A minor comment below, but it seems could fix later. Acked-by: Chengwen Feng On 2025/10/17 20:26, Vamsi Krishna wrote: > From: Vamsi Attunuru > > Secure and controlled inter-domain DMA transfers require dedicated > control-plane APIs to create and manage access groups. > > DMA devices used for inter-process data transfer can be categorized as > follows: > > Class A: Both endpoints require a DMA device for data transfer (e.g., > Marvell DMA devices). > Class B: Only one endpoint requires a DMA device; the other does not. > Class C: Other device types not currently classified. > > Providing a unified API for all these categories is complex, as Linux > and other operating systems do not offer native control-plane APIs for > this purpose. Therefore, DPDK can implement its own control-plane > mechanisms to support Class A, B, and C devices. > > This commit introduces the necessary APIs for Class A DMA devices. > Devices can create or join access groups using token-based > authentication, ensuring that only authorized devices within the same > group can perform DMA transfers across processes or OS domains. > > API Usage Flow: > > Process 1 (Group Creator): > Invokes rte_dma_access_pair_group_create() to establish a new access > pair group, then shares the group_id and token with Process 2 via IPC. > > Process 2 (Group Joiner): > Receives the group_id and token from Process 1 and calls > rte_dma_access_pair_group_join() to join the group. > > Both Processes: > Use rte_dma_access_pair_group_handler_get() to obtain handler information > for domains in the group. > Perform DMA transfers as required. > > Process 2 (when finished): > Calls rte_dma_access_pair_group_leave() to exit the group. > > Process 1: > Monitors for group updates and confirms group membership as needed. > > Depends-on: patch-36335 (lib/dma: introduce inter-process and inter-OS DMA) > > Signed-off-by: Vamsi Attunuru > --- > V3 Changes: > * Add documentation to dmadev doc. > * Add common callback for group creator and joiner. > * Fix V2 review comments > > doc/guides/prog_guide/dmadev.rst | 49 +++++++++++ > lib/dmadev/rte_dmadev.c | 138 +++++++++++++++++++++++++++++++ > lib/dmadev/rte_dmadev.h | 137 ++++++++++++++++++++++++++++++ > lib/dmadev/rte_dmadev_pmd.h | 29 +++++++ > lib/dmadev/rte_dmadev_trace.h | 42 ++++++++++ > 5 files changed, 395 insertions(+) > > diff --git a/doc/guides/prog_guide/dmadev.rst b/doc/guides/prog_guide/dmadev.rst > index 9b497ce7bd..c2a1e34c35 100644 > --- a/doc/guides/prog_guide/dmadev.rst > +++ b/doc/guides/prog_guide/dmadev.rst > @@ -174,3 +174,52 @@ are shown below. > > For more information on how to use the Telemetry interface, see > the :doc:`../howto/telemetry`. > + > +Inter-domain DMA Capabilities > +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > + > +The inter-domain DMA feature enables DMA devices to perform data transfers > +across different processes and OS domains. This is achieved by configuring > +virtual channels (vchans) using `src_handler` and `dst_handler` fields, which > +represent the source and destination endpoints for inter-domain DMA operations. > +Handler information is exchanged between devices based on their DMA class type. > +These handler details will be exchanged based on the type of DMA devices. > + > +DMA devices used for inter-process data transfer can be categorized as follows: inter-process -> inter-domain > + > +Class A: Both endpoints require a DMA device for data transfer (e.g., Marvell DMA devices). > +Class B: Only one endpoint requires a DMA device; the other does not. > +Class C: Other device types not currently classified. > + > +Currently the necessary APIs for Class A DMA devices are avilable for exchanging the handler > +details. Devices can create or join access groups using token-based authentication, ensuring > +that only authorized devices within the same group can perform DMA transfers across processes > +or OS domains. > + > +API usage flow for setting up the access pair group for DMA between process#1 & process#2. > + > +Process#1 (Group Creator): > +-------------------------- > +Calls ``rte_dma_access_pair_group_create`` to establish a new access pair group, > +then shares the ``group_id``, ``token`` and ``domain_id`` with Process#2 via IPC. > + > +Process#2 (Group Joiner): > +------------------------- > +Receives the ``group_id`` and ``token`` from Process#1 and calls ``rte_dma_access_pair_group_join`` > +to join the group. > + > +Both Processes: > +--------------- > +Use ``rte_dma_access_pair_group_handler_get`` to obtain ``handler`` information for domains > +in the group. > + > +--Perform inter-domain DMA transfers as required. > + > +Process#2 (when finished): > +-------------------------- > +Calls ``rte_dma_access_pair_group_leave`` to exit the group. > + > +Process#1 (final cleanup): > +-------------------------- > +Calls ``rte_dma_access_pair_group_destroy`` to destroy the group. > + > diff --git a/lib/dmadev/rte_dmadev.c b/lib/dmadev/rte_dmadev.c > index 30c3db3a98..cf50d7433c 100644 > --- a/lib/dmadev/rte_dmadev.c > +++ b/lib/dmadev/rte_dmadev.c > @@ -816,6 +816,144 @@ rte_dma_vchan_status(int16_t dev_id, uint16_t vchan, enum rte_dma_vchan_status * > return dev->dev_ops->vchan_status(dev, vchan, status); > } > > +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) > +{ > + struct rte_dma_info dev_info; > + struct rte_dma_dev *dev; > + > + if (!rte_dma_is_valid(dev_id) || group_id == NULL) > + return -EINVAL; > + dev = &rte_dma_devices[dev_id]; > + > + if (rte_dma_info_get(dev_id, &dev_info)) { > + RTE_DMA_LOG(ERR, "Device %d get device info fail", dev_id); > + return -EINVAL; > + } > + > + if (!((dev_info.dev_capa & RTE_DMA_CAPA_INTER_PROCESS_DOMAIN) || > + (dev_info.dev_capa & RTE_DMA_CAPA_INTER_OS_DOMAIN))) { > + RTE_DMA_LOG(ERR, "Device %d don't support inter-process or inter-os domain", > + dev_id); > + return -EINVAL; > + } > + > + if (*dev->dev_ops->access_pair_group_create == NULL) > + return -ENOTSUP; > + return (*dev->dev_ops->access_pair_group_create)(dev, domain_id, token, group_id, cb); > +} > + > +int > +rte_dma_access_pair_group_destroy(int16_t dev_id, int16_t group_id) > +{ > + struct rte_dma_info dev_info; > + struct rte_dma_dev *dev; > + > + if (!rte_dma_is_valid(dev_id)) > + return -EINVAL; > + dev = &rte_dma_devices[dev_id]; > + > + if (rte_dma_info_get(dev_id, &dev_info)) { > + RTE_DMA_LOG(ERR, "Device %d get device info fail", dev_id); > + return -EINVAL; > + } > + > + if (!((dev_info.dev_capa & RTE_DMA_CAPA_INTER_PROCESS_DOMAIN) || > + (dev_info.dev_capa & RTE_DMA_CAPA_INTER_OS_DOMAIN))) { > + RTE_DMA_LOG(ERR, "Device %d don't support inter-process or inter-os domain", > + dev_id); > + return -EINVAL; > + } > + > + if (*dev->dev_ops->access_pair_group_destroy == NULL) > + return -ENOTSUP; > + return (*dev->dev_ops->access_pair_group_destroy)(dev, group_id); > +} > + > +int > +rte_dma_access_pair_group_join(int16_t dev_id, int16_t group_id, rte_uuid_t token, > + rte_dma_access_pair_group_event_cb_t cb) > +{ > + struct rte_dma_info dev_info; > + struct rte_dma_dev *dev; > + > + if (!rte_dma_is_valid(dev_id)) > + return -EINVAL; > + dev = &rte_dma_devices[dev_id]; > + > + if (rte_dma_info_get(dev_id, &dev_info)) { > + RTE_DMA_LOG(ERR, "Device %d get device info fail", dev_id); > + return -EINVAL; > + } > + > + if (!((dev_info.dev_capa & RTE_DMA_CAPA_INTER_PROCESS_DOMAIN) || > + (dev_info.dev_capa & RTE_DMA_CAPA_INTER_OS_DOMAIN))) { > + RTE_DMA_LOG(ERR, "Device %d don't support inter-process or inter-os domain", > + dev_id); > + return -EINVAL; > + } > + > + if (*dev->dev_ops->access_pair_group_join == NULL) > + return -ENOTSUP; > + return (*dev->dev_ops->access_pair_group_join)(dev, group_id, token, cb); > +} > + > +int > +rte_dma_access_pair_group_leave(int16_t dev_id, int16_t group_id) > +{ > + struct rte_dma_info dev_info; > + struct rte_dma_dev *dev; > + > + if (!rte_dma_is_valid(dev_id)) > + return -EINVAL; > + dev = &rte_dma_devices[dev_id]; > + > + if (rte_dma_info_get(dev_id, &dev_info)) { > + RTE_DMA_LOG(ERR, "Device %d get device info fail", dev_id); > + return -EINVAL; > + } > + > + if (!((dev_info.dev_capa & RTE_DMA_CAPA_INTER_PROCESS_DOMAIN) || > + (dev_info.dev_capa & RTE_DMA_CAPA_INTER_OS_DOMAIN))) { > + RTE_DMA_LOG(ERR, "Device %d don't support inter-process or inter-os domain", > + dev_id); > + return -EINVAL; > + } > + > + if (*dev->dev_ops->access_pair_group_leave == NULL) > + return -ENOTSUP; > + return (*dev->dev_ops->access_pair_group_leave)(dev, group_id); > +} > + > +int > +rte_dma_access_pair_group_handler_get(int16_t dev_id, int16_t group_id, rte_uuid_t domain_id, > + uint16_t *handler) > +{ > + struct rte_dma_info dev_info; > + struct rte_dma_dev *dev; > + > + if (!rte_dma_is_valid(dev_id) || handler == NULL) > + return -EINVAL; > + dev = &rte_dma_devices[dev_id]; > + > + if (rte_dma_info_get(dev_id, &dev_info)) { > + RTE_DMA_LOG(ERR, "Device %d get device info fail", dev_id); > + return -EINVAL; > + } > + > + if (!((dev_info.dev_capa & RTE_DMA_CAPA_INTER_PROCESS_DOMAIN) || > + (dev_info.dev_capa & RTE_DMA_CAPA_INTER_OS_DOMAIN))) { > + RTE_DMA_LOG(ERR, "Device %d don't support inter-process or inter-os domain", > + dev_id); > + return -EINVAL; > + } > + > + if (*dev->dev_ops->access_pair_group_handler_get == NULL) > + return -ENOTSUP; > + return (*dev->dev_ops->access_pair_group_handler_get)(dev, group_id, domain_id, handler); > +} > + > static const char * > dma_capability_name(uint64_t capability) > { > diff --git a/lib/dmadev/rte_dmadev.h b/lib/dmadev/rte_dmadev.h > index 1708311c5b..77c19b2008 100644 > --- a/lib/dmadev/rte_dmadev.h > +++ b/lib/dmadev/rte_dmadev.h > @@ -148,6 +148,7 @@ > > #include > #include > +#include > > #ifdef __cplusplus > extern "C" { > @@ -797,6 +798,142 @@ rte_dma_vchan_status(int16_t dev_id, uint16_t vchan, enum rte_dma_vchan_status * > */ > int rte_dma_dump(int16_t dev_id, FILE *f); > > +/** > + * Event types for DMA access pair group notifications. > + * > + * 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. > + */ > +enum rte_dma_access_pair_group_event_type { > + /** A member left the group (notifies creator and joiners) */ > + RTE_DMA_GROUP_EVENT_MEMBER_LEFT, > + /** Group was destroyed (notifies joiners) */ > + RTE_DMA_GROUP_EVENT_GROUP_DESTROYED > +}; > + > +/** > + * 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. > + * > + * 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. > + * > + * @param dev_id > + * Identifier of the DMA device. > + * @param group_id > + * Identifier of the access pair group where the event occurred. > + * @param 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. > + * @param event > + * Type of event that occurred. > + * @see rte_dma_access_pair_group_event_type > + */ > +typedef void (*rte_dma_access_pair_group_event_cb_t)(int16_t dma_id, int16_t group_id, > + rte_uuid_t domain_id, > + enum > + rte_dma_access_pair_group_event_type event); > + > +/** > + * Create an access pair group to enable secure DMA transfers between devices across different > + * processes or operating system domains. > + * > + * @param dev_id > + * Identifier of the DMA device initiating the group. > + * @param domain_id > + * Unique identifier representing the process or OS domain. > + * @param token > + * Authentication token used to establish the access group. > + * @param[out] group_id > + * Pointer to store the ID of the newly created access group. > + * @param cb > + * Callback function to be invoked when a member leaves the group. > + * > + * @return > + * 0 on success, > + * negative error code on failure. > + */ > +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); > + > +/** > + * Destroy an access pair group if all participating devices have exited. This operation is only > + * permitted by the device that originally created the group; attempts by other devices will result > + * in failure. > + * > + * @param dev_id > + * Identifier of the device requesting group destruction. > + * @param group_id > + * ID of the access group to be destroyed. > + * @return > + * 0 on success, > + * negative value on failure indicating the error code. > + */ > +int rte_dma_access_pair_group_destroy(int16_t dev_id, int16_t group_id); > + > +/** > + * Join an existing access group to enable secure DMA transfers between devices across different > + * processes or OS domains. > + * > + * @param dev_id > + * Identifier of the DMA device attempting to join the group. > + * @param group_id > + * ID of the access group to join. > + * @param token > + * Authentication token used to validate group membership. > + * @param cb > + * Callback function to be invoked when the device leaves the group or when the group > + * is destroyed due to some exception or failure. > + * > + * @return > + * 0 on success, > + * negative value on failure indicating the error code. > + */ > +int rte_dma_access_pair_group_join(int16_t dev_id, int16_t group_id, rte_uuid_t token, > + rte_dma_access_pair_group_event_cb_t cb); > + > +/** > + * Leave an access group, removing the device's entry from the group table and disabling > + * inter-domain DMA transfers to and from this device. This operation is not permitted for the > + * device that originally created the group. > + * > + * @param dev_id > + * Identifier of the device requesting to leave the group. > + * @param group_id > + * ID of the access group to leave. > + * @return > + * 0 on success, > + * negative value on failure indicating the error code. > + */ > +int rte_dma_access_pair_group_leave(int16_t dev_id, int16_t group_id); > + > +/** > + * 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. > + * > + * @param dev_id > + * Identifier of the DMA device requesting the handler. > + * @param group_id > + * ID of the access group to query. > + * @param group_tbl > + * Unique identifier of the target process or OS domain. > + * @param[out] handler > + * Pointer to store the retrieved handler value. > + * @return > + * 0 on success, > + * negative value on failure indicating the error code. > + */ > +int rte_dma_access_pair_group_handler_get(int16_t dev_id, int16_t group_id, rte_uuid_t domain_id, > + uint16_t *handler); > + > /** > * DMA transfer result status code defines. > * > diff --git a/lib/dmadev/rte_dmadev_pmd.h b/lib/dmadev/rte_dmadev_pmd.h > index 58729088ff..16fd625c2d 100644 > --- a/lib/dmadev/rte_dmadev_pmd.h > +++ b/lib/dmadev/rte_dmadev_pmd.h > @@ -64,6 +64,29 @@ typedef int (*rte_dma_vchan_status_t)(const struct rte_dma_dev *dev, uint16_t vc > /** @internal Used to dump internal information. */ > typedef int (*rte_dma_dump_t)(const struct rte_dma_dev *dev, FILE *f); > > +/** @internal Used to create an access pair group for inter-process or inter-OS DMA transfers. */ > +typedef int (*rte_dma_access_pair_group_create_t)(const struct rte_dma_dev *dev, > + rte_uuid_t domain_id, rte_uuid_t token, > + int16_t *group_id, > + rte_dma_access_pair_group_event_cb_t cb); > + > +/** @internal Used to destroy an access pair group when all other devices have exited. */ > +typedef int (*rte_dma_access_pair_group_destroy_t)(const struct rte_dma_dev *dev, > + int16_t group_id); > + > +/** @internal Used to join an access pair group for inter-process or inter-OS DMA transfers. */ > +typedef int (*rte_dma_access_pair_group_join_t)(const struct rte_dma_dev *dev, int16_t group_id, > + rte_uuid_t token, > + rte_dma_access_pair_group_event_cb_t cb); > + > +/** @internal Used to leave an access pair group, removing the device from the group. */ > +typedef int (*rte_dma_access_pair_group_leave_t)(const struct rte_dma_dev *dev, int16_t group_id); > + > +/** @internal Used to retrieve handler information of the domain_id present in the group. */ > +typedef int (*rte_dma_access_pair_group_handler_get_t)(const struct rte_dma_dev *dev, > + int16_t group_id, rte_uuid_t domain_id, > + uint16_t *handler); > + > /** > * DMA device operations function pointer table. > * > @@ -83,6 +106,12 @@ struct rte_dma_dev_ops { > > rte_dma_vchan_status_t vchan_status; > rte_dma_dump_t dev_dump; > + > + rte_dma_access_pair_group_create_t access_pair_group_create; > + rte_dma_access_pair_group_destroy_t access_pair_group_destroy; > + rte_dma_access_pair_group_join_t access_pair_group_join; > + rte_dma_access_pair_group_leave_t access_pair_group_leave; > + rte_dma_access_pair_group_handler_get_t access_pair_group_handler_get; > }; > > /** > diff --git a/lib/dmadev/rte_dmadev_trace.h b/lib/dmadev/rte_dmadev_trace.h > index f1a178eeb5..da80a8cb50 100644 > --- a/lib/dmadev/rte_dmadev_trace.h > +++ b/lib/dmadev/rte_dmadev_trace.h > @@ -101,6 +101,48 @@ RTE_TRACE_POINT( > rte_trace_point_emit_int(ret); > ) > > +RTE_TRACE_POINT( > + rte_dma_trace_access_pair_group_create, > + RTE_TRACE_POINT_ARGS(int16_t dev_id, rte_uuid_t domain_id, rte_uuid_t token, > + int16_t *group_id), > + rte_trace_point_emit_i16(dev_id); > + rte_trace_point_emit_u8_ptr(&domain_id[0]); > + rte_trace_point_emit_u8_ptr(&token[0]); > + rte_trace_point_emit_ptr(group_id); > +) > + > +RTE_TRACE_POINT( > + rte_dma_trace_access_pair_group_destroy, > + RTE_TRACE_POINT_ARGS(int16_t dev_id, int16_t group_id), > + rte_trace_point_emit_i16(dev_id); > + rte_trace_point_emit_i16(group_id); > +) > + > +RTE_TRACE_POINT( > + rte_dma_trace_access_pair_group_join, > + RTE_TRACE_POINT_ARGS(int16_t dev_id, int16_t group_id, rte_uuid_t token), > + rte_trace_point_emit_i16(dev_id); > + rte_trace_point_emit_i16(group_id); > + rte_trace_point_emit_u8_ptr(&token[0]); > +) > + > +RTE_TRACE_POINT( > + rte_dma_trace_access_pair_group_leave, > + RTE_TRACE_POINT_ARGS(int16_t dev_id, int16_t group_id), > + rte_trace_point_emit_i16(dev_id); > + rte_trace_point_emit_i16(group_id); > +) > + > +RTE_TRACE_POINT( > + rte_dma_trace_access_pair_group_handler_get, > + RTE_TRACE_POINT_ARGS(int16_t dev_id, int16_t group_id, rte_uuid_t domain_id, > + uint16_t *handler), > + rte_trace_point_emit_i16(dev_id); > + rte_trace_point_emit_i16(group_id); > + rte_trace_point_emit_u8_ptr(&domain_id[0]); > + rte_trace_point_emit_ptr(handler); > +) > + > #ifdef __cplusplus > } > #endif