Implement a simple Xen APIC module and use it to deliver MSI/MSIX for Xen HVM guests.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
---
hw/xen.h | 1 +
xen-all.c | 5 +++++
xen-stub.c | 4 ++++
3 files changed, 10 insertions(+), 0 deletions(-)
diff --git a/hw/xen.h b/hw/xen.h
index b46879c..e5926b7 100644
--- a/hw/xen.h
+++ b/hw/xen.h
@@ -34,6 +34,7 @@ static inline int xen_enabled(void)
int xen_pci_slot_get_pirq(PCIDevice *pci_dev, int irq_num);
void xen_piix3_set_irq(void *opaque, int irq_num, int level);
void xen_piix_pci_write_config_client(uint32_t address, uint32_t val, int len);
+void xen_hvm_inject_msi(uint64_t addr, uint32_t data);
void xen_cmos_set_s3_resume(void *opaque, int irq, int level);
qemu_irq *xen_interrupt_controller_init(void);
diff --git a/xen-all.c b/xen-all.c
index 3e6de41..abd2b2d 100644
--- a/xen-all.c
+++ b/xen-all.c
@@ -122,6 +122,11 @@ void xen_piix_pci_write_config_client(uint32_t address,
uint32_t val, int len)
}
}
+void xen_hvm_inject_msi(uint64_t addr, uint32_t data)
+{
+ xc_hvm_inject_msi(xen_xc, xen_domid, addr, data);
+}
+
static void xen_suspend_notifier(Notifier *notifier, void *data)
{
xc_set_hvm_param(xen_xc, xen_domid, HVM_PARAM_ACPI_S_STATE, 3);
diff --git a/xen-stub.c b/xen-stub.c
index 9ea02d4..8ff2b79 100644
--- a/xen-stub.c
+++ b/xen-stub.c
@@ -29,6 +29,10 @@ void xen_piix_pci_write_config_client(uint32_t address,
uint32_t val, int len)
{
}
+void xen_hvm_inject_msi(uint64_t addr, uint32_t data)
+{
+}
+
void xen_cmos_set_s3_resume(void *opaque, int irq, int level)
{
}
--
1.7.2.5
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
---
Makefile.target | 2 +-
hw/pc.c | 8 +++++
hw/xen_apic.c | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 99 insertions(+), 1 deletions(-)
create mode 100644 hw/xen_apic.c
diff --git a/Makefile.target b/Makefile.target
index cff15f0..6210bae 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -235,7 +235,7 @@ QEMU_CFLAGS += $(VNC_PNG_CFLAGS)
obj-$(CONFIG_XEN) += xen-all.o xen_machine_pv.o xen_domainbuild.o
xen-mapcache.o
obj-$(CONFIG_NO_XEN) += xen-stub.o
-obj-i386-$(CONFIG_XEN) += xen_platform.o
+obj-i386-$(CONFIG_XEN) += xen_platform.o xen_apic.o
# Inter-VM PCI shared memory
CONFIG_IVSHMEM diff --git a/hw/pc.c b/hw/pc.c
index 83a1b5b..5585cac 100644
--- a/hw/pc.c
+++ b/hw/pc.c
@@ -42,6 +42,7 @@
#include "sysbus.h"
#include "sysemu.h"
#include "kvm.h"
+#include "xen.h"
#include "blockdev.h"
#include "ui/qemu-spice.h"
#include "memory.h"
@@ -891,9 +892,12 @@ static DeviceState *apic_init(void *env, uint8_t apic_id)
if (kvm_irqchip_in_kernel()) {
dev = qdev_create(NULL, "kvm-apic");
+ } else if (xen_enabled()) {
+ dev = qdev_create(NULL, "xen-apic");
} else {
dev = qdev_create(NULL, "apic");
}
+
qdev_prop_set_uint8(dev, "id", apic_id);
qdev_prop_set_ptr(dev, "cpu_env", env);
qdev_init_nofail(dev);
@@ -912,6 +916,10 @@ static DeviceState *apic_init(void *env, uint8_t apic_id)
msi_supported = true;
}
+ if (xen_enabled()) {
+ msi_supported = true;
+ }
+
return dev;
}
diff --git a/hw/xen_apic.c b/hw/xen_apic.c
new file mode 100644
index 0000000..b1060b7
--- /dev/null
+++ b/hw/xen_apic.c
@@ -0,0 +1,90 @@
+/*
+ * Xen basic APIC support
+ *
+ * Copyright (c) 2012 Citrix
+ *
+ * Authors:
+ * Wei Liu <wei.liu2@citrix.com>
+ *
+ * This work is licensed under the terms of the GNU GPL version 2.
+ * See the COPYING file in the top-level directory.
+ */
+#include "hw/apic_internal.h"
+#include "hw/msi.h"
+#include "xen.h"
+
+static uint64_t xen_apic_mem_read(void *opaque, target_phys_addr_t addr,
+ unsigned size)
+{
+ return -1U;
+}
+
+static void xen_apic_mem_write(void *opaque, target_phys_addr_t addr,
+ uint64_t data, unsigned size)
+{
+ if (size != sizeof(uint32_t)) {
+ fprintf(stderr, "Xen: APIC write data size = %d, invalid\n",
size);
+ return;
+ }
+
+ xen_hvm_inject_msi(addr, data);
+}
+
+static const MemoryRegionOps xen_apic_io_ops = {
+ .read = xen_apic_mem_read,
+ .write = xen_apic_mem_write,
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static void xen_apic_init(APICCommonState *s)
+{
+ memory_region_init_io(&s->io_memory, &xen_apic_io_ops, s,
"xen-apic-msi",
+ MSI_SPACE_SIZE);
+}
+
+static void xen_apic_set_base(APICCommonState *s, uint64_t val)
+{
+}
+
+static void xen_apic_set_tpr(APICCommonState *s, uint8_t val)
+{
+}
+
+static uint8_t xen_apic_get_tpr(APICCommonState *s)
+{
+ return 0;
+}
+
+static void xen_apic_vapic_base_update(APICCommonState *s)
+{
+}
+
+static void xen_apic_external_nmi(APICCommonState *s)
+{
+}
+
+static void xen_apic_class_init(ObjectClass *klass, void *data)
+{
+ APICCommonClass *k = APIC_COMMON_CLASS(klass);
+
+ k->init = xen_apic_init;
+ k->set_base = xen_apic_set_base;
+ k->set_tpr = xen_apic_set_tpr;
+ k->get_tpr = xen_apic_get_tpr;
+ k->vapic_base_update = xen_apic_vapic_base_update;
+ k->external_nmi = xen_apic_external_nmi;
+}
+
+static TypeInfo xen_apic_info = {
+ .name = "xen-apic",
+ .parent = TYPE_APIC_COMMON,
+ .instance_size = sizeof(APICCommonState),
+ .class_init = xen_apic_class_init,
+};
+
+static void xen_apic_register_types(void)
+{
+ type_register_static(&xen_apic_info);
+}
+
+type_init(xen_apic_register_types)
--
1.7.2.5
Il 05/04/2012 11:32, Wei Liu ha scritto:> Implement a simple Xen APIC module and use it to deliver MSI/MSIX for > Xen HVM guests.Only skimmed the patch but yeah, this is what I had in mind. Thanks! Paolo
Stefano Stabellini
2012-Apr-05 10:43 UTC
Re: [PATCH 0/0] MSI/MSIX injection for Xen HVM guests
On Thu, 5 Apr 2012, Paolo Bonzini wrote:> Il 05/04/2012 11:32, Wei Liu ha scritto: > > Implement a simple Xen APIC module and use it to deliver MSI/MSIX for > > Xen HVM guests. > > Only skimmed the patch but yeah, this is what I had in mind. Thanks!It looks good to me too. Paolo, can I add your acked-by?
Il 05/04/2012 12:43, Stefano Stabellini ha scritto:>>> > > Implement a simple Xen APIC module and use it to deliver MSI/MSIX for >>> > > Xen HVM guests. >> > >> > Only skimmed the patch but yeah, this is what I had in mind. Thanks! > It looks good to me too. > Paolo, can I add your acked-by?Acked-by, yes. Reviewed-by, no. :) Paolo
Jan Kiszka
2012-Apr-11 16:01 UTC
Re: [PATCH 2/2] Xen: Add xen-apic support and hook it up.
On 2012-04-11 18:02, Stefano Stabellini wrote:> Jan, Anthony, any opinions on this patch? > If it is OK for you, I am going to include it in the next Xen pull request. >Looks good to me. Jan> > On Thu, 5 Apr 2012, Wei Liu (Intern) wrote: >> >> Signed-off-by: Wei Liu <wei.liu2@citrix.com> >> --- >> Makefile.target | 2 +- >> hw/pc.c | 8 +++++ >> hw/xen_apic.c | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ >> 3 files changed, 99 insertions(+), 1 deletions(-) >> create mode 100644 hw/xen_apic.c >> >> diff --git a/Makefile.target b/Makefile.target >> index cff15f0..6210bae 100644 >> --- a/Makefile.target >> +++ b/Makefile.target >> @@ -235,7 +235,7 @@ QEMU_CFLAGS += $(VNC_PNG_CFLAGS) >> obj-$(CONFIG_XEN) += xen-all.o xen_machine_pv.o xen_domainbuild.o xen-mapcache.o >> obj-$(CONFIG_NO_XEN) += xen-stub.o >> >> -obj-i386-$(CONFIG_XEN) += xen_platform.o >> +obj-i386-$(CONFIG_XEN) += xen_platform.o xen_apic.o >> >> # Inter-VM PCI shared memory >> CONFIG_IVSHMEM >> diff --git a/hw/pc.c b/hw/pc.c >> index 83a1b5b..5585cac 100644 >> --- a/hw/pc.c >> +++ b/hw/pc.c >> @@ -42,6 +42,7 @@ >> #include "sysbus.h" >> #include "sysemu.h" >> #include "kvm.h" >> +#include "xen.h" >> #include "blockdev.h" >> #include "ui/qemu-spice.h" >> #include "memory.h" >> @@ -891,9 +892,12 @@ static DeviceState *apic_init(void *env, uint8_t apic_id) >> >> if (kvm_irqchip_in_kernel()) { >> dev = qdev_create(NULL, "kvm-apic"); >> + } else if (xen_enabled()) { >> + dev = qdev_create(NULL, "xen-apic"); >> } else { >> dev = qdev_create(NULL, "apic"); >> } >> + >> qdev_prop_set_uint8(dev, "id", apic_id); >> qdev_prop_set_ptr(dev, "cpu_env", env); >> qdev_init_nofail(dev); >> @@ -912,6 +916,10 @@ static DeviceState *apic_init(void *env, uint8_t apic_id) >> msi_supported = true; >> } >> >> + if (xen_enabled()) { >> + msi_supported = true; >> + } >> + >> return dev; >> } >> >> diff --git a/hw/xen_apic.c b/hw/xen_apic.c >> new file mode 100644 >> index 0000000..b1060b7 >> --- /dev/null >> +++ b/hw/xen_apic.c >> @@ -0,0 +1,90 @@ >> +/* >> + * Xen basic APIC support >> + * >> + * Copyright (c) 2012 Citrix >> + * >> + * Authors: >> + * Wei Liu <wei.liu2@citrix.com> >> + * >> + * This work is licensed under the terms of the GNU GPL version 2. >> + * See the COPYING file in the top-level directory. >> + */ >> +#include "hw/apic_internal.h" >> +#include "hw/msi.h" >> +#include "xen.h" >> + >> +static uint64_t xen_apic_mem_read(void *opaque, target_phys_addr_t addr, >> + unsigned size) >> +{ >> + return -1U; >> +} >> + >> +static void xen_apic_mem_write(void *opaque, target_phys_addr_t addr, >> + uint64_t data, unsigned size) >> +{ >> + if (size != sizeof(uint32_t)) { >> + fprintf(stderr, "Xen: APIC write data size = %d, invalid\n", size); >> + return; >> + } >> + >> + xen_hvm_inject_msi(addr, data); >> +} >> + >> +static const MemoryRegionOps xen_apic_io_ops = { >> + .read = xen_apic_mem_read, >> + .write = xen_apic_mem_write, >> + .endianness = DEVICE_NATIVE_ENDIAN, >> +}; >> + >> +static void xen_apic_init(APICCommonState *s) >> +{ >> + memory_region_init_io(&s->io_memory, &xen_apic_io_ops, s, "xen-apic-msi", >> + MSI_SPACE_SIZE); >> +} >> + >> +static void xen_apic_set_base(APICCommonState *s, uint64_t val) >> +{ >> +} >> + >> +static void xen_apic_set_tpr(APICCommonState *s, uint8_t val) >> +{ >> +} >> + >> +static uint8_t xen_apic_get_tpr(APICCommonState *s) >> +{ >> + return 0; >> +} >> + >> +static void xen_apic_vapic_base_update(APICCommonState *s) >> +{ >> +} >> + >> +static void xen_apic_external_nmi(APICCommonState *s) >> +{ >> +} >> + >> +static void xen_apic_class_init(ObjectClass *klass, void *data) >> +{ >> + APICCommonClass *k = APIC_COMMON_CLASS(klass); >> + >> + k->init = xen_apic_init; >> + k->set_base = xen_apic_set_base; >> + k->set_tpr = xen_apic_set_tpr; >> + k->get_tpr = xen_apic_get_tpr; >> + k->vapic_base_update = xen_apic_vapic_base_update; >> + k->external_nmi = xen_apic_external_nmi; >> +} >> + >> +static TypeInfo xen_apic_info = { >> + .name = "xen-apic", >> + .parent = TYPE_APIC_COMMON, >> + .instance_size = sizeof(APICCommonState), >> + .class_init = xen_apic_class_init, >> +}; >> + >> +static void xen_apic_register_types(void) >> +{ >> + type_register_static(&xen_apic_info); >> +} >> + >> +type_init(xen_apic_register_types) >> -- >> 1.7.2.5 >> >> >> >> >>-- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux
Stefano Stabellini
2012-Apr-11 16:02 UTC
Re: [PATCH 2/2] Xen: Add xen-apic support and hook it up.
Jan, Anthony, any opinions on this patch? If it is OK for you, I am going to include it in the next Xen pull request. On Thu, 5 Apr 2012, Wei Liu (Intern) wrote:> > Signed-off-by: Wei Liu <wei.liu2@citrix.com> > --- > Makefile.target | 2 +- > hw/pc.c | 8 +++++ > hw/xen_apic.c | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 99 insertions(+), 1 deletions(-) > create mode 100644 hw/xen_apic.c > > diff --git a/Makefile.target b/Makefile.target > index cff15f0..6210bae 100644 > --- a/Makefile.target > +++ b/Makefile.target > @@ -235,7 +235,7 @@ QEMU_CFLAGS += $(VNC_PNG_CFLAGS) > obj-$(CONFIG_XEN) += xen-all.o xen_machine_pv.o xen_domainbuild.o xen-mapcache.o > obj-$(CONFIG_NO_XEN) += xen-stub.o > > -obj-i386-$(CONFIG_XEN) += xen_platform.o > +obj-i386-$(CONFIG_XEN) += xen_platform.o xen_apic.o > > # Inter-VM PCI shared memory > CONFIG_IVSHMEM > diff --git a/hw/pc.c b/hw/pc.c > index 83a1b5b..5585cac 100644 > --- a/hw/pc.c > +++ b/hw/pc.c > @@ -42,6 +42,7 @@ > #include "sysbus.h" > #include "sysemu.h" > #include "kvm.h" > +#include "xen.h" > #include "blockdev.h" > #include "ui/qemu-spice.h" > #include "memory.h" > @@ -891,9 +892,12 @@ static DeviceState *apic_init(void *env, uint8_t apic_id) > > if (kvm_irqchip_in_kernel()) { > dev = qdev_create(NULL, "kvm-apic"); > + } else if (xen_enabled()) { > + dev = qdev_create(NULL, "xen-apic"); > } else { > dev = qdev_create(NULL, "apic"); > } > + > qdev_prop_set_uint8(dev, "id", apic_id); > qdev_prop_set_ptr(dev, "cpu_env", env); > qdev_init_nofail(dev); > @@ -912,6 +916,10 @@ static DeviceState *apic_init(void *env, uint8_t apic_id) > msi_supported = true; > } > > + if (xen_enabled()) { > + msi_supported = true; > + } > + > return dev; > } > > diff --git a/hw/xen_apic.c b/hw/xen_apic.c > new file mode 100644 > index 0000000..b1060b7 > --- /dev/null > +++ b/hw/xen_apic.c > @@ -0,0 +1,90 @@ > +/* > + * Xen basic APIC support > + * > + * Copyright (c) 2012 Citrix > + * > + * Authors: > + * Wei Liu <wei.liu2@citrix.com> > + * > + * This work is licensed under the terms of the GNU GPL version 2. > + * See the COPYING file in the top-level directory. > + */ > +#include "hw/apic_internal.h" > +#include "hw/msi.h" > +#include "xen.h" > + > +static uint64_t xen_apic_mem_read(void *opaque, target_phys_addr_t addr, > + unsigned size) > +{ > + return -1U; > +} > + > +static void xen_apic_mem_write(void *opaque, target_phys_addr_t addr, > + uint64_t data, unsigned size) > +{ > + if (size != sizeof(uint32_t)) { > + fprintf(stderr, "Xen: APIC write data size = %d, invalid\n", size); > + return; > + } > + > + xen_hvm_inject_msi(addr, data); > +} > + > +static const MemoryRegionOps xen_apic_io_ops = { > + .read = xen_apic_mem_read, > + .write = xen_apic_mem_write, > + .endianness = DEVICE_NATIVE_ENDIAN, > +}; > + > +static void xen_apic_init(APICCommonState *s) > +{ > + memory_region_init_io(&s->io_memory, &xen_apic_io_ops, s, "xen-apic-msi", > + MSI_SPACE_SIZE); > +} > + > +static void xen_apic_set_base(APICCommonState *s, uint64_t val) > +{ > +} > + > +static void xen_apic_set_tpr(APICCommonState *s, uint8_t val) > +{ > +} > + > +static uint8_t xen_apic_get_tpr(APICCommonState *s) > +{ > + return 0; > +} > + > +static void xen_apic_vapic_base_update(APICCommonState *s) > +{ > +} > + > +static void xen_apic_external_nmi(APICCommonState *s) > +{ > +} > + > +static void xen_apic_class_init(ObjectClass *klass, void *data) > +{ > + APICCommonClass *k = APIC_COMMON_CLASS(klass); > + > + k->init = xen_apic_init; > + k->set_base = xen_apic_set_base; > + k->set_tpr = xen_apic_set_tpr; > + k->get_tpr = xen_apic_get_tpr; > + k->vapic_base_update = xen_apic_vapic_base_update; > + k->external_nmi = xen_apic_external_nmi; > +} > + > +static TypeInfo xen_apic_info = { > + .name = "xen-apic", > + .parent = TYPE_APIC_COMMON, > + .instance_size = sizeof(APICCommonState), > + .class_init = xen_apic_class_init, > +}; > + > +static void xen_apic_register_types(void) > +{ > + type_register_static(&xen_apic_info); > +} > + > +type_init(xen_apic_register_types) > -- > 1.7.2.5 > > > > >
Peter Maydell
2012-Apr-11 16:07 UTC
Re: [PATCH 2/2] Xen: Add xen-apic support and hook it up.
On 5 April 2012 10:35, Wei Liu <wei.liu2@citrix.com> wrote:> > --- /dev/null > +++ b/hw/xen_apic.c > @@ -0,0 +1,90 @@ > +/* > + * Xen basic APIC support > + * > + * Copyright (c) 2012 Citrix > + * > + * Authors: > + * Wei Liu <wei.liu2@citrix.com> > + * > + * This work is licensed under the terms of the GNU GPL version 2. > + * See the COPYING file in the top-level directory. > + */Really 2-only, not 2-or-later ?> +#include "hw/apic_internal.h" > +#include "hw/msi.h" > +#include "xen.h" > + > +static uint64_t xen_apic_mem_read(void *opaque, target_phys_addr_t addr, > + unsigned size) > +{ > + return -1U; > +}This seems a rather confusing way to write ''return 0xffffffff;'' -- PMM
Jan Kiszka
2012-Apr-11 16:13 UTC
Re: [PATCH 2/2] Xen: Add xen-apic support and hook it up.
On 2012-04-11 18:07, Peter Maydell wrote:>> +#include "hw/apic_internal.h" >> +#include "hw/msi.h" >> +#include "xen.h" >> + >> +static uint64_t xen_apic_mem_read(void *opaque, target_phys_addr_t addr, >> + unsigned size) >> +{ >> + return -1U; >> +} > > This seems a rather confusing way to write ''return 0xffffffff;''You mean 0xffffffffffffffff? :) Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux
Stefano Stabellini
2012-Apr-11 16:17 UTC
Re: [PATCH 2/2] Xen: Add xen-apic support and hook it up.
On Wed, 11 Apr 2012, Peter Maydell wrote:> On 5 April 2012 10:35, Wei Liu <wei.liu2@citrix.com> wrote: > > > > --- /dev/null > > +++ b/hw/xen_apic.c > > @@ -0,0 +1,90 @@ > > +/* > > + * Xen basic APIC support > > + * > > + * Copyright (c) 2012 Citrix > > + * > > + * Authors: > > + * Wei Liu <wei.liu2@citrix.com> > > + * > > + * This work is licensed under the terms of the GNU GPL version 2. > > + * See the COPYING file in the top-level directory. > > + */ > > Really 2-only, not 2-or-later ?I am not a great fun of the 2-or-later clause and it doesn''t look like a requirement from the QEMU project POV. However if it is, I''ll change it to 2-or-later.> > +#include "hw/apic_internal.h" > > +#include "hw/msi.h" > > +#include "xen.h" > > + > > +static uint64_t xen_apic_mem_read(void *opaque, target_phys_addr_t addr, > > + unsigned size) > > +{ > > + return -1U; > > +} > > This seems a rather confusing way to write ''return 0xffffffff;''Yep, I''ll change it. --8323329-1457749389-1334161050=:15151--
Stefano Stabellini
2012-Apr-11 16:19 UTC
Re: [PATCH 2/2] Xen: Add xen-apic support and hook it up.
On Wed, 11 Apr 2012, Stefano Stabellini wrote:> On Wed, 11 Apr 2012, Peter Maydell wrote: > > On 5 April 2012 10:35, Wei Liu <wei.liu2@citrix.com> wrote: > > > > > > --- /dev/null > > > +++ b/hw/xen_apic.c > > > @@ -0,0 +1,90 @@ > > > +/* > > > + * Xen basic APIC support > > > + * > > > + * Copyright (c) 2012 Citrix > > > + * > > > + * Authors: > > > + * Wei Liu <wei.liu2@citrix.com> > > > + * > > > + * This work is licensed under the terms of the GNU GPL version 2. > > > + * See the COPYING file in the top-level directory. > > > + */ > > > > Really 2-only, not 2-or-later ? > > I am not a great fun of the 2-or-later clause and it doesn''t look like a > requirement from the QEMU project POV. However if it is, I''ll change it > to 2-or-later. > > > > > +#include "hw/apic_internal.h" > > > +#include "hw/msi.h" > > > +#include "xen.h" > > > + > > > +static uint64_t xen_apic_mem_read(void *opaque, target_phys_addr_t addr, > > > + unsigned size) > > > +{ > > > + return -1U; > > > +} > > > > This seems a rather confusing way to write ''return 0xffffffff;'' > > Yep, I''ll change it.Actually it is a uint64 so it is a lot of f''s --8323329-1771022453-1334161164=:15151--
Peter Maydell
2012-Apr-11 16:23 UTC
Re: [PATCH 2/2] Xen: Add xen-apic support and hook it up.
On 11 April 2012 17:13, Jan Kiszka <jan.kiszka@siemens.com> wrote:> On 2012-04-11 18:07, Peter Maydell wrote: >>> +#include "hw/apic_internal.h" >>> +#include "hw/msi.h" >>> +#include "xen.h" >>> + >>> +static uint64_t xen_apic_mem_read(void *opaque, target_phys_addr_t addr, >>> + unsigned size) >>> +{ >>> + return -1U; >>> +} >> >> This seems a rather confusing way to write ''return 0xffffffff;'' > > You mean 0xffffffffffffffff? :)No, that''s why it''s confusing :-) 1U is the integer constant 1 with a type of ''unsigned int'' (cf C99 section 6.4.4.1). It then has the unary negation operator applied to it, giving (for the usual 32 bit integer case) 0xffffffff. This is then cast from ''unsigned int'' to ''uint64_t'' giving 0xffffffff as a 64 bit unsigned value. (I had to write a test program to (a) confirm what it was going to return and (b) that it would be the same thing on both 32 and 64 bit systems...) I have no opinion on what the return value actually ought to be. -- PMM
Eric Blake
2012-Apr-11 17:02 UTC
Re: [PATCH 2/2] Xen: Add xen-apic support and hook it up.
On 04/11/2012 10:17 AM, Stefano Stabellini wrote:> On Wed, 11 Apr 2012, Peter Maydell wrote: >> On 5 April 2012 10:35, Wei Liu <wei.liu2@citrix.com> wrote: >>> >>> --- /dev/null >>> +++ b/hw/xen_apic.c >>> @@ -0,0 +1,90 @@ >>> +/* >>> + * Xen basic APIC support >>> + * >>> + * Copyright (c) 2012 Citrix >>> + * >>> + * Authors: >>> + * Wei Liu <wei.liu2@citrix.com> >>> + * >>> + * This work is licensed under the terms of the GNU GPL version 2. >>> + * See the COPYING file in the top-level directory. >>> + */ >> >> Really 2-only, not 2-or-later ? > > I am not a great fun of the 2-or-later clause and it doesn''t look like a > requirement from the QEMU project POV. However if it is, I''ll change it > to 2-or-later.Conversely, I am not a great fan of the 2-only clause, as it prevents reuse of qemu code in other projects. There''s a reason that qemu is now favoring 2-or-later for new submissions. http://wiki.qemu.org/Relicensing -- Eric Blake eblake@redhat.com +1-919-301-3266 Libvirt virtualization library http://libvirt.org
Paolo Bonzini
2012-Apr-11 21:37 UTC
Re: [PATCH 2/2] Xen: Add xen-apic support and hook it up.
Il 11/04/2012 18:17, Stefano Stabellini ha scritto:>> > Really 2-only, not 2-or-later ? > I am not a great fun of the 2-or-later clause and it doesn''t look like a > requirement from the QEMU project POV. However if it is, I''ll change it > to 2-or-later.OT fun fact: did you know that MPL comes with an or-later clause that (unlike the GPL) you cannot reject? So much for "weak" copyleft. Paolo
Wei Liu
2012-Apr-12 03:23 UTC
Re: [Qemu-devel] [PATCH 2/2] Xen: Add xen-apic support and hook it up.
On Thu, Apr 12, 2012 at 1:02 AM, Eric Blake <eblake@redhat.com> wrote:> On 04/11/2012 10:17 AM, Stefano Stabellini wrote: >> On Wed, 11 Apr 2012, Peter Maydell wrote: >>> On 5 April 2012 10:35, Wei Liu <wei.liu2@citrix.com> wrote: >>>> >>>> --- /dev/null >>>> +++ b/hw/xen_apic.c >>>> @@ -0,0 +1,90 @@ >>>> +/* >>>> + * Xen basic APIC support >>>> + * >>>> + * Copyright (c) 2012 Citrix >>>> + * >>>> + * Authors: >>>> + * Wei Liu <wei.liu2@citrix.com> >>>> + * >>>> + * This work is licensed under the terms of the GNU GPL version 2. >>>> + * See the COPYING file in the top-level directory. >>>> + */ >>> >>> Really 2-only, not 2-or-later ? >> >> I am not a great fun of the 2-or-later clause and it doesn't look like a >> requirement from the QEMU project POV. However if it is, I'll change it >> to 2-or-later. > > Conversely, I am not a great fan of the 2-only clause, as it prevents > reuse of qemu code in other projects. There's a reason that qemu is now > favoring 2-or-later for new submissions. > > http://wiki.qemu.org/Relicensing >I don't mind changing the licensing to 2-or-later for greater benefit. Stefano, please do whatever you need to. Wei.> -- > Eric Blake eblake@redhat.com +1-919-301-3266 > Libvirt virtualization library http://libvirt.org >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel