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2023-03-07bpf: offload map memory usageYafang Shao1-0/+6
A new helper is introduced to calculate offload map memory usage. But currently the memory dynamically allocated in netdev dev_ops, like nsim_map_update_elem, is not counted. Let's just put it aside now. Signed-off-by: Yafang Shao <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>
2023-02-02bpf: Drop always true do_idr_lock parameter to bpf_map_free_idTobias Klauser1-1/+1
The do_idr_lock parameter to bpf_map_free_id was introduced by commit bd5f5f4ecb78 ("bpf: Add BPF_MAP_GET_FD_BY_ID"). However, all callers set do_idr_lock = true since commit 1e0bd5a091e5 ("bpf: Switch bpf_map ref counter to atomic64_t so bpf_map_inc() never fails"). While at it also inline __bpf_map_put into its only caller bpf_map_put now that do_idr_lock can be dropped from its signature. Signed-off-by: Tobias Klauser <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>
2023-01-28Merge tag 'for-netdev' of ↵Jakub Kicinski1-136/+283
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== bpf-next 2023-01-28 We've added 124 non-merge commits during the last 22 day(s) which contain a total of 124 files changed, 6386 insertions(+), 1827 deletions(-). The main changes are: 1) Implement XDP hints via kfuncs with initial support for RX hash and timestamp metadata kfuncs, from Stanislav Fomichev and Toke Høiland-Jørgensen. Measurements on overhead: https://lore.kernel.org/bpf/[email protected] 2) Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case, from Andrii Nakryiko. 3) Significantly reduce the search time for module symbols by livepatch and BPF, from Jiri Olsa and Zhen Lei. 4) Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals, from David Vernet. 5) Fix several issues in the dynptr processing such as stack slot liveness propagation, missing checks for PTR_TO_STACK variable offset, etc, from Kumar Kartikeya Dwivedi. 6) Various performance improvements, fixes, and introduction of more than just one XDP program to XSK selftests, from Magnus Karlsson. 7) Big batch to BPF samples to reduce deprecated functionality, from Daniel T. Lee. 8) Enable struct_ops programs to be sleepable in verifier, from David Vernet. 9) Reduce pr_warn() noise on BTF mismatches when they are expected under the CONFIG_MODULE_ALLOW_BTF_MISMATCH config anyway, from Connor O'Brien. 10) Describe modulo and division by zero behavior of the BPF runtime in BPF's instruction specification document, from Dave Thaler. 11) Several improvements to libbpf API documentation in libbpf.h, from Grant Seltzer. 12) Improve resolve_btfids header dependencies related to subcmd and add proper support for HOSTCC, from Ian Rogers. 13) Add ipip6 and ip6ip decapsulation support for bpf_skb_adjust_room() helper along with BPF selftests, from Ziyang Xuan. 14) Simplify the parsing logic of structure parameters for BPF trampoline in the x86-64 JIT compiler, from Pu Lehui. 15) Get BTF working for kernels with CONFIG_RUST enabled by excluding Rust compilation units with pahole, from Martin Rodriguez Reboredo. 16) Get bpf_setsockopt() working for kTLS on top of TCP sockets, from Kui-Feng Lee. 17) Disable stack protection for BPF objects in bpftool given BPF backends don't support it, from Holger Hoffstätte. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (124 commits) selftest/bpf: Make crashes more debuggable in test_progs libbpf: Add documentation to map pinning API functions libbpf: Fix malformed documentation formatting selftests/bpf: Properly enable hwtstamp in xdp_hw_metadata selftests/bpf: Calls bpf_setsockopt() on a ktls enabled socket. bpf: Check the protocol of a sock to agree the calls to bpf_setsockopt(). bpf/selftests: Verify struct_ops prog sleepable behavior bpf: Pass const struct bpf_prog * to .check_member libbpf: Support sleepable struct_ops.s section bpf: Allow BPF_PROG_TYPE_STRUCT_OPS programs to be sleepable selftests/bpf: Fix vmtest static compilation error tools/resolve_btfids: Alter how HOSTCC is forced tools/resolve_btfids: Install subcmd headers bpf/docs: Document the nocast aliasing behavior of ___init bpf/docs: Document how nested trusted fields may be defined bpf/docs: Document cpumask kfuncs in a new file selftests/bpf: Add selftest suite for cpumask kfuncs selftests/bpf: Add nested trust selftests suite bpf: Enable cpumasks to be queried and used as kptrs bpf: Disallow NULLable pointers for trusted kfuncs ... ==================== Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>
2023-01-23bpf: Support consuming XDP HW metadata from fext programsToke Høiland-Jørgensen1-30/+82
Instead of rejecting the attaching of PROG_TYPE_EXT programs to XDP programs that consume HW metadata, implement support for propagating the offload information. The extension program doesn't need to set a flag or ifindex, these will just be propagated from the target by the verifier. We need to create a separate offload object for the extension program, though, since it can be reattached to a different program later (which means we can't just inherit the offload information from the target). An additional check is added on attach that the new target is compatible with the offload information in the extension prog. Signed-off-by: Toke Høiland-Jørgensen <[email protected]> Signed-off-by: Stanislav Fomichev <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Martin KaFai Lau <[email protected]>
2023-01-23bpf: XDP metadata RX kfuncsStanislav Fomichev1-0/+44
Define a new kfunc set (xdp_metadata_kfunc_ids) which implements all possible XDP metatada kfuncs. Not all devices have to implement them. If kfunc is not supported by the target device, the default implementation is called instead. The verifier, at load time, replaces a call to the generic kfunc with a call to the per-device one. Per-device kfunc pointers are stored in separate struct xdp_metadata_ops. Cc: John Fastabend <[email protected]> Cc: David Ahern <[email protected]> Cc: Martin KaFai Lau <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Willem de Bruijn <[email protected]> Cc: Jesper Dangaard Brouer <[email protected]> Cc: Anatoly Burakov <[email protected]> Cc: Alexander Lobakin <[email protected]> Cc: Magnus Karlsson <[email protected]> Cc: Maryam Tahhan <[email protected]> Cc: [email protected] Cc: [email protected] Signed-off-by: Stanislav Fomichev <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Martin KaFai Lau <[email protected]>
2023-01-23bpf: Introduce device-bound XDP programsStanislav Fomichev1-24/+71
New flag BPF_F_XDP_DEV_BOUND_ONLY plus all the infra to have a way to associate a netdev with a BPF program at load time. netdevsim checks are dropped in favor of generic check in dev_xdp_attach. Cc: John Fastabend <[email protected]> Cc: David Ahern <[email protected]> Cc: Martin KaFai Lau <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Willem de Bruijn <[email protected]> Cc: Jesper Dangaard Brouer <[email protected]> Cc: Anatoly Burakov <[email protected]> Cc: Alexander Lobakin <[email protected]> Cc: Magnus Karlsson <[email protected]> Cc: Maryam Tahhan <[email protected]> Cc: [email protected] Cc: [email protected] Signed-off-by: Stanislav Fomichev <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Martin KaFai Lau <[email protected]>
2023-01-23bpf: Reshuffle some parts of bpf/offload.cStanislav Fomichev1-105/+117
To avoid adding forward declarations in the main patch, shuffle some code around. No functional changes. Cc: John Fastabend <[email protected]> Cc: David Ahern <[email protected]> Cc: Martin KaFai Lau <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Willem de Bruijn <[email protected]> Cc: Jesper Dangaard Brouer <[email protected]> Cc: Anatoly Burakov <[email protected]> Cc: Alexander Lobakin <[email protected]> Cc: Magnus Karlsson <[email protected]> Cc: Maryam Tahhan <[email protected]> Cc: [email protected] Cc: [email protected] Signed-off-by: Stanislav Fomichev <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Martin KaFai Lau <[email protected]>
2023-01-23bpf: Move offload initialization into late_initcallStanislav Fomichev1-15/+7
So we don't have to initialize it manually from several paths. Cc: John Fastabend <[email protected]> Cc: David Ahern <[email protected]> Cc: Martin KaFai Lau <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Willem de Bruijn <[email protected]> Cc: Jesper Dangaard Brouer <[email protected]> Cc: Anatoly Burakov <[email protected]> Cc: Alexander Lobakin <[email protected]> Cc: Magnus Karlsson <[email protected]> Cc: Maryam Tahhan <[email protected]> Cc: [email protected] Cc: [email protected] Signed-off-by: Stanislav Fomichev <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Martin KaFai Lau <[email protected]>
2023-01-23bpf: Rename bpf_{prog,map}_is_dev_bound to is_offloadedStanislav Fomichev1-2/+2
BPF offloading infra will be reused to implement bound-but-not-offloaded bpf programs. Rename existing helpers for clarity. No functional changes. Cc: John Fastabend <[email protected]> Cc: David Ahern <[email protected]> Cc: Martin KaFai Lau <[email protected]> Cc: Willem de Bruijn <[email protected]> Cc: Jesper Dangaard Brouer <[email protected]> Cc: Anatoly Burakov <[email protected]> Cc: Alexander Lobakin <[email protected]> Cc: Magnus Karlsson <[email protected]> Cc: Maryam Tahhan <[email protected]> Cc: [email protected] Cc: [email protected] Reviewed-by: Jakub Kicinski <[email protected]> Signed-off-by: Stanislav Fomichev <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Martin KaFai Lau <[email protected]>
2023-01-09bpf: restore the ebpf program ID for BPF_AUDIT_UNLOAD and ↵Paul Moore1-3/+0
PERF_BPF_EVENT_PROG_UNLOAD When changing the ebpf program put() routines to support being called from within IRQ context the program ID was reset to zero prior to calling the perf event and audit UNLOAD record generators, which resulted in problems as the ebpf program ID was bogus (always zero). This patch addresses this problem by removing an unnecessary call to bpf_prog_free_id() in __bpf_prog_offload_destroy() and adjusting __bpf_prog_put() to only call bpf_prog_free_id() after audit and perf have finished their bpf program unload tasks in bpf_prog_put_deferred(). For the record, no one can determine, or remember, why it was necessary to free the program ID, and remove it from the IDR, prior to executing bpf_prog_put_deferred(); regardless, both Stanislav and Alexei agree that the approach in this patch should be safe. It is worth noting that when moving the bpf_prog_free_id() call, the do_idr_lock parameter was forced to true as the ebpf devs determined this was the correct as the do_idr_lock should always be true. The do_idr_lock parameter will be removed in a follow-up patch, but it was kept here to keep the patch small in an effort to ease any stable backports. I also modified the bpf_audit_prog() logic used to associate the AUDIT_BPF record with other associated records, e.g. @ctx != NULL. Instead of keying off the operation, it now keys off the execution context, e.g. '!in_irg && !irqs_disabled()', which is much more appropriate and should help better connect the UNLOAD operations with the associated audit state (other audit records). Cc: [email protected] Fixes: d809e134be7a ("bpf: Prepare bpf_prog_put() to be called from irq context.") Reported-by: Burn Alting <[email protected]> Reported-by: Jiri Olsa <[email protected]> Suggested-by: Stanislav Fomichev <[email protected]> Suggested-by: Alexei Starovoitov <[email protected]> Signed-off-by: Paul Moore <[email protected]> Acked-by: Stanislav Fomichev <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>
2022-08-10bpf: Use bpf_map_area_alloc consistently on bpf map creationYafang Shao1-3/+3
Let's use the generic helper bpf_map_area_alloc() instead of the open-coded kzalloc helpers in bpf maps creation path. Signed-off-by: Yafang Shao <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>
2022-08-10bpf: Make __GFP_NOWARN consistent in bpf map creationYafang Shao1-1/+1
Some of the bpf maps are created with __GFP_NOWARN, i.e. arraymap, bloom_filter, bpf_local_storage, bpf_struct_ops, lpm_trie, queue_stack_maps, reuseport_array, stackmap and xskmap, while others are created without __GFP_NOWARN, i.e. cpumap, devmap, hashtab, local_storage, offload, ringbuf and sock_map. But there are not key differences between the creation of these maps. So let make this allocation flag consistent in all bpf maps creation. Then we can use a generic helper to alloc all bpf maps. Signed-off-by: Yafang Shao <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>
2020-02-17bpf, offload: Replace bitwise AND by logical AND in bpf_prog_offload_info_fillJohannes Krude1-1/+1
This if guards whether user-space wants a copy of the offload-jited bytecode and whether this bytecode exists. By erroneously doing a bitwise AND instead of a logical AND on user- and kernel-space buffer-size can lead to no data being copied to user-space especially when user-space size is a power of two and bigger then the kernel-space buffer. Fixes: fcfb126defda ("bpf: add new jited info fields in bpf_dev_offload and bpf_prog_info") Signed-off-by: Johannes Krude <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Jakub Kicinski <[email protected]> Link: https://lore.kernel.org/bpf/[email protected]
2019-12-08nsfs: clean-up ns_get_path() signature to return intAleksa Sarai1-6/+6
ns_get_path() and ns_get_path_cb() only ever return either NULL or an ERR_PTR. It is far more idiomatic to simply return an integer, and it makes all of the callers of ns_get_path() more straightforward to read. Fixes: e149ed2b805f ("take the targets of /proc/*/ns/* symlinks to separate fs") Signed-off-by: Aleksa Sarai <[email protected]> Signed-off-by: Al Viro <[email protected]>
2019-11-07bpf, offload: Unlock on error in bpf_offload_dev_create()Dan Carpenter1-1/+3
We need to drop the bpf_devs_lock on error before returning. Fixes: 9fd7c5559165 ("bpf: offload: aggregate offloads per-device") Signed-off-by: Dan Carpenter <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]> Acked-by: Jakub Kicinski <[email protected]> Link: https://lore.kernel.org/bpf/20191104091536.GB31509@mwanda
2019-02-12bpf: offload: add priv field for driversJakub Kicinski1-1/+9
Currently bpf_offload_dev does not have any priv pointer, forcing the drivers to work backwards from the netdev in program metadata. This is not great given programs are conceptually associated with the offload device, and it means one or two unnecessary deferences. Add a priv pointer to bpf_offload_dev. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2019-01-23bpf: notify offload JITs about optimizationsJakub Kicinski1-0/+35
Let offload JITs know when instructions are replaced and optimized out, so they can update their state appropriately. The optimizations are best effort, if JIT returns an error from any callback verifier will stop notifying it as state may now be out of sync, but the verifier continues making progress. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]>
2018-11-16bpf: fix null pointer dereference on pointer offloadColin Ian King1-2/+3
Pointer offload is being null checked however the following statement dereferences the potentially null pointer offload when assigning offload->dev_state. Fix this by only assigning it if offload is not null. Detected by CoverityScan, CID#1475437 ("Dereference after null check") Fixes: 00db12c3d141 ("bpf: call verifier_prep from its callback in struct bpf_offload_dev") Signed-off-by: Colin Ian King <[email protected]> Acked-by: Jakub Kicinski <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]>
2018-11-10bpf: do not pass netdev to translate() and prepare() offload callbacksQuentin Monnet1-2/+2
The kernel functions to prepare verifier and translate for offloaded program retrieve "offload" from "prog", and "netdev" from "offload". Then both "prog" and "netdev" are passed to the callbacks. Simplify this by letting the drivers retrieve the net device themselves from the offload object attached to prog - if they need it at all. There is currently no need to pass the netdev as an argument to those functions. Signed-off-by: Quentin Monnet <[email protected]> Reviewed-by: Jakub Kicinski <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]>
2018-11-10bpf: pass prog instead of env to bpf_prog_offload_verifier_prep()Quentin Monnet1-3/+3
Function bpf_prog_offload_verifier_prep(), called from the kernel BPF verifier to run a driver-specific callback for preparing for the verification step for offloaded programs, takes a pointer to a struct bpf_verifier_env object. However, no driver callback needs the whole structure at this time: the two drivers supporting this, nfp and netdevsim, only need a pointer to the struct bpf_prog instance held by env. Update the callback accordingly, on kernel side and in these two drivers. Signed-off-by: Quentin Monnet <[email protected]> Reviewed-by: Jakub Kicinski <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]>
2018-11-10bpf: pass destroy() as a callback and remove its ndo_bpf subcommandQuentin Monnet1-23/+1
As part of the transition from ndo_bpf() to callbacks attached to struct bpf_offload_dev for some of the eBPF offload operations, move the functions related to program destruction to the struct and remove the subcommand that was used to call them through the NDO. Remove function __bpf_offload_ndo(), which is no longer used. Signed-off-by: Quentin Monnet <[email protected]> Reviewed-by: Jakub Kicinski <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]>
2018-11-10bpf: pass translate() as a callback and remove its ndo_bpf subcommandQuentin Monnet1-7/+7
As part of the transition from ndo_bpf() to callbacks attached to struct bpf_offload_dev for some of the eBPF offload operations, move the functions related to code translation to the struct and remove the subcommand that was used to call them through the NDO. Signed-off-by: Quentin Monnet <[email protected]> Reviewed-by: Jakub Kicinski <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]>
2018-11-10bpf: call verifier_prep from its callback in struct bpf_offload_devQuentin Monnet1-13/+9
In a way similar to the change previously brought to the verify_insn hook and to the finalize callback, switch to the newly added ops in struct bpf_prog_offload for calling the functions used to prepare driver verifiers. Since the dev_ops pointer in struct bpf_prog_offload is no longer used by any callback, we can now remove it from struct bpf_prog_offload. Signed-off-by: Quentin Monnet <[email protected]> Reviewed-by: Jakub Kicinski <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]>
2018-11-10bpf: call finalize() from its callback in struct bpf_offload_devQuentin Monnet1-2/+2
In a way similar to the change previously brought to the verify_insn hook, switch to the newly added ops in struct bpf_prog_offload for calling the functions used to perform final verification steps for offloaded programs. Signed-off-by: Quentin Monnet <[email protected]> Reviewed-by: Jakub Kicinski <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]>
2018-11-10bpf: call verify_insn from its callback in struct bpf_offload_devQuentin Monnet1-1/+3
We intend to remove the dev_ops in struct bpf_prog_offload, and to only keep the ops in struct bpf_offload_dev instead, which is accessible from more locations for passing function pointers. But dev_ops is used for calling the verify_insn hook. Switch to the newly added ops in struct bpf_prog_offload instead. To avoid table lookups for each eBPF instruction to verify, we remember the offdev attached to a netdev and modify bpf_offload_find_netdev() to avoid performing more than once a lookup for a given offload object. Signed-off-by: Quentin Monnet <[email protected]> Reviewed-by: Jakub Kicinski <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]>
2018-11-10bpf: pass a struct with offload callbacks to bpf_offload_dev_create()Quentin Monnet1-1/+4
For passing device functions for offloaded eBPF programs, there used to be no place where to store the pointer without making the non-offloaded programs pay a memory price. As a consequence, three functions were called with ndo_bpf() through specific commands. Now that we have struct bpf_offload_dev, and since none of those operations rely on RTNL, we can turn these three commands into hooks inside the struct bpf_prog_offload_ops, and pass them as part of bpf_offload_dev_create(). This commit effectively passes a pointer to the struct to bpf_offload_dev_create(). We temporarily have two struct bpf_prog_offload_ops instances, one under offdev->ops and one under offload->dev_ops. The next patches will make the transition towards the former, so that offload->dev_ops can be removed, and callbacks relying on ndo_bpf() added to offdev->ops as well. While at it, rename "nfp_bpf_analyzer_ops" as "nfp_bpf_dev_ops" (and similarly for netdevsim). Suggested-by: Jakub Kicinski <[email protected]> Signed-off-by: Quentin Monnet <[email protected]> Reviewed-by: Jakub Kicinski <[email protected]> Signed-off-by: Alexei Starovoitov <[email protected]>
2018-10-08bpf: add verifier callback to get stack usage info for offloaded progsQuentin Monnet1-0/+18
In preparation for BPF-to-BPF calls in offloaded programs, add a new function attribute to the struct bpf_prog_offload_ops so that drivers supporting eBPF offload can hook at the end of program verification, and potentially extract information collected by the verifier. Implement a minimal callback (returning 0) in the drivers providing the structs, namely netdevsim and nfp. This will be useful in the nfp driver, in later commits, to extract the number of subprograms as well as the stack depth for those subprograms. Signed-off-by: Quentin Monnet <[email protected]> Reviewed-by: Jiong Wang <[email protected]> Reviewed-by: Jakub Kicinski <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2018-07-18bpf: offload: allow program and map sharing per-ASICJakub Kicinski1-7/+35
Allow programs and maps to be re-used across different netdevs, as long as they belong to the same struct bpf_offload_dev. Update the bpf_offload_prog_map_match() helper for the verifier and export a new helper for the drivers to use when checking programs at attachment time. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2018-07-18bpf: offload: keep the offload state per-ASICJakub Kicinski1-17/+64
Create a higher-level entity to represent a device/ASIC to allow programs and maps to be shared between device ports. The extra work is required to make sure we don't destroy BPF objects as soon as the netdev for which they were loaded gets destroyed, as other ports may still be using them. When netdev goes away all of its BPF objects will be moved to other netdevs of the device, and only destroyed when last netdev is unregistered. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2018-07-18bpf: offload: aggregate offloads per-deviceJakub Kicinski1-46/+96
Currently we have two lists of offloaded objects - programs and maps. Netdevice unregister notifier scans those lists to orphan objects associated with device being unregistered. This puts unnecessary (even if negligible) burden on all netdev unregister calls in BPF- -enabled kernel. The lists of objects may potentially get long making the linear scan even more problematic. There haven't been complaints about this mechanisms so far, but it is suboptimal. Instead of relying on notifiers, make the few BPF-capable drivers register explicitly for BPF offloads. The programs and maps will now be collected per-device not on a global list, and only scanned for removal when driver unregisters from BPF offloads. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2018-07-18bpf: offload: rename bpf_offload_dev_match() to bpf_offload_prog_map_match()Jakub Kicinski1-1/+1
A set of new API functions exported for the drivers will soon use 'bpf_offload_dev_' as a prefix. Rename the bpf_offload_dev_match() which is internal to the core (used by the verifier) to avoid any confusion. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2018-05-04bpf: offload: allow offloaded programs to use perf event arraysJakub Kicinski1-2/+4
BPF_MAP_TYPE_PERF_EVENT_ARRAY is special as far as offload goes. The map only holds glue to perf ring, not actual data. Allow non-offloaded perf event arrays to be used in offloaded programs. Offload driver can extract the events from HW and put them in the map for user space to retrieve. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Reviewed-by: Jiong Wang <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2018-01-18bpf: offload: report device information about offloaded mapsJakub Kicinski1-0/+55
Tell user space about device on which the map was created. Unfortunate reality of user ABI makes sharing this code with program offload difficult but the information is the same. Signed-off-by: Jakub Kicinski <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2018-01-18bpf: offload: allow array map offloadJakub Kicinski1-1/+2
The special handling of different map types is left to the driver. Allow offload of array maps by simply adding it to accepted types. For nfp we have to make sure array elements are not deleted. Signed-off-by: Jakub Kicinski <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2018-01-18bpf: add new jited info fields in bpf_dev_offload and bpf_prog_infoJiong Wang1-0/+23
For host JIT, there are "jited_len"/"bpf_func" fields in struct bpf_prog used by all host JIT targets to get jited image and it's length. While for offload, targets are likely to have different offload mechanisms that these info are kept in device private data fields. Therefore, BPF_OBJ_GET_INFO_BY_FD syscall needs an unified way to get JIT length and contents info for offload targets. One way is to introduce new callback to parse device private data then fill those fields in bpf_prog_info. This might be a little heavy, the other way is to add generic fields which will be initialized by all offload targets. This patch follow the second approach to introduce two new fields in struct bpf_dev_offload and teach bpf_prog_get_info_by_fd about them to fill correct jited_prog_len and jited_prog_insns in bpf_prog_info. Reviewed-by: Jakub Kicinski <[email protected]> Signed-off-by: Jiong Wang <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2018-01-17bpf: offload: make bpf_offload_dev_match() reject host+host caseJakub Kicinski1-3/+1
Daniel suggests it would be more logical for bpf_offload_dev_match() to return false is either the program or the map are not offloaded, rather than treating the both not offloaded case as a "matching CPU/host device". This makes no functional difference today, since verifier only calls bpf_offload_dev_match() when one of the objects is offloaded. Signed-off-by: Jakub Kicinski <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2018-01-14bpf: offload: add map offload infrastructureJakub Kicinski1-7/+181
BPF map offload follow similar path to program offload. At creation time users may specify ifindex of the device on which they want to create the map. Map will be validated by the kernel's .map_alloc_check callback and device driver will be called for the actual allocation. Map will have an empty set of operations associated with it (save for alloc and free callbacks). The real device callbacks are kept in map->offload->dev_ops because they have slightly different signatures. Map operations are called in process context so the driver may communicate with HW freely, msleep(), wait() etc. Map alloc and free callbacks are muxed via existing .ndo_bpf, and are always called with rtnl lock held. Maps and programs are guaranteed to be destroyed before .ndo_uninit (i.e. before unregister_netdev() returns). Map callbacks are invoked with bpf_devs_lock *read* locked, drivers must take care of exclusive locking if necessary. All offload-specific branches are marked with unlikely() (through bpf_map_is_dev_bound()), given that branch penalty will be negligible compared to IO anyway, and we don't want to penalize SW path unnecessarily. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2018-01-14bpf: offload: factor out netdev checking at allocation timeJakub Kicinski1-8/+20
Add a helper to check if netdev could be found and whether it has .ndo_bpf callback. There is no need to check the callback every time it's invoked, ndos can't reasonably be swapped for a set without .ndp_bpf while program is loaded. bpf_dev_offload_check() will also be used by map offload. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2018-01-14bpf: rename bpf_dev_offload -> bpf_prog_offloadJakub Kicinski1-5/+5
With map offload coming, we need to call program offload structure something less ambiguous. Pure rename, no functional changes. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2017-12-31bpf: offload: report device information for offloaded programsJakub Kicinski1-0/+59
Report to the user ifindex and namespace information of offloaded programs. If device has disappeared return -ENODEV. Specify the namespace using dev/inode combination. CC: Eric W. Biederman <[email protected]> Signed-off-by: Jakub Kicinski <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2017-12-31bpf: offload: free program id when device disappearsJakub Kicinski1-0/+3
Bound programs are quite useless after their device disappears. They are simply waiting for reference count to go to zero, don't list them in BPF_PROG_GET_NEXT_ID by freeing their ID early. Note that orphaned offload programs will return -ENODEV on BPF_OBJ_GET_INFO_BY_FD so user will never see ID 0. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2017-12-31bpf: offload: free prog->aux->offload when device disappearsJakub Kicinski1-14/+9
All bpf offload operations should now be under bpf_devs_lock, it's safe to free and clear the entire offload structure, not only the netdev pointer. __bpf_prog_offload_destroy() will no longer be called multiple times. Suggested-by: Alexei Starovoitov <[email protected]> Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2017-12-31bpf: offload: allow netdev to disappear while verifier is runningJakub Kicinski1-14/+16
To allow verifier instruction callbacks without any extra locking NETDEV_UNREGISTER notification would wait on a waitqueue for verifier to finish. This design decision was made when rtnl lock was providing all the locking. Use the read/write lock instead and remove the workqueue. Verifier will now call into the offload code, so dev_ops are moved to offload structure. Since verifier calls are all under bpf_prog_is_dev_bound() we no longer need static inline implementations to please builds with CONFIG_NET=n. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2017-12-31bpf: offload: don't require rtnl for dev list manipulationJakub Kicinski1-10/+24
We don't need the RTNL lock for all operations on offload state. We only need to hold it around ndo calls. The device offload initialization doesn't require it. The soon-to-come querying of the offload info will only need it partially. We will also be able to remove the waitqueue in following patches. Use struct rw_semaphore because map offload will require sleeping with the semaphore held for read. Suggested-by: Kirill Tkhai <[email protected]> Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2017-11-27bpf: offload: add a license headerJakub Kicinski1-0/+15
I forgot to add a license on kernel/bpf/offload.c. Luckily I'm still the only author so make it explicitly GPLv2. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Simon Horman <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2017-11-21bpf: revert report offload info to user spaceJakub Kicinski1-12/+0
This reverts commit bd601b6ada11 ("bpf: report offload info to user space"). The ifindex by itself is not sufficient, we should provide information on which network namespace this ifindex belongs to. After considering some options we concluded that it's best to just remove this API for now, and rework it in -next. Signed-off-by: Jakub Kicinski <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2017-11-21bpf: offload: ignore namespace movesJakub Kicinski1-0/+4
We are currently destroying the device offload state when device moves to another net namespace. This doesn't break with current NFP code, because offload state is not used on program removal, but it's not correct behaviour. Ignore the device unregister notifications on namespace move. Signed-off-by: Jakub Kicinski <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2017-11-21bpf: offload: rename the ifindex fieldJakub Kicinski1-1/+1
bpf_target_prog seems long and clunky, rename it to prog_ifindex. We don't want to call this field just ifindex, because maps may need a similar field in the future and bpf_attr members for programs and maps are unnamed. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Acked-by: Daniel Borkmann <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2017-11-21bpf: offload: limit offload to cls_bpf and xdp programs onlyJakub Kicinski1-2/+3
We are currently only allowing attachment of device-bound cls_bpf and XDP programs. Make this restriction explicit in the BPF offload code. This way we can potentially reuse the ifindex field in the future. Since XDP and cls_bpf programs can only be loaded by admin, we can drop the explicit capability check from offload code. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Acked-by: Daniel Borkmann <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>
2017-11-21bpf: offload: add comment warning developers about double destroyJakub Kicinski1-0/+4
Offload state may get destroyed either because the device for which it was constructed is going away, or because the refcount of bpf program itself has reached 0. In both of those cases we will call __bpf_prog_offload_destroy() to unlink the offload from the device. We may in fact call it twice, which works just fine, but we should make clear this is intended and caution others trying to extend the function. Signed-off-by: Jakub Kicinski <[email protected]> Reviewed-by: Quentin Monnet <[email protected]> Acked-by: Alexei Starovoitov <[email protected]> Acked-by: Daniel Borkmann <[email protected]> Signed-off-by: Daniel Borkmann <[email protected]>