get away with walking over all interrupts because the
lookup in the irq_info array simply returns IRQT_UNBOUND and we ignore
it. However this array will be going away in a future patch so we need
to manually track which interrupts have been allocated by the Xen
events infrastructure.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:48:41 -05:00
Ian Campbell 3d4cfa3736 xen: events: push setup of irq<->{evtchn,ipi,virq,pirq} maps into irq_info init functions
Encapsulate setup of XXX_to_irq array in the relevant
xen_irq_info_*_init function.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:48:40 -05:00
Ian Campbell 9158c3588a xen: events: turn irq_info constructors into initialiser functions
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:48:39 -05:00
Ian Campbell cb60d11427 xen: events: use per-cpu variable for cpu_evtchn_mask
I can't see any reason why it isn't already.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:48:38 -05:00
Ian Campbell f4d0635bf8 xen: events: refactor GSI pirq bindings functions
Following the example set by xen_allocate_pirq_msi and
xen_bind_pirq_msi_to_irq:

xen_allocate_pirq becomes xen_allocate_pirq_gsi and now only allocates
a pirq number and does not bind it.

xen_map_pirq_gsi becomes xen_bind_pirq_gsi_to_irq and binds an
existing pirq.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:48:37 -05:00
Ian Campbell 0a85226ff2 xen: events: rename restore_cpu_pirqs -> restore_pirqs
There is nothing per-cpu about this function.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:48:36 -05:00
Ian Campbell 76465b2daf xen: events: remove unused public functions
I was unable to find any user of these functions in either the
functionality pending for 2.6.39 or the xen/next-2.6.32 branch of
xen.git

An exception to this was xen_gsi_from_irq which did appear to be used
in xen/next-2.6.32's pciback. However in the 2.6.39 version of pciback
xen_pirq_from_irq is, correctly AFAICT, used instead.

Only a minority of functions in events.h use "extern" so drop it from
those places for consistency.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:48:35 -05:00
Ian Campbell a0e181167e xen: events: fix xen_map_pirq_gsi error return
Fix initial value of irq so that first goto out (if pirq or gsi
arguments are too large) actually returns an error.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:48:34 -05:00
Ian Campbell 653378acdd xen: events: simplify comment
It is never valid assume any particular relationship between a Xen
PIRQ number and and Linux IRQ number so there is no need to hedge when
saying so.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:48:33 -05:00
Ian Campbell be49472f04 xen: events: separate two unrelated halves of if condition
Clarifies which bit the comment applies to.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:48:32 -05:00
Keir Fraser 3b7bcdf282 xen: events: Remove redundant clear of l2i at end of round-robin loop
Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[ijc: forward ported from linux-2.6.18-xen.hg 991:9ba6d9f3fbc0]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:47:59 -05:00
Keir Fraser 24b51c2f2d xen: events: Make round-robin scan fairer by snapshotting each l2 word once only
(except for starting l2 word, which we scan in two parts).

Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[ijc: forward ported from linux-2.6.18-xen.hg 990:427276ac595d]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:47:58 -05:00
Keir Fraser ada6814c87 xen: events: Clean up round-robin evtchn scan.
Also fixes a couple of boundary cases.

Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[ijc: forward ported from linux-2.6.18-xen.hg 988:c88a02a22a05]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:47:57 -05:00
Ian Campbell f1f4a323d4 xen: events: Make last processed event channel a per-cpu variable.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[ijc: forward ported from linux-2.6.18-xen.hg 325:b2768401db94]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:47:56 -05:00
Scott Rixner ab7f863e41 xen: events: Process event channels notifications in round-robin order.
Avoids fairness issue resulting from domain 0 processing lowest
numbered event channel first.

Fixes bug #1115 "Event channel port scanning unfair".

Bugzilla: http://bugzilla.xensource.com/bugzilla/show_bug.cgi?id=1115
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
[ijc: forward ported from linux-2.6.18-xen.hg 324:7fe1c6d02a2b
 various variables have different names in this tree:
  l1  -> pending_words
  l2  -> pending_bits
  l1i -> word_idx
  l2i -> bit_idx]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:47:55 -05:00
Ian Campbell 71eef7d1e3 xen: events: remove dom0 specific xen_create_msi_irq
The function name does not distinguish it from xen_allocate_pirq_msi
(which operates on domU and pvhvm domains rather than dom0).

Hoist domain 0 specific functionality up into the only caller leaving
functionality common to all guest types in xen_bind_pirq_msi_to_irq.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:44:45 -05:00
Ian Campbell ca1d8fe952 xen: events: use xen_bind_pirq_msi_to_irq from xen_create_msi_irq
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:44:44 -05:00
Ian Campbell f420e010ed xen: events: push set_irq_msi down into xen_create_msi_irq
Makes the tail end of this function look even more like
xen_bind_pirq_msi_to_irq.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:44:43 -05:00
Ian Campbell 2e55288f63 xen: events: update pirq_to_irq in xen_create_msi_irq
I don't think this was a deliberate ommision.

Makes the tail end of this function look even more like
xen_bind_pirq_msi_to_irq.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:44:42 -05:00
Ian Campbell 8135591e90 xen: events: refactor xen_create_msi_irq slightly
Calling PHYSDEVOP_map_pirq earlier simplifies error handling and
starts to make the tail end of this function look like
xen_bind_pirq_msi_to_irq.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:44:41 -05:00
Ian Campbell bf480d952b xen: events: separate MSI PIRQ allocation from PIRQ binding to IRQ
Split the binding aspect of xen_allocate_pirq_msi out into a new
xen_bind_pirq_to_irq function.

In xen_hvm_setup_msi_irq when allocating a pirq write the MSI message
to signal the PIRQ as soon as the pirq is obtained. There is no way to
free the pirq back so if the subsequent binding to an IRQ fails we
want to ensure that we will reuse the PIRQ next time rather than leak
it.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:44:40 -05:00
Ian Campbell 5cad61a6ba xen: events: assume PHYSDEVOP_get_free_pirq exists
The find_unbound_pirq is called only from xen_allocate_pirq_msi and
only if alloc_pirq is true. The only caller which does this is
xen_hvm_setup_msi_irqs. The use of this function is gated, in
pci_xen_hvm_init, on XENFEAT_hvm_pirqs.

The PHYSDEVOP_get_free_pirq interfaces was added to the hypervisor in
22410:be96f6058c05 while XENFEAT_hvm_pirqs was added a couple of
minutes prior in 22409:6663214f06ac. Therefore we do not need to
concern ourselves with hypervisors which support XENFEAT_hvm_pirqs but
not PHYSDEVOP_get_free_pirq.

This eliminates the fallback path in find_unbound_pirq which walks to
pirq_to_irq array looking for a free pirq. Unlike the
PHYSDEVOP_get_free_pirq interface this fallback only looks up a free
pirq but does not reserve it. Removing this fallback will simplify
locking in the future.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:44:39 -05:00
Ian Campbell 4b41df7f6e xen: events: return irq from xen_allocate_pirq_msi
consistent with other similar functions.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:44:37 -05:00
Ian Campbell bb5d079aef xen: events: drop XEN_ALLOC_IRQ flag to xen_allocate_pirq_msi
All callers pass this flag so it is pointless.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:44:35 -05:00
Ian Campbell ae1635b05f xen: events: do not leak IRQ from xen_allocate_pirq_msi when no pirq available.
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: xen-devel@lists.xensource.com
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-10 14:44:34 -05:00
Konrad Rzeszutek Wilk 1aa0b51a03 xen/irq: Cleanup up the pirq_to_irq for DomU PV PCI passthrough guests as well.
We only did this for PV guests that are xen_initial_domain() but
there is not reason not to do this for other cases. The other
case is only exercised when you pass in a PCI device to a PV guest
_and_ the device in question.

Reviewed-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-03 12:02:22 -05:00
Thomas Gleixner 676dc3cf5b xen: Use IRQF_FORCE_RESUME
Mark the IRQF_NO_SUSPEND interrupts IRQF_FORCE_RESUME and remove the extra
walk through the interrupt descriptors.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-03 12:02:21 -05:00
Ian Campbell aa673c1cb3 xen: Fix compile error introduced by "switch to new irq_chip functions"
drivers/xen/events.c: In function 'ack_pirq':
drivers/xen/events.c:568: error: implicit declaration of function 'irq_move_irq'

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-03 12:00:30 -05:00
Thomas Gleixner c9e265e030 xen: Switch to new irq_chip functions
Convert Xen to the new irq_chip functions. Brings us closer to enable
CONFIG_GENERIC_HARDIRQS_NO_DEPRECATED

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-03 12:00:29 -05:00
Thomas Gleixner 149f256f8c xen: Remove stale irq_chip.end
irq_chip.end got obsolete with the removal of __do_IRQ()

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-03 12:00:28 -05:00
Ian Campbell 7214610475 xen: events: do not free legacy IRQs
c514d00c8057 "xen: events: add xen_allocate_irq_{dynamic, gsi} and
xen_free_irq" correctly avoids reallocating legacy IRQs (which are
managed by the arch core) but erroneously did not prevent them being
freed.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-03-03 12:00:27 -05:00
Ian Campbell 89911501f3 xen: events: allocate GSIs and dynamic IRQs from separate IRQ ranges.
There are three cases which we need to care about, PV guest, PV domain
0 and HVM guest.

The PV guest case is simple since it has no access to ACPI or real
APICs and therefore has no GSIs therefore we simply dynamically
allocate all IRQs. The potentially interesting case here is PIRQ type
event channels associated with passed through PCI devices. However
even in this case the guest has no direct interaction with the
physical GSI since that happens in the PCI backend.

The PV domain 0 and HVM guest cases are actually the same. In domain 0
case the kernel sees the host ACPI and GSIs (although it only sees the
APIC indirectly via the hypervisor) and in the HVM guest case it sees
the virtualised ACPI and emulated APICs. In these cases we start
allocating dynamic IRQs at nr_irqs_gsi so that they cannot clash with
any GSI.

Currently xen_allocate_irq_dynamic starts at nr_irqs and works
backwards looking for a free IRQ in order to (try and) avoid clashing
with GSIs used in domain 0 and in HVM guests. This change avoids that
although we retain the behaviour of allowing dynamic IRQs to encroach
on the GSI range if no suitable IRQs are available since a future IRQ
clash is deemed preferable to failure right now.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
2011-03-03 12:00:21 -05:00
Ian Campbell c9df1ce585 xen: events: add xen_allocate_irq_{dynamic, gsi} and xen_free_irq
This is neater than open-coded calls to irq_alloc_desc_at and
irq_free_desc.

No intended behavioural change.

Note that we previously were not checking the return value of
irq_alloc_desc_at which would be failing for GSI<NR_IRQS_LEGACY
because the core architecture code has already allocated those for
us. Hence the additional check against NR_IRQS_LEGACY in
xen_allocate_irq_gsi.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
2011-03-03 11:56:59 -05:00
Ian Campbell cbf6aa89fc xen:events: move find_unbound_irq inside CONFIG_PCI_MSI
The only caller is xen_allocate_pirq_msi which is also under this
ifdef so this fixes:
    drivers/xen/events.c:377: warning: 'find_unbound_pirq' defined but not used
when CONFIG_PCI_MSI=n

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
2011-03-03 11:56:58 -05:00
Ian Campbell 2e820f58f7 xen/irq: implement bind_interdomain_evtchn_to_irqhandler for backend drivers
Impact: new Xen-internal API

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-02-28 09:39:37 -05:00
Ian Campbell b052181a98 xen: events: mark cpu_evtchn_mask_p as __refdata
This variable starts out pointing at init_evtchn_mask which is marked
__initdata but is set to point to a non-init data region in xen_init_IRQ
which is itself an __init function so this is safe.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Tested-and-acked-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-02-11 14:46:25 -05:00
Linus Torvalds 9f99a2f0e4 Merge branch 'stable/bug-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/bug-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/event: validate irq before get evtchn by irq
  xen/fb: fix potential memory leak
  xen/fb: fix xenfb suspend/resume race.
  xen: disable ACPI NUMA for PV guests
  xen/irq: Cleanup the find_unbound_irq
2011-01-10 08:48:46 -08:00
Joe Jin 110e7c7e4f xen/event: validate irq before get evtchn by irq
When retrieving the event channel number from irq, the irq
number may not be valid under some conditions.

So far that can be when we suspend/resume and irq ends with -1.
Validate and return sanitized irq and provide diagnostics information.

[v3: added unlikely on the WARN path]
[v2: reworded the commit message]
Signed-off-by: Joe Jin <joe.jin@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Gurudas Pai <gurudas.pai@oracle.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
2011-01-10 10:46:32 -05:00
Christoph Lameter b2e4ae6975 xen: Use this_cpu_inc_return
__this_cpu_inc_return reduces code and simplifies code.

Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
2010-12-17 15:18:05 +01:00
Christoph Lameter 780f36d8b3 xen: Use this_cpu_ops
Use this_cpu_ops to reduce code size and simplify things in various places.

V3->V4:
	Move instance of this_cpu_inc_return to a later patchset so that
	this patch can be applied without infrastructure changes.

Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2010-12-17 15:07:19 +01:00
Konrad Rzeszutek Wilk d1b758ebc2 xen/irq: Cleanup the find_unbound_irq
The "find_unbound_irq" is a bit unusual - it allocates
virtual IRQ (event channels) in reverse order. This means
starting at the "top" of the available IRQs (nr_irqs) down
to the GSI/MSI IRQs (nr_irqs_gsi). Lets document this and
also make the variables easier to understand.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-12-09 16:02:35 -05:00
Linus Torvalds 11e8896474 Merge branch '2.6.37-rc4-pvhvm-fixes' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm
* '2.6.37-rc4-pvhvm-fixes' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm:
  xen: unplug the emulated devices at resume time
  xen: fix save/restore for PV on HVM guests with pirq remapping
  xen: resume the pv console for hvm guests too
  xen: fix MSI setup and teardown for PV on HVM guests
  xen: use PHYSDEVOP_get_free_pirq to implement find_unbound_pirq
2010-12-03 11:30:57 -08:00
Jeremy Fitzhardinge 29dcbc5c25 xen: allocate irq descs on any NUMA node
Allocate irq descs on any NUMA node (we don't care) rather than
specifically node 0, which may not exist.

(At the moment NUMA is meaningless within a domain, so any info
the kernel has is just from an SRAT table we haven't suppressed/disabled.)

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-12-02 16:14:27 -08:00
Stefano Stabellini 9a069c33c5 xen: fix save/restore for PV on HVM guests with pirq remapping
Re-map and re-bind all the pirqs at resume time.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2010-12-02 14:40:50 +00:00
Stefano Stabellini af42b8d12f xen: fix MSI setup and teardown for PV on HVM guests
When remapping MSIs into pirqs for PV on HVM guests, qemu is responsible
for doing the actual mapping and unmapping.
We only give qemu the desired pirq number when we ask to do the mapping
the first time, after that we should be reading back the pirq number
from qemu every time we want to re-enable the MSI.

This fixes a bug in xen_hvm_setup_msi_irqs that manifests itself when
trying to enable the same MSI for the second time: the old MSI to pirq
mapping is still valid at this point but xen_hvm_setup_msi_irqs would
try to assign a new pirq anyway.
A simple way to reproduce this bug is to assign an MSI capable network
card to a PV on HVM guest, if the user brings down the corresponding
ethernet interface and up again, Linux would fail to enable MSIs on the
device.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2010-12-02 14:34:25 +00:00
Stefano Stabellini e5fc734541 xen: use PHYSDEVOP_get_free_pirq to implement find_unbound_pirq
Use the new hypercall PHYSDEVOP_get_free_pirq to ask Xen to allocate a
pirq. Remove the unsupported PHYSDEVOP_get_nr_pirqs hypercall to get the
amount of pirq available.

This fixes find_unbound_pirq that otherwise would return a number
starting from nr_irqs that might very well be out of range in Xen.

The symptom of this bug is that when you passthrough an MSI capable pci
device to a PV on HVM guest, Linux would fail to enable MSIs on the
device.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2010-12-02 14:28:22 +00:00
Konrad Rzeszutek Wilk 1233471572 xen/events: Use PIRQ instead of GSI value when unmapping MSI/MSI-X irqs.
When we allocate a vector for MSI/MSI-X we save away the PIRQ, and the
vector value. When we unmap (de-allocate) the MSI/MSI-X vector(s) we
need to provide the PIRQ and the vector value. What we did instead
was to provide the GSI (which was zero) and the vector value, and we
got these unhappy error messages:

(XEN) irq.c:1575: dom0: pirq 0 not mapped
[    7.733415] unmap irq failed -22

This patches fixes this and we use the PIRQ value instead of the GSI
value.

CC: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-11-22 12:10:34 -08:00
Jeremy Fitzhardinge e04195644e xen/events: use locked set|clear_bit() for cpu_evtchn_mask
The per-cpu event channel masks can be updated unlocked from multiple
CPUs, so use the locked variant.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-11-16 14:58:50 -08:00
Jan Beulich 1c6969ec8e xen/evtchn: clear secondary CPUs' cpu_evtchn_mask[] after restore
To bind all event channels to CPU#0, it is not sufficient to set all
of its cpu_evtchn_mask[] bits; all other CPUs also need to get their
bits cleared. Otherwise, evtchn_do_upcall() will start handling
interrupts on CPUs they're not intended to run on, which can be
particularly bad for per-CPU ones.

[ linux-2.6.18-xen.hg 7de7453dee36 ]

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-11-16 14:58:47 -08:00
Ian Campbell 6903591f31 xen: events: do not unmask event channels on resume
The IRQ core code will take care of disabling and reenabling
interrupts over suspend resume automatically, therefore we do not need
to do this in the Xen event channel code.

The only exception is those event channels marked IRQF_NO_SUSPEND
which the IRQ core ignores. We must unmask these ourselves, taking
care to obey the current IRQ_DISABLED status. Failure check for
IRQ_DISABLED leads to enabling polled only event channels, such as
that associated with the pv spinlocks, which must never be enabled:

[   21.970432] ------------[ cut here ]------------
[   21.970432] kernel BUG at arch/x86/xen/spinlock.c:343!
[   21.970432] invalid opcode: 0000 [#1] SMP
[   21.970432] last sysfs file: /sys/devices/virtual/net/lo/operstate
[   21.970432] Modules linked in:
[   21.970432]
[   21.970432] Pid: 0, comm: swapper Not tainted (2.6.32.24-x86_32p-xen-01034-g787c727 #34)
[   21.970432] EIP: 0061:[<c102e209>] EFLAGS: 00010046 CPU: 3
[   21.970432] EIP is at dummy_handler+0x3/0x7
[   21.970432] EAX: 0000021c EBX: dfc16880 ECX: 0000001a EDX: 00000000
[   21.970432] ESI: dfc02c00 EDI: 00000001 EBP: dfc47e10 ESP: dfc47e10
[   21.970432]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0069
[   21.970432] Process swapper (pid: 0, ti=dfc46000 task=dfc39440 task.ti=dfc46000)
[   21.970432] Stack:
[   21.970432]  dfc47e30 c10a39f0 0000021c 00000000 00000000 dfc16880 0000021c 00000001
[   21.970432] <0> dfc47e40 c10a4f08 0000021c 00000000 dfc47e78 c12240a7 c1839284 c1839284
[   21.970432] <0> 00000200 00000000 00000000 f5720000 c1f3d028 c1f3d02c 00000180 dfc47e90
[   21.970432] Call Trace:
[   21.970432]  [<c10a39f0>] ? handle_IRQ_event+0x5f/0x122
[   21.970432]  [<c10a4f08>] ? handle_percpu_irq+0x2f/0x55
[   21.970432]  [<c12240a7>] ? __xen_evtchn_do_upcall+0xdb/0x15f
[   21.970432]  [<c122481e>] ? xen_evtchn_do_upcall+0x20/0x30
[   21.970432]  [<c1030d47>] ? xen_do_upcall+0x7/0xc
[   21.970432]  [<c102007b>] ? apic_reg_read+0xd3/0x22d
[   21.970432]  [<c1002227>] ? hypercall_page+0x227/0x1005
[   21.970432]  [<c102d30b>] ? xen_force_evtchn_callback+0xf/0x14
[   21.970432]  [<c102da7c>] ? check_events+0x8/0xc
[   21.970432]  [<c102da3b>] ? xen_irq_enable_direct_end+0x0/0x1
[   21.970432]  [<c105e485>] ? finish_task_switch+0x62/0xba
[   21.970432]  [<c14e3f84>] ? schedule+0x808/0x89d
[   21.970432]  [<c1084dc5>] ? hrtimer_start_expires+0x1a/0x22
[   21.970432]  [<c1085154>] ? tick_nohz_restart_sched_tick+0x15a/0x162
[   21.970432]  [<c102f43a>] ? cpu_idle+0x6d/0x6f
[   21.970432]  [<c14db29e>] ? cpu_bringup_and_idle+0xd/0xf
[   21.970432] Code: 5d 0f 95 c0 0f b6 c0 c3 55 66 83 78 02 00 89 e5 5d 0f 95 \
c0 0f b6 c0 c3 55 b2 01 86 10 31 c0 84 d2 89 e5 0f 94 c0 5d c3 55 89 e5 <0f> 0b \
eb fe 55 80 3d 4c ce 84 c1 00 89 e5 57 56 89 c6 53 74 15
[   21.970432] EIP: [<c102e209>] dummy_handler+0x3/0x7 SS:ESP 0069:dfc47e10
[   21.970432] ---[ end trace c0b71f7e12cf3011 ]---

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-11-10 17:19:25 -08:00
Linus Torvalds 18cb657ca1 Merge branch 'stable/xen-pcifront-0.8.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
and branch 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm

* 'for-linus' of git://xenbits.xen.org/people/sstabellini/linux-pvhvm:
  xen: register xen pci notifier
  xen: initialize cpu masks for pv guests in xen_smp_init
  xen: add a missing #include to arch/x86/pci/xen.c
  xen: mask the MTRR feature from the cpuid
  xen: make hvc_xen console work for dom0.
  xen: add the direct mapping area for ISA bus access
  xen: Initialize xenbus for dom0.
  xen: use vcpu_ops to setup cpu masks
  xen: map a dummy page for local apic and ioapic in xen_set_fixmap
  xen: remap MSIs into pirqs when running as initial domain
  xen: remap GSIs as pirqs when running as initial domain
  xen: introduce XEN_DOM0 as a silent option
  xen: map MSIs into pirqs
  xen: support GSI -> pirq remapping in PV on HVM guests
  xen: add xen hvm acpi_register_gsi variant
  acpi: use indirect call to register gsi in different modes
  xen: implement xen_hvm_register_pirq
  xen: get the maximum number of pirqs from xen
  xen: support pirq != irq

* 'stable/xen-pcifront-0.8.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: (27 commits)
  X86/PCI: Remove the dependency on isapnp_disable.
  xen: Update Makefile with CONFIG_BLOCK dependency for biomerge.c
  MAINTAINERS: Add myself to the Xen Hypervisor Interface and remove Chris Wright.
  x86: xen: Sanitse irq handling (part two)
  swiotlb-xen: On x86-32 builts, select SWIOTLB instead of depending on it.
  MAINTAINERS: Add myself for Xen PCI and Xen SWIOTLB maintainer.
  xen/pci: Request ACS when Xen-SWIOTLB is activated.
  xen-pcifront: Xen PCI frontend driver.
  xenbus: prevent warnings on unhandled enumeration values
  xenbus: Xen paravirtualised PCI hotplug support.
  xen/x86/PCI: Add support for the Xen PCI subsystem
  x86: Introduce x86_msi_ops
  msi: Introduce default_[teardown|setup]_msi_irqs with fallback.
  x86/PCI: Export pci_walk_bus function.
  x86/PCI: make sure _PAGE_IOMAP it set on pci mappings
  x86/PCI: Clean up pci_cache_line_size
  xen: fix shared irq device passthrough
  xen: Provide a variant of xen_poll_irq with timeout.
  xen: Find an unbound irq number in reverse order (high to low).
  xen: statically initialize cpu_evtchn_mask_p
  ...

Fix up trivial conflicts in drivers/pci/Makefile
2010-10-28 17:11:17 -07:00
Linus Torvalds 520045db94 Merge branches 'upstream/xenfs' and 'upstream/core' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen
* 'upstream/xenfs' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
  xen/privcmd: make privcmd visible in domU
  xen/privcmd: move remap_domain_mfn_range() to core xen code and export.
  privcmd: MMAPBATCH: Fix error handling/reporting
  xenbus: export xen_store_interface for xenfs
  xen/privcmd: make sure vma is ours before doing anything to it
  xen/privcmd: print SIGBUS faults
  xen/xenfs: set_page_dirty is supposed to return true if it dirties
  xen/privcmd: create address space to allow writable mmaps
  xen: add privcmd driver
  xen: add variable hypercall caller
  xen: add xen_set_domain_pte()
  xen: add /proc/xen/xsd_{kva,port} to xenfs

* 'upstream/core' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen: (29 commits)
  xen: include xen/xen.h for definition of xen_initial_domain()
  xen: use host E820 map for dom0
  xen: correctly rebuild mfn list list after migration.
  xen: improvements to VIRQ_DEBUG output
  xen: set up IRQ before binding virq to evtchn
  xen: ensure that all event channels start off bound to VCPU 0
  xen/hvc: only notify if we actually sent something
  xen: don't add extra_pages for RAM after mem_end
  xen: add support for PAT
  xen: make sure xen_max_p2m_pfn is up to date
  xen: limit extra memory to a certain ratio of base
  xen: add extra pages for E820 RAM regions, even if beyond mem_end
  xen: make sure xen_extra_mem_start is beyond all non-RAM e820
  xen: implement "extra" memory to reserve space for pages not present at boot
  xen: Use host-provided E820 map
  xen: don't map missing memory
  xen: defer building p2m mfn structures until kernel is mapped
  xen: add return value to set_phys_to_machine()
  xen: convert p2m to a 3 level tree
  xen: make install_p2mtop_page() static
  ...

Fix up trivial conflict in arch/x86/xen/mmu.c, and fix the use of
'reserve_early()' - in the new memblock world order it is now
'memblock_x86_reserve_range()' instead. Pointed out by Jeremy.
2010-10-26 18:20:19 -07:00
Jeremy Fitzhardinge 4fe7d5a708 xen: make hvc_xen console work for dom0.
Use the console hypercalls for dom0 console.

[ Impact: Add Xen dom0 console ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-10-22 21:26:01 +01:00
Qing He f731e3ef02 xen: remap MSIs into pirqs when running as initial domain
Implement xen_create_msi_irq to create an msi and remap it as pirq.
Use xen_create_msi_irq to implement an initial domain specific version
of setup_msi_irqs.

Signed-off-by: Qing He <qing.he@intel.com>
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-10-22 21:25:44 +01:00
Jeremy Fitzhardinge 38aa66fcb7 xen: remap GSIs as pirqs when running as initial domain
Implement xen_register_gsi to setup the correct triggering and polarity
properties of a gsi.
Implement xen_register_pirq to register a particular gsi as pirq and
receive interrupts as events.
Call xen_setup_pirqs to register all the legacy ISA irqs as pirqs.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-10-22 21:25:43 +01:00
Stefano Stabellini 809f9267bb xen: map MSIs into pirqs
Map MSIs into pirqs, writing 0 in the MSI vector data field and the pirq
number in the MSI destination id field.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-10-22 21:25:43 +01:00
Stefano Stabellini 3942b740e5 xen: support GSI -> pirq remapping in PV on HVM guests
Disable pcifront when running on HVM: it is meant to be used with pv
guests that don't have PCI bus.

Use acpi_register_gsi_xen_hvm to remap GSIs into pirqs.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-10-22 21:25:42 +01:00
Stefano Stabellini 42a1de56f3 xen: implement xen_hvm_register_pirq
xen_hvm_register_pirq allows the kernel to map a GSI into a Xen pirq and
receive the interrupt as an event channel from that point on.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-10-22 21:25:41 +01:00
Stefano Stabellini 01557baff6 xen: get the maximum number of pirqs from xen
Use PHYSDEVOP_get_nr_pirqs to get the maximum number of pirqs from xen.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-10-22 21:25:40 +01:00
Stefano Stabellini 7a043f119c xen: support pirq != irq
PHYSDEVOP_map_pirq might return a pirq different from what we asked if
we are running as an HVM guest, so we need to be able to support pirqs
that are different from linux irqs.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-10-22 21:25:40 +01:00
Ian Campbell cb52e6d9ed xen: improvements to VIRQ_DEBUG output
* Fix bitmask formatting on 64 bit by specifying correct field widths.

* Output both global and local masked and pending information.

* Indicate in list of pending interrupts whether they are pending in
  the L2, masked globally and/or masked locally.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-10-22 12:57:35 -07:00
Jeremy Fitzhardinge a52521f149 xen: set up IRQ before binding virq to evtchn
Make sure the irq is set up before binding a virq event channel to it.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-10-22 12:57:34 -07:00
Ian Campbell b0097adeec xen: ensure that all event channels start off bound to VCPU 0
All event channels startbound to VCPU 0 so ensure that cpu_evtchn_mask
is initialised to reflect this. Otherwise there is a race after registering an
event channel but before the affinity is explicitly set where the event channel
can be delivered. If this happens then the event channel remains pending in the
L1 (evtchn_pending) array but is cleared in L2 (evtchn_pending_sel), this means
the event channel cannot be reraised until another event channel happens to
trigger the same L2 entry on that VCPU.

sizeof(cpu_evtchn_mask(0))==sizeof(unsigned long*) which is not correct, and
causes only the first 32 or 64 event channels (depending on architecture) to be
initially bound to VCPU0. Use sizeof(struct cpu_evtchn_s) instead.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: stable@kernel.org
2010-10-22 12:57:33 -07:00
Jeremy Fitzhardinge 3588fe2e3f xen/events: change to using fasteoi
Change event delivery to:
 - mask+clear event in the upcall function
 - use handle_fasteoi_irq as the handler
 - unmask in the eoi function (and handle migration)

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-10-22 12:57:21 -07:00
Konrad Rzeszutek Wilk 2c52f8d3f7 x86: xen: Sanitse irq handling (part two)
Thomas Gleixner cleaned up event handling to use the
sparse_irq handling, but the xen-pcifront patches utilized the
old mechanism. This fixes them to work with sparse_irq handling.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-10-18 17:12:38 -04:00
Alex Nixon b5401a96b5 xen/x86/PCI: Add support for the Xen PCI subsystem
The frontend stub lives in arch/x86/pci/xen.c, alongside other
sub-arch PCI init code (e.g. olpc.c).

It provides a mechanism for Xen PCI frontend to setup/destroy
legacy interrupts, MSI/MSI-X, and PCI configuration operations.

[ Impact: add core of Xen PCI support ]
[ v2: Removed the IOMMU code and only focusing on PCI.]
[ v3: removed usage of pci_scan_all_fns as that does not exist]
[ v4: introduced pci_xen value to fix compile warnings]
[ v5: squished fixes+features in one patch, changed Reviewed-by to Ccs]
[ v7: added Acked-by]
Signed-off-by: Alex Nixon <alex.nixon@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Qing He <qing.he@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org
2010-10-18 10:49:35 -04:00
Konrad Rzeszutek Wilk 15ebbb82ba xen: fix shared irq device passthrough
In driver/xen/events.c, whether bind_pirq is shareable or not is
determined by desc->action is NULL or not. But in __setup_irq,
startup(irq) is invoked before desc->action is assigned with
new action. So desc->action in startup_irq is always NULL, and
bind_pirq is always not shareable. This results in pt_irq_create_bind
failure when passthrough a device which shares irq to other devices.

This patch doesn't use probing_irq to determine if pirq is shareable
or not, instead set shareable flag in irq_info according to trigger
mode in xen_allocate_pirq. Set level triggered interrupts shareable.
Thus use this flag to set bind_pirq flag accordingly.

[v2: arch/x86/xen/pci.c no more, so file skipped]

Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-10-18 10:49:29 -04:00
Konrad Rzeszutek Wilk d9a8814f27 xen: Provide a variant of xen_poll_irq with timeout.
The 'xen_poll_irq_timeout' provides a method to pass in
the poll timeout for IRQs if requested. We also export
those two poll functions as Xen PCI fronted uses them.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-10-18 10:49:28 -04:00
Konrad Rzeszutek Wilk 3a69e9165a xen: Find an unbound irq number in reverse order (high to low).
In earlier Xen Linux kernels, the IRQ mapping was a straight 1:1 and the
find_unbound_irq started looking around 256 for open IRQs and up. IRQs
from 0 to 255 were reserved for PCI devices.  Previous to this patch,
the 'find_unbound_irq'  started looking at get_nr_hw_irqs() number.
For privileged  domain where the ACPI information is available that
returns the upper-bound of what the GSIs. For non-privileged PV domains,
where ACPI is no-existent the get_nr_hw_irqs() reports the IRQ_LEGACY (16).
With PCI passthrough enabled, and with PCI cards that have IRQs pinned
to a higher number than 16 we collide with previously allocated IRQs.
Specifically the PCI IRQs collide with the IPI's for Xen functions
(as they are allocated earlier).
For example:

00:00.11 USB Controller: ATI Technologies Inc SB700 USB OHCI1 Controller (prog-if 10 [OHCI])
	...
	Interrupt: pin A routed to IRQ 18

[root@localhost ~]# cat /proc/interrupts | head
           CPU0       CPU1       CPU2
 16:      38186          0          0   xen-dyn-virq      timer0
 17:        149          0          0   xen-dyn-ipi       spinlock0
 18:        962          0          0   xen-dyn-ipi       resched0

and when the USB controller is loaded, the kernel reports:
IRQ handler type mismatch for IRQ 18
current handler: resched0

One way to fix this is to reverse the logic when looking for un-used
IRQ numbers and start with the highest available number. With that,
we would get:

           CPU0       CPU1       CPU2
... snip ..
292:         35          0          0   xen-dyn-ipi       callfunc0
293:       3992          0          0   xen-dyn-ipi       resched0
294:        224          0          0   xen-dyn-ipi       spinlock0
295:      57183          0          0   xen-dyn-virq      timer0
NMI:          0          0          0   Non-maskable interrupts
.. snip ..

And interrupts for PCI cards are now accessible.

This patch also includes the fix, found by Ian Campbell, titled
"xen: fix off-by-one error in find_unbound_irq."

[v2: Added an explanation in the code]
[v3: Rebased on top of tip/irq/core]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-10-18 10:49:10 -04:00
Jeremy Fitzhardinge 3b32f574a0 xen: statically initialize cpu_evtchn_mask_p
Sometimes cpu_evtchn_mask_p can get used early, before it has been
allocated.  Statically initialize it with an initdata version to catch
any early references.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-10-18 10:41:44 -04:00
Gerd Hoffmann 1a60d05f40 xen: set pirq name to something useful.
Impact: cleanup

Make pirq show useful information in /proc/interrupts

[v2: Removed the parts for arch/x86/xen/pci.c ]

Signed-off-by: Gerd Hoffmann <kraxel@xeni.home.kraxel.org>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-10-18 10:41:43 -04:00
Jeremy Fitzhardinge b21ddbf503 xen: dynamically allocate irq & event structures
Dynamically allocate the irq_info and evtchn_to_irq arrays, so that
1) the irq_info array scales to the actual number of possible irqs,
and 2) we don't needlessly increase the static size of the kernel
when we aren't running under Xen.

Derived on patch from Mike Travis <travis@sgi.com>.

[Impact: reduce memory usage ]
[v2: Conflict in drivers/xen/events.c: Replaced alloc_bootmen with kcalloc ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-10-18 10:41:42 -04:00
Konrad Rzeszutek Wilk 0794bfc743 xen: identity map gsi->irqs
Impact: preserve compat with native

Reserve the lower irq range for use for hardware interrupts so we
can identity-map them.

[v2: Rebased on top tip/irq/core]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-10-18 10:41:08 -04:00
Jeremy Fitzhardinge d46a78b05c xen: implement pirq type event channels
A privileged PV Xen domain can get direct access to hardware.  In
order for this to be useful, it must be able to get hardware
interrupts.

Being a PV Xen domain, all interrupts are delivered as event channels.
PIRQ event channels are bound to a pirq number and an interrupt
vector.  When a IO APIC raises a hardware interrupt on that vector, it
is delivered as an event channel, which we can deliver to the
appropriate device driver(s).

This patch simply implements the infrastructure for dealing with pirq
event channels.

[ Impact: integrate hardware interrupts into Xen's event scheme ]

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2010-10-18 10:40:29 -04:00
Thomas Gleixner 77dff1c755 x86: xen: Sanitise sparse_irq handling
There seems to be more cleanups possible, but that's left to the xen
experts :)

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
2010-10-12 16:53:44 +02:00
Jeremy Fitzhardinge dffe2e1e1a xen: handle events as edge-triggered
Xen events are logically edge triggered, as Xen only calls the event
upcall when an event is newly set, but not continuously as it remains set.
As a result, use handle_edge_irq rather than handle_level_irq.

This has the important side-effect of fixing a long-standing bug of
events getting lost if:
 - an event's interrupt handler is running
 - the event is migrated to a different vcpu
 - the event is re-triggered

The most noticable symptom of these lost events is occasional lockups
of blkfront.

Many thanks to Tom Kopec and Daniel Stodden in tracking this down.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Tom Kopec <tek@acm.org>
Cc: Daniel Stodden <daniel.stodden@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2010-08-24 11:14:12 -07:00
Jeremy Fitzhardinge aaca49642b xen: use percpu interrupts for IPIs and VIRQs
IPIs and VIRQs are inherently per-cpu event types, so treat them as such:
 - use a specific percpu irq_chip implementation, and
 - handle them with handle_percpu_irq

This makes the path for delivering these interrupts more efficient
(no masking/unmasking, no locks), and it avoid problems with attempts
to migrate them.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
2010-08-24 11:13:28 -07:00
Linus Torvalds 1787985782 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  xen: Do not suspend IPI IRQs.
  powerpc: Use IRQF_NO_SUSPEND not IRQF_TIMER for non-timer interrupts
  ixp4xx-beeper: Use IRQF_NO_SUSPEND not IRQF_TIMER for non-timer interrupt
  irq: Add new IRQ flag IRQF_NO_SUSPEND
2010-08-06 13:25:43 -07:00
Stefano Stabellini ca65f9fc0c Introduce CONFIG_XEN_PVHVM compile option
This patch introduce a CONFIG_XEN_PVHVM compile time option to
enable/disable Xen PV on HVM support.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2010-07-29 11:11:33 -07:00
Ian Campbell 4877c73728 xen: Do not suspend IPI IRQs.
In general the semantics of IPIs are that they are are expected to
continue functioning after dpm_suspend_noirq().

Specifically I have seen a deadlock between the callfunc IPI and the
stop machine used by xen's do_suspend() routine. If one CPU has already
called dpm_suspend_noirq() then there is a window where it can be sent
a callfunc IPI before all the other CPUs have entered stop_cpu().

If this happens then the first CPU ends up spinning in stop_cpu()
waiting for the other to rendezvous in state STOPMACHINE_PREPARE while
the other is spinning in csd_lock_wait().

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: xen-devel@lists.xensource.com
LKML-Reference: <1280398595-29708-4-git-send-email-ian.campbell@citrix.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2010-07-29 13:24:58 +02:00
Stefano Stabellini 99ad198c49 xen: Fix find_unbound_irq in presence of ioapic irqs.
Don't break the assumption that the first 16 irqs are ISA irqs;
make sure that the irq is actually free before using it.

Use dynamic_irq_init_keep_chip_data instead of
dynamic_irq_init so that chip_data is not NULL (a NULL chip_data breaks
setup_vector_irq).

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-07-22 16:46:30 -07:00
Stefano Stabellini 183d03cc4f xen: Xen PCI platform device driver.
Add the xen pci platform device driver that is responsible
for initializing the grant table and xenbus in PV on HVM mode.
Few changes to xenbus and grant table are necessary to allow the delayed
initialization in HVM mode.
Grant table needs few additional modifications to work in HVM mode.

The Xen PCI platform device raises an irq every time an event has been
delivered to us. However these interrupts are only delivered to vcpu 0.
The Xen PCI platform interrupt handler calls xen_hvm_evtchn_do_upcall
that is a little wrapper around __xen_evtchn_do_upcall, the traditional
Xen upcall handler, the very same used with traditional PV guests.

When running on HVM the event channel upcall is never called while in
progress because it is a normal Linux irq handler (and we cannot switch
the irq chip wholesale to the Xen PV ones as we are running QEMU and
might have passed in PCI devices), therefore we cannot be sure that
evtchn_upcall_pending is 0 when returning.
For this reason if evtchn_upcall_pending is set by Xen we need to loop
again on the event channels set pending otherwise we might loose some
event channel deliveries.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-07-22 16:46:09 -07:00