linux-stable/kernel/bpf
Toke Høiland-Jørgensen 4a1e7c0c63 bpf: Support attaching freplace programs to multiple attach points
This enables support for attaching freplace programs to multiple attach
points. It does this by amending the UAPI for bpf_link_Create with a target
btf ID that can be used to supply the new attachment point along with the
target program fd. The target must be compatible with the target that was
supplied at program load time.

The implementation reuses the checks that were factored out of
check_attach_btf_id() to ensure compatibility between the BTF types of the
old and new attachment. If these match, a new bpf_tracing_link will be
created for the new attach target, allowing multiple attachments to
co-exist simultaneously.

The code could theoretically support multiple-attach of other types of
tracing programs as well, but since I don't have a use case for any of
those, there is no API support for doing so.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/160138355169.48470.17165680973640685368.stgit@toke.dk
2020-09-29 13:09:24 -07:00
..
preload bpf: Move prog->aux->linked_prog and trampoline into bpf_link on attach 2020-09-29 13:09:23 -07:00
arraymap.c bpf, x64: rework pro/epilogue and tailcall handling in JIT 2020-09-17 19:55:30 -07:00
bpf_inode_storage.c bpf: Allow specifying a BTF ID per argument in function protos 2020-09-21 15:00:40 -07:00
bpf_iter.c bpf: Bump iter seq size to support BTF representation of large data structures 2020-09-28 18:26:58 -07:00
bpf_local_storage.c bpf: Use hlist_add_head_rcu when linking to local_storage 2020-09-19 01:12:35 +02:00
bpf_lru_list.c
bpf_lru_list.h bpf: Fix a typo "inacitve" -> "inactive" 2020-04-06 21:54:10 +02:00
bpf_lsm.c bpf: Change bpf_sk_storage_*() to accept ARG_PTR_TO_BTF_ID_SOCK_COMMON 2020-09-25 13:58:01 -07:00
bpf_struct_ops.c bpf: Move btf_resolve_size into __btf_resolve_size 2020-08-25 15:37:41 -07:00
bpf_struct_ops_types.h
btf.c bpf: Move prog->aux->linked_prog and trampoline into bpf_link on attach 2020-09-29 13:09:23 -07:00
cgroup.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
core.c bpf: Move prog->aux->linked_prog and trampoline into bpf_link on attach 2020-09-29 13:09:23 -07:00
cpumap.c bpf, cpumap: Remove rcpu pointer from cpu_map_build_skb signature 2020-09-28 23:30:42 +02:00
devmap.c bpf: {cpu,dev}map: Change various functions return type from int to void 2020-09-01 15:45:58 +02:00
disasm.c
disasm.h
dispatcher.c bpf: Remove bpf_image tree 2020-03-13 12:49:52 -07:00
hashtab.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-09-22 16:45:34 -07:00
helpers.c bpf: Add bpf_snprintf_btf helper 2020-09-28 18:26:58 -07:00
inode.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-09-22 16:45:34 -07:00
local_storage.c bpf/local_storage: Fix build without CONFIG_CGROUP 2020-07-25 20:16:36 -07:00
lpm_trie.c bpf: Add map_meta_equal map ops 2020-08-28 15:41:30 +02:00
Makefile bpf: Implement bpf_local_storage for inodes 2020-08-25 15:00:04 -07:00
map_in_map.c bpf: Relax max_entries check for most of the inner map types 2020-08-28 15:41:30 +02:00
map_in_map.h bpf: Add map_meta_equal map ops 2020-08-28 15:41:30 +02:00
map_iter.c bpf: Implement link_query callbacks in map element iterators 2020-08-21 14:01:39 -07:00
net_namespace.c bpf: Add support for forced LINK_DETACH command 2020-08-01 20:38:28 -07:00
offload.c
percpu_freelist.c bpf: Dont iterate over possible CPUs with interrupts disabled 2020-02-24 16:18:20 -08:00
percpu_freelist.h
prog_iter.c bpf: Refactor bpf_iter_reg to have separate seq_info member 2020-07-25 20:16:32 -07:00
queue_stack_maps.c bpf: Add map_meta_equal map ops 2020-08-28 15:41:30 +02:00
reuseport_array.c bpf: Add map_meta_equal map ops 2020-08-28 15:41:30 +02:00
ringbuf.c bpf: Add map_meta_equal map ops 2020-08-28 15:41:30 +02:00
stackmap.c bpf: Allow specifying a BTF ID per argument in function protos 2020-09-21 15:00:40 -07:00
syscall.c bpf: Support attaching freplace programs to multiple attach points 2020-09-29 13:09:24 -07:00
sysfs_btf.c bpf: Support llvm-objcopy for vmlinux BTF 2020-03-19 12:32:38 +01:00
task_iter.c bpf: Avoid iterating duplicated files for task_file iterator 2020-09-02 16:40:33 +02:00
tnum.c bpf: Verifier, do explicit ALU32 bounds tracking 2020-03-30 14:59:53 -07:00
trampoline.c bpf: Move prog->aux->linked_prog and trampoline into bpf_link on attach 2020-09-29 13:09:23 -07:00
verifier.c bpf: Support attaching freplace programs to multiple attach points 2020-09-29 13:09:24 -07:00