This ++ is confusing. It looks duplicated with the one already performed in
'skb_fill_page_desc()'.

In fact, it is harmless. 'nr_frags' is written twice with the same value.
Once, because of the nr_frags++, and once because of the 'nr_frags = i + 1'
in 'skb_fill_page_desc()'.

So axe this post-increment to avoid confusion.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Manish Chopra <manishc@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Some lines of code can be merged into an equivalent 'skb_add_rx_frag()'
call which is less verbose.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>

'page_address(skb_frag_page()) + skb_frag_off()' can be replaced by an
equivalent 'skb_frag_address()' which is less verbose.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>

There is no need to use 'list_for_each_entry_safe' here, as nothing is
removed from the list in the 'for' loop.
Use 'list_for_each_entry' instead, it is slightly less verbose.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>

X.25 Layer 3 (the Packet Layer) expects layer 2 to provide a reliable
datalink service such that no packets are reordered or dropped. And
X.25 Layer 2 (the LAPB layer) is indeed designed to provide such service.

However, this reliability is not preserved when a driver calls "netif_rx"
to deliver the received packets to layer 3, because "netif_rx" will put
the packets into per-CPU queues before they are delivered to layer 3.
If there are multiple CPUs, the order of the packets may not be preserved.
The per-CPU queues may also drop packets if there are too many.

Therefore, we should not call "netif_rx" to let it queue the packets.
Instead, we should use our own queue that won't reorder or drop packets.

This patch changes all X.25 drivers to use their own queues instead of
calling "netif_rx". The patch also documents this requirement in the
"x25-iface" documentation.

Cc: Martin Schiller <ms@dev.tdt.de>
Signed-off-by: Xie He <xie.he.0141@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

'skb_push()'/'skb_postpush_rcsum()' can be replaced by an equivalent
'skb_push_rcsum()' which is less verbose.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>

Saeed Mahameed says:

====================
mlx5-updates-2021-04-02

This series provides trivial updates and cleanup to mlx5 driver

1) Support for matching on ct_state inv and rel flag in connection tracking
2) Reject TC rules that redirect from a VF to itself
3) Parav provided some E-Switch cleanups that could be summarized to:
  3.1) Packing and Reduce structure sizes
  3.2) Dynamic allocation of rate limit tables and structures
4) Vu Makes the netdev arfs and vlan tables allocation dynamic.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Ong Boon Leong says:

====================
stmmac: Add XDP support

This is the v4 patch series for adding XDP native support to stmmac.

Changes in v4:
5/6: Move TX clean timer setup to the end of NAPI RX process and
     group it under stmmac_finalize_xdp_rx().
     Also, fixed stmmac_xdp_xmit_back() returns STMMAC_XDP_CONSUMED
     if XDP buffer conversion to XDP frame fails.

6/6: Move xdp_do_flush(0 into stmmac_finalize_xdp_rx() and combine
     the XDP verdict of XDP TX and XDP REDIRECT together.

I retested the patch series on the 'xdp2' and 'xdp_redirect' related to
changes above and found the result to be satisfactory.

History of previous patch series:
v3: https://patchwork.kernel.org/project/netdevbpf/cover/20210331154135.8507-1-boon.leong.ong@intel.com/
v2: https://patchwork.kernel.org/project/netdevbpf/list/?series=457757
v1: https://patchwork.kernel.org/project/netdevbpf/list/?series=457139

It will be great if community can help to test or review the v4 series
and provide me any input if any.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds the support of XDP_REDIRECT to another remote cpu for
further action. It also implements ndo_xdp_xmit ops, enabling the driver
to transmit packets forwarded to it by XDP program running on another
interface.

This patch has been tested using "xdp_redirect_cpu" for XDP_REDIRECT
+ drop testing. It also been tested with "xdp_redirect" sample app
which can be used to exercise ndo_xdp_xmit ops. The burst traffics are
generated using pktgen_sample03_burst_single_flow.sh in samples/pktgen
directory.

v4: Move xdp_do_flush() processing into stmmac_finalize_xdp_rx() and
    combined the XDP verdict of XDP TX and REDIRECT together.

v3: Added 'nq->trans_start = jiffies' to avoid TX time-out as we are
    sharing TX queue between slow path and XDP. Thanks to Jakub Kicinski
    for point out.
Signed-off-by: Ong Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds support for XDP_TX action which enables XDP program to
transmit back received frames.

This patch has been tested with the "xdp2" app located in samples/bpf
dir. The DUT receives burst traffic packet generated using pktgen script
'pktgen_sample03_burst_single_flow.sh'.

v4: Moved stmmac_tx_timer_arm() to be done once at the end of NAPI RX.
    Fixed stmmac_xdp_xmit_back() to return STMMAC_XDP_CONSUMED if
    XDP buffer to frame conversion fails. Thanks to Jakub's input.

v3: Added 'nq->trans_start = jiffies' to avoid TX time-out as we are
    sharing TX queue between slow path and XDP. Thanks to Jakub Kicinski
    for pointing out.
Signed-off-by: Ong Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch adds the initial XDP support to stmmac driver. It supports
XDP_PASS, XDP_DROP and XDP_ABORTED actions. Upcoming patches will add
support for XDP_TX and XDP_REDIRECT.

To support XDP headroom, this patch adds page_offset into RX buffer and
change the dma_sync_single_for_device|cpu(). The DMA address used for
RX operation are changed to take into page_offset too. As page_pool
can handle dma_sync_single_for_device() on behalf of driver with
PP_FLAG_DMA_SYNC_DEV flag, we skip doing that in stmmac driver.

Current stmmac driver supports split header support (SPH) in RX but
the flexibility of splitting header and payload at different position
makes it very complex to be supported for XDP processing. In addition,
jumbo frame is not supported in XDP to keep the initial codes simple.

This patch has been tested with the sample app "xdp1" located in
samples/bpf directory for both SKB and Native (XDP) mode. The burst
traffic generated using pktgen_sample03_burst_single_flow.sh in
samples/pktgen directory.

Changes in v3:
 - factor in xdp header and tail adjustment done by XDP program.
   Thanks to Jakub Kicinski for pointing out the gap in v2.

Changes in v2:
 - fix for "warning: variable 'len' set but not used" reported by lkp.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Ong Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch organizes TX tail pointer update into a new function called
stmmac_flush_tx_descriptors() so that we can reuse it in stmmac_xmit(),
stmmac_tso_xmit() and up-coming XDP implementation.

Changes to v2:
 - Fix for warning: unused variable ‘desc_size’
   https://patchwork.hopto.org/static/nipa/457321/12170149/build_32bit/stderrSigned-off-by: Ong Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

SPH functionality splits header and payload according to split mode and
offsef fields (SPLM and SPLOFST). It is beneficials for Linux network
stack RX processing however it adds a lot of complexity in XDP
processing.

So, this patch makes the split-header (SPH) capability of the controller
is stored in "priv->sph_cap" and the enabling/disabling of SPH is decided
by "priv->sph".

This is to prepare initial XDP enabling for stmmac to disable the use of
SPH whenever XDP is enabled.
Signed-off-by: Ong Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Certain platform likes Intel mGBE has independent hardware IRQ resources
for TX and RX DMA operation. In preparation to support XDP TX, we add IRQ
affinity hint to group both RX and TX queue of the same queue ID to the
same CPU.

Changes in v2:
 - IRQ affinity hint need to set to null before IRQ is released.
   Thanks to issue reported by Song, Yoong Siang.
Reported-by: Song, Yoong Siang <yoong.siang.song@intel.com>
Signed-off-by: Ong Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Dynamic allocate vlan table in mlx5e_priv for EN netdev
when needed. Don't allocate it for representor netdev.
Signed-off-by: Vu Pham <vuhuong@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Dynamic allocate arfs table in mlx5e_priv for EN netdev
when needed. Don't allocate it for representor netdev.
Signed-off-by: Vu Pham <vuhuong@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Since there are self loopback prevention mechanisms at the
VF level, offloading such rules which redirect from a VF
to itself in the eswitch will break the datapath since the
packets will be dropped once they go back to the vport they
came from.

Therefore, offloading such rules will be rejected and left to
be handled by SW.
Signed-off-by: Ariel Levkovich <lariel@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

ida_simple_alloc() and remove functions are deprecated.
Related change:
commit 3264ceec ("lib/idr.c: document that ida_simple_{get,remove}() are deprecated")
Signed-off-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Function QoS related fields are already defined in qos related struct.
min and max rate are left out to mlx5_vport_info struct.

Move them to existing qos struct.
Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Structure mlx5_vport_info consumes 40 bytes of space due to a hole
in it. After packing it reduces to 32 bytes.

Currently:
pahole -C mlx5_vport_info drivers/net/ethernet/mellanox/mlx5/core/eswitch.o
struct mlx5_vport_info {
        u8                         mac[6];               /*     0     6 */
        u16                        vlan;                 /*     6     2 */
        u8                         qos;                  /*     8     1 */

        /* XXX 7 bytes hole, try to pack */

        u64                        node_guid;            /*    16     8 */
        int                        link_state;           /*    24     4 */
        u32                        min_rate;             /*    28     4 */
        u32                        max_rate;             /*    32     4 */
        bool                       spoofchk;             /*    36     1 */
        bool                       trusted;              /*    37     1 */

        /* size: 40, cachelines: 1, members: 9 */
        /* sum members: 31, holes: 1, sum holes: 7 */
        /* padding: 2 */
        /* last cacheline: 40 bytes */
};

After packing:

$ pahole -C mlx5_vport_info drivers/net/ethernet/mellanox/mlx5/core/eswitch.o

struct mlx5_vport_info {
        u8                         mac[6];               /*     0     6 */
        u16                        vlan;                 /*     6     2 */
        u64                        node_guid;            /*     8     8 */
        int                        link_state;           /*    16     4 */
        u32                        min_rate;             /*    20     4 */
        u32                        max_rate;             /*    24     4 */
        u8                         qos;                  /*    28     1 */
        u8                         spoofchk:1;           /*    29: 0  1 */
        u8                         trusted:1;            /*    29: 1  1 */

        /* size: 32, cachelines: 1, members: 9 */
        /* padding: 2 */
        /* bit_padding: 6 bits */
        /* last cacheline: 32 bytes */
};
Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Add missing mutex_destroy() to pair with mutex_init().

This should be done only when table is initialized, hence perform
mutex_init() only when table is initialized.
Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

A device supports 128 rate limiters. A static table allocation consumes
8KB of memory even when rate is not configured.

Instead, allocate the table when at least one rate is configured.
Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Rate limit entry refcount can be incremented uniformly when it is newly
allocated or reused.
So simplify the code to increment refcount at one place.

Use decrement refcount helper in two routines.
Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

User helper routines to allocate and free rate limit table entries.
Subsequent patch extends use of these helpers to do allocation
during rate entry allocation callback.
Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Table max_size, min and max rate are constants initialized while table
is created. Reading it doesn't need to hold a table mutex. Hence, read
them without holding table mutex.
Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

mlx5_rl_entry structure is not properly packed as shown below. Due to this
an array of size 9144 bytes allocated which is aligned to 16Kbytes.
Hence, pack the structure and avoid the wastage.

This offers 8Kbytes of saving per mlx5_core_dev struct.

pahole -C mlx5_rl_entry  drivers/net/ethernet/mellanox/mlx5/core/en_main.o

Existing layout:

struct mlx5_rl_entry {
        u8                         rl_raw[48];           /*     0    48 */
        u16                        index;                /*    48     2 */

        /* XXX 6 bytes hole, try to pack */

        u64                        refcount;             /*    56     8 */
        /* --- cacheline 1 boundary (64 bytes) --- */
        u16                        uid;                  /*    64     2 */
        u8                         dedicated:1;          /*    66: 0  1 */

        /* size: 72, cachelines: 2, members: 5 */
        /* sum members: 60, holes: 1, sum holes: 6 */
        /* sum bitfield members: 1 bits (0 bytes) */
        /* padding: 5 */
        /* bit_padding: 7 bits */
        /* last cacheline: 8 bytes */
};

After alignment:

struct mlx5_rl_entry {
        u8                         rl_raw[48];           /*     0    48 */
        u64                        refcount;             /*    48     8 */
        u16                        index;                /*    56     2 */
        u16                        uid;                  /*    58     2 */
        u8                         dedicated:1;          /*    60: 0  1 */

        /* size: 64, cachelines: 1, members: 5 */
        /* padding: 3 */
        /* bit_padding: 7 bits */
};
Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Fix the warning due to missing int.

WARNING: Prefer 'unsigned int' to bare use of 'unsigned'
+       unsigned free_count;
Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Function QoS related fields are already defined in qos related struct.
min and max rate are left out to mlx5_vport_info struct.

Move them to existing qos struct.
Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Structure mlx5_vport_info consumes 40 bytes of space due to a hole
in it. After packing it reduces to 32 bytes.

Currently:
pahole -C mlx5_vport_info drivers/net/ethernet/mellanox/mlx5/core/eswitch.o
struct mlx5_vport_info {
        u8                         mac[6];               /*     0     6 */
        u16                        vlan;                 /*     6     2 */
        u8                         qos;                  /*     8     1 */

        /* XXX 7 bytes hole, try to pack */

        u64                        node_guid;            /*    16     8 */
        int                        link_state;           /*    24     4 */
        u32                        min_rate;             /*    28     4 */
        u32                        max_rate;             /*    32     4 */
        bool                       spoofchk;             /*    36     1 */
        bool                       trusted;              /*    37     1 */

        /* size: 40, cachelines: 1, members: 9 */
        /* sum members: 31, holes: 1, sum holes: 7 */
        /* padding: 2 */
        /* last cacheline: 40 bytes */
};

After packing:

$ pahole -C mlx5_vport_info drivers/net/ethernet/mellanox/mlx5/core/eswitch.o

struct mlx5_vport_info {
        u8                         mac[6];               /*     0     6 */
        u16                        vlan;                 /*     6     2 */
        u64                        node_guid;            /*     8     8 */
        int                        link_state;           /*    16     4 */
        u32                        min_rate;             /*    20     4 */
        u32                        max_rate;             /*    24     4 */
        u8                         qos;                  /*    28     1 */
        u8                         spoofchk:1;           /*    29: 0  1 */
        u8                         trusted:1;            /*    29: 1  1 */

        /* size: 32, cachelines: 1, members: 9 */
        /* padding: 2 */
        /* bit_padding: 6 bits */
        /* last cacheline: 32 bytes */
};
Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Add support for matching on ct_state inv and rel flags.

Currently the support is only for match on -inv and -rel.
Matching on +inv and +rel will be rejected.

Example:
$ tc filter add dev ens1f0_0 ingress prio 1 chain 1 proto ip flower \
  ct_state -est-rel+trk \
  action mirred egress redirect dev ens1f0_1
$ tc filter add dev ens1f0_1 ingress prio 1 chain 1 proto ip flower \
  ct_state +trk+est-inv \
  action mirred egress redirect dev ens1f0_0
Signed-off-by: Ariel Levkovich <lariel@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Group all the often used fields in the first cache line,
to reduce cache line misses.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Order fields to increase locality for most used protocols.

udplite and icmp are moved at the end.

Same for proc_net_devsnmp6 which is not used in fast path.

This potentially saves one cache line miss for typical TCP/UDP over IPv4/IPv6.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

If the "type_a->nfcid_len" is too large then it would lead to memory
corruption in pn533_target_found_type_a() when we do:

	memcpy(nfc_tgt->nfcid1, tgt_type_a->nfcid_data, nfc_tgt->nfcid1_len);

Fixes: c3b1e1e8 ("NFC: Export NFCID1 from pn533")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Ioana Ciornei says:

====================
dpaa2-eth: add rx copybreak support

DMA unmapping, allocating a new buffer and DMA mapping it back on the
refill path is really not that efficient. Proper buffer recycling (page
pool, flipping the page and using the other half) cannot be done for
DPAA2 since it's not a ring based controller but it rather deals with
multiple queues which all get their buffers from the same buffer pool on
Rx.

To circumvent these limitations, add support for Rx copybreak in
dpaa2-eth.

Below you can find a summary of the tests that were run to end up
with the default rx copybreak value of 512.
A bit about the setup - a LS2088A SoC, 8 x Cortex A72 @ 1.8GHz, IPfwd
zero loss test @ 20Gbit/s throughput.  I tested multiple frame sizes to
get an idea where is the break even point.

Here are 2 sets of results, (1) is the baseline and (2) is just
allocating a new skb for all frames sizes received (as if the copybreak
was even to the MTU). All numbers are in Mpps.

         64   128    256   512  640   768   896

(1)     3.23  3.23  3.24  3.21  3.1  2.76  2.71
(2)     3.95  3.88  3.79  3.62  3.3  3.02  2.65

It seems that even for 512 bytes frame sizes it's comfortably better when
allocating a new skb. After that, we see diminishing rewards or even worse.

Changes in v2:
 - properly marked dpaa2_eth_copybreak as static
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

It's useful, especially for debugging purposes, to have the Rx copybreak
value changeable at runtime. Export it as an ethtool tunable.
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

DMA unmapping, allocating a new buffer and DMA mapping it back on the
refill path is really not that efficient. Proper buffer recycling (page
pool, flipping the page and using the other half) cannot be done for
DPAA2 since it's not a ring based controller but it rather deals with
multiple queues which all get their buffers from the same buffer pool on
Rx.

To circumvent these limitations, add support for Rx copybreak. For small
sized packets instead of creating a skb around the buffer in which the
frame was received, allocate a new sk buffer altogether, copy the
contents of the frame and release the initial page back into the buffer
pool.
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Rename the dpaa2_eth_xdp_release_buf function into dpaa2_eth_recycle_buf
since in the next patches we'll be using the same recycle mechanism for
the normal stack path beside for XDP_DROP.

Also, rename the array which holds the buffers to be recycled so that it
does not have any reference to XDP.
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

Mat Martineau says:

====================
MPTCP: Miscellaneous changes

Here is a collection of patches from the MPTCP tree:

Patches 1 and 2 add some helpful MIB counters for connection
information.

Patch 3 cleans up some unnecessary checks.

Patch 4 is a new feature, support for the MP_TCPRST option. This option
is used when resetting one subflow within a MPTCP connection, and
provides a reason code that the recipient can use when deciding how to
adapt to the lost subflow.

Patches 5-7 update the existing MPTCP selftests to improve timeout
handling and to share better information when tests fail.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Very occasionally, MPTCP selftests fail. Yeah, I saw that at least once!

Here we provide more details in case of errors with mptcp_join.sh script
like it was done with mptcp_connect.sh, see
commit 767389c8 ("selftests: mptcp: dump more info on errors")
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Not to be impacted by packets sent between sub-tests.
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>