This adds a new kind of barrier, and reworks virtio and xen
to use it.
Plus some fixes here and there.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio barrier rework+fixes from Michael Tsirkin:
"This adds a new kind of barrier, and reworks virtio and xen to use it.
Plus some fixes here and there"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (44 commits)
checkpatch: add virt barriers
checkpatch: check for __smp outside barrier.h
checkpatch.pl: add missing memory barriers
virtio: make find_vqs() checkpatch.pl-friendly
virtio_balloon: fix race between migration and ballooning
virtio_balloon: fix race by fill and leak
s390: more efficient smp barriers
s390: use generic memory barriers
xen/events: use virt_xxx barriers
xen/io: use virt_xxx barriers
xenbus: use virt_xxx barriers
virtio_ring: use virt_store_mb
sh: move xchg_cmpxchg to a header by itself
sh: support 1 and 2 byte xchg
virtio_ring: update weak barriers to use virt_xxx
Revert "virtio_ring: Update weak barriers to use dma_wmb/rmb"
asm-generic: implement virt_xxx memory barriers
x86: define __smp_xxx
xtensa: define __smp_xxx
tile: define __smp_xxx
...
include/xen/interface/io/ring.h uses
full memory barriers to communicate with the other side.
For guests compiled with CONFIG_SMP, smp_wmb and smp_mb
would be sufficient, so mb() and wmb() here are only needed if
a non-SMP guest runs on an SMP host.
Switch to virt_xxx barriers which serve this exact purpose.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Rename the current XENPF_settime hypercall and related struct to
XENPF_settime32.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
The dom0_op hypercall has been renamed to platform_op since Xen 3.2,
which is ancient, and modern upstream Linux kernels cannot run as dom0
and it anymore anyway.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Using RING_GET_REQUEST() on a shared ring is easy to use incorrectly
(i.e., by not considering that the other end may alter the data in the
shared ring while it is being inspected). Safe usage of a request
generally requires taking a local copy.
Provide a RING_COPY_REQUEST() macro to use instead of
RING_GET_REQUEST() and an open-coded memcpy(). This takes care of
ensuring that the copy is done correctly regardless of any possible
compiler optimizations.
Use a volatile source to prevent the compiler from reordering or
omitting the copy.
This is part of XSA155.
CC: stable@vger.kernel.org
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
With the 64KB page granularity support on ARM64, a Linux page may be
split accross multiple grant.
Currently we have the helper gnttab_foreach_grant_in_grant to break a
Linux page based on an offset and a len, but it doesn't fit when we only
have a number of grants in hand.
Introduce a new helper which take an array of Linux page and a number of
grant and will figure out the address of each grant.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Linux may use a different page size than the size of grant. So make
clear that the order is actually in number of grant.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Many PV drivers contain the idiom:
pfn = page_to_gfn(...) /* Or similar */
gnttab_grant_foreign_access_ref
Replace it by a new helper. Note that when Linux is using a different
page granularity than Xen, the helper only gives access to the first 4KB
grant.
This is useful where drivers are allocating a full Linux page for each
grant.
Also include xen/interface/grant_table.h rather than xen/grant_table.h in
asm/page.h for x86 to fix a compilation issue [1]. Only the former is
useful in order to get the structure definition.
[1] Interdependency between asm/page.h and xen/grant_table.h which result
to page_mfn not being defined when necessary.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Currently, a grant is always based on the Xen page granularity (i.e
4KB). When Linux is using a different page granularity, a single page
will be split between multiple grants.
The new helpers will be in charge of splitting the Linux page into grants
and call a function given by the caller on each grant.
Also provide an helper to count the number of grants within a given
contiguous region.
Note that the x86/include/asm/xen/page.h is now including
xen/interface/grant_table.h rather than xen/grant_table.h. It's
necessary because xen/grant_table.h depends on asm/xen/page.h and will
break the compilation. Furthermore, only definition in
interface/grant_table.h is required.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
The Xen hypercall interface is always using 4K page granularity on ARM
and x86 architecture.
With the incoming support of 64K page granularity for ARM64 guest, it
won't be possible to re-use the Linux page definition in Xen drivers.
Introduce Xen page definition helpers based on the Linux page
definition. They have exactly the same name but prefixed with
XEN_/xen_ prefix.
Also modify xen_page_to_gfn to use new Xen page definition.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
alloc_xenballooned_pages() is used to get ballooned pages to back
foreign mappings etc. Instead of having to balloon out real pages,
use (if supported) hotplugged memory.
This makes more memory available to the guest and reduces
fragmentation in the p2m.
This is only enabled if the xen.balloon.hotplug_unpopulated sysctl is
set to 1. This sysctl defaults to 0 in case the udev rules to
automatically online hotplugged memory do not exist.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---
v3:
- Add xen.balloon.hotplug_unpopulated sysctl to enable use of hotplug
for unpopulated pages.
All users of alloc_xenballoon_pages() wanted low memory pages, so
remove the option for high memory.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The stats used for memory hotplug make no sense and are fiddled with
in odd ways. Remove them and introduce total_pages to track the total
number of pages (both populated and unpopulated) including those within
hotplugged regions (note that this includes not yet onlined pages).
This will be used in a subsequent commit (xen/balloon: only hotplug
additional memory if required) when deciding whether additional memory
needs to be hotplugged.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Commit 0bb599fd30 (xen: remove scratch
frames for ballooned pages and m2p override) removed the use of the
scratch page for ballooned out pages.
Remove some left over function definitions.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Currently there is a number of issues preventing PVHVM Xen guests from
doing successful kexec/kdump:
- Bound event channels.
- Registered vcpu_info.
- PIRQ/emuirq mappings.
- shared_info frame after XENMAPSPACE_shared_info operation.
- Active grant mappings.
Basically, newly booted kernel stumbles upon already set up Xen
interfaces and there is no way to reestablish them. In Xen-4.7 a new
feature called 'soft reset' is coming. A guest performing kexec/kdump
operation is supposed to call SCHEDOP_shutdown hypercall with
SHUTDOWN_soft_reset reason before jumping to new kernel. Hypervisor
(with some help from toolstack) will do full domain cleanup (but
keeping its memory and vCPU contexts intact) returning the guest to
the state it had when it was first booted and thus allowing it to
start over.
Doing SHUTDOWN_soft_reset on Xen hypervisors which don't support it is
probably OK as by default all unknown shutdown reasons cause domain
destroy with a message in toolstack log: 'Unknown shutdown reason code
5. Destroying domain.' which gives a clue to what the problem is and
eliminates false expectations.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
- Use the correct GFN/BFN terms more consistently.
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Merge tag 'for-linus-4.3-rc0b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen terminology fixes from David Vrabel:
"Use the correct GFN/BFN terms more consistently"
* tag 'for-linus-4.3-rc0b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/xenbus: Rename the variable xen_store_mfn to xen_store_gfn
xen/privcmd: Further s/MFN/GFN/ clean-up
hvc/xen: Further s/MFN/GFN clean-up
video/xen-fbfront: Further s/MFN/GFN clean-up
xen/tmem: Use xen_page_to_gfn rather than pfn_to_gfn
xen: Use correctly the Xen memory terminologies
arm/xen: implement correctly pfn_to_mfn
xen: Make clear that swiotlb and biomerge are dealing with DMA address
- Convert xen-blkfront to the multiqueue API
- [arm] Support binding event channels to different VCPUs.
- [x86] Support > 512 GiB in a PV guests (off by default as such a
guest cannot be migrated with the current toolstack).
- [x86] PMU support for PV dom0 (limited support for using perf with
Xen and other guests).
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Merge tag 'for-linus-4.3-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from David Vrabel:
"Xen features and fixes for 4.3:
- Convert xen-blkfront to the multiqueue API
- [arm] Support binding event channels to different VCPUs.
- [x86] Support > 512 GiB in a PV guests (off by default as such a
guest cannot be migrated with the current toolstack).
- [x86] PMU support for PV dom0 (limited support for using perf with
Xen and other guests)"
* tag 'for-linus-4.3-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (33 commits)
xen: switch extra memory accounting to use pfns
xen: limit memory to architectural maximum
xen: avoid another early crash of memory limited dom0
xen: avoid early crash of memory limited dom0
arm/xen: Remove helpers which are PV specific
xen/x86: Don't try to set PCE bit in CR4
xen/PMU: PMU emulation code
xen/PMU: Intercept PMU-related MSR and APIC accesses
xen/PMU: Describe vendor-specific PMU registers
xen/PMU: Initialization code for Xen PMU
xen/PMU: Sysfs interface for setting Xen PMU mode
xen: xensyms support
xen: remove no longer needed p2m.h
xen: allow more than 512 GB of RAM for 64 bit pv-domains
xen: move p2m list if conflicting with e820 map
xen: add explicit memblock_reserve() calls for special pages
mm: provide early_memremap_ro to establish read-only mapping
xen: check for initrd conflicting with e820 map
xen: check pre-allocated page tables for conflict with memory map
xen: check for kernel memory conflicting with memory layout
...
The privcmd code is mixing the usage of GFN and MFN within the same
functions which make the code difficult to understand when you only work
with auto-translated guests.
The privcmd driver is only dealing with GFN so replace all the mention
of MFN into GFN.
The ioctl structure used to map foreign change has been left unchanged
given that the userspace is using it. Nonetheless, add a comment to
explain the expected value within the "mfn" field.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Based on include/xen/mm.h [1], Linux is mistakenly using MFN when GFN
is meant, I suspect this is because the first support for Xen was for
PV. This resulted in some misimplementation of helpers on ARM and
confused developers about the expected behavior.
For instance, with pfn_to_mfn, we expect to get an MFN based on the name.
Although, if we look at the implementation on x86, it's returning a GFN.
For clarity and avoid new confusion, replace any reference to mfn with
gfn in any helpers used by PV drivers. The x86 code will still keep some
reference of pfn_to_mfn which may be used by all kind of guests
No changes as been made in the hypercall field, even
though they may be invalid, in order to keep the same as the defintion
in xen repo.
Note that page_to_mfn has been renamed to xen_page_to_gfn to avoid a
name to close to the KVM function gfn_to_page.
Take also the opportunity to simplify simple construction such
as pfn_to_mfn(page_to_pfn(page)) into xen_page_to_gfn. More complex clean up
will come in follow-up patches.
[1] http://xenbits.xen.org/gitweb/?p=xen.git;a=commitdiff;h=e758ed14f390342513405dd766e874934573e6cb
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Instead of using physical addresses for accounting of extra memory
areas available for ballooning switch to pfns as this is much less
error prone regarding partial pages.
Reported-by: Roger Pau Monné <roger.pau@citrix.com>
Tested-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Xen's PV network protocol includes messages to add/remove ethernet
multicast addresses to/from a filter list in the backend. This allows
the frontend to request the backend only forward multicast packets
which are of interest thus preventing unnecessary noise on the shared
ring.
The canonical netif header in git://xenbits.xen.org/xen.git specifies
the message format (two more XEN_NETIF_EXTRA_TYPEs) so the minimal
necessary changes have been pulled into include/xen/interface/io/netif.h.
To prevent the frontend from extending the multicast filter list
arbitrarily a limit (XEN_NETBK_MCAST_MAX) has been set to 64 entries.
This limit is not specified by the protocol and so may change in future.
If the limit is reached then the next XEN_NETIF_EXTRA_TYPE_MCAST_ADD
sent by the frontend will be failed with NETIF_RSP_ERROR.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Provide interfaces for recognizing accesses to PMU-related MSRs and
LVTPC APIC and process these accesses in Xen PMU code.
(The interrupt handler performs XENPMU_flush right away in the beginning
since no PMU emulation is available. It will be added with a later patch).
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Map shared data structure that will hold CPU registers, VPMU context,
V/PCPU IDs of the CPU interrupted by PMU interrupt. Hypervisor fills
this information in its handler and passes it to the guest for further
processing.
Set up PMU VIRQ.
Now that perf infrastructure will assume that PMU is available on a PV
guest we need to be careful and make sure that accesses via RDPMC
instruction don't cause fatal traps by the hypervisor. Provide a nop
RDPMC handler.
For the same reason avoid issuing a warning on a write to APIC's LVTPC.
Both of these will be made functional in later patches.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Set Xen's PMU mode via /sys/hypervisor/pmu/pmu_mode. Add XENPMU hypercall.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Export Xen symbols to dom0 via /proc/xen/xensyms (similar to
/proc/kallsyms).
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Use the newest headers from the xen tree to get some new structure
layouts.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Currently, the event channel rebind code is gated with the presence of
the vector callback.
The virtual interrupt controller on ARM has the concept of per-CPU
interrupt (PPI) which allow us to support per-VCPU event channel.
Therefore there is no need of vector callback for ARM.
Xen is already using a free PPI to notify the guest VCPU of an event.
Furthermore, the xen code initialization in Linux (see
arch/arm/xen/enlighten.c) is requesting correctly a per-CPU IRQ.
Introduce new helper xen_support_evtchn_rebind to allow architecture
decide whether rebind an event is support or not. It will always return
true on ARM and keep the same behavior on x86.
This is also allow us to drop the usage of xen_have_vector_callback
entirely in the ARM code.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
A non-percpu VIRQ (e.g., VIRQ_CONSOLE) may be freed on a different
VCPU than it is bound to. This can result in a race between
handle_percpu_irq() and removing the action in __free_irq() because
handle_percpu_irq() does not take desc->lock. The interrupt handler
sees a NULL action and oopses.
Only use the percpu chip/handler for per-CPU VIRQs (like VIRQ_TIMER).
# cat /proc/interrupts | grep virq
40: 87246 0 xen-percpu-virq timer0
44: 0 0 xen-percpu-virq debug0
47: 0 20995 xen-percpu-virq timer1
51: 0 0 xen-percpu-virq debug1
69: 0 0 xen-dyn-virq xen-pcpu
74: 0 0 xen-dyn-virq mce
75: 29 0 xen-dyn-virq hvc_console
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: <stable@vger.kernel.org>
Commit 77e32c89a7 ("clockevents: Manage device's state separately for
the core") decouples clockevent device's modes from states. With this
change when a Xen guest tries to resume, it won't be calling its
set_mode op which needs to be done on each VCPU in order to make the
hypervisor aware that we are in oneshot mode.
This happens because clockevents_tick_resume() (which is an intermediate
step of resuming ticks on a processor) doesn't call clockevents_set_state()
anymore and because during suspend clockevent devices on all VCPUs (except
for the one doing the suspend) are left in ONESHOT state. As result, during
resume the clockevents state machine will assume that device is already
where it should be and doesn't need to be updated.
To avoid this problem we should suspend ticks on all VCPUs during
suspend.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
There are several place using gnttab async unmap and wait for
completion, so move the common code to a function
gnttab_unmap_refs_sync().
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Originally Xen PV drivers only use single-page ring to pass along
information. This might limit the throughput between frontend and
backend.
The patch extends Xenbus driver to support multi-page ring, which in
general should improve throughput if ring is the bottleneck. Changes to
various frontend / backend to adapt to the new interface are also
included.
Affected Xen drivers:
* blkfront/back
* netfront/back
* pcifront/back
* scsifront/back
* vtpmfront
The interface is documented, as before, in xenbus_client.c.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: Bob Liu <bob.liu@oracle.com>
Cc: Konrad Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Make the IOCTL_PRIVCMD_MMAPBATCH_V2 (and older V1 version) map
multiple frames at a time rather than one at a time, despite the pages
being non-consecutive GFNs.
xen_remap_foreign_mfn_array() is added which maps an array of GFNs
(instead of a consecutive range of GFNs).
Since per-frame errors are returned in an array, privcmd must set the
MMAPBATCH_V1 error bits as part of the "report errors" phase, after
all the frames are mapped.
Migrate times are significantly improved (when using a PV toolstack
domain). For example, for an idle 12 GiB PV guest:
Before After
real 0m38.179s 0m26.868s
user 0m15.096s 0m13.652s
sys 0m28.988s 0m18.732s
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Auto-translated physmap guests (arm, arm64 and x86 PVHVM/PVH) map and
unmap foreign GFNs using the same method (updating the physmap).
Unify the two arm and x86 implementations into one commont one.
Note that on arm and arm64, the correct error code will be returned
(instead of always -EFAULT) and map/unmap failure warnings are no
longer printed. These changes are required if the foreign domain is
paging (-ENOENT failures are expected and must be propagated up to the
caller).
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
The header include/xen/interface/xen.h doesn't contain all definitions
from Xen's version of that header. Update it accordingly.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Hypercalls submitted by user space tools via the privcmd driver can
take a long time (potentially many 10s of seconds) if the hypercall
has many sub-operations.
A fully preemptible kernel may deschedule such as task in any upcall
called from a hypercall continuation.
However, in a kernel with voluntary or no preemption, hypercall
continuations in Xen allow event handlers to be run but the task
issuing the hypercall will not be descheduled until the hypercall is
complete and the ioctl returns to user space. These long running
tasks may also trigger the kernel's soft lockup detection.
Add xen_preemptible_hcall_begin() and xen_preemptible_hcall_end() to
bracket hypercalls that may be preempted. Use these in the privcmd
driver.
When returning from an upcall, call xen_maybe_preempt_hcall() which
adds a schedule point if if the current task was within a preemptible
hypercall.
Since _cond_resched() can move the task to a different CPU, clear and
set xen_in_preemptible_hcall around the call.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Pull networking updates from David Miller:
1) More iov_iter conversion work from Al Viro.
[ The "crypto: switch af_alg_make_sg() to iov_iter" commit was
wrong, and this pull actually adds an extra commit on top of the
branch I'm pulling to fix that up, so that the pre-merge state is
ok. - Linus ]
2) Various optimizations to the ipv4 forwarding information base trie
lookup implementation. From Alexander Duyck.
3) Remove sock_iocb altogether, from CHristoph Hellwig.
4) Allow congestion control algorithm selection via routing metrics.
From Daniel Borkmann.
5) Make ipv4 uncached route list per-cpu, from Eric Dumazet.
6) Handle rfs hash collisions more gracefully, also from Eric Dumazet.
7) Add xmit_more support to r8169, e1000, and e1000e drivers. From
Florian Westphal.
8) Transparent Ethernet Bridging support for GRO, from Jesse Gross.
9) Add BPF packet actions to packet scheduler, from Jiri Pirko.
10) Add support for uniqu flow IDs to openvswitch, from Joe Stringer.
11) New NetCP ethernet driver, from Muralidharan Karicheri and Wingman
Kwok.
12) More sanely handle out-of-window dupacks, which can result in
serious ACK storms. From Neal Cardwell.
13) Various rhashtable bug fixes and enhancements, from Herbert Xu,
Patrick McHardy, and Thomas Graf.
14) Support xmit_more in be2net, from Sathya Perla.
15) Group Policy extensions for vxlan, from Thomas Graf.
16) Remove Checksum Offload support for vxlan, from Tom Herbert.
17) Like ipv4, support lockless transmit over ipv6 UDP sockets. From
Vlad Yasevich.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1494+1 commits)
crypto: fix af_alg_make_sg() conversion to iov_iter
ipv4: Namespecify TCP PMTU mechanism
i40e: Fix for stats init function call in Rx setup
tcp: don't include Fast Open option in SYN-ACK on pure SYN-data
openvswitch: Only set TUNNEL_VXLAN_OPT if VXLAN-GBP metadata is set
ipv6: Make __ipv6_select_ident static
ipv6: Fix fragment id assignment on LE arches.
bridge: Fix inability to add non-vlan fdb entry
net: Mellanox: Delete unnecessary checks before the function call "vunmap"
cxgb4: Add support in cxgb4 to get expansion rom version via ethtool
ethtool: rename reserved1 memeber in ethtool_drvinfo for expansion ROM version
net: dsa: Remove redundant phy_attach()
IB/mlx4: Reset flow support for IB kernel ULPs
IB/mlx4: Always use the correct port for mirrored multicast attachments
net/bonding: Fix potential bad memory access during bonding events
tipc: remove tipc_snprintf
tipc: nl compat add noop and remove legacy nl framework
tipc: convert legacy nl stats show to nl compat
tipc: convert legacy nl net id get to nl compat
tipc: convert legacy nl net id set to nl compat
...
In an x86 PV guest, get_user_pages_fast() on a userspace address range
containing foreign mappings does not work correctly because the M2P
lookup of the MFN from a userspace PTE may return the wrong page.
Force get_user_pages_fast() to fail on such addresses by marking the PTEs
as special.
If Xen has XENFEAT_gnttab_map_avail_bits (available since at least
4.0), we can do so efficiently in the grant map hypercall. Otherwise,
it needs to be done afterwards. This is both inefficient and racy
(the mapping is visible to the task before we fixup the PTEs), but
will be fine for well-behaved applications that do not use the mapping
until after the mmap() system call returns.
Guests with XENFEAT_auto_translated_physmap (ARM and x86 HVM or PVH)
do not need this since get_user_pages() has always worked correctly
for them.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Introduce gnttab_unmap_refs_async() that can be used to safely unmap
pages that may be in use (ref count > 1). If the pages are in use the
unmap is deferred and retried later. This polling is not very clever
but it should be good enough if the cases where the delay is necessary
are rare.
The initial delay is 5 ms and is increased linearly on each subsequent
retry (to reduce load if the page is in use for a long time).
This is needed to allow block backends using grant mapping to safely
use network storage (block or filesystem based such as iSCSI or NFS).
The network storage driver may complete a block request whilst there
is a queued network packet retry (because the ack from the remote end
races with deciding to queue the retry). The pages for the retried
packet would be grant unmapped and the network driver (or hardware)
would access the unmapped page.
Signed-off-by: Jennifer Herbert <jennifer.herbert@citrix.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Use the "foreign" page flag to mark pages that have a grant map. Use
page->private to store information of the grant (the granting domain
and the grant reference).
Signed-off-by: Jennifer Herbert <jennifer.herbert@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Add gnttab_alloc_pages() and gnttab_free_pages() to allocate/free pages
suitable to for granted maps.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
When unmapping grants, instead of converting the kernel map ops to
unmap ops on the fly, pre-populate the set of unmap ops.
This allows the grant unmap for the kernel mappings to be trivially
batched in the future.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Conflicts:
drivers/net/xen-netfront.c
Minor overlapping changes in xen-netfront.c, mostly to do
with some buffer management changes alongside the split
of stats into TX and RX.
Signed-off-by: David S. Miller <davem@davemloft.net>
pfn_to_mfn(page_to_pfn(p)) is a common use case so add a generic
helper for it.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Using the native code here can't work properly, as the hypervisor would
normally have cleared the two reason bits by the time Dom0 gets to see
the NMI (if passed to it at all). There's a shared info field for this,
and there's an existing hook to use - just fit the two together. This
is particularly relevant so that NMIs intended to be handled by APEI /
GHES actually make it to the respective handler.
Note that the hook can (and should) be used irrespective of whether
being in Dom0, as accessing port 0x61 in a DomU would be even worse,
while the shared info field would just hold zero all the time. Note
further that hardware NMI handling for PVH doesn't currently work
anyway due to missing code in the hypervisor (but it is expected to
work the native rather than the PV way).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Introduce support for new hypercall GNTTABOP_cache_flush.
Use it to perform cache flashing on pages used for dma when necessary.
If GNTTABOP_cache_flush is supported by the hypervisor, we don't need to
bounce dma map operations that involve foreign grants and non-coherent
devices.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
The feature has been removed from Xen. Also Linux cannot use it on ARM32
without CONFIG_ARM_LPAE.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
The DEFINE_XENBUS_DRIVER() macro looks a bit weird and causes sparse
errors.
Replace the uses with standard structure definitions instead. This is
similar to pci and usb device registration.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
To be able to use an initially unmapped initrd with xen the following
header files must be synced to a newer version from the xen tree:
include/xen/interface/elfnote.h
include/xen/interface/xen.h
As the KEXEC and DUMPCORE related ELFNOTES are not relevant for the
kernel they are omitted from elfnote.h.
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
