On 12/1/23 10:29 AM, Jamal Hadi Salim wrote:
We add an initial set of kfuncs to allow interactions from eBPF programs to the P4TC domain. - bpf_p4tc_tbl_read: Used to lookup a table entry from a BPF program installed in TC. To find the table entry we take in an skb, the pipeline ID, the table ID, a key and a key size. We use the skb to get the network namespace structure where all the pipelines are stored. After that we use the pipeline ID and the table ID, to find the table. We then use the key to search for the entry. We return an entry on success and NULL on failure. - xdp_p4tc_tbl_read: Used to lookup a table entry from a BPF program installed in XDP. To find the table entry we take in an xdp_md, the pipeline ID, the table ID, a key and a key size. We use struct xdp_md to get the network namespace structure where all the pipelines are stored. After that we use the pipeline ID and the table ID, to find the table. We then use the key to search for the entry. We return an entry on success and NULL on failure. - bpf_p4tc_entry_create: Used to create a table entry from a BPF program installed in TC. To create the table entry we take an skb, the pipeline ID, the table ID, a key and its size, and an action which will be associated with the new entry. We return 0 on success and a negative errno on failure - xdp_p4tc_entry_create: Used to create a table entry from a BPF program installed in XDP. To create the table entry we take an xdp_md, the pipeline ID, the table ID, a key and its size, and an action which will be associated with the new entry. We return 0 on success and a negative errno on failure - bpf_p4tc_entry_create_on_miss: conforms to PNA "add on miss". First does a lookup using the passed key and upon a miss will add the entry to the table. We return 0 on success and a negative errno on failure - xdp_p4tc_entry_create_on_miss: conforms to PNA "add on miss". First does a lookup using the passed key and upon a miss will add the entry to the table. We return 0 on success and a negative errno on failure - bpf_p4tc_entry_update: Used to update a table entry from a BPF program installed in TC. To update the table entry we take an skb, the pipeline ID, the table ID, a key and its size, and an action which will be associated with the new entry. We return 0 on success and a negative errno on failure - xdp_p4tc_entry_update: Used to update a table entry from a BPF program installed in XDP. To update the table entry we take an xdp_md, the pipeline ID, the table ID, a key and its size, and an action which will be associated with the new entry. We return 0 on success and a negative errno on failure - bpf_p4tc_entry_delete: Used to delete a table entry from a BPF program installed in TC. To delete the table entry we take an skb, the pipeline ID, the table ID, a key and a key size. We return 0 on success and a negative errno on failure - xdp_p4tc_entry_delete: Used to delete a table entry from a BPF program installed in XDP. To delete the table entry we take an xdp_md, the pipeline ID, the table ID, a key and a key size. We return 0 on success and a negative errno on failure
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+BTF_SET8_START(p4tc_kfunc_check_tbl_set_skb) +BTF_ID_FLAGS(func, bpf_p4tc_tbl_read, KF_RET_NULL); +BTF_ID_FLAGS(func, bpf_p4tc_entry_create); +BTF_ID_FLAGS(func, bpf_p4tc_entry_create_on_miss); +BTF_ID_FLAGS(func, bpf_p4tc_entry_update); +BTF_ID_FLAGS(func, bpf_p4tc_entry_delete); +BTF_SET8_END(p4tc_kfunc_check_tbl_set_skb)
These create/read/update/delete kfuncs are like defining a new hidden bpf map type in the kernel. bpf prog can now create its own link-list and rbtree. sched_ext has already been using it. This is the way the bpf prog should use instead of creating a new map type.
