Extend the map_perf_test_{user,kern}.c infrastructure to stress test
lpm-trie lookups. We hook into the kprobe on sys_gettid() and measure
the latency depending on trie size and lookup count.
On my Intel Haswell i7-6400U, a single gettid() syscall with an empty
bpf program takes roughly 6.5us on my system. Lookups in empty tries
take ~1.8us on first try, ~0.9us on retries. Lookups in tries with 8192
entries take ~7.1us (on the first _and_ any subsequent try).
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Mack <daniel@zonque.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The first part of this program runs randomized tests against the
lpm-bpf-map. It implements a "Trivial Longest Prefix Match" (tlpm)
based on simple, linear, single linked lists. The implementation
should be pretty straightforward.
Based on tlpm, this inserts randomized data into bpf-lpm-maps and
verifies the trie-based bpf-map implementation behaves the same way
as tlpm.
The second part uses 'real world' IPv4 and IPv6 addresses and tests
the trie with those.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Daniel Mack <daniel@zonque.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This trie implements a longest prefix match algorithm that can be used
to match IP addresses to a stored set of ranges.
Internally, data is stored in an unbalanced trie of nodes that has a
maximum height of n, where n is the prefixlen the trie was created
with.
Tries may be created with prefix lengths that are multiples of 8, in
the range from 8 to 2048. The key used for lookup and update operations
is a struct bpf_lpm_trie_key, and the value is a uint64_t.
The code carries more information about the internal implementation.
Signed-off-by: Daniel Mack <daniel@zonque.org>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Declare net_device_ops structure as const as it is only stored in
the netdev_ops field of a net_device structure. This field is of type
const, so net_device_ops structures having same properties can be made
const too.
Done using Coccinelle:
@r1 disable optional_qualifier@
identifier i;
position p;
@@
static struct net_device_ops i@p={...};
@ok1@
identifier r1.i;
position p;
struct net_device ndev;
@@
ndev.netdev_ops=&i@p
@bad@
position p!={r1.p,ok1.p};
identifier r1.i;
@@
i@p
@depends on !bad disable optional_qualifier@
identifier r1.i;
@@
+const
struct net_device_ops i;
File size before:
text data bss dec hex filename
6201 744 0 6945 1b21 ethernet/xilinx/xilinx_emaclite.o
File size after:
text data bss dec hex filename
6745 192 0 6937 1b19 ethernet/xilinx/xilinx_emaclite.o
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Declare net_device_ops structure as const as it is only stored in
the netdev_ops field of a net_device structure. This field is of type
const, so net_device_ops structures having same properties can be made
const too.
Done using Coccinelle:
@r1 disable optional_qualifier@
identifier i;
position p;
@@
static struct net_device_ops i@p={...};
@ok1@
identifier r1.i;
position p;
struct net_device ndev;
@@
ndev.netdev_ops=&i@p
@bad@
position p!={r1.p,ok1.p};
identifier r1.i;
@@
i@p
@depends on !bad disable optional_qualifier@
identifier r1.i;
@@
+const
struct net_device_ops i;
File size before:
text data bss dec hex filename
4821 744 0 5565 15bd ethernet/moxa/moxart_ether.o
File size after:
text data bss dec hex filename
5373 192 0 5565 15bd ethernet/moxa/moxart_ether.o
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
During reset, functions emac_mac_down() and emac_mac_up() are called,
so we don't want to free and claim the IRQ unnecessarily. Move those
operations to open/close.
Signed-off-by: Timur Tabi <timur@codeaurora.org>
Reviewed-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The EMAC has an internal PHY that is often called the "SGMII". This
SGMII is also connected to an external PHY, which is managed by phylib.
These dual PHYs often cause confusion. In this case, the data structure
for managing the SGMII was mis-named and located in the wrong header file.
Structure emac_phy is renamed to emac_sgmii to clearly indicate it applies
to the internal PHY only. It also also moved from emac_phy.h (which
supports the external PHY) to emac_sgmii.h (where it belongs).
To keep the changes minimal, only the structure name is changed, not
the names of any variables of that type.
Signed-off-by: Timur Tabi <timur@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 4cace675d6 ("bnx2x: Alloc 4k fragment for each rx ring buffer
element") added extra put_page() and get_page() calls on arches where
PAGE_SIZE=4K like x86
Reorder things to avoid this overhead.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com>
Cc: Yuval Mintz <Yuval.Mintz@cavium.com>
Cc: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Fainelli says:
====================
net: dsa: bcm_sf2: Add support for BCM7278
This patch series adds support for the Broadcom BCM7278 integrated switch
which is a successor of the BCM7445 switch. We have a little bit of
register shuffling going on, which is why most of the functional changes
are to deal with that.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement the HW design team recommended workaround in for 7278. Since
the GPHY now returns its revision information in MII_PHYS_ID[23] we need
to check whether the revision provided in flags is 0 or not.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for the BCM7278 28nm process Gigabit Ethernet PHY.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Parse the "brcm,use-bcm-hdr" boolean property during ports
identification to fill a bitmask of ports that should have Broadcom tags
enabled. This is needed in some configurations where per-packet metadata
can be exchanged using Broadcom tags between the switch and an on-chip
acceleration device.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation for enabling Broadcom tags on different ports based on
configuration information, dedicate a function that is responsible for
enabling Broadcom tags for a given port and update the IMP port setup to
call it.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for the integrated switch found on BCM7278:
- core_reg_align is set to 1, to force a translation into the target
address space which is 8 bytes aligned
- an alternate SWITCH_REG layout is provided since registers are largely
bit/masks compatible but have different offsets
- conditional for all CORE_STS_OVERRIDE_{IMP,GMII_P} since those got
moved way out of the traditional register space
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation for supporting a new device with a slightly different
register layout, affecting the SWITCH_REG and SWITCH_CORE address
spaces, perform a few preparatory steps:
- allow matching the compatible string against a data description
- convert the SWITCH_REG register accesses into an indirection table
- prepare for supporting a SWITCH_CORE register alignment requirement
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is no point inlining the 32-bit direct register read/write part,
just infer it from the existing macro. This will make it easier to
centralize the address rewriting that we are going to introduce later
on.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Fainelli says:
====================
net: systemport: Add support for SYSTEMPORT lite
This patch series adds support for SYSTEMPORT Lite which is an evolution
of the existing SYSTEMPORT adapter.
The two generations are largely identical as far as the transmit/receive
path are concerned, and there were just a few control path changes here
and there.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Add supporf for the SYSTEMPORT Lite Ethernet controller, this piece of hardware
is largely based on the full-blown SYSTEMPORT and differs in the following:
- no full-blown UniMAC, instead we have the MagicPacket matching from UniMAC at
same offset, and a GMII Interface Block (GIB) for the MAC-level stuff, since
we are always interfaced to an Ethernet switch which is fully Ethernet compliant
shortcuts could be made
- 16 transmit queues, whose interrupts are moved into the first Level-2 interrupt
controller bank
- slight TDMA offset change (a register was inserted after TDMA_STATUS, *sigh*)
- 256 RX descriptors (512 words) and 256 TX descriptors (not visible)
As a consequence of these two things, update the code paths accordingly to
differentiate the full-blown from the light version.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation for adding SYSTEMPORT Lite, which has twice as less transmit
queues than SYSTEMPORT make sure we do allocate TX rings based on the
systemport,txq property to get an appropriate memory footprint.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since we allocate per cpu storage, let's also use NUMA hints.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes the LS mask when setting EEE timer.
LS field is 10 bits long and not 11 as currently.
Signed-off-by: Joao Pinto <jpinto@synopsys.com>
Reported-By: Rayagond Kokatanur <rayagond@vayavyalabs.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To make the code clearer, use rb_entry() instead of container_of() to
deal with rbtree.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To make the code clearer, use rb_entry() instead of container_of() to
deal with rbtree.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Andrew Lunn says:
====================
net: dsa: Move temperature sensor code into PHY.
Marvell Ethernet switches contain a temperature sensor. There appears
to be one sensor, which is shared by each of the internal PHYs. Each
PHY has independent registers to read this sensor, and to set a limit
for when an alarm should be raised.
Some Marvell discrete PHY also have the same sensor and registers.
Moving the HWMON code from DSA into the PHY makes the sensor available
in discrete PHYs, and removes the layering violation, the switch
driver poking around in PHY registers.
While moving the code into the PHY driver, it has been re-written to
use the new HWMON APIs.
v2:
Better Cover note explaining one sensor, but multiple independent
registers
Simply error checking.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Only the Marvell mv88e6xxx DSA driver made use of the HWMON support in
DSA. The temperature sensor registers are actually in the embedded
PHYs, and the PHY driver now supports it. So remove all HWMON support
from DSA and drivers.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some Marvell PHYs have an inbuilt temperature sensor. Add hwmon
support for this sensor.
There are two different variants. The simpler, older chips have a 5
degree accuracy. The newer devices have 1 degree accuracy.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
When comparing two sockets we need to use inet6_rcv_saddr so we get a NULL
sk_v6_rcv_saddr if the socket isn't AF_INET6, otherwise our comparison function
can be wrong.
Fixes: 637bc8b ("inet: reset tb->fastreuseport when adding a reuseport sk")
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This series includes some updates for mlx5 core and mlx5e netdevice driver.
From Leon, a small fix that remove an unnecessary print.
From Eli Cohen, a fix to the FW version printout in case of internal error.
From Eugenia Emantayev, two patches, the 1st adds mlx5 1pps (pulse per
second) mlx5 infrastructure support and the 2nd adds the necessary bits
for mlx5e ptp logic and structures.
From Mohamad, add support for s-tagged packet receive when in promiscuous
mode.
Form Gal Pressman, MCAM (Management capabilities mask register) and PCAM
(Ports capabilities mask register) registers infrastructure, those
registers are needed in order to query the different statistics registers
support in FW, in order for the driver to enable/disable query and
reporting them back to user. On top of this infrastructure we've exposed
new set of statistics groups:
- MPCNT: Physical layer statistical counters (For symbol errors)
- PPCNT: PCIe performance counters
In addition to the statistics capabilities series we've moved the mlx5 HCA
capabilities fields to a dedicated struct under the driver private data.
At the end a small patch to update & query statistics in the most desired
order.
Thanks,
Saeed.
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Merge tag 'mlx5-updates-2017-01-19' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux
Saeed Mahameed says:
====================
mlx5 and mlx5e updates 2017-01-19
This series includes some updates for mlx5 core and mlx5e netdevice driver.
From Leon, a small fix that remove an unnecessary print.
From Eli Cohen, a fix to the FW version printout in case of internal error.
From Eugenia Emantayev, two patches, the 1st adds mlx5 1pps (pulse per
second) mlx5 infrastructure support and the 2nd adds the necessary bits
for mlx5e ptp logic and structures.
From Mohamad, add support for s-tagged packet receive when in promiscuous
mode.
Form Gal Pressman, MCAM (Management capabilities mask register) and PCAM
(Ports capabilities mask register) registers infrastructure, those
registers are needed in order to query the different statistics registers
support in FW, in order for the driver to enable/disable query and
reporting them back to user. On top of this infrastructure we've exposed
new set of statistics groups:
- MPCNT: Physical layer statistical counters (For symbol errors)
- PPCNT: PCIe performance counters
In addition to the statistics capabilities series we've moved the mlx5 HCA
capabilities fields to a dedicated struct under the driver private data.
At the end a small patch to update & query statistics in the most desired
order.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Ivan Khoronzhuk says:
====================
net: ethernet: ti: cpsw: correct common res usage
This series is intended to remove unneeded redundancies connected with
common resource usage function.
Since v1:
- changed name to cpsw_get_usage_count()
- added comments to open/closw for cpsw_get_usage_count()
- added patch:
net: ethernet: ti: cpsw: clarify ethtool ops changing num of descs
Based on net-next/master
====================
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After adding cpsw_set_ringparam ethtool op, better to carry out
common parts of similar ops splitting descriptors in runtime. It
allows to reuse these parts and shows what the ops actually do.
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
No need to duplicate the same function in rx handler to get info
if any interface is running.
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
No need to create additional vars to identify if interface is running.
So simplify code by removing redundant var and checking usage counter
instead.
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
No need to disable interrupts if no open devices,
they are disabled anyway.
Even no need to disable interrupts if some ndev is opened, In this
case shared resources are not touched, only parameters of ndev shell,
so no reason to disable them also. Removed lines have proved it.
So, no need in redundant check and interrupt disable.
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Common res usage is possible only in case an interface is
running. In case of not dual emac here can be only one interface,
so while ndo_open and switch mode, only one interface can be opened,
thus if open is called no any interface is running ... and no common
res are used. So remove check on dual emac, it will simplify
code/understanding and will match the name it's called.
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Mahesh Bandewar says:
====================
use netdev_is_rx_handler_busy() in few known cases
netdev_rx_handler_register() was recently split into two parts - (a) check
if the handler is used, (b) register the new handler, parts. This is
helpful in scenarios like bonding where at the time of registration there
is too much state to unwind and it should check if the device is free
before building that state. IPvlan and macvlan drivers don't have this
issue however it can make use of the same check instead of using a device
specific check.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
netdev_is_rx_handler_busy() check is a superset of netif_is_ipvlan_port()
check and hence should be preferred.
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
IPvlan checks if the master device is already used by checking a
specific device (here it's macvlan device). This is technically not
sufficient and it should just ensure the rx_handler is busy or not.
This would be a super check that includes macvlan and any other that
has already registered rx-handler.
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
netdev_rx_handler_register() checks to see if the handler is already
busy which was recently separated into netdev_is_rx_handler_busy(). So
use the same function inside register() to avoid code duplication.
Essentially this change should be a no-op
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The fq_codel qdisc currently always regenerates the skb flow hash.
This wastes some cycles and prevents flow seperation in cases where
the traffic has been encrypted and can no longer be understood by the
flow dissector.
Change it to use the prexisting flow hash if one exists, and only
regenerate if necessary.
Signed-off-by: Andrew Collins <acollins@cradlepoint.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eliminate sparse warning by maintaining type of dst_port
as __be16.
Signed-off-by: Lance Richardson <lrichard@redhat.com>
Acked-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cast second parameter of csum_sub() from __sum16 to __wsum.
Signed-off-by: Lance Richardson <lrichard@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jon Maloy says:
====================
tipc: emulate multicast through replication
TIPC multicast messages are currently distributed via L2 broadcast
or IP multicast to all nodes in the cluster, irrespective of the
number of real destinations of the message.
In this series we introduce an option to transport messages via
replication ("replicast") across a selected number of unicast links,
instead of relying on the underlying media. This option is used when
true broadcast/multicast is not supported by the media, or when the
number of true destinations is much smaller than the cluster size.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
If the bearer carrying multicast messages supports broadcast, those
messages will be sent to all cluster nodes, irrespective of whether
these nodes host any actual destinations socket or not. This is clearly
wasteful if the cluster is large and there are only a few real
destinations for the message being sent.
In this commit we extend the eligibility of the newly introduced
"replicast" transmit option. We now make it possible for a user to
select which method he wants to be used, either as a mandatory setting
via setsockopt(), or as a relative setting where we let the broadcast
layer decide which method to use based on the ratio between cluster
size and the message's actual number of destination nodes.
In the latter case, a sending socket must stick to a previously
selected method until it enters an idle period of at least 5 seconds.
This eliminates the risk of message reordering caused by method change,
i.e., when changes to cluster size or number of destinations would
otherwise mandate a new method to be used.
Reviewed-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
TIPC multicast messages are currently carried over a reliable
'broadcast link', making use of the underlying media's ability to
transport packets as L2 broadcast or IP multicast to all nodes in
the cluster.
When the used bearer is lacking that ability, we can instead emulate
the broadcast service by replicating and sending the packets over as
many unicast links as needed to reach all identified destinations.
We now introduce a new TIPC link-level 'replicast' service that does
this.
Reviewed-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As a further preparation for the upcoming 'replicast' functionality,
we add some necessary structs and functions for looking up and returning
a list of all nodes that host destinations for a given multicast message.
Reviewed-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As a preparation for the 'replicast' functionality we are going to
introduce in the next commits, we need the broadcast base structure to
store whether bearer broadcast is available at all from the currently
used bearer or bearers.
We do this by adding a new function tipc_bearer_bcast_support() to
the bearer layer, and letting the bearer selection function in
bcast.c use this to give a new boolean field, 'bcast_support' the
appropriate value.
Reviewed-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Provide a simple helper with the same semantics of strncpy_from_unsafe():
int bpf_probe_read_str(void *dst, int size, const void *unsafe_addr)
This gives more flexibility to a bpf program. A typical use case is
intercepting a file name during sys_open(). The current approach is:
SEC("kprobe/sys_open")
void bpf_sys_open(struct pt_regs *ctx)
{
char buf[PATHLEN]; // PATHLEN is defined to 256
bpf_probe_read(buf, sizeof(buf), ctx->di);
/* consume buf */
}
This is suboptimal because the size of the string needs to be estimated
at compile time, causing more memory to be copied than often necessary,
and can become more problematic if further processing on buf is done,
for example by pushing it to userspace via bpf_perf_event_output(),
since the real length of the string is unknown and the entire buffer
must be copied (and defining an unrolled strnlen() inside the bpf
program is a very inefficient and unfeasible approach).
With the new helper, the code can easily operate on the actual string
length rather than the buffer size:
SEC("kprobe/sys_open")
void bpf_sys_open(struct pt_regs *ctx)
{
char buf[PATHLEN]; // PATHLEN is defined to 256
int res = bpf_probe_read_str(buf, sizeof(buf), ctx->di);
/* consume buf, for example push it to userspace via
* bpf_perf_event_output(), but this time we can use
* res (the string length) as event size, after checking
* its boundaries.
*/
}
Another useful use case is when parsing individual process arguments or
individual environment variables navigating current->mm->arg_start and
current->mm->env_start: using this helper and the return value, one can
quickly iterate at the right offset of the memory area.
The code changes simply leverage the already existent
strncpy_from_unsafe() kernel function, which is safe to be called from a
bpf program as it is used in bpf_trace_printk().
Signed-off-by: Gianluca Borello <g.borello@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Phil Sutter says:
====================
Retrieve number of VFs in a bus-agnostic way
Previously, it was assumed that only PCI NICs would be capable of having
virtual functions - with my proposed enhancement of dummy NIC driver
implementing (fake) ones for testing purposes, this is no longer true.
Discussion of said patch has led to the suggestion of implementing a
bus-agnostic method for VF count retrieval so rtnetlink could work with
both real VF-capable PCI NICs as well as my dummy modifications without
introducing ugly hacks.
The following series tries to achieve just that by introducing a bus
type callback to retrieve a device's number of VFs, implementing this
callback for PCI bus and finally adjusting rtnetlink to make use of the
generalized infrastructure.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that pci_bus_type has num_vf callback set, dev_num_vf can be
implemented in a bus type independent way and the check for whether a
PCI device is being handled in rtnetlink can be dropped.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
