Commit Graph

17 Commits

Author SHA1 Message Date
Elliott Mitchell
af610cabf1 xen/intr: adjust xen_intr_handle_upcall() to match driver filter
xen_intr_handle_upcall() has two interfaces.  It needs to be called by
the x86 assembly code invoked by the APIC.  Second, it needs to be called
as a driver_filter_t for the XenPCI code and for architectures besides
x86.

Unfortunately the driver_filter_t interface was implemented as a wrapper
around the x86-APIC interface.  Now create a simple wrapper for the
x86-APIC code, which calls an architecture-independent
xen_intr_handle_upcall().

When called via intr_event_handle(), driver_filter_t functions expect
preemption to be disabled.  This removes the need for
critical_enter()/critical_exit() when called this way.

The lapic_eoi() call is only needed on x86 in some cases when invoked
directly as an APIC vector handler.

Additionally driver_filter_t functions have no need to handle interrupt
counters.  The intrcnt_add() calling function was reworked to match the
current situation.  intrcnt_add() is now only called via one path.

The increment/decrement of curthread->td_intr_nesting_level had
previously been left out.  Appears this was mostly harmless, but this
was noticed during implementation and has been added.

CONFIG_X86 is a leftover from use with Linux.  While the barrier isn't
needed for FreeBSD on x86, it will be needed for FreeBSD on other
architectures.

Copyright note.  xen_intr_intrcnt_add() was introduced at 76acc41fb7
by Justin T. Gibbs.  xen_intrcnt_init() was introduced at fd036deac1
by John Baldwin.

sys/x86/xen/xen_arch_intr.c was originally created by Julien Grall in
2015 for the purpose of holding the x86 interrupt interface.  Later it
was found xen_intr_handle_upcall() was better earlier, and the x86
interrupt interface better later.  As such the filename and header list
belong to Julien Grall, but what those were created for is later.

Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D30006
2023-04-14 15:58:52 +02:00
Elliott Mitchell
ad7dd51499 xen: switch to use headers in contrib
These headers originate with the Xen project and shouldn't be mixed with
the main portion of the FreeBSD kernel. Notably they shouldn't be the
target of clean-up commits.

Switch to use the headers in sys/contrib/xen.

Reviewed by: royger
2022-02-07 10:11:56 +01:00
Roger Pau Monné
ac3ede5371 x86/xen: remove PVHv1 code
PVHv1 was officially removed from Xen in 4.9, so just axe the related
code from FreeBSD.

Note FreeBSD supports PVHv2, which is the replacement for PVHv1.

Sponsored by: Citrix Systems R&D
Reviewed by: kib, Elliott Mitchell
Differential Revision: https://reviews.freebsd.org/D30228
2021-05-17 11:41:21 +02:00
Julien Grall
b55c0d5f56 xen: move x86-specific xen_vector_callback_enabled to sys/x86
This is x86-only and so should not be in the common area.

Submitted by: Elliott Mitchell <ehem+freebsd@m5p.com>
Reviewed by: royger
Differential revision: https://reviews.freebsd.org/D29040
2021-03-15 14:20:21 +01:00
Roger Pau Monné
a74cdf4e74 xen: legacy PVH fixes for the new interrupt count
Register interrupts using the PIC pic_register_sources method instead
of doing it in apic_setup_io. This is now required, since the internal
interrupt structures are not yet setup when calling apic_setup_io.

Approved by:		re (gjb)
Sponsored by:		Citrix Systems R&D
2018-09-13 07:14:11 +00:00
Roger Pau Monné
ca7af67ac9 xen: fix IPI setup with EARLY_AP_STARTUP
Current Xen IPI setup functions require that the caller provide a device in
order to obtain the name of the interrupt from it. With early AP startup this
device is no longer available at the point where IPIs are bound, and a KASSERT
would trigger:

panic: NULL pcpu device_t
cpuid = 0
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xffffffff82233a20
vpanic() at vpanic+0x186/frame 0xffffffff82233aa0
kassert_panic() at kassert_panic+0x126/frame 0xffffffff82233b10
xen_setup_cpus() at xen_setup_cpus+0x5b/frame 0xffffffff82233b50
mi_startup() at mi_startup+0x118/frame 0xffffffff82233b70
btext() at btext+0x2c

Fix this by no longer requiring the presence of a device in order to bind IPIs,
and simply use the "cpuX" format where X is the CPU identifier in order to
describe the interrupt.

Reported by:            sbruno, cperciva
Tested by:              sbruno
X-MFC-With:             r310177
Sponsored by:           Citrix Systems R&D
2016-12-22 16:09:44 +00:00
Roger Pau Monné
0f4d7d9fd7 xen/intr: add reference counts to event channels
Add a reference count to xenisrc. This is required for implementation of
unmap-notifications in the grant table userspace device (gntdev). We need to
hold a reference to the event channel port, in case the user deallocates the
port before we send the notification.

Submitted by:		jaggi
Reviewed by:		royger
Differential review:	https://reviews.freebsd.org/D7429
2016-10-31 13:00:53 +00:00
Roger Pau Monné
2f9ec994bc xen: Code cleanup and small bug fixes
xen/hypervisor.h:
 - Remove unused helpers: MULTI_update_va_mapping, is_initial_xendomain,
   is_running_on_xen
 - Remove unused define CONFIG_X86_PAE
 - Remove unused variable xen_start_info: note that it's used inpcifront
   which is not built at all
 - Remove forward declaration of HYPERVISOR_crash

xen/xen-os.h:
 - Remove unused define CONFIG_X86_PAE
 - Drop unused helpers: test_and_clear_bit, clear_bit,
   force_evtchn_callback
 - Implement a generic version (based on ofed/include/linux/bitops.h) of
   set_bit and test_bit and prefix them by xen_ to avoid any use by other
   code than Xen. Note that It would be worth to investigate a generic
   implementation in FreeBSD.
 - Replace barrier() by __compiler_membar()
 - Replace cpu_relax() by cpu_spinwait(): it's exactly the same as rep;nop
   = pause

xen/xen_intr.h:
 - Move the prototype of xen_intr_handle_upcall in it: Use by all the
   platform

x86/xen/xen_intr.c:
 - Use BITSET* for the enabledbits: Avoid to use custom helpers
 - test_bit/set_bit has been renamed to xen_test_bit/xen_set_bit
 - Don't export the variable xen_intr_pcpu

dev/xen/blkback/blkback.c:
 - Fix the string format when XBB_DEBUG is enabled: host_addr is typed
   uint64_t

dev/xen/balloon/balloon.c:
 - Remove set but not used variable
 - Use the correct type for frame_list: xen_pfn_t represents the frame
   number on any architecture

dev/xen/control/control.c:
 - Return BUS_PROBE_WILDCARD in xs_probe: Returning 0 in a probe callback
   means the driver can handle this device. If by any chance xenstore is the
   first driver, every new device with the driver is unset will use
   xenstore.

dev/xen/grant-table/grant_table.c:
 - Remove unused cmpxchg
 - Drop unused include opt_pmap.h: Doesn't exist on ARM64 and it doesn't
   contain anything required for the code on x86

dev/xen/netfront/netfront.c:
 - Use the correct type for rx_pfn_array: xen_pfn_t represents the frame
   number on any architecture

dev/xen/netback/netback.c:
 - Use the correct type for gmfn: xen_pfn_t represents the frame number on
   any architecture

dev/xen/xenstore/xenstore.c:
 - Return BUS_PROBE_WILDCARD in xctrl_probe: Returning 0 in a probe callback
   means the driver can handle this device. If by any chance xenstore is the
  first driver, every new device with the driver is unset will use xenstore.

Note that with the changes, x86/include/xen/xen-os.h doesn't contain anymore
arch-specific code. Although, a new series will add some helpers that differ
between x86 and ARM64, so I've kept the headers for now.

Submitted by:		Julien Grall <julien.grall@citrix.com>
Reviewed by:		royger
Differential Revision:	https://reviews.freebsd.org/D3921
Sponsored by:		Citrix Systems R&D
2015-10-21 10:44:07 +00:00
Roger Pau Monné
1a52c10530 Update Xen headers from 4.2 to 4.6
Pull the latest headers for Xen which allow us to add support for ARM and
use new features in FreeBSD.

This is a verbatim copy of the xen/include/public so every headers which
don't exits anymore in the Xen repositories have been dropped.

Note the interface version hasn't been bumped, it will be done in a
follow-up. Although, it requires fix in the code to get it compiled:

 - sys/xen/xen_intr.h: evtchn_port_t is already defined in the headers so
   drop it.

 - {amd64,i386}/include/intr_machdep.h: NR_EVENT_CHANNELS now depends on
   xen/interface/event_channel.h, so include it.

 - {amd64,i386}/{amd64,i386}/support.S: It's not neccessary to include
   machine/intr_machdep.h. This is also fixing build compilation with the
   new headers.

 - dev/xen/blkfront/blkfront.c: The typedef for blkif_request_segmenthas
   been dropped. So directly use struct blkif_request_segment

Finally, modify xen/interface/xen-compat.h to throw a preprocessing error if
__XEN_INTERFACE_VERSION__ is not set. This is allow us to catch any file
where xen/xen-os.h is not correctly included.

Submitted by:		Julien Grall <julien.grall@citrix.com>
Reviewed by:		royger
Differential Revision:	https://reviews.freebsd.org/D3805
Sponsored by:		Citrix Systems R&D
2015-10-06 11:29:44 +00:00
Roger Pau Monné
6d54cab1fe xen: allow to register event channels without handlers
This is needed by the event channel user-space device, that requires
registering event channels without unmasking them. intr_add_handler
will unconditionally unmask the event channel, so we avoid calling it
if no filter/handler is provided, and then the user will be in charge
of calling it when ready.

In order to do this, we need to change the opaque type
xen_intr_handle_t to contain the event channel port instead of the
opaque cookie returned by intr_add_handler, since now registration of
event channels without handlers are allowed. The cookie will now be
stored inside of the private xenisrc struct. Also, introduce a new
function called xen_intr_add_handler that allows adding a
filter/handler after the event channel has been registered.

Sponsored by: Citrix Systems R&D

x86/xen/xen_intr.c:
 - Leave the event channel without a handler if no filter/handler is
   provided to xen_intr_bind_isrc.
 - Don't perform an evtchn_mask_port, intr_add_handler will already do
   it.
 - Change the opaque type xen_intr_handle_t to contain a pointer to
   the event channel port number, and make the necessary changes to
   related functions.
 - Introduce a new function called xen_intr_add_handler that can be
   used to add filter/handlers to an event channel after registration.

xen/xen_intr.h:
 - Add prototype of xen_intr_add_handler.
2014-10-22 16:51:52 +00:00
Roger Pau Monné
44e06d158a msi: add Xen MSI implementation
This patch adds support for MSI interrupts when running on Xen. Apart
from adding the Xen related code needed in order to register MSI
interrupts this patch also makes the msi_init function a hook in
init_ops, so different MSI implementations can have different
initialization functions.

Sponsored by: Citrix Systems R&D

xen/interface/physdev.h:
 - Add the MAP_PIRQ_TYPE_MULTI_MSI to map multi-vector MSI to the Xen
   public interface.

x86/include/init.h:
 - Add a hook for setting custom msi_init methods.

amd64/amd64/machdep.c:
i386/i386/machdep.c:
 - Set the default msi_init hook to point to the native MSI
   initialization method.

x86/xen/pv.c:
 - Set the Xen MSI init hook when running as a Xen guest.

x86/x86/local_apic.c:
 - Call the msi_init hook instead of directly calling msi_init.

xen/xen_intr.h:
x86/xen/xen_intr.c:
 - Introduce support for registering/releasing MSI interrupts with
   Xen.
 - The MSI interrupts will use the same PIC as the IO APIC interrupts.

xen/xen_msi.h:
x86/xen/xen_msi.c:
 - Introduce a Xen MSI implementation.

x86/xen/xen_nexus.c:
 - Overwrite the default MSI hooks in the Xen Nexus to use the Xen MSI
   implementation.

x86/xen/xen_pci.c:
 - Introduce a Xen specific PCI bus that inherits from the ACPI PCI
   bus and overwrites the native MSI methods.
 - This is needed because when running under Xen the MSI messages used
   to configure MSI interrupts on PCI devices are written by Xen
   itself.

dev/acpica/acpi_pci.c:
 - Lower the quality of the ACPI PCI bus so the newly introduced Xen
   PCI bus can take over when needed.

conf/files.i386:
conf/files.amd64:
 - Add the newly created files to the build process.
2014-09-30 16:46:45 +00:00
Roger Pau Monné
25e34dd327 xen: implement event channel PIRQ support
This allows Dom0 to manage physical hardware, redirecting the
physical interrupts to event channels.

Sponsored by: Citrix Systems R&D

x86/xen/xen_intr.c:
 - Expand struct xenisrc to hold the level and triggering of PIRQ
   event channels.
 - Implement missing methods in xen_intr_pirq_pic.
 - Allow xen_intr_alloc_isrc to take a vector parameter that globally
   identifies the interrupt. This is only used for PIRQs that are
   bound to a specific hardware IRQ.
 - Introduce xen_register_pirq used to register IO APIC legacy PIRQ
   interrupts.
 - Add support for the dynamic PIRQ EOI map, this shared memory is
   modified by Xen (if it suppoorts that feature), and notifies the
   guest if an EOI is needed or not. If it's not available fall back
   to the old implementation using PHYSDEVOP_irq_status_query.
 - Rename xen_intr_isrc_count to xen_intr_auto_vector_count and
   replace it's usages.
 - Align static variables by name.

xen/xen_intr.h:
 - Add prototype for xen_register_pirq.
2014-08-04 08:42:29 +00:00
Justin T. Gibbs
e44af46e4c Implement PV IPIs for PVHVM guests and further converge PV and HVM
IPI implmementations.

Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Submitted by: gibbs (misc cleanup, table driven config)
Reviewed by:  gibbs
MFC after: 2 weeks

sys/amd64/include/cpufunc.h:
sys/amd64/amd64/pmap.c:
	Move invltlb_globpcid() into cpufunc.h so that it can be
	used by the Xen HVM version of tlb shootdown IPI handlers.

sys/x86/xen/xen_intr.c:
sys/xen/xen_intr.h:
	Rename xen_intr_bind_ipi() to xen_intr_alloc_and_bind_ipi(),
	and remove the ipi vector parameter.  This api allocates
	an event channel port that can be used for ipi services,
	but knows nothing of the actual ipi for which that port
	will be used.  Removing the unused argument and cleaning
	up the comments surrounding its declaration helps clarify
	its actual role.

sys/amd64/amd64/mp_machdep.c:
sys/amd64/include/cpu.h:
sys/i386/i386/mp_machdep.c:
sys/i386/include/cpu.h:
	Implement a generic framework for amd64 and i386 that allows
	the implementation of certain CPU management functions to
	be selected at runtime.  Currently this is only used for
	the ipi send function, which we optimize for Xen when running
	on a Xen hypervisor, but can easily be expanded to support
	more operations.

sys/x86/xen/hvm.c:
	Implement Xen PV IPI handlers and operations, replacing native
	send IPI.

sys/amd64/include/pcpu.h:
sys/i386/include/pcpu.h:
sys/i386/include/smp.h:
	Remove NR_VIRQS and NR_IPIS from FreeBSD headers.  NR_VIRQS
	is defined already for us in the xen interface files.
	NR_IPIS is only needed in one file per Xen platform and is
	easily inferred by the IPI vector table that is defined in
	those files.

sys/i386/xen/mp_machdep.c:
	Restructure to more closely match the HVM implementation by
	performing table driven IPI setup.
2013-09-06 22:17:02 +00:00
Justin T. Gibbs
76acc41fb7 Implement vector callback for PVHVM and unify event channel implementations
Re-structure Xen HVM support so that:
	- Xen is detected and hypercalls can be performed very
	  early in system startup.
	- Xen interrupt services are implemented using FreeBSD's native
	  interrupt delivery infrastructure.
	- the Xen interrupt service implementation is shared between PV
	  and HVM guests.
	- Xen interrupt handlers can optionally use a filter handler
	  in order to avoid the overhead of dispatch to an interrupt
	  thread.
	- interrupt load can be distributed among all available CPUs.
	- the overhead of accessing the emulated local and I/O apics
	  on HVM is removed for event channel port events.
	- a similar optimization can eventually, and fairly easily,
	  be used to optimize MSI.

Early Xen detection, HVM refactoring, PVHVM interrupt infrastructure,
and misc Xen cleanups:

Sponsored by: Spectra Logic Corporation

Unification of PV & HVM interrupt infrastructure, bug fixes,
and misc Xen cleanups:

Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D

sys/x86/x86/local_apic.c:
sys/amd64/include/apicvar.h:
sys/i386/include/apicvar.h:
sys/amd64/amd64/apic_vector.S:
sys/i386/i386/apic_vector.s:
sys/amd64/amd64/machdep.c:
sys/i386/i386/machdep.c:
sys/i386/xen/exception.s:
sys/x86/include/segments.h:
	Reserve IDT vector 0x93 for the Xen event channel upcall
	interrupt handler.  On Hypervisors that support the direct
	vector callback feature, we can request that this vector be
	called directly by an injected HVM interrupt event, instead
	of a simulated PCI interrupt on the Xen platform PCI device.
	This avoids all of the overhead of dealing with the emulated
	I/O APIC and local APIC.  It also means that the Hypervisor
	can inject these events on any CPU, allowing upcalls for
	different ports to be handled in parallel.

sys/amd64/amd64/mp_machdep.c:
sys/i386/i386/mp_machdep.c:
	Map Xen per-vcpu area during AP startup.

sys/amd64/include/intr_machdep.h:
sys/i386/include/intr_machdep.h:
	Increase the FreeBSD IRQ vector table to include space
	for event channel interrupt sources.

sys/amd64/include/pcpu.h:
sys/i386/include/pcpu.h:
	Remove Xen HVM per-cpu variable data.  These fields are now
	allocated via the dynamic per-cpu scheme.  See xen_intr.c
	for details.

sys/amd64/include/xen/hypercall.h:
sys/dev/xen/blkback/blkback.c:
sys/i386/include/xen/xenvar.h:
sys/i386/xen/clock.c:
sys/i386/xen/xen_machdep.c:
sys/xen/gnttab.c:
	Prefer FreeBSD primatives to Linux ones in Xen support code.

sys/amd64/include/xen/xen-os.h:
sys/i386/include/xen/xen-os.h:
sys/xen/xen-os.h:
sys/dev/xen/balloon/balloon.c:
sys/dev/xen/blkback/blkback.c:
sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/console/xencons_ring.c:
sys/dev/xen/control/control.c:
sys/dev/xen/netback/netback.c:
sys/dev/xen/netfront/netfront.c:
sys/dev/xen/xenpci/xenpci.c:
sys/i386/i386/machdep.c:
sys/i386/include/pmap.h:
sys/i386/include/xen/xenfunc.h:
sys/i386/isa/npx.c:
sys/i386/xen/clock.c:
sys/i386/xen/mp_machdep.c:
sys/i386/xen/mptable.c:
sys/i386/xen/xen_clock_util.c:
sys/i386/xen/xen_machdep.c:
sys/i386/xen/xen_rtc.c:
sys/xen/evtchn/evtchn_dev.c:
sys/xen/features.c:
sys/xen/gnttab.c:
sys/xen/gnttab.h:
sys/xen/hvm.h:
sys/xen/xenbus/xenbus.c:
sys/xen/xenbus/xenbus_if.m:
sys/xen/xenbus/xenbusb_front.c:
sys/xen/xenbus/xenbusvar.h:
sys/xen/xenstore/xenstore.c:
sys/xen/xenstore/xenstore_dev.c:
sys/xen/xenstore/xenstorevar.h:
	Pull common Xen OS support functions/settings into xen/xen-os.h.

sys/amd64/include/xen/xen-os.h:
sys/i386/include/xen/xen-os.h:
sys/xen/xen-os.h:
	Remove constants, macros, and functions unused in FreeBSD's Xen
	support.

sys/xen/xen-os.h:
sys/i386/xen/xen_machdep.c:
sys/x86/xen/hvm.c:
	Introduce new functions xen_domain(), xen_pv_domain(), and
	xen_hvm_domain().  These are used in favor of #ifdefs so that
	FreeBSD can dynamically detect and adapt to the presence of
	a hypervisor.  The goal is to have an HVM optimized GENERIC,
	but more is necessary before this is possible.

sys/amd64/amd64/machdep.c:
sys/dev/xen/xenpci/xenpcivar.h:
sys/dev/xen/xenpci/xenpci.c:
sys/x86/xen/hvm.c:
sys/sys/kernel.h:
	Refactor magic ioport, Hypercall table and Hypervisor shared
	information page setup, and move it to a dedicated HVM support
	module.

	HVM mode initialization is now triggered during the
	SI_SUB_HYPERVISOR phase of system startup.  This currently
	occurs just after the kernel VM is fully setup which is
	just enough infrastructure to allow the hypercall table
	and shared info page to be properly mapped.

sys/xen/hvm.h:
sys/x86/xen/hvm.c:
	Add definitions and a method for configuring Hypervisor event
	delievery via a direct vector callback.

sys/amd64/include/xen/xen-os.h:
sys/x86/xen/hvm.c:

sys/conf/files:
sys/conf/files.amd64:
sys/conf/files.i386:
	Adjust kernel build to reflect the refactoring of early
	Xen startup code and Xen interrupt services.

sys/dev/xen/blkback/blkback.c:
sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkfront/block.h:
sys/dev/xen/control/control.c:
sys/dev/xen/evtchn/evtchn_dev.c:
sys/dev/xen/netback/netback.c:
sys/dev/xen/netfront/netfront.c:
sys/xen/xenstore/xenstore.c:
sys/xen/evtchn/evtchn_dev.c:
sys/dev/xen/console/console.c:
sys/dev/xen/console/xencons_ring.c
	Adjust drivers to use new xen_intr_*() API.

sys/dev/xen/blkback/blkback.c:
	Since blkback defers all event handling to a taskqueue,
	convert this task queue to a "fast" taskqueue, and schedule
	it via an interrupt filter.  This avoids an unnecessary
	ithread context switch.

sys/xen/xenstore/xenstore.c:
	The xenstore driver is MPSAFE.  Indicate as much when
	registering its interrupt handler.

sys/xen/xenbus/xenbus.c:
sys/xen/xenbus/xenbusvar.h:
	Remove unused event channel APIs.

sys/xen/evtchn.h:
	Remove all kernel Xen interrupt service API definitions
	from this file.  It is now only used for structure and
	ioctl definitions related to the event channel userland
	device driver.

	Update the definitions in this file to match those from
	NetBSD.  Implementing this interface will be necessary for
	Dom0 support.

sys/xen/evtchn/evtchnvar.h:
	Add a header file for implemenation internal APIs related
	to managing event channels event delivery.  This is used
	to allow, for example, the event channel userland device
	driver to access low-level routines that typical kernel
	consumers of event channel services should never access.

sys/xen/interface/event_channel.h:
sys/xen/xen_intr.h:
	Standardize on the evtchn_port_t type for referring to
	an event channel port id.  In order to prevent low-level
	event channel APIs from leaking to kernel consumers who
	should not have access to this data, the type is defined
	twice: Once in the Xen provided event_channel.h, and again
	in xen/xen_intr.h.  The double declaration is protected by
	__XEN_EVTCHN_PORT_DEFINED__ to ensure it is never declared
	twice within a given compilation unit.

sys/xen/xen_intr.h:
sys/xen/evtchn/evtchn.c:
sys/x86/xen/xen_intr.c:
sys/dev/xen/xenpci/evtchn.c:
sys/dev/xen/xenpci/xenpcivar.h:
	New implementation of Xen interrupt services.  This is
	similar in many respects to the i386 PV implementation with
	the exception that events for bound to event channel ports
	(i.e. not IPI, virtual IRQ, or physical IRQ) are further
	optimized to avoid mask/unmask operations that aren't
	necessary for these edge triggered events.

	Stubs exist for supporting physical IRQ binding, but will
	need additional work before this implementation can be
	fully shared between PV and HVM.

sys/amd64/amd64/mp_machdep.c:
sys/i386/i386/mp_machdep.c:
sys/i386/xen/mp_machdep.c
sys/x86/xen/hvm.c:
	Add support for placing vcpu_info into an arbritary memory
	page instead of using HYPERVISOR_shared_info->vcpu_info.
	This allows the creation of domains with more than 32 vcpus.

sys/i386/i386/machdep.c:
sys/i386/xen/clock.c:
sys/i386/xen/xen_machdep.c:
sys/i386/xen/exception.s:
	Add support for new event channle implementation.
2013-08-29 19:52:18 +00:00
Justin T. Gibbs
ff662b5c98 Improve the Xen para-virtualized device infrastructure of FreeBSD:
o Add support for backend devices (e.g. blkback)
 o Implement extensions to the Xen para-virtualized block API to allow
   for larger and more outstanding I/Os.
 o Import a completely rewritten block back driver with support for fronting
   I/O to both raw devices and files.
 o General cleanup and documentation of the XenBus and XenStore support code.
 o Robustness and performance updates for the block front driver.
 o Fixes to the netfront driver.

Sponsored by: Spectra Logic Corporation

sys/xen/xenbus/init.txt:
	Deleted: This file explains the Linux method for XenBus device
	enumeration and thus does not apply to FreeBSD's NewBus approach.

sys/xen/xenbus/xenbus_probe_backend.c:
	Deleted: Linux version of backend XenBus service routines.  It
	was never ported to FreeBSD.  See xenbusb.c, xenbusb_if.m,
	xenbusb_front.c xenbusb_back.c for details of FreeBSD's XenBus
	support.

sys/xen/xenbus/xenbusvar.h:
sys/xen/xenbus/xenbus_xs.c:
sys/xen/xenbus/xenbus_comms.c:
sys/xen/xenbus/xenbus_comms.h:
sys/xen/xenstore/xenstorevar.h:
sys/xen/xenstore/xenstore.c:
	Split XenStore into its own tree.  XenBus is a software layer built
	on top of XenStore.  The old arrangement and the naming of some
	structures and functions blurred these lines making it difficult to
	discern what services are provided by which layer and at what times
	these services are available (e.g. during system startup and shutdown).

sys/xen/xenbus/xenbus_client.c:
sys/xen/xenbus/xenbus.c:
sys/xen/xenbus/xenbus_probe.c:
sys/xen/xenbus/xenbusb.c:
sys/xen/xenbus/xenbusb.h:
	Split up XenBus code into methods available for use by client
	drivers (xenbus.c) and code used by the XenBus "bus code" to
	enumerate, attach, detach, and service bus drivers.

sys/xen/reboot.c:
sys/dev/xen/control/control.c:
	Add a XenBus front driver for handling shutdown, reboot, suspend, and
	resume events published in the XenStore.  Move all PV suspend/reboot
	support from reboot.c into this driver.

sys/xen/blkif.h:
	New file from Xen vendor with macros and structures used by
	a block back driver to service requests from a VM running a
	different ABI (e.g. amd64 back with i386 front).

sys/conf/files:
	Adjust kernel build spec for new XenBus/XenStore layout and added
	Xen functionality.

sys/dev/xen/balloon/balloon.c:
sys/dev/xen/netfront/netfront.c:
sys/dev/xen/blkfront/blkfront.c:
sys/xen/xenbus/...
sys/xen/xenstore/...
	o Rename XenStore APIs and structures from xenbus_* to xs_*.
	o Adjust to use of M_XENBUS and M_XENSTORE malloc types for allocation
	  of objects returned by these APIs.
	o Adjust for changes in the bus interface for Xen drivers.

sys/xen/xenbus/...
sys/xen/xenstore/...
	Add Doxygen comments for these interfaces and the code that
	implements them.

sys/dev/xen/blkback/blkback.c:
	o Rewrite the Block Back driver to attach properly via newbus,
	  operate correctly in both PV and HVM mode regardless of domain
	  (e.g. can be in a DOM other than 0), and to deal with the latest
	  metadata available in XenStore for block devices.

	o Allow users to specify a file as a backend to blkback, in addition
	  to character devices.  Use the namei lookup of the backend path
	  to automatically configure, based on file type, the appropriate
	  backend method.

	The current implementation is limited to a single outstanding I/O
	at a time to file backed storage.

sys/dev/xen/blkback/blkback.c:
sys/xen/interface/io/blkif.h:
sys/xen/blkif.h:
sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkfront/block.h:
	Extend the Xen blkif API: Negotiable request size and number of
	requests.

	This change extends the information recorded in the XenStore
	allowing block front/back devices to negotiate for optimal I/O
	parameters.  This has been achieved without sacrificing backward
	compatibility with drivers that are unaware of these protocol
	enhancements.  The extensions center around the connection protocol
	which now includes these additions:

	o The back-end device publishes its maximum supported values for,
	  request I/O size, the number of page segments that can be
	  associated with a request, the maximum number of requests that
	  can be concurrently active, and the maximum number of pages that
	  can be in the shared request ring.  These values are published
	  before the back-end enters the XenbusStateInitWait state.

	o The front-end waits for the back-end to enter either the InitWait
	  or Initialize state.  At this point, the front end limits it's
	  own capabilities to the lesser of the values it finds published
	  by the backend, it's own maximums, or, should any back-end data
	  be missing in the store, the values supported by the original
	  protocol.  It then initializes it's internal data structures
	  including allocation of the shared ring, publishes its maximum
	  capabilities to the XenStore and transitions to the Initialized
	  state.

	o The back-end waits for the front-end to enter the Initalized
	  state.  At this point, the back end limits it's own capabilities
	  to the lesser of the values it finds published by the frontend,
	  it's own maximums, or, should any front-end data be missing in
	  the store, the values supported by the original protocol.  It
	  then initializes it's internal data structures, attaches to the
	  shared ring and transitions to the Connected state.

	o The front-end waits for the back-end to enter the Connnected
	  state, transitions itself to the connected state, and can
	  commence I/O.

	Although an updated front-end driver must be aware of the back-end's
	InitWait state, the back-end has been coded such that it can
	tolerate a front-end that skips this step and transitions directly
	to the Initialized state without waiting for the back-end.

sys/xen/interface/io/blkif.h:
	o Increase BLKIF_MAX_SEGMENTS_PER_REQUEST to 255.  This is
	  the maximum number possible without changing the blkif
	  request header structure (nr_segs is a uint8_t).

	o Add two new constants:
	  BLKIF_MAX_SEGMENTS_PER_HEADER_BLOCK, and
	  BLKIF_MAX_SEGMENTS_PER_SEGMENT_BLOCK.  These respectively
	  indicate the number of segments that can fit in the first
	  ring-buffer entry of a request, and for each subsequent
	  (sg element only) ring-buffer entry associated with the
          "header" ring-buffer entry of the request.

	o Add the blkif_request_segment_t typedef for segment
	  elements.

	o Add the BLKRING_GET_SG_REQUEST() macro which wraps the
	  RING_GET_REQUEST() macro and returns a properly cast
	  pointer to an array of blkif_request_segment_ts.

	o Add the BLKIF_SEGS_TO_BLOCKS() macro which calculates the
	  number of ring entries that will be consumed by a blkif
	  request with the given number of segments.

sys/xen/blkif.h:
	o Update for changes in interface/io/blkif.h macros.

	o Update the BLKIF_MAX_RING_REQUESTS() macro to take the
	  ring size as an argument to allow this calculation on
	  multi-page rings.

	o Add a companion macro to BLKIF_MAX_RING_REQUESTS(),
	  BLKIF_RING_PAGES().  This macro determines the number of
	  ring pages required in order to support a ring with the
	  supplied number of request blocks.

sys/dev/xen/blkback/blkback.c:
sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkfront/block.h:
	o Negotiate with the other-end with the following limits:
	      Reqeust Size:   MAXPHYS
	      Max Segments:   (MAXPHYS/PAGE_SIZE) + 1
	      Max Requests:   256
	      Max Ring Pages: Sufficient to support Max Requests with
	                      Max Segments.

	o Dynamically allocate request pools and segemnts-per-request.

	o Update ring allocation/attachment code to support a
	  multi-page shared ring.

	o Update routines that access the shared ring to handle
	  multi-block requests.

sys/dev/xen/blkfront/blkfront.c:
	o Track blkfront allocations in a blkfront driver specific
	  malloc pool.

	o Strip out XenStore transaction retry logic in the
	  connection code.  Transactions only need to be used when
	  the update to multiple XenStore nodes must be atomic.
	  That is not the case here.

	o Fully disable blkif_resume() until it can be fixed
	  properly (it didn't work before this change).

	o Destroy bus-dma objects during device instance tear-down.

	o Properly handle backend devices with powef-of-2 sector
	  sizes larger than 512b.

sys/dev/xen/blkback/blkback.c:
	Advertise support for and implement the BLKIF_OP_WRITE_BARRIER
	and BLKIF_OP_FLUSH_DISKCACHE blkif opcodes using BIO_FLUSH and
	the BIO_ORDERED attribute of bios.

sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkfront/block.h:
	Fix various bugs in blkfront.

       o gnttab_alloc_grant_references() returns 0 for success and
	 non-zero for failure.  The check for < 0 is a leftover
	 Linuxism.

       o When we negotiate with blkback and have to reduce some of our
	 capabilities, print out the original and reduced capability before
	 changing the local capability.  So the user now gets the correct
	 information.

	o Fix blkif_restart_queue_callback() formatting.  Make sure we hold
	  the mutex in that function before calling xb_startio().

	o Fix a couple of KASSERT()s.

        o Fix a check in the xb_remove_* macro to be a little more specific.

sys/xen/gnttab.h:
sys/xen/gnttab.c:
	Define GNTTAB_LIST_END publicly as GRANT_REF_INVALID.

sys/dev/xen/netfront/netfront.c:
	Use GRANT_REF_INVALID instead of driver private definitions of the
	same constant.

sys/xen/gnttab.h:
sys/xen/gnttab.c:
	Add the gnttab_end_foreign_access_references() API.

	This API allows a client to batch the release of an array of grant
	references, instead of coding a private for loop.  The implementation
	takes advantage of this batching to reduce lock overhead to one
	acquisition and release per-batch instead of per-freed grant reference.

	While here, reduce the duration the gnttab_list_lock is held during
	gnttab_free_grant_references() operations.  The search to find the
	tail of the incoming free list does not rely on global state and so
	can be performed without holding the lock.

sys/dev/xen/xenpci/evtchn.c:
sys/dev/xen/evtchn/evtchn.c:
sys/xen/xen_intr.h:
	o Implement the bind_interdomain_evtchn_to_irqhandler API for HVM mode.
	  This allows an HVM domain to serve back end devices to other domains.
	  This API is already implemented for PV mode.

	o Synchronize the API between HVM and PV.

sys/dev/xen/xenpci/xenpci.c:
	o Scan the full region of CPUID space in which the Xen VMM interface
	  may be implemented.  On systems using SuSE as a Dom0 where the
	  Viridian API is also exported, the VMM interface is above the region
	  we used to search.

	o Pass through bus_alloc_resource() calls so that XenBus drivers
	  attaching on an HVM system can allocate unused physical address
	  space from the nexus.  The block back driver makes use of this
	  facility.

sys/i386/xen/xen_machdep.c:
	Use the correct type for accessing the statically mapped xenstore
	metadata.

sys/xen/interface/hvm/params.h:
sys/xen/xenstore/xenstore.c:
	Move hvm_get_parameter() to the correct global header file instead
	of as a private method to the XenStore.

sys/xen/interface/io/protocols.h:
	Sync with vendor.

sys/xeninterface/io/ring.h:
	Add macro for calculating the number of ring pages needed for an N
	deep ring.

	To avoid duplication within the macros, create and use the new
	__RING_HEADER_SIZE() macro.  This macro calculates the size of the
	ring book keeping struct (producer/consumer indexes, etc.) that
	resides at the head of the ring.

	Add the __RING_PAGES() macro which calculates the number of shared
	ring pages required to support a ring with the given number of
	requests.

	These APIs are used to support the multi-page ring version of the
	Xen block API.

sys/xeninterface/io/xenbus.h:
	Add Comments.

sys/xen/xenbus/...
	o Refactor the FreeBSD XenBus support code to allow for both front and
	  backend device attachments.

	o Make use of new config_intr_hook capabilities to allow front and back
	  devices to be probed/attached in parallel.

	o Fix bugs in probe/attach state machine that could cause the system to
	  hang when confronted with a failure either in the local domain or in
	  a remote domain to which one of our driver instances is attaching.

	o Publish all required state to the XenStore on device detach and
	  failure.  The majority of the missing functionality was for serving
	  as a back end since the typical "hot-plug" scripts in Dom0 don't
	  handle the case of cleaning up for a "service domain" that is not
	  itself.

	o Add dynamic sysctl nodes exposing the generic ivars of
	  XenBus devices.

	o Add doxygen style comments to the majority of the code.

	o Cleanup types, formatting, etc.

sys/xen/xenbus/xenbusb.c:
	Common code used by both front and back XenBus busses.

sys/xen/xenbus/xenbusb_if.m:
	Method definitions for a XenBus bus.

sys/xen/xenbus/xenbusb_front.c:
sys/xen/xenbus/xenbusb_back.c:
	XenBus bus specialization for front and back devices.

MFC after:	1 month
2010-10-19 20:53:30 +00:00
Doug Rabson
1267802438 Merge in support for Xen HVM on amd64 architecture. 2009-03-11 15:30:12 +00:00
Kip Macy
3a6d1fcf9c merge 186535, 186537, and 186538 from releng_7_xen
Log:
 - merge in latest xenbus from dfr's xenhvm
 - fix race condition in xs_read_reply by converting tsleep to mtx_sleep

Log:
 unmask evtchn in bind_{virq, ipi}_to_irq

Log:
 - remove code for handling case of not being able to sleep
 - eliminate tsleep - make sleeps atomic
2008-12-29 06:31:03 +00:00