linux/drivers
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
..
accessibility
acpi ACPI / PM: Call suspend_nvs_free() earlier during resume 2011-01-20 18:30:17 -08:00
amba
ata libata: set queue DMA alignment to sector size for ATAPI too 2011-01-28 03:16:20 -05:00
atm Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 2011-01-24 13:17:06 -08:00
auxdisplay
base PM / Runtime: Don't enable interrupts while running in_interrupt 2011-01-25 20:50:07 +01:00
block Merge branch 'for-2.6.38/drivers' of git://git.kernel.dk/linux-2.6-block 2011-01-13 10:50:24 -08:00
bluetooth Bluetooth: ath3k: reduce memory usage 2011-01-19 14:40:41 -02:00
cdrom Merge branch 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block 2011-01-13 10:45:01 -08:00
char agp: ensure GART has an address before enabling it 2011-02-04 09:43:57 +10:00
clk
clocksource drivers/clocksource/tcb_clksrc.c: fix init sequence 2011-01-26 10:50:04 +10:00
connector
cpufreq kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT 2011-01-20 17:02:05 -08:00
cpuidle Merge branch 'cpuidle-perf-events' into idle-test 2011-01-12 18:06:19 -05:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2011-01-13 10:25:58 -08:00
dca dca: remove unneeded NULL check 2011-01-13 08:03:09 -08:00
dio
dma Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx 2011-01-17 10:54:41 -08:00
edac Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-01-13 10:05:56 -08:00
eisa
firewire Merge branches 'fixes' and 'fwnet' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6 2011-01-21 13:34:39 -08:00
firmware kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT 2011-01-20 17:02:05 -08:00
gpio langwell_gpio: modify EOI handling following change of kernel irq subsystem 2011-01-26 10:49:59 +10:00
gpu Merge branch 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 2011-02-04 10:02:22 -08:00
hid kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT 2011-01-20 17:02:05 -08:00
hwmon hwmon: (lis3) turn down the no IRQ message 2011-01-25 09:10:50 -08:00
i2c i2c: Encourage move to dev_pm_ops by warning on use of legacy methods 2011-01-14 22:03:50 +01:00
ide kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT 2011-01-20 17:02:05 -08:00
idle fix a shutdown regression in intel_idle 2011-01-25 05:57:34 +10:00
ieee802154
infiniband Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband 2011-02-03 11:19:26 -08:00
input arm/ixp4xx: Rename FREQ macro to avoid collisions 2011-02-06 16:49:48 +01:00
isdn isdn: icn: Fix potentially wrong string handling 2011-02-01 14:17:51 -08:00
leds leds: leds-pwm: return proper error if pwm_request failed 2011-01-26 10:49:58 +10:00
lguest lguest: compile fixes 2011-01-20 21:37:29 +10:30
macintosh powerpc/macintosh: Fix wrong test in fan_{read,write}_reg() 2011-01-21 14:08:34 +11:00
mca
md block: restore multiple bd_link_disk_holder() support 2011-01-14 18:44:22 +01:00
media Merge branch 'media_fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6 2011-02-02 17:52:19 -08:00
memstick memstick: factor out transfer initiating functionality in mspro_block.c 2011-01-13 08:03:22 -08:00
message
mfd mfd: ab8500-core chip version cut 2.0 support 2011-01-14 12:38:18 +01:00
misc misc: Make AB8500_PWM driver depend on U8500 due to PWM breakage 2011-01-14 12:38:12 +01:00
mmc ARM: mmci: round down the bytes transferred on error 2011-01-31 10:53:37 +00:00
mtd Revert "UBI: use mtd->writebufsize to set minimal I/O unit size" 2011-01-29 18:27:13 +02:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2011-02-04 13:20:01 -08:00
nfc drivers/nfc/pn544.c: fix min_t warnings 2011-01-16 17:28:21 -08:00
nubus
of dt/flattree: Return virtual address from early_init_dt_alloc_memory_arch() 2011-01-15 22:01:58 -07:00
oprofile
parisc
parport parport: make lockdep happy with waitlist_lock 2011-01-26 10:49:59 +10:00
pci kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT 2011-01-20 17:02:05 -08:00
pcmcia kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT 2011-01-20 17:02:05 -08:00
platform intel_scu_ipc: remove duplicated #include 2011-01-31 12:59:34 +10:00
pnp
power Merge git://git.infradead.org/battery-2.6 2011-01-14 09:25:59 -08:00
pps pps: claim parallel port exclusively 2011-01-26 10:50:00 +10:00
ps3
rapidio rapidio: fix new kernel-doc warnings 2011-01-22 20:32:37 -08:00
regulator regulator: Support MAX8998/LP3974 DVS-GPIO 2011-01-14 12:38:16 +01:00
rtc RTC: Prevents a division by zero in kernel code. 2011-02-03 12:59:50 -08:00
s390 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2011-02-04 13:20:01 -08:00
sbus
scsi [SCSI] libsas: fix runaway error handler problem 2011-01-24 11:52:33 -06:00
sfi
sh sh: update INTC to clear IRQ sense valid flag 2011-01-19 19:02:35 +09:00
sn
spi Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/upstream-linus 2011-01-18 14:28:48 -08:00
ssb kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT 2011-01-20 17:02:05 -08:00
staging Merge branch 'media_fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6 2011-02-02 17:52:19 -08:00
target [SCSI] target: Add LIO target core v4.0.0-rc6 2011-01-14 10:12:29 -06:00
tc
telephony Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-01-13 10:05:56 -08:00
thermal
tty Merge branch 'tty-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6 2011-02-01 08:05:19 +10:00
uio
usb Merge branch 'for-usb-linus' of master.kernel.org:/pub/scm/linux/kernel/git/sarah/xhci into usb-linus 2011-01-24 08:14:07 +09:00
uwb
vhost vhost: rcu annotation fixup 2011-02-01 16:48:46 +02:00
video console: rename acquire/release_console_sem() to console_lock/unlock() 2011-01-26 10:50:06 +10:00
virtio virtio: remove virtio-pci root device 2011-01-20 21:37:30 +10:30
vlynq
w1 w1: DS2423 counter driver and documentation 2011-01-13 08:03:22 -08:00
watchdog watchdog: Add MCF548x watchdog driver. 2011-01-12 13:51:35 +00:00
xen xen: events: allocate GSIs and dynamic IRQs from separate IRQ ranges. 2011-03-03 12:00:21 -05:00
zorro
Kconfig [SCSI] target: Add LIO target core v4.0.0-rc6 2011-01-14 10:12:29 -06:00
Makefile Merge branch 'tty-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6 2011-01-20 16:39:23 -08:00