The netback source module has become very large and somewhat confusing.
This patch simply moves all code related to the backend to frontend (i.e
guest side rx) data-path into a separate rx source module.
This patch contains no functional change, it is code movement and
minimal changes to avoid patch style-check issues.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of open coding it use the threaded irq mechanism in
xen-netback.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
My recent patch to include/xen/interface/io/netif.h defines a new extra
info type that can be used to pass hash values between backend and guest
frontend.
This patch adds code to xen-netback to use the value in a hash extra
info fragment passed from the guest frontend in a transmit-side
(i.e. netback receive side) packet to set the skb hash accordingly.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
My recent patch to include/xen/interface/io/netif.h defines a new extra
info type that can be used to pass hash values between backend and guest
frontend.
This patch adds code to xen-netback to pass hash values calculated for
guest receive-side packets (i.e. netback transmit side) to the frontend.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
My recent patch to include/xen/interface/io/netif.h defines a new shared
ring (in addition to the rx and tx rings) for passing control messages
from a VM frontend driver to a backend driver.
A previous patch added the necessary boilerplate for mapping the control
ring from the frontend, should it be created. This patch adds
implementations for each of the defined protocol messages.
Signed-off-by: Paul Durrant <paul.durrant@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>
My recent patch to include/xen/interface/io/netif.h defines a new shared
ring (in addition to the rx and tx rings) for passing control messages
from a VM frontend driver to a backend driver.
This patch adds the necessary code to xen-netback to map this new shared
ring, should it be created by a frontend, but does not add implementations
for any of the defined protocol messages. These are added in a subsequent
patch for clarity.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Patch 562abd39 "xen-netback: support multiple extra info fragments
passed from frontend" contained a mistake which can result in an in-
correct number of responses being generated when handling errors
encountered when processing packets containing extra info fragments.
This patch fixes the problem.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reported-by: Jan Beulich <JBeulich@suse.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>
The code does not currently support a frontend passing multiple extra info
fragments to the backend in a tx request. The xenvif_get_extras() function
handles multiple extra_info fragments but make_tx_response() assumes there
is only ever a single extra info fragment.
This patch modifies xenvif_get_extras() to pass back a count of extra
info fragments, which is then passed to make_tx_response() (after
possibly being stashed in pending_tx_info for deferred responses).
Signed-off-by: Paul Durrant <paul.durrant@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>
Using the MTU or GSO size to determine the number of required guest Rx
requests for an skb was subtly broken since these value may change at
runtime.
After 1650d5455b (xen-netback: always
fully coalesce guest Rx packets) we always fully pack a packet into
its guest Rx slots. Calculating the number of required slots from the
packet length is then easy.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of open-coding memcpy()s and directly accessing Tx and Rx
requests, use the new RING_COPY_REQUEST() that ensures the local copy
is correct.
This is more than is strictly necessary for guest Rx requests since
only the id and gref fields are used and it is harmless if the
frontend modifies these.
This is part of XSA155.
CC: stable@vger.kernel.org
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The last from guest transmitted request gives no indication about the
minimum amount of credit that the guest might need to send a packet
since the last packet might have been a small one.
Instead allow for the worst case 128 KiB packet.
This is part of XSA155.
CC: stable@vger.kernel.org
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The PV network protocol is using 4KB page granularity. The goal of this
patch is to allow a Linux using 64KB page granularity working as a
network backend on a non-modified Xen.
It's only necessary to adapt the ring size and break skb data in small
chunk of 4KB. The rest of the code is relying on the grant table code.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
The skb doesn't change within the function. Therefore it's only
necessary to check if we need GSO once at the beginning.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
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
Originally that parameter was always reset to num_online_cpus during
module initialisation, which renders it useless.
The fix is to only set max_queues to num_online_cpus when user has not
provided a value.
Reported-by: Johnny Strom <johnny.strom@linuxsolutions.fi>
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit f48da8b14d (xen-netback: fix
unlimited guest Rx internal queue and carrier flapping) introduced a
regression.
The PV frontend in IPXE only places 4 requests on the guest Rx ring.
Since netback required at least (MAX_SKB_FRAGS + 1) slots, IPXE could
not receive any packets.
a) If GSO is not enabled on the VIF, fewer guest Rx slots are required
for the largest possible packet. Calculate the required slots
based on the maximum GSO size or the MTU.
This calculation of the number of required slots relies on
1650d5455b (xen-netback: always fully coalesce guest Rx packets)
which present in 4.0-rc1 and later.
b) Reduce the Rx stall detection to checking for at least one
available Rx request. This is fine since we're predominately
concerned with detecting interfaces which are down and thus have
zero available Rx requests.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
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>
Waking the dealloc thread before decrementing inflight_packets is racy
because it means the thread may go to sleep before inflight_packets is
decremented. If kthread_stop() has already been called, the dealloc
thread may wait forever with nothing to wake it. Instead, wake the
thread only after decrementing inflight_packets.
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Determine if a fraglist is needed in the tx path, and allocate it if
necessary before setting up the copy and map operations.
Otherwise, undoing the copy and map operations is tricky.
This fixes a use-after-free: if allocating the fraglist failed, the copy
and map operations that had been set up were still executed, writing
over the data area of a freed skb.
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The > should be >=. I also added spaces around the '-' operations so
the code is a little more consistent and matches the condition better.
Fixes: f53c3fe8da ('xen-netback: Introduce TX grant mapping')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- Add "make xenconfig" to assist in generating configs for Xen guests.
- Preparatory cleanups necessary for supporting 64 KiB pages in ARM
guests.
- Automatically use hvc0 as the default console in ARM guests.
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Merge tag 'for-linus-4.2-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from David Vrabel:
"Xen features and cleanups for 4.2-rc0:
- add "make xenconfig" to assist in generating configs for Xen guests
- preparatory cleanups necessary for supporting 64 KiB pages in ARM
guests
- automatically use hvc0 as the default console in ARM guests"
* tag 'for-linus-4.2-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
block/xen-blkback: s/nr_pages/nr_segs/
block/xen-blkfront: Remove invalid comment
block/xen-blkfront: Remove unused macro MAXIMUM_OUTSTANDING_BLOCK_REQS
arm/xen: Drop duplicate define mfn_to_virt
xen/grant-table: Remove unused macro SPP
xen/xenbus: client: Fix call of virt_to_mfn in xenbus_grant_ring
xen: Include xen/page.h rather than asm/xen/page.h
kconfig: add xenconfig defconfig helper
kconfig: clarify kvmconfig is for kvm
xen/pcifront: Remove usage of struct timeval
xen/tmem: use BUILD_BUG_ON() in favor of BUG_ON()
hvc_xen: avoid uninitialized variable warning
xenbus: avoid uninitialized variable warning
xen/arm: allow console=hvc0 to be omitted for guests
arm,arm64/xen: move Xen initialization earlier
arm/xen: Correctly check if the event channel interrupt is present
Append 0x to all %x in order to avoid while reading when there is other
decimal value in the log.
Also replace some of the hexadecimal print to decimal to uniformize the
format with netfront.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: netdev@vger.kernel.org
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The variables old_req_cons and ring_slots_used are assigned but never
used since commit 1650d5455b "xen-netback:
always fully coalesce guest Rx packets".
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
Using xen/page.h will be necessary later for using common xen page
helpers.
As xen/page.h already include asm/xen/page.h, always use the later.
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: netdev@vger.kernel.org
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Conflicts:
drivers/net/phy/amd-xgbe-phy.c
drivers/net/wireless/iwlwifi/Kconfig
include/net/mac80211.h
iwlwifi/Kconfig and mac80211.h were both trivial overlapping
changes.
The drivers/net/phy/amd-xgbe-phy.c file got removed in 'net-next' and
the bug fix that happened on the 'net' side is already integrated
into the rest of the amd-xgbe driver.
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/xen-netback/netback.c: In function ‘xenvif_tx_build_gops’:
drivers/net/xen-netback/netback.c:1253:8: warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 5 has type ‘int’ [-Wformat=]
(txreq.offset&~PAGE_MASK) + txreq.size);
^
PAGE_MASK's type can vary by arch, so a cast is needed.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
----
v2: Cast to unsigned long, since PAGE_MASK can vary by arch.
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The variable separate_tx_rx_irq is bool type so assigning true
instead of 1.
Signed-off-by: Shailendra Verma <shailendra.capricorn@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- Use a single source list of hypercalls, generating other tables
etc. at build time.
- Add a "Xen PV" APIC driver to support >255 VCPUs in PV guests.
- Significant performance improve to guest save/restore/migration.
- scsiback/front save/restore support.
- Infrastructure for multi-page xenbus rings.
- Misc fixes.
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Merge tag 'stable/for-linus-4.1-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen features and fixes from David Vrabel:
- use a single source list of hypercalls, generating other tables etc.
at build time.
- add a "Xen PV" APIC driver to support >255 VCPUs in PV guests.
- significant performance improve to guest save/restore/migration.
- scsiback/front save/restore support.
- infrastructure for multi-page xenbus rings.
- misc fixes.
* tag 'stable/for-linus-4.1-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/pci: Try harder to get PXM information for Xen
xenbus_client: Extend interface to support multi-page ring
xen-pciback: also support disabling of bus-mastering and memory-write-invalidate
xen: support suspend/resume in pvscsi frontend
xen: scsiback: add LUN of restored domain
xen-scsiback: define a pr_fmt macro with xen-pvscsi
xen/mce: fix up xen_late_init_mcelog() error handling
xen/privcmd: improve performance of MMAPBATCH_V2
xen: unify foreign GFN map/unmap for auto-xlated physmap guests
x86/xen/apic: WARN with details.
x86/xen: Provide a "Xen PV" APIC driver to support >255 VCPUs
xen/pciback: Don't print scary messages when unsupported by hypervisor.
xen: use generated hypercall symbols in arch/x86/xen/xen-head.S
xen: use generated hypervisor symbols in arch/x86/xen/trace.c
xen: synchronize include/xen/interface/xen.h with xen
xen: build infrastructure for generating hypercall depending symbols
xen: balloon: Use static attribute groups for sysfs entries
xen: pcpu: Use static attribute groups for sysfs entry
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>
Conflicts:
drivers/net/ethernet/emulex/benet/be_main.c
net/core/sysctl_net_core.c
net/ipv4/inet_diag.c
The be_main.c conflict resolution was really tricky. The conflict
hunks generated by GIT were very unhelpful, to say the least. It
split functions in half and moved them around, when the real actual
conflict only existed solely inside of one function, that being
be_map_pci_bars().
So instead, to resolve this, I checked out be_main.c from the top
of net-next, then I applied the be_main.c changes from 'net' since
the last time I merged. And this worked beautifully.
The inet_diag.c and sysctl_net_core.c conflicts were simple
overlapping changes, and were easily to resolve.
Signed-off-by: David S. Miller <davem@davemloft.net>
With the current netback, the bandwidth limiter's parameters are only
settable during vif setup time. This patch register a watch on them, and
thus makes them runtime changeable.
When the watch fires, the timer is reset. The timer's mutex is used for
fencing the change.
Cc: Anthony Liguori <aliguori@amazon.com>
Signed-off-by: Imre Palik <imrep@amazon.de>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This fixes a performance regression introduced by
7fbb9d8415 (xen-netback: release pending
index before pushing Tx responses)
Moving the notify outside of the spin locks means it can be delayed a
long time (if the dealloc thread is descheduled or there is an
interrupt or softirq).
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Zoltan Kiss <zoltan.kiss@linaro.org>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When handling a from-guest frag list, xenvif_handle_frag_list()
replaces the frags before calling the destructor to clean up the
original (foreign) frags. Whilst this is safe (the destructor doesn't
actually use the frags), it looks odd.
Reorder the function to be less confusing.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Every time a VIF is destroyed up to 256 pages may be leaked if packets
with more than MAX_SKB_FRAGS frags were transmitted from the guest.
Even worse, if another user of ballooned pages allocated one of these
ballooned pages it would not handle the unexpectedly >1 page count
(e.g., gntdev would deadlock when unmapping a grant because the page
count would never reach 1).
When handling a from-guest skb with a frag list, unref the frags
before releasing them so they are freed correctly when the VIF is
destroyed.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the pending indexes are released /after/ pushing the Tx response
then a stale pending index may be used if a new Tx request is
immediately pushed by the frontend. The may cause various WARNINGs or
BUGs if the stale pending index is actually still in use.
Fix this by releasing the pending index before pushing the Tx
response.
The full barrier for the pending ring update is not required since the
the Tx response push already has a suitable write barrier.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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
...
- Reworked handling for foreign (grant mapped) pages to simplify the
code, enable a number of additional use cases and fix a number of
long-standing bugs.
- Prefer the TSC over the Xen PV clock when dom0 (and the TSC is
stable).
- Assorted other cleanup and minor bug fixes.
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Merge tag 'stable/for-linus-3.20-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen features and fixes from David Vrabel:
- Reworked handling for foreign (grant mapped) pages to simplify the
code, enable a number of additional use cases and fix a number of
long-standing bugs.
- Prefer the TSC over the Xen PV clock when dom0 (and the TSC is
stable).
- Assorted other cleanup and minor bug fixes.
* tag 'stable/for-linus-3.20-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (25 commits)
xen/manage: Fix USB interaction issues when resuming
xenbus: Add proper handling of XS_ERROR from Xenbus for transactions.
xen/gntdev: provide find_special_page VMA operation
xen/gntdev: mark userspace PTEs as special on x86 PV guests
xen-blkback: safely unmap grants in case they are still in use
xen/gntdev: safely unmap grants in case they are still in use
xen/gntdev: convert priv->lock to a mutex
xen/grant-table: add a mechanism to safely unmap pages that are in use
xen-netback: use foreign page information from the pages themselves
xen: mark grant mapped pages as foreign
xen/grant-table: add helpers for allocating pages
x86/xen: require ballooned pages for grant maps
xen: remove scratch frames for ballooned pages and m2p override
xen/grant-table: pre-populate kernel unmap ops for xen_gnttab_unmap_refs()
mm: add 'foreign' alias for the 'pinned' page flag
mm: provide a find_special_page vma operation
x86/xen: cleanup arch/x86/xen/mmu.c
x86/xen: add some __init annotations in arch/x86/xen/mmu.c
x86/xen: add some __init and static annotations in arch/x86/xen/setup.c
x86/xen: use correct types for addresses in arch/x86/xen/setup.c
...
Conflicts:
drivers/net/vxlan.c
drivers/vhost/net.c
include/linux/if_vlan.h
net/core/dev.c
The net/core/dev.c conflict was the overlap of one commit marking an
existing function static whilst another was adding a new function.
In the include/linux/if_vlan.h case, the type used for a local
variable was changed in 'net', whereas the function got rewritten
to fix a stacked vlan bug in 'net-next'.
In drivers/vhost/net.c, Al Viro's iov_iter conversions in 'net-next'
overlapped with an endainness fix for VHOST 1.0 in 'net'.
In drivers/net/vxlan.c, vxlan_find_vni() added a 'flags' parameter
in 'net-next' whereas in 'net' there was a bug fix to pass in the
correct network namespace pointer in calls to this function.
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit e9d8b2c296 (xen-netback:
disable rogue vif in kthread context), a fatal (protocol) error would
leave the guest Rx thread spinning, wasting CPU time. Commit
ecf08d2dbb (xen-netback: reintroduce
guest Rx stall detection) made this even worse by removing a
cond_resched() from this path.
Since a fatal error is non-recoverable, just allow the guest Rx thread
to exit. This requires taking additional refs to the task so the
thread exiting early is handled safely.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reported-by: Julien Grall <julien.grall@linaro.org>
Tested-by: Julien Grall <julien.grall@linaro.org>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the foreign page flag in netback to get the domid and grant ref
needed for the grant copy. This signficiantly simplifies the netback
code and makes netback work with foreign pages from other backends
(e.g., blkback).
This allows blkback to use iSCSI disks provided by domUs running on
the same host.
Signed-off-by: Jennifer Herbert <jennifer.herbert@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Ballooned pages are always used for grant maps which means the
original frame does not need to be saved in page->index nor restored
after the grant unmap.
This allows the workaround in netback for the conflicting use of the
(unionized) page->index and page->pfmemalloc to be removed.
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>
Always fully coalesce guest Rx packets into the minimum number of ring
slots. Reducing the number of slots per packet has significant
performance benefits when receiving off-host traffic.
Results from XenServer's performance benchmarks:
Baseline Full coalesce
Interhost VM receive 7.2 Gb/s 11 Gb/s
Interhost aggregate 24 Gb/s 24 Gb/s
Intrahost single stream 14 Gb/s 14 Gb/s
Intrahost aggregate 34 Gb/s 34 Gb/s
However, this can increase the number of grant ops per packet which
decreases performance of backend (dom0) to VM traffic (by ~10%)
/unless/ grant copy has been optimized for adjacent ops with the same
source or destination (see "grant-table: defer releasing pages
acquired in a grant copy"[1] expected in Xen 4.6).
[1] http://lists.xen.org/archives/html/xen-devel/2015-01/msg01118.html
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit bc96f648df (xen-netback: make
feature-rx-notify mandatory) incorrectly assumed that there were no
frontends in use that did not support this feature. But the frontend
driver in MiniOS does not and since this is used by (qemu) stubdoms,
these stopped working.
Netback sort of works as-is in this mode except:
- If there are no Rx requests and the internal Rx queue fills, only
the drain timeout will wake the thread. The default drain timeout
of 10 s would give unacceptable pauses.
- If an Rx stall was detected and the internal Rx queue is drained,
then the Rx thread would never wake.
Handle these two cases (when feature-rx-notify is disabled) by:
- Reducing the drain timeout to 30 ms.
- Disabling Rx stall detection.
Reported-by: John <jw@nuclearfallout.net>
Tested-by: John <jw@nuclearfallout.net>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Unconditionally pulling 128 bytes into the linear area is not required
for:
- security: Every protocol demux starts with pskb_may_pull() to pull
frag data into the linear area, if necessary, before looking at
headers.
- performance: Netback has already grant copied up-to 128 bytes from
the first slot of a packet into the linear area. The first slot
normally contain all the IPv4/IPv6 and TCP/UDP headers.
The unconditional pull would often copy frag data unnecessarily. This
is a performance problem when running on a version of Xen where grant
unmap avoids TLB flushes for pages which are not accessed. TLB
flushes can now be avoided for > 99% of unmaps (it was 0% before).
Grant unmap TLB flush avoidance will be available in a future version
of Xen (probably 4.6).
Signed-off-by: Malcolm Crossley <malcolm.crossley@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This flag is unnecessary, it came from some old code.
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Zoltan Kiss <zoltan.kiss@linaro.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If a frontend not receiving packets it is useful to detect this and
turn off the carrier so packets are dropped early instead of being
queued and drained when they expire.
A to-guest queue is stalled if it doesn't have enough free slots for a
an extended period of time (default 60 s).
If at least one queue is stalled, the carrier is turned off (in the
expectation that the other queues will soon stall as well). The
carrier is only turned on once all queues are ready.
When the frontend connects, all the queues start in the stalled state
and only become ready once the frontend queues enough Rx requests.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Netback needs to discard old to-guest skb's (guest Rx queue drain) and
it needs detect guest Rx stalls (to disable the carrier so packets are
discarded earlier), but the current implementation is very broken.
1. The check in hard_start_xmit of the slot availability did not
consider the number of packets that were already in the guest Rx
queue. This could allow the queue to grow without bound.
The guest stops consuming packets and the ring was allowed to fill
leaving S slot free. Netback queues a packet requiring more than S
slots (ensuring that the ring stays with S slots free). Netback
queue indefinately packets provided that then require S or fewer
slots.
2. The Rx stall detection is not triggered in this case since the
(host) Tx queue is not stopped.
3. If the Tx queue is stopped and a guest Rx interrupt occurs, netback
will consider this an Rx purge event which may result in it taking
the carrier down unnecessarily. It also considers a queue with
only 1 slot free as unstalled (even though the next packet might
not fit in this).
The internal guest Rx queue is limited by a byte length (to 512 Kib,
enough for half the ring). The (host) Tx queue is stopped and started
based on this limit. This sets an upper bound on the amount of memory
used by packets on the internal queue.
This allows the estimatation of the number of slots for an skb to be
removed (it wasn't a very good estimate anyway). Instead, the guest
Rx thread just waits for enough free slots for a maximum sized packet.
skbs queued on the internal queue have an 'expires' time (set to the
current time plus the drain timeout). The guest Rx thread will detect
when the skb at the head of the queue has expired and discard expired
skbs. This sets a clear upper bound on the length of time an skb can
be queued for. For a guest being destroyed the maximum time needed to
wait for all the packets it sent to be dropped is still the drain
timeout (10 s) since it will not be sending new packets.
Rx stall detection is reintroduced in a later commit.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reference count the number of packets in host stack, so that we don't
stop the deallocation thread too early. If not, we can end up with
xenvif_free permanently waiting for deallocation thread to unmap grefs.
Reported-by: Thomas Leonard <talex5@gmail.com>
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Zoltan Kiss <zoltan.kiss@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Paul Durrant