Re: [PATCH net-next, 4/6] net/mlx5: Add HV VHCA infrastructure

From: Mark Bloch
Date: Wed Aug 14 2019 - 16:42:25 EST




On 8/14/19 12:08 PM, Haiyang Zhang wrote:
> From: Eran Ben Elisha <eranbe@xxxxxxxxxxxx>
>
> HV VHCA is a layer which provides PF to VF communication channel based on
> HyperV PCI config channel. It implements Mellanox's Inter VHCA control
> communication protocol. The protocol contains control block in order to
> pass messages between the PF and VF drivers, and data blocks in order to
> pass actual data.
>
> The infrastructure is agent based. Each agent will be responsible of
> contiguous buffer blocks in the VHCA config space. This infrastructure will
> bind agents to their blocks, and those agents can only access read/write
> the buffer blocks assigned to them. Each agent will provide three
> callbacks (control, invalidate, cleanup). Control will be invoked when
> block-0 is invalidated with a command that concerns this agent. Invalidate
> callback will be invoked if one of the blocks assigned to this agent was
> invalidated. Cleanup will be invoked before the agent is being freed in
> order to clean all of its open resources or deferred works.
>
> Block-0 serves as the control block. All execution commands from the PF
> will be written by the PF over this block. VF will ack on those by
> writing on block-0 as well. Its format is described by struct
> mlx5_hv_vhca_control_block layout.
>
> Signed-off-by: Eran Ben Elisha <eranbe@xxxxxxxxxxxx>
> Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx>
> ---
> drivers/net/ethernet/mellanox/mlx5/core/Makefile | 2 +-
> .../net/ethernet/mellanox/mlx5/core/lib/hv_vhca.c | 247 +++++++++++++++++++++
> .../net/ethernet/mellanox/mlx5/core/lib/hv_vhca.h | 102 +++++++++
> drivers/net/ethernet/mellanox/mlx5/core/main.c | 7 +
> include/linux/mlx5/driver.h | 2 +
> 5 files changed, 359 insertions(+), 1 deletion(-)
> create mode 100644 drivers/net/ethernet/mellanox/mlx5/core/lib/hv_vhca.c
> create mode 100644 drivers/net/ethernet/mellanox/mlx5/core/lib/hv_vhca.h
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/Makefile b/drivers/net/ethernet/mellanox/mlx5/core/Makefile
> index a8950b1..e0a1056 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/Makefile
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/Makefile
> @@ -45,7 +45,7 @@ mlx5_core-$(CONFIG_MLX5_ESWITCH) += eswitch.o eswitch_offloads.o eswitch_offlo
> mlx5_core-$(CONFIG_MLX5_MPFS) += lib/mpfs.o
> mlx5_core-$(CONFIG_VXLAN) += lib/vxlan.o
> mlx5_core-$(CONFIG_PTP_1588_CLOCK) += lib/clock.o
> -mlx5_core-$(CONFIG_PCI_HYPERV_MINI) += lib/hv.o
> +mlx5_core-$(CONFIG_PCI_HYPERV_MINI)+= lib/hv.o lib/hv_vhca.o
>
> #
> # Ipoib netdev
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/hv_vhca.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/hv_vhca.c
> new file mode 100644
> index 0000000..b2eebdf
> --- /dev/null
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/hv_vhca.c
> @@ -0,0 +1,247 @@
> +// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
> +// Copyright (c) 2018 Mellanox Technologies
> +
> +#include <linux/hyperv.h>
> +#include "mlx5_core.h"
> +#include "lib/hv.h"
> +#include "lib/hv_vhca.h"
> +
> +struct mlx5_hv_vhca {
> + struct mlx5_core_dev *dev;
> + struct workqueue_struct *work_queue;
> + struct mlx5_hv_vhca_agent *agents[MLX5_HV_VHCA_AGENT_MAX];
> + struct mutex agents_lock; /* Protect agents array */
> +};
> +
> +struct mlx5_hv_vhca_work {
> + struct work_struct invalidate_work;
> + struct mlx5_hv_vhca *hv_vhca;
> + u64 block_mask;
> +};
> +
> +struct mlx5_hv_vhca_data_block {
> + u16 sequence;
> + u16 offset;
> + u8 reserved[4];
> + u64 data[15];
> +};
> +
> +struct mlx5_hv_vhca_agent {
> + enum mlx5_hv_vhca_agent_type type;
> + struct mlx5_hv_vhca *hv_vhca;
> + void *priv;
> + int seq;
Why is this int? and in data block is u16?

> + void (*control)(struct mlx5_hv_vhca_agent *agent,
> + struct mlx5_hv_vhca_control_block *block);
> + void (*invalidate)(struct mlx5_hv_vhca_agent *agent,
> + u64 block_mask);
> + void (*cleanup)(struct mlx5_hv_vhca_agent *agent);
> +};
> +
> +struct mlx5_hv_vhca *mlx5_hv_vhca_create(struct mlx5_core_dev *dev)
> +{
> + struct mlx5_hv_vhca *hv_vhca = NULL;
> +
> + hv_vhca = kzalloc(sizeof(*hv_vhca), GFP_KERNEL);
> + if (!hv_vhca)
> + return ERR_PTR(-ENOMEM);
> +
> + hv_vhca->work_queue = create_singlethread_workqueue("mlx5_hv_vhca");
> + if (!hv_vhca->work_queue) {
> + kfree(hv_vhca);
> + return ERR_PTR(-ENOMEM);
> + }
> +
> + hv_vhca->dev = dev;
> + mutex_init(&hv_vhca->agents_lock);
> +
> + return hv_vhca;
> +}
> +
> +void mlx5_hv_vhca_destroy(struct mlx5_hv_vhca *hv_vhca)
> +{
> + if (IS_ERR_OR_NULL(hv_vhca))
> + return;
> +
> + flush_workqueue(hv_vhca->work_queue);
> + destroy_workqueue(hv_vhca->work_queue);

Why not just destroy?

> + kfree(hv_vhca);
> +}
> +
> +static void mlx5_hv_vhca_invalidate_work(struct work_struct *work)
> +{
> + struct mlx5_hv_vhca_work *hwork;
> + struct mlx5_hv_vhca *hv_vhca;
> + int i;
> +
> + hwork = container_of(work, struct mlx5_hv_vhca_work, invalidate_work);
> + hv_vhca = hwork->hv_vhca;
> +
> + mutex_lock(&hv_vhca->agents_lock);
> + for (i = 0; i < MLX5_HV_VHCA_AGENT_MAX; i++) {
> + struct mlx5_hv_vhca_agent *agent = hv_vhca->agents[i];
> +
> + if (!agent || !agent->invalidate)
> + continue;
> +
> + if (!(BIT(agent->type) & hwork->block_mask))
> + continue;
> +
> + agent->invalidate(agent, hwork->block_mask);
> + }
> + mutex_unlock(&hv_vhca->agents_lock);
> +
> + kfree(hwork);
> +}
> +
> +void mlx5_hv_vhca_invalidate(void *context, u64 block_mask)
> +{
> + struct mlx5_hv_vhca *hv_vhca = (struct mlx5_hv_vhca *)context;
> + struct mlx5_hv_vhca_work *work;
> +
> + work = kzalloc(sizeof(*work), GFP_ATOMIC);
> + if (!work)
> + return;
> +
> + INIT_WORK(&work->invalidate_work, mlx5_hv_vhca_invalidate_work);
> + work->hv_vhca = hv_vhca;
> + work->block_mask = block_mask;
> +
> + queue_work(hv_vhca->work_queue, &work->invalidate_work);
> +}
> +
> +int mlx5_hv_vhca_init(struct mlx5_hv_vhca *hv_vhca)
> +{
> + if (IS_ERR_OR_NULL(hv_vhca))
> + return IS_ERR_OR_NULL(hv_vhca);
> +
> + return mlx5_hv_register_invalidate(hv_vhca->dev, hv_vhca,
> + mlx5_hv_vhca_invalidate);
> +}
> +
> +void mlx5_hv_vhca_cleanup(struct mlx5_hv_vhca *hv_vhca)
> +{
> + int i;
> +
> + if (IS_ERR_OR_NULL(hv_vhca))
> + return;
> +
> + mutex_lock(&hv_vhca->agents_lock);
> + for (i = 0; i < MLX5_HV_VHCA_AGENT_MAX; i++)
> + WARN_ON(hv_vhca->agents[i]);
> +
> + mutex_unlock(&hv_vhca->agents_lock);
> +
> + mlx5_hv_unregister_invalidate(hv_vhca->dev);
> +}
> +
> +struct mlx5_hv_vhca_agent *
> +mlx5_hv_vhca_agent_create(struct mlx5_hv_vhca *hv_vhca,
> + enum mlx5_hv_vhca_agent_type type,
> + void (*control)(struct mlx5_hv_vhca_agent*,
> + struct mlx5_hv_vhca_control_block *block),
> + void (*invalidate)(struct mlx5_hv_vhca_agent*,
> + u64 block_mask),
> + void (*cleaup)(struct mlx5_hv_vhca_agent *agent),
> + void *priv)
> +{
> + struct mlx5_hv_vhca_agent *agent;
> +
> + if (IS_ERR_OR_NULL(hv_vhca))
> + return ERR_PTR(-ENOMEM);
> +
> + if (hv_vhca->agents[type])
> + return ERR_PTR(-EINVAL);> +
> + agent = kzalloc(sizeof(*agent), GFP_KERNEL);
> + if (!agent)
> + return ERR_PTR(-ENOMEM);
> +
> + agent->type = type;
> + agent->hv_vhca = hv_vhca;
> + agent->priv = priv;
> + agent->control = control;
> + agent->invalidate = invalidate;
> + agent->cleanup = cleaup;
> +
> + mutex_lock(&hv_vhca->agents_lock);
> + hv_vhca->agents[type] = agent;
> + mutex_unlock(&hv_vhca->agents_lock);

You have a check for this not under a lock a few lines up,
but assign under a lock?

Mark

> +
> + return agent;
> +}
> +
> +void mlx5_hv_vhca_agent_destroy(struct mlx5_hv_vhca_agent *agent)
> +{
> + struct mlx5_hv_vhca *hv_vhca = agent->hv_vhca;
> +
> + mutex_lock(&hv_vhca->agents_lock);
> +
> + if (WARN_ON(agent != hv_vhca->agents[agent->type])) {
> + mutex_unlock(&hv_vhca->agents_lock);
> + return;
> + }
> +
> + hv_vhca->agents[agent->type] = NULL;
> + mutex_unlock(&hv_vhca->agents_lock);
> +
> + if (agent->cleanup)
> + agent->cleanup(agent);
> +
> + kfree(agent);
> +}
> +
> +static int mlx5_hv_vhca_data_block_prepare(struct mlx5_hv_vhca_agent *agent,
> + struct mlx5_hv_vhca_data_block *data_block,
> + void *src, int len, int *offset)
> +{
> + int bytes = min_t(int, (int)sizeof(data_block->data), len);
> +
> + data_block->sequence = agent->seq;
> + data_block->offset = (*offset)++;
> + memcpy(data_block->data, src, bytes);
> +
> + return bytes;
> +}
> +
> +static void mlx5_hv_vhca_agent_seq_update(struct mlx5_hv_vhca_agent *agent)
> +{
> + agent->seq++;
> +}
> +
> +int mlx5_hv_vhca_agent_write(struct mlx5_hv_vhca_agent *agent,
> + void *buf, int len)
> +{
> + int offset = agent->type * HV_CONFIG_BLOCK_SIZE_MAX;
> + int block_offset = 0;
> + int total = 0;
> + int err;
> +
> + while (len) {
> + struct mlx5_hv_vhca_data_block data_block = {0};
> + int bytes;
> +
> + bytes = mlx5_hv_vhca_data_block_prepare(agent, &data_block,
> + buf + total,
> + len, &block_offset);
> + if (!bytes)
> + return -ENOMEM;
> +
> + err = mlx5_hv_write_config(agent->hv_vhca->dev, &data_block,
> + sizeof(data_block), offset);
> + if (err)
> + return err;
> +
> + total += bytes;
> + len -= bytes;
> + }
> +
> + mlx5_hv_vhca_agent_seq_update(agent);
> +
> + return 0;
> +}
> +
> +void *mlx5_hv_vhca_agent_priv(struct mlx5_hv_vhca_agent *agent)
> +{
> + return agent->priv;
> +}
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/hv_vhca.h b/drivers/net/ethernet/mellanox/mlx5/core/lib/hv_vhca.h
> new file mode 100644
> index 0000000..fa7ee85
> --- /dev/null
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/hv_vhca.h
> @@ -0,0 +1,102 @@
> +/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
> +/* Copyright (c) 2019 Mellanox Technologies. */
> +
> +#ifndef __LIB_HV_VHCA_H__
> +#define __LIB_HV_VHCA_H__
> +
> +#include "en.h"
> +#include "lib/hv.h"
> +
> +struct mlx5_hv_vhca_agent;
> +struct mlx5_hv_vhca;
> +struct mlx5_hv_vhca_control_block;
> +
> +enum mlx5_hv_vhca_agent_type {
> + MLX5_HV_VHCA_AGENT_MAX = 32,
> +};
> +
> +#if IS_ENABLED(CONFIG_PCI_HYPERV_MINI)
> +
> +struct mlx5_hv_vhca_control_block {
> + u32 capabilities;
> + u32 control;
> + u16 command;
> + u16 command_ack;
> + u16 version;
> + u16 rings;
> + u32 reserved1[28];
> +};
> +
> +struct mlx5_hv_vhca *mlx5_hv_vhca_create(struct mlx5_core_dev *dev);
> +void mlx5_hv_vhca_destroy(struct mlx5_hv_vhca *hv_vhca);
> +int mlx5_hv_vhca_init(struct mlx5_hv_vhca *hv_vhca);
> +void mlx5_hv_vhca_cleanup(struct mlx5_hv_vhca *hv_vhca);
> +void mlx5_hv_vhca_invalidate(void *context, u64 block_mask);
> +
> +struct mlx5_hv_vhca_agent *
> +mlx5_hv_vhca_agent_create(struct mlx5_hv_vhca *hv_vhca,
> + enum mlx5_hv_vhca_agent_type type,
> + void (*control)(struct mlx5_hv_vhca_agent*,
> + struct mlx5_hv_vhca_control_block *block),
> + void (*invalidate)(struct mlx5_hv_vhca_agent*,
> + u64 block_mask),
> + void (*cleanup)(struct mlx5_hv_vhca_agent *agent),
> + void *context);
> +
> +void mlx5_hv_vhca_agent_destroy(struct mlx5_hv_vhca_agent *agent);
> +int mlx5_hv_vhca_agent_write(struct mlx5_hv_vhca_agent *agent,
> + void *buf, int len);
> +void *mlx5_hv_vhca_agent_priv(struct mlx5_hv_vhca_agent *agent);
> +
> +#else
> +
> +static inline struct mlx5_hv_vhca *
> +mlx5_hv_vhca_create(struct mlx5_core_dev *dev)
> +{
> + return NULL;
> +}
> +
> +static inline void mlx5_hv_vhca_destroy(struct mlx5_hv_vhca *hv_vhca)
> +{
> +}
> +
> +static inline int mlx5_hv_vhca_init(struct mlx5_hv_vhca *hv_vhca)
> +{
> + return 0;
> +}
> +
> +static inline void mlx5_hv_vhca_cleanup(struct mlx5_hv_vhca *hv_vhca)
> +{
> +}
> +
> +static inline void mlx5_hv_vhca_invalidate(void *context,
> + u64 block_mask)
> +{
> +}
> +
> +static inline struct mlx5_hv_vhca_agent *
> +mlx5_hv_vhca_agent_create(struct mlx5_hv_vhca *hv_vhca,
> + enum mlx5_hv_vhca_agent_type type,
> + void (*control)(struct mlx5_hv_vhca_agent*,
> + struct mlx5_hv_vhca_control_block *block),
> + void (*invalidate)(struct mlx5_hv_vhca_agent*,
> + u64 block_mask),
> + void (*cleanup)(struct mlx5_hv_vhca_agent *agent),
> + void *context)
> +{
> + return NULL;
> +}
> +
> +static inline void mlx5_hv_vhca_agent_destroy(struct mlx5_hv_vhca_agent *agent)
> +{
> +}
> +
> +static inline int
> +mlx5_hv_vhca_write_agent(struct mlx5_hv_vhca_agent *agent,
> + void *buf, int len)
> +{
> + return 0;
> +}
> +#endif
> +
> +#endif /* __LIB_HV_VHCA_H__ */
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/main.c b/drivers/net/ethernet/mellanox/mlx5/core/main.c
> index 4cc90eb..50ee38b 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/main.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/main.c
> @@ -69,6 +69,7 @@
> #include "lib/pci_vsc.h"
> #include "diag/fw_tracer.h"
> #include "ecpf.h"
> +#include "lib/hv_vhca.h"
>
> MODULE_AUTHOR("Eli Cohen <eli@xxxxxxxxxxxx>");
> MODULE_DESCRIPTION("Mellanox 5th generation network adapters (ConnectX series) core driver");
> @@ -872,6 +873,7 @@ static int mlx5_init_once(struct mlx5_core_dev *dev)
> }
>
> dev->tracer = mlx5_fw_tracer_create(dev);
> + dev->hv_vhca = mlx5_hv_vhca_create(dev);
>
> return 0;
>
> @@ -902,6 +904,7 @@ static int mlx5_init_once(struct mlx5_core_dev *dev)
>
> static void mlx5_cleanup_once(struct mlx5_core_dev *dev)
> {
> + mlx5_hv_vhca_destroy(dev->hv_vhca);
> mlx5_fw_tracer_destroy(dev->tracer);
> mlx5_fpga_cleanup(dev);
> mlx5_eswitch_cleanup(dev->priv.eswitch);
> @@ -1068,6 +1071,8 @@ static int mlx5_load(struct mlx5_core_dev *dev)
> goto err_fw_tracer;
> }
>
> + mlx5_hv_vhca_init(dev->hv_vhca);
> +
> err = mlx5_fpga_device_start(dev);
> if (err) {
> mlx5_core_err(dev, "fpga device start failed %d\n", err);
> @@ -1123,6 +1128,7 @@ static int mlx5_load(struct mlx5_core_dev *dev)
> err_ipsec_start:
> mlx5_fpga_device_stop(dev);
> err_fpga_start:
> + mlx5_hv_vhca_cleanup(dev->hv_vhca);
> mlx5_fw_tracer_cleanup(dev->tracer);
> err_fw_tracer:
> mlx5_eq_table_destroy(dev);
> @@ -1143,6 +1149,7 @@ static void mlx5_unload(struct mlx5_core_dev *dev)
> mlx5_accel_ipsec_cleanup(dev);
> mlx5_accel_tls_cleanup(dev);
> mlx5_fpga_device_stop(dev);
> + mlx5_hv_vhca_cleanup(dev->hv_vhca);
> mlx5_fw_tracer_cleanup(dev->tracer);
> mlx5_eq_table_destroy(dev);
> mlx5_irq_table_destroy(dev);
> diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h
> index 2b84ee9..97bb98c 100644
> --- a/include/linux/mlx5/driver.h
> +++ b/include/linux/mlx5/driver.h
> @@ -646,6 +646,7 @@ struct mlx5_clock {
> struct mlx5_fw_tracer;
> struct mlx5_vxlan;
> struct mlx5_geneve;
> +struct mlx5_hv_vhca;
>
> struct mlx5_core_dev {
> struct device *device;
> @@ -693,6 +694,7 @@ struct mlx5_core_dev {
> struct mlx5_ib_clock_info *clock_info;
> struct mlx5_fw_tracer *tracer;
> u32 vsc_addr;
> + struct mlx5_hv_vhca *hv_vhca;
> };
>
> struct mlx5_db {
>