gcc produces a "variably modified X at file scope" warning for
structures that use these size definitions. I think the definitions are
actually fine but can be rephrased with the __CONST_RING_SIZE macro more
cleanly anyway.
Reviewed by: markj, royger
Approved by: markj (mentor)
Sponsored by: Dell EMC Isilon
Differential revision: https://reviews.freebsd.org/D11417
is the same as the old MTU. In particular, on Amazon EC2 "T2" instances
without this change, the network interface is reinitialized every 30
minutes due to the MTU being (re)set when a new DHCP lease is obtained,
causing packets to be dropped, along with annoying syslog messages about
the link state changing.
As a side note, the behaviour this commit fixes was responsible for
exposing the locking problems fixed via r318523 and r318631.
Maintainers of other network interface drivers may wish to consider making
the corresponding change; the handling of SIOCSIFMTU does not seem to
exhibit a great deal of consistency between drivers.
MFC after: 1 week
Since netfront uses different locks for the RX and TX paths there's no need to
drop the RX lock before calling if_input.
Suggested by: jhb
Tested by: cperciva
Sponsored by: Citrix Systems R&D
MFC with: r318523
Make sure the RX ring lock is only released when the state of the ring is
consistent, or else concurrent calls to xn_rxeof might get an inconsistent ring
state and thus some packets might be processed twice.
Note that this is not very common, and could only happen when an interrupt is
delivered while in xn_ifinit.
Reported by: cperciva
Tested by: cperciva
MFC after: 1 week
Sponsored by: Citrix Systems R&D
Call disk_gone when the backend switches to the "Closing" state and blkfront
still has pending users. This allows the disk to be detached, and will call
into xbd_closing by itself when the geom layout cleanup has finished.
Reported by: bapt
Tested by: manu
Reviewed by: bapt
Sponsored by: Citrix Systems R&D
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D10772
Currently netfront is setting the flags of inbound packets with the checksum
not present (offloaded) to (CSUM_IP_CHECKED | CSUM_IP_VALID | CSUM_DATA_VALID |
CSUM_PSEUDO_HDR). According to the mbuf(9) man page this is not the correct
combination of flags, it should instead be (CSUM_DATA_VALID |
CSUM_PSEUDO_HDR).
Reviewed by: Wei Liu <wei.liu2@citrix.com>
MFC after: 2 weeks
Sponsored by: Citrix Systems R&D
Differential revision: https://reviews.freebsd.org/D9831
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
vm_map_lookup_done should only be called when the gntdev has finished poking at
the entry.
Reported by: alc
Reviewed by: alc
MFC after: 1 week
Sponsored by: Citrix Systems R&D
Convert PCIe hot plug support over to asking the firmware, if any, for
permission to use the HotPlug hardware. Implement pci_request_feature
for ACPI. All other host pci connections to allowing all valid feature
requests.
Sponsored by: Netflix
One test was inadvertently expecting a bug in the kernel's sscanf
implementation circa 2012. I don't know when that bug got fixed.
Reported by: royger
Reviewed by: royger
MFC after: 3 weeks
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D9766
Most of these are null pointer dereferences or missing error checks in the
unit tests. One is a missing error check in xnb_attach_failed. None can
cause real problems in running systems.
Reported by: Coverity
CIDs: 1092469 1092468 1092467 2092466 1092465 1092512 1092511 1092510
CIDs: 1092510 1092509 1092508 1092507
Reviewed by: royger
MFC after: 3 weeks
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D9234
The Xen grant table device treats the mmap offset parameter as an unsigned
type, and as so it must use the newly introduced UOFF_TO_IDX.
Sponsored by: Citrix Systems R&D
MFC after: 2 weeks
X-MFC-with: r313690
Note that the timer itself fully supports suspension, but due to the lack of
ordering during the resume process FreeBSD cannot guarantee that the timer is
resumed before any device attempts to use it.
Submitted by: Liuyingdong <liuyingdong@huawei.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D9639
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
feature_barrier and feature_flush variables. Otherwise, adjacent
variables on the stack, such as sector_size, may be overwritten, with
disastrous results.
Note that I did not see a good reason to revert the addition of zero
checks introduced in r310013. Better safe than sorry.
PR: 215209
Tested by: royger
MFC after: 3 days
non-zero sector size. Such a device would be a virtual disk of zero
bytes; clearly not useful, and not something we should try to attach.
As a fortuitous side effect, checking that these values are non-zero
here results in them not *becoming* zero later on the function. This
odd behaviour began with r309124 (clang 3.9.0) but is challenging to
debug; making any changes to this function whatsoever seems to affect
the llvm optimizer behaviour enough to make the unexpected zeroing of
the sector_size variable cease.
PR: 215209
Security: The potential for variables to unexpectedly become zero
has worrying consequences for security in general, but
not so much in this particular context.
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
Simplify the logic involved in changing the nic features on the fly, and
only reset the frontend when really needed (when changing RX features). Also
don't return from the ioctl until the interface has been properly
reconfigured.
While there, make sure XN_CSUM_FEATURES is used consistently.
Reported by: julian
MFC after: 5 days
X-MFC-with: r303488
Sponsored by: Citrix Systems R&D
In certain circumstances xn_txq_mq_start might be called with num_queues ==
0 during the resume phase after a migration, which can trigger a KASSERT.
Fix this by making sure the carrier is on before trying to transmit, or else
return that the queues are full.
Just as a note, I haven't been able to reproduce this crash on my test
systems, but I still think it's possible and worth fixing.
Reported by: Karl Pielorz <kpielorz_lst@tdx.co.uk>
Sponsored by: Citrix Systems R&D
MFC after: 5 days
Reviewed by: Wei Liu <wei.liu2@citrix.com>
Differential revision: https://reviews.freebsd.org/D7349
r298930 removed the inittodr call, but it seems like this prevents
"calcru: runtime went backwards ..." messages from occasionally appearing
when resuming from migration.
Reported by: Karl Pielorz <kpielorz@tdx.co.uk>
Sponsored by: Citrix Systems R&D
A couple of mostly cosmetic fixes for the final initialization of netfront:
- Switch to "connected" state before starting to kick the rings.
- Correctly use "rxq" in the initialization loop (previously rxq was not
updated in the loop, and netfront would kick np->rxq[N] several times).
- Declare and define xn_connect as static, it's not used outside of this
file.
Reviewed by: Wei Liu <wei.liu2@citrix.com>
Sponsored by: Citrix Systems R&D
Differential revision: https://reviews.freebsd.org/D6657
The current error path in case of failure during attach/initialization is
not correct and leaves blkback in a stuck state. This is due to blkback
waiting for blkfront to switch to state XenbusStateClosed, but if blkfront
never attached (because the guest is not even started) it cannot possibly
make it to that state.
Instead just wait for the frontend to be in a state different than
XenbusStateConnected in order to proceed with the shutdown. Also, it is
wrong to call xbb_detach directly because it destroys the lock which can
still be used by xbb_frontend_changed.
Sponsored by: Citrix Systems R&D
Hotplug scripts are needed in order to use fancy disk configurations in xl,
like iSCSI disks. The job of hotplug scripts is to locally attach the disk
and present it to blkback as a block device or a regular file.
This change introduces a new xenstore node in the blkback hierarchy, called
"physical-device-path". This is a straigh replacement for the "params" node,
which was used before.
Hotplug scripts will need to read the "params" node, perform whatever
actions are necessary and then write the "physical-device-path" node. The
hotplug script is also in charge of detaching the disk once the domain has
been shutdown.
Sponsored by: Citrix Systems R&D
The PV backend will only pick the new options when the interface is detached
and reattached again, so perform a full reset when changing options. This is
very fast, and should not be noticeable by the user.
Reviewed by: Wei Liu <wei.liu2@citrix.com>
Sponsored by: Citrix Systems R&D
Differential revision: https://reviews.freebsd.org/D6658
Just calling gnttab_end_foreign_access_ref doesn't free the references,
instead call gnttab_end_foreign_access with a NULL page argument in order to
have the grant references freed. The code that maps the ring
(xenbus_map_ring) already uses gnttab_grant_foreign_access which takes care
of allocating a grant reference.
Reviewed by: Wei Liu <wei.liu2@citrix.com>
Sponsored by: Citrix Systems R&D
Differential revision: https://reviews.freebsd.org/D6608
This patch fixes two issues seen on hot-unplug. The first one is a panic
caused by calling ether_ifdetach after freeing the internal netfront queue
structures. ether_ifdetach will call xn_qflush, and this needs to be done
before freeing the queues. This prevents the following panic:
Fatal trap 9: general protection fault while in kernel mode
cpuid = 2; apic id = 04
instruction pointer = 0x20:0xffffffff80b1687f
stack pointer = 0x28:0xfffffe009239e770
frame pointer = 0x28:0xfffffe009239e780
code segment = base 0x0, limit 0xfffff, type 0x1b
= DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags = interrupt enabled, resume, IOPL = 0
current process = 0 (thread taskq)
[ thread pid 0 tid 100015 ]
Stopped at strlen+0x1f: movq (%rcx),%rax
db> bt
Tracing pid 0 tid 100015 td 0xfffff800038a6000
strlen() at strlen+0x1f/frame 0xfffffe009239e780
kvprintf() at kvprintf+0xfa0/frame 0xfffffe009239e890
vsnprintf() at vsnprintf+0x31/frame 0xfffffe009239e8b0
kassert_panic() at kassert_panic+0x5a/frame 0xfffffe009239e920
__mtx_lock_flags() at __mtx_lock_flags+0x164/frame 0xfffffe009239e970
xn_qflush() at xn_qflush+0x59/frame 0xfffffe009239e9b0
if_detach() at if_detach+0x17e/frame 0xfffffe009239ea10
netif_free() at netif_free+0x97/frame 0xfffffe009239ea30
netfront_detach() at netfront_detach+0x11/frame 0xfffffe009239ea40
[...]
Another panic can be triggered by hot-plugging a NIC:
Fatal trap 18: integer divide fault while in kernel mode
cpuid = 0; apic id = 00
instruction pointer = 0x20:0xffffffff80902203
stack pointer = 0x28:0xfffffe00508d3660
frame pointer = 0x28:0xfffffe00508d36a0
code segment = base 0x0, limit 0xfffff, type 0x1b
= DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags = interrupt enabled, resume, IOPL = 0
current process = 2960 (ifconfig)
[ thread pid 2960 tid 100088 ]
Stopped at xn_txq_mq_start+0x33: divl %esi,%eax
db> bt
Tracing pid 2960 tid 100088 td 0xfffff8000850aa00
xn_txq_mq_start() at xn_txq_mq_start+0x33/frame 0xfffffe00508d36a0
ether_output() at ether_output+0x570/frame 0xfffffe00508d3720
arprequest() at arprequest+0x433/frame 0xfffffe00508d3820
arp_ifinit() at arp_ifinit+0x49/frame 0xfffffe00508d3850
xn_ioctl() at xn_ioctl+0x1a2/frame 0xfffffe00508d3890
in_control() at in_control+0x882/frame 0xfffffe00508d3910
ifioctl() at ifioctl+0xda1/frame 0xfffffe00508d39a0
kern_ioctl() at kern_ioctl+0x246/frame 0xfffffe00508d3a00
sys_ioctl() at sys_ioctl+0x171/frame 0xfffffe00508d3ae0
amd64_syscall() at amd64_syscall+0x2db/frame 0xfffffe00508d3bf0
Xfast_syscall() at Xfast_syscall+0xfb/frame 0xfffffe00508d3bf0
--- syscall (54, FreeBSD ELF64, sys_ioctl), rip = 0x8011e185a, rsp =
0x7fffffffe478, rbp = 0x7fffffffe4c0 ---
This is caused by marking the driver as active before it's fully
initialized, and thus calling xn_txq_mq_start with num_queues set to 0.
Reviewed by: Wei Liu <wei.liu2@citrix.com>
Sponsored by: Citrix Systems R&D
Differential revision: https://reviews.freebsd.org/D6646
In order to use custom taskqueues we would have to mask the interrupt, which
is basically what is already done for an interrupt handler, or else we risk
loosing interrupts. This switches netfront to the same interrupt handling
that was done before multiqueue support was added.
Reviewed by: Wei Liu <wei.liu2@citrix.com>
Sponsored by: Citrix Systems R&D
This is based on Linux commit 1f3c2eba1e2d866ef99bb9b10ade4096e3d7607c from
David Vrabel:
A full Rx ring only requires 1 MiB of memory. This is not enough memory
that it is useful to dynamically scale the number of Rx requests in the ring
based on traffic rates, because:
a) Even the full 1 MiB is a tiny fraction of a typically modern Linux
VM (for example, the AWS micro instance still has 1 GiB of memory).
b) Netfront would have used up to 1 MiB already even with moderate
data rates (there was no adjustment of target based on memory
pressure).
c) Small VMs are going to typically have one VCPU and hence only one
queue.
Keeping the ring full of Rx requests handles bursty traffic better than
trying to converge on an optimal number of requests to keep filled.
Reviewed by: Wei Liu <wei.liu2@citrix.com>
Sponsored by: Citrix Systems R&D
Currently FreeBSD is not properly fetching the TSO information from the Xen
PV ring, and thus the received packets didn't have all the necessary
information, like the segment size or even the TSO flag set.
Sponsored by: Citrix Systems R&D
Currently, Application Processors (non-boot CPUs) are started by
MD code at SI_SUB_CPU, but they are kept waiting in a "pen" until
SI_SUB_SMP at which point they are released to run kernel threads.
SI_SUB_SMP is one of the last SYSINIT levels, so APs don't enter
the scheduler and start running threads until fairly late in the
boot.
This change moves SI_SUB_SMP up to just before software interrupt
threads are created allowing the APs to start executing kernel
threads much sooner (before any devices are probed). This allows
several initialization routines that need to perform initialization
on all CPUs to now perform that initialization in one step rather
than having to defer the AP initialization to a second SYSINIT run
at SI_SUB_SMP. It also permits all CPUs to be available for
handling interrupts before any devices are probed.
This last feature fixes a problem on with interrupt vector exhaustion.
Specifically, in the old model all device interrupts were routed
onto the boot CPU during boot. Later after the APs were released at
SI_SUB_SMP, interrupts were redistributed across all CPUs.
However, several drivers for multiqueue hardware allocate N interrupts
per CPU in the system. In a system with many CPUs, just a few drivers
doing this could exhaust the available pool of interrupt vectors on
the boot CPU as each driver was allocating N * mp_ncpu vectors on the
boot CPU. Now, drivers will allocate interrupts on their desired CPUs
during boot meaning that only N interrupts are allocated from the boot
CPU instead of N * mp_ncpu.
Some other bits of code can also be simplified as smp_started is
now true much earlier and will now always be true for these bits of
code. This removes the need to treat the single-CPU boot environment
as a special case.
As a transition aid, the new behavior is available under a new kernel
option (EARLY_AP_STARTUP). This will allow the option to be turned off
if need be during initial testing. I plan to enable this on x86 by
default in a followup commit in the next few days and to have all
platforms moved over before 11.0. Once the transition is complete,
the option will be removed along with the !EARLY_AP_STARTUP code.
These changes have only been tested on x86. Other platform maintainers
are encouraged to port their architectures over as well. The main
things to check for are any uses of smp_started in MD code that can be
simplified and SI_SUB_SMP SYSINITs in MD code that can be removed in
the EARLY_AP_STARTUP case (e.g. the interrupt shuffling).
PR: kern/199321
Reviewed by: markj, gnn, kib
Sponsored by: Netflix
Current netfront code relies on xs_scanf returning a value < 0 on error,
which is not right, xs_scanf returns a positive value on error.
MFC after: 3 days
Tested by: Stephen Jones <StephenJo@LivingComputerMuseum.org>
Sponsored by: Citrix Systems R&D
This is quite harmless on HEAD, but it's worse on stable/10 where
lapic_ipi_vectored is the local APIC native IPI implementation. On
stable/10 cpu_ops.ipi_vectored should be used instead.
MFC after: 5 days
Sponsored by: Citrix Systems R&D
The size field in the XENMEM_add_to_physmap_range is an uint16_t, and the
privcmd driver was doing an implicit truncation of an int into an uint16_t
when filling the hypercall parameters.
Fix this by adding a loop and making sure privcmd splits ioctl request into
2^16 chunks when issuing the hypercalls.
Reported and tested by: Marcin Cieslak <saper@saper.info>
Sponsored by: Citrix Systems R&D
Two new functions are provided, bit_ffs_at() and bit_ffc_at(), which allow
for efficient searching of set or cleared bits starting from any bit offset
within the bit string.
Performance is improved by operating on longs instead of bytes and using
ffsl() for searches within a long. ffsl() is a compiler builtin in both
clang and gcc for most architectures, converting what was a brute force
while loop search into a couple of instructions.
All of the bitstring(3) API continues to be contained in the header file.
Some of the functions are large enough that perhaps they should be uninlined
and moved to a library, but that is beyond the scope of this commit.
sys/sys/bitstring.h:
Convert the majority of the existing bit string implementation from
macros to inline functions.
Properly protect the implementation from inadvertant macro expansion
when included in a user's program by prefixing all private
macros/functions and local variables with '_'.
Add bit_ffs_at() and bit_ffc_at(). Implement bit_ffs() and
bit_ffc() in terms of their "at" counterparts.
Provide a kernel implementation of bit_alloc(), making the full API
usable in the kernel.
Improve code documenation.
share/man/man3/bitstring.3:
Add pre-exisiting API bit_ffc() to the synopsis.
Document new APIs.
Document the initialization state of the bit strings
allocated/declared by bit_alloc() and bit_decl().
Correct documentation for bitstr_size(). The original code comments
indicate the size is in bytes, not "elements of bitstr_t". The new
implementation follows this lead. Only hastd assumed "elements"
rather than bytes and it has been corrected.
etc/mtree/BSD.tests.dist:
tests/sys/Makefile:
tests/sys/sys/Makefile:
tests/sys/sys/bitstring.c:
Add tests for all existing and new functionality.
include/bitstring.h
Include all headers needed by sys/bitstring.h
lib/libbluetooth/bluetooth.h:
usr.sbin/bluetooth/hccontrol/le.c:
Include bitstring.h instead of sys/bitstring.h.
sbin/hastd/activemap.c:
Correct usage of bitstr_size().
sys/dev/xen/blkback/blkback.c
Use new bit_alloc.
sys/kern/subr_unit.c:
Remove hard-coded assumption that sizeof(bitstr_t) is 1. Get rid of
unrb.busy, which caches the number of bits set in unrb.map. When
INVARIANTS are disabled, nothing needs to know that information.
callapse_unr can be adapted to use bit_ffs and bit_ffc instead.
Eliminating unrb.busy saves memory, simplifies the code, and
provides a slight speedup when INVARIANTS are disabled.
sys/net/flowtable.c:
Use the new kernel implementation of bit-alloc, instead of hacking
the old libc-dependent macro.
sys/sys/param.h
Update __FreeBSD_version to indicate availability of new API
Submitted by: gibbs, asomers
Reviewed by: gibbs, ngie
MFC after: 4 weeks
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D6004
The Xen PV clock has a resolution of 1ns, so set the resolution to the
highest one that FreeBSD supports, which is 1us.
MFC after: 2 weeks
Sponsored by: Citrix Systems R&D
Implement several small improvements to the suspend/resume Xen sequence:
- Call the power_suspend_early event before stopping all processes.
- Stop all processes. This was done implicitly previously by putting all
the CPUs in a known IPI handler.
- Warm up the timecounter.
- Re-initialize the time of day register.
Sponsored by: Citrix Systems R&D
The current resolution of the Xen PV clock is too high, which causes an
adjustment of 5s to be applied to it. Reduce the resolution to be the same
as the RTC plus one, so it's always selected as the best source when
available on x86.
Also don't reset the clock on resume, it's pointless and discards any
previous adjustments.
Sponsoted by: Citrix Systems R&D
Dom0 should be able to set the host time. This is implemented by first
writing to the RTC (as would be done on bare metal), and then using the
XENPF_settime64 hypercall in order to force Xen to update the wallclock
shared page of all domains.
Sponsored by: Citrix Systems R&D
With the removal of the usage of the VCPU_SSHOTTMR_future flag, now
all errors from xentimer_vcpu_start_timer should be considered fatal, and
the loop is no longer needed since in case of setting the timer in the past
we will get an event interrupt right away (instead of returning ETIME).
Sponsored by: Citrix Systems R&D
MFC after : 2 weeks
On slow platforms with unreliable TSC, such as QEMU emulated machines,
it is possible for the FreeBSD kernel to request the next event in the
past. In that case, in the current implementation of
xentimer_vcpu_start_timer, we simply return -ETIME. To be precise Xen
returns -ETIME and we pass it on. As a consequence we need to loop
around to function to make sure that the timer is properly set.
Instead it is better to always ask the hypervisor for a timer event,
even if the timeout is past. To do that, remove the VCPU_SSHOTTMR_future
flag.
Submitted by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed by: royger
MFC after: 2 weeks
Previously, the ACPI PCI bus driver did a single pass over the devices in
the namespace that were a child of a given PCI bus to associate the
PCI bus-enumerated device_t devices with the corresponding ACPI handles.
However, this meant that handles were only established at runtime for devices
found during the initial PCI bus scan.
PCI_IOV adds devices that show up after the initial PCI bus scan, and coming
changes to add a bus rescan can also add devices after the initial scan.
This change adds a pci_child_added() callback to the ACPI PCI bus that walks
the namespace to find the ACPI handle for each device that is added. Using
a callback means that the handle is correctly set for any device no matter
how it is added (initial scan, IOV, or a bus rescan).
And factor out tcp_lro_rx_done, which deduplicates the same logic with
netinet/tcp_lro.c
Reviewed by: gallatin (1st version), hps, zbb, np, Dexuan Cui <decui microsoft com>
Sponsored by: Microsoft OSTC
Differential Revision: https://reviews.freebsd.org/D5725
taskqueue_enqueue() was changed to support both fast and non-fast
taskqueues 10 years ago in r154167. It has been a compat shim ever
since. It's time for the compat shim to go.
Submitted by: Howard Su <howard0su@gmail.com>
Reviewed by: sephe
Differential Revision: https://reviews.freebsd.org/D5131
The m_ext.ext_cnt pointer becomes a union. It can now hold the refcount
value itself. To tell that m_ext.ext_flags flag EXT_FLAG_EMBREF is used.
The first mbuf to attach a cluster stores the refcount. The further mbufs
to reference the cluster point at refcount in the first mbuf. The first
mbuf is freed only when the last reference is freed.
The benefit over refcounts stored in separate slabs is that now refcounts
of different, unrelated mbufs do not share a cache line.
For EXT_EXTREF mbufs the zone_ext_refcnt is no longer needed, and m_extadd()
becomes void, making widely used M_EXTADD macro safe.
For EXT_SFBUF mbufs the sf_ext_ref() is removed, which was an optimization
exactly against the cache aliasing problem with regular refcounting.
Discussed with: rrs, rwatson, gnn, hiren, sbruno, np
Reviewed by: rrs
Differential Revision: https://reviews.freebsd.org/D5396
Sponsored by: Netflix
xn_ifp is allocated in create_netdev with if_alloc(IFT_ETHER).
According to the current arrangement it can't be NULL.
Coverity ID: 1349805
Submitted by: Wei Liu <wei.liu2@citrix.com>
Reviewed by: royger
Sponsored by: Citrix Systems R&D
Differential revision: https://reviews.freebsd.org/D5252
The variable error is assigned to 0 before entering the switch.
Assigning error to 0 before break pointless rewrites the real error
value that should be returned.
Coverity ID: 1304974
Submitted by: Wei Liu <wei.liu2@citrix.com>
Reviewed by: royger
Sponsored by: Citrix Systems R&D
Differential revision: https://reviews.freebsd.org/D5250
Add support for multiple TX and RX queue pairs. The default number of queues
is set to 4, but can be easily changed from the sysctl node hw.xn.num_queues.
Also heavily refactor netfront driver: break out a bunch of helper
functions and different structures. Use threads to handle TX and RX.
Remove some dead code and fix quite a few bugs as I go along.
Submitted by: Wei Liu <wei.liu2@citrix.com>
Reviewed by: royger
Sponsored by: Citrix Systems R&D
Relnotes: Yes
Differential Revision: https://reviews.freebsd.org/D4193
by busdma to the blkfront driver must be an integer number of sectors,
and must be aligned in memory on a "sector" boundary.
Having these assertions yesterday would have made finding the bug fixed
in r293698 somewhat easier.
Current Xen resume code clears all pending bitmap IPIs on resume, which is
not correct. Instead re-inject bitmap IPI vectors on resume to all CPUs in
order to acknowledge any pending bitmap IPIs.
Sponsored by: Citrix Systems R&D
MFC after: 2 weeks
Using unmapped IO is really beneficial when running inside of a VM,
since it avoids IPIs to other vCPUs in order to invalidate the
mappings.
This patch adds unmapped IO support to blkfront. The following tests
results have been obtained when running on a Xen host without HAP:
PVHVM
3165.84 real 6354.17 user 4483.32 sys
PVHVM with unmapped IO
2099.46 real 4624.52 user 2967.38 sys
This is because when running using shadow page tables TLB flushes and
range invalidations are much more expensive, so using unmapped IO
provides a very important performance boost.
Sponsored by: Citrix Systems R&D
MFC after: 2 weeks
X-MFC-with: r290610
dev/xen/blkfront/blkfront.c:
- Add and announce support for unmapped IO.
The new load_ma implementation can cause dereferences when used with
certain drivers, back it out until the reason is found:
Fatal trap 12: page fault while in kernel mode
cpuid = 11; apic id = 03
fault virtual address = 0x30
fault code = supervisor read data, page not present
instruction pointer = 0x20:0xffffffff808a2d22
stack pointer = 0x28:0xfffffe07cc737710
frame pointer = 0x28:0xfffffe07cc737790
code segment = base 0x0, limit 0xfffff, type 0x1b
= DPL 0, pres 1, long 1, def32 0, gran 1
processor eflags = interrupt enabled, resume, IOPL = 0
current process = 13 (g_down)
trap number = 12
panic: page fault
cpuid = 11
KDB: stack backtrace:
#0 0xffffffff80641647 at kdb_backtrace+0x67
#1 0xffffffff80606762 at vpanic+0x182
#2 0xffffffff806067e3 at panic+0x43
#3 0xffffffff8084eef1 at trap_fatal+0x351
#4 0xffffffff8084f0e4 at trap_pfault+0x1e4
#5 0xffffffff8084e82f at trap+0x4bf
#6 0xffffffff80830d57 at calltrap+0x8
#7 0xffffffff8063beab at _bus_dmamap_load_ccb+0x1fb
#8 0xffffffff8063bc51 at bus_dmamap_load_ccb+0x91
#9 0xffffffff8042dcad at ata_dmaload+0x11d
#10 0xffffffff8042df7e at ata_begin_transaction+0x7e
#11 0xffffffff8042c18e at ataaction+0x9ce
#12 0xffffffff802a220f at xpt_run_devq+0x5bf
#13 0xffffffff802a17ad at xpt_action_default+0x94d
#14 0xffffffff802c0024 at adastart+0x8b4
#15 0xffffffff802a2e93 at xpt_run_allocq+0x193
#16 0xffffffff802c0735 at adastrategy+0xf5
#17 0xffffffff80554206 at g_disk_start+0x426
Uptime: 2m29s
Using unmapped IO is really beneficial when running inside of a VM,
since it avoids IPIs to other vCPUs in order to invalidate the
mappings.
This patch adds unmapped IO support to blkfront. The following tests
results have been obtained when running on a Xen host without HAP:
PVHVM
3165.84 real 6354.17 user 4483.32 sys
PVHVM with unmapped IO
2099.46 real 4624.52 user 2967.38 sys
This is because when running using shadow page tables TLB flushes and
range invalidations are much more expensive, so using unmapped IO
provides a very important performance boost.
Sponsored by: Citrix Systems R&D
MFC after: 2 weeks
X-MFC-with: r289834
r289587 broke LINT-NOIP kernels because the lro and queued local variables
are defined but not used. Add preprocessor guards around them.
Reported by: emaste
Sponsored by: Citrix Systems R&D
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 failure path for allocating rx grant refs should not try to free tx
grant refs because tx grant refs were allocated after that. Also fix the
error path for xen_net_read_mac.
Submitted by: Wei Liu <wei.liu2@citrix.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D3891
Sponsored by: Citrix Systems R&D
This is redundant because ether_ifattach will set that field.
Submitted by: Wei Liu <wei.liu2@citrix.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D3918
Sponsored by: Citrix Systems R&D
We're way beyond FreeBSD 7 at this point.
Submitted by: Wei Liu <wei.liu2@citrix.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D3892
Sponsored by: Citrix Systems R&D
Multiqueue feature will make the number of queues dynamic, so XN_LOCK_INIT
won't be that useful. Remove the macro and call mtx_init directly.
XN_LOCK_DESTROY is just dead code.
Submitted by: Wei Liu <wei.liu2@citrix.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D3890
Sponsored by: Citrix Systems R&D
Rename it with netfront_ prefix and purge a bunch of unused fields.
Submitted by: Wei Liu <wei.liu2@citrix.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D3889
Sponsored by: Citrix Systems R&D
Currently neither Linux nor FreeBSD netback supports page flipping. NetBSD
still supports that. It is not sure how many people actually use page
flipping, but page flipping is supposed to be slower than copying nowadays.
It will also shatter frontend / backend address space.
Overall this feature is more of a burden than a benefit.
Submitted by: Wei Liu <wei.liu2@citrix.com>
Reviewed by: royger
Differential Revision: https://reviews.freebsd.org/D3888
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
When the system has more than a single PCI domain, the bus numbers
are not unique, thus they cannot be used for "pci" device numbering.
Change bus numbers to -1 (i.e. to-be-determined automatically)
wherever the code did not care about domains.
Reviewed by: jhb
Obtained from: Semihalf
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D3406
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
use vtophys() directly instead of vtomach() and retire the no-longer-used
headers <machine/xenfunc.h> and <machine/xenvar.h>.
Reported by: bde (stale bits in <machine/xenfunc.h>)
Reviewed by: royger (earlier version)
Differential Revision: https://reviews.freebsd.org/D3266
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
Previously several places were doing it on its own, partially
incorrectly (e.g. without the filedesc locked) or even actively harmful
by populating jdir or assigning rootvnode without vrefing it.
Reviewed by: kib
Try to preserve the xn configuration when migrating. This is not always
possible since the backend might not have the same set of options
available, in which case we will try to preserve as many as possible.
MFC after: 2 weeks
PR: 183139
Reported by: mcdouga9@egr.msu.edu
Sponsored by: Citrix Systems R&D
xbd_initialize to xbd_connect. Both of these initialization steps need
to know what the maximum possible I/O size will be, and when we gain
support for indirect segment I/Os we won't know that value until we
reach xbd_connect. Since none of this data is used before xbd_connect
completes, moving the initialization is harmless.
This commit should not result in any functional changes.
into blkif segments, and moving it into a new function. This will be used
by upcoming support for indirect-segment blkif requests.
This commit should not result in any functional changes.
* nsegs must be at most BLKIF_MAX_SEGMENTS_PER_REQUEST (since we specify
that limit to bus_dma_tag_create), so KASSERT that rather than silently
adjusting the request.
* block_segs is now a synonym for nsegs, so garbage collect that variable.
* nsegs is never read during or after the while loop, so remove the dead
decrement from the loop.
These were all left behind from the pre-r284296 support for a "segment
block" extension.
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
years for head. However, it is continuously misused as the mpsafe argument
for callout_init(9). Deprecate the flag and clean up callout_init() calls
to make them more consistent.
Differential Revision: https://reviews.freebsd.org/D2613
Reviewed by: jhb
MFC after: 2 weeks
Netfront has to wait for the backend to switch to state XenbusStateConnected
before sending the ARP request, or else the backend might not be connected
and thus the packet will be lost.
Sponsored by: Citrix Systems R&D
MFC after: 1 week
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>
remains. Xen is planning to phase out support for PV upstream since it
is harder to maintain and has more overhead. Modern x86 CPUs include
virtualization extensions that support HVM guests instead of PV guests.
In addition, the PV code was i386 only and not as well maintained recently
as the HVM code.
- Remove the i386-only NATIVE option that was used to disable certain
components for PV kernels. These components are now standard as they
are on amd64.
- Remove !XENHVM bits from PV drivers.
- Remove various shims required for XEN (e.g. PT_UPDATES_FLUSH, LOAD_CR3,
etc.)
- Remove duplicate copy of <xen/features.h>.
- Remove unused, i386-only xenstored.h.
Differential Revision: https://reviews.freebsd.org/D2362
Reviewed by: royger
Tested by: royger (i386/amd64 HVM domU and amd64 PVH dom0)
Relnotes: yes
Handle the VIRQ_DEBUG signal and print a stack trace of each vCPU on the Xen
console. This is only used for debug purposes and is triggered by the
administrator of the Xen host.
Sponsored by: Citrix Systems R&D
MFC after: 1 week