Provided by: dpdk-doc_24.11.2-2_all bug

NAME

       rte_dmadev.h

SYNOPSIS

       #include <stdint.h>
       #include <rte_bitops.h>
       #include <rte_common.h>
       #include 'rte_dmadev_core.h'
       #include 'rte_dmadev_trace_fp.h'

   Data Structures
       struct rte_dma_info
       struct rte_dma_conf
       struct rte_dma_port_param
       struct rte_dma_auto_free_param
       struct rte_dma_vchan_conf
       struct rte_dma_stats
       struct rte_dma_sge

   Macros
       #define RTE_DMADEV_DEFAULT_MAX   64
       #define RTE_DMA_FOREACH_DEV(p)
       #define RTE_DMA_ALL_VCHAN   0xFFFFu

       DMA capability

       See also
           struct rte_dma_info::dev_capa

           #define RTE_DMA_CAPA_MEM_TO_MEM   RTE_BIT64(0)
           #define RTE_DMA_CAPA_MEM_TO_DEV   RTE_BIT64(1)
           #define RTE_DMA_CAPA_DEV_TO_MEM   RTE_BIT64(2)
           #define RTE_DMA_CAPA_DEV_TO_DEV   RTE_BIT64(3)
           #define RTE_DMA_CAPA_SVA   RTE_BIT64(4)
           #define RTE_DMA_CAPA_SILENT   RTE_BIT64(5)
           #define RTE_DMA_CAPA_HANDLES_ERRORS   RTE_BIT64(6)
           #define RTE_DMA_CAPA_M2D_AUTO_FREE   RTE_BIT64(7)
           #define RTE_DMA_CAPA_PRI_POLICY_SP   RTE_BIT64(8)
           #define RTE_DMA_CAPA_OPS_COPY   RTE_BIT64(32)
           #define RTE_DMA_CAPA_OPS_COPY_SG   RTE_BIT64(33)
           #define RTE_DMA_CAPA_OPS_FILL   RTE_BIT64(34)

       DMA operation flag

       See also
           rte_dma_copy()

           rte_dma_copy_sg()

           rte_dma_fill()

           #define RTE_DMA_OP_FLAG_FENCE   RTE_BIT64(0)
           #define RTE_DMA_OP_FLAG_SUBMIT   RTE_BIT64(1)
           #define RTE_DMA_OP_FLAG_LLC   RTE_BIT64(2)
           #define RTE_DMA_OP_FLAG_AUTO_FREE   RTE_BIT64(3)

   Enumerations
       enum rte_dma_direction { RTE_DMA_DIR_MEM_TO_MEM, RTE_DMA_DIR_MEM_TO_DEV, RTE_DMA_DIR_DEV_TO_MEM,
           RTE_DMA_DIR_DEV_TO_DEV }
       enum rte_dma_port_type {  }
       enum rte_dma_vchan_status { RTE_DMA_VCHAN_IDLE, RTE_DMA_VCHAN_ACTIVE, RTE_DMA_VCHAN_HALTED_ERROR }
       enum rte_dma_status_code { RTE_DMA_STATUS_SUCCESSFUL, RTE_DMA_STATUS_USER_ABORT,
           RTE_DMA_STATUS_NOT_ATTEMPTED, RTE_DMA_STATUS_INVALID_SRC_ADDR, RTE_DMA_STATUS_INVALID_DST_ADDR,
           RTE_DMA_STATUS_INVALID_ADDR, RTE_DMA_STATUS_INVALID_LENGTH, RTE_DMA_STATUS_INVALID_OPCODE,
           RTE_DMA_STATUS_BUS_READ_ERROR, RTE_DMA_STATUS_BUS_WRITE_ERROR, RTE_DMA_STATUS_BUS_ERROR,
           RTE_DMA_STATUS_DATA_POISION, RTE_DMA_STATUS_DESCRIPTOR_READ_ERROR, RTE_DMA_STATUS_DEV_LINK_ERROR,
           RTE_DMA_STATUS_PAGE_FAULT, RTE_DMA_STATUS_ERROR_UNKNOWN = 0x100 }

   Functions
       int rte_dma_dev_max (size_t dev_max)
       int rte_dma_get_dev_id_by_name (const char *name)
       bool rte_dma_is_valid (int16_t dev_id)
       uint16_t rte_dma_count_avail (void)
       int16_t rte_dma_next_dev (int16_t start_dev_id)
       int rte_dma_info_get (int16_t dev_id, struct rte_dma_info *dev_info)
       int rte_dma_configure (int16_t dev_id, const struct rte_dma_conf *dev_conf)
       int rte_dma_start (int16_t dev_id)
       int rte_dma_stop (int16_t dev_id)
       int rte_dma_close (int16_t dev_id)
       int rte_dma_vchan_setup (int16_t dev_id, uint16_t vchan, const struct rte_dma_vchan_conf *conf)
       int rte_dma_stats_get (int16_t dev_id, uint16_t vchan, struct rte_dma_stats *stats)
       int rte_dma_stats_reset (int16_t dev_id, uint16_t vchan)
       int rte_dma_vchan_status (int16_t dev_id, uint16_t vchan, enum rte_dma_vchan_status *status)
       int rte_dma_dump (int16_t dev_id, FILE *f)
       static int rte_dma_copy (int16_t dev_id, uint16_t vchan, rte_iova_t src, rte_iova_t dst, uint32_t length,
           uint64_t flags)
       static int rte_dma_copy_sg (int16_t dev_id, uint16_t vchan, struct rte_dma_sge *src, struct rte_dma_sge
           *dst, uint16_t nb_src, uint16_t nb_dst, uint64_t flags)
       static int rte_dma_fill (int16_t dev_id, uint16_t vchan, uint64_t pattern, rte_iova_t dst, uint32_t
           length, uint64_t flags)
       static int rte_dma_submit (int16_t dev_id, uint16_t vchan)
       static uint16_t rte_dma_completed (int16_t dev_id, uint16_t vchan, const uint16_t nb_cpls, uint16_t
           *last_idx, bool *has_error)
       static uint16_t rte_dma_completed_status (int16_t dev_id, uint16_t vchan, const uint16_t nb_cpls,
           uint16_t *last_idx, enum rte_dma_status_code *status)
       static uint16_t rte_dma_burst_capacity (int16_t dev_id, uint16_t vchan)

Detailed Description

       DMA (Direct Memory Access) device API.

       The DMA framework is built on the following model:

       ---------------   ---------------       ---------------
       | virtual DMA |   | virtual DMA |       | virtual DMA |
       | channel     |   | channel     |       | channel     |
       ---------------   ---------------       ---------------
              |                |                      |
              ------------------                      |
                       |                              |
                 ------------                    ------------
                 |  dmadev  |                    |  dmadev  |
                 ------------                    ------------
                       |                              |
              ------------------               ------------------
              | HW DMA channel |               | HW DMA channel |
              ------------------               ------------------
                       |                              |
                       --------------------------------
                                       |
                             ---------------------
                             | HW DMA Controller |
                             ---------------------

        The DMA controller could have multiple HW-DMA-channels (aka. HW-DMA-queues), each HW-DMA-channel should
       be represented by a dmadev.

       The dmadev could create multiple virtual DMA channels, each virtual DMA channel represents a different
       transfer context. The DMA operation request must be submitted to the virtual DMA channel. e.g.
       Application could create virtual DMA channel 0 for memory-to-memory transfer scenario, and create virtual
       DMA channel 1 for memory-to-device transfer scenario.

       This framework uses 'int16_t dev_id' as the device identifier of a dmadev, and 'uint16_t vchan' as the
       virtual DMA channel identifier in one dmadev.

       The functions exported by the dmadev API to setup a device designated by its device identifier must be
       invoked in the following order:

       • rte_dma_configure()rte_dma_vchan_setup()rte_dma_start()

       Then, the application can invoke dataplane functions to process jobs.

       If   the   application   wants   to   change   the  configuration  (i.e.  invoke  rte_dma_configure()  or
       rte_dma_vchan_setup()), it must  invoke  rte_dma_stop()  first  to  stop  the  device  and  then  do  the
       reconfiguration before invoking rte_dma_start() again. The dataplane functions should not be invoked when
       the device is stopped.

       Finally, an application can close a dmadev by invoking the rte_dma_close() function.

       The dataplane APIs include two parts: The first part is the submission of operation requests:

       • rte_dma_copy()rte_dma_copy_sg()rte_dma_fill()rte_dma_submit()

       These APIs could work with different virtual DMA channels which have different contexts.

       The  first  three  APIs  are  used  to  submit  the  operation request to the virtual DMA channel, if the
       submission is successful, a positive ring_idx <= UINT16_MAX is returned, otherwise a negative  number  is
       returned.

       The last API is used to issue doorbell to hardware, and also there are flags (

       See also
           RTE_DMA_OP_FLAG_SUBMIT) parameter of the first three APIs could do the same work.

       Note
           When enqueuing a set of jobs to the device, having a separate submit outside a loop makes for clearer
           code  than  having  a  check  for  the  last  iteration inside the loop to set a special submit flag.
           However, for cases where one item alone is to be submitted or there is a small  set  of  jobs  to  be
           submitted  sequentially,  having  a submit flag provides a lower-overhead way of doing the submission
           while still keeping the code clean.

       The second part is to obtain the result of requests:

       • rte_dma_completed()

         • return the number of operation requests completed successfully.

       • rte_dma_completed_status()

         • return the number of operation requests completed.

       Note
           If the dmadev works in silent mode (

       See also
           RTE_DMA_CAPA_SILENT), application does not invoke the above two completed APIs.

       About the ring_idx which enqueue APIs (e.g. rte_dma_copy(), rte_dma_fill())  return,  the  rules  are  as
       follows:

       • ring_idx for each virtual DMA channel are independent.

       • For  a  virtual  DMA  channel,  the ring_idx is monotonically incremented, when it reach UINT16_MAX, it
         wraps back to zero.

       • This ring_idx can be used by applications to track per-operation  metadata  in  an  application-defined
         circular ring.

       • The  initial ring_idx of a virtual DMA channel is zero, after the device is stopped, the ring_idx needs
         to be reset to zero.

       One example:

       • step-1: start one dmadev

       • step-2: enqueue a copy operation, the ring_idx return is 0

       • step-3: enqueue a copy operation again, the ring_idx return is 1

       • ...

       • step-101: stop the dmadev

       • step-102: start the dmadev

       • step-103: enqueue a copy operation, the ring_idx return is 0

       • ...

       • step-x+0: enqueue a fill operation, the ring_idx return is 65535

       • step-x+1: enqueue a copy operation, the ring_idx return is 0

       • ...

       The DMA operation address used in enqueue APIs (i.e. rte_dma_copy(),  rte_dma_copy_sg(),  rte_dma_fill())
       is defined as rte_iova_t type.

       The dmadev supports two types of address: memory address and device address.

       • memory address: the source and destination address of the memory-to-memory transfer type, or the source
         address  of  the  memory-to-device  transfer  type,  or the destination address of the device-to-memory
         transfer type.

       Note
           If the device support SVA (

       See also
           RTE_DMA_CAPA_SVA), the memory address can be any VA address, otherwise it must be an IOVA address.

       • device address: the source and destination address of the device-to-device transfer type, or the source
         address of the device-to-memory transfer type, or  the  destination  address  of  the  memory-to-device
         transfer type.

       About  MT-safe,  all  the  functions of the dmadev API implemented by a PMD are lock-free functions which
       assume to not be invoked in parallel on different logical cores to work on the same target dmadev object.

       Note
           Different virtual DMA channels on the same dmadev DO NOT support parallel  invocation  because  these
           virtual DMA channels share the same HW-DMA-channel.

       Definition in file rte_dmadev.h.

Macro Definition Documentation

   #define RTE_DMADEV_DEFAULT_MAX   64
       Maximum number of devices if rte_dma_dev_max() is not called.

       Definition at line 157 of file rte_dmadev.h.

   #define RTE_DMA_FOREACH_DEV(p)
       Value:.PP
           for (p = rte_dma_next_dev(0); \
                p != -1; \
                p = rte_dma_next_dev(p + 1))
       Utility macro to iterate over all available dmadevs

       Definition at line 216 of file rte_dmadev.h.

   #define RTE_DMA_CAPA_MEM_TO_MEM   RTE_BIT64(0)
       Support memory-to-memory transfer

       Definition at line 226 of file rte_dmadev.h.

   #define RTE_DMA_CAPA_MEM_TO_DEV   RTE_BIT64(1)
       Support memory-to-device transfer.

       Definition at line 228 of file rte_dmadev.h.

   #define RTE_DMA_CAPA_DEV_TO_MEM   RTE_BIT64(2)
       Support device-to-memory transfer.

       Definition at line 230 of file rte_dmadev.h.

   #define RTE_DMA_CAPA_DEV_TO_DEV   RTE_BIT64(3)
       Support device-to-device transfer.

       Definition at line 232 of file rte_dmadev.h.

   #define RTE_DMA_CAPA_SVA   RTE_BIT64(4)
       Support  SVA  which could use VA as DMA address. If device support SVA then application could pass any VA
       address like memory from rte_malloc(), rte_memzone(), malloc, stack memory. If device don't support  SVA,
       then application should pass IOVA address which from rte_malloc(), rte_memzone().

       Definition at line 239 of file rte_dmadev.h.

   #define RTE_DMA_CAPA_SILENT   RTE_BIT64(5)
       Support work in silent mode. In this mode, application don't required to invoke rte_dma_completed*() API.

       See also
           struct rte_dma_conf::silent_mode

       Definition at line 245 of file rte_dmadev.h.

   #define RTE_DMA_CAPA_HANDLES_ERRORS   RTE_BIT64(6)
       Supports error handling

       With  this  bit set, invalid input addresses will be reported as operation failures to the user but other
       operations can continue. Without this bit set, invalid data is not handled by either  HW  or  driver,  so
       user must ensure that all memory addresses are valid and accessible by HW.

       Definition at line 253 of file rte_dmadev.h.

   #define RTE_DMA_CAPA_M2D_AUTO_FREE   RTE_BIT64(7)
       Support auto free for source buffer once mem to dev transfer is completed.

       Note
           Even  though  the  DMA  driver  has  this  capability, it may not support all mempool drivers. If the
           mempool is not supported by the DMA driver, rte_dma_vchan_setup() will fail.

       Definition at line 260 of file rte_dmadev.h.

   #define RTE_DMA_CAPA_PRI_POLICY_SP   RTE_BIT64(8)
       Support strict priority scheduling.

       Application could assign fixed priority to the DMA device using 'priority' field in struct  rte_dma_conf.
       Number of supported priority levels will be known from 'nb_priorities' field in struct rte_dma_info.

       Definition at line 267 of file rte_dmadev.h.

   #define RTE_DMA_CAPA_OPS_COPY   RTE_BIT64(32)
       Support copy operation. This capability start with index of 32, so that it could leave gap between normal
       capability and ops capability.

       Definition at line 273 of file rte_dmadev.h.

   #define RTE_DMA_CAPA_OPS_COPY_SG   RTE_BIT64(33)
       Support scatter-gather list copy operation.

       Definition at line 275 of file rte_dmadev.h.

   #define RTE_DMA_CAPA_OPS_FILL   RTE_BIT64(34)
       Support fill operation.

       Definition at line 277 of file rte_dmadev.h.

   #define RTE_DMA_ALL_VCHAN   0xFFFFu
       Special ID, which is used to represent all virtual DMA channels.

       See also
           rte_dma_stats_get

           rte_dma_stats_reset

       Definition at line 643 of file rte_dmadev.h.

   #define RTE_DMA_OP_FLAG_FENCE   RTE_BIT64(0)
       Fence  flag.  It  means the operation with this flag must be processed only after all previous operations
       are completed. If the specify DMA HW works in-order (it means it has default fence  between  operations),
       this flag could be NOP.

       Definition at line 816 of file rte_dmadev.h.

   #define RTE_DMA_OP_FLAG_SUBMIT   RTE_BIT64(1)
       Submit flag. It means the operation with this flag must issue doorbell to hardware after enqueued jobs.

       Definition at line 821 of file rte_dmadev.h.

   #define RTE_DMA_OP_FLAG_LLC   RTE_BIT64(2)
       Write  data to low level cache hint. Used for performance optimization, this is just a hint, and there is
       no capability bit for this, driver should not return error if this flag was set.

       Definition at line 826 of file rte_dmadev.h.

   #define RTE_DMA_OP_FLAG_AUTO_FREE   RTE_BIT64(3)
       Auto free buffer flag. Operation with this flag must issue command to hardware to  free  the  DMA  buffer
       after DMA transfer is completed.

       See also
           struct rte_dma_vchan_conf::auto_free

       Definition at line 833 of file rte_dmadev.h.

Enumeration Type Documentation

   enum rte_dma_direction
       DMA transfer direction defines.

       See also
           struct rte_dma_vchan_conf::direction

       Enumerator

       RTE_DMA_DIR_MEM_TO_MEM
              DMA transfer direction - from memory to memory.

       See also
           struct rte_dma_vchan_conf::direction

       RTE_DMA_DIR_MEM_TO_DEV
              DMA  transfer  direction - from memory to device. In a typical scenario, the SoCs are installed on
              host servers as iNICs through the PCIe interface. In this case, the  SoCs  works  in  EP(endpoint)
              mode,  it could initiate a DMA move request from memory (which is SoCs memory) to device (which is
              host memory).

       See also
           struct rte_dma_vchan_conf::direction

       RTE_DMA_DIR_DEV_TO_MEM
              DMA transfer direction - from device to memory. In a typical scenario, the SoCs are  installed  on
              host  servers  as  iNICs  through the PCIe interface. In this case, the SoCs works in EP(endpoint)
              mode, it could initiate a DMA move request from device (which is host memory) to memory (which  is
              SoCs memory).

       See also
           struct rte_dma_vchan_conf::direction

       RTE_DMA_DIR_DEV_TO_DEV
              DMA  transfer  direction - from device to device. In a typical scenario, the SoCs are installed on
              host servers as iNICs through the PCIe interface. In this case, the  SoCs  works  in  EP(endpoint)
              mode, it could initiate a DMA move request from device (which is host memory) to the device (which
              is another host memory).

       See also
           struct rte_dma_vchan_conf::direction

       Definition at line 419 of file rte_dmadev.h.

   enum rte_dma_port_type
       DMA access port type defines.

       See also
           struct rte_dma_port_param::port_type

       Enumerator

       RTE_DMA_PORT_PCIE
              The DMA access port is PCIe.

       Definition at line 459 of file rte_dmadev.h.

   enum rte_dma_vchan_status
       device vchannel status

       Enum with the options for the channel status, either idle, active or halted due to error

       See also
           rte_dma_vchan_status

       Enumerator

       RTE_DMA_VCHAN_IDLE
              not processing, awaiting ops

       RTE_DMA_VCHAN_ACTIVE
              currently processing jobs

       RTE_DMA_VCHAN_HALTED_ERROR
              not processing due to error, cannot accept new ops

       Definition at line 683 of file rte_dmadev.h.

   enum rte_dma_status_code
       DMA transfer result status code defines.

       See also
           rte_dma_completed_status

       Enumerator

       RTE_DMA_STATUS_SUCCESSFUL
              The operation completed successfully.

       RTE_DMA_STATUS_USER_ABORT
              The  operation failed to complete due abort by user. This is mainly used when processing dev_stop,
              user could modify the descriptors (e.g. change one bit to tell hardware abort this job), it allows
              outstanding requests to be complete as much as possible, so reduce the time to stop the device.

       RTE_DMA_STATUS_NOT_ATTEMPTED
              The operation failed to complete due to following scenarios: The jobs in a  particular  batch  are
              not  attempted  because  they  appeared  after  a  fence  where  a previous job failed. In some HW
              implementation it's possible for jobs from later batches would be completed, though, so report the
              status from the not attempted jobs before reporting those newer completed jobs.

       RTE_DMA_STATUS_INVALID_SRC_ADDR
              The operation failed to complete due invalid source address.

       RTE_DMA_STATUS_INVALID_DST_ADDR
              The operation failed to complete due invalid destination address.

       RTE_DMA_STATUS_INVALID_ADDR
              The operation failed to complete due invalid source or destination address, cover  the  case  that
              only knows the address error, but not sure which address error.

       RTE_DMA_STATUS_INVALID_LENGTH
              The operation failed to complete due invalid length.

       RTE_DMA_STATUS_INVALID_OPCODE
              The  operation  failed  to  complete  due  invalid  opcode. The DMA descriptor could have multiple
              format, which are distinguished by the opcode field.

       RTE_DMA_STATUS_BUS_READ_ERROR
              The operation failed to complete due bus read error.

       RTE_DMA_STATUS_BUS_WRITE_ERROR
              The operation failed to complete due bus write error.

       RTE_DMA_STATUS_BUS_ERROR
              The operation failed to complete due bus error, cover the case that only knows the bus error,  but
              not sure which direction error.

       RTE_DMA_STATUS_DATA_POISION
              The operation failed to complete due data poison.

       RTE_DMA_STATUS_DESCRIPTOR_READ_ERROR
              The operation failed to complete due descriptor read error.

       RTE_DMA_STATUS_DEV_LINK_ERROR
              The  operation  failed to complete due device link error. Used to indicates that the link error in
              the memory-to-device/ device-to-memory/device-to-device transfer scenario.

       RTE_DMA_STATUS_PAGE_FAULT
              The operation failed to complete due lookup page fault.

       RTE_DMA_STATUS_ERROR_UNKNOWN
              The operation failed to complete due unknown reason. The initial  value  is  256,  which  reserves
              space for future errors.

       Definition at line 725 of file rte_dmadev.h.

Function Documentation

   int rte_dma_dev_max (size_t dev_max)
       Configure the maximum number of dmadevs.

       Note
           This  function  can be invoked before the primary process rte_eal_init() to change the maximum number
           of dmadevs. If not invoked, the maximum number of dmadevs is

       See also
           RTE_DMADEV_DEFAULT_MAX

       Parameters
           dev_max maximum number of dmadevs.

       Returns
           0 on success. Otherwise negative value is returned.

   int rte_dma_get_dev_id_by_name (const char * name)
       Get the device identifier for the named DMA device.

       Parameters
           name DMA device name.

       Returns
           Returns DMA device identifier on success.

           • <0: Failure to find named DMA device.

   bool rte_dma_is_valid (int16_t dev_id)
       Check whether the dev_id is valid.

       Parameters
           dev_id DMA device index.

       Returns

           • If the device index is valid (true) or not (false).

   uint16_t rte_dma_count_avail (void)
       Get the total number of DMA devices that have been successfully initialised.

       Returns
           The total number of usable DMA devices.

   int16_t rte_dma_next_dev (int16_t start_dev_id)
       Iterates over valid dmadev instances.

       Parameters
           start_dev_id The id of the next possible dmadev.

       Returns
           Next valid dmadev, UINT16_MAX if there is none.

   int rte_dma_info_get (int16_t dev_id, struct rte_dma_info * dev_info)
       Retrieve information of a DMA device.

       Parameters
           dev_id The identifier of the device.
           dev_info A pointer to a structure of type rte_dma_info to be  filled  with  the  information  of  the
           device.

       Returns
           0 on success. Otherwise negative value is returned.

   int rte_dma_configure (int16_t dev_id, const struct rte_dma_conf * dev_conf)
       Configure a DMA device.

       This  function  must be invoked first before any other function in the API. This function can also be re-
       invoked when a device is in the stopped state.

       Parameters
           dev_id The identifier of the device to configure.
           dev_conf The DMA device configuration structure encapsulated into rte_dma_conf object.

       Returns
           0 on success. Otherwise negative value is returned.

   int rte_dma_start (int16_t dev_id)
       Start a DMA device.

       The device start step is the last one and consists of setting the DMA to start accepting jobs.

       Parameters
           dev_id The identifier of the device.

       Returns
           0 on success. Otherwise negative value is returned.

   int rte_dma_stop (int16_t dev_id)
       Stop a DMA device.

       The device can be restarted with a call to rte_dma_start().

       Parameters
           dev_id The identifier of the device.

       Returns
           0 on success. Otherwise negative value is returned.

   int rte_dma_close (int16_t dev_id)
       Close a DMA device.

       The device cannot be restarted after this call.

       Parameters
           dev_id The identifier of the device.

       Returns
           0 on success. Otherwise negative value is returned.

   int rte_dma_vchan_setup (int16_t dev_id, uint16_t vchan, const struct rte_dma_vchan_conf * conf)
       Allocate and set up a virtual DMA channel.

       Parameters
           dev_id The identifier of the device.
           vchan The identifier of virtual DMA channel. The value must be  in  the  range  [0,  nb_vchans  -  1]
           previously supplied to rte_dma_configure().
           conf The virtual DMA channel configuration structure encapsulated into rte_dma_vchan_conf object.

       Returns
           0 on success. Otherwise negative value is returned.

   int rte_dma_stats_get (int16_t dev_id, uint16_t vchan, struct rte_dma_stats * stats)
       Retrieve basic statistics of a or all virtual DMA channel(s).

       Parameters
           dev_id The identifier of the device.
           vchan The identifier of virtual DMA channel. If equal RTE_DMA_ALL_VCHAN means all channels.
           stats The basic statistics structure encapsulated into rte_dma_stats object.

       Returns
           0 on success. Otherwise negative value is returned.

   int rte_dma_stats_reset (int16_t dev_id, uint16_t vchan)
       Reset basic statistics of a or all virtual DMA channel(s).

       Parameters
           dev_id The identifier of the device.
           vchan The identifier of virtual DMA channel. If equal RTE_DMA_ALL_VCHAN means all channels.

       Returns
           0 on success. Otherwise negative value is returned.

   int rte_dma_vchan_status (int16_t dev_id, uint16_t vchan, enum rte_dma_vchan_status * status)
       Determine if all jobs have completed on a device channel. This function is primarily designed for testing
       use,  as  it  allows a process to check if all jobs are completed, without actually gathering completions
       from those jobs.

       Parameters
           dev_id The identifier of the device.
           vchan The identifier of virtual DMA channel.
           status The vchan status

       Returns
           0 - call completed successfully < 0 - error code indicating there was a problem calling the API

   int rte_dma_dump (int16_t dev_id, FILE * f)
       Dump DMA device info.

       Parameters
           dev_id The identifier of the device.
           f The file to write the output to.

       Returns
           0 on success. Otherwise negative value is returned.

   static int rte_dma_copy (int16_t dev_id, uint16_t vchan, rte_iova_t src,  rte_iova_t  dst,  uint32_t  length,
       uint64_t flags) [inline],  [static]
       Enqueue a copy operation onto the virtual DMA channel.

       This  queues  up  a  copy  operation  to  be  performed  by  hardware,  if the 'flags' parameter contains
       RTE_DMA_OP_FLAG_SUBMIT then trigger doorbell to begin this operation, otherwise do not trigger doorbell.

       Parameters
           dev_id The identifier of the device.
           vchan The identifier of virtual DMA channel.
           src The address of the source buffer.
           dst The address of the destination buffer.
           length The length of the data to be copied.
           flags An flags for this operation.

       See also
           RTE_DMA_OP_FLAG_*

       Returns

           • 0..UINT16_MAX: index of enqueued job.

           • -ENOSPC: if no space left to enqueue.

           • other values < 0 on failure.

       Definition at line 863 of file rte_dmadev.h.

   static int rte_dma_copy_sg (int16_t dev_id, uint16_t vchan, struct rte_dma_sge * src,  struct  rte_dma_sge  *
       dst, uint16_t nb_src, uint16_t nb_dst, uint64_t flags) [inline],  [static]
       Enqueue a scatter-gather list copy operation onto the virtual DMA channel.

       This queues up a scatter-gather list copy operation to be performed by hardware, if the 'flags' parameter
       contains  RTE_DMA_OP_FLAG_SUBMIT  then trigger doorbell to begin this operation, otherwise do not trigger
       doorbell.

       Parameters
           dev_id The identifier of the device.
           vchan The identifier of virtual DMA channel.
           src The pointer of source scatter-gather entry array.
           dst The pointer of destination scatter-gather entry array.
           nb_src The number of source scatter-gather entry.

       See also
           struct rte_dma_info::max_sges

       Parameters
           nb_dst The number of destination scatter-gather entry.

       See also
           struct rte_dma_info::max_sges

       Parameters
           flags An flags for this operation.

       See also
           RTE_DMA_OP_FLAG_*

       Returns

           • 0..UINT16_MAX: index of enqueued job.

           • -ENOSPC: if no space left to enqueue.

           • other values < 0 on failure.

       Definition at line 913 of file rte_dmadev.h.

   static int rte_dma_fill (int16_t dev_id, uint16_t vchan, uint64_t pattern, rte_iova_t dst,  uint32_t  length,
       uint64_t flags) [inline],  [static]
       Enqueue a fill operation onto the virtual DMA channel.

       This  queues  up  a  fill  operation  to  be  performed  by  hardware,  if the 'flags' parameter contains
       RTE_DMA_OP_FLAG_SUBMIT then trigger doorbell to begin this operation, otherwise do not trigger doorbell.

       Parameters
           dev_id The identifier of the device.
           vchan The identifier of virtual DMA channel.
           pattern The pattern to populate the destination buffer with.
           dst The address of the destination buffer.
           length The length of the destination buffer.
           flags An flags for this operation.

       See also
           RTE_DMA_OP_FLAG_*

       Returns

           • 0..UINT16_MAX: index of enqueued job.

           • -ENOSPC: if no space left to enqueue.

           • other values < 0 on failure.

       Definition at line 963 of file rte_dmadev.h.

   static int rte_dma_submit (int16_t dev_id, uint16_t vchan) [inline],  [static]
       Trigger hardware to begin performing enqueued operations.

       Writes the 'doorbell' to the hardware to trigger it  to  begin  the  operations  previously  enqueued  by
       rte_dma_copy/fill().

       Parameters
           dev_id The identifier of the device.
           vchan The identifier of virtual DMA channel.

       Returns
           0 on success. Otherwise negative value is returned.

       Definition at line 998 of file rte_dmadev.h.

   static  uint16_t  rte_dma_completed  (int16_t  dev_id,  uint16_t  vchan,  const  uint16_t nb_cpls, uint16_t *
       last_idx, bool * has_error) [inline],  [static]
       Return the number of operations that have  been  successfully  completed.  Once  an  operation  has  been
       reported as completed, the results of that operation will be visible to all cores on the system.

       Parameters
           dev_id The identifier of the device.
           vchan The identifier of virtual DMA channel.
           nb_cpls The maximum number of completed operations that can be processed.
           last_idx The last completed operation's ring_idx. If not required, NULL can be passed in.
           has_error Indicates if there are transfer error. If not required, NULL can be passed in.

       Returns
           The number of operations that successfully completed. This return value must be less than or equal to
           the value of nb_cpls.

       Definition at line 1039 of file rte_dmadev.h.

   static  uint16_t rte_dma_completed_status (int16_t dev_id, uint16_t vchan, const uint16_t nb_cpls, uint16_t *
       last_idx, enum rte_dma_status_code * status) [inline],  [static]
       Return the number of operations that have been completed, and the operations result may succeed or  fail.
       Once  an  operation  has  been  reported as completed successfully, the results of that operation will be
       visible to all cores on the system.

       Parameters
           dev_id The identifier of the device.
           vchan The identifier of virtual DMA channel.
           nb_cpls Indicates the size of status array.
           last_idx The last completed operation's ring_idx. If not required, NULL can be passed in.
           status This is a pointer to an array of length 'nb_cpls' that holds the  completion  status  code  of
           each operation.

       See also
           enum rte_dma_status_code

       Returns
           The number of operations that completed. This return value must be less than or equal to the value of
           nb_cpls. If this number is greater than zero (assuming n), then n values in the status array are also
           set.

       Definition at line 1102 of file rte_dmadev.h.

   static uint16_t rte_dma_burst_capacity (int16_t dev_id, uint16_t vchan) [inline],  [static]
       Check remaining capacity in descriptor ring for the current burst.

       Parameters
           dev_id The identifier of the device.
           vchan The identifier of virtual DMA channel.

       Returns

           • Remaining space in the descriptor ring for the current burst.

           • 0 on error

       Definition at line 1140 of file rte_dmadev.h.

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DPDK                                             Version 24.11.2                                 rte_dmadev.h(3)