with below comment fixed: Acked-by: Chengwen Feng <[email protected]>
On 10/13/2025 12:21 PM, Vamsi Krishna wrote: > From: Vamsi Attunuru <[email protected]> > > Modern DMA hardware supports data transfers between multiple DMA > devices, facilitating data communication across isolated domains, > containers, or operating systems. These DMA transfers function as > standard memory-to-memory operations, but with source or destination > addresses residing in different process or OS address space. The > exchange of these addresses between processes is handled through > private driver mechanism, which are beyond the scope of this > specification change. > > This commit introduces new capability flags to advertise driver support > for inter-process and inter-OS domain DMA transfers. It adds a mechanism > to specify source and destination handlers via the vchan configuration. > Until standardized control-plane APIs are defined for various categories > of DMA devices, these handler details can be exchanged through private > driver mechanisms. > > Signed-off-by: Vamsi Attunuru <[email protected]> > --- > V3 changes: > * Fix v2 review comments > V2 changes: > * Seperate out the control-plane APIs > * Address v0 review comments > * Add validation checks > * Rename the enums > > lib/dmadev/rte_dmadev.c | 19 +++++++++++ > lib/dmadev/rte_dmadev.h | 59 +++++++++++++++++++++++++++++++++++ > lib/dmadev/rte_dmadev_trace.h | 3 ++ > 3 files changed, 81 insertions(+) > > diff --git a/lib/dmadev/rte_dmadev.c b/lib/dmadev/rte_dmadev.c > index 17ee0808a9..d6792449bf 100644 > --- a/lib/dmadev/rte_dmadev.c > +++ b/lib/dmadev/rte_dmadev.c > @@ -659,6 +659,21 @@ rte_dma_vchan_setup(int16_t dev_id, uint16_t vchan, > RTE_DMA_LOG(ERR, "Device %d vchan out range!", dev_id); > return -EINVAL; > } > + if (conf->domain.type != RTE_DMA_INTER_DOMAIN_NONE && > + conf->direction != RTE_DMA_DIR_MEM_TO_MEM) { > + RTE_DMA_LOG(ERR, "Device %d inter domain only support > mem-to-mem transfer", dev_id); > + return -EINVAL; > + } > + if (conf->domain.type == RTE_DMA_INTER_OS_DOMAIN && > + !(dev_info.dev_capa & RTE_DMA_CAPA_INTER_OS_DOMAIN)) { > + RTE_DMA_LOG(ERR, "Device %d does not support inter os domain", > dev_id); > + return -EINVAL; > + } > + if (conf->domain.type == RTE_DMA_INTER_PROCESS_DOMAIN && > + !(dev_info.dev_capa & RTE_DMA_CAPA_INTER_PROCESS_DOMAIN)) { > + RTE_DMA_LOG(ERR, "Device %d does not support inter process > domain", dev_id); > + return -EINVAL; > + } > if (conf->direction != RTE_DMA_DIR_MEM_TO_MEM && > conf->direction != RTE_DMA_DIR_MEM_TO_DEV && > conf->direction != RTE_DMA_DIR_DEV_TO_MEM && > @@ -805,6 +820,8 @@ dma_capability_name(uint64_t capability) > { RTE_DMA_CAPA_HANDLES_ERRORS, "handles_errors" }, > { RTE_DMA_CAPA_M2D_AUTO_FREE, "m2d_auto_free" }, > { RTE_DMA_CAPA_PRI_POLICY_SP, "pri_policy_sp" }, > + { RTE_DMA_CAPA_INTER_PROCESS_DOMAIN, "inter_process_domain" }, > + { RTE_DMA_CAPA_INTER_OS_DOMAIN, "inter_os_domain" }, > { RTE_DMA_CAPA_OPS_COPY, "copy" }, > { RTE_DMA_CAPA_OPS_COPY_SG, "copy_sg" }, > { RTE_DMA_CAPA_OPS_FILL, "fill" }, > @@ -1014,6 +1031,8 @@ dmadev_handle_dev_info(const char *cmd __rte_unused, > ADD_CAPA(dma_caps, dev_capa, RTE_DMA_CAPA_HANDLES_ERRORS); > ADD_CAPA(dma_caps, dev_capa, RTE_DMA_CAPA_M2D_AUTO_FREE); > ADD_CAPA(dma_caps, dev_capa, RTE_DMA_CAPA_PRI_POLICY_SP); > + ADD_CAPA(dma_caps, dev_capa, RTE_DMA_CAPA_INTER_PROCESS_DOMAIN); > + ADD_CAPA(dma_caps, dev_capa, RTE_DMA_CAPA_INTER_OS_DOMAIN); > ADD_CAPA(dma_caps, dev_capa, RTE_DMA_CAPA_OPS_COPY); > ADD_CAPA(dma_caps, dev_capa, RTE_DMA_CAPA_OPS_COPY_SG); > ADD_CAPA(dma_caps, dev_capa, RTE_DMA_CAPA_OPS_FILL); > diff --git a/lib/dmadev/rte_dmadev.h b/lib/dmadev/rte_dmadev.h > index 550dbfbf75..4f735bb0c9 100644 > --- a/lib/dmadev/rte_dmadev.h > +++ b/lib/dmadev/rte_dmadev.h > @@ -265,6 +265,18 @@ int16_t rte_dma_next_dev(int16_t start_dev_id); > * known from 'nb_priorities' field in struct rte_dma_info. > */ > #define RTE_DMA_CAPA_PRI_POLICY_SP RTE_BIT64(8) > +/** Support inter-process DMA transfers. > + * > + * When this bit is set, the DMA device can perform memory transfers between > + * different process memory spaces. > + */ > +#define RTE_DMA_CAPA_INTER_PROCESS_DOMAIN RTE_BIT64(9) > +/** Support inter-OS domain DMA transfers. > + * > + * The DMA device can perform memory transfers across different operating > + * system domains. > + */ > +#define RTE_DMA_CAPA_INTER_OS_DOMAIN RTE_BIT64(10) > > /** Support copy operation. > * This capability start with index of 32, so that it could leave gap between > @@ -418,8 +430,13 @@ int rte_dma_close(int16_t dev_id); > */ > enum rte_dma_direction { > /** 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 struct rte_dma_vchan_conf::direction > + * @see struct rte_dma_inter_domain_param::type > */ > RTE_DMA_DIR_MEM_TO_MEM, > /** DMA transfer direction - from memory to device. > @@ -564,6 +581,39 @@ struct rte_dma_auto_free_param { > uint64_t reserved[2]; > }; > > +/** > + * Inter-DMA transfer domain type. > + * > + * 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 struct rte_dma_inter_domain_param:type > + */ > +enum rte_dma_inter_domain_type { > + /**< No inter-domain transfer; standard DMA within same domaini. */ > + RTE_DMA_INTER_DOMAIN_NONE, > + /**< Transfer occurs between different user-space processes. */ > + RTE_DMA_INTER_PROCESS_DOMAIN, > + /**< Transfer spans across different operating system domains. */ > + RTE_DMA_INTER_OS_DOMAIN, If comment located before define, it should prefix with ** not **< > +}; > + > +/** > + * Parameters for inter-process or inter-OS DMA transfers. > + * > + * This structure defines the parameters required to perform DMA transfers > + * across different domains, such as between processes or operating systems. > + * It includes the domain type and handler identifiers for both the source > + * and destination domains. I think we could add more comment about how to config use the src/dst handler. as I comment in before mail: It's mean local process if the src/dst_handler is zero? for example, I setup a inter-os domain param, if the src_handle is none zero and dst_handle is zero, then all DMA copy will from another OS to local process. all DMA fill will write to local process. If the src_handle is zero and dst_handle is non-zero, then all DMA copy will from local process to another OS domain all DMA fill will write to another OS domain. If both src_handle and dst_handle is non-zero, then all DMA copy will from another OS to another OS domain all DMA fill will write to another OS domain. > + */ > +struct rte_dma_inter_domain_param { > + enum rte_dma_inter_domain_type type; /**< Type of inter-domain. */ > + uint16_t src_handler; /**< Source domain handler identifier. */ > + uint16_t dst_handler; /**< Destination domain handler identifier. */ > + uint64_t reserved[2]; /**< Reserved for future fields. */ Please move above comment before define to keep the whole header-file consistency. > +}; > + > /** > * A structure used to configure a virtual DMA channel. > * > @@ -601,6 +651,15 @@ struct rte_dma_vchan_conf { > * @see struct rte_dma_auto_free_param > */ > struct rte_dma_auto_free_param auto_free; > + /** Parameters for inter-process or inter-OS domain DMA transfers. This > field > + * specifies the source and destination domain handlers required for DMA > + * operations that span across different processes or operating system > domains. > + * > + * @see RTE_DMA_CAPA_INTER_PROCESS_DOMAIN > + * @see RTE_DMA_CAPA_INTER_OS_DOMAIN > + * @see struct rte_dma_inter_domain_param > + */ > + struct rte_dma_inter_domain_param domain; > }; > > /** > diff --git a/lib/dmadev/rte_dmadev_trace.h b/lib/dmadev/rte_dmadev_trace.h > index 1de92655f2..fa619c4090 100644 > --- a/lib/dmadev/rte_dmadev_trace.h > +++ b/lib/dmadev/rte_dmadev_trace.h > @@ -79,6 +79,9 @@ RTE_TRACE_POINT( > rte_trace_point_emit_int(conf->dst_port.port_type); > rte_trace_point_emit_u64(conf->dst_port.pcie.val); > rte_trace_point_emit_ptr(conf->auto_free.m2d.pool); > + rte_trace_point_emit_int(conf->domain.type); > + rte_trace_point_emit_u16(conf->domain.src_handler); > + rte_trace_point_emit_u16(conf->domain.dst_handler); > rte_trace_point_emit_int(ret); > ) > BTW: please add the UT (test_dmadev_api.c) for above vchan_setup modify, this could be another commit I think.
