Kernel-side struct msghdr is (currently) using the same layout as
userland one, but it's not a one-to-one copy - even without considering
32bit compat issues, we have msg_iov, msg_name and msg_control copied
to kernel[1].  It's fairly localized, so we get away with a few functions
where that knowledge is needed (and we could shrink that set even
more).  Pretty much everything deals with the kernel-side variant and
the few places that want userland one just use a bunch of force-casts
to paper over the differences.

The thing is, kernel-side definition of struct msghdr is *not* exposed
in include/uapi - libc doesn't see it, etc.  So we can add struct user_msghdr,
with proper annotations and let the few places that ever deal with those
beasts use it for userland pointers.  Saner typechecking aside, that will
allow to change the layout of kernel-side msghdr - e.g. replace
msg_iov/msg_iovlen there with struct iov_iter, getting rid of the need
to modify the iovec as we copy data to/from it, etc.

We could introduce kernel_msghdr instead, but that would create much more
noise - the absolute majority of the instances would need to have the
type switched to kernel_msghdr and definition of struct msghdr in
include/linux/socket.h is not going to be seen by userland anyway.

This commit just introduces user_msghdr and switches the few places that
are dealing with userland-side msghdr to it.

[1] actually, it's even trickier than that - we copy msg_control for
sendmsg, but keep the userland address on recvmsg.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

- fix NULL pointer dereference:
kernel/bpf/arraymap.c:41 array_map_alloc() error: potential null dereference 'array'.  (kzalloc returns null)
kernel/bpf/arraymap.c:41 array_map_alloc() error: we previously assumed 'array' could be null (see line 40)

- integer overflow check was missing in arraymap
(hashmap checks for overflow via kmalloc_array())

- arraymap can round_up(value_size, 8) to zero. check was missing.

- hashmap was missing zero size check as well, since roundup_pow_of_two() can
truncate into zero

- found a typo in the arraymap comment and unnecessary empty line

Fix all of these issues and make both overflow checks explicit U32 in size.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The __module_get() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

The proc_remove() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

remove unused variable
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Giuseppe Cavallaro says:

====================
stmmac: update driver documentation

Recently many changes have been done inside the driver
so this patch updates the driver's doc for example reviewing
information for the rx and tx processes that are managed
by napi method, adding new information for missing glue-logic files
etc.
Also this reviews and fixes what is reported when run kernel-doc script.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

When run ./scripts/kernel-doc several warnings are reported
so this patch fix them.
Also it reviews many comments and adds new ones.
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds some useful comments inside the common header
file to provide information about the APIs exposed by the driver.
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Recently many changes have been done inside the driver
so this patch updates the driver's doc for example reviewing
information for the rx and tx processes that are managed
by napi method, adding new information for missing glue-logic files
etc.
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

While working on sk_forward_alloc problems reported by Denys
Fedoryshchenko, we found that tcp connect() (and fastopen) do not call
sk_wmem_schedule() for SYN packet (and/or SYN/DATA packet), so
sk_forward_alloc is negative while connect is in progress.

We can fix this by calling regular sk_stream_alloc_skb() both for the
SYN packet (in tcp_connect()) and the syn_data packet in
tcp_send_syn_data()

Then, tcp_send_syn_data() can avoid copying syn_data as we simply
can manipulate syn_data->cb[] to remove SYN flag (and increment seq)

Instead of open coding memcpy_fromiovecend(), simply use this helper.

This leaves in socket write queue clean fast clone skbs.

This was tested against our fastopen packetdrill tests.
Reported-by: Denys Fedoryshchenko <nuclearcat@nuclearcat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

After commit 5d097109
("tun: only queue packets on device"), NETDEV_TX_OK was returned for
dropped packets. This will confuse pktgen since dropped packets were
counted as sent ones.

Fixing this by returning NET_XMIT_DROP to let pktgen count it as error
packet.

Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If icmp_rcv() has successfully processed the incoming ICMP datagram, we
should use consume_skb() rather than kfree_skb() because a hit on the likes
of perf -e skb:kfree_skb is not called-for.
Signed-off-by: Rick Jones <rick.jones2@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Also remove spaces after cast.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

See Documentation/CodingStyle chapter 6.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: David S. Miller <davem@davemloft.net>

Marc Kleine-Budde says:

====================
this is a pull request of 9 patches for net-next/master.

All 9 patches are by Roger Quadros and update the c_can platform
driver. First by improving the initialization sequence of the message
RAM, making use of syscon/regmap. In the later patches support for
various TI SoCs is added.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Lothar Waßmann says:

====================
net: fec: assorted cleanup patches

This patch series is a followup to:
<1415350967-2238-1-git-send-email-LW@KARO-electronics.de>
[PATCHv4 1/1] net: fec: fix regression on i.MX28 introduced by rx_copybreak support
to apply the cleanup patches that were originally sent along with the
bugfix patch.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The return value of swap_buffer() is not used by any caller, thus
remove it.
Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Eliminate the DIV_ROUND_UP() and change the loop counter increment to
4 instead. This results in saving 6 instructions in the functions
assembly code.
Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

when swap_buffer() is being called, we know for sure, that we need to
byte swap the data. Furthermore, this function is called for swapping
data in both directions. Thus cpu_to_be32() is semantically not
correct for all use cases. Use swab32s() to reflect this.
Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

fep->bufdesc_ex is treated as a boolean value, thus declare it as
such.
Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

consistently use TABs for indentation
Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

Alexei Starovoitov says:

====================
implementation of eBPF maps

v1->v2:
renamed flags for MAP_UPDATE_ELEM command to be more concise,
clarified commit logs and improved comments in patches 1,3,7
per discussions with Daniel

Old v1 cover:

this set of patches adds implementation of HASH and ARRAY types of eBPF maps
which were described in manpage in commit b4fc1a46("Merge branch 'bpf-next'")

The difference vs previous version of these patches from August:
- added 'flags' attribute to BPF_MAP_UPDATE_ELEM
- in HASH type implementation removed per-map kmem_cache.
  I was doing kmem_cache_create() for every map to enable selective slub
  debugging to check for overflows and leaks. Now it's not needed, so just
  use normal kmalloc() for map elements.
- added ARRAY type which was mentioned in manpage, but wasn't public yet
- added map testsuite and removed temporary bits from test_stubs

Note, eBPF programs cannot be attached to events yet.
It will come in the next set.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

proper types and function helpers are ready. Use them in verifier testsuite.
Remove temporary stubs
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

expose bpf_map_lookup_elem(), bpf_map_update_elem(), bpf_map_delete_elem()
map accessors to eBPF programs
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

. check error conditions and sanity of hash and array map APIs
. check large maps (that kernel gracefully switches to vmalloc from kmalloc)
. check multi-process parallel access and stress test
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

fix errno of BPF_MAP_LOOKUP_ELEM command as bpf manpage
described it in commit b4fc1a46("Merge branch 'bpf-next'"):
-----
BPF_MAP_LOOKUP_ELEM
    int bpf_lookup_elem(int fd, void *key, void *value)
    {
        union bpf_attr attr = {
            .map_fd = fd,
            .key = ptr_to_u64(key),
            .value = ptr_to_u64(value),
        };

        return bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr));
    }
    bpf() syscall looks up an element with given key in  a  map  fd.
    If  element  is found it returns zero and stores element's value
    into value.  If element is not found  it  returns  -1  and  sets
    errno to ENOENT.

and further down in manpage:

   ENOENT For BPF_MAP_LOOKUP_ELEM or BPF_MAP_DELETE_ELEM,  indicates  that
          element with given key was not found.
-----

In general all BPF commands return ENOENT when map element is not found
(including BPF_MAP_GET_NEXT_KEY and BPF_MAP_UPDATE_ELEM with
 flags == BPF_MAP_UPDATE_ONLY)

Subsequent patch adds a testsuite to check return values for all of
these combinations.
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

add new map type BPF_MAP_TYPE_ARRAY and its implementation

- optimized for fastest possible lookup()
  . in the future verifier/JIT may recognize lookup() with constant key
    and optimize it into constant pointer. Can optimize non-constant
    key into direct pointer arithmetic as well, since pointers and
    value_size are constant for the life of the eBPF program.
    In other words array_map_lookup_elem() may be 'inlined' by verifier/JIT
    while preserving concurrent access to this map from user space

- two main use cases for array type:
  . 'global' eBPF variables: array of 1 element with key=0 and value is a
    collection of 'global' variables which programs can use to keep the state
    between events
  . aggregation of tracing events into fixed set of buckets

- all array elements pre-allocated and zero initialized at init time

- key as an index in array and can only be 4 byte

- map_delete_elem() returns EINVAL, since elements cannot be deleted

- map_update_elem() replaces elements in an non-atomic way
  (for atomic updates hashtable type should be used instead)
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

add new map type BPF_MAP_TYPE_HASH and its implementation

- maps are created/destroyed by userspace. Both userspace and eBPF programs
  can lookup/update/delete elements from the map

- eBPF programs can be called in_irq(), so use spin_lock_irqsave() mechanism
  for concurrent updates

- key/value are opaque range of bytes (aligned to 8 bytes)

- user space provides 3 configuration attributes via BPF syscall:
  key_size, value_size, max_entries

- map takes care of allocating/freeing key/value pairs

- map_update_elem() must fail to insert new element when max_entries
  limit is reached to make sure that eBPF programs cannot exhaust memory

- map_update_elem() replaces elements in an atomic way

- optimized for speed of lookup() which can be called multiple times from
  eBPF program which itself is triggered by high volume of events
  . in the future JIT compiler may recognize lookup() call and optimize it
    further, since key_size is constant for life of eBPF program
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

the current meaning of BPF_MAP_UPDATE_ELEM syscall command is:
either update existing map element or create a new one.
Initially the plan was to add a new command to handle the case of
'create new element if it didn't exist', but 'flags' style looks
cleaner and overall diff is much smaller (more code reused), so add 'flags'
attribute to BPF_MAP_UPDATE_ELEM command with the following meaning:
 #define BPF_ANY	0 /* create new element or update existing */
 #define BPF_NOEXIST	1 /* create new element if it didn't exist */
 #define BPF_EXIST	2 /* update existing element */

bpf_update_elem(fd, key, value, BPF_NOEXIST) call can fail with EEXIST
if element already exists.

bpf_update_elem(fd, key, value, BPF_EXIST) can fail with ENOENT
if element doesn't exist.

Userspace will call it as:
int bpf_update_elem(int fd, void *key, void *value, __u64 flags)
{
    union bpf_attr attr = {
        .map_fd = fd,
        .key = ptr_to_u64(key),
        .value = ptr_to_u64(value),
        .flags = flags;
    };

    return bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
}

First two bits of 'flags' are used to encode style of bpf_update_elem() command.
Bits 2-63 are reserved for future use.
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jeff Kirsher says:

====================
Intel Wired LAN Driver Updates 2014-11-18

This series contains updates to i40e only.

Shannon provides a patch to clean up the driver to only warn once that
PTP is not supported when linked at 100Mbps.

Mitch provides a fix for i40e where the VF interrupt processing takes
a long time and it is possible that we could lose a VFLR event if it
happens while processing a VFLR on another VF.  To correct this situation,
we enable the VFLR interrupt cause before we begin processing any pending
resets.

Neerav provides several patches to update DCB support in i40e.  When
there are DCB configuration changes based on DCBx, the firmware suspends
the port's Tx and generates an event to the PF.  The PF is then
responsible to reconfigure the PF VSIs and switching topology as per the
updated DCB configuration and then resume the port's Tx by calling the
"Resume Port Tx" AQ command, so add this call to the flow that handles
DCB re-configuration in the PF.  Allow the driver to query and use DCB
configuration from firmware when firmware DCBx agent is in CEE mode.
Add a check whether LLDP Agent's default AdminStatus is enabled or
disabled on a given port, and sets DCBx status to disabled if the
status is disabled.  Fix an issue when the port TC configuration
changes as a result of DCBx and the driver modifies the enabled TCs for
the VEBs it manages but does not update the enabled_tc value that
was cached on a per VEB basis.  Add a new PF state so that if a port's
Tx is in suspended state the Tx queue disable flow would just put the
request for the queue to be disabled and return without waiting for the
queue to be actually disabled.  Allows the driver to enable/disable
the XPS based on the number of TCs being enabled for the given VSI.

v2: Dropped patch "i40e: Handle a single mss packet with more than 8 frags"
    while we rework the patch after we test a bit more based on feedback from
    Eric Dumazet.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Reduce duplicated code by unifying
BPF_ALU | BPF_MOD | BPF_X and BPF_ALU | BPF_DIV | BPF_X

CC: Alexei Starovoitov<alexei.starovoitov@gmail.com>
CC: Daniel Borkmann<dborkman@redhat.com>
CC: Philippe Bergheaud<felix@linux.vnet.ibm.com>
Signed-off-by: Denis Kirjanov <kda@linux-powerpc.org>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Due to DCBX configuration change if the VSI needs to use more than 1 TC;
it needs to disable the XPS maps that were set when operating in 1 TC mode.
Without disabling XPS the netdev layer will select queues based on those
settings and not use the TC queue mapping to make the queue selection.

This patch allows the driver to enable/disable the XPS based on the number
of TCs being enabled for the given VSI.

Change-ID: Idc4dec47a672d2a509f6d7fe11ed1ee65b4f0e08
Signed-off-by: Neerav Parikh <neerav.parikh@intel.com>
Tested-By: Jack Morgan <jack.morgan@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>