The main differences with the currently implemented method are:
- Requires a local APIC EOI, since it doesn't bypass the local APIC
as the previous method used to do.
- Can be set to use different IDT vectors on each vCPU. Note that
FreeBSD doesn't make use of this feature since the event channel
IDT vector is reserved system wide.
Note that the old method of setting the event channel upcall is
not removed, and will be used as a fallback if this newly introduced
method is not available.
MFC after: 1 month
Sponsored by: Citrix Systems R&D
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
In order to setup an initial environment and jump into the generic
hammer_time initialization function. Some of the code is shared with
PVHv1, while other code is PVHv2 specific.
This allows booting FreeBSD as a PVHv2 DomU and Dom0.
Sponsored by: Citrix Systems R&D
Allow the hypercall page to be initialized very early, even before
vtophys is functional. Also make the function global so it can be
called by other files.
This will be needed in order to perform the early bringup on PVHv2
guests.
Sponsored by: Citrix Systems R&D
HYPERVISOR_start_info is only available to PV and PVHv1 guests, HVM
and PVHv2 guests get this data from HVM parameters that are fetched
using a hypercall.
Instead provide a set of helper functions that should be used to fetch
this data. The helper functions have different implementations
depending on whether FreeBSD is running as PVHv1 or HVM/PVHv2 guest
type.
This helps to cleanup generic Xen code by removing quite a lot of
xen_pv_domain and xen_hvm_domain macro usages.
Sponsored by: Citrix Systems R&D
The PVHv2 entry point is fairly similar to the multiboot1 one. The
kernel is started in protected mode with paging disabled. More
information about the exact BSP state can be found in the pvh.markdown
document on the Xen tree.
This entry point is going to be joined with the native entry point at
hammer_time, and in order to do so the BSP needs to be bootstrapped
into long mode with the same set of page tables as used on bare metal.
Sponsored by: Citrix Systems R&D
This code was left over when it was imported from Linux. The original
committer thought that those functions would be implemented, so the
prototypes where left in place. Delete them at once.
Submitted by: pratyush
Reviewed by: royger
Differential Review: https://reviews.freebsd.org/D15553
Current interface to the gntdev in FreeBSD is wrong, and mostly worked
out of luck before the PTI FreeBSD fixes, when kernel and user-space
where sharing the same page tables.
On FreeBSD ioctls have the size of the passed struct encoded in the
ioctl number, because the generic ioctl handler in the OS takes care
of copying the data from user-space to kernel space, and then calls
the device specific ioctl handler. Thus using ioctl structs with
variable sizes is not possible.
The fix is to turn the array of structs at the end of
ioctl_gntdev_alloc_gref and ioctl_gntdev_map_grant_ref into pointers,
that can be properly accessed from the kernel gntdev driver using the
copyin/copyout functions. Note that this is exactly how it's done for
the privcmd driver.
Sponsored by: Citrix Systems R&D
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
No functional change intended.
Lock the xenstore request mutex when suspending user-space processes, in order
to prevent any process from holding this lock when going into suspension, or
else the xenstore suspend process is going to deadlock.
Submitted by: Liuyingdong <liuyingdong@huawei.com>
Reviewed by: royger
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D9638
When running on Xen, it's possible that a suspend request to the hypervisor
fails (return from HYPERVISOR_suspend different than 0). This means that the
suspend hasn't succeed, and the resume procedure needs to properly handle this
case.
First of all, when such situation happens there's no need to reset the vector
callback, hypercall page, shared info, event channels or grant table, because
it's state is preserved. Also, the PV drivers don't need to be reset to the
initial state, since the connection with the backed has not been interrupted.
Submitted by: Liuyingdong <liuyingdong@huawei.com>
Reviewed by: royger
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D9635
Replace archaic "busses" with modern form "buses."
Intentionally excluded:
* Old/random drivers I didn't recognize
* Old hardware in general
* Use of "busses" in code as identifiers
No functional change.
http://grammarist.com/spelling/buses-busses/
PR: 216099
Reported by: bltsrc at mail.ru
Sponsored by: Dell EMC Isilon
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
A grant-table user-space device will allow user-space applications to map
and share grants (Xen way to share memory) among Xen domains. This grant
table user-space device has been tested with the QEMU Qdisk Xen backed.
Submitted by: jaggi
Reviewed by: royger
Differential review: https://reviews.freebsd.org/D7293
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
This is a license change only commit, which can be found upstream in the Xen
tree as 937324f032f4f77866e80e39de0d697fa5131df1.
Sponsored by: Citrix Systems R&D
Fix two issues with the current event channel code, first ENABLED_SETSIZE is
not correctly defined and then using a BITSET to store the per-cpu masks is
not portable to other arches, since on arm32 the event channel arrays shared
with the hypervisor are of type uint64_t and not long. Partially restore the
previous code but switch the bit operations to use the recently introduced
xen_{set/clear/test}_bit versions.
Reviewed by: Julien Grall <julien.grall@citrix.com>
Sponsored by: Citrix Systems R&D
Differential Revision: https://reviews.freebsd.org/D4080
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
The current Xen console driver is crashing very quickly when using it on
an ARM guest. This is because the console lock is recursive and it may
lead to recursion on the tty lock and/or corrupt the ring pointer.
Furthermore, the console lock is not always taken where it should be and has
to be released too early because of the way the console has been designed.
Over the years, code has been modified to support various new features but
the driver has not been reworked.
This new driver has been rewritten with the idea of only having a small set
of specific function to write either via the shared ring or the hypercall
interface.
Note that HVM support has been left aside for now because it requires
additional features which are not yet supported. A follow-up patch will be
sent with HVM guest support.
List of items that may be good to have but not mandatory:
- Avoid to flush for each character written when using the tty
- Support multiple consoles
Submitted by: Julien Grall <julien.grall@citrix.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D3698
Sponsored by: Citrix Systems R&D
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
Introduce two new loader tunnables that can be used to disable PV disks and
PV nics at boot time. They default to 0 and should be set to 1 (or any
number different than 0) in order to disable the PV devices:
hw.xen.disable_pv_disks=1
hw.xen.disable_pv_nics=1
In /boot/loader.conf will disable both PV disks and nics.
Sponsored by: Citrix Systems R&D
Tested by: Karl Pielorz <kpielorz_lst@tdx.co.uk>
MFC after: 1 week
the blkfront driver to perform I/Os of up to 2 MB, subject to support from
the blkback to which it is connected and the initiation of such large I/Os
by the rest of the kernel. In practice, the I/O size is increased from 40 kB
to 128 kB.
The changes to xen/interface/io/blkif.h consist merely of merging updates
from the upstream Xen repository.
In dev/xen/blkfront/block.h we add some convenience macros and structure
fields used for indirect-page I/Os: The device records its negotiated limit
on the number of indirect pages used, while each I/O command structure gains
permanently allocated page(s) for indirect page references and the Xen grant
references for those pages.
In dev/xen/blkfront/blkfront.c we now check in xbd_queue_cb whether a request
is small enough to handle without an indirection page, and either follow the
previous behaviour or use new code for issuing an indirect segment I/O. In
xbd_connect we read the size of indirect segment I/Os supported by the backend
and select the maximum size we will use; then allocate the pages and Xen grant
references for each I/O command structure. In xbd_free those grants and pages
are released.
A new loader tunable, hw.xbd.xbd_enable_indirect, can be set to 0 in order to
disable this functionality; it works by pretending that the backend does not
support this feature. Some backends exhibit a loss of performance with large
I/Os, so users may wish to test with and without this functionality enabled.
Reviewed by: royger
MFC after: 3 days
Relnotes: yes
The FreeBSD extension adds a new request type, called blkif_segment_block
which has a size of 112bytes for both i386 and amd64. This is fine on
amd64, since requests have a size of 112B there also. But this is not true
for i386, where requests have a size of 108B. So on i386 we basically
overrun the ring slot when queuing a request of type blkif_segment_block_t,
which is very bad.
Remove this extension (including a cleanup of the public blkif.h header
file) from blkfront and blkback.
Sponsored by: Citrix Systems R&D
Tested-by: cperciva
In order to map memory from other domains when running on Xen FreeBSD uses
unused physical memory regions. Until now this memory has been allocated
using bus_alloc_resource, but this is not completely safe as we can end up
using unreclaimed MMIO or ACPI regions.
Fix this by introducing a new newbus method that can be used by Xen drivers
to request for unused memory regions. On amd64 we make sure this memory
comes from regions above 4GB in order to prevent clashes with MMIO/ACPI
regions. On i386 there's nothing we can do, so just fall back to the
previous mechanism.
Sponsored by: Citrix Systems R&D
Tested by: Gustau Pérez <gperez@entel.upc.edu>
This allows the Grant-table code to attach directly to the xenpv bus,
allowing us to remove the grant-table initialization done in xenpv.
Sponsored by: Citrix Systems R&D
Mave the grant table code into the dev/xen folder in preparation for turning
it into a device using the newbus interface. This is just code motion, no
functional changes.
Sponsored by: Citrix Systems R&D
When running as a Xen PVH Dom0 we need to add custom buses that override
some of the functionality present in the ACPI PCI Bus and the PCI Bus. We
currently override the ACPI PCI Bus, but not the PCI Bus, so add a new
override for the PCI Bus and share the generic functions between them.
Reported by: David P. Discher <dpd@dpdtech.com>
Sponsored by: Citrix Systems R&D
conf/files.amd64:
- Add the new files.
x86/xen/xen_pci_bus.c:
- Generic file that contains the PCI overrides so they can be used by the
several PCI specific buses.
xen/xen_pci.h:
- Prototypes for the generic overried functions.
dev/xen/pci/xen_pci.c:
- Xen specific override for the PCI bus.
dev/xen/pci/xen_acpi_pci.c:
- Xen specific override for the ACPI PCI bus.
This device is only attached to priviledged domains, and allows the
toolstack to interact with Xen. The two functions of the privcmd
interface is to allow the execution of hypercalls from user-space, and
the mapping of foreign domain memory.
Sponsored by: Citrix Systems R&D
i386/include/xen/hypercall.h:
amd64/include/xen/hypercall.h:
- Introduce a function to make generic hypercalls into Xen.
xen/interface/xen.h:
xen/interface/memory.h:
- Import the new hypercall XENMEM_add_to_physmap_range used by
auto-translated guests to map memory from foreign domains.
dev/xen/privcmd/privcmd.c:
- This device has the following functions:
- Allow user-space applications to make hypercalls into Xen.
- Allow user-space applications to map memory from foreign domains,
this is accomplished using the newly introduced hypercall
(XENMEM_add_to_physmap_range).
xen/privcmd.h:
- Public ioctl interface for the privcmd device.
x86/xen/hvm.c:
- Remove declaration of hypercall_page, now it's declared in
hypercall.h.
conf/files:
- Add the privcmd device to the build process.
Since Xen and FreeBSD error codes are completely different add a
translation layer in order to convert Xen error codes into native
FreeBSD error codes. This will be used by the privcmd device, which
needs to return the hypercall errors into user-space.
Sponsored by: Citrix Systems R&D
xen/error.h:
- Import Xen error codes.
- Create a table to map Xen error codes into FreeBSD native error
codes.
- Create an inline function that performs the translation.
The user-space event channel device is used by applications to receive
and send event channel interrupts. This device is based on the Linux
evtchn device.
Sponsored by: Citrix Systems R&D
xen/evtchn/evtchn_dev.c:
- Remove the old event channel device, which was already disabled in
the build system.
dev/xen/evtchn/evtchn_dev.c:
- Import a new event channel device based on the one present in
Linux.
- This device allows the following operations:
- Bind VIRQ event channels (ioctl).
- Bind regular event channels (ioctl).
- Create and bind new event channels (ioctl).
- Unbind event channels (ioctl).
- Send notifications to event channels (ioctl).
- Reset the device shared memory ring (ioctl).
- Unmask event channels (write).
- Receive event channel upcalls (read).
- The new code is MP safe, and can be used concurrently.
conf/files:
- Add the new device to the build system.
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.
Convert the xenstore user-space device (/dev/xen/xenstore) to a device
using the newbus interface. This allows us to make the device
initialization dependant on the initialization of xenstore itself in
the kernel.
Sponsored by: Citrix Systems R&D
dev/xen/xenstore/xenstore.c:
- Convert to a newbus device, this removes the xs_dev_init function.
xen/xenstore/xenstore_internal.h:
- Remove xs_dev_init prototype.
dev/xen/xenstore/xenstore.c:
- Don't call xs_dev_init anymore, the device will attach itself when
xenstore is started.
Move xenstore related devices (xenstore.c and xenstore_dev.c) from
xen/xenstore to dev/xen/xenstore. This is just code motion, no
functional changes.
Sponsored by: Citrix Systems R&D
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.
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.
This includes:
o All directories named *ia64*
o All files named *ia64*
o All ia64-specific code guarded by __ia64__
o All ia64-specific makefile logic
o Mention of ia64 in comments and documentation
This excludes:
o Everything under contrib/
o Everything under crypto/
o sys/xen/interface
o sys/sys/elf_common.h
Discussed at: BSDcan
Switch the initialization of gnttab to use an unused physical memory
range for both PVHVM and PVH.
In the past PVHVM was using the xenpci BAR, but there's no reason to
do that, and in fact FreeBSD was probably doing it because it was the
way it was done in Windows, were drivers cannot probably request for
unused physical memory ranges, but it was never enforced in the
hypervisor.
Sponsored by: Citrix Systems R&D
Approved by: gibbs
xen/gnttab.c:
- Allocate contiguous physical memory for grant table frames for both
PVHVM and PVH.
- Since gnttab is not a device, use the xenpv device in order to
request for this allocation.
dev/xen/xenpci/xenpcivar.h:
dev/xen/xenpci/xenpci.c:
- Remove the now unused xenpci_alloc_space and xenpci_alloc_space_int
functions.
xen/gnttab.h:
- Change the prototype of gnttab_init and gnttab_resume, that now
takes a device_t parameter.
dev/xen/control/control.c:
x86/xen/xenpv.c:
- Changes to accomodate the new prototype of gnttab_init and
gnttab_resume.
