drivers/net/ethernet/netronome/nfp/bpf/main.h

   1 /*
   2  * Copyright (C) 2016-2017 Netronome Systems, Inc.
   3  *
   4  * This software is dual licensed under the GNU General License Version 2,
   5  * June 1991 as shown in the file COPYING in the top-level directory of this
   6  * source tree or the BSD 2-Clause License provided below.  You have the
   7  * option to license this software under the complete terms of either license.
   8  *
   9  * The BSD 2-Clause License:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      1. Redistributions of source code must retain the above
  16  *         copyright notice, this list of conditions and the following
  17  *         disclaimer.
  18  *
  19  *      2. Redistributions in binary form must reproduce the above
  20  *         copyright notice, this list of conditions and the following
  21  *         disclaimer in the documentation and/or other materials
  22  *         provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 #ifndef __NFP_BPF_H__
  35 #define __NFP_BPF_H__ 1
  36
  37 #include <linux/bitfield.h>
  38 #include <linux/bpf.h>
  39 #include <linux/bpf_verifier.h>
  40 #include <linux/kernel.h>
  41 #include <linux/list.h>
  42 #include <linux/skbuff.h>
  43 #include <linux/types.h>
  44 #include <linux/wait.h>
  45
  46 #include "../nfp_asm.h"
  47 #include "fw.h"
  48
  49 /* For relocation logic use up-most byte of branch instruction as scratch
  50  * area.  Remember to clear this before sending instructions to HW!
  51  */
  52 #define OP_RELO_TYPE    0xff00000000000000ULL
  53
  54 enum nfp_relo_type {
  55         RELO_NONE = 0,
  56         /* standard internal jumps */
  57         RELO_BR_REL,
  58         /* internal jumps to parts of the outro */
  59         RELO_BR_GO_OUT,
  60         RELO_BR_GO_ABORT,
  61         /* external jumps to fixed addresses */
  62         RELO_BR_NEXT_PKT,
  63         RELO_BR_HELPER,
  64         /* immediate relocation against load address */
  65         RELO_IMMED_REL,
  66 };
  67
  68 /* To make absolute relocated branches (branches other than RELO_BR_REL)
  69  * distinguishable in user space dumps from normal jumps, add a large offset
  70  * to them.
  71  */
  72 #define BR_OFF_RELO             15000
  73
  74 enum static_regs {
  75         STATIC_REG_IMM          = 21, /* Bank AB */
  76         STATIC_REG_STACK        = 22, /* Bank A */
  77         STATIC_REG_PKT_LEN      = 22, /* Bank B */
  78 };
  79
  80 enum pkt_vec {
  81         PKT_VEC_PKT_LEN         = 0,
  82         PKT_VEC_PKT_PTR         = 2,
  83 };
  84
  85 #define pv_len(np)      reg_lm(1, PKT_VEC_PKT_LEN)
  86 #define pv_ctm_ptr(np)  reg_lm(1, PKT_VEC_PKT_PTR)
  87
  88 #define stack_reg(np)   reg_a(STATIC_REG_STACK)
  89 #define stack_imm(np)   imm_b(np)
  90 #define plen_reg(np)    reg_b(STATIC_REG_PKT_LEN)
  91 #define pptr_reg(np)    pv_ctm_ptr(np)
  92 #define imm_a(np)       reg_a(STATIC_REG_IMM)
  93 #define imm_b(np)       reg_b(STATIC_REG_IMM)
  94 #define imm_both(np)    reg_both(STATIC_REG_IMM)
  95
  96 #define NFP_BPF_ABI_FLAGS       reg_imm(0)
  97 #define   NFP_BPF_ABI_FLAG_MARK 1
  98
  99 /**
 100  * struct nfp_app_bpf - bpf app priv structure
 101  * @app:                backpointer to the app
 102  *
 103  * @tag_allocator:      bitmap of control message tags in use
 104  * @tag_alloc_next:     next tag bit to allocate
 105  * @tag_alloc_last:     next tag bit to be freed
 106  *
 107  * @cmsg_replies:       received cmsg replies waiting to be consumed
 108  * @cmsg_wq:            work queue for waiting for cmsg replies
 109  *
 110  * @map_list:           list of offloaded maps
 111  * @maps_in_use:        number of currently offloaded maps
 112  * @map_elems_in_use:   number of elements allocated to offloaded maps
 113  *
 114  * @adjust_head:        adjust head capability
 115  * @adjust_head.flags:          extra flags for adjust head
 116  * @adjust_head.off_min:        minimal packet offset within buffer required
 117  * @adjust_head.off_max:        maximum packet offset within buffer required
 118  * @adjust_head.guaranteed_sub: negative adjustment guaranteed possible
 119  * @adjust_head.guaranteed_add: positive adjustment guaranteed possible
 120  *
 121  * @maps:               map capability
 122  * @maps.types:                 supported map types
 123  * @maps.max_maps:              max number of maps supported
 124  * @maps.max_elems:             max number of entries in each map
 125  * @maps.max_key_sz:            max size of map key
 126  * @maps.max_val_sz:            max size of map value
 127  * @maps.max_elem_sz:           max size of map entry (key + value)
 128  *
 129  * @helpers:            helper addressess for various calls
 130  * @helpers.map_lookup:         map lookup helper address
 131  */
 132 struct nfp_app_bpf {
 133         struct nfp_app *app;
 134
 135         DECLARE_BITMAP(tag_allocator, U16_MAX + 1);
 136         u16 tag_alloc_next;
 137         u16 tag_alloc_last;
 138
 139         struct sk_buff_head cmsg_replies;
 140         struct wait_queue_head cmsg_wq;
 141
 142         struct list_head map_list;
 143         unsigned int maps_in_use;
 144         unsigned int map_elems_in_use;
 145
 146         struct nfp_bpf_cap_adjust_head {
 147                 u32 flags;
 148                 int off_min;
 149                 int off_max;
 150                 int guaranteed_sub;
 151                 int guaranteed_add;
 152         } adjust_head;
 153
 154         struct {
 155                 u32 types;
 156                 u32 max_maps;
 157                 u32 max_elems;
 158                 u32 max_key_sz;
 159                 u32 max_val_sz;
 160                 u32 max_elem_sz;
 161         } maps;
 162
 163         struct {
 164                 u32 map_lookup;
 165         } helpers;
 166 };
 167
 168 /**
 169  * struct nfp_bpf_map - private per-map data attached to BPF maps for offload
 170  * @offmap:     pointer to the offloaded BPF map
 171  * @bpf:        back pointer to bpf app private structure
 172  * @tid:        table id identifying map on datapath
 173  * @l:          link on the nfp_app_bpf->map_list list
 174  */
 175 struct nfp_bpf_map {
 176         struct bpf_offloaded_map *offmap;
 177         struct nfp_app_bpf *bpf;
 178         u32 tid;
 179         struct list_head l;
 180 };
 181
 182 struct nfp_prog;
 183 struct nfp_insn_meta;
 184 typedef int (*instr_cb_t)(struct nfp_prog *, struct nfp_insn_meta *);
 185
 186 #define nfp_prog_first_meta(nfp_prog)                                   \
 187         list_first_entry(&(nfp_prog)->insns, struct nfp_insn_meta, l)
 188 #define nfp_prog_last_meta(nfp_prog)                                    \
 189         list_last_entry(&(nfp_prog)->insns, struct nfp_insn_meta, l)
 190 #define nfp_meta_next(meta)     list_next_entry(meta, l)
 191 #define nfp_meta_prev(meta)     list_prev_entry(meta, l)
 192
 193 #define FLAG_INSN_IS_JUMP_DST   BIT(0)
 194
 195 /**
 196  * struct nfp_insn_meta - BPF instruction wrapper
 197  * @insn: BPF instruction
 198  * @ptr: pointer type for memory operations
 199  * @ldst_gather_len: memcpy length gathered from load/store sequence
 200  * @paired_st: the paired store insn at the head of the sequence
 201  * @ptr_not_const: pointer is not always constant
 202  * @jmp_dst: destination info for jump instructions
 203  * @func_id: function id for call instructions
 204  * @arg1: arg1 for call instructions
 205  * @arg2: arg2 for call instructions
 206  * @arg2_var_off: arg2 changes stack offset on different paths
 207  * @off: index of first generated machine instruction (in nfp_prog.prog)
 208  * @n: eBPF instruction number
 209  * @flags: eBPF instruction extra optimization flags
 210  * @skip: skip this instruction (optimized out)
 211  * @double_cb: callback for second part of the instruction
 212  * @l: link on nfp_prog->insns list
 213  */
 214 struct nfp_insn_meta {
 215         struct bpf_insn insn;
 216         union {
 217                 struct {
 218                         struct bpf_reg_state ptr;
 219                         struct bpf_insn *paired_st;
 220                         s16 ldst_gather_len;
 221                         bool ptr_not_const;
 222                 };
 223                 struct nfp_insn_meta *jmp_dst;
 224                 struct {
 225                         u32 func_id;
 226                         struct bpf_reg_state arg1;
 227                         struct bpf_reg_state arg2;
 228                         bool arg2_var_off;
 229                 };
 230         };
 231         unsigned int off;
 232         unsigned short n;
 233         unsigned short flags;
 234         bool skip;
 235         instr_cb_t double_cb;
 236
 237         struct list_head l;
 238 };
 239
 240 #define BPF_SIZE_MASK   0x18
 241
 242 static inline u8 mbpf_class(const struct nfp_insn_meta *meta)
 243 {
 244         return BPF_CLASS(meta->insn.code);
 245 }
 246
 247 static inline u8 mbpf_src(const struct nfp_insn_meta *meta)
 248 {
 249         return BPF_SRC(meta->insn.code);
 250 }
 251
 252 static inline u8 mbpf_op(const struct nfp_insn_meta *meta)
 253 {
 254         return BPF_OP(meta->insn.code);
 255 }
 256
 257 static inline u8 mbpf_mode(const struct nfp_insn_meta *meta)
 258 {
 259         return BPF_MODE(meta->insn.code);
 260 }
 261
 262 static inline bool is_mbpf_load(const struct nfp_insn_meta *meta)
 263 {
 264         return (meta->insn.code & ~BPF_SIZE_MASK) == (BPF_LDX | BPF_MEM);
 265 }
 266
 267 static inline bool is_mbpf_store(const struct nfp_insn_meta *meta)
 268 {
 269         return (meta->insn.code & ~BPF_SIZE_MASK) == (BPF_STX | BPF_MEM);
 270 }
 271
 272 /**
 273  * struct nfp_prog - nfp BPF program
 274  * @bpf: backpointer to the bpf app priv structure
 275  * @prog: machine code
 276  * @prog_len: number of valid instructions in @prog array
 277  * @__prog_alloc_len: alloc size of @prog array
 278  * @verifier_meta: temporary storage for verifier's insn meta
 279  * @type: BPF program type
 280  * @last_bpf_off: address of the last instruction translated from BPF
 281  * @tgt_out: jump target for normal exit
 282  * @tgt_abort: jump target for abort (e.g. access outside of packet buffer)
 283  * @n_translated: number of successfully translated instructions (for errors)
 284  * @error: error code if something went wrong
 285  * @stack_depth: max stack depth from the verifier
 286  * @adjust_head_location: if program has single adjust head call - the insn no.
 287  * @insns: list of BPF instruction wrappers (struct nfp_insn_meta)
 288  */
 289 struct nfp_prog {
 290         struct nfp_app_bpf *bpf;
 291
 292         u64 *prog;
 293         unsigned int prog_len;
 294         unsigned int __prog_alloc_len;
 295
 296         struct nfp_insn_meta *verifier_meta;
 297
 298         enum bpf_prog_type type;
 299
 300         unsigned int last_bpf_off;
 301         unsigned int tgt_out;
 302         unsigned int tgt_abort;
 303
 304         unsigned int n_translated;
 305         int error;
 306
 307         unsigned int stack_depth;
 308         unsigned int adjust_head_location;
 309
 310         struct list_head insns;
 311 };
 312
 313 /**
 314  * struct nfp_bpf_vnic - per-vNIC BPF priv structure
 315  * @tc_prog:    currently loaded cls_bpf program
 316  * @start_off:  address of the first instruction in the memory
 317  * @tgt_done:   jump target to get the next packet
 318  */
 319 struct nfp_bpf_vnic {
 320         struct bpf_prog *tc_prog;
 321         unsigned int start_off;
 322         unsigned int tgt_done;
 323 };
 324
 325 void nfp_bpf_jit_prepare(struct nfp_prog *nfp_prog, unsigned int cnt);
 326 int nfp_bpf_jit(struct nfp_prog *prog);
 327 bool nfp_bpf_supported_opcode(u8 code);
 328
 329 extern const struct bpf_prog_offload_ops nfp_bpf_analyzer_ops;
 330
 331 struct netdev_bpf;
 332 struct nfp_app;
 333 struct nfp_net;
 334
 335 int nfp_ndo_bpf(struct nfp_app *app, struct nfp_net *nn,
 336                 struct netdev_bpf *bpf);
 337 int nfp_net_bpf_offload(struct nfp_net *nn, struct bpf_prog *prog,
 338                         bool old_prog, struct netlink_ext_ack *extack);
 339
 340 struct nfp_insn_meta *
 341 nfp_bpf_goto_meta(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
 342                   unsigned int insn_idx, unsigned int n_insns);
 343
 344 void *nfp_bpf_relo_for_vnic(struct nfp_prog *nfp_prog, struct nfp_bpf_vnic *bv);
 345
 346 long long int
 347 nfp_bpf_ctrl_alloc_map(struct nfp_app_bpf *bpf, struct bpf_map *map);
 348 void
 349 nfp_bpf_ctrl_free_map(struct nfp_app_bpf *bpf, struct nfp_bpf_map *nfp_map);
 350 int nfp_bpf_ctrl_getfirst_entry(struct bpf_offloaded_map *offmap,
 351                                 void *next_key);
 352 int nfp_bpf_ctrl_update_entry(struct bpf_offloaded_map *offmap,
 353                               void *key, void *value, u64 flags);
 354 int nfp_bpf_ctrl_del_entry(struct bpf_offloaded_map *offmap, void *key);
 355 int nfp_bpf_ctrl_lookup_entry(struct bpf_offloaded_map *offmap,
 356                               void *key, void *value);
 357 int nfp_bpf_ctrl_getnext_entry(struct bpf_offloaded_map *offmap,
 358                                void *key, void *next_key);
 359
 360 void nfp_bpf_ctrl_msg_rx(struct nfp_app *app, struct sk_buff *skb);
 361 #endif