| Message ID | 1491903346-16075-1-git-send-email-andr2000@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
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On Tue, 11 Apr 2017, Oleksandr Andrushchenko wrote: > From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> > > For some use cases when Xen framebuffer/input backend > is not a part of Qemu it is required to disable it, > because of conflicting access to input/display devices. > Introduce additional configuration option for explicit > input/display control. In these cases when you don't want xenfb, why don't you just remove "vfb" from the xl config file? QEMU only starts the xenfb backend when requested by the toolstack. Is it because you have an alternative xenfb backend? If so, is it really fully xenfb compatible, or is it a different protocol? If it is a different protocol, I suggest you rename your frontend/backend PV device name to something different from "vfb". > Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> > --- > configure | 18 ++++++++++++++++++ > hw/display/Makefile.objs | 2 +- > hw/xen/xen_backend.c | 2 ++ > hw/xenpv/xen_machine_pv.c | 4 ++++ > 4 files changed, 25 insertions(+), 1 deletion(-) > > diff --git a/configure b/configure > index 476210b1b93f..b805cb908f03 100755 > --- a/configure > +++ b/configure > @@ -220,6 +220,7 @@ xen="" > xen_ctrl_version="" > xen_pv_domain_build="no" > xen_pci_passthrough="" > +xen_fb_backend="" > linux_aio="" > cap_ng="" > attr="" > @@ -909,6 +910,10 @@ for opt do > ;; > --enable-xen-pv-domain-build) xen_pv_domain_build="yes" > ;; > + --disable-xen-fb-backend) xen_fb_backend="no" > + ;; > + --enable-xen-fb-backend) xen_fb_backend="yes" > + ;; > --disable-brlapi) brlapi="no" > ;; > --enable-brlapi) brlapi="yes" > @@ -1368,6 +1373,7 @@ disabled with --disable-FEATURE, default is enabled if available: > virtfs VirtFS > xen xen backend driver support > xen-pci-passthrough > + xen-fb-backend framebuffer/input backend support > brlapi BrlAPI (Braile) > curl curl connectivity > fdt fdt device tree > @@ -2213,6 +2219,15 @@ if test "$xen_pv_domain_build" = "yes" && > "which requires Xen support." > fi > > +if test "$xen_fb_backend" != "no"; then > + if test "$xen" = "yes"; then > + xen_fb_backend=yes > + else > + error_exit "User requested feature Xen framebufer backend support" \ > + " but this feature requires Xen support." > + fi > +fi > + > ########################################## > # Sparse probe > if test "$sparse" != "no" ; then > @@ -5444,6 +5459,9 @@ if test "$xen" = "yes" ; then > if test "$xen_pv_domain_build" = "yes" ; then > echo "CONFIG_XEN_PV_DOMAIN_BUILD=y" >> $config_host_mak > fi > + if test "$xen_fb_backend" = "yes" ; then > + echo "CONFIG_XEN_FB_BACKEND=y" >> $config_host_mak > + fi > fi > if test "$linux_aio" = "yes" ; then > echo "CONFIG_LINUX_AIO=y" >> $config_host_mak > diff --git a/hw/display/Makefile.objs b/hw/display/Makefile.objs > index 063889beaf4a..f5ec97ed4f48 100644 > --- a/hw/display/Makefile.objs > +++ b/hw/display/Makefile.objs > @@ -5,7 +5,7 @@ common-obj-$(CONFIG_JAZZ_LED) += jazz_led.o > common-obj-$(CONFIG_PL110) += pl110.o > common-obj-$(CONFIG_SSD0303) += ssd0303.o > common-obj-$(CONFIG_SSD0323) += ssd0323.o > -common-obj-$(CONFIG_XEN_BACKEND) += xenfb.o > +common-obj-$(CONFIG_XEN_FB_BACKEND) += xenfb.o > > common-obj-$(CONFIG_VGA_PCI) += vga-pci.o > common-obj-$(CONFIG_VGA_ISA) += vga-isa.o > diff --git a/hw/xen/xen_backend.c b/hw/xen/xen_backend.c > index d1190041ae12..5146cbba6ca5 100644 > --- a/hw/xen/xen_backend.c > +++ b/hw/xen/xen_backend.c > @@ -582,7 +582,9 @@ void xen_be_register_common(void) > xen_set_dynamic_sysbus(); > > xen_be_register("console", &xen_console_ops); > +#ifdef CONFIG_XEN_FB_BACKEND > xen_be_register("vkbd", &xen_kbdmouse_ops); > +#endif > xen_be_register("qdisk", &xen_blkdev_ops); > #ifdef CONFIG_USB_LIBUSB > xen_be_register("qusb", &xen_usb_ops); > diff --git a/hw/xenpv/xen_machine_pv.c b/hw/xenpv/xen_machine_pv.c > index 79aef4ecc37b..b731344c3f0a 100644 > --- a/hw/xenpv/xen_machine_pv.c > +++ b/hw/xenpv/xen_machine_pv.c > @@ -68,7 +68,9 @@ static void xen_init_pv(MachineState *machine) > } > > xen_be_register_common(); > +#ifdef CONFIG_XEN_FB_BACKEND > xen_be_register("vfb", &xen_framebuffer_ops); > +#endif > xen_be_register("qnic", &xen_netdev_ops); > > /* configure framebuffer */ > @@ -95,8 +97,10 @@ static void xen_init_pv(MachineState *machine) > /* config cleanup hook */ > atexit(xen_config_cleanup); > > +#ifdef CONFIG_XEN_FB_BACKEND > /* setup framebuffer */ > xen_init_display(xen_domid); > +#endif > } > > static void xenpv_machine_init(MachineClass *mc) > -- > 2.7.4 >
On 04/14/2017 03:12 AM, Stefano Stabellini wrote: > On Tue, 11 Apr 2017, Oleksandr Andrushchenko wrote: >> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> >> >> For some use cases when Xen framebuffer/input backend >> is not a part of Qemu it is required to disable it, >> because of conflicting access to input/display devices. >> Introduce additional configuration option for explicit >> input/display control. > In these cases when you don't want xenfb, why don't you just remove > "vfb" from the xl config file? QEMU only starts the xenfb backend when > requested by the toolstack. > > Is it because you have an alternative xenfb backend? If so, is it really > fully xenfb compatible, or is it a different protocol? If it is a > different protocol, I suggest you rename your frontend/backend PV device > name to something different from "vfb". > Well, offending part is vkbd actually (for multi-touch we run our own user-space backend which supports kbd/ptr/mtouch), but vfb and vkbd is the same backend in QEMU. So, I am ok for vfb, but just want vkbd off So, there are 2 options: 1. At compile time remove vkbd and still allow vfb 2. Remove xenfb completely, if acceptable (this is my case) >> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> >> --- >> configure | 18 ++++++++++++++++++ >> hw/display/Makefile.objs | 2 +- >> hw/xen/xen_backend.c | 2 ++ >> hw/xenpv/xen_machine_pv.c | 4 ++++ >> 4 files changed, 25 insertions(+), 1 deletion(-) >> >> diff --git a/configure b/configure >> index 476210b1b93f..b805cb908f03 100755 >> --- a/configure >> +++ b/configure >> @@ -220,6 +220,7 @@ xen="" >> xen_ctrl_version="" >> xen_pv_domain_build="no" >> xen_pci_passthrough="" >> +xen_fb_backend="" >> linux_aio="" >> cap_ng="" >> attr="" >> @@ -909,6 +910,10 @@ for opt do >> ;; >> --enable-xen-pv-domain-build) xen_pv_domain_build="yes" >> ;; >> + --disable-xen-fb-backend) xen_fb_backend="no" >> + ;; >> + --enable-xen-fb-backend) xen_fb_backend="yes" >> + ;; >> --disable-brlapi) brlapi="no" >> ;; >> --enable-brlapi) brlapi="yes" >> @@ -1368,6 +1373,7 @@ disabled with --disable-FEATURE, default is enabled if available: >> virtfs VirtFS >> xen xen backend driver support >> xen-pci-passthrough >> + xen-fb-backend framebuffer/input backend support >> brlapi BrlAPI (Braile) >> curl curl connectivity >> fdt fdt device tree >> @@ -2213,6 +2219,15 @@ if test "$xen_pv_domain_build" = "yes" && >> "which requires Xen support." >> fi >> >> +if test "$xen_fb_backend" != "no"; then >> + if test "$xen" = "yes"; then >> + xen_fb_backend=yes >> + else >> + error_exit "User requested feature Xen framebufer backend support" \ >> + " but this feature requires Xen support." >> + fi >> +fi >> + >> ########################################## >> # Sparse probe >> if test "$sparse" != "no" ; then >> @@ -5444,6 +5459,9 @@ if test "$xen" = "yes" ; then >> if test "$xen_pv_domain_build" = "yes" ; then >> echo "CONFIG_XEN_PV_DOMAIN_BUILD=y" >> $config_host_mak >> fi >> + if test "$xen_fb_backend" = "yes" ; then >> + echo "CONFIG_XEN_FB_BACKEND=y" >> $config_host_mak >> + fi >> fi >> if test "$linux_aio" = "yes" ; then >> echo "CONFIG_LINUX_AIO=y" >> $config_host_mak >> diff --git a/hw/display/Makefile.objs b/hw/display/Makefile.objs >> index 063889beaf4a..f5ec97ed4f48 100644 >> --- a/hw/display/Makefile.objs >> +++ b/hw/display/Makefile.objs >> @@ -5,7 +5,7 @@ common-obj-$(CONFIG_JAZZ_LED) += jazz_led.o >> common-obj-$(CONFIG_PL110) += pl110.o >> common-obj-$(CONFIG_SSD0303) += ssd0303.o >> common-obj-$(CONFIG_SSD0323) += ssd0323.o >> -common-obj-$(CONFIG_XEN_BACKEND) += xenfb.o >> +common-obj-$(CONFIG_XEN_FB_BACKEND) += xenfb.o >> >> common-obj-$(CONFIG_VGA_PCI) += vga-pci.o >> common-obj-$(CONFIG_VGA_ISA) += vga-isa.o >> diff --git a/hw/xen/xen_backend.c b/hw/xen/xen_backend.c >> index d1190041ae12..5146cbba6ca5 100644 >> --- a/hw/xen/xen_backend.c >> +++ b/hw/xen/xen_backend.c >> @@ -582,7 +582,9 @@ void xen_be_register_common(void) >> xen_set_dynamic_sysbus(); >> >> xen_be_register("console", &xen_console_ops); >> +#ifdef CONFIG_XEN_FB_BACKEND >> xen_be_register("vkbd", &xen_kbdmouse_ops); >> +#endif >> xen_be_register("qdisk", &xen_blkdev_ops); >> #ifdef CONFIG_USB_LIBUSB >> xen_be_register("qusb", &xen_usb_ops); >> diff --git a/hw/xenpv/xen_machine_pv.c b/hw/xenpv/xen_machine_pv.c >> index 79aef4ecc37b..b731344c3f0a 100644 >> --- a/hw/xenpv/xen_machine_pv.c >> +++ b/hw/xenpv/xen_machine_pv.c >> @@ -68,7 +68,9 @@ static void xen_init_pv(MachineState *machine) >> } >> >> xen_be_register_common(); >> +#ifdef CONFIG_XEN_FB_BACKEND >> xen_be_register("vfb", &xen_framebuffer_ops); >> +#endif >> xen_be_register("qnic", &xen_netdev_ops); >> >> /* configure framebuffer */ >> @@ -95,8 +97,10 @@ static void xen_init_pv(MachineState *machine) >> /* config cleanup hook */ >> atexit(xen_config_cleanup); >> >> +#ifdef CONFIG_XEN_FB_BACKEND >> /* setup framebuffer */ >> xen_init_display(xen_domid); >> +#endif >> } >> >> static void xenpv_machine_init(MachineClass *mc) >> -- >> 2.7.4 >>
On 14/04/17 08:06, Oleksandr Andrushchenko wrote: > On 04/14/2017 03:12 AM, Stefano Stabellini wrote: >> On Tue, 11 Apr 2017, Oleksandr Andrushchenko wrote: >>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> >>> >>> For some use cases when Xen framebuffer/input backend >>> is not a part of Qemu it is required to disable it, >>> because of conflicting access to input/display devices. >>> Introduce additional configuration option for explicit >>> input/display control. >> In these cases when you don't want xenfb, why don't you just remove >> "vfb" from the xl config file? QEMU only starts the xenfb backend when >> requested by the toolstack. >> >> Is it because you have an alternative xenfb backend? If so, is it really >> fully xenfb compatible, or is it a different protocol? If it is a >> different protocol, I suggest you rename your frontend/backend PV device >> name to something different from "vfb". >> > Well, offending part is vkbd actually (for multi-touch > we run our own user-space backend which supports > kbd/ptr/mtouch), but vfb and vkbd is the same backend > in QEMU. So, I am ok for vfb, but just want vkbd off > So, there are 2 options: > 1. At compile time remove vkbd and still allow vfb > 2. Remove xenfb completely, if acceptable (this is my case) What about adding a Xenstore entry for backend type and let qemu test for it being not present or containing "qemu"? Juergen
On Fri, 14 Apr 2017, Juergen Gross wrote: > On 14/04/17 08:06, Oleksandr Andrushchenko wrote: > > On 04/14/2017 03:12 AM, Stefano Stabellini wrote: > >> On Tue, 11 Apr 2017, Oleksandr Andrushchenko wrote: > >>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> > >>> > >>> For some use cases when Xen framebuffer/input backend > >>> is not a part of Qemu it is required to disable it, > >>> because of conflicting access to input/display devices. > >>> Introduce additional configuration option for explicit > >>> input/display control. > >> In these cases when you don't want xenfb, why don't you just remove > >> "vfb" from the xl config file? QEMU only starts the xenfb backend when > >> requested by the toolstack. > >> > >> Is it because you have an alternative xenfb backend? If so, is it really > >> fully xenfb compatible, or is it a different protocol? If it is a > >> different protocol, I suggest you rename your frontend/backend PV device > >> name to something different from "vfb". > >> > > Well, offending part is vkbd actually (for multi-touch > > we run our own user-space backend which supports > > kbd/ptr/mtouch), but vfb and vkbd is the same backend > > in QEMU. So, I am ok for vfb, but just want vkbd off > > So, there are 2 options: > > 1. At compile time remove vkbd and still allow vfb > > 2. Remove xenfb completely, if acceptable (this is my case) > > What about adding a Xenstore entry for backend type and let qemu test > for it being not present or containing "qemu"? That is what we do for the console, using the xenstore node "type". QEMU is "ioemu" while xenconsoled is "xenconsoled". Weirdly, instead of a backend node, it is a read-only frontend node, see tools/libxl/libxl_console.c:libxl__device_console_add. Oleksandr, I am sorry to feature-creep this simple patch, but I think Juergen is right. But we cannot do it just for one protocol. We need to introduce a generic way to enable/disable backends in QEMU. Using a xenstore node is OK. We could do exactly the same as the PV console, thus "type" = "ioemu", read-only, under the frontend xenstore directory. Or we could introduce new nodes. I would probably go for "backend-type" = "qemu" under the backend xenstore directory. I don't have a strong opinion about this. In the example below I'll use the PV console convention. For starters: * libxl needs to write the "type" node to xenstore for *all* protocols. The "type" is not yet configurable. * qemu reads them for all backends, proceeds if "type" = "ioemu" These should be two simple patches. Stage 2: * we add options in the xl config file to configure any backend, libxl set "type" accordingly (Maybe not *any*, but vif, vkbd, vfb could all have a "type". It is OK if you only add an option for vkbd.) * non-QEMU backends, in particular Linux backends, also read the "type" node and proceed if it's "linux" Does this sound OK to you?
On 14/04/17 19:52, Stefano Stabellini wrote: > On Fri, 14 Apr 2017, Juergen Gross wrote: >> On 14/04/17 08:06, Oleksandr Andrushchenko wrote: >>> On 04/14/2017 03:12 AM, Stefano Stabellini wrote: >>>> On Tue, 11 Apr 2017, Oleksandr Andrushchenko wrote: >>>>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> >>>>> >>>>> For some use cases when Xen framebuffer/input backend >>>>> is not a part of Qemu it is required to disable it, >>>>> because of conflicting access to input/display devices. >>>>> Introduce additional configuration option for explicit >>>>> input/display control. >>>> In these cases when you don't want xenfb, why don't you just remove >>>> "vfb" from the xl config file? QEMU only starts the xenfb backend when >>>> requested by the toolstack. >>>> >>>> Is it because you have an alternative xenfb backend? If so, is it really >>>> fully xenfb compatible, or is it a different protocol? If it is a >>>> different protocol, I suggest you rename your frontend/backend PV device >>>> name to something different from "vfb". >>>> >>> Well, offending part is vkbd actually (for multi-touch >>> we run our own user-space backend which supports >>> kbd/ptr/mtouch), but vfb and vkbd is the same backend >>> in QEMU. So, I am ok for vfb, but just want vkbd off >>> So, there are 2 options: >>> 1. At compile time remove vkbd and still allow vfb >>> 2. Remove xenfb completely, if acceptable (this is my case) >> >> What about adding a Xenstore entry for backend type and let qemu test >> for it being not present or containing "qemu"? > > That is what we do for the console, using the xenstore node "type". QEMU > is "ioemu" while xenconsoled is "xenconsoled". Weirdly, instead of a > backend node, it is a read-only frontend node, see > tools/libxl/libxl_console.c:libxl__device_console_add. > > Oleksandr, I am sorry to feature-creep this simple patch, but I think > Juergen is right. But we cannot do it just for one protocol. We need to > introduce a generic way to enable/disable backends in QEMU. Using a > xenstore node is OK. An alternative solution would be similar to qdisk/tap or qusb/vusb backends: Use different device types on backend side while keeping frontend side of Xenstore the same as today. So today the vkbd backend nodes are: /local/domain/0/backend/vkbd/ You could use: /local/domain/0/backend/mtouch and keep the frontend nodes (/local/domain/<n>/device/vkbd/), possibly with additional feature node(s). The qemu backend would have to check for the vkbd backend nodes to be present before enabling the related backend. Juergen > > We could do exactly the same as the PV console, thus "type" = "ioemu", > read-only, under the frontend xenstore directory. Or we could introduce > new nodes. I would probably go for "backend-type" = "qemu" under the > backend xenstore directory. I don't have a strong opinion about this. In > the example below I'll use the PV console convention. > > For starters: > > * libxl needs to write the "type" node to xenstore for *all* protocols. > The "type" is not yet configurable. > * qemu reads them for all backends, proceeds if "type" = "ioemu" > > These should be two simple patches. Stage 2: > > * we add options in the xl config file to configure any backend, libxl > set "type" accordingly (Maybe not *any*, but vif, vkbd, vfb could all > have a "type". It is OK if you only add an option for vkbd.) > * non-QEMU backends, in particular Linux backends, also read the "type" > node and proceed if it's "linux" > > Does this sound OK to you? >
On Tue, 18 Apr 2017, Juergen Gross wrote: > On 14/04/17 19:52, Stefano Stabellini wrote: > > On Fri, 14 Apr 2017, Juergen Gross wrote: > >> On 14/04/17 08:06, Oleksandr Andrushchenko wrote: > >>> On 04/14/2017 03:12 AM, Stefano Stabellini wrote: > >>>> On Tue, 11 Apr 2017, Oleksandr Andrushchenko wrote: > >>>>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> > >>>>> > >>>>> For some use cases when Xen framebuffer/input backend > >>>>> is not a part of Qemu it is required to disable it, > >>>>> because of conflicting access to input/display devices. > >>>>> Introduce additional configuration option for explicit > >>>>> input/display control. > >>>> In these cases when you don't want xenfb, why don't you just remove > >>>> "vfb" from the xl config file? QEMU only starts the xenfb backend when > >>>> requested by the toolstack. > >>>> > >>>> Is it because you have an alternative xenfb backend? If so, is it really > >>>> fully xenfb compatible, or is it a different protocol? If it is a > >>>> different protocol, I suggest you rename your frontend/backend PV device > >>>> name to something different from "vfb". > >>>> > >>> Well, offending part is vkbd actually (for multi-touch > >>> we run our own user-space backend which supports > >>> kbd/ptr/mtouch), but vfb and vkbd is the same backend > >>> in QEMU. So, I am ok for vfb, but just want vkbd off > >>> So, there are 2 options: > >>> 1. At compile time remove vkbd and still allow vfb > >>> 2. Remove xenfb completely, if acceptable (this is my case) > >> > >> What about adding a Xenstore entry for backend type and let qemu test > >> for it being not present or containing "qemu"? > > > > That is what we do for the console, using the xenstore node "type". QEMU > > is "ioemu" while xenconsoled is "xenconsoled". Weirdly, instead of a > > backend node, it is a read-only frontend node, see > > tools/libxl/libxl_console.c:libxl__device_console_add. > > > > Oleksandr, I am sorry to feature-creep this simple patch, but I think > > Juergen is right. But we cannot do it just for one protocol. We need to > > introduce a generic way to enable/disable backends in QEMU. Using a > > xenstore node is OK. > > An alternative solution would be similar to qdisk/tap or qusb/vusb > backends: Use different device types on backend side while keeping > frontend side of Xenstore the same as today. > > So today the vkbd backend nodes are: > > /local/domain/0/backend/vkbd/ > > You could use: > > /local/domain/0/backend/mtouch > > and keep the frontend nodes (/local/domain/<n>/device/vkbd/), possibly > with additional feature node(s). > > The qemu backend would have to check for the vkbd backend nodes to be > present before enabling the related backend. Yes, that also works. Either way, we don't have a "registry" of backend protocol nodes; we don't have a doc that ties qdisk with QEMU and the block protocol. We should introduce one before adding any more. > > We could do exactly the same as the PV console, thus "type" = "ioemu", > > read-only, under the frontend xenstore directory. Or we could introduce > > new nodes. I would probably go for "backend-type" = "qemu" under the > > backend xenstore directory. I don't have a strong opinion about this. In > > the example below I'll use the PV console convention. > > > > For starters: > > > > * libxl needs to write the "type" node to xenstore for *all* protocols. > > The "type" is not yet configurable. > > * qemu reads them for all backends, proceeds if "type" = "ioemu" > > > > These should be two simple patches. Stage 2: > > > > * we add options in the xl config file to configure any backend, libxl > > set "type" accordingly (Maybe not *any*, but vif, vkbd, vfb could all > > have a "type". It is OK if you only add an option for vkbd.) > > * non-QEMU backends, in particular Linux backends, also read the "type" > > node and proceed if it's "linux" > > > > Does this sound OK to you? > > >
On 04/14/2017 08:52 PM, Stefano Stabellini wrote: > On Fri, 14 Apr 2017, Juergen Gross wrote: >> On 14/04/17 08:06, Oleksandr Andrushchenko wrote: >>> On 04/14/2017 03:12 AM, Stefano Stabellini wrote: >>>> On Tue, 11 Apr 2017, Oleksandr Andrushchenko wrote: >>>>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> >>>>> >>>>> For some use cases when Xen framebuffer/input backend >>>>> is not a part of Qemu it is required to disable it, >>>>> because of conflicting access to input/display devices. >>>>> Introduce additional configuration option for explicit >>>>> input/display control. >>>> In these cases when you don't want xenfb, why don't you just remove >>>> "vfb" from the xl config file? QEMU only starts the xenfb backend when >>>> requested by the toolstack. >>>> >>>> Is it because you have an alternative xenfb backend? If so, is it really >>>> fully xenfb compatible, or is it a different protocol? If it is a >>>> different protocol, I suggest you rename your frontend/backend PV device >>>> name to something different from "vfb". >>>> >>> Well, offending part is vkbd actually (for multi-touch >>> we run our own user-space backend which supports >>> kbd/ptr/mtouch), but vfb and vkbd is the same backend >>> in QEMU. So, I am ok for vfb, but just want vkbd off >>> So, there are 2 options: >>> 1. At compile time remove vkbd and still allow vfb >>> 2. Remove xenfb completely, if acceptable (this is my case) >> What about adding a Xenstore entry for backend type and let qemu test >> for it being not present or containing "qemu"? sounds reasonable > That is what we do for the console, using the xenstore node "type". QEMU > is "ioemu" while xenconsoled is "xenconsoled". Weirdly, instead of a > backend node, it is a read-only frontend node, see > tools/libxl/libxl_console.c:libxl__device_console_add. > > Oleksandr, I am sorry to feature-creep this simple patch, but I think > Juergen is right. But we cannot do it just for one protocol. We need to > introduce a generic way to enable/disable backends in QEMU. Using a > xenstore node is OK. agree > > We could do exactly the same as the PV console, thus "type" = "ioemu", > read-only, under the frontend xenstore directory. Or we could introduce > new nodes. I would probably go for "backend-type" = "qemu" under the > backend xenstore directory. I don't have a strong opinion about this. In > the example below I'll use the PV console convention. > > For starters: > > * libxl needs to write the "type" node to xenstore for *all* protocols. > The "type" is not yet configurable. > * qemu reads them for all backends, proceeds if "type" = "ioemu" > > These should be two simple patches. Stage 2: > > * we add options in the xl config file to configure any backend, libxl > set "type" accordingly (Maybe not *any*, but vif, vkbd, vfb could all > have a "type". It is OK if you only add an option for vkbd.) > * non-QEMU backends, in particular Linux backends, also read the "type" > node and proceed if it's "linux" > > Does this sound OK to you? For the first take it does, but I'll get back to it a bit later Actually the purpose of the change was to find a way we can live with backends implemented in QEMU and user-space and how they can co-exist Thank you, Oleksandr
diff --git a/configure b/configure index 476210b1b93f..b805cb908f03 100755 --- a/configure +++ b/configure @@ -220,6 +220,7 @@ xen="" xen_ctrl_version="" xen_pv_domain_build="no" xen_pci_passthrough="" +xen_fb_backend="" linux_aio="" cap_ng="" attr="" @@ -909,6 +910,10 @@ for opt do ;; --enable-xen-pv-domain-build) xen_pv_domain_build="yes" ;; + --disable-xen-fb-backend) xen_fb_backend="no" + ;; + --enable-xen-fb-backend) xen_fb_backend="yes" + ;; --disable-brlapi) brlapi="no" ;; --enable-brlapi) brlapi="yes" @@ -1368,6 +1373,7 @@ disabled with --disable-FEATURE, default is enabled if available: virtfs VirtFS xen xen backend driver support xen-pci-passthrough + xen-fb-backend framebuffer/input backend support brlapi BrlAPI (Braile) curl curl connectivity fdt fdt device tree @@ -2213,6 +2219,15 @@ if test "$xen_pv_domain_build" = "yes" && "which requires Xen support." fi +if test "$xen_fb_backend" != "no"; then + if test "$xen" = "yes"; then + xen_fb_backend=yes + else + error_exit "User requested feature Xen framebufer backend support" \ + " but this feature requires Xen support." + fi +fi + ########################################## # Sparse probe if test "$sparse" != "no" ; then @@ -5444,6 +5459,9 @@ if test "$xen" = "yes" ; then if test "$xen_pv_domain_build" = "yes" ; then echo "CONFIG_XEN_PV_DOMAIN_BUILD=y" >> $config_host_mak fi + if test "$xen_fb_backend" = "yes" ; then + echo "CONFIG_XEN_FB_BACKEND=y" >> $config_host_mak + fi fi if test "$linux_aio" = "yes" ; then echo "CONFIG_LINUX_AIO=y" >> $config_host_mak diff --git a/hw/display/Makefile.objs b/hw/display/Makefile.objs index 063889beaf4a..f5ec97ed4f48 100644 --- a/hw/display/Makefile.objs +++ b/hw/display/Makefile.objs @@ -5,7 +5,7 @@ common-obj-$(CONFIG_JAZZ_LED) += jazz_led.o common-obj-$(CONFIG_PL110) += pl110.o common-obj-$(CONFIG_SSD0303) += ssd0303.o common-obj-$(CONFIG_SSD0323) += ssd0323.o -common-obj-$(CONFIG_XEN_BACKEND) += xenfb.o +common-obj-$(CONFIG_XEN_FB_BACKEND) += xenfb.o common-obj-$(CONFIG_VGA_PCI) += vga-pci.o common-obj-$(CONFIG_VGA_ISA) += vga-isa.o diff --git a/hw/xen/xen_backend.c b/hw/xen/xen_backend.c index d1190041ae12..5146cbba6ca5 100644 --- a/hw/xen/xen_backend.c +++ b/hw/xen/xen_backend.c @@ -582,7 +582,9 @@ void xen_be_register_common(void) xen_set_dynamic_sysbus(); xen_be_register("console", &xen_console_ops); +#ifdef CONFIG_XEN_FB_BACKEND xen_be_register("vkbd", &xen_kbdmouse_ops); +#endif xen_be_register("qdisk", &xen_blkdev_ops); #ifdef CONFIG_USB_LIBUSB xen_be_register("qusb", &xen_usb_ops); diff --git a/hw/xenpv/xen_machine_pv.c b/hw/xenpv/xen_machine_pv.c index 79aef4ecc37b..b731344c3f0a 100644 --- a/hw/xenpv/xen_machine_pv.c +++ b/hw/xenpv/xen_machine_pv.c @@ -68,7 +68,9 @@ static void xen_init_pv(MachineState *machine) } xen_be_register_common(); +#ifdef CONFIG_XEN_FB_BACKEND xen_be_register("vfb", &xen_framebuffer_ops); +#endif xen_be_register("qnic", &xen_netdev_ops); /* configure framebuffer */ @@ -95,8 +97,10 @@ static void xen_init_pv(MachineState *machine) /* config cleanup hook */ atexit(xen_config_cleanup); +#ifdef CONFIG_XEN_FB_BACKEND /* setup framebuffer */ xen_init_display(xen_domid); +#endif } static void xenpv_machine_init(MachineClass *mc)