20 Dec, 2018
1 commit
-
Prior this commit, when the struct socket object was being released,
the UMEM did not have its reference count decreased. Instead, this was
done in the struct sock sk_destruct function.There is no reason to keep the UMEM reference around when the socket
is being orphaned, so in this patch the xdp_put_mem is called in the
xsk_release function. This results in that the xsk_destruct function
can be removed!Note that, it still holds that a struct xsk_sock reference might still
linger in the XSKMAP after the UMEM is released, e.g. if a user does
not clear the XSKMAP prior to closing the process. This sock will be
in a "released" zombie like state, until the XSKMAP is removed.Signed-off-by: Björn Töpel
Signed-off-by: Daniel Borkmann
20 Oct, 2018
1 commit
-
net/sched/cls_api.c has overlapping changes to a call to
nlmsg_parse(), one (from 'net') added rtm_tca_policy instead of NULL
to the 5th argument, and another (from 'net-next') added cb->extack
instead of NULL to the 6th argument.net/ipv4/ipmr_base.c is a case of a bug fix in 'net' being done to
code which moved (to mr_table_dump)) in 'net-next'. Thanks to David
Ahern for the heads up.Signed-off-by: David S. Miller
11 Oct, 2018
1 commit
-
The XSKMAP update and delete functions called synchronize_net(), which
can sleep. It is not allowed to sleep during an RCU read section.Instead we need to make sure that the sock sk_destruct (xsk_destruct)
function is asynchronously called after an RCU grace period. Setting
the SOCK_RCU_FREE flag for XDP sockets takes care of this.Fixes: fbfc504a24f5 ("bpf: introduce new bpf AF_XDP map type BPF_MAP_TYPE_XSKMAP")
Reported-by: Eric Dumazet
Signed-off-by: Björn Töpel
Acked-by: Song Liu
Signed-off-by: Daniel Borkmann
08 Oct, 2018
1 commit
-
The AF_XDP socket struct can exist in three different, implicit
states: setup, bound and released. Setup is prior the socket has been
bound to a device. Bound is when the socket is active for receive and
send. Released is when the process/userspace side of the socket is
released, but the sock object is still lingering, e.g. when there is a
reference to the socket in an XSKMAP after process termination.The Rx fast-path code uses the "dev" member of struct xdp_sock to
check whether a socket is bound or relased, and the Tx code uses the
struct xdp_umem "xsk_list" member in conjunction with "dev" to
determine the state of a socket.However, the transition from bound to released did not tear the socket
down in correct order.On the Rx side "dev" was cleared after synchronize_net() making the
synchronization useless. On the Tx side, the internal queues were
destroyed prior removing them from the "xsk_list".This commit corrects the cleanup order, and by doing so
xdp_del_sk_umem() can be simplified and one synchronize_net() can be
removed.Fixes: 965a99098443 ("xsk: add support for bind for Rx")
Fixes: ac98d8aab61b ("xsk: wire upp Tx zero-copy functions")
Reported-by: Jesper Dangaard Brouer
Signed-off-by: Björn Töpel
Acked-by: Song Liu
Signed-off-by: Daniel Borkmann
05 Oct, 2018
3 commits
-
As we now do not allow ethtool to deactivate the queue id we are
running an AF_XDP socket on, we can simplify the implementation of
xdp_clear_umem_at_qid().Signed-off-by: Magnus Karlsson
Signed-off-by: Daniel Borkmann -
We already check the RSS indirection table does not use queues which
would be disabled by channel reconfiguration. Make sure user does not
try to disable queues which have a UMEM and zero-copy AF_XDP socket
installed.Signed-off-by: Jakub Kicinski
Reviewed-by: Quentin Monnet
Signed-off-by: Daniel Borkmann -
Previously, the xsk code did not record which umem was bound to a
specific queue id. This was not required if all drivers were zero-copy
enabled as this had to be recorded in the driver anyway. So if a user
tried to bind two umems to the same queue, the driver would say
no. But if copy-mode was first enabled and then zero-copy mode (or the
reverse order), we mistakenly enabled both of them on the same umem
leading to buggy behavior. The main culprit for this is that we did
not store the association of umem to queue id in the copy case and
only relied on the driver reporting this. As this relation was not
stored in the driver for copy mode (it does not rely on the AF_XDP
NDOs), this obviously could not work.This patch fixes the problem by always recording the umem to queue id
relationship in the netdev_queue and netdev_rx_queue structs. This way
we always know what kind of umem has been bound to a queue id and can
act appropriately at bind time.Signed-off-by: Magnus Karlsson
Signed-off-by: Daniel Borkmann
26 Sep, 2018
1 commit
-
XSK UMEM is strongly single producer single consumer so reuse of
frames is challenging. Add a simple "stash" of FILL packets to
reuse for drivers to optionally make use of. This is useful
when driver has to free (ndo_stop) or resize a ring with an active
AF_XDP ZC socket.Signed-off-by: Jakub Kicinski
Tested-by: Andrew Bowers
Signed-off-by: Jeff Kirsher
01 Sep, 2018
2 commits
-
This commit gets rid of the structure xdp_umem_props. It was there to
be able to break a dependency at one point, but this is no longer
needed. The values in the struct are instead stored directly in the
xdp_umem structure. This simplifies the xsk code as well as af_xdp
zero-copy drivers and as a bonus gets rid of one internal header file.The i40e driver is also adapted to the new interface in this commit.
Signed-off-by: Magnus Karlsson
Signed-off-by: Daniel Borkmann -
Since xdp_umem_query() was added one assignment of bpf.command was
missed from cleanup. Removing the assignment statement.Fixes: 84c6b86875e01a0 ("xsk: don't allow umem replace at stack level")
Signed-off-by: Prashant Bhole
Acked-by: Björn Töpel
Signed-off-by: Daniel Borkmann
30 Aug, 2018
2 commits
-
Previously, the AF_XDP (XDP_DRV/XDP_SKB copy-mode) ingress logic did
not include XDP meta data in the data buffers copied out to the user
application.In this commit, we check if meta data is available, and if so, it is
prepended to the frame.Signed-off-by: Björn Töpel
Signed-off-by: Daniel Borkmann -
Move the xdp_umem_get_{data,dma} functions to include/net/xdp_sock.h,
so that the upcoming zero-copy implementation in the Ethernet drivers
can utilize them.Also, supply some dummy function implementations for
CONFIG_XDP_SOCKETS=n configs.Signed-off-by: Björn Töpel
Signed-off-by: Alexei Starovoitov
22 Aug, 2018
1 commit
-
s/ENOTSUPP/EOPNOTSUPP/ in function umem_assign_dev().
This function's return value is directly returned by xsk_bind().
EOPNOTSUPP is bind()'s possible return value.Fixes: f734607e819b ("xsk: refactor xdp_umem_assign_dev()")
Signed-off-by: Prashant Bhole
Acked-by: Song Liu
Acked-by: Björn Töpel
Signed-off-by: Daniel Borkmann
06 Aug, 2018
1 commit
-
Lots of overlapping changes, mostly trivial in nature.
The mlxsw conflict was resolving using the example
resolution at:https://github.com/jpirko/linux_mlxsw/blob/combined_queue/drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c
Signed-off-by: David S. Miller
03 Aug, 2018
1 commit
-
The BTF conflicts were simple overlapping changes.
The virtio_net conflict was an overlap of a fix of statistics counter,
happening alongisde a move over to a bonafide statistics structure
rather than counting value on the stack.Signed-off-by: David S. Miller
01 Aug, 2018
2 commits
-
Currently drivers have to check if they already have a umem
installed for a given queue and return an error if so. Make
better use of XDP_QUERY_XSK_UMEM and move this functionality
to the core.We need to keep rtnl across the calls now.
Signed-off-by: Jakub Kicinski
Reviewed-by: Quentin Monnet
Acked-by: Björn Töpel
Signed-off-by: David S. Miller -
Return early and only take the ref on dev once there is no possibility
of failing.Signed-off-by: Jakub Kicinski
Reviewed-by: Quentin Monnet
Acked-by: Björn Töpel
Signed-off-by: David S. Miller
31 Jul, 2018
1 commit
-
xdp_return_buff() is used when frame has been successfully
handled (transmitted) or if an error occurred during delayed
processing and there is no way to report it back to
xdp_do_redirect().In case of __xsk_rcv_zc() error is propagated all the way
back to the driver, so there is no need to call
xdp_return_buff(). Driver will recycle the frame anyway
after seeing that error happened.Fixes: 173d3adb6f43 ("xsk: add zero-copy support for Rx")
Signed-off-by: Jakub Kicinski
Acked-by: Björn Töpel
Signed-off-by: Daniel Borkmann
26 Jul, 2018
1 commit
-
Polling for the ingress queues relies on reading the producer/consumer
pointers of the Rx queue.Prior this commit, a cached consumer pointer could be used, instead of
the actual consumer pointer and therefore report POLLIN prematurely.This patch makes sure that the non-cached consumer pointer is used
instead.Reported-by: Qi Zhang
Tested-by: Qi Zhang
Fixes: c497176cb2e4 ("xsk: add Rx receive functions and poll support")
Signed-off-by: Björn Töpel
Signed-off-by: Daniel Borkmann
13 Jul, 2018
4 commits
-
This patch stops returning EMSGSIZE from sendmsg in copy mode when the
size of the packet is larger than the MTU. Just send it to the device
so that it will drop it as in zero-copy mode. This makes the error
reporting consistent between copy mode and zero-copy mode.Fixes: 35fcde7f8deb ("xsk: support for Tx")
Signed-off-by: Magnus Karlsson
Signed-off-by: Daniel Borkmann -
This patch makes sure ENOBUFS is always returned from sendmsg if there
is no TX queue configured. This was not the case for zero-copy
mode. With this patch this error reporting is consistent between copy
mode and zero-copy mode.Fixes: ac98d8aab61b ("xsk: wire upp Tx zero-copy functions")
Signed-off-by: Magnus Karlsson
Signed-off-by: Daniel Borkmann -
This patch stops returning EAGAIN in TX copy mode when the completion
queue is full as zero-copy does not do this. Instead this situation
can be detected by comparing the head and tail pointers of the
completion queue in both modes. In any case, EAGAIN was not the
correct error code here since no amount of calling sendmsg will solve
the problem. Only consuming one or more messages on the completion
queue will fix this.With this patch, the error reporting becomes consistent between copy
mode and zero-copy mode.Fixes: 35fcde7f8deb ("xsk: support for Tx")
Signed-off-by: Magnus Karlsson
Signed-off-by: Daniel Borkmann -
This patch removes the ENXIO return code from TX copy-mode when
someone has forcefully changed the number of queues on the device so
that the queue bound to the socket is no longer available. Just
silently stop sending anything as in zero-copy mode so the error
reporting gets consistent between the two modes.Fixes: 35fcde7f8deb ("xsk: support for Tx")
Signed-off-by: Magnus Karlsson
Signed-off-by: Daniel Borkmann
03 Jul, 2018
3 commits
-
There is a potential race in the TX completion code for the SKB
case. One process enters the sendmsg code of an AF_XDP socket in order
to send a frame. The execution eventually trickles down to the driver
that is told to send the packet. However, it decides to drop the
packet due to some error condition (e.g., rings full) and frees the
SKB. This will trigger the SKB destructor and a completion will be
sent to the AF_XDP user space through its
single-producer/single-consumer queues.At the same time a TX interrupt has fired on another core and it
dispatches the TX completion code in the driver. It does its HW
specific things and ends up freeing the SKB associated with the
transmitted packet. This will trigger the SKB destructor and a
completion will be sent to the AF_XDP user space through its
single-producer/single-consumer queues. With a pseudo call stack, it
would look like this:Core 1:
sendmsg() being called in the application
netdev_start_xmit()
Driver entered through ndo_start_xmit
Driver decides to free the SKB for some reason (e.g., rings full)
Destructor of SKB called
xskq_produce_addr() is called to signal completion to user spaceCore 2:
TX completion irq
NAPI loop
Driver irq handler for TX completions
Frees the SKB
Destructor of SKB called
xskq_produce_addr() is called to signal completion to user spaceWe now have a violation of the single-producer/single-consumer
principle for our queues as there are two threads trying to produce at
the same time on the same queue.Fixed by introducing a spin_lock in the destructor. In regards to the
performance, I get around 1.74 Mpps for txonly before and after the
introduction of the spinlock. There is of course some impact due to
the spin lock but it is in the less significant digits that are too
noisy for me to measure. But let us say that the version without the
spin lock got 1.745 Mpps in the best case and the version with 1.735
Mpps in the worst case, then that would mean a maximum drop in
performance of 0.5%.Fixes: 35fcde7f8deb ("xsk: support for Tx")
Signed-off-by: Magnus Karlsson
Signed-off-by: Alexei Starovoitov -
Fixed a bug in which a frame could be completed more than once
when an error was returned from dev_direct_xmit(). The code
erroneously retried sending the message leading to multiple
calls to the SKB destructor and therefore multiple completions
of the same buffer to user space.The error code in this case has been changed from EAGAIN to EBUSY
in order to tell user space that the sending of the packet failed
and the buffer has been return to user space through the completion
queue.Fixes: 35fcde7f8deb ("xsk: support for Tx")
Signed-off-by: Magnus Karlsson
Reported-by: Pavel Odintsov
Signed-off-by: Alexei Starovoitov -
The code in xskq_produce_addr erroneously checked if there
was up to LAZY_UPDATE_THRESHOLD amount of space in the completion
queue. It only needs to check if there is one slot left in the
queue. This bug could under some circumstances lead to a WARN_ON_ONCE
being triggered and the completion message to user space being lost.Fixes: 35fcde7f8deb ("xsk: support for Tx")
Signed-off-by: Magnus Karlsson
Reported-by: Pavel Odintsov
Signed-off-by: Alexei Starovoitov
29 Jun, 2018
1 commit
-
The poll() changes were not well thought out, and completely
unexplained. They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead. That gets rid of one of the new indirections.But that doesn't fix the new complexity that is completely unwarranted
for the regular case. The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.[ This revert is a revert of about 30 different commits, not reverted
individually because that would just be unnecessarily messy - Linus ]Cc: Al Viro
Cc: Christoph Hellwig
Signed-off-by: Linus Torvalds
12 Jun, 2018
2 commits
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Commit 173d3adb6f43 ("xsk: add zero-copy support for Rx") introduced a
regression on the XDP_SKB receive path, when the queue id checks were
removed. Now, they are back again.Fixes: 173d3adb6f43 ("xsk: add zero-copy support for Rx")
Reported-by: Qi Zhang
Signed-off-by: Björn Töpel
Signed-off-by: Daniel Borkmann -
syzkaller reported a warning from xdp_umem_pin_pages():
WARNING: CPU: 1 PID: 4537 at mm/slab_common.c:996 kmalloc_slab+0x56/0x70 mm/slab_common.c:996
...
__do_kmalloc mm/slab.c:3713 [inline]
__kmalloc+0x25/0x760 mm/slab.c:3727
kmalloc_array include/linux/slab.h:634 [inline]
kcalloc include/linux/slab.h:645 [inline]
xdp_umem_pin_pages net/xdp/xdp_umem.c:205 [inline]
xdp_umem_reg net/xdp/xdp_umem.c:318 [inline]
xdp_umem_create+0x5c9/0x10f0 net/xdp/xdp_umem.c:349
xsk_setsockopt+0x443/0x550 net/xdp/xsk.c:531
__sys_setsockopt+0x1bd/0x390 net/socket.c:1935
__do_sys_setsockopt net/socket.c:1946 [inline]
__se_sys_setsockopt net/socket.c:1943 [inline]
__x64_sys_setsockopt+0xbe/0x150 net/socket.c:1943
do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x49/0xbeThis is a warning about attempting to allocate more than
KMALLOC_MAX_SIZE memory. The request originates from userspace, and if
the request is too big, the kernel is free to deny its allocation. In
this patch, the failed allocation attempt is silenced with
__GFP_NOWARN.Fixes: c0c77d8fb787 ("xsk: add user memory registration support sockopt")
Reported-by: syzbot+4abadc5d69117b346506@syzkaller.appspotmail.com
Signed-off-by: Björn Töpel
Signed-off-by: Daniel Borkmann
08 Jun, 2018
2 commits
-
syzkaller was able to trigger the following panic for AF_XDP:
BUG: KASAN: null-ptr-deref in atomic64_sub include/asm-generic/atomic-instrumented.h:144 [inline]
BUG: KASAN: null-ptr-deref in atomic_long_sub include/asm-generic/atomic-long.h:199 [inline]
BUG: KASAN: null-ptr-deref in xdp_umem_unaccount_pages.isra.4+0x3d/0x80 net/xdp/xdp_umem.c:135
Write of size 8 at addr 0000000000000060 by task syz-executor246/4527CPU: 1 PID: 4527 Comm: syz-executor246 Not tainted 4.17.0+ #89
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1b9/0x294 lib/dump_stack.c:113
kasan_report_error mm/kasan/report.c:352 [inline]
kasan_report.cold.7+0x6d/0x2fe mm/kasan/report.c:412
check_memory_region_inline mm/kasan/kasan.c:260 [inline]
check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
kasan_check_write+0x14/0x20 mm/kasan/kasan.c:278
atomic64_sub include/asm-generic/atomic-instrumented.h:144 [inline]
atomic_long_sub include/asm-generic/atomic-long.h:199 [inline]
xdp_umem_unaccount_pages.isra.4+0x3d/0x80 net/xdp/xdp_umem.c:135
xdp_umem_reg net/xdp/xdp_umem.c:334 [inline]
xdp_umem_create+0xd6c/0x10f0 net/xdp/xdp_umem.c:349
xsk_setsockopt+0x443/0x550 net/xdp/xsk.c:531
__sys_setsockopt+0x1bd/0x390 net/socket.c:1935
__do_sys_setsockopt net/socket.c:1946 [inline]
__se_sys_setsockopt net/socket.c:1943 [inline]
__x64_sys_setsockopt+0xbe/0x150 net/socket.c:1943
do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x49/0xbeIn xdp_umem_reg() the call to xdp_umem_account_pages() passed
with CAP_IPC_LOCK where we didn't need to end up charging rlimit
on memlock for the current user and therefore umem->user continues
to be NULL. Later on through fault injection syzkaller triggered
a failure in either umem->pgs or umem->pages allocation such that
we bail out and undo accounting in xdp_umem_unaccount_pages()
where we eventually hit the panic since it tries to deref the
umem->user.The code is pretty close to mm_account_pinned_pages() and
mm_unaccount_pinned_pages() pair and potentially could reuse
it even in a later cleanup, and it appears that the initial
commit c0c77d8fb787 ("xsk: add user memory registration support
sockopt") got this right while later follow-up introduced the
bug via a49049ea2576 ("xsk: simplified umem setup").Fixes: a49049ea2576 ("xsk: simplified umem setup")
Reported-by: syzbot+979217770b09ebf5c407@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann
Signed-off-by: Alexei Starovoitov -
With gcc-4.1.2 on 32-bit:
net/xdp/xsk.c:663: warning: integer constant is too large for ‘long’ type
net/xdp/xsk.c:665: warning: integer constant is too large for ‘long’ typeAdd the missing "ULL" suffixes to the large XDP_UMEM_PGOFF_*_RING values
to fix this.net/xdp/xsk.c:663: warning: comparison is always false due to limited range of data type
net/xdp/xsk.c:665: warning: comparison is always false due to limited range of data type"unsigned long" is 32-bit on 32-bit systems, hence the offset is
truncated, and can never be equal to any of the XDP_UMEM_PGOFF_*_RING
values. Use loff_t (and the required cast) to fix this.Fixes: 423f38329d267969 ("xsk: add umem fill queue support and mmap")
Fixes: fe2308328cd2f26e ("xsk: add umem completion queue support and mmap")
Signed-off-by: Geert Uytterhoeven
Acked-by: Björn Töpel
Signed-off-by: Daniel Borkmann
07 Jun, 2018
1 commit
-
Pull networking updates from David Miller:
1) Add Maglev hashing scheduler to IPVS, from Inju Song.
2) Lots of new TC subsystem tests from Roman Mashak.
3) Add TCP zero copy receive and fix delayed acks and autotuning with
SO_RCVLOWAT, from Eric Dumazet.4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard
Brouer.5) Add ttl inherit support to vxlan, from Hangbin Liu.
6) Properly separate ipv6 routes into their logically independant
components. fib6_info for the routing table, and fib6_nh for sets of
nexthops, which thus can be shared. From David Ahern.7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP
messages from XDP programs. From Nikita V. Shirokov.8) Lots of long overdue cleanups to the r8169 driver, from Heiner
Kallweit.9) Add BTF ("BPF Type Format"), from Martin KaFai Lau.
10) Add traffic condition monitoring to iwlwifi, from Luca Coelho.
11) Plumb extack down into fib_rules, from Roopa Prabhu.
12) Add Flower classifier offload support to igb, from Vinicius Costa
Gomes.13) Add UDP GSO support, from Willem de Bruijn.
14) Add documentation for eBPF helpers, from Quentin Monnet.
15) Add TLS tx offload to mlx5, from Ilya Lesokhin.
16) Allow applications to be given the number of bytes available to read
on a socket via a control message returned from recvmsg(), from
Soheil Hassas Yeganeh.17) Add x86_32 eBPF JIT compiler, from Wang YanQing.
18) Add AF_XDP sockets, with zerocopy support infrastructure as well.
From Björn Töpel.19) Remove indirect load support from all of the BPF JITs and handle
these operations in the verifier by translating them into native BPF
instead. From Daniel Borkmann.20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha.
21) Allow XDP programs to do lookups in the main kernel routing tables
for forwarding. From David Ahern.22) Allow drivers to store hardware state into an ELF section of kernel
dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy.23) Various RACK and loss detection improvements in TCP, from Yuchung
Cheng.24) Add TCP SACK compression, from Eric Dumazet.
25) Add User Mode Helper support and basic bpfilter infrastructure, from
Alexei Starovoitov.26) Support ports and protocol values in RTM_GETROUTE, from Roopa
Prabhu.27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard
Brouer.28) Add lots of forwarding selftests, from Petr Machata.
29) Add generic network device failover driver, from Sridhar Samudrala.
* ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits)
strparser: Add __strp_unpause and use it in ktls.
rxrpc: Fix terminal retransmission connection ID to include the channel
net: hns3: Optimize PF CMDQ interrupt switching process
net: hns3: Fix for VF mailbox receiving unknown message
net: hns3: Fix for VF mailbox cannot receiving PF response
bnx2x: use the right constant
Revert "net: sched: cls: Fix offloading when ingress dev is vxlan"
net: dsa: b53: Fix for brcm tag issue in Cygnus SoC
enic: fix UDP rss bits
netdev-FAQ: clarify DaveM's position for stable backports
rtnetlink: validate attributes in do_setlink()
mlxsw: Add extack messages for port_{un, }split failures
netdevsim: Add extack error message for devlink reload
devlink: Add extack to reload and port_{un, }split operations
net: metrics: add proper netlink validation
ipmr: fix error path when ipmr_new_table fails
ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds
net: hns3: remove unused hclgevf_cfg_func_mta_filter
netfilter: provide udp*_lib_lookup for nf_tproxy
qed*: Utilize FW 8.37.2.0
...
05 Jun, 2018
4 commits
-
Here we add the functionality required to support zero-copy Tx, and
also exposes various zero-copy related functions for the netdevs.Signed-off-by: Magnus Karlsson
Signed-off-by: Daniel Borkmann -
Extend the xsk_rcv to support the new MEM_TYPE_ZERO_COPY memory, and
wireup ndo_bpf call in bind.Signed-off-by: Björn Töpel
Signed-off-by: Daniel Borkmann -
The xdp_umem_page holds the address for a page. Trade memory for
faster lookup. Later, we'll add DMA address here as well.Signed-off-by: Björn Töpel
Signed-off-by: Daniel Borkmann -
Moved struct xdp_umem to xdp_sock.h, in order to prepare for zero-copy
support.Signed-off-by: Björn Töpel
Signed-off-by: Daniel Borkmann
04 Jun, 2018
3 commits
-
Currently, AF_XDP only supports a fixed frame-size memory scheme where
each frame is referenced via an index (idx). A user passes the frame
index to the kernel, and the kernel acts upon the data. Some NICs,
however, do not have a fixed frame-size model, instead they have a
model where a memory window is passed to the hardware and multiple
frames are filled into that window (referred to as the "type-writer"
model).By changing the descriptor format from the current frame index
addressing scheme, AF_XDP can in the future be extended to support
these kinds of NICs.In the index-based model, an idx refers to a frame of size
frame_size. Addressing a frame in the UMEM is done by offseting the
UMEM starting address by a global offset, idx * frame_size + offset.
Communicating via the fill- and completion-rings are done by means of
idx.In this commit, the idx is removed in favor of an address (addr),
which is a relative address ranging over the UMEM. To convert an
idx-based address to the new addr is simply: addr = idx * frame_size +
offset.We also stop referring to the UMEM "frame" as a frame. Instead it is
simply called a chunk.To transfer ownership of a chunk to the kernel, the addr of the chunk
is passed in the fill-ring. Note, that the kernel will mask addr to
make it chunk aligned, so there is no need for userspace to do
that. E.g., for a chunk size of 2k, passing an addr of 2048, 2050 or
3000 to the fill-ring will refer to the same chunk.On the completion-ring, the addr will match that of the Tx descriptor,
passed to the kernel.Changing the descriptor format to use chunks/addr will allow for
future changes to move to a type-writer based model, where multiple
frames can reside in one chunk. In this model passing one single chunk
into the fill-ring, would potentially result in multiple Rx
descriptors.This commit changes the uapi of AF_XDP sockets, and updates the
documentation.Signed-off-by: Björn Töpel
Signed-off-by: Daniel Borkmann -
Previously, rx_dropped could be updated incorrectly, e.g. if the XDP
program redirected the frame to a socket bound to a different queue
than where the XDP program was executing.Signed-off-by: Björn Töpel
Signed-off-by: Daniel Borkmann -
Previously the fill queue descriptor was not copied to kernel space
prior validating it, making it possible for userland to change the
descriptor post-kernel-validation.Signed-off-by: Björn Töpel
Signed-off-by: Daniel Borkmann
22 May, 2018
1 commit
-
Introduce refcount_t, in favor of atomic_t.
Signed-off-by: Björn Töpel
Signed-off-by: Daniel Borkmann