#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 { , RTE_DMA_PORT_PCIE }

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:

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:

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

◆ RTE_DMADEV_DEFAULT_MAX

#define RTE_DMADEV_DEFAULT_MAX 64

Maximum number of devices if rte_dma_dev_max() is not called.

Examples:: examples/vhost/main.c.

Definition at line 157 of file rte_dmadev.h.

◆ RTE_DMA_FOREACH_DEV

#define RTE_DMA_FOREACH_DEV ( p )

Value:

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.

◆ RTE_DMA_CAPA_MEM_TO_MEM

#define RTE_DMA_CAPA_MEM_TO_MEM RTE_BIT64(0)

Support memory-to-memory transfer

Definition at line 226 of file rte_dmadev.h.

◆ RTE_DMA_CAPA_MEM_TO_DEV

#define RTE_DMA_CAPA_MEM_TO_DEV RTE_BIT64(1)

Support memory-to-device transfer.

Definition at line 228 of file rte_dmadev.h.

◆ RTE_DMA_CAPA_DEV_TO_MEM

#define RTE_DMA_CAPA_DEV_TO_MEM RTE_BIT64(2)

Support device-to-memory transfer.

Definition at line 230 of file rte_dmadev.h.

◆ RTE_DMA_CAPA_DEV_TO_DEV

#define RTE_DMA_CAPA_DEV_TO_DEV RTE_BIT64(3)

Support device-to-device transfer.

Definition at line 232 of file rte_dmadev.h.

◆ RTE_DMA_CAPA_SVA

#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.

◆ RTE_DMA_CAPA_SILENT

#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.

◆ RTE_DMA_CAPA_HANDLES_ERRORS

#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.

◆ RTE_DMA_CAPA_M2D_AUTO_FREE

#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.

◆ RTE_DMA_CAPA_PRI_POLICY_SP

#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.

◆ RTE_DMA_CAPA_OPS_COPY

#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.

◆ RTE_DMA_CAPA_OPS_COPY_SG

#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.

◆ RTE_DMA_CAPA_OPS_FILL

#define RTE_DMA_CAPA_OPS_FILL RTE_BIT64(34)

Support fill operation.

Definition at line 277 of file rte_dmadev.h.

◆ RTE_DMA_ALL_VCHAN

#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.

◆ RTE_DMA_OP_FLAG_FENCE

#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.

◆ RTE_DMA_OP_FLAG_SUBMIT

#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.

◆ RTE_DMA_OP_FLAG_LLC

#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.

◆ RTE_DMA_OP_FLAG_AUTO_FREE

#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

◆ rte_dma_direction

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.

◆ rte_dma_port_type

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.

◆ rte_dma_vchan_status

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.

◆ rte_dma_status_code

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

◆ rte_dma_dev_max()

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.

◆ rte_dma_get_dev_id_by_name()

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.

Examples:: examples/vhost/main.c.

◆ rte_dma_is_valid()

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).

◆ rte_dma_count_avail()

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.

◆ rte_dma_next_dev()

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.

Examples:: examples/dma/dmafwd.c.

◆ rte_dma_info_get()

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.
[out]	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.

Examples:: examples/dma/dmafwd.c, and examples/vhost/main.c.

◆ rte_dma_configure()

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.

Examples:: examples/dma/dmafwd.c, and examples/vhost/main.c.

◆ rte_dma_start()

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.

Examples:: examples/dma/dmafwd.c, and examples/vhost/main.c.

◆ rte_dma_stop()

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.

Examples:: examples/dma/dmafwd.c.

◆ rte_dma_close()

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.

◆ rte_dma_vchan_setup()

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.

Examples:: examples/dma/dmafwd.c, and examples/vhost/main.c.

◆ rte_dma_stats_get()

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.
[out]	stats	The basic statistics structure encapsulated into rte_dma_stats object.

Returns: 0 on success. Otherwise negative value is returned.

Examples:: examples/dma/dmafwd.c.

◆ rte_dma_stats_reset()

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.

◆ rte_dma_vchan_status()

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.
[out]	status	The vchan status

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

◆ rte_dma_dump()

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.

Examples:: examples/dma/dmafwd.c.

◆ rte_dma_copy()

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
	)

inlinestatic

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.

Examples:: examples/dma/dmafwd.c.

Definition at line 863 of file rte_dmadev.h.

◆ rte_dma_copy_sg()

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
	)

inlinestatic

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.

◆ rte_dma_fill()

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
	)

inlinestatic

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.

◆ rte_dma_submit()

static int rte_dma_submit	(	int16_t	dev_id,
		uint16_t	vchan
	)

inlinestatic

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.

Examples:: examples/dma/dmafwd.c.

Definition at line 998 of file rte_dmadev.h.

◆ rte_dma_completed()

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
	)

inlinestatic

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.
[out]	last_idx	The last completed operation's ring_idx. If not required, NULL can be passed in.
[out]	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.

Examples:: examples/dma/dmafwd.c.

Definition at line 1039 of file rte_dmadev.h.

◆ rte_dma_completed_status()

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
	)

inlinestatic

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.
[out]	last_idx	The last completed operation's ring_idx. If not required, NULL can be passed in.
[out]	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.

◆ rte_dma_burst_capacity()

static uint16_t rte_dma_burst_capacity	(	int16_t	dev_id,
		uint16_t	vchan
	)

inlinestatic

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.

Data Structures

Macros

Enumerations

Functions

Detailed Description

Macro Definition Documentation

◆ RTE_DMADEV_DEFAULT_MAX

◆ RTE_DMA_FOREACH_DEV

◆ RTE_DMA_CAPA_MEM_TO_MEM

◆ RTE_DMA_CAPA_MEM_TO_DEV

◆ RTE_DMA_CAPA_DEV_TO_MEM

◆ RTE_DMA_CAPA_DEV_TO_DEV

◆ RTE_DMA_CAPA_SVA

◆ RTE_DMA_CAPA_SILENT

◆ RTE_DMA_CAPA_HANDLES_ERRORS

◆ RTE_DMA_CAPA_M2D_AUTO_FREE

◆ RTE_DMA_CAPA_PRI_POLICY_SP

◆ RTE_DMA_CAPA_OPS_COPY

◆ RTE_DMA_CAPA_OPS_COPY_SG

◆ RTE_DMA_CAPA_OPS_FILL

◆ RTE_DMA_ALL_VCHAN

◆ RTE_DMA_OP_FLAG_FENCE

◆ RTE_DMA_OP_FLAG_SUBMIT

◆ RTE_DMA_OP_FLAG_LLC

◆ RTE_DMA_OP_FLAG_AUTO_FREE

Enumeration Type Documentation

◆ rte_dma_direction

◆ rte_dma_port_type

◆ rte_dma_vchan_status

◆ rte_dma_status_code

Function Documentation

◆ rte_dma_dev_max()

◆ rte_dma_get_dev_id_by_name()

◆ rte_dma_is_valid()

◆ rte_dma_count_avail()

◆ rte_dma_next_dev()

◆ rte_dma_info_get()

◆ rte_dma_configure()

◆ rte_dma_start()

◆ rte_dma_stop()

◆ rte_dma_close()

◆ rte_dma_vchan_setup()

◆ rte_dma_stats_get()

◆ rte_dma_stats_reset()

◆ rte_dma_vchan_status()

◆ rte_dma_dump()

◆ rte_dma_copy()

◆ rte_dma_copy_sg()

◆ rte_dma_fill()

◆ rte_dma_submit()

◆ rte_dma_completed()

◆ rte_dma_completed_status()

◆ rte_dma_burst_capacity()