In its stead use the Solaris / illumos approach of emulating '-' (dash)
in probe names with '__' (two consecutive underscores).
Reviewed by: markj
MFC after: 3 weeks
option, unbreak the lock tracing release semantic by embedding
calls to LOCKSTAT_PROFILE_RELEASE_LOCK() direclty in the inlined
version of the releasing functions for mutex, rwlock and sxlock.
Failing to do so skips the lockstat_probe_func invokation for
unlocking.
- As part of the LOCKSTAT support is inlined in mutex operation, for
kernel compiled without lock debugging options, potentially every
consumer must be compiled including opt_kdtrace.h.
Fix this by moving KDTRACE_HOOKS into opt_global.h and remove the
dependency by opt_kdtrace.h for all files, as now only KDTRACE_FRAMES
is linked there and it is only used as a compile-time stub [0].
[0] immediately shows some new bug as DTRACE-derived support for debug
in sfxge is broken and it was never really tested. As it was not
including correctly opt_kdtrace.h before it was never enabled so it
was kept broken for a while. Fix this by using a protection stub,
leaving sfxge driver authors the responsibility for fixing it
appropriately [1].
Sponsored by: EMC / Isilon storage division
Discussed with: rstone
[0] Reported by: rstone
[1] Discussed with: philip
sys/dev/xen/balloon/balloon.c:
Remove unused and commented out code.
Fix deadlock caused by performing a sleepable malloc
while holding the balloon mutex.
Perform proper accounting of the memory used by the domain.
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
MFC after: 2 days
makes FreeBSD halt but not poweroff (as expected when issuing a
shutdown from the VM manager). Fix this by using the same handler
for both "halt" and "poweroff".
NB: The "halt" signal seems to be used on XenServer only. The OSS
Xen toolstack (xl) uses "poweroff" instead.
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
MFC after: 2 days
resist easy conversion since they implement a great deal of their attach
logic inside probe(). Some of this could be fixed by moving it to attach(),
but some requires something more subtle than BUS_PROBE_NOWILDCARD.
This shuld have been a problem since r230587. Not exactly sure why it
was not detected the last weeks with the tinderbox. I would assume
r255744 is what started to cause it.
MFC after: 1 week
prior releases.
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
Approved by: re (gjb)
sys/dev/xen/blkfront/blkfront.c:
On XenServer versions up to an including 6.2, paravirtualized
CDROM support is broken. When running in an HVM domain,
ignore paravirtualized instances of CDROM media, and instead
rely on native drivers attaching to emulated hardware. This
functions correctly on all currently known Xen based
platforms.
field. Perform vcpu enumeration for Xen PV and HVM environments
and convert all Xen drivers to use vcpu_id instead of a hard coded
assumption of the mapping algorithm (acpi or apic ID) in use.
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
Approved by: re (blanket Xen)
amd64/include/pcpu.h:
i386/include/pcpu.h:
Add vcpu_id to the amd64 and i386 pcpu structures.
dev/xen/timer/timer.c
x86/xen/xen_intr.c
Use new vcpu_id instead of assuming acpi_id == vcpu_id.
i386/xen/mp_machdep.c:
i386/xen/mptable.c
x86/xen/hvm.c:
Perform Xen HVM and Xen full PV vcpu_id mapping.
x86/xen/hvm.c:
x86/acpica/madt.c
Change SYSINIT ordering of acpi CPU enumeration so that it
is guaranteed to be available at the time of Xen HVM vcpu
id mapping.
Xen PVHVM guest.
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
Approved by: re (blanket Xen)
MFC after: 2 weeks
sys/amd64/amd64/mp_machdep.c:
sys/i386/i386/mp_machdep.c:
- Make sure that are no MMU related IPIs pending on migration.
- Reset pending IPI_BITMAP on resume.
- Init vcpu_info on resume.
sys/amd64/include/intr_machdep.h:
sys/i386/include/intr_machdep.h:
sys/x86/acpica/acpi_wakeup.c:
sys/x86/x86/intr_machdep.c:
sys/x86/isa/atpic.c:
sys/x86/x86/io_apic.c:
sys/x86/x86/local_apic.c:
- Add a "suspend_cancelled" parameter to pic_resume(). For the
Xen PIC, restoration of interrupt services differs between
the aborted suspend and normal resume cases, so we must provide
this information.
sys/dev/acpica/acpi_timer.c:
sys/dev/xen/timer/timer.c:
sys/timetc.h:
- Don't swap out "suspend safe" timers across a suspend/resume
cycle. This includes the Xen PV and ACPI timers.
sys/dev/xen/control/control.c:
- Perform proper suspend/resume process for PVHVM:
- Suspend all APs before going into suspension, this allows us
to reset the vcpu_info on resume for each AP.
- Reset shared info page and callback on resume.
sys/dev/xen/timer/timer.c:
- Implement suspend/resume support for the PV timer. Since FreeBSD
doesn't perform a per-cpu resume of the timer, we need to call
smp_rendezvous in order to correctly resume the timer on each CPU.
sys/dev/xen/xenpci/xenpci.c:
- Don't reset the PCI interrupt on each suspend/resume.
sys/kern/subr_smp.c:
- When suspending a PVHVM domain make sure there are no MMU IPIs
in-flight, or we will get a lockup on resume due to the fact that
pending event channels are not carried over on migration.
- Implement a generic version of restart_cpus that can be used by
suspended and stopped cpus.
sys/x86/xen/hvm.c:
- Implement resume support for the hypercall page and shared info.
- Clear vcpu_info so it can be reset by APs when resuming from
suspension.
sys/dev/xen/xenpci/xenpci.c:
sys/x86/xen/hvm.c:
sys/x86/xen/xen_intr.c:
- Support UP kernel configurations.
sys/x86/xen/xen_intr.c:
- Properly rebind per-cpus VIRQs and IPIs on resume.
Properly round-trip the "operation code" for client requests.
sys/dev/xen/blkback/blkback.c:
In xbb_dispatch_dev() when processing a flush request,
correctly set bio->bio_caller1 to the request list (not
bare request) for the operation, as is expected by the
completion handler xbb_bio_done().
In xbb_get_resources(), initialize "operation" in the
driver's internal request object from the client's "ring
request", so it is correct when used to populate the reply
when this operation completes.
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
Initialize the request id for requests in xbb_get_resources()
instead of its previous location in xbb_dispatch_io(). This
guarantees that all request types (e.g. BLKIF_OP_FLUSH_DISKCACHE)
have the front-end specified id recorded.
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
value. Some hosts do not publish "extended" disk IDs via virtual-device in
an attempt to avoid confusing old blkfront drivers, and without this change
we failed to attach such disks.
In particular, this commit allows all 24 ephemeral disks on EC2 hs1.8xlarge
instances to be used, instead of only the first 15.
MFC after: 3 days
Use this new driver for both PV and HVM instances.
This driver requires a Xen hypervisor that supports vector callbacks,
VCPUOP hypercalls, and reports that it has a "safe PV clock".
New timer driver:
Submitted by: will
Sponsored by: Spectra Logic Corporation
PV port to new driver, and bug fixes:
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
sys/dev/xen/timer/timer.c:
- Register a PV timer device driver which (currently)
implements device_{identify,probe,attach} and stubs
device_detach. The detach routine requires functionality
not provided by timecounters(4). The suspend and resume
routines need additional work (due to Xen requiring that
the hypercalls be executed on the target VCPU), and aren't
needed for our purposes.
- Make sure there can only be one device instance of this
driver, and that it only registers one eventtimers(4) and
one timecounters(4) device interface. Make both interfaces
use PCPU data as needed.
- Match, with a few style cleanups & API differences, the
Xen versions of the "fetch time" functions.
- Document the magic scale_delta() better for the i386 version.
- When registering the event timer, bind a separate event
channel for the timer VIRQ to the device's event timer
interrupt handler for each active VCPU. Describe each
interrupt as "xen_et:c%d", so they can be identified per
CPU in "vmstat -i" or "show intrcnt" in KDB.
- When scheduling a timer into the hypervisor, try up to
60 times if the hypervisor rejects the time as being in
the past. In the common case, this retry shouldn't happen,
and if it does, it should only happen once. This is
because the event timer advertises a minimum period of
100usec, which is only less than the usual hypercall round
trip time about 1 out of every 100 tries. (Unlike other
similar drivers, this one actually checks whether the
hypervisor accepted the singleshot timer set hypercall.)
- Implement a RTC PV clock based on the hypervisor wallclock.
sys/conf/files:
- Add dev/xen/timer/timer.c if the kernel configuration
includes either the XEN or XENHVM options.
sys/conf/files.i386:
sys/i386/include/xen/xen_clock_util.h:
sys/i386/xen/clock.c:
sys/i386/xen/xen_clock_util.c:
sys/i386/xen/mp_machdep.c:
sys/i386/xen/xen_rtc.c:
- Remove previous PV timer used in i386 XEN PV kernels, the
new timer introduced in this change is used instead (so
we share the same code between PVHVM and PV).
MFC after: 2 weeks
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.
transparent layering and better fragmentation.
- Normalize functions that allocate memory to use kmem_*
- Those that allocate address space are named kva_*
- Those that operate on maps are named kmap_*
- Implement recursive allocation handling for kmem_arena in vmem.
Reviewed by: alc
Tested by: pho
Sponsored by: EMC / Isilon Storage Division
support cache flush and write barrier commands.
sys/dev/xen/blkfront/block.h:
Add per-command flag that specifies that the I/O queue must
be frozen after this command is dispatched. This is used
to implement "single-stepping".
Remove the unused per-command flag that indicates a polled
command.
Add block device instance flags to record backend features.
Add a block device instance flag to indicate the I/O queue
is frozen until all outstanding I/O completes.
Enhance the queue API to allow the number of elements in a
queue to be interrogated.
Prefer "inline" to "__inline".
sys/dev/xen/blkfront/blkfront.c:
Formalize queue freeze semantics by adding methods for both
global and command-associated queue freezing.
Provide mechanism to freeze the I/O queue until all outstanding
I/O completes. Use this to implement barrier semantics
(BIO_ORDERED) when the backend does not support
BLKIF_OP_WRITE_BARRIER commands.
Implement BIO_FLUSH as either a BLKIF_OP_FLUSH_DISKCACHE
command or a 0 byte write barrier. Currently, all publicly
available backends perform a diskcache flush when processing
barrier commands, and this frontend behavior matches what
is done in Linux.
Simplify code by using new queue length API.
Report backend features during device attach and via sysctl.
Submitted by: Roger Pau Monné
Submitted by: gibbs (Merge with new driver queue API, sysctl support)
only re-enable I/O when all reasons have cleared.
sys/dev/xen/blkfront/block.h:
In the block front driver softc, replace the boolean
XBDF_FROZEN flag with a count of commands and driver global
issues that freeze the I/O queue. So long xbd_qfrozen_cnt
is non-zero, I/O is halted.
Add flags to xbd_flags for tracking grant table entry and
free command resource shortages. Each of these classes can
increment xbd_qfrozen_cnt at most once.
Add a command flag (XBDCF_ASYNC_MAPPING) that is set whenever
the initial mapping attempt of a command fails with EINPROGRESS.
sys/dev/xen/blkfront/blkfront.c:
In xbd_queue_cb(), use new XBDCF_ASYNC_MAPPING flag to definitively
know if an async bus dmamap load has occurred.
Add xbd_freeze() and xbd_thaw() helper methods for managing
xbd_qfrozen_cnt and use them to implement all queue freezing logic.
Add missing "thaw" to restart I/O processing once grant references
become available.
Sponsored by: Spectra Logic Corporation
scheme for defining inline command queuing functions.
Prefer enums to #defines.
sys/dev/xen/blkfront/block.h
Replace inline function generation performed by the
XBDQ_COMMAND_QUEUE() macro with single instances of each
inline function (init, enqueue, dequeue, remove). This was
made possible by using queue indexes instead of bit flags
in the command structure, and passing the index enum as
an argument to the functions.
Improve panic/assert messages in the queue functions.
Combine queue data and stats into a single data structure
and declare an array of them instead of each queue individually.
Convert command flags, softc state, and softc flags to enums.
sys/dev/xen/blkfront/blkfront.c
Mechanical adjustments for new queue api.
Sponsored by: Spectra Logic Corporation
MFC after: 1 week
In netif_free(), call ifmedia_removeall() after ether_ifdetach()
so that bpf listeners are detached, any link state processing
is completed, and there is no chance for external reference to media
information.
Suggested by: yongari
MFC after: 1 week
Xen host side can handle after defragmentation.
This prevents the driver from throwing away too long TSO chains and
improves the performance on Amazon AWS instances with 10GigE virtual
interfaces to the normally expected throughput.
Submitted by: cperciva (earlier version)
Reviewed by: cperciva
Tested by: cperciva
MFC after: 1 week
Remove local, and incorrect, definition for the value of an invalid
grant reference.
Extract ring cleanup code into xbd_free_ring() function for
symetry with xbd_alloc_ring(). This process also eliminated
an initialized but unused variable.
Sponsored by: Spectra Logic Corporation
MFC after: 1 week
o Group functions by by their functionality.
o Remove superfluous declarations.
o Remove more unused (#ifdef'd out) code.
Sponsored by: Spectra Logic Corporation
o This driver is the "xbd" driver, not the "blkfront", "blkif", "xbf", or
"xb" driver. Use the "xbd_" naming conventions for all functions,
structures, and constants.
o The prevailing convention for structure fields in this driver is to
prefix them with an abreviation of the structure type. Update
"recently added" fields to match this style.
o Remove unused data structures.
o Remove superfluous casts.
o Make a pass over the whole driver and bring it closer to
style(9) conformance.
Sponsored by: Spectra Logic Corporation
MFC after: 1 week
dev/xen/netfront:
In netif_free(), properly stop the interface and drain any pending
timers prior to disconnecting from the backend device.
Remove all media and detach our interface object from the system
prior to deleting it.
PR: kern/176471
Submitted by: Roger Pau Monne <roger.pau@citrix.com>
Reviewed by: gibbs
MFC after: 1 week
__func__ and add some missing ones.
- Remove a stale comment.
- Remove unused NUM_ELEMENTS macro.
- Remove extra empty lines.
- Use DEVMETHOD_END.
- Use NULL rather than 0 for pointers.
MFC after: 3 days
- Replace incorrect function names in printf(9) strings with __func__.
- Make xctrl_shutdown_reasons table const.
- Use nitems() rather than rolling an own version.
- Use DEVMETHOD_END.
- Use NULL rather than 0 for pointers.
MFC after: 3 days
In particular, do not lock Giant conditionally when calling into the
filesystem module, remove the VFS_LOCK_GIANT() and related
macros. Stop handling buffers belonging to non-mpsafe filesystems.
The VFS_VERSION is bumped to indicate the interface change which does
not result in the interface signatures changes.
Conducted and reviewed by: attilio
Tested by: pho
a da(4) instance going away while GEOM is still probing it.
In this case, the GEOM disk class instance has been created by
disk_create(), and the taste of the disk is queued in the GEOM
event queue.
While that event is queued, the da(4) instance goes away. When the
open call comes into the da(4) driver, it dereferences the freed
(but non-NULL) peripheral pointer provided by GEOM, which results
in a panic.
The solution is to add a callback to the GEOM disk code that is
called when all of its resources are cleaned up. This is
implemented inside GEOM by adding an optional callback that is
called when all consumers have detached from a provider, and the
provider is about to be deleted.
scsi_cd.c,
scsi_da.c: In the register routine for the cd(4) and da(4)
routines, acquire a reference to the CAM peripheral
instance just before we call disk_create().
Use the new GEOM disk d_gone() callback to register
a callback (dadiskgonecb()/cddiskgonecb()) that
decrements the peripheral reference count once GEOM
has finished cleaning up its resources.
In the cd(4) driver, clean up open and close
behavior slightly. GEOM makes sure we only get one
open() and one close call, so there is no need to
set an open flag and decrement the reference count
if we are not the first open.
In the cd(4) driver, use cam_periph_release_locked()
in a couple of error scenarios to avoid extra mutex
calls.
geom.h: Add a new, optional, providergone callback that
is called when a provider is about to be deleted.
geom_disk.h: Add a new d_gone() callback to the GEOM disk
interface.
Bump the DISK_VERSION to version 2. This probably
should have been done after a couple of previous
changes, especially the addition of the d_getattr()
callback.
geom_disk.c: Add a providergone callback for the disk class,
g_disk_providergone(), that calls the user's
d_gone() callback if it exists.
Bump the DISK_VERSION to 2.
geom_subr.c: In g_destroy_provider(), call the providergone
callback if it has been provided.
In g_new_geomf(), propagate the class's
providergone callback to the new geom instance.
blkfront.c: Callers of disk_create() are supposed to pass in
DISK_VERSION, not an explicit disk API version
number. Update the blkfront driver to do that.
disk.9: Update the disk(9) man page to include information
on the new d_gone() callback, as well as the
previously added d_getattr() callback, d_descr
field, and HBA PCI ID fields.
MFC after: 5 days
