summaryrefslogtreecommitdiff
path: root/drivers/net/ethernet/netronome/nfp/bpf/main.h
AgeCommit message (Collapse)AuthorFilesLines
2021-01-15bpf: Rename BPF_XADD and prepare to encode other atomics in .immBrendan Jackman1-2/+2
A subsequent patch will add additional atomic operations. These new operations will use the same opcode field as the existing XADD, with the immediate discriminating different operations. In preparation, rename the instruction mode BPF_ATOMIC and start calling the zero immediate BPF_ADD. This is possible (doesn't break existing valid BPF progs) because the immediate field is currently reserved MBZ and BPF_ADD is zero. All uses are removed from the tree but the BPF_XADD definition is kept around to avoid breaking builds for people including kernel headers. Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Björn Töpel <bjorn.topel@gmail.com> Link: https://lore.kernel.org/bpf/20210114181751.768687-5-jackmanb@google.com
2019-08-31nfp: bpf: add simple map op cacheJakub Kicinski1-0/+23
Each get_next and lookup call requires a round trip to the device. However, the device is capable of giving us a few entries back, instead of just one. In this patch we ask for a small yet reasonable number of entries (4) on every get_next call, and on subsequent get_next/lookup calls check this little cache for a hit. The cache is only kept for 250us, and is invalidated on every operation which may modify the map (e.g. delete or update call). Note that operations may be performed simultaneously, so we have to keep track of operations in flight. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-08-31nfp: bpf: rework MTU checkingJakub Kicinski1-0/+1
If control channel MTU is too low to support map operations a warning will be printed. This is not enough, we want to make sure probe fails in such scenario, as this would clearly be a faulty configuration. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-05-25nfp: bpf: eliminate zero extension code-genJiong Wang1-0/+2
This patch eliminate zero extension code-gen for instructions including both alu and load/store. The only exception is for ctx load, because offload target doesn't go through host ctx convert logic so we do customized load and ignores zext flag set by verifier. Cc: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-04-13nfp: split out common control message handling codeJakub Kicinski1-14/+3
BPF's control message handler seems like a good base to built on for request-reply control messages. Split it out to allow for reuse. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-27nfp: bpf: implement jitting of JMP32Jiong Wang1-2/+20
This patch implements code-gen for new JMP32 instructions on NFP. Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-01-24nfp: bpf: support removing dead codeJakub Kicinski1-1/+5
Add a verifier callback to the nfp JIT to remove the instructions the verifier deemed to be dead. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-01-24nfp: bpf: support optimizing dead branchesJakub Kicinski1-0/+14
Verifier will now optimize out branches to dead code, implement the replace_insn callback to take advantage of that optimization. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-01-24nfp: bpf: save original program lengthJakub Kicinski1-2/+4
Instead of passing env->prog->len around, and trying to adjust for optimized out instructions just save the initial number of instructions in struct nfp_prog. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-01-24nfp: bpf: split up the skip flagJakub Kicinski1-2/+7
We fail program loading if jump lands on a skipped instruction. This is for historical reasons, it used to be that we only skipped instructions optimized out based on prior context, and therefore the optimization would be buggy if we jumped directly to such instruction (because the context would be skipped by the jump). There are cases where instructions can be skipped without any context, for example there is no point in generating code for: r0 |= 0 We will also soon support dropping dead code, so make the skip logic differentiate between "optimized with preceding context" vs other skip types. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-11bpf: pass a struct with offload callbacks to bpf_offload_dev_create()Quentin Monnet1-1/+1
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 <jakub.kicinski@netronome.com> Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-11-11nfp: bpf: move nfp_bpf_analyzer_ops from verifier.c to offload.cQuentin Monnet1-0/+4
We are about to add several new callbacks to the struct, all of them defined in offload.c. Move the struct bpf_prog_offload_ops object in that file. As a consequence, nfp_verify_insn() and nfp_finalize() can no longer be static. Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-17nfp: bpf: double check vNIC capabilities after object sharingJakub Kicinski1-0/+3
Program translation stage checks that program can be offloaded to the netdev which was passed during the load (bpf_attr->prog_ifindex). After program sharing was introduced, however, the netdev on which program is loaded can theoretically be different, and therefore we should recheck the program size and max stack size at load time. This was found by code inspection, AFAIK today all vNICs have identical caps. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-17nfp: bpf: protect against mis-initializing atomic countersJakub Kicinski1-1/+6
Atomic operations on the NFP are currently always in big endian. The driver keeps track of regions of memory storing atomic values and byte swaps them accordingly. There are corner cases where the map values may be initialized before the driver knows they are used as atomic counters. This can happen either when the datapath is performing the update and the stack contents are unknown or when map is updated before the program which will use it for atomic values is loaded. To avoid situation where user initializes the value to 0 1 2 3 and then after loading a program which uses the word as an atomic counter starts reading 3 2 1 0 - only allow atomic counters to be initialized to endian-neutral values. For updates from the datapath the stack information may not be as precise, so just allow initializing such values to 0. Example code which would break: struct bpf_map_def SEC("maps") rxcnt = { .type = BPF_MAP_TYPE_HASH, .key_size = sizeof(__u32), .value_size = sizeof(__u64), .max_entries = 1, }; int xdp_prog1() { __u64 nonzeroval = 3; __u32 key = 0; __u64 *value; value = bpf_map_lookup_elem(&rxcnt, &key); if (!value) bpf_map_update_elem(&rxcnt, &key, &nonzeroval, BPF_ANY); else __sync_fetch_and_add(value, 1); return XDP_PASS; } $ offload bpftool map dump key: 00 00 00 00 value: 00 00 00 03 00 00 00 00 should be: $ offload bpftool map dump key: 00 00 00 00 value: 03 00 00 00 00 00 00 00 Reported-by: David Beckett <david.beckett@netronome.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-11nfp: replace long license headers with SPDXJakub Kicinski1-32/+2
Replace the repeated license text with SDPX identifiers. While at it bump the Copyright dates for files we touched this year. Signed-off-by: Edwin Peer <edwin.peer@netronome.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Nic Viljoen <nick.viljoen@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-08nfp: bpf: support pointers to other stack frames for BPF-to-BPF callsQuentin Monnet1-0/+1
Mark instructions that use pointers to areas in the stack outside of the current stack frame, and process them accordingly in mem_op_stack(). This way, we also support BPF-to-BPF calls where the caller passes a pointer to data in its own stack frame to the callee (typically, when the caller passes an address to one of its local variables located in the stack, as an argument). Thanks to Jakub and Jiong for figuring out how to deal with this case, I just had to turn their email discussion into this patch. Suggested-by: Jiong Wang <jiong.wang@netronome.com> Suggested-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-08nfp: bpf: optimise save/restore for R6~R9 based on register usageQuentin Monnet1-0/+2
When pre-processing the instructions, it is trivial to detect what subprograms are using R6, R7, R8 or R9 as destination registers. If a subprogram uses none of those, then we do not need to jump to the subroutines dedicated to saving and restoring callee-saved registers in its prologue and epilogue. This patch introduces detection of callee-saved registers in subprograms and prevents the JIT from adding calls to those subroutines whenever we can: we save some instructions in the translated program, and some time at runtime on BPF-to-BPF calls and returns. If no subprogram needs to save those registers, we can avoid appending the subroutines at the end of the program. Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-08nfp: bpf: update fixup function for BPF-to-BPF calls supportQuentin Monnet1-0/+2
Relocation for targets of BPF-to-BPF calls are required at the end of translation. Update the nfp_fixup_branches() function in that regard. When checking that the last instruction of each bloc is a branch, we must account for the length of the instructions required to pop the return address from the stack. Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-08nfp: bpf: add main logics for BPF-to-BPF calls support in nfp driverQuentin Monnet1-0/+20
This is the main patch for the logics of BPF-to-BPF calls in the nfp driver. The functions called on BPF_JUMP | BPF_CALL and BPF_JUMP | BPF_EXIT were used to call helpers and exit from the program, respectively; make them usable for calling into, or returning from, a BPF subprogram as well. For all calls, push the return address as well as the callee-saved registers (R6 to R9) to the stack, and pop them upon returning from the calls. In order to limit the overhead in terms of instruction number, this is done through dedicated subroutines. Jumping to the callee actually consists in jumping to the subroutine, that "returns" to the callee: this will require some fixup for passing the address in a later patch. Similarly, returning consists in jumping to the subroutine, which pops registers and then return directly to the caller (but no fixup is needed here). Return to the caller is performed with the RTN instruction newly added to the JIT. For the few steps where we need to know what subprogram an instruction belongs to, the struct nfp_insn_meta is extended with a new subprog_idx field. Note that checks on the available stack size, to take into account the additional requirements associated to BPF-to-BPF calls (storing R6-R9 and return addresses), are added in a later patch. Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-08nfp: bpf: account for BPF-to-BPF calls when preparing nfp JITQuentin Monnet1-1/+2
Similarly to "exit" or "helper call" instructions, BPF-to-BPF calls will require additional processing before translation starts, in order to record and mark jump destinations. We also mark the instructions where each subprogram begins. This will be used in a following commit to determine where to add prologues for subprograms. Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-08nfp: bpf: ignore helper-related checks for BPF calls in nfp verifierQuentin Monnet1-0/+8
The checks related to eBPF helper calls are performed each time the nfp driver meets a BPF_JUMP | BPF_CALL instruction. However, these checks are not relevant for BPF-to-BPF call (same instruction code, different value in source register), so just skip the checks for such calls. While at it, rename the function that runs those checks to make it clear they apply to _helper_ calls only. Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-08nfp: bpf: copy eBPF subprograms information from kernel verifierQuentin Monnet1-0/+12
In order to support BPF-to-BPF calls in offloaded programs, the nfp driver must collect information about the distinct subprograms: namely, the number of subprograms composing the complete program and the stack depth of those subprograms. The latter in particular is non-trivial to collect, so we copy those elements from the kernel verifier via the newly added post-verification hook. The struct nfp_prog is extended to store this information. Stack depths are stored in an array of dedicated structs. Subprogram start indexes are not collected. Instead, meta instructions associated to the start of a subprogram will be marked with a flag in a later patch. Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-08nfp: bpf: rename nfp_prog->stack_depth as nfp_prog->stack_frame_depthQuentin Monnet1-2/+2
In preparation for support for BPF to BPF calls in offloaded programs, rename the "stack_depth" field of the struct nfp_prog as "stack_frame_depth". This is to make it clear that the field refers to the maximum size of the current stack frame (as opposed to the maximum size of the whole stack memory). Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-02nfp: bpf: allow control message sizing for map opsJakub Kicinski1-0/+7
In current ABI the size of the messages carrying map elements was statically defined to at most 16 words of key and 16 words of value (NFP word is 4 bytes). We should not make this assumption and use the max key and value sizes from the BPF capability instead. To make sure old kernels don't get surprised with larger (or smaller) messages bump the FW ABI version to 3 when key/value size is different than 16 words. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-10-02nfp: bpf: parse global BPF ABI version capabilityJakub Kicinski1-0/+4
Up until now we only had per-vNIC BPF ABI version capabilities, which are slightly awkward to use because bulk of the resources and configuration does not relate to any particular vNIC. Add a new capability for global ABI version and check the per-vNIC version are equal to it. Assume the ABI version 2 if no explicit version capability is present. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-08-04nfp: bpf: xdp_adjust_tail supportJakub Kicinski1-0/+2
Add support for adjust_tail. There are no FW changes needed but add a FW capability just in case there would be any issue with previously released FW, or we will have to change the ABI in the future. The helper is trivial and shouldn't be used too often so just inline the body of the function. We add the delta to locally maintained packet length register and check for overflow, since add of negative value must overflow if result is positive. Note that if delta of 0 would be allowed in the kernel this trick stops working and we need one more instruction to compare lengths before and after the change. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-27nfp: bpf: remember maps by IDJakub Kicinski1-0/+3
Record perf maps by map ID, not raw kernel pointer. This helps with debug messages, because printing pointers to logs is frowned upon, and makes debug easier for the users, as map ID is something they should be more familiar with. Note that perf maps are offload neutral, therefore IDs won't be orphaned. While at it use a rate limited print helper for the error message. Reported-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-27nfp: bpf: allow receiving perf events on data queuesJakub Kicinski1-0/+3
Control queue is fairly low latency, and requires SKB allocations, which means we can't even reach 0.5Msps with perf events. Allow perf events to be delivered to data queues. This allows us to not only use multiple queues, but also receive and deliver to user space more than 5Msps per queue (Xeon E5-2630 v4 2.20GHz, no retpolines). Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-27nfp: bpf: pass raw data buffer to nfp_bpf_event_output()Jakub Kicinski1-1/+2
In preparation for SKB-less perf event handling make nfp_bpf_event_output() take buffer address and length, not SKB as parameters. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-18bpf: offload: keep the offload state per-ASICJakub Kicinski1-0/+4
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 <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-07nfp: bpf: support u32 divide using reciprocal_div.hJiong Wang1-0/+5
NFP doesn't have integer divide instruction, this patch use reciprocal algorithm (the basic one, reciprocal_div) to emulate it. For each u32 divide, we would need 11 instructions to finish the operation. 7 (for multiplication) + 4 (various ALUs) = 11 Given NFP only supports multiplication no bigger than u32, we'd require divisor and dividend no bigger than that as well. Also eBPF doesn't support signed divide and has enforced this on C language level by failing compilation. However LLVM assembler hasn't enforced this, so it is possible for negative constant to leak in as a BPF_K operand through assembly code, we reject such cases as well. Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-07nfp: bpf: support u16 and u32 multiplicationsJiong Wang1-0/+5
NFP supports u16 and u32 multiplication. Multiplication is done 8-bits per step, therefore we need 2 steps for u16 and 4 steps for u32. We also need one start instruction to initialize the sequence and one or two instructions to fetch the result depending on either you need the high halve of u32 multiplication. For ALU64, if either operand is beyond u32's value range, we reject it. One thing to note, if the source operand is BPF_K, then we need to check "imm" field directly, and we'd reject it if it is negative. Because for ALU64, "imm" (with s32 type) is expected to be sign extended to s64 which NFP mul doesn't support. For ALU32, it is fine for "imm" be negative though, because the result is 32-bits and here is no difference on the low halve of result for signed/unsigned mul, so we will get correct result. Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-07nfp: bpf: copy range info for all operands of all ALU operationsJiong Wang1-21/+12
NFP verifier hook is coping range information of the shift amount for indirect shift operation so optimized shift sequences could be generated. We want to use range info to do more things. For example, to decide whether multiplication and divide are supported on the given range. This patch simply let NFP verifier hook to copy range info for all operands of all ALU operands. Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-07nfp: bpf: rename umin/umax to umin_src/umax_srcJiong Wang1-5/+5
The two fields are a copy of umin and umax info of bpf_insn->src_reg generated by verifier. Rename to make their meaning clear. Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-18nfp: bpf: support logic indirect shifts (BPF_[L|R]SH | BPF_X)Jiong Wang1-0/+28
For indirect shifts, shift amount is not specified as constant, NFP needs to get the shift amount through the low 5 bits of source A operand in PREV_ALU, therefore extra instructions are needed compared with shifts by constants. Because NFP is 32-bit, so we are using register pair for 64-bit shifts and therefore would need different instruction sequences depending on whether shift amount is less than 32 or not. NFP branch-on-bit-test instruction emitter is added by this patch and is used for efficient runtime check on shift amount. We'd think the shift amount is less than 32 if bit 5 is clear and greater or equal than 32 otherwise. Shift amount is greater than or equal to 64 will result in undefined behavior. This patch also use range info to avoid generating unnecessary runtime code if we are certain shift amount is less than 32 or not. Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-09nfp: bpf: support setting the RX queue indexJakub Kicinski1-0/+8
BPF has access to all internal FW datapath structures. Including the structure containing RX queue selection. With little coordination with the datapath we can let the offloaded BPF select the RX queue. We just need a way to tell the datapath that queue selection has already been done and it shouldn't overwrite it. Define a bit to tell datapath BPF already selected a queue (QSEL_SET), if the selected queue is not enabled (>= number of enabled queues) datapath will perform normal RSS. BPF queue selection on the NIC can be used to replace standard datapath RSS with fully programmable BPF/XDP RSS. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-05nfp: bpf: perf event output helpers supportJakub Kicinski1-0/+4
Add support for the perf_event_output family of helpers. The implementation on the NFP will not match the host code exactly. The state of the host map and rings is unknown to the device, hence device can't return errors when rings are not installed. The device simply packs the data into a firmware notification message and sends it over to the host, returning success to the program. There is no notion of a host CPU on the device when packets are being processed. Device will only offload programs which set BPF_F_CURRENT_CPU. Still, if map index doesn't match CPU no error will be returned (see above). Dropped/lost firmware notification messages will not cause "lost events" event on the perf ring, they are only visible via device error counters. Firmware notification messages may also get reordered in respect to the packets which caused their generation. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-05nfp: bpf: record offload neutral maps in the driverJakub Kicinski1-1/+19
For asynchronous events originating from the device, like perf event output, we need to be able to make sure that objects being referred to by the FW message are valid on the host. FW events can get queued and reordered. Even if we had a FW message "barrier" we should still protect ourselves from bogus FW output. Add a reverse-mapping hash table and record in it all raw map pointers FW may refer to. Only record neutral maps, i.e. perf event arrays. These are currently the only objects FW can refer to. Use RCU protection on the read side, update side is under RTNL. Since program vs map destruction order is slightly painful for offload simply take an extra reference on all the recorded maps to make sure they don't disappear. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-25nfp: bpf: optimize comparisons to negative constantsJakub Kicinski1-1/+5
Comparison instruction requires a subtraction. If the constant is negative we are more likely to fit it into a NFP instruction directly if we change the sign and use addition. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-03-29nfp: bpf: add support for bpf_get_prandom_u32()Jakub Kicinski1-0/+4
NFP has a prng register, which we can read to obtain a u32 worth of pseudo random data. Generate code for it. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-03-29nfp: bpf: add support for atomic add of unknown valuesJakub Kicinski1-0/+7
Allow atomic add to be used even when the value is not guaranteed to fit into a 16 bit immediate. This requires the value to be pulled as data, and therefore use of a transfer register and a context swap. Track the information about possible lengths of the value, if it's guaranteed to be larger than 16bits don't generate the code for the optimized case at all. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-03-29nfp: bpf: add basic support for atomic addsJakub Kicinski1-0/+17
Implement atomic add operation for 32 and 64 bit values. Depend on the verifier to ensure alignment. Values have to be kept in big endian and swapped upon read/write. For now only support atomic add of a constant. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-03-29nfp: bpf: add map deletes from the datapathJakub Kicinski1-0/+2
Support calling map_delete_elem() FW helper from the datapath programs. For JIT checks and code are basically equivalent to map lookups. Similarly to other map helper key must be on the stack. Different pointer types are left for future extension. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-03-29nfp: bpf: add map updates from the datapathJakub Kicinski1-0/+2
Support calling map_update_elem() from the datapath programs by calling into FW-provided helper. Value pointer is passed in LM pointer #2. Keeping track of old state for arg3 is not necessary, since LM pointer #2 will be always loaded in this case, the trivial optimization for value at the bottom of the stack can't be done here. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-03-29nfp: bpf: add helper for validating stack pointersJakub Kicinski1-3/+11
Our implementation has restriction on stack pointers for function calls. Move the common checks into a helper for reuse. The state has to be encapsulated into a structure to support parameters other than BPF_REG_2. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-03-29nfp: bpf: detect packet reads could be cached, enable the optimisationJiong Wang1-0/+30
This patch is the front end of this optimisation, it detects and marks those packet reads that could be cached. Then the optimisation "backend" will be activated automatically. Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-03-29nfp: bpf: read from packet data cache for PTR_TO_PACKETJiong Wang1-0/+9
This patch assumes there is a packet data cache, and would try to read packet data from the cache instead of from memory. This patch only implements the optimisation "backend", it doesn't build the packet data cache, so this optimisation is not enabled. This patch has only enabled aligned packet data read, i.e. when the read offset to the start of cache is REG_WIDTH aligned. Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-06nfp: fix kdoc warnings on nested structuresJakub Kicinski1-12/+12
Commit 84ce5b987783 ("scripts: kernel-doc: improve nested logic to handle multiple identifiers") improved the handling of nested structure definitions in scripts/kernel-doc, and changed the expected format of documentation. This causes new warnings to appear on W=1 builds. Only comment changes. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-23nfp: bpf: use extack support to improve debuggingQuentin Monnet1-1/+1
Use the recently added extack support for eBPF offload in the driver. Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-17nfp: bpf: reject program on instructions unknown to the JIT compilerQuentin Monnet1-0/+1
If an eBPF instruction is unknown to the driver JIT compiler, we can reject the program at verification time. Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>