[RFC v2 00/24] Per queue configs and large rx buffer support for zcrx

[RFC v2 00/24] Per queue configs and large rx buffer support for zcrx

[Pavel Begunkov]

This series implements large rx buffer support for io_uring/zcrx on
top of Jakub's queue configuration changes, but it can also be used
by other memory providers. Large rx buffers can be drastically
beneficial with high-end hw-gro enabled cards that can coalesce traffic
into larger pages, reducing the number of frags traversing the network
stack and resuling in larger contiguous chunks of data for the
userspace. Benchamrks showed up to ~30% improvement in CPU util.

For example, for 200Gbit broadcom NIC, 4K vs 32K buffers, and napi and
userspace pinned to the same CPU:

packets=23987040 (MB=2745098), rps=199559 (MB/s=22837)
CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
  0    1.53    0.00   27.78    2.72    1.31   66.45    0.22
packets=24078368 (MB=2755550), rps=200319 (MB/s=22924)
CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
  0    0.69    0.00    8.26   31.65    1.83   57.00    0.57

And for napi and userspace on different CPUs:

packets=10725082 (MB=1227388), rps=198285 (MB/s=22692)
CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
  0    0.10    0.00    0.50    0.00    0.50   74.50    24.40
  1    4.51    0.00   44.33   47.22    2.08    1.85    0.00
packets=14026235 (MB=1605175), rps=198388 (MB/s=22703)
CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
  0    0.10    0.00    0.70    0.00    1.00   43.78   54.42
  1    1.09    0.00   31.95   62.91    1.42    2.63    0.00

Patch 22 allows to pass queue config from a memory provider. Most
of necessary zcrx changes are already queued in a separate branch,
so the zcrx changes are contained in Patch 24 and are fairly
simple. The uAPI is simple and imperative, the buffer length is
passed in the zcrx registration structure, 

Patches 2-21 are taken from Jakub's series with per queue
configuration [1]. Quoting Jakub:

"... The direct motivation for the series is that zero-copy Rx queues would
like to use larger Rx buffers. Most modern high-speed NICs support HW-GRO,
and can coalesce payloads into pages much larger than than the MTU.
Enabling larger buffers globally is a bit precarious as it exposes us
to potentially very inefficient memory use. Also allocating large
buffers may not be easy or cheap under load. Zero-copy queues service
only select traffic and have pre-allocated memory so the concerns don't
apply as much.

The per-queue config has to address 3 problems:
- user API
- driver API
- memory provider API

For user API the main question is whether we expose the config via
ethtool or netdev nl. I picked the latter - via queue GET/SET, rather
than extending the ethtool RINGS_GET API. I worry slightly that queue
GET/SET will turn in a monster like SETLINK. OTOH the only per-queue
settings we have in ethtool which are not going via RINGS_SET is
IRQ coalescing.

My goal for the driver API was to avoid complexity in the drivers.
The queue management API has gained two ops, responsible for preparing
configuration for a given queue, and validating whether the config
is supported. The validating is used both for NIC-wide and per-queue
changes. Queue alloc/start ops have a new "config" argument which
contains the current config for a given queue (we use queue restart
to apply per-queue settings). Outside of queue reset paths drivers
can call netdev_queue_config() which returns the config for an arbitrary
queue. Long story short I anticipate it to be used during ndo_open.

In the core I extended struct netdev_config with per queue settings.
All in all this isn't too far from what was there in my "queue API
prototype" a few years ago ..."

Kernel branch with all dependencies: 
git: https://github.com/isilence/linux.git zcrx/large-buffers-v2
url: https://github.com/isilence/linux/tree/zcrx/large-buffers-v2

Per queue configuration series:
[1] https://lore.kernel.org/all/20250421222827.283737-1-kuba@kernel.org/

v2: - Add MAX_PAGE_ORDER check on pp init (Patch 1)
    - Applied comments rewording (Patch 2)
    - Adjust pp.max_len based on order (Patch 8)
    - Patch up mlx5 queue callbacks after rebase (Patch 12)
    - Minor ->queue_mgmt_ops refactoring (Patch 15)
    - Rebased to account for both fill level and agg_size_fac (Patch 17)
    - Pass providers buf length in struct pp_memory_provider_params and
      apply it in __netdev_queue_confi(). (Patch 22)
    - Use ->supported_ring_params to validate drivers support of set
      qcfg parameters. (Patch 23)

Jakub Kicinski (20):
  docs: ethtool: document that rx_buf_len must control payload lengths
  net: ethtool: report max value for rx-buf-len
  net: use zero value to restore rx_buf_len to default
  net: clarify the meaning of netdev_config members
  net: add rx_buf_len to netdev config
  eth: bnxt: read the page size from the adapter struct
  eth: bnxt: set page pool page order based on rx_page_size
  eth: bnxt: support setting size of agg buffers via ethtool
  net: move netdev_config manipulation to dedicated helpers
  net: reduce indent of struct netdev_queue_mgmt_ops members
  net: allocate per-queue config structs and pass them thru the queue
    API
  net: pass extack to netdev_rx_queue_restart()
  net: add queue config validation callback
  eth: bnxt: always set the queue mgmt ops
  eth: bnxt: store the rx buf size per queue
  eth: bnxt: adjust the fill level of agg queues with larger buffers
  netdev: add support for setting rx-buf-len per queue
  net: wipe the setting of deactived queues
  eth: bnxt: use queue op config validate
  eth: bnxt: support per queue configuration of rx-buf-len

Pavel Begunkov (4):
  net: page_pool: sanitise allocation order
  net: let pp memory provider to specify rx buf len
  net: validate driver supports passed qcfg params
  io_uring/zcrx: implement large rx buffer support

 Documentation/netlink/specs/ethtool.yaml      |   4 +
 Documentation/netlink/specs/netdev.yaml       |  15 ++
 Documentation/networking/ethtool-netlink.rst  |   7 +-
 drivers/net/ethernet/broadcom/bnxt/bnxt.c     | 142 +++++++++++---
 drivers/net/ethernet/broadcom/bnxt/bnxt.h     |   5 +-
 .../net/ethernet/broadcom/bnxt/bnxt_ethtool.c |   9 +-
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c |   6 +-
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h |   2 +-
 drivers/net/ethernet/google/gve/gve_main.c    |   9 +-
 .../marvell/octeontx2/nic/otx2_ethtool.c      |   6 +-
 .../net/ethernet/mellanox/mlx5/core/en_main.c |   9 +-
 drivers/net/netdevsim/netdev.c                |   8 +-
 include/linux/ethtool.h                       |   3 +
 include/net/netdev_queues.h                   |  84 ++++++--
 include/net/netdev_rx_queue.h                 |   3 +-
 include/net/netlink.h                         |  19 ++
 include/net/page_pool/types.h                 |   1 +
 .../uapi/linux/ethtool_netlink_generated.h    |   1 +
 include/uapi/linux/io_uring.h                 |   2 +-
 include/uapi/linux/netdev.h                   |   2 +
 io_uring/zcrx.c                               |  36 +++-
 net/core/Makefile                             |   2 +-
 net/core/dev.c                                |  12 +-
 net/core/dev.h                                |  15 ++
 net/core/netdev-genl-gen.c                    |  15 ++
 net/core/netdev-genl-gen.h                    |   1 +
 net/core/netdev-genl.c                        |  92 +++++++++
 net/core/netdev_config.c                      | 183 ++++++++++++++++++
 net/core/netdev_rx_queue.c                    |  22 ++-
 net/core/page_pool.c                          |   3 +
 net/ethtool/common.c                          |   4 +-
 net/ethtool/netlink.c                         |  14 +-
 net/ethtool/rings.c                           |  14 +-
 tools/include/uapi/linux/netdev.h             |   2 +
 34 files changed, 662 insertions(+), 90 deletions(-)
 create mode 100644 net/core/netdev_config.c

-- 
2.49.0

[RFC v2 01/24] net: page_pool: sanitise allocation order

[Pavel Begunkov]

We're going to give more control over rx buffer sizes to user space, and
since we can't always rely on driver validation, let's sanitise it in
page_pool_init() as well. Note that we only need to reject over
MAX_PAGE_ORDER allocations for normal page pools, as current memory
providers don't need to use the buddy allocator and must check the order
on init.

Suggested-by: Stanislav Fomichev <stfomichev@gmail.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 net/core/page_pool.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index 05e2e22a8f7c..f1373756cd0f 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -303,6 +303,9 @@ static int page_pool_init(struct page_pool *pool,
 		}
 
 		static_branch_inc(&page_pool_mem_providers);
+	} else if (pool->p.order > MAX_PAGE_ORDER) {
+		err = -EINVAL;
+		goto free_ptr_ring;
 	}
 
 	return 0;
-- 
2.49.0

[RFC v2 02/24] docs: ethtool: document that rx_buf_len must control payload lengths

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

Document the semantics of the rx_buf_len ethtool ring param.
Clarify its meaning in case of HDS, where driver may have
two separate buffer pools.

The various zero-copy TCP Rx schemes we have suffer from memory
management overhead. Specifically applications aren't too impressed
with the number of 4kB buffers they have to juggle. Zero-copy
TCP makes most sense with larger memory transfers so using
16kB or 32kB buffers (with the help of HW-GRO) feels more
natural.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 Documentation/networking/ethtool-netlink.rst | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index ab20c644af24..cae372f719d1 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -966,7 +966,6 @@ Kernel checks that requested ring sizes do not exceed limits reported by
 driver. Driver may impose additional constraints and may not support all
 attributes.
 
-
 ``ETHTOOL_A_RINGS_CQE_SIZE`` specifies the completion queue event size.
 Completion queue events (CQE) are the events posted by NIC to indicate the
 completion status of a packet when the packet is sent (like send success or
@@ -980,6 +979,11 @@ completion queue size can be adjusted in the driver if CQE size is modified.
 header / data split feature. If a received packet size is larger than this
 threshold value, header and data will be split.
 
+``ETHTOOL_A_RINGS_RX_BUF_LEN`` controls the size of the buffers driver
+uses to receive packets. If the device uses different buffer pools for
+headers and payload (due to HDS, HW-GRO etc.) this setting must
+control the size of the payload buffers.
+
 CHANNELS_GET
 ============
 
-- 
2.49.0

[RFC v2 03/24] net: ethtool: report max value for rx-buf-len

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

Unlike most of our APIs the rx-buf-len param does not have an associated
max value. In theory user could set this value pretty high, but in
practice most NICs have limits due to the width of the length fields
in the descriptors.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 Documentation/netlink/specs/ethtool.yaml                  | 4 ++++
 Documentation/networking/ethtool-netlink.rst              | 1 +
 drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c | 3 ++-
 include/linux/ethtool.h                                   | 2 ++
 include/uapi/linux/ethtool_netlink_generated.h            | 1 +
 net/ethtool/rings.c                                       | 5 +++++
 6 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/Documentation/netlink/specs/ethtool.yaml b/Documentation/netlink/specs/ethtool.yaml
index 1063d5d32fea..77627f1ec54e 100644
--- a/Documentation/netlink/specs/ethtool.yaml
+++ b/Documentation/netlink/specs/ethtool.yaml
@@ -449,6 +449,9 @@ attribute-sets:
       -
         name: hds-thresh-max
         type: u32
+      -
+        name: rx-buf-len-max
+        type: u32
 
   -
     name: mm-stat
@@ -2046,6 +2049,7 @@ operations:
             - rx-jumbo
             - tx
             - rx-buf-len
+            - rx-buf-len-max
             - tcp-data-split
             - cqe-size
             - tx-push
diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index cae372f719d1..05a7f6b3f945 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -902,6 +902,7 @@ Kernel response contents:
   ``ETHTOOL_A_RINGS_RX_JUMBO``              u32     size of RX jumbo ring
   ``ETHTOOL_A_RINGS_TX``                    u32     size of TX ring
   ``ETHTOOL_A_RINGS_RX_BUF_LEN``            u32     size of buffers on the ring
+  ``ETHTOOL_A_RINGS_RX_BUF_LEN_MAX``        u32     max size of rx buffers
   ``ETHTOOL_A_RINGS_TCP_DATA_SPLIT``        u8      TCP header / data split
   ``ETHTOOL_A_RINGS_CQE_SIZE``              u32     Size of TX/RX CQE
   ``ETHTOOL_A_RINGS_TX_PUSH``               u8      flag of TX Push mode
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c
index 998c734ff839..1c8a7ee2e459 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c
@@ -377,6 +377,7 @@ static void otx2_get_ringparam(struct net_device *netdev,
 	ring->tx_max_pending = Q_COUNT(Q_SIZE_MAX);
 	ring->tx_pending = qs->sqe_cnt ? qs->sqe_cnt : Q_COUNT(Q_SIZE_4K);
 	kernel_ring->rx_buf_len = pfvf->hw.rbuf_len;
+	kernel_ring->rx_buf_len_max = 32768;
 	kernel_ring->cqe_size = pfvf->hw.xqe_size;
 }
 
@@ -399,7 +400,7 @@ static int otx2_set_ringparam(struct net_device *netdev,
 	/* Hardware supports max size of 32k for a receive buffer
 	 * and 1536 is typical ethernet frame size.
 	 */
-	if (rx_buf_len && (rx_buf_len < 1536 || rx_buf_len > 32768)) {
+	if (rx_buf_len && (rx_buf_len < 1536)) {
 		netdev_err(netdev,
 			   "Receive buffer range is 1536 - 32768");
 		return -EINVAL;
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index de5bd76a400c..9267bac16195 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -77,6 +77,7 @@ enum {
 /**
  * struct kernel_ethtool_ringparam - RX/TX ring configuration
  * @rx_buf_len: Current length of buffers on the rx ring.
+ * @rx_buf_len_max: Max length of buffers on the rx ring.
  * @tcp_data_split: Scatter packet headers and data to separate buffers
  * @tx_push: The flag of tx push mode
  * @rx_push: The flag of rx push mode
@@ -89,6 +90,7 @@ enum {
  */
 struct kernel_ethtool_ringparam {
 	u32	rx_buf_len;
+	u32	rx_buf_len_max;
 	u8	tcp_data_split;
 	u8	tx_push;
 	u8	rx_push;
diff --git a/include/uapi/linux/ethtool_netlink_generated.h b/include/uapi/linux/ethtool_netlink_generated.h
index e3b8813465d7..8b293d3499f1 100644
--- a/include/uapi/linux/ethtool_netlink_generated.h
+++ b/include/uapi/linux/ethtool_netlink_generated.h
@@ -192,6 +192,7 @@ enum {
 	ETHTOOL_A_RINGS_TX_PUSH_BUF_LEN_MAX,
 	ETHTOOL_A_RINGS_HDS_THRESH,
 	ETHTOOL_A_RINGS_HDS_THRESH_MAX,
+	ETHTOOL_A_RINGS_RX_BUF_LEN_MAX,
 
 	__ETHTOOL_A_RINGS_CNT,
 	ETHTOOL_A_RINGS_MAX = (__ETHTOOL_A_RINGS_CNT - 1)
diff --git a/net/ethtool/rings.c b/net/ethtool/rings.c
index aeedd5ec6b8c..5e872ceab5dd 100644
--- a/net/ethtool/rings.c
+++ b/net/ethtool/rings.c
@@ -105,6 +105,9 @@ static int rings_fill_reply(struct sk_buff *skb,
 			  ringparam->tx_pending)))  ||
 	    (kr->rx_buf_len &&
 	     (nla_put_u32(skb, ETHTOOL_A_RINGS_RX_BUF_LEN, kr->rx_buf_len))) ||
+	    (kr->rx_buf_len_max &&
+	     (nla_put_u32(skb, ETHTOOL_A_RINGS_RX_BUF_LEN_MAX,
+			  kr->rx_buf_len_max))) ||
 	    (kr->tcp_data_split &&
 	     (nla_put_u8(skb, ETHTOOL_A_RINGS_TCP_DATA_SPLIT,
 			 kr->tcp_data_split))) ||
@@ -281,6 +284,8 @@ ethnl_set_rings(struct ethnl_req_info *req_info, struct genl_info *info)
 		err_attr = tb[ETHTOOL_A_RINGS_TX];
 	else if (kernel_ringparam.hds_thresh > kernel_ringparam.hds_thresh_max)
 		err_attr = tb[ETHTOOL_A_RINGS_HDS_THRESH];
+	else if (kernel_ringparam.rx_buf_len > kernel_ringparam.rx_buf_len_max)
+		err_attr = tb[ETHTOOL_A_RINGS_RX_BUF_LEN];
 	else
 		err_attr = NULL;
 	if (err_attr) {
-- 
2.49.0

[RFC v2 04/24] net: use zero value to restore rx_buf_len to default

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

Distinguish between rx_buf_len being driver default vs user config.
Use 0 as a special value meaning "unset" or "restore driver default".
This will be necessary later on to configure it per-queue, but
the ability to restore defaults may be useful in itself.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 Documentation/networking/ethtool-netlink.rst              | 2 +-
 drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c | 3 +++
 include/linux/ethtool.h                                   | 1 +
 net/ethtool/rings.c                                       | 2 +-
 4 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index 05a7f6b3f945..83c6ac72549b 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -983,7 +983,7 @@ threshold value, header and data will be split.
 ``ETHTOOL_A_RINGS_RX_BUF_LEN`` controls the size of the buffers driver
 uses to receive packets. If the device uses different buffer pools for
 headers and payload (due to HDS, HW-GRO etc.) this setting must
-control the size of the payload buffers.
+control the size of the payload buffers. Setting to 0 restores driver default.
 
 CHANNELS_GET
 ============
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c
index 1c8a7ee2e459..1d120b7825de 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_ethtool.c
@@ -397,6 +397,9 @@ static int otx2_set_ringparam(struct net_device *netdev,
 	if (ring->rx_mini_pending || ring->rx_jumbo_pending)
 		return -EINVAL;
 
+	if (!rx_buf_len)
+		rx_buf_len = OTX2_DEFAULT_RBUF_LEN;
+
 	/* Hardware supports max size of 32k for a receive buffer
 	 * and 1536 is typical ethernet frame size.
 	 */
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 9267bac16195..e65f04a64266 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -77,6 +77,7 @@ enum {
 /**
  * struct kernel_ethtool_ringparam - RX/TX ring configuration
  * @rx_buf_len: Current length of buffers on the rx ring.
+ *		Setting to 0 means reset to driver default.
  * @rx_buf_len_max: Max length of buffers on the rx ring.
  * @tcp_data_split: Scatter packet headers and data to separate buffers
  * @tx_push: The flag of tx push mode
diff --git a/net/ethtool/rings.c b/net/ethtool/rings.c
index 5e872ceab5dd..628546a1827b 100644
--- a/net/ethtool/rings.c
+++ b/net/ethtool/rings.c
@@ -139,7 +139,7 @@ const struct nla_policy ethnl_rings_set_policy[] = {
 	[ETHTOOL_A_RINGS_RX_MINI]		= { .type = NLA_U32 },
 	[ETHTOOL_A_RINGS_RX_JUMBO]		= { .type = NLA_U32 },
 	[ETHTOOL_A_RINGS_TX]			= { .type = NLA_U32 },
-	[ETHTOOL_A_RINGS_RX_BUF_LEN]            = NLA_POLICY_MIN(NLA_U32, 1),
+	[ETHTOOL_A_RINGS_RX_BUF_LEN]            = { .type = NLA_U32 },
 	[ETHTOOL_A_RINGS_TCP_DATA_SPLIT]	=
 		NLA_POLICY_MAX(NLA_U8, ETHTOOL_TCP_DATA_SPLIT_ENABLED),
 	[ETHTOOL_A_RINGS_CQE_SIZE]		= NLA_POLICY_MIN(NLA_U32, 1),
-- 
2.49.0

[RFC v2 05/24] net: clarify the meaning of netdev_config members

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

hds_thresh and hds_config are both inside struct netdev_config
but have quite different semantics. hds_config is the user config
with ternary semantics (on/off/unset). hds_thresh is a straight
up value, populated by the driver at init and only modified by
user space. We don't expect the drivers to have to pick a special
hds_thresh value based on other configuration.

The two approaches have different advantages and downsides.
hds_thresh ("direct value") gives core easy access to current
device settings, but there's no way to express whether the value
comes from the user. It also requires the initialization by
the driver.

hds_config ("user config values") tells us what user wanted, but
doesn't give us the current value in the core.

Try to explain this a bit in the comments, so at we make a conscious
choice for new values which semantics we expect.

Move the init inside ethtool_ringparam_get_cfg() to reflect the semantics.
Commit 216a61d33c07 ("net: ethtool: fix ethtool_ringparam_get_cfg()
returns a hds_thresh value always as 0.") added the setting for the
benefit of netdevsim which doesn't touch the value at all on get.
Again, this is just to clarify the intention, shouldn't cause any
functional change.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[pavel: applied clarification on relationship b/w HDS thresh and config]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 include/net/netdev_queues.h | 20 ++++++++++++++++++--
 net/ethtool/common.c        |  3 ++-
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/include/net/netdev_queues.h b/include/net/netdev_queues.h
index 6e835972abd1..c8ce23e7c812 100644
--- a/include/net/netdev_queues.h
+++ b/include/net/netdev_queues.h
@@ -6,11 +6,27 @@
 
 /**
  * struct netdev_config - queue-related configuration for a netdev
- * @hds_thresh:		HDS Threshold value.
- * @hds_config:		HDS value from userspace.
  */
 struct netdev_config {
+	/* Direct value
+	 *
+	 * Driver default is expected to be fixed, and set in this struct
+	 * at init. From that point on user may change the value. There is
+	 * no explicit way to "unset" / restore driver default. Used only
+	 * when @hds_config is set.
+	 */
+	/** @hds_thresh: HDS Threshold value (ETHTOOL_A_RINGS_HDS_THRESH).
+	 */
 	u32	hds_thresh;
+
+	/* User config values
+	 *
+	 * Contain user configuration. If "set" driver must obey.
+	 * If "unset" driver is free to decide, and may change its choice
+	 * as other parameters change.
+	 */
+	/** @hds_config: HDS enabled (ETHTOOL_A_RINGS_TCP_DATA_SPLIT).
+	 */
 	u8	hds_config;
 };
 
diff --git a/net/ethtool/common.c b/net/ethtool/common.c
index 4f58648a27ad..faa95f91efad 100644
--- a/net/ethtool/common.c
+++ b/net/ethtool/common.c
@@ -882,12 +882,13 @@ void ethtool_ringparam_get_cfg(struct net_device *dev,
 	memset(param, 0, sizeof(*param));
 	memset(kparam, 0, sizeof(*kparam));
 
+	kparam->hds_thresh = dev->cfg->hds_thresh;
+
 	param->cmd = ETHTOOL_GRINGPARAM;
 	dev->ethtool_ops->get_ringparam(dev, param, kparam, extack);
 
 	/* Driver gives us current state, we want to return current config */
 	kparam->tcp_data_split = dev->cfg->hds_config;
-	kparam->hds_thresh = dev->cfg->hds_thresh;
 }
 
 static void ethtool_init_tsinfo(struct kernel_ethtool_ts_info *info)
-- 
2.49.0

[RFC v2 06/24] net: add rx_buf_len to netdev config

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

Add rx_buf_len to configuration maintained by the core.
Use "three-state" semantics where 0 means "driver default".

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 include/net/netdev_queues.h | 4 ++++
 net/ethtool/common.c        | 1 +
 net/ethtool/rings.c         | 2 ++
 3 files changed, 7 insertions(+)

diff --git a/include/net/netdev_queues.h b/include/net/netdev_queues.h
index c8ce23e7c812..8c21ea9b9515 100644
--- a/include/net/netdev_queues.h
+++ b/include/net/netdev_queues.h
@@ -25,6 +25,10 @@ struct netdev_config {
 	 * If "unset" driver is free to decide, and may change its choice
 	 * as other parameters change.
 	 */
+	/** @rx_buf_len: Size of buffers on the Rx ring
+	 *		 (ETHTOOL_A_RINGS_RX_BUF_LEN).
+	 */
+	u32	rx_buf_len;
 	/** @hds_config: HDS enabled (ETHTOOL_A_RINGS_TCP_DATA_SPLIT).
 	 */
 	u8	hds_config;
diff --git a/net/ethtool/common.c b/net/ethtool/common.c
index faa95f91efad..44fd27480756 100644
--- a/net/ethtool/common.c
+++ b/net/ethtool/common.c
@@ -889,6 +889,7 @@ void ethtool_ringparam_get_cfg(struct net_device *dev,
 
 	/* Driver gives us current state, we want to return current config */
 	kparam->tcp_data_split = dev->cfg->hds_config;
+	kparam->rx_buf_len = dev->cfg->rx_buf_len;
 }
 
 static void ethtool_init_tsinfo(struct kernel_ethtool_ts_info *info)
diff --git a/net/ethtool/rings.c b/net/ethtool/rings.c
index 628546a1827b..6a74e7e4064e 100644
--- a/net/ethtool/rings.c
+++ b/net/ethtool/rings.c
@@ -41,6 +41,7 @@ static int rings_prepare_data(const struct ethnl_req_info *req_base,
 		return ret;
 
 	data->kernel_ringparam.tcp_data_split = dev->cfg->hds_config;
+	data->kernel_ringparam.rx_buf_len = dev->cfg->rx_buf_len;
 	data->kernel_ringparam.hds_thresh = dev->cfg->hds_thresh;
 
 	dev->ethtool_ops->get_ringparam(dev, &data->ringparam,
@@ -302,6 +303,7 @@ ethnl_set_rings(struct ethnl_req_info *req_info, struct genl_info *info)
 		return -EINVAL;
 	}
 
+	dev->cfg_pending->rx_buf_len = kernel_ringparam.rx_buf_len;
 	dev->cfg_pending->hds_config = kernel_ringparam.tcp_data_split;
 	dev->cfg_pending->hds_thresh = kernel_ringparam.hds_thresh;
 
-- 
2.49.0

[RFC v2 07/24] eth: bnxt: read the page size from the adapter struct

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

Switch from using a constant to storing the BNXT_RX_PAGE_SIZE
inside struct bnxt. This will allow configuring the page size
at runtime in subsequent patches.

The MSS size calculation for older chip continues to use the constant.
I'm intending to support the configuration only on more recent HW,
looks like on older chips setting this per queue won't work,
and that's the ultimate goal.

This patch should not change the current behavior as value
read from the struct will always be BNXT_RX_PAGE_SIZE at this stage.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c     | 27 ++++++++++---------
 drivers/net/ethernet/broadcom/bnxt/bnxt.h     |  1 +
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c |  4 +--
 3 files changed, 17 insertions(+), 15 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 5578ddcb465d..7d35e9a8869b 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -900,7 +900,7 @@ static void bnxt_tx_int(struct bnxt *bp, struct bnxt_napi *bnapi, int budget)
 
 static bool bnxt_separate_head_pool(struct bnxt_rx_ring_info *rxr)
 {
-	return rxr->need_head_pool || PAGE_SIZE > BNXT_RX_PAGE_SIZE;
+	return rxr->need_head_pool || PAGE_SIZE > rxr->bnapi->bp->rx_page_size;
 }
 
 static struct page *__bnxt_alloc_rx_page(struct bnxt *bp, dma_addr_t *mapping,
@@ -910,9 +910,9 @@ static struct page *__bnxt_alloc_rx_page(struct bnxt *bp, dma_addr_t *mapping,
 {
 	struct page *page;
 
-	if (PAGE_SIZE > BNXT_RX_PAGE_SIZE) {
+	if (PAGE_SIZE > bp->rx_page_size) {
 		page = page_pool_dev_alloc_frag(rxr->page_pool, offset,
-						BNXT_RX_PAGE_SIZE);
+						bp->rx_page_size);
 	} else {
 		page = page_pool_dev_alloc_pages(rxr->page_pool);
 		*offset = 0;
@@ -1144,9 +1144,9 @@ static struct sk_buff *bnxt_rx_multi_page_skb(struct bnxt *bp,
 		return NULL;
 	}
 	dma_addr -= bp->rx_dma_offset;
-	dma_sync_single_for_cpu(&bp->pdev->dev, dma_addr, BNXT_RX_PAGE_SIZE,
+	dma_sync_single_for_cpu(&bp->pdev->dev, dma_addr, bp->rx_page_size,
 				bp->rx_dir);
-	skb = napi_build_skb(data_ptr - bp->rx_offset, BNXT_RX_PAGE_SIZE);
+	skb = napi_build_skb(data_ptr - bp->rx_offset, bp->rx_page_size);
 	if (!skb) {
 		page_pool_recycle_direct(rxr->page_pool, page);
 		return NULL;
@@ -1178,7 +1178,7 @@ static struct sk_buff *bnxt_rx_page_skb(struct bnxt *bp,
 		return NULL;
 	}
 	dma_addr -= bp->rx_dma_offset;
-	dma_sync_single_for_cpu(&bp->pdev->dev, dma_addr, BNXT_RX_PAGE_SIZE,
+	dma_sync_single_for_cpu(&bp->pdev->dev, dma_addr, bp->rx_page_size,
 				bp->rx_dir);
 
 	if (unlikely(!payload))
@@ -1192,7 +1192,7 @@ static struct sk_buff *bnxt_rx_page_skb(struct bnxt *bp,
 
 	skb_mark_for_recycle(skb);
 	off = (void *)data_ptr - page_address(page);
-	skb_add_rx_frag(skb, 0, page, off, len, BNXT_RX_PAGE_SIZE);
+	skb_add_rx_frag(skb, 0, page, off, len, bp->rx_page_size);
 	memcpy(skb->data - NET_IP_ALIGN, data_ptr - NET_IP_ALIGN,
 	       payload + NET_IP_ALIGN);
 
@@ -1277,7 +1277,7 @@ static u32 __bnxt_rx_agg_netmems(struct bnxt *bp,
 		if (skb) {
 			skb_add_rx_frag_netmem(skb, i, cons_rx_buf->netmem,
 					       cons_rx_buf->offset,
-					       frag_len, BNXT_RX_PAGE_SIZE);
+					       frag_len, bp->rx_page_size);
 		} else {
 			skb_frag_t *frag = &shinfo->frags[i];
 
@@ -1302,7 +1302,7 @@ static u32 __bnxt_rx_agg_netmems(struct bnxt *bp,
 			if (skb) {
 				skb->len -= frag_len;
 				skb->data_len -= frag_len;
-				skb->truesize -= BNXT_RX_PAGE_SIZE;
+				skb->truesize -= bp->rx_page_size;
 			}
 
 			--shinfo->nr_frags;
@@ -1317,7 +1317,7 @@ static u32 __bnxt_rx_agg_netmems(struct bnxt *bp,
 		}
 
 		page_pool_dma_sync_netmem_for_cpu(rxr->page_pool, netmem, 0,
-						  BNXT_RX_PAGE_SIZE);
+						  bp->rx_page_size);
 
 		total_frag_len += frag_len;
 		prod = NEXT_RX_AGG(prod);
@@ -4460,7 +4460,7 @@ static void bnxt_init_one_rx_agg_ring_rxbd(struct bnxt *bp,
 	ring = &rxr->rx_agg_ring_struct;
 	ring->fw_ring_id = INVALID_HW_RING_ID;
 	if ((bp->flags & BNXT_FLAG_AGG_RINGS)) {
-		type = ((u32)BNXT_RX_PAGE_SIZE << RX_BD_LEN_SHIFT) |
+		type = ((u32)bp->rx_page_size << RX_BD_LEN_SHIFT) |
 			RX_BD_TYPE_RX_AGG_BD | RX_BD_FLAGS_SOP;
 
 		bnxt_init_rxbd_pages(ring, type);
@@ -4722,7 +4722,7 @@ void bnxt_set_ring_params(struct bnxt *bp)
 	bp->rx_agg_nr_pages = 0;
 
 	if (bp->flags & BNXT_FLAG_TPA || bp->flags & BNXT_FLAG_HDS)
-		agg_factor = min_t(u32, 4, 65536 / BNXT_RX_PAGE_SIZE);
+		agg_factor = min_t(u32, 4, 65536 / bp->rx_page_size);
 
 	bp->flags &= ~BNXT_FLAG_JUMBO;
 	if (rx_space > PAGE_SIZE && !(bp->flags & BNXT_FLAG_NO_AGG_RINGS)) {
@@ -7034,7 +7034,7 @@ static void bnxt_set_rx_ring_params_p5(struct bnxt *bp, u32 ring_type,
 	if (ring_type == HWRM_RING_ALLOC_AGG) {
 		req->ring_type = RING_ALLOC_REQ_RING_TYPE_RX_AGG;
 		req->rx_ring_id = cpu_to_le16(grp_info->rx_fw_ring_id);
-		req->rx_buf_size = cpu_to_le16(BNXT_RX_PAGE_SIZE);
+		req->rx_buf_size = cpu_to_le16(bp->rx_page_size);
 		enables |= RING_ALLOC_REQ_ENABLES_RX_RING_ID_VALID;
 	} else {
 		req->rx_buf_size = cpu_to_le16(bp->rx_buf_use_size);
@@ -16563,6 +16563,7 @@ static int bnxt_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	bp = netdev_priv(dev);
 	bp->board_idx = ent->driver_data;
 	bp->msg_enable = BNXT_DEF_MSG_ENABLE;
+	bp->rx_page_size = BNXT_RX_PAGE_SIZE;
 	bnxt_set_max_func_irqs(bp, max_irqs);
 
 	if (bnxt_vf_pciid(bp->board_idx))
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index fda0d3cc6227..ac841d02d7ad 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -2358,6 +2358,7 @@ struct bnxt {
 	u16			max_tpa;
 	u32			rx_buf_size;
 	u32			rx_buf_use_size;	/* useable size */
+	u16			rx_page_size;
 	u16			rx_offset;
 	u16			rx_dma_offset;
 	enum dma_data_direction	rx_dir;
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
index 58d579dca3f1..41d3ba56ba41 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
@@ -183,7 +183,7 @@ void bnxt_xdp_buff_init(struct bnxt *bp, struct bnxt_rx_ring_info *rxr,
 			u16 cons, u8 *data_ptr, unsigned int len,
 			struct xdp_buff *xdp)
 {
-	u32 buflen = BNXT_RX_PAGE_SIZE;
+	u32 buflen = bp->rx_page_size;
 	struct bnxt_sw_rx_bd *rx_buf;
 	struct pci_dev *pdev;
 	dma_addr_t mapping;
@@ -470,7 +470,7 @@ bnxt_xdp_build_skb(struct bnxt *bp, struct sk_buff *skb, u8 num_frags,
 
 	xdp_update_skb_shared_info(skb, num_frags,
 				   sinfo->xdp_frags_size,
-				   BNXT_RX_PAGE_SIZE * num_frags,
+				   bp->rx_page_size * num_frags,
 				   xdp_buff_is_frag_pfmemalloc(xdp));
 	return skb;
 }
-- 
2.49.0

[RFC v2 08/24] eth: bnxt: set page pool page order based on rx_page_size

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

If user decides to increase the buffer size for agg ring
we need to ask the page pool for higher order pages.
There is no need to use larger pages for header frags,
if user increase the size of agg ring buffers switch
to separate header page automatically.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[pavel: calculate adjust max_len]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 7d35e9a8869b..869c15d4dc34 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -3818,12 +3818,14 @@ static int bnxt_alloc_rx_page_pool(struct bnxt *bp,
 	pp.pool_size = bp->rx_agg_ring_size / agg_size_fac;
 	if (BNXT_RX_PAGE_MODE(bp))
 		pp.pool_size += bp->rx_ring_size / rx_size_fac;
+
+	pp.order = get_order(bp->rx_page_size);
 	pp.nid = numa_node;
 	pp.napi = &rxr->bnapi->napi;
 	pp.netdev = bp->dev;
 	pp.dev = &bp->pdev->dev;
 	pp.dma_dir = bp->rx_dir;
-	pp.max_len = PAGE_SIZE;
+	pp.max_len = PAGE_SIZE << pp.order;
 	pp.flags = PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV |
 		   PP_FLAG_ALLOW_UNREADABLE_NETMEM;
 	pp.queue_idx = rxr->bnapi->index;
@@ -3834,7 +3836,10 @@ static int bnxt_alloc_rx_page_pool(struct bnxt *bp,
 	rxr->page_pool = pool;
 
 	rxr->need_head_pool = page_pool_is_unreadable(pool);
+	rxr->need_head_pool |= !!pp.order;
 	if (bnxt_separate_head_pool(rxr)) {
+		pp.order = 0;
+		pp.max_len = PAGE_SIZE;
 		pp.pool_size = min(bp->rx_ring_size / rx_size_fac, 1024);
 		pp.flags = PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV;
 		pool = page_pool_create(&pp);
-- 
2.49.0

[RFC v2 09/24] eth: bnxt: support setting size of agg buffers via ethtool

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

bnxt seems to be able to aggregate data up to 32kB without any issue.
The driver is already capable of doing this for systems with higher
order pages. While for systems with 4k pages we historically preferred
to stick to small buffers because they are easier to allocate, the
zero-copy APIs remove the allocation problem. The ZC mem is
pre-allocated and fixed size.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.h     |  3 ++-
 .../net/ethernet/broadcom/bnxt/bnxt_ethtool.c | 21 ++++++++++++++++++-
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index ac841d02d7ad..56aafae568f8 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -758,7 +758,8 @@ struct nqe_cn {
 #define BNXT_RX_PAGE_SHIFT PAGE_SHIFT
 #endif
 
-#define BNXT_RX_PAGE_SIZE (1 << BNXT_RX_PAGE_SHIFT)
+#define BNXT_MAX_RX_PAGE_SIZE	(1 << 15)
+#define BNXT_RX_PAGE_SIZE	(1 << BNXT_RX_PAGE_SHIFT)
 
 #define BNXT_MAX_MTU		9500
 
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
index 1b37612b1c01..2e130eeeabe5 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -835,6 +835,8 @@ static void bnxt_get_ringparam(struct net_device *dev,
 	ering->rx_jumbo_pending = bp->rx_agg_ring_size;
 	ering->tx_pending = bp->tx_ring_size;
 
+	kernel_ering->rx_buf_len_max = BNXT_MAX_RX_PAGE_SIZE;
+	kernel_ering->rx_buf_len = bp->rx_page_size;
 	kernel_ering->hds_thresh_max = BNXT_HDS_THRESHOLD_MAX;
 }
 
@@ -862,6 +864,21 @@ static int bnxt_set_ringparam(struct net_device *dev,
 		return -EINVAL;
 	}
 
+	if (!kernel_ering->rx_buf_len)	/* Zero means restore default */
+		kernel_ering->rx_buf_len = BNXT_RX_PAGE_SIZE;
+
+	if (kernel_ering->rx_buf_len != bp->rx_page_size &&
+	    !(bp->flags & BNXT_FLAG_CHIP_P5_PLUS)) {
+		NL_SET_ERR_MSG_MOD(extack, "changing rx-buf-len not supported");
+		return -EINVAL;
+	}
+	if (!is_power_of_2(kernel_ering->rx_buf_len) ||
+	    kernel_ering->rx_buf_len < BNXT_RX_PAGE_SIZE ||
+	    kernel_ering->rx_buf_len > BNXT_MAX_RX_PAGE_SIZE) {
+		NL_SET_ERR_MSG_MOD(extack, "rx-buf-len out of range, or not power of 2");
+		return -ERANGE;
+	}
+
 	if (netif_running(dev))
 		bnxt_close_nic(bp, false, false);
 
@@ -874,6 +891,7 @@ static int bnxt_set_ringparam(struct net_device *dev,
 
 	bp->rx_ring_size = ering->rx_pending;
 	bp->tx_ring_size = ering->tx_pending;
+	bp->rx_page_size = kernel_ering->rx_buf_len;
 	bnxt_set_ring_params(bp);
 
 	if (netif_running(dev))
@@ -5489,7 +5507,8 @@ const struct ethtool_ops bnxt_ethtool_ops = {
 				     ETHTOOL_COALESCE_STATS_BLOCK_USECS |
 				     ETHTOOL_COALESCE_USE_ADAPTIVE_RX |
 				     ETHTOOL_COALESCE_USE_CQE,
-	.supported_ring_params	= ETHTOOL_RING_USE_TCP_DATA_SPLIT |
+	.supported_ring_params	= ETHTOOL_RING_USE_RX_BUF_LEN |
+				  ETHTOOL_RING_USE_TCP_DATA_SPLIT |
 				  ETHTOOL_RING_USE_HDS_THRS,
 	.get_link_ksettings	= bnxt_get_link_ksettings,
 	.set_link_ksettings	= bnxt_set_link_ksettings,
-- 
2.49.0

[RFC v2 10/24] net: move netdev_config manipulation to dedicated helpers

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

netdev_config manipulation will become slightly more complicated
soon and we will need to call if from ethtool as well as queue API.
Encapsulate the logic into helper functions.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 net/core/Makefile        |  2 +-
 net/core/dev.c           |  7 ++-----
 net/core/dev.h           |  5 +++++
 net/core/netdev_config.c | 43 ++++++++++++++++++++++++++++++++++++++++
 net/ethtool/netlink.c    | 14 ++++++-------
 5 files changed, 57 insertions(+), 14 deletions(-)
 create mode 100644 net/core/netdev_config.c

diff --git a/net/core/Makefile b/net/core/Makefile
index b2a76ce33932..4db487396094 100644
--- a/net/core/Makefile
+++ b/net/core/Makefile
@@ -19,7 +19,7 @@ obj-$(CONFIG_NETDEV_ADDR_LIST_TEST) += dev_addr_lists_test.o
 
 obj-y += net-sysfs.o
 obj-y += hotdata.o
-obj-y += netdev_rx_queue.o
+obj-y += netdev_config.o netdev_rx_queue.o
 obj-$(CONFIG_PAGE_POOL) += page_pool.o page_pool_user.o
 obj-$(CONFIG_PROC_FS) += net-procfs.o
 obj-$(CONFIG_NET_PKTGEN) += pktgen.o
diff --git a/net/core/dev.c b/net/core/dev.c
index 1c6e755841ce..8e9af8469421 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -11875,10 +11875,8 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
 	if (!dev->ethtool)
 		goto free_all;
 
-	dev->cfg = kzalloc(sizeof(*dev->cfg), GFP_KERNEL_ACCOUNT);
-	if (!dev->cfg)
+	if (netdev_alloc_config(dev))
 		goto free_all;
-	dev->cfg_pending = dev->cfg;
 
 	napi_config_sz = array_size(maxqs, sizeof(*dev->napi_config));
 	dev->napi_config = kvzalloc(napi_config_sz, GFP_KERNEL_ACCOUNT);
@@ -11948,8 +11946,7 @@ void free_netdev(struct net_device *dev)
 		return;
 	}
 
-	WARN_ON(dev->cfg != dev->cfg_pending);
-	kfree(dev->cfg);
+	netdev_free_config(dev);
 	kfree(dev->ethtool);
 	netif_free_tx_queues(dev);
 	netif_free_rx_queues(dev);
diff --git a/net/core/dev.h b/net/core/dev.h
index ab69edc0c3e3..5c9f43280eca 100644
--- a/net/core/dev.h
+++ b/net/core/dev.h
@@ -92,6 +92,11 @@ extern struct rw_semaphore dev_addr_sem;
 extern struct list_head net_todo_list;
 void netdev_run_todo(void);
 
+int netdev_alloc_config(struct net_device *dev);
+void __netdev_free_config(struct netdev_config *cfg);
+void netdev_free_config(struct net_device *dev);
+int netdev_reconfig_start(struct net_device *dev);
+
 /* netdev management, shared between various uAPI entry points */
 struct netdev_name_node {
 	struct hlist_node hlist;
diff --git a/net/core/netdev_config.c b/net/core/netdev_config.c
new file mode 100644
index 000000000000..270b7f10a192
--- /dev/null
+++ b/net/core/netdev_config.c
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/netdevice.h>
+#include <net/netdev_queues.h>
+
+#include "dev.h"
+
+int netdev_alloc_config(struct net_device *dev)
+{
+	struct netdev_config *cfg;
+
+	cfg = kzalloc(sizeof(*dev->cfg), GFP_KERNEL_ACCOUNT);
+	if (!cfg)
+		return -ENOMEM;
+
+	dev->cfg = cfg;
+	dev->cfg_pending = cfg;
+	return 0;
+}
+
+void __netdev_free_config(struct netdev_config *cfg)
+{
+	kfree(cfg);
+}
+
+void netdev_free_config(struct net_device *dev)
+{
+	WARN_ON(dev->cfg != dev->cfg_pending);
+	__netdev_free_config(dev->cfg);
+}
+
+int netdev_reconfig_start(struct net_device *dev)
+{
+	struct netdev_config *cfg;
+
+	WARN_ON(dev->cfg != dev->cfg_pending);
+	cfg = kmemdup(dev->cfg, sizeof(*dev->cfg), GFP_KERNEL_ACCOUNT);
+	if (!cfg)
+		return -ENOMEM;
+
+	dev->cfg_pending = cfg;
+	return 0;
+}
diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index 2f813f25f07e..d376d3043177 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -6,6 +6,7 @@
 #include <linux/ethtool_netlink.h>
 #include <linux/phy_link_topology.h>
 #include <linux/pm_runtime.h>
+#include "../core/dev.h"
 #include "netlink.h"
 #include "module_fw.h"
 
@@ -906,12 +907,9 @@ static int ethnl_default_set_doit(struct sk_buff *skb, struct genl_info *info)
 
 	rtnl_lock();
 	netdev_lock_ops(dev);
-	dev->cfg_pending = kmemdup(dev->cfg, sizeof(*dev->cfg),
-				   GFP_KERNEL_ACCOUNT);
-	if (!dev->cfg_pending) {
-		ret = -ENOMEM;
-		goto out_tie_cfg;
-	}
+	ret = netdev_reconfig_start(dev);
+	if (ret)
+		goto out_unlock;
 
 	ret = ethnl_ops_begin(dev);
 	if (ret < 0)
@@ -930,9 +928,9 @@ static int ethnl_default_set_doit(struct sk_buff *skb, struct genl_info *info)
 out_ops:
 	ethnl_ops_complete(dev);
 out_free_cfg:
-	kfree(dev->cfg_pending);
-out_tie_cfg:
+	__netdev_free_config(dev->cfg_pending);
 	dev->cfg_pending = dev->cfg;
+out_unlock:
 	netdev_unlock_ops(dev);
 	rtnl_unlock();
 out_dev:
-- 
2.49.0

[RFC v2 11/24] net: reduce indent of struct netdev_queue_mgmt_ops members

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

Trivial change, reduce the indent. I think the original is copied
from real NDOs. It's unnecessarily deep, makes passing struct args
problematic.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 include/net/netdev_queues.h | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/include/net/netdev_queues.h b/include/net/netdev_queues.h
index 8c21ea9b9515..d73f9023c96f 100644
--- a/include/net/netdev_queues.h
+++ b/include/net/netdev_queues.h
@@ -152,18 +152,18 @@ void netdev_stat_queue_sum(struct net_device *netdev,
  * be called for an interface which is open.
  */
 struct netdev_queue_mgmt_ops {
-	size_t			ndo_queue_mem_size;
-	int			(*ndo_queue_mem_alloc)(struct net_device *dev,
-						       void *per_queue_mem,
-						       int idx);
-	void			(*ndo_queue_mem_free)(struct net_device *dev,
-						      void *per_queue_mem);
-	int			(*ndo_queue_start)(struct net_device *dev,
-						   void *per_queue_mem,
-						   int idx);
-	int			(*ndo_queue_stop)(struct net_device *dev,
-						  void *per_queue_mem,
-						  int idx);
+	size_t	ndo_queue_mem_size;
+	int	(*ndo_queue_mem_alloc)(struct net_device *dev,
+				       void *per_queue_mem,
+				       int idx);
+	void	(*ndo_queue_mem_free)(struct net_device *dev,
+				      void *per_queue_mem);
+	int	(*ndo_queue_start)(struct net_device *dev,
+				   void *per_queue_mem,
+				   int idx);
+	int	(*ndo_queue_stop)(struct net_device *dev,
+				  void *per_queue_mem,
+				  int idx);
 };
 
 /**
-- 
2.49.0

[RFC v2 12/24] net: allocate per-queue config structs and pass them thru the queue API

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

Create an array of config structs to store per-queue config.
Pass these structs in the queue API. Drivers can also retrieve
the config for a single queue calling netdev_queue_config()
directly.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[pavel: patch up mlx callbacks with unused qcfg]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c     |  8 ++-
 drivers/net/ethernet/google/gve/gve_main.c    |  9 ++-
 .../net/ethernet/mellanox/mlx5/core/en_main.c |  9 +--
 drivers/net/netdevsim/netdev.c                |  6 +-
 include/net/netdev_queues.h                   | 19 ++++++
 net/core/dev.h                                |  3 +
 net/core/netdev_config.c                      | 58 +++++++++++++++++++
 net/core/netdev_rx_queue.c                    | 11 +++-
 8 files changed, 109 insertions(+), 14 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 869c15d4dc34..96b6fa696247 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -15812,7 +15812,9 @@ static const struct netdev_stat_ops bnxt_stat_ops = {
 	.get_base_stats		= bnxt_get_base_stats,
 };
 
-static int bnxt_queue_mem_alloc(struct net_device *dev, void *qmem, int idx)
+static int bnxt_queue_mem_alloc(struct net_device *dev,
+				struct netdev_queue_config *qcfg,
+				void *qmem, int idx)
 {
 	struct bnxt_rx_ring_info *rxr, *clone;
 	struct bnxt *bp = netdev_priv(dev);
@@ -15980,7 +15982,9 @@ static void bnxt_copy_rx_ring(struct bnxt *bp,
 	dst->rx_agg_bmap = src->rx_agg_bmap;
 }
 
-static int bnxt_queue_start(struct net_device *dev, void *qmem, int idx)
+static int bnxt_queue_start(struct net_device *dev,
+			    struct netdev_queue_config *qcfg,
+			    void *qmem, int idx)
 {
 	struct bnxt *bp = netdev_priv(dev);
 	struct bnxt_rx_ring_info *rxr, *clone;
diff --git a/drivers/net/ethernet/google/gve/gve_main.c b/drivers/net/ethernet/google/gve/gve_main.c
index 1f411d7c4373..f40edab616d8 100644
--- a/drivers/net/ethernet/google/gve/gve_main.c
+++ b/drivers/net/ethernet/google/gve/gve_main.c
@@ -2580,8 +2580,9 @@ static void gve_rx_queue_mem_free(struct net_device *dev, void *per_q_mem)
 		gve_rx_free_ring_dqo(priv, gve_per_q_mem, &cfg);
 }
 
-static int gve_rx_queue_mem_alloc(struct net_device *dev, void *per_q_mem,
-				  int idx)
+static int gve_rx_queue_mem_alloc(struct net_device *dev,
+				  struct netdev_queue_config *qcfg,
+				  void *per_q_mem, int idx)
 {
 	struct gve_priv *priv = netdev_priv(dev);
 	struct gve_rx_alloc_rings_cfg cfg = {0};
@@ -2602,7 +2603,9 @@ static int gve_rx_queue_mem_alloc(struct net_device *dev, void *per_q_mem,
 	return err;
 }
 
-static int gve_rx_queue_start(struct net_device *dev, void *per_q_mem, int idx)
+static int gve_rx_queue_start(struct net_device *dev,
+			      struct netdev_queue_config *qcfg,
+			      void *per_q_mem, int idx)
 {
 	struct gve_priv *priv = netdev_priv(dev);
 	struct gve_rx_ring *gve_per_q_mem;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 21bb88c5d3dc..83264c17a4f7 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -5541,8 +5541,9 @@ struct mlx5_qmgmt_data {
 	struct mlx5e_channel_param cparam;
 };
 
-static int mlx5e_queue_mem_alloc(struct net_device *dev, void *newq,
-				 int queue_index)
+static int mlx5e_queue_mem_alloc(struct net_device *dev,
+				 struct netdev_queue_config *qcfg,
+				 void *newq, int queue_index)
 {
 	struct mlx5_qmgmt_data *new = (struct mlx5_qmgmt_data *)newq;
 	struct mlx5e_priv *priv = netdev_priv(dev);
@@ -5603,8 +5604,8 @@ static int mlx5e_queue_stop(struct net_device *dev, void *oldq, int queue_index)
 	return 0;
 }
 
-static int mlx5e_queue_start(struct net_device *dev, void *newq,
-			     int queue_index)
+static int mlx5e_queue_start(struct net_device *dev, struct netdev_queue_config *qcfg,
+			     void *newq, int queue_index)
 {
 	struct mlx5_qmgmt_data *new = (struct mlx5_qmgmt_data *)newq;
 	struct mlx5e_priv *priv = netdev_priv(dev);
diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c
index 39fe28af48b9..46cdf31f0354 100644
--- a/drivers/net/netdevsim/netdev.c
+++ b/drivers/net/netdevsim/netdev.c
@@ -729,7 +729,8 @@ struct nsim_queue_mem {
 };
 
 static int
-nsim_queue_mem_alloc(struct net_device *dev, void *per_queue_mem, int idx)
+nsim_queue_mem_alloc(struct net_device *dev, struct netdev_queue_config *qcfg,
+		     void *per_queue_mem, int idx)
 {
 	struct nsim_queue_mem *qmem = per_queue_mem;
 	struct netdevsim *ns = netdev_priv(dev);
@@ -778,7 +779,8 @@ static void nsim_queue_mem_free(struct net_device *dev, void *per_queue_mem)
 }
 
 static int
-nsim_queue_start(struct net_device *dev, void *per_queue_mem, int idx)
+nsim_queue_start(struct net_device *dev, struct netdev_queue_config *qcfg,
+		 void *per_queue_mem, int idx)
 {
 	struct nsim_queue_mem *qmem = per_queue_mem;
 	struct netdevsim *ns = netdev_priv(dev);
diff --git a/include/net/netdev_queues.h b/include/net/netdev_queues.h
index d73f9023c96f..b850cff71d12 100644
--- a/include/net/netdev_queues.h
+++ b/include/net/netdev_queues.h
@@ -32,6 +32,13 @@ struct netdev_config {
 	/** @hds_config: HDS enabled (ETHTOOL_A_RINGS_TCP_DATA_SPLIT).
 	 */
 	u8	hds_config;
+
+	/** @qcfg: per-queue configuration */
+	struct netdev_queue_config *qcfg;
+};
+
+/* Same semantics as fields in struct netdev_config */
+struct netdev_queue_config {
 };
 
 /* See the netdev.yaml spec for definition of each statistic */
@@ -136,6 +143,10 @@ void netdev_stat_queue_sum(struct net_device *netdev,
  *
  * @ndo_queue_mem_size: Size of the struct that describes a queue's memory.
  *
+ * @ndo_queue_cfg_defaults: (Optional) Populate queue config struct with
+ *			defaults. Queue config structs are passed to this
+ *			helper before the user-requested settings are applied.
+ *
  * @ndo_queue_mem_alloc: Allocate memory for an RX queue at the specified index.
  *			 The new memory is written at the specified address.
  *
@@ -153,12 +164,17 @@ void netdev_stat_queue_sum(struct net_device *netdev,
  */
 struct netdev_queue_mgmt_ops {
 	size_t	ndo_queue_mem_size;
+	void	(*ndo_queue_cfg_defaults)(struct net_device *dev,
+					  int idx,
+					  struct netdev_queue_config *qcfg);
 	int	(*ndo_queue_mem_alloc)(struct net_device *dev,
+				       struct netdev_queue_config *qcfg,
 				       void *per_queue_mem,
 				       int idx);
 	void	(*ndo_queue_mem_free)(struct net_device *dev,
 				      void *per_queue_mem);
 	int	(*ndo_queue_start)(struct net_device *dev,
+				   struct netdev_queue_config *qcfg,
 				   void *per_queue_mem,
 				   int idx);
 	int	(*ndo_queue_stop)(struct net_device *dev,
@@ -166,6 +182,9 @@ struct netdev_queue_mgmt_ops {
 				  int idx);
 };
 
+void netdev_queue_config(struct net_device *dev, int rxq,
+			 struct netdev_queue_config *qcfg);
+
 /**
  * DOC: Lockless queue stopping / waking helpers.
  *
diff --git a/net/core/dev.h b/net/core/dev.h
index 5c9f43280eca..5fdcf97149f9 100644
--- a/net/core/dev.h
+++ b/net/core/dev.h
@@ -9,6 +9,7 @@
 #include <net/netdev_lock.h>
 
 struct net;
+struct netdev_queue_config;
 struct netlink_ext_ack;
 struct cpumask;
 
@@ -96,6 +97,8 @@ int netdev_alloc_config(struct net_device *dev);
 void __netdev_free_config(struct netdev_config *cfg);
 void netdev_free_config(struct net_device *dev);
 int netdev_reconfig_start(struct net_device *dev);
+void __netdev_queue_config(struct net_device *dev, int rxq,
+			   struct netdev_queue_config *qcfg, bool pending);
 
 /* netdev management, shared between various uAPI entry points */
 struct netdev_name_node {
diff --git a/net/core/netdev_config.c b/net/core/netdev_config.c
index 270b7f10a192..bad2d53522f0 100644
--- a/net/core/netdev_config.c
+++ b/net/core/netdev_config.c
@@ -8,18 +8,29 @@
 int netdev_alloc_config(struct net_device *dev)
 {
 	struct netdev_config *cfg;
+	unsigned int maxqs;
 
 	cfg = kzalloc(sizeof(*dev->cfg), GFP_KERNEL_ACCOUNT);
 	if (!cfg)
 		return -ENOMEM;
 
+	maxqs = max(dev->num_rx_queues, dev->num_tx_queues);
+	cfg->qcfg = kcalloc(maxqs, sizeof(*cfg->qcfg), GFP_KERNEL_ACCOUNT);
+	if (!cfg->qcfg)
+		goto err_free_cfg;
+
 	dev->cfg = cfg;
 	dev->cfg_pending = cfg;
 	return 0;
+
+err_free_cfg:
+	kfree(cfg);
+	return -ENOMEM;
 }
 
 void __netdev_free_config(struct netdev_config *cfg)
 {
+	kfree(cfg->qcfg);
 	kfree(cfg);
 }
 
@@ -32,12 +43,59 @@ void netdev_free_config(struct net_device *dev)
 int netdev_reconfig_start(struct net_device *dev)
 {
 	struct netdev_config *cfg;
+	unsigned int maxqs;
 
 	WARN_ON(dev->cfg != dev->cfg_pending);
 	cfg = kmemdup(dev->cfg, sizeof(*dev->cfg), GFP_KERNEL_ACCOUNT);
 	if (!cfg)
 		return -ENOMEM;
 
+	maxqs = max(dev->num_rx_queues, dev->num_tx_queues);
+	cfg->qcfg = kmemdup_array(dev->cfg->qcfg, maxqs, sizeof(*cfg->qcfg),
+				  GFP_KERNEL_ACCOUNT);
+	if (!cfg->qcfg)
+		goto err_free_cfg;
+
 	dev->cfg_pending = cfg;
 	return 0;
+
+err_free_cfg:
+	kfree(cfg);
+	return -ENOMEM;
+}
+
+void __netdev_queue_config(struct net_device *dev, int rxq,
+			   struct netdev_queue_config *qcfg, bool pending)
+{
+	memset(qcfg, 0, sizeof(*qcfg));
+
+	/* Get defaults from the driver, in case user config not set */
+	if (dev->queue_mgmt_ops->ndo_queue_cfg_defaults)
+		dev->queue_mgmt_ops->ndo_queue_cfg_defaults(dev, rxq, qcfg);
+}
+
+/**
+ * netdev_queue_config() - get configuration for a given queue
+ * @dev:  net_device instance
+ * @rxq:  index of the queue of interest
+ * @qcfg: queue configuration struct (output)
+ *
+ * Render the configuration for a given queue. This helper should be used
+ * by drivers which support queue configuration to retrieve config for
+ * a particular queue.
+ *
+ * @qcfg is an output parameter and is always fully initialized by this
+ * function. Some values may not be set by the user, drivers may either
+ * deal with the "unset" values in @qcfg, or provide the callback
+ * to populate defaults in queue_management_ops.
+ *
+ * Note that this helper returns pending config, as it is expected that
+ * "old" queues are retained until config is successful so they can
+ * be restored directly without asking for the config.
+ */
+void netdev_queue_config(struct net_device *dev, int rxq,
+			 struct netdev_queue_config *qcfg)
+{
+	__netdev_queue_config(dev, rxq, qcfg, true);
 }
+EXPORT_SYMBOL(netdev_queue_config);
diff --git a/net/core/netdev_rx_queue.c b/net/core/netdev_rx_queue.c
index 3bf1151d8061..fb87ce219a8a 100644
--- a/net/core/netdev_rx_queue.c
+++ b/net/core/netdev_rx_queue.c
@@ -7,12 +7,14 @@
 #include <net/netdev_rx_queue.h>
 #include <net/page_pool/memory_provider.h>
 
+#include "dev.h"
 #include "page_pool_priv.h"
 
 int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx)
 {
 	struct netdev_rx_queue *rxq = __netif_get_rx_queue(dev, rxq_idx);
 	const struct netdev_queue_mgmt_ops *qops = dev->queue_mgmt_ops;
+	struct netdev_queue_config qcfg;
 	void *new_mem, *old_mem;
 	int err;
 
@@ -32,7 +34,9 @@ int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx)
 		goto err_free_new_mem;
 	}
 
-	err = qops->ndo_queue_mem_alloc(dev, new_mem, rxq_idx);
+	netdev_queue_config(dev, rxq_idx, &qcfg);
+
+	err = qops->ndo_queue_mem_alloc(dev, &qcfg, new_mem, rxq_idx);
 	if (err)
 		goto err_free_old_mem;
 
@@ -45,7 +49,7 @@ int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx)
 		if (err)
 			goto err_free_new_queue_mem;
 
-		err = qops->ndo_queue_start(dev, new_mem, rxq_idx);
+		err = qops->ndo_queue_start(dev, &qcfg, new_mem, rxq_idx);
 		if (err)
 			goto err_start_queue;
 	} else {
@@ -60,6 +64,7 @@ int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx)
 	return 0;
 
 err_start_queue:
+	__netdev_queue_config(dev, rxq_idx, &qcfg, false);
 	/* Restarting the queue with old_mem should be successful as we haven't
 	 * changed any of the queue configuration, and there is not much we can
 	 * do to recover from a failure here.
@@ -67,7 +72,7 @@ int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx)
 	 * WARN if we fail to recover the old rx queue, and at least free
 	 * old_mem so we don't also leak that.
 	 */
-	if (qops->ndo_queue_start(dev, old_mem, rxq_idx)) {
+	if (qops->ndo_queue_start(dev, &qcfg, old_mem, rxq_idx)) {
 		WARN(1,
 		     "Failed to restart old queue in error path. RX queue %d may be unhealthy.",
 		     rxq_idx);
-- 
2.49.0

[RFC v2 13/24] net: pass extack to netdev_rx_queue_restart()

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

Pass extack to netdev_rx_queue_restart(). Subsequent change will need it.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 2 +-
 drivers/net/netdevsim/netdev.c            | 2 +-
 include/net/netdev_rx_queue.h             | 3 ++-
 net/core/netdev_rx_queue.c                | 7 ++++---
 4 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 96b6fa696247..e8e88782fdf1 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -11532,7 +11532,7 @@ static void bnxt_irq_affinity_notify(struct irq_affinity_notify *notify,
 
 	netdev_lock(irq->bp->dev);
 	if (netif_running(irq->bp->dev)) {
-		err = netdev_rx_queue_restart(irq->bp->dev, irq->ring_nr);
+		err = netdev_rx_queue_restart(irq->bp->dev, irq->ring_nr, NULL);
 		if (err)
 			netdev_err(irq->bp->dev,
 				   "RX queue restart failed: err=%d\n", err);
diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c
index 46cdf31f0354..74b2fe1b1cd3 100644
--- a/drivers/net/netdevsim/netdev.c
+++ b/drivers/net/netdevsim/netdev.c
@@ -865,7 +865,7 @@ nsim_qreset_write(struct file *file, const char __user *data,
 	}
 
 	ns->rq_reset_mode = mode;
-	ret = netdev_rx_queue_restart(ns->netdev, queue);
+	ret = netdev_rx_queue_restart(ns->netdev, queue, NULL);
 	ns->rq_reset_mode = 0;
 	if (ret)
 		goto exit_unlock;
diff --git a/include/net/netdev_rx_queue.h b/include/net/netdev_rx_queue.h
index 8cdcd138b33f..a7def1f94823 100644
--- a/include/net/netdev_rx_queue.h
+++ b/include/net/netdev_rx_queue.h
@@ -56,6 +56,7 @@ get_netdev_rx_queue_index(struct netdev_rx_queue *queue)
 	return index;
 }
 
-int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq);
+int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq,
+			    struct netlink_ext_ack *extack);
 
 #endif
diff --git a/net/core/netdev_rx_queue.c b/net/core/netdev_rx_queue.c
index fb87ce219a8a..420b956a40e4 100644
--- a/net/core/netdev_rx_queue.c
+++ b/net/core/netdev_rx_queue.c
@@ -10,7 +10,8 @@
 #include "dev.h"
 #include "page_pool_priv.h"
 
-int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx)
+int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx,
+			    struct netlink_ext_ack *extack)
 {
 	struct netdev_rx_queue *rxq = __netif_get_rx_queue(dev, rxq_idx);
 	const struct netdev_queue_mgmt_ops *qops = dev->queue_mgmt_ops;
@@ -134,7 +135,7 @@ int __net_mp_open_rxq(struct net_device *dev, unsigned int rxq_idx,
 #endif
 
 	rxq->mp_params = *p;
-	ret = netdev_rx_queue_restart(dev, rxq_idx);
+	ret = netdev_rx_queue_restart(dev, rxq_idx, extack);
 	if (ret) {
 		rxq->mp_params.mp_ops = NULL;
 		rxq->mp_params.mp_priv = NULL;
@@ -177,7 +178,7 @@ void __net_mp_close_rxq(struct net_device *dev, unsigned int ifq_idx,
 
 	rxq->mp_params.mp_ops = NULL;
 	rxq->mp_params.mp_priv = NULL;
-	err = netdev_rx_queue_restart(dev, ifq_idx);
+	err = netdev_rx_queue_restart(dev, ifq_idx, NULL);
 	WARN_ON(err && err != -ENETDOWN);
 }
 
-- 
2.49.0

[RFC v2 14/24] net: add queue config validation callback

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

I imagine (tm) that as the number of per-queue configuration
options grows some of them may conflict for certain drivers.
While the drivers can obviously do all the validation locally
doing so is fairly inconvenient as the config is fed to drivers
piecemeal via different ops (for different params and NIC-wide
vs per-queue).

Add a centralized callback for validating the queue config
in queue ops. The callback gets invoked before each queue restart
and when ring params are modified.

For NIC-wide changes the callback gets invoked for each active
(or active to-be) queue, and additionally with a negative queue
index for NIC-wide defaults. The NIC-wide check is needed in
case all queues have an override active when NIC-wide setting
is changed to an unsupported one. Alternatively we could check
the settings when new queues are enabled (in the channel API),
but accepting invalid config is a bad idea. Users may expect
that resetting a queue override will always work.

The "trick" of passing a negative index is a bit ugly, we may
want to revisit if it causes confusion and bugs. Existing drivers
don't care about the index so it "just works".

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 include/net/netdev_queues.h | 12 ++++++++++++
 net/core/dev.h              |  2 ++
 net/core/netdev_config.c    | 20 ++++++++++++++++++++
 net/core/netdev_rx_queue.c  |  6 ++++++
 net/ethtool/rings.c         |  5 +++++
 5 files changed, 45 insertions(+)

diff --git a/include/net/netdev_queues.h b/include/net/netdev_queues.h
index b850cff71d12..d0cc475ec51e 100644
--- a/include/net/netdev_queues.h
+++ b/include/net/netdev_queues.h
@@ -147,6 +147,14 @@ void netdev_stat_queue_sum(struct net_device *netdev,
  *			defaults. Queue config structs are passed to this
  *			helper before the user-requested settings are applied.
  *
+ * @ndo_queue_cfg_validate: (Optional) Check if queue config is supported.
+ *			Called when configuration affecting a queue may be
+ *			changing, either due to NIC-wide config, or config
+ *			scoped to the queue at a specified index.
+ *			When NIC-wide config is changed the callback will
+ *			be invoked for all queues, and in addition to that
+ *			with a negative queue index for the base settings.
+ *
  * @ndo_queue_mem_alloc: Allocate memory for an RX queue at the specified index.
  *			 The new memory is written at the specified address.
  *
@@ -167,6 +175,10 @@ struct netdev_queue_mgmt_ops {
 	void	(*ndo_queue_cfg_defaults)(struct net_device *dev,
 					  int idx,
 					  struct netdev_queue_config *qcfg);
+	int	(*ndo_queue_cfg_validate)(struct net_device *dev,
+					  int idx,
+					  struct netdev_queue_config *qcfg,
+					  struct netlink_ext_ack *extack);
 	int	(*ndo_queue_mem_alloc)(struct net_device *dev,
 				       struct netdev_queue_config *qcfg,
 				       void *per_queue_mem,
diff --git a/net/core/dev.h b/net/core/dev.h
index 5fdcf97149f9..f51b66403466 100644
--- a/net/core/dev.h
+++ b/net/core/dev.h
@@ -99,6 +99,8 @@ void netdev_free_config(struct net_device *dev);
 int netdev_reconfig_start(struct net_device *dev);
 void __netdev_queue_config(struct net_device *dev, int rxq,
 			   struct netdev_queue_config *qcfg, bool pending);
+int netdev_queue_config_revalidate(struct net_device *dev,
+				   struct netlink_ext_ack *extack);
 
 /* netdev management, shared between various uAPI entry points */
 struct netdev_name_node {
diff --git a/net/core/netdev_config.c b/net/core/netdev_config.c
index bad2d53522f0..fc700b77e4eb 100644
--- a/net/core/netdev_config.c
+++ b/net/core/netdev_config.c
@@ -99,3 +99,23 @@ void netdev_queue_config(struct net_device *dev, int rxq,
 	__netdev_queue_config(dev, rxq, qcfg, true);
 }
 EXPORT_SYMBOL(netdev_queue_config);
+
+int netdev_queue_config_revalidate(struct net_device *dev,
+				   struct netlink_ext_ack *extack)
+{
+	const struct netdev_queue_mgmt_ops *qops = dev->queue_mgmt_ops;
+	struct netdev_queue_config qcfg;
+	int i, err;
+
+	if (!qops || !qops->ndo_queue_cfg_validate)
+		return 0;
+
+	for (i = -1; i < (int)dev->real_num_rx_queues; i++) {
+		netdev_queue_config(dev, i, &qcfg);
+		err = qops->ndo_queue_cfg_validate(dev, i, &qcfg, extack);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
diff --git a/net/core/netdev_rx_queue.c b/net/core/netdev_rx_queue.c
index 420b956a40e4..39834b196e95 100644
--- a/net/core/netdev_rx_queue.c
+++ b/net/core/netdev_rx_queue.c
@@ -37,6 +37,12 @@ int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx,
 
 	netdev_queue_config(dev, rxq_idx, &qcfg);
 
+	if (qops->ndo_queue_cfg_validate) {
+		err = qops->ndo_queue_cfg_validate(dev, rxq_idx, &qcfg, extack);
+		if (err)
+			goto err_free_old_mem;
+	}
+
 	err = qops->ndo_queue_mem_alloc(dev, &qcfg, new_mem, rxq_idx);
 	if (err)
 		goto err_free_old_mem;
diff --git a/net/ethtool/rings.c b/net/ethtool/rings.c
index 6a74e7e4064e..7884d10c090f 100644
--- a/net/ethtool/rings.c
+++ b/net/ethtool/rings.c
@@ -4,6 +4,7 @@
 
 #include "netlink.h"
 #include "common.h"
+#include "../core/dev.h"
 
 struct rings_req_info {
 	struct ethnl_req_info		base;
@@ -307,6 +308,10 @@ ethnl_set_rings(struct ethnl_req_info *req_info, struct genl_info *info)
 	dev->cfg_pending->hds_config = kernel_ringparam.tcp_data_split;
 	dev->cfg_pending->hds_thresh = kernel_ringparam.hds_thresh;
 
+	ret = netdev_queue_config_revalidate(dev, info->extack);
+	if (ret)
+		return ret;
+
 	ret = dev->ethtool_ops->set_ringparam(dev, &ringparam,
 					      &kernel_ringparam, info->extack);
 	return ret < 0 ? ret : 1;
-- 
2.49.0

[RFC v2 15/24] eth: bnxt: always set the queue mgmt ops

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

Core provides a centralized callback for validating per-queue settings
but the callback is part of the queue management ops. Having the ops
conditionally set complicates the parts of the driver which could
otherwise lean on the core to feed it the correct settings.

Always set the queue ops, but provide no restart-related callbacks if
queue ops are not supported by the device. This should maintain current
behavior, the check in netdev_rx_queue_restart() looks both at op struct
and individual ops.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[pavel: reflow mgmt ops assignment]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index e8e88782fdf1..933815026899 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -16118,6 +16118,9 @@ static const struct netdev_queue_mgmt_ops bnxt_queue_mgmt_ops = {
 	.ndo_queue_stop		= bnxt_queue_stop,
 };
 
+static const struct netdev_queue_mgmt_ops bnxt_queue_mgmt_ops_unsupp = {
+};
+
 static void bnxt_remove_one(struct pci_dev *pdev)
 {
 	struct net_device *dev = pci_get_drvdata(pdev);
@@ -16771,6 +16774,8 @@ static int bnxt_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	if (BNXT_SUPPORTS_NTUPLE_VNIC(bp))
 		bp->rss_cap |= BNXT_RSS_CAP_MULTI_RSS_CTX;
+
+	dev->queue_mgmt_ops = &bnxt_queue_mgmt_ops_unsupp;
 	if (BNXT_SUPPORTS_QUEUE_API(bp))
 		dev->queue_mgmt_ops = &bnxt_queue_mgmt_ops;
 	dev->request_ops_lock = true;
-- 
2.49.0

[RFC v2 16/24] eth: bnxt: store the rx buf size per queue

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

In normal operation only a subset of queues is configured for
zero-copy. Since zero-copy is the main use for larger buffer
sizes we need to configure the sizes per queue.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c     | 46 ++++++++++---------
 drivers/net/ethernet/broadcom/bnxt/bnxt.h     |  1 +
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c |  6 +--
 drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h |  2 +-
 4 files changed, 30 insertions(+), 25 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 933815026899..40cfc48cd439 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -900,7 +900,7 @@ static void bnxt_tx_int(struct bnxt *bp, struct bnxt_napi *bnapi, int budget)
 
 static bool bnxt_separate_head_pool(struct bnxt_rx_ring_info *rxr)
 {
-	return rxr->need_head_pool || PAGE_SIZE > rxr->bnapi->bp->rx_page_size;
+	return rxr->need_head_pool || PAGE_SIZE > rxr->rx_page_size;
 }
 
 static struct page *__bnxt_alloc_rx_page(struct bnxt *bp, dma_addr_t *mapping,
@@ -910,9 +910,9 @@ static struct page *__bnxt_alloc_rx_page(struct bnxt *bp, dma_addr_t *mapping,
 {
 	struct page *page;
 
-	if (PAGE_SIZE > bp->rx_page_size) {
+	if (PAGE_SIZE > rxr->rx_page_size) {
 		page = page_pool_dev_alloc_frag(rxr->page_pool, offset,
-						bp->rx_page_size);
+						rxr->rx_page_size);
 	} else {
 		page = page_pool_dev_alloc_pages(rxr->page_pool);
 		*offset = 0;
@@ -1144,9 +1144,9 @@ static struct sk_buff *bnxt_rx_multi_page_skb(struct bnxt *bp,
 		return NULL;
 	}
 	dma_addr -= bp->rx_dma_offset;
-	dma_sync_single_for_cpu(&bp->pdev->dev, dma_addr, bp->rx_page_size,
+	dma_sync_single_for_cpu(&bp->pdev->dev, dma_addr, rxr->rx_page_size,
 				bp->rx_dir);
-	skb = napi_build_skb(data_ptr - bp->rx_offset, bp->rx_page_size);
+	skb = napi_build_skb(data_ptr - bp->rx_offset, rxr->rx_page_size);
 	if (!skb) {
 		page_pool_recycle_direct(rxr->page_pool, page);
 		return NULL;
@@ -1178,7 +1178,7 @@ static struct sk_buff *bnxt_rx_page_skb(struct bnxt *bp,
 		return NULL;
 	}
 	dma_addr -= bp->rx_dma_offset;
-	dma_sync_single_for_cpu(&bp->pdev->dev, dma_addr, bp->rx_page_size,
+	dma_sync_single_for_cpu(&bp->pdev->dev, dma_addr, rxr->rx_page_size,
 				bp->rx_dir);
 
 	if (unlikely(!payload))
@@ -1192,7 +1192,7 @@ static struct sk_buff *bnxt_rx_page_skb(struct bnxt *bp,
 
 	skb_mark_for_recycle(skb);
 	off = (void *)data_ptr - page_address(page);
-	skb_add_rx_frag(skb, 0, page, off, len, bp->rx_page_size);
+	skb_add_rx_frag(skb, 0, page, off, len, rxr->rx_page_size);
 	memcpy(skb->data - NET_IP_ALIGN, data_ptr - NET_IP_ALIGN,
 	       payload + NET_IP_ALIGN);
 
@@ -1277,7 +1277,7 @@ static u32 __bnxt_rx_agg_netmems(struct bnxt *bp,
 		if (skb) {
 			skb_add_rx_frag_netmem(skb, i, cons_rx_buf->netmem,
 					       cons_rx_buf->offset,
-					       frag_len, bp->rx_page_size);
+					       frag_len, rxr->rx_page_size);
 		} else {
 			skb_frag_t *frag = &shinfo->frags[i];
 
@@ -1302,7 +1302,7 @@ static u32 __bnxt_rx_agg_netmems(struct bnxt *bp,
 			if (skb) {
 				skb->len -= frag_len;
 				skb->data_len -= frag_len;
-				skb->truesize -= bp->rx_page_size;
+				skb->truesize -= rxr->rx_page_size;
 			}
 
 			--shinfo->nr_frags;
@@ -1317,7 +1317,7 @@ static u32 __bnxt_rx_agg_netmems(struct bnxt *bp,
 		}
 
 		page_pool_dma_sync_netmem_for_cpu(rxr->page_pool, netmem, 0,
-						  bp->rx_page_size);
+						  rxr->rx_page_size);
 
 		total_frag_len += frag_len;
 		prod = NEXT_RX_AGG(prod);
@@ -2270,8 +2270,7 @@ static int bnxt_rx_pkt(struct bnxt *bp, struct bnxt_cp_ring_info *cpr,
 			if (!skb)
 				goto oom_next_rx;
 		} else {
-			skb = bnxt_xdp_build_skb(bp, skb, agg_bufs,
-						 rxr->page_pool, &xdp);
+			skb = bnxt_xdp_build_skb(bp, skb, agg_bufs, rxr, &xdp);
 			if (!skb) {
 				/* we should be able to free the old skb here */
 				bnxt_xdp_buff_frags_free(rxr, &xdp);
@@ -3819,7 +3818,7 @@ static int bnxt_alloc_rx_page_pool(struct bnxt *bp,
 	if (BNXT_RX_PAGE_MODE(bp))
 		pp.pool_size += bp->rx_ring_size / rx_size_fac;
 
-	pp.order = get_order(bp->rx_page_size);
+	pp.order = get_order(rxr->rx_page_size);
 	pp.nid = numa_node;
 	pp.napi = &rxr->bnapi->napi;
 	pp.netdev = bp->dev;
@@ -4306,6 +4305,8 @@ static void bnxt_init_ring_struct(struct bnxt *bp)
 		if (!rxr)
 			goto skip_rx;
 
+		rxr->rx_page_size = bp->rx_page_size;
+
 		ring = &rxr->rx_ring_struct;
 		rmem = &ring->ring_mem;
 		rmem->nr_pages = bp->rx_nr_pages;
@@ -4465,7 +4466,7 @@ static void bnxt_init_one_rx_agg_ring_rxbd(struct bnxt *bp,
 	ring = &rxr->rx_agg_ring_struct;
 	ring->fw_ring_id = INVALID_HW_RING_ID;
 	if ((bp->flags & BNXT_FLAG_AGG_RINGS)) {
-		type = ((u32)bp->rx_page_size << RX_BD_LEN_SHIFT) |
+		type = ((u32)rxr->rx_page_size << RX_BD_LEN_SHIFT) |
 			RX_BD_TYPE_RX_AGG_BD | RX_BD_FLAGS_SOP;
 
 		bnxt_init_rxbd_pages(ring, type);
@@ -7030,6 +7031,7 @@ static void bnxt_hwrm_ring_grp_free(struct bnxt *bp)
 
 static void bnxt_set_rx_ring_params_p5(struct bnxt *bp, u32 ring_type,
 				       struct hwrm_ring_alloc_input *req,
+				       struct bnxt_rx_ring_info *rxr,
 				       struct bnxt_ring_struct *ring)
 {
 	struct bnxt_ring_grp_info *grp_info = &bp->grp_info[ring->grp_idx];
@@ -7039,7 +7041,7 @@ static void bnxt_set_rx_ring_params_p5(struct bnxt *bp, u32 ring_type,
 	if (ring_type == HWRM_RING_ALLOC_AGG) {
 		req->ring_type = RING_ALLOC_REQ_RING_TYPE_RX_AGG;
 		req->rx_ring_id = cpu_to_le16(grp_info->rx_fw_ring_id);
-		req->rx_buf_size = cpu_to_le16(bp->rx_page_size);
+		req->rx_buf_size = cpu_to_le16(rxr->rx_page_size);
 		enables |= RING_ALLOC_REQ_ENABLES_RX_RING_ID_VALID;
 	} else {
 		req->rx_buf_size = cpu_to_le16(bp->rx_buf_use_size);
@@ -7053,6 +7055,7 @@ static void bnxt_set_rx_ring_params_p5(struct bnxt *bp, u32 ring_type,
 }
 
 static int hwrm_ring_alloc_send_msg(struct bnxt *bp,
+				    struct bnxt_rx_ring_info *rxr,
 				    struct bnxt_ring_struct *ring,
 				    u32 ring_type, u32 map_index)
 {
@@ -7109,7 +7112,8 @@ static int hwrm_ring_alloc_send_msg(struct bnxt *bp,
 			      cpu_to_le32(bp->rx_ring_mask + 1) :
 			      cpu_to_le32(bp->rx_agg_ring_mask + 1);
 		if (bp->flags & BNXT_FLAG_CHIP_P5_PLUS)
-			bnxt_set_rx_ring_params_p5(bp, ring_type, req, ring);
+			bnxt_set_rx_ring_params_p5(bp, ring_type, req,
+						   rxr, ring);
 		break;
 	case HWRM_RING_ALLOC_CMPL:
 		req->ring_type = RING_ALLOC_REQ_RING_TYPE_L2_CMPL;
@@ -7257,7 +7261,7 @@ static int bnxt_hwrm_rx_ring_alloc(struct bnxt *bp,
 	u32 map_idx = bnapi->index;
 	int rc;
 
-	rc = hwrm_ring_alloc_send_msg(bp, ring, type, map_idx);
+	rc = hwrm_ring_alloc_send_msg(bp, rxr, ring, type, map_idx);
 	if (rc)
 		return rc;
 
@@ -7277,7 +7281,7 @@ static int bnxt_hwrm_rx_agg_ring_alloc(struct bnxt *bp,
 	int rc;
 
 	map_idx = grp_idx + bp->rx_nr_rings;
-	rc = hwrm_ring_alloc_send_msg(bp, ring, type, map_idx);
+	rc = hwrm_ring_alloc_send_msg(bp, rxr, ring, type, map_idx);
 	if (rc)
 		return rc;
 
@@ -7301,7 +7305,7 @@ static int bnxt_hwrm_cp_ring_alloc_p5(struct bnxt *bp,
 
 	ring = &cpr->cp_ring_struct;
 	ring->handle = BNXT_SET_NQ_HDL(cpr);
-	rc = hwrm_ring_alloc_send_msg(bp, ring, type, map_idx);
+	rc = hwrm_ring_alloc_send_msg(bp, NULL, ring, type, map_idx);
 	if (rc)
 		return rc;
 	bnxt_set_db(bp, &cpr->cp_db, type, map_idx, ring->fw_ring_id);
@@ -7316,7 +7320,7 @@ static int bnxt_hwrm_tx_ring_alloc(struct bnxt *bp,
 	const u32 type = HWRM_RING_ALLOC_TX;
 	int rc;
 
-	rc = hwrm_ring_alloc_send_msg(bp, ring, type, tx_idx);
+	rc = hwrm_ring_alloc_send_msg(bp, NULL, ring, type, tx_idx);
 	if (rc)
 		return rc;
 	bnxt_set_db(bp, &txr->tx_db, type, tx_idx, ring->fw_ring_id);
@@ -7342,7 +7346,7 @@ static int bnxt_hwrm_ring_alloc(struct bnxt *bp)
 
 		vector = bp->irq_tbl[map_idx].vector;
 		disable_irq_nosync(vector);
-		rc = hwrm_ring_alloc_send_msg(bp, ring, type, map_idx);
+		rc = hwrm_ring_alloc_send_msg(bp, NULL, ring, type, map_idx);
 		if (rc) {
 			enable_irq(vector);
 			goto err_out;
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
index 56aafae568f8..4f9d4c71c0e2 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -1107,6 +1107,7 @@ struct bnxt_rx_ring_info {
 
 	unsigned long		*rx_agg_bmap;
 	u16			rx_agg_bmap_size;
+	u16			rx_page_size;
 	bool                    need_head_pool;
 
 	dma_addr_t		rx_desc_mapping[MAX_RX_PAGES];
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
index 41d3ba56ba41..19dda0201c69 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
@@ -183,7 +183,7 @@ void bnxt_xdp_buff_init(struct bnxt *bp, struct bnxt_rx_ring_info *rxr,
 			u16 cons, u8 *data_ptr, unsigned int len,
 			struct xdp_buff *xdp)
 {
-	u32 buflen = bp->rx_page_size;
+	u32 buflen = rxr->rx_page_size;
 	struct bnxt_sw_rx_bd *rx_buf;
 	struct pci_dev *pdev;
 	dma_addr_t mapping;
@@ -461,7 +461,7 @@ int bnxt_xdp(struct net_device *dev, struct netdev_bpf *xdp)
 
 struct sk_buff *
 bnxt_xdp_build_skb(struct bnxt *bp, struct sk_buff *skb, u8 num_frags,
-		   struct page_pool *pool, struct xdp_buff *xdp)
+		   struct bnxt_rx_ring_info *rxr, struct xdp_buff *xdp)
 {
 	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
 
@@ -470,7 +470,7 @@ bnxt_xdp_build_skb(struct bnxt *bp, struct sk_buff *skb, u8 num_frags,
 
 	xdp_update_skb_shared_info(skb, num_frags,
 				   sinfo->xdp_frags_size,
-				   bp->rx_page_size * num_frags,
+				   rxr->rx_page_size * num_frags,
 				   xdp_buff_is_frag_pfmemalloc(xdp));
 	return skb;
 }
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h
index 220285e190fc..8933a0dec09a 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h
@@ -32,6 +32,6 @@ void bnxt_xdp_buff_init(struct bnxt *bp, struct bnxt_rx_ring_info *rxr,
 void bnxt_xdp_buff_frags_free(struct bnxt_rx_ring_info *rxr,
 			      struct xdp_buff *xdp);
 struct sk_buff *bnxt_xdp_build_skb(struct bnxt *bp, struct sk_buff *skb,
-				   u8 num_frags, struct page_pool *pool,
+				   u8 num_frags, struct bnxt_rx_ring_info *rxr,
 				   struct xdp_buff *xdp);
 #endif
-- 
2.49.0

[RFC v2 17/24] eth: bnxt: adjust the fill level of agg queues with larger buffers

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

The driver tries to provision more agg buffers than header buffers
since multiple agg segments can reuse the same header. The calculation
/ heuristic tries to provide enough pages for 65k of data for each header
(or 4 frags per header if the result is too big). This calculation is
currently global to the adapter. If we increase the buffer sizes 8x
we don't want 8x the amount of memory sitting on the rings.
Luckily we don't have to fill the rings completely, adjust
the fill level dynamically in case particular queue has buffers
larger than the global size.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[pavel: rebase on top of agg_size_fac, assert agg_size_fac]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 27 +++++++++++++++++++----
 1 file changed, 23 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 40cfc48cd439..a00c2a829b6b 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -3805,16 +3805,33 @@ static void bnxt_free_rx_rings(struct bnxt *bp)
 	}
 }
 
+static int bnxt_rx_agg_ring_fill_level(struct bnxt *bp,
+				       struct bnxt_rx_ring_info *rxr)
+{
+	/* User may have chosen larger than default rx_page_size,
+	 * we keep the ring sizes uniform and also want uniform amount
+	 * of bytes consumed per ring, so cap how much of the rings we fill.
+	 */
+	int fill_level = bp->rx_agg_ring_size;
+
+	if (rxr->rx_page_size > bp->rx_page_size)
+		fill_level /= rxr->rx_page_size / bp->rx_page_size;
+
+	return fill_level;
+}
+
 static int bnxt_alloc_rx_page_pool(struct bnxt *bp,
 				   struct bnxt_rx_ring_info *rxr,
 				   int numa_node)
 {
-	const unsigned int agg_size_fac = PAGE_SIZE / BNXT_RX_PAGE_SIZE;
+	const unsigned int agg_size_fac = rxr->rx_page_size / BNXT_RX_PAGE_SIZE;
 	const unsigned int rx_size_fac = PAGE_SIZE / SZ_4K;
 	struct page_pool_params pp = { 0 };
 	struct page_pool *pool;
 
-	pp.pool_size = bp->rx_agg_ring_size / agg_size_fac;
+	WARN_ON_ONCE(agg_size_fac == 0);
+
+	pp.pool_size = bnxt_rx_agg_ring_fill_level(bp, rxr) / agg_size_fac;
 	if (BNXT_RX_PAGE_MODE(bp))
 		pp.pool_size += bp->rx_ring_size / rx_size_fac;
 
@@ -4384,11 +4401,13 @@ static void bnxt_alloc_one_rx_ring_netmem(struct bnxt *bp,
 					  struct bnxt_rx_ring_info *rxr,
 					  int ring_nr)
 {
+	int fill_level, i;
 	u32 prod;
-	int i;
+
+	fill_level = bnxt_rx_agg_ring_fill_level(bp, rxr);
 
 	prod = rxr->rx_agg_prod;
-	for (i = 0; i < bp->rx_agg_ring_size; i++) {
+	for (i = 0; i < fill_level; i++) {
 		if (bnxt_alloc_rx_netmem(bp, rxr, prod, GFP_KERNEL)) {
 			netdev_warn(bp->dev, "init'ed rx ring %d with %d/%d pages only\n",
 				    ring_nr, i, bp->rx_ring_size);
-- 
2.49.0

Re: [RFC v2 17/24] eth: bnxt: adjust the fill level of agg queues with larger buffers

[Stanislav Fomichev]

On 08/08, Pavel Begunkov wrote:
> From: Jakub Kicinski <kuba@kernel.org>
> 
> The driver tries to provision more agg buffers than header buffers
> since multiple agg segments can reuse the same header. The calculation
> / heuristic tries to provide enough pages for 65k of data for each header
> (or 4 frags per header if the result is too big). This calculation is
> currently global to the adapter. If we increase the buffer sizes 8x
> we don't want 8x the amount of memory sitting on the rings.
> Luckily we don't have to fill the rings completely, adjust
> the fill level dynamically in case particular queue has buffers
> larger than the global size.
> 
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> [pavel: rebase on top of agg_size_fac, assert agg_size_fac]
> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
> ---
>  drivers/net/ethernet/broadcom/bnxt/bnxt.c | 27 +++++++++++++++++++----
>  1 file changed, 23 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> index 40cfc48cd439..a00c2a829b6b 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> @@ -3805,16 +3805,33 @@ static void bnxt_free_rx_rings(struct bnxt *bp)
>  	}
>  }
>  
> +static int bnxt_rx_agg_ring_fill_level(struct bnxt *bp,
> +				       struct bnxt_rx_ring_info *rxr)
> +{
> +	/* User may have chosen larger than default rx_page_size,
> +	 * we keep the ring sizes uniform and also want uniform amount
> +	 * of bytes consumed per ring, so cap how much of the rings we fill.
> +	 */
> +	int fill_level = bp->rx_agg_ring_size;
> +
> +	if (rxr->rx_page_size > bp->rx_page_size)
> +		fill_level /= rxr->rx_page_size / bp->rx_page_size;
> +
> +	return fill_level;
> +}
> +
>  static int bnxt_alloc_rx_page_pool(struct bnxt *bp,
>  				   struct bnxt_rx_ring_info *rxr,
>  				   int numa_node)
>  {
> -	const unsigned int agg_size_fac = PAGE_SIZE / BNXT_RX_PAGE_SIZE;
> +	const unsigned int agg_size_fac = rxr->rx_page_size / BNXT_RX_PAGE_SIZE;
>  	const unsigned int rx_size_fac = PAGE_SIZE / SZ_4K;
>  	struct page_pool_params pp = { 0 };
>  	struct page_pool *pool;
>  
> -	pp.pool_size = bp->rx_agg_ring_size / agg_size_fac;

[..]

> +	WARN_ON_ONCE(agg_size_fac == 0);

nit: do we need to make this if (WARN_ON_ONCE(...)) agg_size_fac = 1?
Otherwise you're gonna divide by zero on the next line. Or properly
return some EINVAL instead?

> +
> +	pp.pool_size = bnxt_rx_agg_ring_fill_level(bp, rxr) / agg_size_fac;

Re: [RFC v2 17/24] eth: bnxt: adjust the fill level of agg queues with larger buffers

[Pavel Begunkov]

On 8/8/25 19:03, Stanislav Fomichev wrote:
> On 08/08, Pavel Begunkov wrote:
...>>   static int bnxt_alloc_rx_page_pool(struct bnxt *bp,
>>   				   struct bnxt_rx_ring_info *rxr,
>>   				   int numa_node)
>>   {
>> -	const unsigned int agg_size_fac = PAGE_SIZE / BNXT_RX_PAGE_SIZE;
>> +	const unsigned int agg_size_fac = rxr->rx_page_size / BNXT_RX_PAGE_SIZE;
>>   	const unsigned int rx_size_fac = PAGE_SIZE / SZ_4K;
>>   	struct page_pool_params pp = { 0 };
>>   	struct page_pool *pool;
>>   
>> -	pp.pool_size = bp->rx_agg_ring_size / agg_size_fac;
> 
> [..]
> 
>> +	WARN_ON_ONCE(agg_size_fac == 0);
> 
> nit: do we need to make this if (WARN_ON_ONCE(...)) agg_size_fac = 1?
> Otherwise you're gonna divide by zero on the next line. Or properly
> return some EINVAL instead?
I can add it to be safe, but fwiw it shouldn't happen either way

> 
>> +
>> +	pp.pool_size = bnxt_rx_agg_ring_fill_level(bp, rxr) / agg_size_fac;

-- 
Pavel Begunkov

[RFC v2 18/24] netdev: add support for setting rx-buf-len per queue

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

Zero-copy APIs increase the cost of buffer management. They also extend
this cost to user space applications which may be used to dealing with
much larger buffers. Allow setting rx-buf-len per queue, devices with
HW-GRO support can commonly fill buffers up to 32k (or rather 64k - 1
but that's not a power of 2..)

The implementation adds a new option to the netdev netlink, rather
than ethtool. The NIC-wide setting lives in ethtool ringparams so
one could argue that we should be extending the ethtool API.
OTOH netdev API is where we already have queue-get, and it's how
zero-copy applications bind memory providers.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 Documentation/netlink/specs/netdev.yaml | 15 ++++
 include/net/netdev_queues.h             |  5 ++
 include/net/netlink.h                   | 19 +++++
 include/uapi/linux/netdev.h             |  2 +
 net/core/netdev-genl-gen.c              | 15 ++++
 net/core/netdev-genl-gen.h              |  1 +
 net/core/netdev-genl.c                  | 92 +++++++++++++++++++++++++
 net/core/netdev_config.c                | 16 +++++
 tools/include/uapi/linux/netdev.h       |  2 +
 9 files changed, 167 insertions(+)

diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml
index c035dc0f64fd..498c4bcafdbd 100644
--- a/Documentation/netlink/specs/netdev.yaml
+++ b/Documentation/netlink/specs/netdev.yaml
@@ -338,6 +338,10 @@ attribute-sets:
         doc: XSK information for this queue, if any.
         type: nest
         nested-attributes: xsk-info
+      -
+        name: rx-buf-len
+        doc: Per-queue configuration of ETHTOOL_A_RINGS_RX_BUF_LEN.
+        type: u32
   -
     name: qstats
     doc: |
@@ -771,6 +775,17 @@ operations:
         reply:
           attributes:
             - id
+    -
+      name: queue-set
+      doc: Set per-queue configurable options.
+      attribute-set: queue
+      do:
+        request:
+          attributes:
+            - ifindex
+            - type
+            - id
+            - rx-buf-len
 
 kernel-family:
   headers: ["net/netdev_netlink.h"]
diff --git a/include/net/netdev_queues.h b/include/net/netdev_queues.h
index d0cc475ec51e..b69b1d519dcb 100644
--- a/include/net/netdev_queues.h
+++ b/include/net/netdev_queues.h
@@ -39,6 +39,7 @@ struct netdev_config {
 
 /* Same semantics as fields in struct netdev_config */
 struct netdev_queue_config {
+	u32	rx_buf_len;
 };
 
 /* See the netdev.yaml spec for definition of each statistic */
@@ -141,6 +142,8 @@ void netdev_stat_queue_sum(struct net_device *netdev,
 /**
  * struct netdev_queue_mgmt_ops - netdev ops for queue management
  *
+ * @supported_ring_params: ring params supported per queue (ETHTOOL_RING_USE_*).
+ *
  * @ndo_queue_mem_size: Size of the struct that describes a queue's memory.
  *
  * @ndo_queue_cfg_defaults: (Optional) Populate queue config struct with
@@ -171,6 +174,8 @@ void netdev_stat_queue_sum(struct net_device *netdev,
  * be called for an interface which is open.
  */
 struct netdev_queue_mgmt_ops {
+	u32     supported_ring_params;
+
 	size_t	ndo_queue_mem_size;
 	void	(*ndo_queue_cfg_defaults)(struct net_device *dev,
 					  int idx,
diff --git a/include/net/netlink.h b/include/net/netlink.h
index 1a8356ca4b78..29989ad81ddd 100644
--- a/include/net/netlink.h
+++ b/include/net/netlink.h
@@ -2200,6 +2200,25 @@ static inline struct nla_bitfield32 nla_get_bitfield32(const struct nlattr *nla)
 	return tmp;
 }
 
+/**
+ * nla_update_u32() - update u32 value from NLA_U32 attribute
+ * @dst:  value to update
+ * @attr: netlink attribute with new value or null
+ *
+ * Copy the u32 value from NLA_U32 netlink attribute @attr into variable
+ * pointed to by @dst; do nothing if @attr is null.
+ *
+ * Return: true if this function changed the value of @dst, otherwise false.
+ */
+static inline bool nla_update_u32(u32 *dst, const struct nlattr *attr)
+{
+	u32 old_val = *dst;
+
+	if (attr)
+		*dst = nla_get_u32(attr);
+	return *dst != old_val;
+}
+
 /**
  * nla_memdup - duplicate attribute memory (kmemdup)
  * @src: netlink attribute to duplicate from
diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h
index 48eb49aa03d4..820f89b67a72 100644
--- a/include/uapi/linux/netdev.h
+++ b/include/uapi/linux/netdev.h
@@ -158,6 +158,7 @@ enum {
 	NETDEV_A_QUEUE_DMABUF,
 	NETDEV_A_QUEUE_IO_URING,
 	NETDEV_A_QUEUE_XSK,
+	NETDEV_A_QUEUE_RX_BUF_LEN,
 
 	__NETDEV_A_QUEUE_MAX,
 	NETDEV_A_QUEUE_MAX = (__NETDEV_A_QUEUE_MAX - 1)
@@ -226,6 +227,7 @@ enum {
 	NETDEV_CMD_BIND_RX,
 	NETDEV_CMD_NAPI_SET,
 	NETDEV_CMD_BIND_TX,
+	NETDEV_CMD_QUEUE_SET,
 
 	__NETDEV_CMD_MAX,
 	NETDEV_CMD_MAX = (__NETDEV_CMD_MAX - 1)
diff --git a/net/core/netdev-genl-gen.c b/net/core/netdev-genl-gen.c
index e9a2a6f26cb7..d053306a3af8 100644
--- a/net/core/netdev-genl-gen.c
+++ b/net/core/netdev-genl-gen.c
@@ -106,6 +106,14 @@ static const struct nla_policy netdev_bind_tx_nl_policy[NETDEV_A_DMABUF_FD + 1]
 	[NETDEV_A_DMABUF_FD] = { .type = NLA_U32, },
 };
 
+/* NETDEV_CMD_QUEUE_SET - do */
+static const struct nla_policy netdev_queue_set_nl_policy[NETDEV_A_QUEUE_RX_BUF_LEN + 1] = {
+	[NETDEV_A_QUEUE_IFINDEX] = NLA_POLICY_MIN(NLA_U32, 1),
+	[NETDEV_A_QUEUE_TYPE] = NLA_POLICY_MAX(NLA_U32, 1),
+	[NETDEV_A_QUEUE_ID] = { .type = NLA_U32, },
+	[NETDEV_A_QUEUE_RX_BUF_LEN] = { .type = NLA_U32, },
+};
+
 /* Ops table for netdev */
 static const struct genl_split_ops netdev_nl_ops[] = {
 	{
@@ -204,6 +212,13 @@ static const struct genl_split_ops netdev_nl_ops[] = {
 		.maxattr	= NETDEV_A_DMABUF_FD,
 		.flags		= GENL_CMD_CAP_DO,
 	},
+	{
+		.cmd		= NETDEV_CMD_QUEUE_SET,
+		.doit		= netdev_nl_queue_set_doit,
+		.policy		= netdev_queue_set_nl_policy,
+		.maxattr	= NETDEV_A_QUEUE_RX_BUF_LEN,
+		.flags		= GENL_CMD_CAP_DO,
+	},
 };
 
 static const struct genl_multicast_group netdev_nl_mcgrps[] = {
diff --git a/net/core/netdev-genl-gen.h b/net/core/netdev-genl-gen.h
index cf3fad74511f..b7f5e5d9fca9 100644
--- a/net/core/netdev-genl-gen.h
+++ b/net/core/netdev-genl-gen.h
@@ -35,6 +35,7 @@ int netdev_nl_qstats_get_dumpit(struct sk_buff *skb,
 int netdev_nl_bind_rx_doit(struct sk_buff *skb, struct genl_info *info);
 int netdev_nl_napi_set_doit(struct sk_buff *skb, struct genl_info *info);
 int netdev_nl_bind_tx_doit(struct sk_buff *skb, struct genl_info *info);
+int netdev_nl_queue_set_doit(struct sk_buff *skb, struct genl_info *info);
 
 enum {
 	NETDEV_NLGRP_MGMT,
diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c
index 6314eb7bdf69..abb128e45fcf 100644
--- a/net/core/netdev-genl.c
+++ b/net/core/netdev-genl.c
@@ -386,6 +386,30 @@ static int nla_put_napi_id(struct sk_buff *skb, const struct napi_struct *napi)
 	return 0;
 }
 
+static int
+netdev_nl_queue_fill_cfg(struct sk_buff *rsp, struct net_device *netdev,
+			 u32 q_idx, u32 q_type)
+{
+	struct netdev_queue_config *qcfg;
+
+	if (!netdev_need_ops_lock(netdev))
+		return 0;
+
+	qcfg = &netdev->cfg->qcfg[q_idx];
+	switch (q_type) {
+	case NETDEV_QUEUE_TYPE_RX:
+		if (qcfg->rx_buf_len &&
+		    nla_put_u32(rsp, NETDEV_A_QUEUE_RX_BUF_LEN,
+				qcfg->rx_buf_len))
+			return -EMSGSIZE;
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
 static int
 netdev_nl_queue_fill_one(struct sk_buff *rsp, struct net_device *netdev,
 			 u32 q_idx, u32 q_type, const struct genl_info *info)
@@ -433,6 +457,9 @@ netdev_nl_queue_fill_one(struct sk_buff *rsp, struct net_device *netdev,
 		break;
 	}
 
+	if (netdev_nl_queue_fill_cfg(rsp, netdev, q_idx, q_type))
+		goto nla_put_failure;
+
 	genlmsg_end(rsp, hdr);
 
 	return 0;
@@ -572,6 +599,71 @@ int netdev_nl_queue_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
 	return err;
 }
 
+int netdev_nl_queue_set_doit(struct sk_buff *skb, struct genl_info *info)
+{
+	struct nlattr * const *tb = info->attrs;
+	struct netdev_queue_config *qcfg;
+	u32 q_id, q_type, ifindex;
+	struct net_device *netdev;
+	bool mod;
+	int ret;
+
+	if (GENL_REQ_ATTR_CHECK(info, NETDEV_A_QUEUE_ID) ||
+	    GENL_REQ_ATTR_CHECK(info, NETDEV_A_QUEUE_TYPE) ||
+	    GENL_REQ_ATTR_CHECK(info, NETDEV_A_QUEUE_IFINDEX))
+		return -EINVAL;
+
+	q_id = nla_get_u32(tb[NETDEV_A_QUEUE_ID]);
+	q_type = nla_get_u32(tb[NETDEV_A_QUEUE_TYPE]);
+	ifindex = nla_get_u32(tb[NETDEV_A_QUEUE_IFINDEX]);
+
+	if (q_type != NETDEV_QUEUE_TYPE_RX) {
+		/* Only Rx params exist right now */
+		NL_SET_BAD_ATTR(info->extack, tb[NETDEV_A_QUEUE_TYPE]);
+		return -EINVAL;
+	}
+
+	ret = 0;
+	netdev = netdev_get_by_index_lock(genl_info_net(info), ifindex);
+	if (!netdev || !netif_device_present(netdev))
+		ret = -ENODEV;
+	else if (!netdev->queue_mgmt_ops)
+		ret = -EOPNOTSUPP;
+	if (ret) {
+		NL_SET_BAD_ATTR(info->extack, tb[NETDEV_A_QUEUE_IFINDEX]);
+		goto exit_unlock;
+	}
+
+	ret = netdev_nl_queue_validate(netdev, q_id, q_type);
+	if (ret) {
+		NL_SET_BAD_ATTR(info->extack, tb[NETDEV_A_QUEUE_ID]);
+		goto exit_unlock;
+	}
+
+	ret = netdev_reconfig_start(netdev);
+	if (ret)
+		goto exit_unlock;
+
+	qcfg = &netdev->cfg_pending->qcfg[q_id];
+	mod = nla_update_u32(&qcfg->rx_buf_len, tb[NETDEV_A_QUEUE_RX_BUF_LEN]);
+	if (!mod)
+		goto exit_free_cfg;
+
+	ret = netdev_rx_queue_restart(netdev, q_id, info->extack);
+	if (ret)
+		goto exit_free_cfg;
+
+	swap(netdev->cfg, netdev->cfg_pending);
+
+exit_free_cfg:
+	__netdev_free_config(netdev->cfg_pending);
+	netdev->cfg_pending = netdev->cfg;
+exit_unlock:
+	if (netdev)
+		netdev_unlock(netdev);
+	return ret;
+}
+
 #define NETDEV_STAT_NOT_SET		(~0ULL)
 
 static void netdev_nl_stats_add(void *_sum, const void *_add, size_t size)
diff --git a/net/core/netdev_config.c b/net/core/netdev_config.c
index fc700b77e4eb..ede02b77470e 100644
--- a/net/core/netdev_config.c
+++ b/net/core/netdev_config.c
@@ -67,11 +67,27 @@ int netdev_reconfig_start(struct net_device *dev)
 void __netdev_queue_config(struct net_device *dev, int rxq,
 			   struct netdev_queue_config *qcfg, bool pending)
 {
+	const struct netdev_config *cfg;
+
+	cfg = pending ? dev->cfg_pending : dev->cfg;
+
 	memset(qcfg, 0, sizeof(*qcfg));
 
 	/* Get defaults from the driver, in case user config not set */
 	if (dev->queue_mgmt_ops->ndo_queue_cfg_defaults)
 		dev->queue_mgmt_ops->ndo_queue_cfg_defaults(dev, rxq, qcfg);
+
+	/* Set config based on device-level settings */
+	if (cfg->rx_buf_len)
+		qcfg->rx_buf_len = cfg->rx_buf_len;
+
+	/* Set config dedicated to this queue */
+	if (rxq >= 0) {
+		const struct netdev_queue_config *user_cfg = &cfg->qcfg[rxq];
+
+		if (user_cfg->rx_buf_len)
+			qcfg->rx_buf_len = user_cfg->rx_buf_len;
+	}
 }
 
 /**
diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h
index 48eb49aa03d4..820f89b67a72 100644
--- a/tools/include/uapi/linux/netdev.h
+++ b/tools/include/uapi/linux/netdev.h
@@ -158,6 +158,7 @@ enum {
 	NETDEV_A_QUEUE_DMABUF,
 	NETDEV_A_QUEUE_IO_URING,
 	NETDEV_A_QUEUE_XSK,
+	NETDEV_A_QUEUE_RX_BUF_LEN,
 
 	__NETDEV_A_QUEUE_MAX,
 	NETDEV_A_QUEUE_MAX = (__NETDEV_A_QUEUE_MAX - 1)
@@ -226,6 +227,7 @@ enum {
 	NETDEV_CMD_BIND_RX,
 	NETDEV_CMD_NAPI_SET,
 	NETDEV_CMD_BIND_TX,
+	NETDEV_CMD_QUEUE_SET,
 
 	__NETDEV_CMD_MAX,
 	NETDEV_CMD_MAX = (__NETDEV_CMD_MAX - 1)
-- 
2.49.0

[RFC v2 19/24] net: wipe the setting of deactived queues

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

Clear out all settings of deactived queues when user changes
the number of channels. We already perform similar cleanup
for shapers.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 net/core/dev.c           |  5 +++++
 net/core/dev.h           |  2 ++
 net/core/netdev_config.c | 13 +++++++++++++
 3 files changed, 20 insertions(+)

diff --git a/net/core/dev.c b/net/core/dev.c
index 8e9af8469421..01264c284c84 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3188,6 +3188,8 @@ int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
 		if (dev->num_tc)
 			netif_setup_tc(dev, txq);
 
+		netdev_queue_config_update_cnt(dev, txq,
+					       dev->real_num_rx_queues);
 		net_shaper_set_real_num_tx_queues(dev, txq);
 
 		dev_qdisc_change_real_num_tx(dev, txq);
@@ -3233,6 +3235,9 @@ int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
 						  rxq);
 		if (rc)
 			return rc;
+
+		netdev_queue_config_update_cnt(dev, dev->real_num_tx_queues,
+					       rxq);
 	}
 
 	dev->real_num_rx_queues = rxq;
diff --git a/net/core/dev.h b/net/core/dev.h
index f51b66403466..a33d8a507bed 100644
--- a/net/core/dev.h
+++ b/net/core/dev.h
@@ -101,6 +101,8 @@ void __netdev_queue_config(struct net_device *dev, int rxq,
 			   struct netdev_queue_config *qcfg, bool pending);
 int netdev_queue_config_revalidate(struct net_device *dev,
 				   struct netlink_ext_ack *extack);
+void netdev_queue_config_update_cnt(struct net_device *dev, unsigned int txq,
+				    unsigned int rxq);
 
 /* netdev management, shared between various uAPI entry points */
 struct netdev_name_node {
diff --git a/net/core/netdev_config.c b/net/core/netdev_config.c
index ede02b77470e..c5ae39e76f40 100644
--- a/net/core/netdev_config.c
+++ b/net/core/netdev_config.c
@@ -64,6 +64,19 @@ int netdev_reconfig_start(struct net_device *dev)
 	return -ENOMEM;
 }
 
+void netdev_queue_config_update_cnt(struct net_device *dev, unsigned int txq,
+				    unsigned int rxq)
+{
+	size_t len;
+
+	if (rxq < dev->real_num_rx_queues) {
+		len = (dev->real_num_rx_queues - rxq) * sizeof(*dev->cfg->qcfg);
+
+		memset(&dev->cfg->qcfg[rxq], 0, len);
+		memset(&dev->cfg_pending->qcfg[rxq], 0, len);
+	}
+}
+
 void __netdev_queue_config(struct net_device *dev, int rxq,
 			   struct netdev_queue_config *qcfg, bool pending)
 {
-- 
2.49.0

[RFC v2 20/24] eth: bnxt: use queue op config validate

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

Move the rx-buf-len config validation to the queue ops.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c     | 40 +++++++++++++++++++
 .../net/ethernet/broadcom/bnxt/bnxt_ethtool.c | 12 ------
 2 files changed, 40 insertions(+), 12 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index a00c2a829b6b..86cbeee2bd3c 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -16133,8 +16133,46 @@ static int bnxt_queue_stop(struct net_device *dev, void *qmem, int idx)
 	return 0;
 }
 
+static int
+bnxt_queue_cfg_validate(struct net_device *dev, int idx,
+			struct netdev_queue_config *qcfg,
+			struct netlink_ext_ack *extack)
+{
+	struct bnxt *bp = netdev_priv(dev);
+
+	/* Older chips need MSS calc so rx_buf_len is not supported,
+	 * but we don't set queue ops for them so we should never get here.
+	 */
+	if (qcfg->rx_buf_len != bp->rx_page_size &&
+	    !(bp->flags & BNXT_FLAG_CHIP_P5_PLUS)) {
+		NL_SET_ERR_MSG_MOD(extack, "changing rx-buf-len not supported");
+		return -EINVAL;
+	}
+
+	if (!is_power_of_2(qcfg->rx_buf_len)) {
+		NL_SET_ERR_MSG_MOD(extack, "rx-buf-len is not power of 2");
+		return -ERANGE;
+	}
+	if (qcfg->rx_buf_len < BNXT_RX_PAGE_SIZE ||
+	    qcfg->rx_buf_len > BNXT_MAX_RX_PAGE_SIZE) {
+		NL_SET_ERR_MSG_MOD(extack, "rx-buf-len out of range");
+		return -ERANGE;
+	}
+	return 0;
+}
+
+static void
+bnxt_queue_cfg_defaults(struct net_device *dev, int idx,
+			struct netdev_queue_config *qcfg)
+{
+	qcfg->rx_buf_len	= BNXT_RX_PAGE_SIZE;
+}
+
 static const struct netdev_queue_mgmt_ops bnxt_queue_mgmt_ops = {
 	.ndo_queue_mem_size	= sizeof(struct bnxt_rx_ring_info),
+
+	.ndo_queue_cfg_defaults	= bnxt_queue_cfg_defaults,
+	.ndo_queue_cfg_validate = bnxt_queue_cfg_validate,
 	.ndo_queue_mem_alloc	= bnxt_queue_mem_alloc,
 	.ndo_queue_mem_free	= bnxt_queue_mem_free,
 	.ndo_queue_start	= bnxt_queue_start,
@@ -16142,6 +16180,8 @@ static const struct netdev_queue_mgmt_ops bnxt_queue_mgmt_ops = {
 };
 
 static const struct netdev_queue_mgmt_ops bnxt_queue_mgmt_ops_unsupp = {
+	.ndo_queue_cfg_defaults	= bnxt_queue_cfg_defaults,
+	.ndo_queue_cfg_validate = bnxt_queue_cfg_validate,
 };
 
 static void bnxt_remove_one(struct pci_dev *pdev)
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
index 2e130eeeabe5..65b8eabdcd24 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -867,18 +867,6 @@ static int bnxt_set_ringparam(struct net_device *dev,
 	if (!kernel_ering->rx_buf_len)	/* Zero means restore default */
 		kernel_ering->rx_buf_len = BNXT_RX_PAGE_SIZE;
 
-	if (kernel_ering->rx_buf_len != bp->rx_page_size &&
-	    !(bp->flags & BNXT_FLAG_CHIP_P5_PLUS)) {
-		NL_SET_ERR_MSG_MOD(extack, "changing rx-buf-len not supported");
-		return -EINVAL;
-	}
-	if (!is_power_of_2(kernel_ering->rx_buf_len) ||
-	    kernel_ering->rx_buf_len < BNXT_RX_PAGE_SIZE ||
-	    kernel_ering->rx_buf_len > BNXT_MAX_RX_PAGE_SIZE) {
-		NL_SET_ERR_MSG_MOD(extack, "rx-buf-len out of range, or not power of 2");
-		return -ERANGE;
-	}
-
 	if (netif_running(dev))
 		bnxt_close_nic(bp, false, false);
 
-- 
2.49.0

[RFC v2 21/24] eth: bnxt: support per queue configuration of rx-buf-len

[Pavel Begunkov]

From: Jakub Kicinski <kuba@kernel.org>

Now that the rx_buf_len is stored and validated per queue allow
it being set differently for different queues. Instead of copying
the device setting for each queue ask the core for the config
via netdev_queue_config().

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
index 86cbeee2bd3c..8f4ae46de936 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -4300,6 +4300,7 @@ static void bnxt_init_ring_struct(struct bnxt *bp)
 
 	for (i = 0; i < bp->cp_nr_rings; i++) {
 		struct bnxt_napi *bnapi = bp->bnapi[i];
+		struct netdev_queue_config qcfg;
 		struct bnxt_ring_mem_info *rmem;
 		struct bnxt_cp_ring_info *cpr;
 		struct bnxt_rx_ring_info *rxr;
@@ -4322,7 +4323,8 @@ static void bnxt_init_ring_struct(struct bnxt *bp)
 		if (!rxr)
 			goto skip_rx;
 
-		rxr->rx_page_size = bp->rx_page_size;
+		netdev_queue_config(bp->dev, i,	&qcfg);
+		rxr->rx_page_size = qcfg.rx_buf_len;
 
 		ring = &rxr->rx_ring_struct;
 		rmem = &ring->ring_mem;
@@ -15857,6 +15859,7 @@ static int bnxt_queue_mem_alloc(struct net_device *dev,
 	clone->rx_agg_prod = 0;
 	clone->rx_sw_agg_prod = 0;
 	clone->rx_next_cons = 0;
+	clone->rx_page_size = qcfg->rx_buf_len;
 	clone->need_head_pool = false;
 
 	rc = bnxt_alloc_rx_page_pool(bp, clone, rxr->page_pool->p.nid);
@@ -15963,6 +15966,8 @@ static void bnxt_copy_rx_ring(struct bnxt *bp,
 	src_ring = &src->rx_ring_struct;
 	src_rmem = &src_ring->ring_mem;
 
+	dst->rx_page_size = src->rx_page_size;
+
 	WARN_ON(dst_rmem->nr_pages != src_rmem->nr_pages);
 	WARN_ON(dst_rmem->page_size != src_rmem->page_size);
 	WARN_ON(dst_rmem->flags != src_rmem->flags);
@@ -16169,6 +16174,7 @@ bnxt_queue_cfg_defaults(struct net_device *dev, int idx,
 }
 
 static const struct netdev_queue_mgmt_ops bnxt_queue_mgmt_ops = {
+	.supported_ring_params	= ETHTOOL_RING_USE_RX_BUF_LEN,
 	.ndo_queue_mem_size	= sizeof(struct bnxt_rx_ring_info),
 
 	.ndo_queue_cfg_defaults	= bnxt_queue_cfg_defaults,
-- 
2.49.0

[RFC v2 22/24] net: let pp memory provider to specify rx buf len

[Pavel Begunkov]

Allow memory providers to configure rx queues with a specific receive
buffer length. Pass it in sturct pp_memory_provider_params, which is
copied into the queue, and make __netdev_queue_config() to check if it's
present and apply to the configuration. This way the configured length
will persist across queue restarts, and will be automatically removed
once a memory provider is detached.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 include/net/page_pool/types.h |  1 +
 net/core/netdev_config.c      | 15 +++++++++++----
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/include/net/page_pool/types.h b/include/net/page_pool/types.h
index 431b593de709..e86bb471f1fc 100644
--- a/include/net/page_pool/types.h
+++ b/include/net/page_pool/types.h
@@ -161,6 +161,7 @@ struct memory_provider_ops;
 struct pp_memory_provider_params {
 	void *mp_priv;
 	const struct memory_provider_ops *mp_ops;
+	u32 rx_buf_len;
 };
 
 struct page_pool {
diff --git a/net/core/netdev_config.c b/net/core/netdev_config.c
index c5ae39e76f40..2c9b06f94e01 100644
--- a/net/core/netdev_config.c
+++ b/net/core/netdev_config.c
@@ -2,6 +2,7 @@
 
 #include <linux/netdevice.h>
 #include <net/netdev_queues.h>
+#include <net/netdev_rx_queue.h>
 
 #include "dev.h"
 
@@ -77,7 +78,7 @@ void netdev_queue_config_update_cnt(struct net_device *dev, unsigned int txq,
 	}
 }
 
-void __netdev_queue_config(struct net_device *dev, int rxq,
+void __netdev_queue_config(struct net_device *dev, int rxq_idx,
 			   struct netdev_queue_config *qcfg, bool pending)
 {
 	const struct netdev_config *cfg;
@@ -88,18 +89,24 @@ void __netdev_queue_config(struct net_device *dev, int rxq,
 
 	/* Get defaults from the driver, in case user config not set */
 	if (dev->queue_mgmt_ops->ndo_queue_cfg_defaults)
-		dev->queue_mgmt_ops->ndo_queue_cfg_defaults(dev, rxq, qcfg);
+		dev->queue_mgmt_ops->ndo_queue_cfg_defaults(dev, rxq_idx, qcfg);
 
 	/* Set config based on device-level settings */
 	if (cfg->rx_buf_len)
 		qcfg->rx_buf_len = cfg->rx_buf_len;
 
 	/* Set config dedicated to this queue */
-	if (rxq >= 0) {
-		const struct netdev_queue_config *user_cfg = &cfg->qcfg[rxq];
+	if (rxq_idx >= 0) {
+		const struct netdev_queue_config *user_cfg;
+		struct netdev_rx_queue *rxq;
 
+		user_cfg = &cfg->qcfg[rxq_idx];
 		if (user_cfg->rx_buf_len)
 			qcfg->rx_buf_len = user_cfg->rx_buf_len;
+
+		rxq = __netif_get_rx_queue(dev, rxq_idx);
+		if (rxq->mp_params.mp_ops && rxq->mp_params.rx_buf_len)
+			qcfg->rx_buf_len = rxq->mp_params.rx_buf_len;
 	}
 }
 
-- 
2.49.0

[RFC v2 23/24] net: validate driver supports passed qcfg params

[Pavel Begunkov]

When we pass a qcfg to a driver, make sure it supports the set
parameters by checking it against ->supported_ring_params.

Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 net/core/dev.h             |  3 +++
 net/core/netdev_config.c   | 26 ++++++++++++++++++++++++++
 net/core/netdev_rx_queue.c |  8 +++-----
 3 files changed, 32 insertions(+), 5 deletions(-)

diff --git a/net/core/dev.h b/net/core/dev.h
index a33d8a507bed..9e43da3856d7 100644
--- a/net/core/dev.h
+++ b/net/core/dev.h
@@ -103,6 +103,9 @@ int netdev_queue_config_revalidate(struct net_device *dev,
 				   struct netlink_ext_ack *extack);
 void netdev_queue_config_update_cnt(struct net_device *dev, unsigned int txq,
 				    unsigned int rxq);
+int netdev_queue_config_validate(struct net_device *dev, int rxq_idx,
+				  struct netdev_queue_config *qcfg,
+				  struct netlink_ext_ack *extack);
 
 /* netdev management, shared between various uAPI entry points */
 struct netdev_name_node {
diff --git a/net/core/netdev_config.c b/net/core/netdev_config.c
index 2c9b06f94e01..ffe997893cd1 100644
--- a/net/core/netdev_config.c
+++ b/net/core/netdev_config.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0-only
 
 #include <linux/netdevice.h>
+#include <linux/ethtool.h>
 #include <net/netdev_queues.h>
 #include <net/netdev_rx_queue.h>
 
@@ -136,6 +137,31 @@ void netdev_queue_config(struct net_device *dev, int rxq,
 }
 EXPORT_SYMBOL(netdev_queue_config);
 
+int netdev_queue_config_validate(struct net_device *dev, int rxq_idx,
+				  struct netdev_queue_config *qcfg,
+				  struct netlink_ext_ack *extack)
+{
+	const struct netdev_queue_mgmt_ops *qops = dev->queue_mgmt_ops;
+	int err;
+
+	if (WARN_ON_ONCE(!qops))
+		return -EINVAL;
+
+	if (!(qops->supported_ring_params & ETHTOOL_RING_USE_RX_BUF_LEN) &&
+	    qcfg->rx_buf_len &&
+	    qcfg->rx_buf_len != dev->cfg_pending->rx_buf_len) {
+		NL_SET_ERR_MSG_MOD(extack, "changing rx-buf-len not supported");
+		return -EINVAL;
+	}
+
+	if (qops->ndo_queue_cfg_validate) {
+		err = qops->ndo_queue_cfg_validate(dev, rxq_idx, qcfg, extack);
+		if (err)
+			return err;
+	}
+	return 0;
+}
+
 int netdev_queue_config_revalidate(struct net_device *dev,
 				   struct netlink_ext_ack *extack)
 {
diff --git a/net/core/netdev_rx_queue.c b/net/core/netdev_rx_queue.c
index 39834b196e95..d583a9ead9c4 100644
--- a/net/core/netdev_rx_queue.c
+++ b/net/core/netdev_rx_queue.c
@@ -37,11 +37,9 @@ int netdev_rx_queue_restart(struct net_device *dev, unsigned int rxq_idx,
 
 	netdev_queue_config(dev, rxq_idx, &qcfg);
 
-	if (qops->ndo_queue_cfg_validate) {
-		err = qops->ndo_queue_cfg_validate(dev, rxq_idx, &qcfg, extack);
-		if (err)
-			goto err_free_old_mem;
-	}
+	err = netdev_queue_config_validate(dev, rxq_idx, &qcfg, extack);
+	if (err)
+		goto err_free_old_mem;
 
 	err = qops->ndo_queue_mem_alloc(dev, &qcfg, new_mem, rxq_idx);
 	if (err)
-- 
2.49.0

[RFC v2 24/24] io_uring/zcrx: implement large rx buffer support

[Pavel Begunkov]

There are network cards that support receive buffers larger than 4K, and
that can be vastly beneficial for performance, and benchmarks for this
patch showed up to 30% CPU util improvement for 32K vs 4K buffers.

Allows zcrx users to specify the size in struct
io_uring_zcrx_ifq_reg::rx_buf_len. If set to zero, zcrx will use a
default value. zcrx will check and fail if the memory backing the area
can't be split into physically contiguous chunks of the required size.
It's more restrictive as it only needs dma addresses to be contig, but
that's beyond this series.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 include/uapi/linux/io_uring.h |  2 +-
 io_uring/zcrx.c               | 36 ++++++++++++++++++++++++++++++-----
 2 files changed, 32 insertions(+), 6 deletions(-)

diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index 9d306eb5251c..8e3a342a4ad8 100644
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -1041,7 +1041,7 @@ struct io_uring_zcrx_ifq_reg {
 
 	struct io_uring_zcrx_offsets offsets;
 	__u32	zcrx_id;
-	__u32	__resv2;
+	__u32	rx_buf_len;
 	__u64	__resv[3];
 };
 
diff --git a/io_uring/zcrx.c b/io_uring/zcrx.c
index 985c7386e24b..90597547d632 100644
--- a/io_uring/zcrx.c
+++ b/io_uring/zcrx.c
@@ -13,6 +13,7 @@
 #include <net/page_pool/memory_provider.h>
 #include <net/netlink.h>
 #include <net/netdev_rx_queue.h>
+#include <net/netdev_queues.h>
 #include <net/tcp.h>
 #include <net/rps.h>
 
@@ -53,6 +54,18 @@ static inline struct page *io_zcrx_iov_page(const struct net_iov *niov)
 	return area->mem.pages[net_iov_idx(niov) << niov_pages_shift];
 }
 
+static int io_area_max_shift(struct io_zcrx_mem *mem)
+{
+	struct sg_table *sgt = mem->sgt;
+	struct scatterlist *sg;
+	unsigned order = -1U;
+	unsigned i;
+
+	for_each_sgtable_dma_sg(sgt, sg, i)
+		order = min(order, __ffs(sg->length));
+	return order;
+}
+
 static int io_populate_area_dma(struct io_zcrx_ifq *ifq,
 				struct io_zcrx_area *area)
 {
@@ -384,8 +397,10 @@ static int io_zcrx_append_area(struct io_zcrx_ifq *ifq,
 }
 
 static int io_zcrx_create_area(struct io_zcrx_ifq *ifq,
-			       struct io_uring_zcrx_area_reg *area_reg)
+			       struct io_uring_zcrx_area_reg *area_reg,
+			       struct io_uring_zcrx_ifq_reg *reg)
 {
+	int buf_size_shift = PAGE_SHIFT;
 	struct io_zcrx_area *area;
 	unsigned nr_iovs;
 	int i, ret;
@@ -400,7 +415,16 @@ static int io_zcrx_create_area(struct io_zcrx_ifq *ifq,
 	if (ret)
 		goto err;
 
-	ifq->niov_shift = PAGE_SHIFT;
+	if (reg->rx_buf_len) {
+		if (!is_power_of_2(reg->rx_buf_len) ||
+		     reg->rx_buf_len < PAGE_SIZE)
+			return -EINVAL;
+		buf_size_shift = ilog2(reg->rx_buf_len);
+	}
+	if (buf_size_shift > io_area_max_shift(&area->mem))
+		return -EINVAL;
+
+	ifq->niov_shift = buf_size_shift;
 	nr_iovs = area->mem.size >> ifq->niov_shift;
 	area->nia.num_niovs = nr_iovs;
 
@@ -544,8 +568,7 @@ int io_register_zcrx_ifq(struct io_ring_ctx *ctx,
 		return -EFAULT;
 	if (copy_from_user(&rd, u64_to_user_ptr(reg.region_ptr), sizeof(rd)))
 		return -EFAULT;
-	if (!mem_is_zero(&reg.__resv, sizeof(reg.__resv)) ||
-	    reg.__resv2 || reg.zcrx_id)
+	if (!mem_is_zero(&reg.__resv, sizeof(reg.__resv)) || reg.zcrx_id)
 		return -EINVAL;
 	if (reg.if_rxq == -1 || !reg.rq_entries || reg.flags)
 		return -EINVAL;
@@ -589,12 +612,13 @@ int io_register_zcrx_ifq(struct io_ring_ctx *ctx,
 	}
 	get_device(ifq->dev);
 
-	ret = io_zcrx_create_area(ifq, &area);
+	ret = io_zcrx_create_area(ifq, &area, &reg);
 	if (ret)
 		goto err;
 
 	mp_param.mp_ops = &io_uring_pp_zc_ops;
 	mp_param.mp_priv = ifq;
+	mp_param.rx_buf_len = 1U << ifq->niov_shift;
 	ret = net_mp_open_rxq(ifq->netdev, reg.if_rxq, &mp_param);
 	if (ret)
 		goto err;
@@ -612,6 +636,8 @@ int io_register_zcrx_ifq(struct io_ring_ctx *ctx,
 			goto err;
 	}
 
+	reg.rx_buf_len = 1U << ifq->niov_shift;
+
 	if (copy_to_user(arg, &reg, sizeof(reg)) ||
 	    copy_to_user(u64_to_user_ptr(reg.region_ptr), &rd, sizeof(rd)) ||
 	    copy_to_user(u64_to_user_ptr(reg.area_ptr), &area, sizeof(area))) {
-- 
2.49.0

Re: [RFC v2 00/24] Per queue configs and large rx buffer support for zcrx

[Dragos Tatulea]

Hi Pavel,

On Fri, Aug 08, 2025 at 03:54:23PM +0100, Pavel Begunkov wrote:
> [...] 
> For example, for 200Gbit broadcom NIC, 4K vs 32K buffers, and napi and
> userspace pinned to the same CPU:
> 
> packets=23987040 (MB=2745098), rps=199559 (MB/s=22837)
> CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
>   0    1.53    0.00   27.78    2.72    1.31   66.45    0.22
> packets=24078368 (MB=2755550), rps=200319 (MB/s=22924)
> CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
>   0    0.69    0.00    8.26   31.65    1.83   57.00    0.57
> 
> And for napi and userspace on different CPUs:
> 
> packets=10725082 (MB=1227388), rps=198285 (MB/s=22692)
> CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
>   0    0.10    0.00    0.50    0.00    0.50   74.50    24.40
>   1    4.51    0.00   44.33   47.22    2.08    1.85    0.00
> packets=14026235 (MB=1605175), rps=198388 (MB/s=22703)
> CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
>   0    0.10    0.00    0.70    0.00    1.00   43.78   54.42
>   1    1.09    0.00   31.95   62.91    1.42    2.63    0.00
>
What did you use for this benchmark, send-zerocopy? Could you share a
branch and how you ran it please?

I have added some initial support to mlx5 for rx-buf-len and would like
to benchmark it and compare it to what you posted.

Thanks,
Dragos
 

Re: [RFC v2 00/24] Per queue configs and large rx buffer support for zcrx

[Pavel Begunkov]

On 8/13/25 16:39, Dragos Tatulea wrote:
> Hi Pavel,
> 
> On Fri, Aug 08, 2025 at 03:54:23PM +0100, Pavel Begunkov wrote:
>> [...]
>> For example, for 200Gbit broadcom NIC, 4K vs 32K buffers, and napi and
>> userspace pinned to the same CPU:
>>
>> packets=23987040 (MB=2745098), rps=199559 (MB/s=22837)
>> CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
>>    0    1.53    0.00   27.78    2.72    1.31   66.45    0.22
>> packets=24078368 (MB=2755550), rps=200319 (MB/s=22924)
>> CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
>>    0    0.69    0.00    8.26   31.65    1.83   57.00    0.57
>>
>> And for napi and userspace on different CPUs:
>>
>> packets=10725082 (MB=1227388), rps=198285 (MB/s=22692)
>> CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
>>    0    0.10    0.00    0.50    0.00    0.50   74.50    24.40
>>    1    4.51    0.00   44.33   47.22    2.08    1.85    0.00
>> packets=14026235 (MB=1605175), rps=198388 (MB/s=22703)
>> CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
>>    0    0.10    0.00    0.70    0.00    1.00   43.78   54.42
>>    1    1.09    0.00   31.95   62.91    1.42    2.63    0.00
>>
> What did you use for this benchmark, send-zerocopy? Could you share a
> branch and how you ran it please?
> 
> I have added some initial support to mlx5 for rx-buf-len and would like
> to benchmark it and compare it to what you posted.

You can use this branch:
https://github.com/isilence/liburing.git zcrx/rx-buf-len

# server
examples/zcrx -p <port> -q <queue_idx> -i <interface_name> -A1 \
              -B <rx_buf_len> -S <area size / memory provided>

"-A1" here is for using huge pages, so don't forget to configure
/proc/sys/vm/nr_hugepages.

# client
examples/send-zerocopy -6 tcp -D <ip addr> -p <port>
                        -t <runtime secs>
                        -l -b1 -n1 -z1 -d -s<send size>

I had to play with the client a bit for it to keep up with
the server. "-l" enables huge pages, and had to bump up the
send size. You can also add -v to both for a basic payload
verification.

-- 
Pavel Begunkov

Re: [RFC v2 00/24] Per queue configs and large rx buffer support for zcrx

[Dragos Tatulea]

On Thu, Aug 14, 2025 at 11:46:35AM +0100, Pavel Begunkov wrote:
> On 8/13/25 16:39, Dragos Tatulea wrote:
> > Hi Pavel,
> > 
> > On Fri, Aug 08, 2025 at 03:54:23PM +0100, Pavel Begunkov wrote:
> > > [...]
> > > For example, for 200Gbit broadcom NIC, 4K vs 32K buffers, and napi and
> > > userspace pinned to the same CPU:
> > > 
> > > packets=23987040 (MB=2745098), rps=199559 (MB/s=22837)
> > > CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
> > >    0    1.53    0.00   27.78    2.72    1.31   66.45    0.22
> > > packets=24078368 (MB=2755550), rps=200319 (MB/s=22924)
> > > CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
> > >    0    0.69    0.00    8.26   31.65    1.83   57.00    0.57
> > > 
> > > And for napi and userspace on different CPUs:
> > > 
> > > packets=10725082 (MB=1227388), rps=198285 (MB/s=22692)
> > > CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
> > >    0    0.10    0.00    0.50    0.00    0.50   74.50    24.40
> > >    1    4.51    0.00   44.33   47.22    2.08    1.85    0.00
> > > packets=14026235 (MB=1605175), rps=198388 (MB/s=22703)
> > > CPU    %usr   %nice    %sys %iowait    %irq   %soft   %idle
> > >    0    0.10    0.00    0.70    0.00    1.00   43.78   54.42
> > >    1    1.09    0.00   31.95   62.91    1.42    2.63    0.00
> > > 
I forgot to ask: what is the MTU here?

> > What did you use for this benchmark, send-zerocopy? Could you share a
> > branch and how you ran it please?
> > 
> > I have added some initial support to mlx5 for rx-buf-len and would like
> > to benchmark it and compare it to what you posted.
> 
> You can use this branch:
> https://github.com/isilence/liburing.git zcrx/rx-buf-len
> 
> # server
> examples/zcrx -p <port> -q <queue_idx> -i <interface_name> -A1 \
>              -B <rx_buf_len> -S <area size / memory provided>
>
> "-A1" here is for using huge pages, so don't forget to configure
> /proc/sys/vm/nr_hugepages.
> 
> # client
> examples/send-zerocopy -6 tcp -D <ip addr> -p <port>
>                        -t <runtime secs>
>                        -l -b1 -n1 -z1 -d -s<send size>
>
Thanks a lot for the branch and the instructions Pavel! I am playing
with them now and seeing some preliminary good results. Will post
them once we share the patches.

> I had to play with the client a bit for it to keep up with
> the server. "-l" enables huge pages, and had to bump up the
> send size. You can also add -v to both for a basic payload
> verification.
>
I see what you mean. I also had to make the rx memory larger once
rx-buf-len >= 32K. Otherwise the traffic was hanging after a second or
so. This is probably related to the currently known issue where if a
page_pool is too small due to incorrect sizing of the buffer, mlx5 hangs
on first refill. That still needs fixing.

Thanks,
Dragos

Re: [RFC v2 00/24] Per queue configs and large rx buffer support for zcrx

[Pavel Begunkov]

On 8/15/25 17:44, Dragos Tatulea wrote:
> On Thu, Aug 14, 2025 at 11:46:35AM +0100, Pavel Begunkov wrote:
...>> "-A1" here is for using huge pages, so don't forget to configure
>> /proc/sys/vm/nr_hugepages.
>>
>> # client
>> examples/send-zerocopy -6 tcp -D <ip addr> -p <port>
>>                         -t <runtime secs>
>>                         -l -b1 -n1 -z1 -d -s<send size>
>>
> Thanks a lot for the branch and the instructions Pavel! I am playing
> with them now and seeing some preliminary good results. Will post
> them once we share the patches.

Sounds good

>> I had to play with the client a bit for it to keep up with
>> the server. "-l" enables huge pages, and had to bump up the
>> send size. You can also add -v to both for a basic payload
>> verification.
>>
> I see what you mean. I also had to make the rx memory larger once

Forgot to mention that the tool doesn't consider CPU affinities,
so I had to configure task and irq affinities by hand.

> rx-buf-len >= 32K. Otherwise the traffic was hanging after a second or
> so. This is probably related to the currently known issue where if a
> page_pool is too small due to incorrect sizing of the buffer, mlx5 hangs
> on first refill. That still needs fixing.

-- 
Pavel Begunkov