We always need an RX queue, and there's no reconfig situation either
where we would need to free & rebuild the queue.

So allocate the RX queue right from the start, and avoid freeing it
during unrelated qeth_free_qdio_queues() calls.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jakub Kicinski says:

====================
net: use eth_hw_addr_set() in arch-specific drivers

Fixups for more arch-specific drivers.

With these (and another patch which didn't fit) the build is more or
less clean with all cross-compilers available on kernel.org. I say
more or less because around half of the arches fail to build for
unrelated reasons right now.

Most of the changes here are for m68k, 32bit x86 and alpha.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Byte by byte assignments.

Fixes build on m68k.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Byte by byte assignments.

Fixes build on m68k.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Byte by byte assignments.

Fixes build on m68k.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

dev_addr is set from IO reads, passed to an arch-specific helper.
Note that the helper never reads it so uninitialized temp is fine.

Fixes build on parisc.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

dev_addr is set from IO reads, and broken from a u16 value.

Fixes build on Alpha.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

IO reads, so save to an array then eth_hw_addr_set().

Fixes build on x86 (32bit).
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Use temp to pass to the reading function, the function is generic
so can't fix there.

Fixes m68k build.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Loop with offsetting to every second byte, so use a temp buffer.

Fixes m68k build.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

IO reads, so save to an array then eth_hw_addr_set().

Fixes build on Alpha.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Byte by byte assignments.

Fixes build on m68k.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Byte by byte assignments.

Fixes build on m68k.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Byte by byte assignments.

Fixes build on m68k.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

dev_addr is initialized byte by byte from series.

Fixes build on x86 (32bit).
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

IO reads, so save to an array then eth_hw_addr_set().

Fixes build on x86 (32bit).
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

IO reads, so save to an array then eth_hw_addr_set().

Fixes build on x86 (32bit).
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jakub Kicinski says:

====================
net: constify netdev->dev_addr - x86 changes

Resending these so they can get merged while I battle random cross builds.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Add const to the address param of ipw_send_adapter_address()
all the functions down the chain have already been changed.

Not sure how I lost this in the rebase.
Acked-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Stanislav Yakovlev <stas.yakovlev@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

wilc_set_mac_address() calls IO routines which don't guarantee
the pointer won't be written to. Make a copy.
Acked-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Argument comes from netdev->dev_addr directly, it needs a const.
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

The future is here, convert the new driver as we are about
to make netdev->dev_addr const.
Acked-by: Lukasz Stelmach <l.stelmach@samsung.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Merge tag 'regmap-no-bus-update-bits' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap

Mark Brown says:

===================
regmap: Allow regmap_update_bits() to be offloaded with no bus

Some hardware can do this so let's use that capability.
===================

Link: https://lore.kernel.org/all/YZWDOidBOssP10yS@sirena.org.uk/Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Pull networking fixes from Jakub Kicinski:
 "Including fixes from bpf, mac80211.

  Current release - regressions:

   - devlink: don't throw an error if flash notification sent before
     devlink visible

   - page_pool: Revert "page_pool: disable dma mapping support...",
     turns out there are active arches who need it

  Current release - new code bugs:

   - amt: cancel delayed_work synchronously in amt_fini()

  Previous releases - regressions:

   - xsk: fix crash on double free in buffer pool

   - bpf: fix inner map state pruning regression causing program
     rejections

   - mac80211: drop check for DONT_REORDER in __ieee80211_select_queue,
     preventing mis-selecting the best effort queue

   - mac80211: do not access the IV when it was stripped

   - mac80211: fix radiotap header generation, off-by-one

   - nl80211: fix getting radio statistics in survey dump

   - e100: fix device suspend/resume

  Previous releases - always broken:

   - tcp: fix uninitialized access in skb frags array for Rx 0cp

   - bpf: fix toctou on read-only map's constant scalar tracking

   - bpf: forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing
     progs

   - tipc: only accept encrypted MSG_CRYPTO msgs

   - smc: transfer remaining wait queue entries during fallback, fix
     missing wake ups

   - udp: validate checksum in udp_read_sock() (when sockmap is used)

   - sched: act_mirred: drop dst for the direction from egress to
     ingress

   - virtio_net_hdr_to_skb: count transport header in UFO, prevent
     allowing bad skbs into the stack

   - nfc: reorder the logic in nfc_{un,}register_device, fix unregister

   - ipsec: check return value of ipv6_skip_exthdr

   - usb: r8152: add MAC passthrough support for more Lenovo Docks"

* tag 'net-5.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (96 commits)
  ptp: ocp: Fix a couple NULL vs IS_ERR() checks
  net: ethernet: dec: tulip: de4x5: fix possible array overflows in type3_infoblock()
  net: tulip: de4x5: fix the problem that the array 'lp->phy[8]' may be out of bound
  ipv6: check return value of ipv6_skip_exthdr
  e100: fix device suspend/resume
  devlink: Don't throw an error if flash notification sent before devlink visible
  page_pool: Revert "page_pool: disable dma mapping support..."
  ethernet: hisilicon: hns: hns_dsaf_misc: fix a possible array overflow in hns_dsaf_ge_srst_by_port()
  octeontx2-af: debugfs: don't corrupt user memory
  NFC: add NCI_UNREG flag to eliminate the race
  NFC: reorder the logic in nfc_{un,}register_device
  NFC: reorganize the functions in nci_request
  tipc: check for null after calling kmemdup
  i40e: Fix display error code in dmesg
  i40e: Fix creation of first queue by omitting it if is not power of two
  i40e: Fix warning message and call stack during rmmod i40e driver
  i40e: Fix ping is lost after configuring ADq on VF
  i40e: Fix changing previously set num_queue_pairs for PFs
  i40e: Fix NULL ptr dereference on VSI filter sync
  i40e: Fix correct max_pkt_size on VF RX queue
  ...

Pull btrfs fixes from David Sterba:
 "Several xes and one old ioctl deprecation. Namely there's fix for
  crashes/warnings with lzo compression that was suspected to be caused
  by first pull merge resolution, but it was a different bug.

  Summary:

   - regression fix for a crash in lzo due to missing boundary checks of
     the page array

   - fix crashes on ARM64 due to missing barriers when synchronizing
     status bits between work queues

   - silence lockdep when reading chunk tree during mount

   - fix false positive warning in integrity checker on devices with
     disabled write caching

   - fix signedness of bitfields in scrub

   - start deprecation of balance v1 ioctl"

* tag 'for-5.16-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: deprecate BTRFS_IOC_BALANCE ioctl
  btrfs: make 1-bit bit-fields of scrub_page unsigned int
  btrfs: check-integrity: fix a warning on write caching disabled disk
  btrfs: silence lockdep when reading chunk tree during mount
  btrfs: fix memory ordering between normal and ordered work functions
  btrfs: fix a out-of-bound access in copy_compressed_data_to_page()

Pull UDF fix from Jan Kara:
 "A fix for a long-standing UDF bug where we were not properly
  validating directory position inside readdir"

* tag 'fs_for_v5.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  udf: Fix crash after seekdir

Pull setattr idmapping fix from Christian Brauner:
 "This contains a simple fix for setattr. When determining the validity
  of the attributes the ia_{g,u}id fields contain the value that will be
  written to inode->i_{g,u}id. When the {g,u}id attribute of the file
  isn't altered and the caller's fs{g,u}id matches the current {g,u}id
  attribute the attribute change is allowed.

  The value in ia_{g,u}id does already account for idmapped mounts and
  will have taken the relevant idmapping into account. So in order to
  verify that the {g,u}id attribute isn't changed we simple need to
  compare the ia_{g,u}id value against the inode's i_{g,u}id value.

  This only has any meaning for idmapped mounts as idmapping helpers are
  idempotent without them. And for idmapped mounts this really only has
  a meaning when circular idmappings are used, i.e. mappings where e.g.
  id 1000 is mapped to id 1001 and id 1001 is mapped to id 1000. Such
  ciruclar mappings can e.g. be useful when sharing the same home
  directory between multiple users at the same time.

  Before this patch we could end up denying legitimate attribute changes
  and allowing invalid attribute changes when circular mappings are
  used. To even get into this situation the caller must've been
  privileged both to create that mapping and to create that idmapped
  mount.

  This hasn't been seen in the wild anywhere but came up when expanding
  the fstest suite during work on a series of hardening patches. All
  idmapped fstests pass without any regressions and we're adding new
  tests to verify the behavior of circular mappings.

  The new tests can be found at [1]"

Link: https://lore.kernel.org/linux-fsdevel/20211109145713.1868404-2-brauner@kernel.org [1]

* tag 'fs.idmapped.v5.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  fs: handle circular mappings correctly

Pull parisc fixes from Helge Deller:
 "parisc bug and warning fixes and wire up futex_waitv.

  Fix some warnings which showed up with allmodconfig builds, a revert
  of a change to the sigreturn trampoline which broke signal handling,
  wire up futex_waitv and add CONFIG_PRINTK_TIME=y to 32bit defconfig"

* tag 'for-5.16/parisc-4' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Enable CONFIG_PRINTK_TIME=y in 32bit defconfig
  Revert "parisc: Reduce sigreturn trampoline to 3 instructions"
  parisc: Wrap assembler related defines inside __ASSEMBLY__
  parisc: Wire up futex_waitv
  parisc: Include stringify.h to avoid build error in crypto/api.c
  parisc/sticon: fix reverse colors

Pull KVM fixes from Paolo Bonzini:
 "Selftest changes:

   - Cleanups for the perf test infrastructure and mapping hugepages

   - Avoid contention on mmap_sem when the guests start to run

   - Add event channel upcall support to xen_shinfo_test

  x86 changes:

   - Fixes for Xen emulation

   - Kill kvm_map_gfn() / kvm_unmap_gfn() and broken gfn_to_pfn_cache

   - Fixes for migration of 32-bit nested guests on 64-bit hypervisor

   - Compilation fixes

   - More SEV cleanups

  Generic:

   - Cap the return value of KVM_CAP_NR_VCPUS to both KVM_CAP_MAX_VCPUS
     and num_online_cpus(). Most architectures were only using one of
     the two"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (42 commits)
  KVM: x86: Cap KVM_CAP_NR_VCPUS by KVM_CAP_MAX_VCPUS
  KVM: s390: Cap KVM_CAP_NR_VCPUS by num_online_cpus()
  KVM: RISC-V: Cap KVM_CAP_NR_VCPUS by KVM_CAP_MAX_VCPUS
  KVM: PPC: Cap KVM_CAP_NR_VCPUS by KVM_CAP_MAX_VCPUS
  KVM: MIPS: Cap KVM_CAP_NR_VCPUS by KVM_CAP_MAX_VCPUS
  KVM: arm64: Cap KVM_CAP_NR_VCPUS by kvm_arm_default_max_vcpus()
  KVM: x86: Assume a 64-bit hypercall for guests with protected state
  selftests: KVM: Add /x86_64/sev_migrate_tests to .gitignore
  riscv: kvm: fix non-kernel-doc comment block
  KVM: SEV: Fix typo in and tweak name of cmd_allowed_from_miror()
  KVM: SEV: Drop a redundant setting of sev->asid during initialization
  KVM: SEV: WARN if SEV-ES is marked active but SEV is not
  KVM: SEV: Set sev_info.active after initial checks in sev_guest_init()
  KVM: SEV: Disallow COPY_ENC_CONTEXT_FROM if target has created vCPUs
  KVM: Kill kvm_map_gfn() / kvm_unmap_gfn() and gfn_to_pfn_cache
  KVM: nVMX: Use a gfn_to_hva_cache for vmptrld
  KVM: nVMX: Use kvm_read_guest_offset_cached() for nested VMCS check
  KVM: x86/xen: Use sizeof_field() instead of open-coding it
  KVM: nVMX: Use kvm_{read,write}_guest_cached() for shadow_vmcs12
  KVM: x86/xen: Fix get_attr of KVM_XEN_ATTR_TYPE_SHARED_INFO
  ...

Pull documentation fixes from Jonathan Corbet:
 "A handful of documentation fixes for 5.16"

* tag 'docs-5.16-2' of git://git.lwn.net/linux:
  Documentation/process: fix a cross reference
  Documentation: update vcpu-requests.rst reference
  docs: accounting: update delay-accounting.rst reference
  libbpf: update index.rst reference
  docs: filesystems: Fix grammatical error "with" to "which"
  doc/zh_CN: fix a translation error in management-style
  docs: ftrace: fix the wrong path of tracefs
  Documentation: arm: marvell: Fix link to armada_1000_pb.pdf document
  Documentation: arm: marvell: Put Armada XP section between Armada 370 and 375
  Documentation: arm: marvell: Add some links to homepage / product infos
  docs: Update Sphinx requirements

Pull printk fixes from Petr Mladek:

 - Try to flush backtraces from other CPUs also on the local one. This
   was a regression caused by printk_safe buffers removal.

 - Remove header dependency warning.

* tag 'printk-for-5.16-fixup' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printk: Remove printk.h inclusion in percpu.h
  printk: restore flushing of NMI buffers on remote CPUs after NMI backtraces

The ptp_ocp_get_mem() function does not return NULL, it returns error
pointers.

Fixes: 773bda96 ("ptp: ocp: Expose various resources on the timecard.")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

John Efstathiades says:

===================
lan78xx NAPI Performance Improvements

This patch set introduces a set of changes to the lan78xx driver
that were originally developed as part of an investigation into
the performance of TCP and UDP transfers on an Android system.
The changes increase the throughput of both UDP and TCP transfers
and reduce the overall CPU load.

These improvements are also seen on a standard Linux kernel. Typical
results are included at the end of this document.

The changes to the driver evolved over time. The patches presented
here attempt to organise the changes in to coherent blocks that
affect logically connected parts of the driver. The patches do not
reflect the way in which the code evolved during the performance
investigation.

Each patch produces a working driver that has an incremental
improvement but patches 2, 3 and 6 should be considered a single
update.

The changes affect the following parts of the driver:

1. Deferred URB processing

The deferred URB processing that was originally done by a tasklet
is now done by a NAPI polling routine. The NAPI cycle has a fixed
work budget that controls how many received frames are passed to
the network stack.

Patch 6 introduces the NAPI polling but depends on preceding patches.

The new NAPI polling routine is also responsible for submitting
Rx and Tx URBs to the USB host controller.

Moving the URB processing to a NAPI-based system "smoothed"
incoming and outgoing data flows on the Android system under
investigation. However, taken in isolation, moving from a tasklet
approach to a NAPI approach made little or no difference to the
overall performance.

2. URB buffer management

The driver creates a pool of Tx and a pool of Rx URB buffers. Each
buffer is large enough to accommodate a packet with the maximum MTU
data. URBs are allocated from these pools as required.

Patch 2 introduces the new Tx buffer pool.
Patch 3 introduces the new Rx buffer pool.

3. Tx pending data

SKBs containing data to be transmitted are added to a queue. The
driver tracks free Tx URBs and the corresponding free Tx URB space.
When new Tx URBs are submitted, pending data is copied into the
URB buffer until the URB buffer is filled or there is no more
pending data. This maximises utilisation the LAN78xx internal
USB and network frame buffers.

New Tx URBs are submitted to the USB host controller as part of the
NAPI polling cycle.

Patch 2 introduces these changes.

4. Rx URB completion

A new URB is no longer submitted as part of the URB completion
callback.
New URBs are submitted during the NAPI polling cycle.

Patch 3 introduces these changes.

5. Rx URB processing

Completed URBs are put on to queue for processing (as is done in the
current driver). Network packets in completed URBs are copied from
the URB buffer in to dynamically allocated SKBs and passed to
the network stack.

The emptied URBs are resubmitted to the USB host controller.

Patch 3 introduces this change. Patch 6 updates the change to use
NAPI SKBs.

Each packet passed to the network stack is a single NAPI work item.
If the NAPI work budget is exhausted the remaining packets in the
URB are put onto an overflow queue that is processed at the start
of the next NAPI cycle.

Patch 6 introduces this change.

6. Driver-specific hard_header_len

The driver-specific hard_header_len adjustment was removed as it
broke generic receive offload (GRO) processing. Moreover, it was no
longer required due the change in Tx pending data management (see
point 3. above).

Patch 5 introduces this change.

The modification has been tested on four different target machines:

Target           |    CPU     |   ARCH  | cores | kernel |  RAM  |
-----------------+------------+---------+-------+--------+-------|
Raspberry Pi 4B  | Cortex-A72 | aarch64 |   4   | 64-bit |  2 GB |
Nitrogen8M SBC   | Cortex-A53 | aarch64 |   4   | 64-bit |  2 GB |
Compaq Pressario | Pentium D  | i686    |   2   | 32-bit |  4 GB |
Dell T3620       | Core i3    | x86_64  |  2+2  | 64-bit | 16 GB |

The targets, apart from the Compaq, each have an on-chip USB3 host
controller. A PCIe-based USB3 host controller card was added to the
Compaq to provide the necessary USB3 host interface.

The network throughput was measured using iperf3. The peer device was
a second Dell T3620 fitted with an Intel i210 network interface. The
target machine and the peer device were connected via a Netgear GS105
gigabit switch.

The CPU load was measured using mpstat running on the target machine.

The tables below summarise the throughput and CPU load improvements
achieved by the updated driver.

The bandwidth is the average bandwidth reported by iperf3 at the end
of a 60-second test.

The percentage idle figure is the average idle reported across all
CPU cores on the target machine for the duration of the test.

TCP Rx (target receiving, peer transmitting)

                 |   Standard Driver  |   NAPI Driver      |
Target           | Bandwidth | % Idle | Bandwidth | % Idle |
-----------------+-----------+--------+--------------------|
RPi4 Model B     |    941    |  74.9  |    941    |  91.5  |
Nitrogen8M       |    941    |  76.2  |    941    |  92.7  |
Compaq Pressario |    941    |  44.5  |    941    |  82.1  |
Dell T3620       |    941    |  88.9  |    941    |  98.3  |

TCP Tx (target transmitting, peer receiving)

                 |   Standard Driver  |   NAPI Driver      |
Target           | Bandwidth | % Idle | Bandwidth | % Idle |
-----------------+-----------+--------+--------------------|
RPi4 Model B     |    683    |  80.1  |    942    |  97.6  |
Nitrogen8M       |    942    |  97.8  |    942    |  97.3  |
Compaq Pressario |    939    |  80.0  |    942    |  91.2  |
Dell T3620       |    942    |  95.3  |    942    |  97.6  |

UDP Rx (target receiving, peer transmitting)

                 |   Standard Driver  |   NAPI Driver      |
Target           | Bandwidth | % Idle | Bandwidth | % Idle |
-----------------+-----------+--------+--------------------|
RPi4 Model B     |     -     |    -   | 958 (0%)  |  76.2  |
Nitrogen8M       | 690 (25%) |  57.7  | 937 (0%)  |  68.5  |
Compaq Pressario | 958 (0%)  |  50.2  | 958 (0%)  |  61.6  |
Dell T3620       | 958 (0%)  |  89.6  | 958 (0%)  |  85.3  |

The figure in brackets is the percentage packet loss.

UDP Tx (target transmitting, peer receiving)

                 |   Standard Driver  |   NAPI Driver      |
Target           | Bandwidth | % Idle | Bandwidth | % Idle |
-----------------+-----------+--------+--------------------|
RPi4 Model B     |    370    |  75.0  |    886    |  78.9  |
Nitrogen8M       |    710    |  75.0  |    958    |  85.3  |
Compaq Pressario |    958    |  65.5  |    958    |  76.6  |
Dell T3620       |    958    |  97.0  |    958    |  97.3  |
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch introduces a NAPI-style approach for processing completed
Rx URBs that contributes to improving driver throughput and reducing
CPU load.

Packets in completed URBs are copied to NAPI SKBs and passed to the
network stack for processing. Each frame passed to the stack is one
work item in the NAPI budget.

If the NAPI budget is consumed and frames remain, they are added to
an overflow queue that is processed at the start of the next NAPI
polling cycle.

The NAPI handler is also responsible for copying pending Tx data to
Tx URBs and submitting them to the USB host controller for
transmission.
Signed-off-by: John Efstathiades <john.efstathiades@pebblebay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Remove hardware-specific header length adjustment as it is no longer
required. It also breaks generic receive offload (GRO) processing of
received TCP frames that results in a TCP ACK being sent for each
received frame.
Signed-off-by: John Efstathiades <john.efstathiades@pebblebay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Move position of rx_submit() to remove forward declaration of
rx_complete() which is now no longer required.
Signed-off-by: John Efstathiades <john.efstathiades@pebblebay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch introduces a new approach to allocating and managing
Rx URBs that contributes to improving driver throughput and reducing
CPU load.

A pool of Rx URBs is created during driver instantiation. All the
URBs are initially submitted to the USB host controller for
processing.

The default URB buffer size is different for each USB bus speed.
The chosen sizes provide good USB utilisation with little impact on
overall packet latency.

Completed URBs are processed in the driver bottom half. The URB
buffer contents are copied to a dynamically allocated SKB, which is
then passed to the network stack. The URB is then re-submitted to
the USB host controller.

NOTE: the call to skb_copy() in rx_process() that copies the URB
contents to a new SKB is a temporary change to make this patch work
in its own right. This call will be removed when the NAPI processing
is introduced by patch 6 in this patch set.
Signed-off-by: John Efstathiades <john.efstathiades@pebblebay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch introduces a new approach to allocating and managing
Tx URBs that contributes to improving driver throughput and reducing
CPU load.

A pool of Tx URBs is created during driver instantiation. A URB is
allocated from the pool when there is data to transmit. The URB is
released back to the pool when the data has been transmitted by the
device.

The default URB buffer size is different for each USB bus speed.
The chosen sizes provide good USB utilisation with little impact on
overall packet latency.

SKBs to be transmitted are added to a pending queue for processing.
The driver tracks the available Tx URB buffer space and copies as
much pending data as possible into each free URB. Each full URB
is then submitted to the USB host controller for transmission.
Signed-off-by: John Efstathiades <john.efstathiades@pebblebay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix memory allocation that fails to check for NULL return.
Signed-off-by: John Efstathiades <john.efstathiades@pebblebay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>