Re: [PATCH 01/19] hw/cxl/mbox: Pull the payload out of struct cxl_cmd and make instances constant

[Fan Ni <fan.ni@samsung.com>]

On Mon, Sep 25, 2023 at 05:11:06PM +0100, Jonathan Cameron wrote:
> Putting the pointer in the structure for command handling puts a single
> variable element inside an otherwise constant structure. Move it out as
> a directly passed variable and take the cxl_cmd structures constant.
> 
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> ---

Reviewed-by: Fan Ni <fan.ni@samsung.com>

>  include/hw/cxl/cxl_device.h |  13 ++++
>  hw/cxl/cxl-mailbox-utils.c  | 121 +++++++++++++++++++-----------------
>  2 files changed, 78 insertions(+), 56 deletions(-)
> 
> diff --git a/include/hw/cxl/cxl_device.h b/include/hw/cxl/cxl_device.h
> index 007ddaf078..556953469c 100644
> --- a/include/hw/cxl/cxl_device.h
> +++ b/include/hw/cxl/cxl_device.h
> @@ -111,6 +111,18 @@ typedef enum {
>      CXL_MBOX_MAX = 0x17
>  } CXLRetCode;
>  
> +typedef struct cxl_device_state CXLDeviceState;
> +struct cxl_cmd;
> +typedef CXLRetCode (*opcode_handler)(const struct cxl_cmd *cmd,
> +                                     uint8_t *payload,
> +                                     CXLDeviceState *cxl_dstate, uint16_t *len);
> +struct cxl_cmd {
> +    const char *name;
> +    opcode_handler handler;
> +    ssize_t in;
> +    uint16_t effect; /* Reported in CEL */
> +};
> +
>  typedef struct CXLEvent {
>      CXLEventRecordRaw data;
>      QSIMPLEQ_ENTRY(CXLEvent) node;
> @@ -178,6 +190,7 @@ typedef struct cxl_device_state {
>      uint64_t pmem_size;
>      uint64_t vmem_size;
>  
> +    const struct cxl_cmd (*cxl_cmd_set)[256];
>      CXLEventLog event_logs[CXL_EVENT_TYPE_MAX];
>  } CXLDeviceState;
>  
> diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c
> index ab082ec9de..c02de06943 100644
> --- a/hw/cxl/cxl-mailbox-utils.c
> +++ b/hw/cxl/cxl-mailbox-utils.c
> @@ -69,18 +69,9 @@ enum {
>          #define CLEAR_POISON           0x2
>  };
>  
> -struct cxl_cmd;
> -typedef CXLRetCode (*opcode_handler)(struct cxl_cmd *cmd,
> -                                   CXLDeviceState *cxl_dstate, uint16_t *len);
> -struct cxl_cmd {
> -    const char *name;
> -    opcode_handler handler;
> -    ssize_t in;
> -    uint16_t effect; /* Reported in CEL */
> -    uint8_t *payload;
> -};
>  
> -static CXLRetCode cmd_events_get_records(struct cxl_cmd *cmd,
> +static CXLRetCode cmd_events_get_records(const struct cxl_cmd *cmd,
> +                                         uint8_t *payload,
>                                           CXLDeviceState *cxlds,
>                                           uint16_t *len)
>  {
> @@ -92,9 +83,9 @@ static CXLRetCode cmd_events_get_records(struct cxl_cmd *cmd,
>          return CXL_MBOX_INVALID_INPUT;
>      }
>  
> -    log_type = *((uint8_t *)cmd->payload);
> +    log_type = payload[0];
>  
> -    pl = (CXLGetEventPayload *)cmd->payload;
> +    pl = (CXLGetEventPayload *)payload;
>      memset(pl, 0, sizeof(*pl));
>  
>      max_recs = (cxlds->payload_size - CXL_EVENT_PAYLOAD_HDR_SIZE) /
> @@ -106,25 +97,27 @@ static CXLRetCode cmd_events_get_records(struct cxl_cmd *cmd,
>      return cxl_event_get_records(cxlds, pl, log_type, max_recs, len);
>  }
>  
> -static CXLRetCode cmd_events_clear_records(struct cxl_cmd *cmd,
> +static CXLRetCode cmd_events_clear_records(const struct cxl_cmd *cmd,
> +                                           uint8_t *payload,
>                                             CXLDeviceState *cxlds,
>                                             uint16_t *len)
>  {
>      CXLClearEventPayload *pl;
>  
> -    pl = (CXLClearEventPayload *)cmd->payload;
> +    pl = (CXLClearEventPayload *)payload;
>      *len = 0;
>      return cxl_event_clear_records(cxlds, pl);
>  }
>  
> -static CXLRetCode cmd_events_get_interrupt_policy(struct cxl_cmd *cmd,
> +static CXLRetCode cmd_events_get_interrupt_policy(const struct cxl_cmd *cmd,
> +                                                  uint8_t *payload,
>                                                    CXLDeviceState *cxlds,
>                                                    uint16_t *len)
>  {
>      CXLEventInterruptPolicy *policy;
>      CXLEventLog *log;
>  
> -    policy = (CXLEventInterruptPolicy *)cmd->payload;
> +    policy = (CXLEventInterruptPolicy *)payload;
>      memset(policy, 0, sizeof(*policy));
>  
>      log = &cxlds->event_logs[CXL_EVENT_TYPE_INFO];
> @@ -157,7 +150,8 @@ static CXLRetCode cmd_events_get_interrupt_policy(struct cxl_cmd *cmd,
>      return CXL_MBOX_SUCCESS;
>  }
>  
> -static CXLRetCode cmd_events_set_interrupt_policy(struct cxl_cmd *cmd,
> +static CXLRetCode cmd_events_set_interrupt_policy(const struct cxl_cmd *cmd,
> +                                                  uint8_t *payload,
>                                                    CXLDeviceState *cxlds,
>                                                    uint16_t *len)
>  {
> @@ -168,7 +162,7 @@ static CXLRetCode cmd_events_set_interrupt_policy(struct cxl_cmd *cmd,
>          return CXL_MBOX_INVALID_PAYLOAD_LENGTH;
>      }
>  
> -    policy = (CXLEventInterruptPolicy *)cmd->payload;
> +    policy = (CXLEventInterruptPolicy *)payload;
>  
>      log = &cxlds->event_logs[CXL_EVENT_TYPE_INFO];
>      log->irq_enabled = (policy->info_settings & CXL_EVENT_INT_MODE_MASK) ==
> @@ -200,7 +194,8 @@ static CXLRetCode cmd_events_set_interrupt_policy(struct cxl_cmd *cmd,
>  }
>  
>  /* 8.2.9.2.1 */
> -static CXLRetCode cmd_firmware_update_get_info(struct cxl_cmd *cmd,
> +static CXLRetCode cmd_firmware_update_get_info(const struct cxl_cmd *cmd,
> +                                               uint8_t *payload,
>                                                 CXLDeviceState *cxl_dstate,
>                                                 uint16_t *len)
>  {
> @@ -221,7 +216,7 @@ static CXLRetCode cmd_firmware_update_get_info(struct cxl_cmd *cmd,
>          return CXL_MBOX_INTERNAL_ERROR;
>      }
>  
> -    fw_info = (void *)cmd->payload;
> +    fw_info = (void *)payload;
>      memset(fw_info, 0, sizeof(*fw_info));
>  
>      fw_info->slots_supported = 2;
> @@ -234,27 +229,29 @@ static CXLRetCode cmd_firmware_update_get_info(struct cxl_cmd *cmd,
>  }
>  
>  /* 8.2.9.3.1 */
> -static CXLRetCode cmd_timestamp_get(struct cxl_cmd *cmd,
> +static CXLRetCode cmd_timestamp_get(const struct cxl_cmd *cmd,
> +                                    uint8_t *payload,
>                                      CXLDeviceState *cxl_dstate,
>                                      uint16_t *len)
>  {
>      uint64_t final_time = cxl_device_get_timestamp(cxl_dstate);
>  
> -    stq_le_p(cmd->payload, final_time);
> +    stq_le_p(payload, final_time);
>      *len = 8;
>  
>      return CXL_MBOX_SUCCESS;
>  }
>  
>  /* 8.2.9.3.2 */
> -static CXLRetCode cmd_timestamp_set(struct cxl_cmd *cmd,
> -                                  CXLDeviceState *cxl_dstate,
> -                                  uint16_t *len)
> +static CXLRetCode cmd_timestamp_set(const struct cxl_cmd *cmd,
> +                                    uint8_t *payload,
> +                                    CXLDeviceState *cxl_dstate,
> +                                    uint16_t *len)
>  {
>      cxl_dstate->timestamp.set = true;
>      cxl_dstate->timestamp.last_set = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL);
>  
> -    cxl_dstate->timestamp.host_set = le64_to_cpu(*(uint64_t *)cmd->payload);
> +    cxl_dstate->timestamp.host_set = le64_to_cpu(*(uint64_t *)payload);
>  
>      *len = 0;
>      return CXL_MBOX_SUCCESS;
> @@ -267,7 +264,8 @@ static const QemuUUID cel_uuid = {
>  };
>  
>  /* 8.2.9.4.1 */
> -static CXLRetCode cmd_logs_get_supported(struct cxl_cmd *cmd,
> +static CXLRetCode cmd_logs_get_supported(const struct cxl_cmd *cmd,
> +                                         uint8_t *payload,
>                                           CXLDeviceState *cxl_dstate,
>                                           uint16_t *len)
>  {
> @@ -278,7 +276,7 @@ static CXLRetCode cmd_logs_get_supported(struct cxl_cmd *cmd,
>              QemuUUID uuid;
>              uint32_t size;
>          } log_entries[1];
> -    } QEMU_PACKED *supported_logs = (void *)cmd->payload;
> +    } QEMU_PACKED *supported_logs = (void *)payload;
>      QEMU_BUILD_BUG_ON(sizeof(*supported_logs) != 0x1c);
>  
>      supported_logs->entries = 1;
> @@ -290,7 +288,8 @@ static CXLRetCode cmd_logs_get_supported(struct cxl_cmd *cmd,
>  }
>  
>  /* 8.2.9.4.2 */
> -static CXLRetCode cmd_logs_get_log(struct cxl_cmd *cmd,
> +static CXLRetCode cmd_logs_get_log(const struct cxl_cmd *cmd,
> +                                   uint8_t *payload,
>                                     CXLDeviceState *cxl_dstate,
>                                     uint16_t *len)
>  {
> @@ -298,7 +297,9 @@ static CXLRetCode cmd_logs_get_log(struct cxl_cmd *cmd,
>          QemuUUID uuid;
>          uint32_t offset;
>          uint32_t length;
> -    } QEMU_PACKED QEMU_ALIGNED(16) *get_log = (void *)cmd->payload;
> +    } QEMU_PACKED QEMU_ALIGNED(16) *get_log;
> +
> +    get_log = (void *)payload;
>  
>      /*
>       * 8.2.9.4.2
> @@ -324,14 +325,15 @@ static CXLRetCode cmd_logs_get_log(struct cxl_cmd *cmd,
>      /* Store off everything to local variables so we can wipe out the payload */
>      *len = get_log->length;
>  
> -    memmove(cmd->payload, cxl_dstate->cel_log + get_log->offset,
> +    memmove(payload, cxl_dstate->cel_log + get_log->offset,
>             get_log->length);
>  
>      return CXL_MBOX_SUCCESS;
>  }
>  
>  /* 8.2.9.5.1.1 */
> -static CXLRetCode cmd_identify_memory_device(struct cxl_cmd *cmd,
> +static CXLRetCode cmd_identify_memory_device(const struct cxl_cmd *cmd,
> +                                             uint8_t *payload,
>                                               CXLDeviceState *cxl_dstate,
>                                               uint16_t *len)
>  {
> @@ -361,7 +363,7 @@ static CXLRetCode cmd_identify_memory_device(struct cxl_cmd *cmd,
>          return CXL_MBOX_INTERNAL_ERROR;
>      }
>  
> -    id = (void *)cmd->payload;
> +    id = (void *)payload;
>      memset(id, 0, sizeof(*id));
>  
>      snprintf(id->fw_revision, 0x10, "BWFW VERSION %02d", 0);
> @@ -382,7 +384,8 @@ static CXLRetCode cmd_identify_memory_device(struct cxl_cmd *cmd,
>      return CXL_MBOX_SUCCESS;
>  }
>  
> -static CXLRetCode cmd_ccls_get_partition_info(struct cxl_cmd *cmd,
> +static CXLRetCode cmd_ccls_get_partition_info(const struct cxl_cmd *cmd,
> +                                              uint8_t *payload,
>                                                CXLDeviceState *cxl_dstate,
>                                                uint16_t *len)
>  {
> @@ -391,7 +394,7 @@ static CXLRetCode cmd_ccls_get_partition_info(struct cxl_cmd *cmd,
>          uint64_t active_pmem;
>          uint64_t next_vmem;
>          uint64_t next_pmem;
> -    } QEMU_PACKED *part_info = (void *)cmd->payload;
> +    } QEMU_PACKED *part_info = (void *)payload;
>      QEMU_BUILD_BUG_ON(sizeof(*part_info) != 0x20);
>  
>      if ((!QEMU_IS_ALIGNED(cxl_dstate->vmem_size, CXL_CAPACITY_MULTIPLIER)) ||
> @@ -414,7 +417,8 @@ static CXLRetCode cmd_ccls_get_partition_info(struct cxl_cmd *cmd,
>      return CXL_MBOX_SUCCESS;
>  }
>  
> -static CXLRetCode cmd_ccls_get_lsa(struct cxl_cmd *cmd,
> +static CXLRetCode cmd_ccls_get_lsa(const struct cxl_cmd *cmd,
> +                                   uint8_t *payload,
>                                     CXLDeviceState *cxl_dstate,
>                                     uint16_t *len)
>  {
> @@ -426,7 +430,7 @@ static CXLRetCode cmd_ccls_get_lsa(struct cxl_cmd *cmd,
>      CXLType3Class *cvc = CXL_TYPE3_GET_CLASS(ct3d);
>      uint32_t offset, length;
>  
> -    get_lsa = (void *)cmd->payload;
> +    get_lsa = (void *)payload;
>      offset = get_lsa->offset;
>      length = get_lsa->length;
>  
> @@ -439,7 +443,8 @@ static CXLRetCode cmd_ccls_get_lsa(struct cxl_cmd *cmd,
>      return CXL_MBOX_SUCCESS;
>  }
>  
> -static CXLRetCode cmd_ccls_set_lsa(struct cxl_cmd *cmd,
> +static CXLRetCode cmd_ccls_set_lsa(const struct cxl_cmd *cmd,
> +                                   uint8_t *payload,
>                                     CXLDeviceState *cxl_dstate,
>                                     uint16_t *len)
>  {
> @@ -448,7 +453,7 @@ static CXLRetCode cmd_ccls_set_lsa(struct cxl_cmd *cmd,
>          uint32_t rsvd;
>          uint8_t data[];
>      } QEMU_PACKED;
> -    struct set_lsa_pl *set_lsa_payload = (void *)cmd->payload;
> +    struct set_lsa_pl *set_lsa_payload = (void *)payload;
>      CXLType3Dev *ct3d = container_of(cxl_dstate, CXLType3Dev, cxl_dstate);
>      CXLType3Class *cvc = CXL_TYPE3_GET_CLASS(ct3d);
>      const size_t hdr_len = offsetof(struct set_lsa_pl, data);
> @@ -474,7 +479,8 @@ static CXLRetCode cmd_ccls_set_lsa(struct cxl_cmd *cmd,
>   * make this stateful. We may want to allow longer poison lists to aid
>   * testing that kernel functionality.
>   */
> -static CXLRetCode cmd_media_get_poison_list(struct cxl_cmd *cmd,
> +static CXLRetCode cmd_media_get_poison_list(const struct cxl_cmd *cmd,
> +                                            uint8_t *payload,
>                                              CXLDeviceState *cxl_dstate,
>                                              uint16_t *len)
>  {
> @@ -496,8 +502,8 @@ static CXLRetCode cmd_media_get_poison_list(struct cxl_cmd *cmd,
>          } QEMU_PACKED records[];
>      } QEMU_PACKED;
>  
> -    struct get_poison_list_pl *in = (void *)cmd->payload;
> -    struct get_poison_list_out_pl *out = (void *)cmd->payload;
> +    struct get_poison_list_pl *in = (void *)payload;
> +    struct get_poison_list_out_pl *out = (void *)payload;
>      CXLType3Dev *ct3d = container_of(cxl_dstate, CXLType3Dev, cxl_dstate);
>      uint16_t record_count = 0, i = 0;
>      uint64_t query_start, query_length;
> @@ -550,7 +556,8 @@ static CXLRetCode cmd_media_get_poison_list(struct cxl_cmd *cmd,
>      return CXL_MBOX_SUCCESS;
>  }
>  
> -static CXLRetCode cmd_media_inject_poison(struct cxl_cmd *cmd,
> +static CXLRetCode cmd_media_inject_poison(const struct cxl_cmd *cmd,
> +                                          uint8_t *payload,
>                                            CXLDeviceState *cxl_dstate,
>                                            uint16_t *len_unused)
>  {
> @@ -560,7 +567,7 @@ static CXLRetCode cmd_media_inject_poison(struct cxl_cmd *cmd,
>      struct inject_poison_pl {
>          uint64_t dpa;
>      };
> -    struct inject_poison_pl *in = (void *)cmd->payload;
> +    struct inject_poison_pl *in = (void *)payload;
>      uint64_t dpa = ldq_le_p(&in->dpa);
>      CXLPoison *p;
>  
> @@ -589,7 +596,8 @@ static CXLRetCode cmd_media_inject_poison(struct cxl_cmd *cmd,
>      return CXL_MBOX_SUCCESS;
>  }
>  
> -static CXLRetCode cmd_media_clear_poison(struct cxl_cmd *cmd,
> +static CXLRetCode cmd_media_clear_poison(const struct cxl_cmd *cmd,
> +                                         uint8_t *payload,
>                                           CXLDeviceState *cxl_dstate,
>                                           uint16_t *len_unused)
>  {
> @@ -603,7 +611,7 @@ static CXLRetCode cmd_media_clear_poison(struct cxl_cmd *cmd,
>      CXLPoison *ent;
>      uint64_t dpa;
>  
> -    struct clear_poison_pl *in = (void *)cmd->payload;
> +    struct clear_poison_pl *in = (void *)payload;
>  
>      dpa = ldq_le_p(&in->dpa);
>      if (dpa + CXL_CACHE_LINE_SIZE > cxl_dstate->mem_size) {
> @@ -673,7 +681,7 @@ static CXLRetCode cmd_media_clear_poison(struct cxl_cmd *cmd,
>  #define IMMEDIATE_POLICY_CHANGE (1 << 3)
>  #define IMMEDIATE_LOG_CHANGE (1 << 4)
>  
> -static struct cxl_cmd cxl_cmd_set[256][256] = {
> +static const struct cxl_cmd cxl_cmd_set[256][256] = {
>      [EVENTS][GET_RECORDS] = { "EVENTS_GET_RECORDS",
>          cmd_events_get_records, 1, 0 },
>      [EVENTS][CLEAR_RECORDS] = { "EVENTS_CLEAR_RECORDS",
> @@ -709,21 +717,21 @@ static struct cxl_cmd cxl_cmd_set[256][256] = {
>  void cxl_process_mailbox(CXLDeviceState *cxl_dstate)
>  {
>      uint16_t ret = CXL_MBOX_SUCCESS;
> -    struct cxl_cmd *cxl_cmd;
> -    uint64_t status_reg;
> +    const struct cxl_cmd *cxl_cmd;
> +    uint64_t status_reg = 0;
>      opcode_handler h;
>      uint64_t command_reg = cxl_dstate->mbox_reg_state64[R_CXL_DEV_MAILBOX_CMD];
>  
>      uint8_t set = FIELD_EX64(command_reg, CXL_DEV_MAILBOX_CMD, COMMAND_SET);
>      uint8_t cmd = FIELD_EX64(command_reg, CXL_DEV_MAILBOX_CMD, COMMAND);
>      uint16_t len = FIELD_EX64(command_reg, CXL_DEV_MAILBOX_CMD, LENGTH);
> -    cxl_cmd = &cxl_cmd_set[set][cmd];
> +    uint8_t *pl = cxl_dstate->mbox_reg_state + A_CXL_DEV_CMD_PAYLOAD;
> +
> +    cxl_cmd = &cxl_dstate->cxl_cmd_set[set][cmd];
>      h = cxl_cmd->handler;
>      if (h) {
>          if (len == cxl_cmd->in || cxl_cmd->in == ~0) {
> -            cxl_cmd->payload = cxl_dstate->mbox_reg_state +
> -                A_CXL_DEV_CMD_PAYLOAD;
> -            ret = (*h)(cxl_cmd, cxl_dstate, &len);
> +            ret = (*h)(cxl_cmd, pl, cxl_dstate, &len);
>              assert(len <= cxl_dstate->payload_size);
>          } else {
>              ret = CXL_MBOX_INVALID_PAYLOAD_LENGTH;
> @@ -752,10 +760,11 @@ void cxl_process_mailbox(CXLDeviceState *cxl_dstate)
>  
>  void cxl_initialize_mailbox(CXLDeviceState *cxl_dstate)
>  {
> +    cxl_dstate->cxl_cmd_set = cxl_cmd_set;
>      for (int set = 0; set < 256; set++) {
>          for (int cmd = 0; cmd < 256; cmd++) {
> -            if (cxl_cmd_set[set][cmd].handler) {
> -                struct cxl_cmd *c = &cxl_cmd_set[set][cmd];
> +            if (cxl_dstate->cxl_cmd_set[set][cmd].handler) {
> +                const struct cxl_cmd *c = &cxl_dstate->cxl_cmd_set[set][cmd];
>                  struct cel_log *log =
>                      &cxl_dstate->cel_log[cxl_dstate->cel_size];
>  
> -- 
> 2.39.2
>