Adapt for NetBSD and add glue for config(9). Enough to get guest domain
virtual devices probed and attached, domain0 and xenstore watch needs to
be done.

branches: 1.1.1;
Initial revision

convert from malloc() to kmem_alloc()

convert the node watch code to use kmem_alloc() instead of malloc()

make xenbus_watch_path() static, it's not used outside xenbus_client.c

in many device attach paths, allocate memory with M_WAITOK instead of M_NOWAIT
and remove code to handle failures that can no longer happen.

branches: 1.13.20;
Make Xen kernels compile without DIAGNOSTIC

branches: 1.12.4;
correct/add protection against snprintf overflow.

branches: 1.11.2; 1.11.12; 1.11.16;
Retire varargs.h support. Move machine/stdarg.h logic into MI
sys/stdarg.h and expect compiler to provide proper builtins, defaulting
to the GCC interface. lint still has a special fallback.
Reduce abuse of _BSD_VA_LIST_ by defining __va_list by default and
derive va_list as required by standards.

sprintf -> snprintf

branches: 1.9.8;
Compile NetBSD/amd64 kernels with "-Wextra". Patches contributed by
Juan RP in PR port-amd64/39266.

branches: 1.8.6; 1.8.10; 1.8.12; 1.8.16;
__FUNCTION__ -> __func__

branches: 1.7.2; 1.7.6;
Pull up the bouyer-xenamd64 branch to HEAD. This brings in amd64 support
to NetBSD/Xen, both Dom0 and DomU.

branches: 1.6.14; 1.6.16; 1.6.20; 1.6.22;
unb0rk build.

branches: 1.5.6; 1.5.12; 1.5.16; 1.5.18;
Add a 'base' argument to xenbus_read_ul, so that we can read number is base
other than 10.

branches: 1.4.2; 1.4.4; 1.4.8; 1.4.10;
Add a xenbus_read_ul() which reads a node and convert it to unsigned long.
Make xenbus_switch_state() and xenbus_read_driver_state() do something usefull.

branches: 1.3.2;
Implement watch of xenstore nodes, and install watches for otherend'state
node.

branches: 1.2.2; 1.2.4;
Adapt for NetBSD and add glue for config(9). Enough to get guest domain
virtual devices probed and attached, domain0 and xenstore watch needs to
be done.

branches: 1.1.1;
Initial revision

xenbus_comms.c: Nix trailing whitespace.

No functional change intended.

xenbus_comms.c: Membar audit.

This had the sense of membars reversed, presumably because xen_rmb
and xen_wmb had gotten reversed at some point.

branches: 1.24.20;
don't reinitialize mutexes/cv on resume

part of PR port-xen/55207

Convert remaining splfoo/splx and tsleep/wakeup to mutex and condvar.
Mark kernel threads and interrupt handlers MPSAFE.

Merge the bouyer-xenpvh branch, bringing in Xen PV drivers support under HVM
guests in GENERIC.
Xen support can be disabled at runtime with
boot -c
disable hypervisor

branches: 1.21.10;
Bifurcate the interrupt establish functions between XEN and non-XEN

Thus intr_establish_xname() becomes xen_intr_establish_xname() etc.

One consequence of this is that dom0 devices expect the native
function calls to be available and we thus provide weak aliasing for
dom0 builds to succeed. XEN and non-XEN devices are distinguished by
the PIC they are established on. XEN interrupts are exclusively
established on xen_pic, while dom0 interrupts are established on
natively available PICs.

This allows us an orthogonal path to xen device management (eg:
xenstore events) in XENPVHVM, without having to worry about unifying
the vector entry paths, etc., which is quite challenging.

Decompose hypervisor_enable_event() into functional steps.

The hypervisor_unmask_event() step is relevant for any event.

The pirq related step is only relevant for pirq bound events.

Prune blanket usage of this, so that usage is semantically appropriate.

When using the intr_establish_xname() interface to register
XEN events, follow established x86/intr.c conventions - set
the 'legacy' irq value to -1, to indicate that the pic, pin
combination (&xen_pic, port) is used for registration.

branches: 1.18.2;
add support for kern.intr.list aka intrctl(8) 'list' for xen

event_set_handler() and pirq_establish() now have extra intrname
parameter; shared intr_create_intrid() is used to provide the value

xen drivers were changed to pass the specific driver instance
name as the xname, e.g. 'vcpu0 clock' instead just 'clock', or
'xencons0' instead of 'xencons'

associated evcnt is now changed to use intrname - this matches native x86

branches: 1.17.2;
Missed a spot: preserve known_mpsafe = (level != IPL_VM).

Noted by kre -- sorry!

Switch XEN drivers to use intr_establish_xname()/intr_disestablish()

This completes the API transition.

KNF. Remove extra spaces. No functional change.

branches: 1.14.12; 1.14.30;
Merge jym-xensuspend branch in -current. ok bouyer@.

Goal: save/restore support in NetBSD domUs, for i386, i386 PAE and amd64.

Executive summary:
- split all Xen drivers (xenbus(4), grant tables, xbd(4), xennet(4))
in two parts: suspend and resume, and hook them to pmf(9).
- modify pmap so that Xen hypervisor does not cry out loud in case
it finds "unexpected" recursive memory mappings
- provide a sysctl(7), machdep.xen.suspend, to command suspend from
userland via powerd(8). Note: a suspend can only be handled correctly
when dom0 requested it, so provide a mechanism that will prevent
kernel to blindly validate user's commands

The code is still in experimental state, use at your own risk: restore
can corrupt backend communications rings; this can completely thrash
dom0 as it will loop at a high interrupt level trying to honor
all domU requests.

XXX PAE suspend does not work in amd64 currently, due to (yet again!)
page validation issues with hypervisor. Will fix.

XXX secondary CPUs are not suspended, I will write the handlers
in sync with cherry's Xen MP work.

Tested under i386 and amd64, bear in mind ring corruption though.

No build break expected, GENERICs and XEN* kernels should be fine.
./build.sh distribution still running. In any case: sorry if it does
break for you, contact me directly for reports.

Remove all return error checks for event_set_handler(...). It either
succeeds or end in panic.

branches: 1.12.2;
Replace x86 memory fences in Xen drivers by their Xen equivalents, to reduce
MD dependency:

x86_lfence() => xen_rmb()
x86_sfence() => xen_wmb()
x86_mfence() => xen_mb()

Discussed in
http://mail-index.netbsd.org/port-xen/2009/01/15/msg004655.html

Ok by bouyer@.

remove unused malloc.h

include <xen/xen.h> for xendomain_is_dom0()

branches: 1.9.2;
- printf -> aprint_*
- fix and add comments
- make some panic/error messages more relevant
- remove last '\n' in DPRINTK() macros, not required as it is already part of format string.

No functional changes.

introduce two macros: xendomain_is_dom0() and xendomain_is_privileged(). Use them.

branches: 1.7.4; 1.7.10;
device_t / softc split
reviewed, tested and approved by bouyer

use aprint_*_dev and device_xname

branches: 1.5.14;
Pull up the bouyer-xenamd64 branch to HEAD. This brings in amd64 support
to NetBSD/Xen, both Dom0 and DomU.

branches: 1.4.2; 1.4.18; 1.4.20; 1.4.24; 1.4.26;
Kill caddr_t; there will be some MI fallout, but it will be fixed shortly.

branches: 1.3.4; 1.3.10; 1.3.16;
Add needed framework for backend drivers.
As we want some control on the name the backend driver will have we
can't use autoconf(9) here. Instead backend drivers registers to
xenbus, which will call a create callback when a new device is there.
Backend devices won't have a "struct device" in xenbus, use a void pointer
instead.

branches: 1.2.4; 1.2.6; 1.2.8; 1.2.10; 1.2.12;
Adapt for NetBSD and add glue for config(9). Enough to get guest domain
virtual devices probed and attached, domain0 and xenstore watch needs to
be done.

branches: 1.1.1;
Initial revision

don't reinitialize mutexes/cv on resume

part of PR port-xen/55207

Convert remaining splfoo/splx and tsleep/wakeup to mutex and condvar.
Mark kernel threads and interrupt handlers MPSAFE.

Merge jym-xensuspend branch in -current. ok bouyer@.

Goal: save/restore support in NetBSD domUs, for i386, i386 PAE and amd64.

Executive summary:
- split all Xen drivers (xenbus(4), grant tables, xbd(4), xennet(4))
in two parts: suspend and resume, and hook them to pmf(9).
- modify pmap so that Xen hypervisor does not cry out loud in case
it finds "unexpected" recursive memory mappings
- provide a sysctl(7), machdep.xen.suspend, to command suspend from
userland via powerd(8). Note: a suspend can only be handled correctly
when dom0 requested it, so provide a mechanism that will prevent
kernel to blindly validate user's commands

The code is still in experimental state, use at your own risk: restore
can corrupt backend communications rings; this can completely thrash
dom0 as it will loop at a high interrupt level trying to honor
all domU requests.

XXX PAE suspend does not work in amd64 currently, due to (yet again!)
page validation issues with hypervisor. Will fix.

XXX secondary CPUs are not suspended, I will write the handlers
in sync with cherry's Xen MP work.

Tested under i386 and amd64, bear in mind ring corruption though.

No build break expected, GENERICs and XEN* kernels should be fine.
./build.sh distribution still running. In any case: sorry if it does
break for you, contact me directly for reports.

branches: 1.5.8;
- rename init_events() to events_init(), to better reflect netbsd semantics

- change unbind_[pv]irq_from_evtch() so that they now return the event
channel the [PV]IRQ was bound to. It reflects the opposite behaviour of the
bind_[pv]irq_to_evtch() functions.

- remove xenbus_suspend() and xenbus_resume() prototypes, as they are not
used anywhere else, and will conflict with the xenbus pmf(9) handlers.

- make start_info aligned on a page boundary, as Xen expects it to be so.

- mask event channel during xbd detach before removing its handler (can
avoid spurious events).

- add the "protocol" entry in xenstore during xbd initialization. Normally
created during domU's boot by xentools, it is under domU's responsibility
in all other cases (save/restore, hot plugging, etc.).

- modifications to xs_init(), so that it can properly return an error.

Reviewed by Christoph (cegger@).

branches: 1.4.4; 1.4.10;
device_t / softc split
reviewed, tested and approved by bouyer

branches: 1.3.2; 1.3.8; 1.3.14; 1.3.68;
start xenbus support for domain0: allocate the page and the event channel,
and export theses via /kern/xen/xsd_mfn and /kern/xen/xsd_port.

branches: 1.2.2; 1.2.4; 1.2.6; 1.2.8;
Adapt for NetBSD and add glue for config(9). Enough to get guest domain
virtual devices probed and attached, domain0 and xenstore watch needs to
be done.

branches: 1.1.1;
Initial revision

fix spelling mistakes, mainly in comments and log messages.

Merge the bouyer-xenpvh branch, bringing in Xen PV drivers support under HVM
guests in GENERIC.
Xen support can be disabled at runtime with
boot -c
disable hypervisor

branches: 1.17.2;
add wrapper to free response from xenbus_dev_request_and_reply(), so
that call in xenbus_dev_write() wouldn't need to know how it's allocated

mostly convert to kmem_alloc()

doing this, remove check for failed allocation with KM_SLEEP, and make
sure to not hold mutex during the call

switch KERNFS_ALLOCENTRY() to use kmem_zalloc() instead of malloc()

branches: 1.14.14;
Avoid variable reassignement; reported by dcb314@hotmail.com in
PR port-xen/52112

xlwp->mtx will never be used in interrupt context; set to IPL_NONE.
avoids a KASSERT when sleeping for the reply.

On second through, it may be possible to have a NULL kfs_v in read and write
(if we're not the LWP which did the open).
Add the appropriate locks and checks.

Fix /kern/xen/xenbus handling. It's badly broken and will do bad things
if more than one thread tries to use it at the same time (hang, memory leak,
panic).
In a kernfs node, the fileops (open, close, read, write) gets a vnode,
but no way to know the file descriptor from which the request comes from.
As /kern/xen/xenbus interface is statefull (write sends a command and read
gets the response), a way to track "clients" is needed.
This commit implement states using the lwp pointer from the caller as a key.
It will fail (with an error) if a kernfs file descriptor is reused by a child
after a fork(), or if a file descriptor is shared by two threads of the same
process but fortunably the xen tools using this interface don't do this.

This should fixes occasional hangs of the Xen tools (one in "xbrd" state,
others in tstile) reported on port-xen by Alaric Snell-Pym.

branches: 1.10.2; 1.10.4;
KNF. Remove extra spaces. No functional change.

branches: 1.9.12; 1.9.30;
Expose Xen kernfs entries inside a domU. Patch originally from sborrill@,
slightly modified by me to profit from runtime checks for dom0 privileges
instead of using compile time macros (DOM0OPS).

It should now be possible to use pkgsrc's sysutils/xentools inside
a domU to query XenStore entries (or even modify part of it if the domain
has enough rights).

ansify function definitions

branches: 1.7.18; 1.7.26; 1.7.28; 1.7.32;
a_l -> curlwp

Pull up the bouyer-xenamd64 branch to HEAD. This brings in amd64 support
to NetBSD/Xen, both Dom0 and DomU.

branches: 1.5.6; 1.5.12; 1.5.22; 1.5.40; 1.5.42; 1.5.46; 1.5.48;
Fix read for /kern/xen/xenbus: ignore offset.

Add dom0 operation support for Xen3. Probably buggy, but it's enouth to have
xend and xenstored starting; xm info and xm list works.

branches: 1.3.2;
Centralize all xenbus /kern entries in xenbus_dev.c, and call
xenbus_kernfs_init() for domain0. Now /kern/xen/xenbus is also present
on domain0.

branches: 1.2.2; 1.2.4; 1.2.6; 1.2.8;
Adapt for NetBSD and add glue for config(9). Enough to get guest domain
virtual devices probed and attached, domain0 and xenstore watch needs to
be done.

branches: 1.1.1;
Initial revision

Ignore cdroms only for VM_GUEST_XENPVHVM guests, not for all !XENPV kernels
(we can also have PVH guests with !XENPV kernels)

cdroms as xbd devices are skipped in PVHVM mode to avoid hangs if they
are not ready, i.e. do not contain an ISO image (that they hang is a bug
that should be fixed in itself). They are instead detected as an emulated
cdX which does deal with not being ready.

This leads to a regression in pure PV mode where xbd devices are hot-plugged
when an ISO is mounted and there are no emulated block devices such as cdX.
The xbd devices never appear and thus ISO images are not accessible.

Revert to pre-10 behaviour on pure PV kernels.

branches: 1.60.6;
xenbus: if dom0 support is not compiled in, panic with a usefull message
instead of waiting for an event which will never happen

don't test arrays against NULL.

found by GCC 12.

branches: 1.58.6;
Merge thorpej-cfargs2.

branches: 1.57.2;
Grab KERNEL_LOCK before calling config_found()

branches: 1.56.2;
Merge thorpej-cfargs branch:

Simplify and make extensible the config_search() / config_found() /
config_attach() interfaces: rather than having different variants for
which arguments you want pass along, just have a single call that
takes a variadic list of tag-value arguments.

Adjust all call sites:
- Simplify wherever possible; don't pass along arguments that aren't
actually needed.
- Don't be explicit about what interface attribute is attaching if
the device only has one. (More simplification.)
- Add a config_probe() function to be used in indirect configuiration
situations, making is visibly easier to see when indirect config is
in play, and allowing for future change in semantics. (As of now,
this is just a wrapper around config_match(), but that is an
implementation detail.)

Remove unnecessary or redundant interface attributes where they're not
needed.

There are currently 5 "cfargs" defined:
- CFARG_SUBMATCH (submatch function for direct config)
- CFARG_SEARCH (search function for indirect config)
- CFARG_IATTR (interface attribte)
- CFARG_LOCATORS (locators array)
- CFARG_DEVHANDLE (devhandle_t - wraps OFW, ACPI, etc. handles)

...and a sentinel value CFARG_EOL.

Add some extra sanity checking to ensure that interface attributes
aren't ambiguous.

Use CFARG_DEVHANDLE in MI FDT, OFW, and ACPI code, and macppc and shark
ports to associate those device handles with device_t instance. This
will trickle trough to more places over time (need back-end for pre-OFW
Sun OBP; any others?).

branches: 1.55.4;
Add need-flags for kernfs.
Compile Xen kernfs support only if kernfs is compiled in the kernel.
Should fix MODULAR build.

fix compile when DPRINK() is defined

don't reinitialize mutexes/cv on resume

part of PR port-xen/55207

Convert remaining splfoo/splx and tsleep/wakeup to mutex and condvar.
Mark kernel threads and interrupt handlers MPSAFE.

Skip block device with device-type "cdrom", as their emulation can't be
disabled; and the backend driver doesn't handle them either.
Fix hang when booting with 'ioemu:hdc:cdrom' type disks.
While there convert some printf to aprint_error()

Merge the bouyer-xenpvh branch, bringing in Xen PV drivers support under HVM
guests in GENERIC.
Xen support can be disabled at runtime with
boot -c
disable hypervisor

put xenbus dmat into xenbus_device so it's available also for backend
devices which don't use autoconfig, remove from attach args

add and pass dma tag to PV drivers attached to xenbus, so thay can
use bus_dmamap_load_mbuf() et.al.

due to XENPV override, _BUS_BUS_TO_PHYS() dmamap segment ds_addr
gets filled with ma, so value can be directly used for e.g. grant calls

g/c unused xenwatch_mutex extern, and streq()

branches: 1.46.2;
add a small wrapper xenbus_directory_free() to free result of
xenbus_directory(), so that caller doesn't need to be aware how the memory
was allocated

partially convert to kmem_alloc()

plug memory leak in one xenbus_probe_device_type() error path
when read_backend_details() fails

convert the node watch code to use kmem_alloc() instead of malloc()

revert the watch.node change, xenbus_watch_path() and xenbus_watch_path2()
need to use non-constant path

change xenbus_read() interface so that caller supplies the buffer and it's
size, caller doesn't free(9) the returned value any more

no need to malloc()+copy watch.node, it's constant string - either "device"
or "backend"; just use the strings direct

Compute storage size for a string correctly.

branches: 1.39.18;
KNF. Remove extra spaces. No functional change.

branches: 1.38.6;
Catch up to recent changes in config_pending_{incr,decr}().

branches: 1.37.2; 1.37.4;
Fix problem where devices with ID 0 were skipped as invalid as it didn't
distinguish between numerical zero and invalid numeric string.

Sort vif and vbd device IDs numerically so that attach order does not depend
on the order they are passed in through xenstore. While this works for
hand-crafted Xen configuration files, it does not work for XenServer, XCP or
EC2 instances. This means that adding an extra virtual disk can make the
domU unbootable.

ID is actually based on the Linux device major/minor so this approach isn't
entirely correct (for instance, you can specify devices to be non-contiguous
which doesn't fit too well with our autoconf approach), but it works as a
first approximation.

Tested by me on XenServer and riz@ on EC2. OK bouyer@

branches: 1.35.2; 1.35.8;
Expose Xen kernfs entries inside a domU. Patch originally from sborrill@,
slightly modified by me to profit from runtime checks for dom0 privileges
instead of using compile time macros (DOM0OPS).

It should now be possible to use pkgsrc's sysutils/xentools inside
a domU to query XenStore entries (or even modify part of it if the domain
has enough rights).

Merge jym-xensuspend branch in -current. ok bouyer@.

Goal: save/restore support in NetBSD domUs, for i386, i386 PAE and amd64.

Executive summary:
- split all Xen drivers (xenbus(4), grant tables, xbd(4), xennet(4))
in two parts: suspend and resume, and hook them to pmf(9).
- modify pmap so that Xen hypervisor does not cry out loud in case
it finds "unexpected" recursive memory mappings
- provide a sysctl(7), machdep.xen.suspend, to command suspend from
userland via powerd(8). Note: a suspend can only be handled correctly
when dom0 requested it, so provide a mechanism that will prevent
kernel to blindly validate user's commands

The code is still in experimental state, use at your own risk: restore
can corrupt backend communications rings; this can completely thrash
dom0 as it will loop at a high interrupt level trying to honor
all domU requests.

XXX PAE suspend does not work in amd64 currently, due to (yet again!)
page validation issues with hypervisor. Will fix.

XXX secondary CPUs are not suspended, I will write the handlers
in sync with cherry's Xen MP work.

Tested under i386 and amd64, bear in mind ring corruption though.

No build break expected, GENERICs and XEN* kernels should be fine.
./build.sh distribution still running. In any case: sorry if it does
break for you, contact me directly for reports.

Retire varargs.h support. Move machine/stdarg.h logic into MI
sys/stdarg.h and expect compiler to provide proper builtins, defaulting
to the GCC interface. lint still has a special fallback.
Reduce abuse of _BSD_VA_LIST_ by defining __va_list by default and
derive va_list as required by standards.

Large rewrite of the balloon driver. This one:

- turns balloon into a driver that attaches to xenbus(4). This allows to
disable the functionality either at compile time or boot time via
userconf(4). Driver can implement detach or pmf(9) hooks if deemed
necessary.

- keeps Cherry's locking model, but simplify it a bit. There is now
only one target value serialized inside balloon, we do not feedback
alternative value to Xenstore (clients are not expected to see its value
evolve behind their back, and can't do much about that either)

- implements min threshold; this is an admin-settable value that tells
driver to "not balloon below this threshold." This can be used by domain
to keep memory reservations, useful if activity is expected in the near
future.

- in addition to min threshold, the driver implements internally a
safeguard value (uvmexp.freemin + 1MiB), so that admin cannot
inadvertently set min to a very low value forcing domain into heavy
memory pressure and swapping.

- create the sysctl(8) kern.xen.balloon tree. 4 nodes are actually present
(values are in KiB):
- min: (rw) an admin-settable value that prevents ballooning below this
mark
- max: (ro) the maximum size for reservation, as set by xm(1) mem-max.
- current: (ro) the current reservation for domain.
- target: (rw) the targetted reservation for domain.

- fix a few limitations here and there, most notably the max_reservation
hypercall, and KiB vs pages representations at interfaces.

The driver is still turned off by default. Enabling it would need more
approval, especially from bouyer@, cherry@ and cegger@.

FWIW: tested it two days long, from amd64 dom0 (with dom0 ballooning
enabled for xend), and bunch of domUs. Did not notice anything suspicious.

XXX it still has one big limitation: it cannot hotplug memory pages in
uvm(9) if they were not present beforehand. Example: ballooning above
physmem will give more pages to domain but it won't use it to serve
allocations, unless we teach uvm(9) how to handle the extra pages.

previous fix does not work if there is exactly only one entry where continue
exits the loop.
Apply fix from Konrad Wilke on port-xen@
That makes NetBSD DomU boot on Linux Dom0 with xl.

Continue scanning for other frontends when initialization
of one frontend failed. Bug reported by Konrad Wilk on port-xen@.
Fix this for all error pathes within the loop.

(purely cosmetic changes)

- Use free_otherend_details() instead of calling free() on xbusd_otherend.
- rename talk_to_otherend() to watch_otherend(). We register a watch for
changes in the otherend device "state"; we are not really talking to it.
- add missing prototypes.

branches: 1.28.2;
The Xen balloon driver enables growing and shrinking
PV domains on the fly, by collaborating with UVM and the hypervisor

branches: 1.27.2; 1.27.4; 1.27.6;
Do not probe for console when configuring xenbus devices, as it is
attached earlier during boot, when initializing hypervisor.

This avoids the "unknown type console at xenbus0 id 0 not configured"
autoconf(9) messages, which are misleading during domU's boot.

See also http://mail-index.netbsd.org/port-xen/2009/01/05/msg004621.html

Ok by bouyer@ in private mail.

branches: 1.26.2;
include <xen/xen.h> for xendomain_is_dom0()

branches: 1.25.2;
- rename init_events() to events_init(), to better reflect netbsd semantics

- change unbind_[pv]irq_from_evtch() so that they now return the event
channel the [PV]IRQ was bound to. It reflects the opposite behaviour of the
bind_[pv]irq_to_evtch() functions.

- remove xenbus_suspend() and xenbus_resume() prototypes, as they are not
used anywhere else, and will conflict with the xenbus pmf(9) handlers.

- make start_info aligned on a page boundary, as Xen expects it to be so.

- mask event channel during xbd detach before removing its handler (can
avoid spurious events).

- add the "protocol" entry in xenstore during xbd initialization. Normally
created during domU's boot by xentools, it is under domU's responsibility
in all other cases (save/restore, hot plugging, etc.).

- modifications to xs_init(), so that it can properly return an error.

Reviewed by Christoph (cegger@).

The 'sc' in xenbus_sc implies a softc, but it is actually a device_t. Since the device_t/softc split you can't cast a softc out of a device and vice versa.
Therefore rename xenbus_sc to xenbus_dev to prevent any possible confusions.

xenbus_probe_init():
- use xendomain_is_dom0() (from jym@)
- replace return with kthread_exit(0) (from jym@)
- cleanup error handling
- plug memory leak in error path
- use aprint_error_dev for error messages (from jym@)

xenbus_attach():
- use aprint_error_dev for error message

Compile NetBSD/amd64 kernels with "-Wextra". Patches contributed by
Juan RP in PR port-amd64/39266.

branches: 1.21.4;
Dom0: Add a delay before registering event handlers. Wait 1s per request from bouyer.

Fixes "Hotplug scripts not working" problems when launching guests.
Reviewed by bouyer.

branches: 1.20.2; 1.20.4; 1.20.6;
device_t / softc split
reviewed, tested and approved by bouyer

use aprint_*_dev and device_xname

branches: 1.18.6;
__FUNCTION__ -> __func__

branches: 1.17.2; 1.17.6;
Pull up the bouyer-xenamd64 branch to HEAD. This brings in amd64 support
to NetBSD/Xen, both Dom0 and DomU.

branches: 1.16.2;
Merge the ppcoea-renovation branch to HEAD.

This branch was a major cleanup and rototill of many of the various OEA
cpu based PPC ports that focused on sharing as much code as possible
between the various ports to eliminate near-identical copies of files in
every tree. Additionally there is a new PIC system that unifies the
interface to interrupt code for all different OEA ppc arches. The work
for this branch was done by a variety of people, too long to list here.

TODO:
bebox still needs work to complete the transition to -renovation.
ofppc still needs a bunch of work, which I will be looking at.
ev64260 still needs to be renovated
amigappc was not attempted.

NOTES:
pmppc was removed as an arch, and moved to a evbppc target.

branches: 1.15.8; 1.15.10; 1.15.14;
Merge some of the less invasive changes from the vmlocking branch:

- kthread, callout, devsw API changes
- select()/poll() improvements
- miscellaneous MT safety improvements

branches: 1.14.8; 1.14.10; 1.14.16;
Coverity CID 3786: Fix memory leak (from Arnaud Lacombe)

branches: 1.13.2; 1.13.4; 1.13.6;
"xm shutdown" support for xen3. ok'ed by Manuel Bouyer.

branches: 1.12.2;
Add a 'base' argument to xenbus_read_ul, so that we can read number is base
other than 10.

branches: 1.11.2; 1.11.4;
Add needed framework for backend drivers.
As we want some control on the name the backend driver will have we
can't use autoconf(9) here. Instead backend drivers registers to
xenbus, which will call a create callback when a new device is there.
Backend devices won't have a "struct device" in xenbus, use a void pointer
instead.

branches: 1.10.2;
Call xb_init_comms() once the event channel has been allocated for dom0.

branches: 1.9.2;
Centralize all xenbus /kern entries in xenbus_dev.c, and call
xenbus_kernfs_init() for domain0. Now /kern/xen/xenbus is also present
on domain0.

Move xenkernfs_init() back in hypervisor.c so that /kern/xen/privcmd can
also register properly.

start xenbus support for domain0: allocate the page and the event channel,
and export theses via /kern/xen/xsd_mfn and /kern/xen/xsd_port.

#if out read_frontend_details() for now, so that it compiles with DOM0OPS.

branches: 1.5.2;
Properly handle dynamic attach/detach of device:
- keep a linked list of xenbus_device in the xenbus_infrastructure, and
keep a pointer to struct device for each xenbus_device
- xenbus_probe_device_type(): check that the device is not already attached
- when we get a frontend_changed callback, call xenbus_probe_device_type()
- When a device changes to state XenbusStateClosed, config_detach() it
and free the structures.
While there, move xbusd_path[] to the end of struct xenbus_device, and
allocate only the space needed to store the path. Garbage-collect
struct xenbus_driver, it's not needed.

Initialize memory to 0 when allocating a new xenbus device structure.
Prevents trying to unregister a nonexistant node in talk_to_otherend().

branches: 1.3.2;
Implement watch of xenstore nodes, and install watches for otherend'state
node.

branches: 1.2.2; 1.2.4;
Adapt for NetBSD and add glue for config(9). Enough to get guest domain
virtual devices probed and attached, domain0 and xenstore watch needs to
be done.

branches: 1.1.1;
Initial revision

process_msg() is called from thread context, so malloc() can wait for
memory. Should avoids occasional ENOMEM reading messages

Convert remaining splfoo/splx and tsleep/wakeup to mutex and condvar.
Mark kernel threads and interrupt handlers MPSAFE.

add wrapper to free response from xenbus_dev_request_and_reply(), so
that call in xenbus_dev_write() wouldn't need to know how it's allocated

add a small wrapper xenbus_directory_free() to free result of
xenbus_directory(), so that caller doesn't need to be aware how the memory
was allocated

change xenbus_read() interface so that caller supplies the buffer and it's
size, caller doesn't free(9) the returned value any more

branches: 1.23.38;
xen: prevent adding duplicate xenwatches

When a xenstore watch triggers, the event is processed on process_msg
and if a valid handle it's found the handler is queued for execution
on the pending xen watches queue (watch_events).

This may present a problem if we trigger a xenwatch several times and
then disconnect the device. If several xenwatch events are added to
the watch_events queue and the device is disconnected afterwards, the
first processed xenwatch event will disconnect the device, remove the
watch and free all resources. This triggers a panic if there are
pending xenwatch events for that device already queued in the local
queue of the function xenwatch_thread, since when the next watch that
has the same handler tries to execute we get a panic due to the fact
that the device is already disconnected and all resources had been
freed:

xenbus_watch: 0xffffa0000b7cd1d0
xbw_callback: 0xffffffff80755dd4
otherend_changed: backend/vif/1/0
backend/vif/1/0/state 6
backend/vif/1/0 -> Closed
backend/vif/1/0 -> backend_device, b_detach: 0xffffffff8075a2bf
xenbus_watch: 0xffffa0000b7cd1d0
xbw_callback: 0xfc5ec02183e547a8
fatal protection fault in supervisor mode
trap type 4 code 0 rip ffffffff80756596 cs e030 rflags 10246 cr2
7f7ff7b4c020 ilevel 0 rsp ffffa000e6d82c50
curlwp 0xffffa0000a72d580 pid 0 lid 36 lowest kstack
0xffffa000e6d7f000
kernel: protection fault trap, code=0
Stopped in pid 0.36 (system) at netbsd:xenwatch_thread+0xc7: call
*10(%rax
)
xenwatch_thread() at netbsd:xenwatch_thread+0xc7
ds f
es 5987
fs 2c40
gs 1460
rdi ffffa0000b7cd1d0
rsi ffffa0000a5477f0
rbp ffffa000e6d82c70
rbx ffffa0000b7c14c0
rdx 2
rcx f
rax ffffa0000b7cd1d0
r8 78
r9 ffffffef
r10 deadbeef
r11 1
r12 ffffa000e6d82c50
r13 ffffa0000a72d580
r14 ffffa0000a72d580
r15 0
rip ffffffff80756596 xenwatch_thread+0xc7
cs e030
rflags 10246
rsp ffffa000e6d82c50
ss e02b
netbsd:xenwatch_thread+0xc7: call *10(%rax)

branches: 1.22.2; 1.22.8; 1.22.12; 1.22.14;
Change a cast to appease gcc4.5

Retire varargs.h support. Move machine/stdarg.h logic into MI
sys/stdarg.h and expect compiler to provide proper builtins, defaulting
to the GCC interface. lint still has a special fallback.
Reduce abuse of _BSD_VA_LIST_ by defining __va_list by default and
derive va_list as required by standards.

check that the list is empty before calling cv_wait(). Otherwise
we may sleep waiting for an event which is already in the queue.

branches: 1.19.2;
- Replace uses of simple_lock and ltsleep with mutex and condvar.
- Improve some parts of the code to be more MP-friendly.

Tested by jakllsch@.

branches: 1.18.4; 1.18.6;
sprintf -> snprintf

branches: 1.17.6;
include <xen/xen.h> for xendomain_is_dom0()

branches: 1.16.2;
- rename init_events() to events_init(), to better reflect netbsd semantics

- change unbind_[pv]irq_from_evtch() so that they now return the event
channel the [PV]IRQ was bound to. It reflects the opposite behaviour of the
bind_[pv]irq_to_evtch() functions.

- remove xenbus_suspend() and xenbus_resume() prototypes, as they are not
used anywhere else, and will conflict with the xenbus pmf(9) handlers.

- make start_info aligned on a page boundary, as Xen expects it to be so.

- mask event channel during xbd detach before removing its handler (can
avoid spurious events).

- add the "protocol" entry in xenstore during xbd initialization. Normally
created during domU's boot by xentools, it is under domU's responsibility
in all other cases (save/restore, hot plugging, etc.).

- modifications to xs_init(), so that it can properly return an error.

Reviewed by Christoph (cegger@).

- printf -> aprint_*
- fix and add comments
- make some panic/error messages more relevant
- remove last '\n' in DPRINTK() macros, not required as it is already part of format string.

No functional changes.

branches: 1.14.4; 1.14.10;
Add swedge support to xbd backed, and make the virtual block device handle
sizes larger than 4TB. Tested by Jukka Marin.
Should fix kern/37370.

branches: 1.13.2; 1.13.6;
Merge the bouyer-xeni386 branch to head, at tag bouyer-xeni386-merge1 (the
branch is still active and will see i386PAE support developement).
Sumary of changes:
- switch xeni386 to the x86/x86/pmap.c, and the xen/x86/x86_xpmap.c
pmap bootstrap.
- merge back most of xen/i386/ to i386/i386
- change the build to reduce diffs between i386 and amd64 in file locations
- remove include files that were identical to the i386/amd64 counterparts,
the build will find them via the xen-ma/machine link.

__FUNCTION__ -> __func__

branches: 1.11.4;
lockmgr -> mutex

branches: 1.10.2;
Pull up the bouyer-xenamd64 branch to HEAD. This brings in amd64 support
to NetBSD/Xen, both Dom0 and DomU.

branches: 1.9.2;
Merge the ppcoea-renovation branch to HEAD.

This branch was a major cleanup and rototill of many of the various OEA
cpu based PPC ports that focused on sharing as much code as possible
between the various ports to eliminate near-identical copies of files in
every tree. Additionally there is a new PIC system that unifies the
interface to interrupt code for all different OEA ppc arches. The work
for this branch was done by a variety of people, too long to list here.

TODO:
bebox still needs work to complete the transition to -renovation.
ofppc still needs a bunch of work, which I will be looking at.
ev64260 still needs to be renovated
amigappc was not attempted.

NOTES:
pmppc was removed as an arch, and moved to a evbppc target.

branches: 1.8.8; 1.8.10; 1.8.14;
Looks like this was part of a botched merge; apply he@'s patch to make
everything compile/link again.

Merge some of the less invasive changes from the vmlocking branch:

- kthread, callout, devsw API changes
- select()/poll() improvements
- miscellaneous MT safety improvements

branches: 1.6.6; 1.6.10; 1.6.16; 1.6.18; 1.6.20; 1.6.24; 1.6.26;
Add a 'base' argument to xenbus_read_ul, so that we can read number is base
other than 10.

branches: 1.5.2; 1.5.4; 1.5.8; 1.5.10;
unregister_xenbus_watch(): Ops, correct code to remove pending watch events
so that it's not an infinite loop.

Add a xenbus_read_ul() which reads a node and convert it to unsigned long.
Make xenbus_switch_state() and xenbus_read_driver_state() do something usefull.

branches: 1.3.2;
Implement watch of xenstore nodes, and install watches for otherend'state
node.

branches: 1.2.2; 1.2.4;
Adapt for NetBSD and add glue for config(9). Enough to get guest domain
virtual devices probed and attached, domain0 and xenstore watch needs to
be done.

branches: 1.1.1;
Initial revision