Provided by: dpdk-doc_25.11-2_all 
NAME
rte_dmadev.h
SYNOPSIS
#include <stdint.h>
#include <errno.h>
#include <rte_bitops.h>
#include <rte_common.h>
#include <rte_uuid.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_inter_domain_param
struct rte_dma_vchan_conf
struct rte_dma_stats
struct rte_dma_sge
struct rte_dma_op
Macros
#define RTE_DMADEV_DEFAULT_MAX 64
#define RTE_DMA_FOREACH_DEV(p)
#define RTE_DMA_CFG_FLAG_SILENT RTE_BIT64(0)
#define RTE_DMA_CFG_FLAG_ENQ_DEQ RTE_BIT64(1)
#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_INTER_PROCESS_DOMAIN RTE_BIT64(9)
#define RTE_DMA_CAPA_INTER_OS_DOMAIN RTE_BIT64(10)
#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)
#define RTE_DMA_CAPA_OPS_ENQ_DEQ RTE_BIT64(35)
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)
Typedefs
typedef void(* rte_dma_access_pair_group_event_cb_t) (int16_t dev_id, int16_t group_id, rte_uuid_t
domain_id, enum rte_dma_access_pair_group_event_type event)
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_inter_domain_type { RTE_DMA_INTER_DOMAIN_NONE, RTE_DMA_INTER_PROCESS_DOMAIN,
RTE_DMA_INTER_OS_DOMAIN }
enum rte_dma_vchan_status { RTE_DMA_VCHAN_IDLE, RTE_DMA_VCHAN_ACTIVE, RTE_DMA_VCHAN_HALTED_ERROR }
enum rte_dma_access_pair_group_event_type { RTE_DMA_GROUP_EVENT_MEMBER_LEFT,
RTE_DMA_GROUP_EVENT_GROUP_DESTROYED }
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)
__rte_experimental int rte_dma_access_pair_group_create (int16_t dev_id, rte_uuid_t domain_id, rte_uuid_t
token, int16_t *group_id, rte_dma_access_pair_group_event_cb_t cb)
__rte_experimental int rte_dma_access_pair_group_destroy (int16_t dev_id, int16_t group_id)
__rte_experimental int rte_dma_access_pair_group_join (int16_t dev_id, rte_uuid_t domain_id, rte_uuid_t
token, int16_t group_id, rte_dma_access_pair_group_event_cb_t cb)
__rte_experimental int rte_dma_access_pair_group_leave (int16_t dev_id, int16_t group_id)
__rte_experimental int rte_dma_access_pair_group_handler_get (int16_t dev_id, int16_t group_id,
rte_uuid_t domain_id, uint16_t *handler)
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)
static uint16_t rte_dma_enqueue_ops (int16_t dev_id, uint16_t vchan, struct rte_dma_op **ops, uint16_t
nb_ops)
static uint16_t rte_dma_dequeue_ops (int16_t dev_id, uint16_t vchan, struct rte_dma_op **ops, uint16_t
nb_ops)
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 159 of file rte_dmadev.h.
#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 218 of file rte_dmadev.h.
#define RTE_DMA_CAPA_MEM_TO_MEM RTE_BIT64(0)
Support memory-to-memory transfer
Definition at line 228 of file rte_dmadev.h.
#define RTE_DMA_CAPA_MEM_TO_DEV RTE_BIT64(1)
Support memory-to-device transfer.
Definition at line 230 of file rte_dmadev.h.
#define RTE_DMA_CAPA_DEV_TO_MEM RTE_BIT64(2)
Support device-to-memory transfer.
Definition at line 232 of file rte_dmadev.h.
#define RTE_DMA_CAPA_DEV_TO_DEV RTE_BIT64(3)
Support device-to-device transfer.
Definition at line 234 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 241 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 247 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 255 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 262 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 269 of file rte_dmadev.h.
#define RTE_DMA_CAPA_INTER_PROCESS_DOMAIN RTE_BIT64(9)
Support inter-process DMA transfers.
When this bit is set, the DMA device can perform memory transfers between different process memory
spaces.
Definition at line 275 of file rte_dmadev.h.
#define RTE_DMA_CAPA_INTER_OS_DOMAIN RTE_BIT64(10)
Support inter-OS domain DMA transfers.
The DMA device can perform memory transfers across different operating system domains.
Definition at line 281 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 287 of file rte_dmadev.h.
#define RTE_DMA_CAPA_OPS_COPY_SG RTE_BIT64(33)
Support scatter-gather list copy operation.
Definition at line 289 of file rte_dmadev.h.
#define RTE_DMA_CAPA_OPS_FILL RTE_BIT64(34)
Support fill operation.
Definition at line 291 of file rte_dmadev.h.
#define RTE_DMA_CAPA_OPS_ENQ_DEQ RTE_BIT64(35)
Support enqueue and dequeue operations.
Definition at line 293 of file rte_dmadev.h.
#define RTE_DMA_CFG_FLAG_SILENT RTE_BIT64(0)
DMA device configuration flags.
See also
struct rte_dma_conf::flags Operate in silent mode
RTE_DMA_CAPA_SILENT
Definition at line 302 of file rte_dmadev.h.
#define RTE_DMA_CFG_FLAG_ENQ_DEQ RTE_BIT64(1)
Enable enqueue and dequeue operations
See also
RTE_DMA_CAPA_OPS_ENQ_DEQ
Definition at line 306 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 733 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 1131 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 1136 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 1141 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 1148 of file rte_dmadev.h.
Typedef Documentation
typedef void(* rte_dma_access_pair_group_event_cb_t) (int16_t dev_id, int16_t group_id, rte_uuid_t domain_id,
enum rte_dma_access_pair_group_event_type event)
This callback is used to notify interested parties (either the group creator or group joiners) about
significant events related to the lifecycle of a DMA access pair group.
Warning
EXPERIMENTAL: this API may change without prior notice.
It can be registered by:
• Group creators or group joiners to be notified when a member leaves the group.
• Group joiners to be notified when the group is destroyed.
Parameters
dev_id Identifier of the DMA device.
group_id Identifier of the access pair group where the event occurred.
domain_id UUID of the domain_id associated with the event. For member leave events, this is the
domain_id of the member that left. For group destruction events, this may refer to the domain_id of
the respective member.
event Type of event that occurred.
See also
rte_dma_access_pair_group_event_type
Definition at line 856 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. When the device supports inter-process or inter-OS
domain transfers, the field type in struct rte_dma_vchan_conf::domain specifies the type of
domain. For memory-to-memory transfers within the same domain or process, type should be set to
RTE_DMA_INTER_DOMAIN_NONE.
See also
struct rte_dma_vchan_conf::direction
struct rte_dma_inter_domain_param::type
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 441 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 487 of file rte_dmadev.h.
enum rte_dma_inter_domain_type
Inter-DMA transfer domain type.
Warning
EXPERIMENTAL: this API may change without prior notice.
This enum defines the types of transfer domains applicable to DMA operations. It helps categorize whether
a DMA transfer is occurring within the same domain, across different processes, or between distinct
operating system domains.
See also
struct rte_dma_inter_domain_param:type
Enumerator
RTE_DMA_INTER_DOMAIN_NONE
No inter-domain transfer; standard DMA within same domain.
RTE_DMA_INTER_PROCESS_DOMAIN
Transfer occurs between different user-space processes.
RTE_DMA_INTER_OS_DOMAIN
Transfer spans across different operating system domains.
Definition at line 607 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 773 of file rte_dmadev.h.
enum rte_dma_access_pair_group_event_type
Event types for DMA access pair group notifications.
Warning
EXPERIMENTAL: this API may change without prior notice.
When the event type is RTE_DMA_GROUP_EVENT_MEMBER_LEFT, the handler associated with the departing
member's domain is no longer valid. Inter-domain DMA operations targeting that domain should be avoided.
When the event type is RTE_DMA_GROUP_EVENT_GROUP_DESTROYED, all handlers associated with the group become
invalid. No further inter-domain DMA operations should be initiated using those handlers.
Enumerator
RTE_DMA_GROUP_EVENT_MEMBER_LEFT
A member left the group (notifies creator and joiners).
RTE_DMA_GROUP_EVENT_GROUP_DESTROYED
Group was destroyed (notifies joiners).
Definition at line 824 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 983 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.
__rte_experimental int rte_dma_access_pair_group_create (int16_t dev_id, rte_uuid_t domain_id, rte_uuid_t
token, int16_t * group_id, rte_dma_access_pair_group_event_cb_t cb)
Create an access pair group to enable secure DMA transfers between devices across different processes or
operating system domains.
Warning
EXPERIMENTAL: this API may change without prior notice.
Parameters
dev_id Identifier of the DMA device initiating the group.
domain_id Unique identifier representing the current process or OS domain.
token Authentication token used to establish the access group.
group_id Pointer to store the ID of the newly created access group.
cb Callback function to be invoked when a member leaves the group.
Returns
0 on success, negative error code on failure.
__rte_experimental int rte_dma_access_pair_group_destroy (int16_t dev_id, int16_t group_id)
Destroy an access pair group if all participating devices have exited.
Warning
EXPERIMENTAL: this API may change without prior notice.
This operation is only permitted by the device that originally created the group; attempts by other
devices will result in failure.
Parameters
dev_id Identifier of the device requesting group destruction.
group_id ID of the access group to be destroyed.
Returns
0 on success, negative value on failure indicating the error code.
__rte_experimental int rte_dma_access_pair_group_join (int16_t dev_id, rte_uuid_t domain_id, rte_uuid_t
token, int16_t group_id, rte_dma_access_pair_group_event_cb_t cb)
Join an existing access group to enable secure DMA transfers between devices across different processes
or OS domains.
Warning
EXPERIMENTAL: this API may change without prior notice.
Parameters
dev_id Identifier of the DMA device attempting to join the group.
domain_id Unique identifier representing the current process or OS domain.
token Authentication token used to validate group membership.
group_id ID of the access group to join.
cb Callback function to be invoked when the device leaves the group or when the group is destroyed
due to some exception or failure.
Returns
0 on success, negative value on failure indicating the error code.
__rte_experimental int rte_dma_access_pair_group_leave (int16_t dev_id, int16_t group_id)
Leave an access group, removing the device's entry from the group table and disabling inter-domain DMA
transfers to and from this device.
Warning
EXPERIMENTAL: this API may change without prior notice.
This operation is not permitted for the device that originally created the group.
Parameters
dev_id Identifier of the device requesting to leave the group.
group_id ID of the access group to leave.
Returns
0 on success, negative value on failure indicating the error code.
__rte_experimental int rte_dma_access_pair_group_handler_get (int16_t dev_id, int16_t group_id, rte_uuid_t
domain_id, uint16_t * handler)
Retrieve the handler associated with a specific domain ID, which is used by the application to query
source or destinationin handler to initiate inter-process or inter-OS DMA transfers.
Warning
EXPERIMENTAL: this API may change without prior notice.
Parameters
dev_id Identifier of the DMA device requesting the handler.
group_id ID of the access group to query.
domain_id Unique identifier of the target process or OS domain.
handler Pointer to store the retrieved handler value.
Returns
0 on success, negative value on failure indicating the error code.
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 1178 of file rte_dmadev.h.
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 1228 of file rte_dmadev.h.
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 1277 of file rte_dmadev.h.
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 1311 of file rte_dmadev.h.
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 1352 of file rte_dmadev.h.
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 1414 of file rte_dmadev.h.
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 1451 of file rte_dmadev.h.
uint16_t rte_dma_enqueue_ops (int16_t dev_id, uint16_t vchan, struct rte_dma_op ** ops, uint16_t nb_ops)
[inline], [static]
Enqueue rte_dma_ops to DMA device, can only be used underlying supports RTE_DMA_CAPA_OPS_ENQ_DEQ and
rte_dma_conf::enable_enq_deq is enabled in rte_dma_configure(). The ops enqueued will be immediately
submitted to the DMA device. The enqueue should be coupled with dequeue to retrieve completed ops, calls
to rte_dma_submit(), rte_dma_completed() and rte_dma_completed_status() are not valid.
Parameters
dev_id The identifier of the device.
vchan The identifier of virtual DMA channel.
ops Pointer to rte_dma_op array.
nb_ops Number of rte_dma_op in the ops array
Returns
uint16_t Number of successfully submitted ops.
Definition at line 1489 of file rte_dmadev.h.
uint16_t rte_dma_dequeue_ops (int16_t dev_id, uint16_t vchan, struct rte_dma_op ** ops, uint16_t nb_ops)
[inline], [static]
Dequeue completed rte_dma_ops submitted to the DMA device, can only be used underlying supports
RTE_DMA_CAPA_OPS_ENQ_DEQ and rte_dma_conf::enable_enq_deq is enabled in rte_dma_configure().
Parameters
dev_id The identifier of the device.
vchan The identifier of virtual DMA channel.
ops Pointer to rte_dma_op array.
nb_ops Size of rte_dma_op array.
Returns
Number of successfully completed ops. Should be less or equal to nb_ops.
Definition at line 1524 of file rte_dmadev.h.
Author
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