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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /tools/lib/bpf/gen_loader.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - 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. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'tools/lib/bpf/gen_loader.c')
-rw-r--r--tools/lib/bpf/gen_loader.c1121
1 files changed, 1121 insertions, 0 deletions
diff --git a/tools/lib/bpf/gen_loader.c b/tools/lib/bpf/gen_loader.c
new file mode 100644
index 000000000..23f5c4670
--- /dev/null
+++ b/tools/lib/bpf/gen_loader.c
@@ -0,0 +1,1121 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+/* Copyright (c) 2021 Facebook */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <linux/filter.h>
+#include <sys/param.h>
+#include "btf.h"
+#include "bpf.h"
+#include "libbpf.h"
+#include "libbpf_internal.h"
+#include "hashmap.h"
+#include "bpf_gen_internal.h"
+#include "skel_internal.h"
+#include <asm/byteorder.h>
+
+#define MAX_USED_MAPS 64
+#define MAX_USED_PROGS 32
+#define MAX_KFUNC_DESCS 256
+#define MAX_FD_ARRAY_SZ (MAX_USED_MAPS + MAX_KFUNC_DESCS)
+
+/* The following structure describes the stack layout of the loader program.
+ * In addition R6 contains the pointer to context.
+ * R7 contains the result of the last sys_bpf command (typically error or FD).
+ * R9 contains the result of the last sys_close command.
+ *
+ * Naming convention:
+ * ctx - bpf program context
+ * stack - bpf program stack
+ * blob - bpf_attr-s, strings, insns, map data.
+ * All the bytes that loader prog will use for read/write.
+ */
+struct loader_stack {
+ __u32 btf_fd;
+ __u32 inner_map_fd;
+ __u32 prog_fd[MAX_USED_PROGS];
+};
+
+#define stack_off(field) \
+ (__s16)(-sizeof(struct loader_stack) + offsetof(struct loader_stack, field))
+
+#define attr_field(attr, field) (attr + offsetof(union bpf_attr, field))
+
+static int blob_fd_array_off(struct bpf_gen *gen, int index)
+{
+ return gen->fd_array + index * sizeof(int);
+}
+
+static int realloc_insn_buf(struct bpf_gen *gen, __u32 size)
+{
+ size_t off = gen->insn_cur - gen->insn_start;
+ void *insn_start;
+
+ if (gen->error)
+ return gen->error;
+ if (size > INT32_MAX || off + size > INT32_MAX) {
+ gen->error = -ERANGE;
+ return -ERANGE;
+ }
+ insn_start = realloc(gen->insn_start, off + size);
+ if (!insn_start) {
+ gen->error = -ENOMEM;
+ free(gen->insn_start);
+ gen->insn_start = NULL;
+ return -ENOMEM;
+ }
+ gen->insn_start = insn_start;
+ gen->insn_cur = insn_start + off;
+ return 0;
+}
+
+static int realloc_data_buf(struct bpf_gen *gen, __u32 size)
+{
+ size_t off = gen->data_cur - gen->data_start;
+ void *data_start;
+
+ if (gen->error)
+ return gen->error;
+ if (size > INT32_MAX || off + size > INT32_MAX) {
+ gen->error = -ERANGE;
+ return -ERANGE;
+ }
+ data_start = realloc(gen->data_start, off + size);
+ if (!data_start) {
+ gen->error = -ENOMEM;
+ free(gen->data_start);
+ gen->data_start = NULL;
+ return -ENOMEM;
+ }
+ gen->data_start = data_start;
+ gen->data_cur = data_start + off;
+ return 0;
+}
+
+static void emit(struct bpf_gen *gen, struct bpf_insn insn)
+{
+ if (realloc_insn_buf(gen, sizeof(insn)))
+ return;
+ memcpy(gen->insn_cur, &insn, sizeof(insn));
+ gen->insn_cur += sizeof(insn);
+}
+
+static void emit2(struct bpf_gen *gen, struct bpf_insn insn1, struct bpf_insn insn2)
+{
+ emit(gen, insn1);
+ emit(gen, insn2);
+}
+
+static int add_data(struct bpf_gen *gen, const void *data, __u32 size);
+static void emit_sys_close_blob(struct bpf_gen *gen, int blob_off);
+
+void bpf_gen__init(struct bpf_gen *gen, int log_level, int nr_progs, int nr_maps)
+{
+ size_t stack_sz = sizeof(struct loader_stack), nr_progs_sz;
+ int i;
+
+ gen->fd_array = add_data(gen, NULL, MAX_FD_ARRAY_SZ * sizeof(int));
+ gen->log_level = log_level;
+ /* save ctx pointer into R6 */
+ emit(gen, BPF_MOV64_REG(BPF_REG_6, BPF_REG_1));
+
+ /* bzero stack */
+ emit(gen, BPF_MOV64_REG(BPF_REG_1, BPF_REG_10));
+ emit(gen, BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -stack_sz));
+ emit(gen, BPF_MOV64_IMM(BPF_REG_2, stack_sz));
+ emit(gen, BPF_MOV64_IMM(BPF_REG_3, 0));
+ emit(gen, BPF_EMIT_CALL(BPF_FUNC_probe_read_kernel));
+
+ /* amount of stack actually used, only used to calculate iterations, not stack offset */
+ nr_progs_sz = offsetof(struct loader_stack, prog_fd[nr_progs]);
+ /* jump over cleanup code */
+ emit(gen, BPF_JMP_IMM(BPF_JA, 0, 0,
+ /* size of cleanup code below (including map fd cleanup) */
+ (nr_progs_sz / 4) * 3 + 2 +
+ /* 6 insns for emit_sys_close_blob,
+ * 6 insns for debug_regs in emit_sys_close_blob
+ */
+ nr_maps * (6 + (gen->log_level ? 6 : 0))));
+
+ /* remember the label where all error branches will jump to */
+ gen->cleanup_label = gen->insn_cur - gen->insn_start;
+ /* emit cleanup code: close all temp FDs */
+ for (i = 0; i < nr_progs_sz; i += 4) {
+ emit(gen, BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_10, -stack_sz + i));
+ emit(gen, BPF_JMP_IMM(BPF_JSLE, BPF_REG_1, 0, 1));
+ emit(gen, BPF_EMIT_CALL(BPF_FUNC_sys_close));
+ }
+ for (i = 0; i < nr_maps; i++)
+ emit_sys_close_blob(gen, blob_fd_array_off(gen, i));
+ /* R7 contains the error code from sys_bpf. Copy it into R0 and exit. */
+ emit(gen, BPF_MOV64_REG(BPF_REG_0, BPF_REG_7));
+ emit(gen, BPF_EXIT_INSN());
+}
+
+static int add_data(struct bpf_gen *gen, const void *data, __u32 size)
+{
+ __u32 size8 = roundup(size, 8);
+ __u64 zero = 0;
+ void *prev;
+
+ if (realloc_data_buf(gen, size8))
+ return 0;
+ prev = gen->data_cur;
+ if (data) {
+ memcpy(gen->data_cur, data, size);
+ memcpy(gen->data_cur + size, &zero, size8 - size);
+ } else {
+ memset(gen->data_cur, 0, size8);
+ }
+ gen->data_cur += size8;
+ return prev - gen->data_start;
+}
+
+/* Get index for map_fd/btf_fd slot in reserved fd_array, or in data relative
+ * to start of fd_array. Caller can decide if it is usable or not.
+ */
+static int add_map_fd(struct bpf_gen *gen)
+{
+ if (gen->nr_maps == MAX_USED_MAPS) {
+ pr_warn("Total maps exceeds %d\n", MAX_USED_MAPS);
+ gen->error = -E2BIG;
+ return 0;
+ }
+ return gen->nr_maps++;
+}
+
+static int add_kfunc_btf_fd(struct bpf_gen *gen)
+{
+ int cur;
+
+ if (gen->nr_fd_array == MAX_KFUNC_DESCS) {
+ cur = add_data(gen, NULL, sizeof(int));
+ return (cur - gen->fd_array) / sizeof(int);
+ }
+ return MAX_USED_MAPS + gen->nr_fd_array++;
+}
+
+static int insn_bytes_to_bpf_size(__u32 sz)
+{
+ switch (sz) {
+ case 8: return BPF_DW;
+ case 4: return BPF_W;
+ case 2: return BPF_H;
+ case 1: return BPF_B;
+ default: return -1;
+ }
+}
+
+/* *(u64 *)(blob + off) = (u64)(void *)(blob + data) */
+static void emit_rel_store(struct bpf_gen *gen, int off, int data)
+{
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_0, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, data));
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, off));
+ emit(gen, BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, 0));
+}
+
+static void move_blob2blob(struct bpf_gen *gen, int off, int size, int blob_off)
+{
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_2, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, blob_off));
+ emit(gen, BPF_LDX_MEM(insn_bytes_to_bpf_size(size), BPF_REG_0, BPF_REG_2, 0));
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, off));
+ emit(gen, BPF_STX_MEM(insn_bytes_to_bpf_size(size), BPF_REG_1, BPF_REG_0, 0));
+}
+
+static void move_blob2ctx(struct bpf_gen *gen, int ctx_off, int size, int blob_off)
+{
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, blob_off));
+ emit(gen, BPF_LDX_MEM(insn_bytes_to_bpf_size(size), BPF_REG_0, BPF_REG_1, 0));
+ emit(gen, BPF_STX_MEM(insn_bytes_to_bpf_size(size), BPF_REG_6, BPF_REG_0, ctx_off));
+}
+
+static void move_ctx2blob(struct bpf_gen *gen, int off, int size, int ctx_off,
+ bool check_non_zero)
+{
+ emit(gen, BPF_LDX_MEM(insn_bytes_to_bpf_size(size), BPF_REG_0, BPF_REG_6, ctx_off));
+ if (check_non_zero)
+ /* If value in ctx is zero don't update the blob.
+ * For example: when ctx->map.max_entries == 0, keep default max_entries from bpf.c
+ */
+ emit(gen, BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 3));
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, off));
+ emit(gen, BPF_STX_MEM(insn_bytes_to_bpf_size(size), BPF_REG_1, BPF_REG_0, 0));
+}
+
+static void move_stack2blob(struct bpf_gen *gen, int off, int size, int stack_off)
+{
+ emit(gen, BPF_LDX_MEM(insn_bytes_to_bpf_size(size), BPF_REG_0, BPF_REG_10, stack_off));
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, off));
+ emit(gen, BPF_STX_MEM(insn_bytes_to_bpf_size(size), BPF_REG_1, BPF_REG_0, 0));
+}
+
+static void move_stack2ctx(struct bpf_gen *gen, int ctx_off, int size, int stack_off)
+{
+ emit(gen, BPF_LDX_MEM(insn_bytes_to_bpf_size(size), BPF_REG_0, BPF_REG_10, stack_off));
+ emit(gen, BPF_STX_MEM(insn_bytes_to_bpf_size(size), BPF_REG_6, BPF_REG_0, ctx_off));
+}
+
+static void emit_sys_bpf(struct bpf_gen *gen, int cmd, int attr, int attr_size)
+{
+ emit(gen, BPF_MOV64_IMM(BPF_REG_1, cmd));
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_2, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, attr));
+ emit(gen, BPF_MOV64_IMM(BPF_REG_3, attr_size));
+ emit(gen, BPF_EMIT_CALL(BPF_FUNC_sys_bpf));
+ /* remember the result in R7 */
+ emit(gen, BPF_MOV64_REG(BPF_REG_7, BPF_REG_0));
+}
+
+static bool is_simm16(__s64 value)
+{
+ return value == (__s64)(__s16)value;
+}
+
+static void emit_check_err(struct bpf_gen *gen)
+{
+ __s64 off = -(gen->insn_cur - gen->insn_start - gen->cleanup_label) / 8 - 1;
+
+ /* R7 contains result of last sys_bpf command.
+ * if (R7 < 0) goto cleanup;
+ */
+ if (is_simm16(off)) {
+ emit(gen, BPF_JMP_IMM(BPF_JSLT, BPF_REG_7, 0, off));
+ } else {
+ gen->error = -ERANGE;
+ emit(gen, BPF_JMP_IMM(BPF_JA, 0, 0, -1));
+ }
+}
+
+/* reg1 and reg2 should not be R1 - R5. They can be R0, R6 - R10 */
+static void emit_debug(struct bpf_gen *gen, int reg1, int reg2,
+ const char *fmt, va_list args)
+{
+ char buf[1024];
+ int addr, len, ret;
+
+ if (!gen->log_level)
+ return;
+ ret = vsnprintf(buf, sizeof(buf), fmt, args);
+ if (ret < 1024 - 7 && reg1 >= 0 && reg2 < 0)
+ /* The special case to accommodate common debug_ret():
+ * to avoid specifying BPF_REG_7 and adding " r=%%d" to
+ * prints explicitly.
+ */
+ strcat(buf, " r=%d");
+ len = strlen(buf) + 1;
+ addr = add_data(gen, buf, len);
+
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, addr));
+ emit(gen, BPF_MOV64_IMM(BPF_REG_2, len));
+ if (reg1 >= 0)
+ emit(gen, BPF_MOV64_REG(BPF_REG_3, reg1));
+ if (reg2 >= 0)
+ emit(gen, BPF_MOV64_REG(BPF_REG_4, reg2));
+ emit(gen, BPF_EMIT_CALL(BPF_FUNC_trace_printk));
+}
+
+static void debug_regs(struct bpf_gen *gen, int reg1, int reg2, const char *fmt, ...)
+{
+ va_list args;
+
+ va_start(args, fmt);
+ emit_debug(gen, reg1, reg2, fmt, args);
+ va_end(args);
+}
+
+static void debug_ret(struct bpf_gen *gen, const char *fmt, ...)
+{
+ va_list args;
+
+ va_start(args, fmt);
+ emit_debug(gen, BPF_REG_7, -1, fmt, args);
+ va_end(args);
+}
+
+static void __emit_sys_close(struct bpf_gen *gen)
+{
+ emit(gen, BPF_JMP_IMM(BPF_JSLE, BPF_REG_1, 0,
+ /* 2 is the number of the following insns
+ * * 6 is additional insns in debug_regs
+ */
+ 2 + (gen->log_level ? 6 : 0)));
+ emit(gen, BPF_MOV64_REG(BPF_REG_9, BPF_REG_1));
+ emit(gen, BPF_EMIT_CALL(BPF_FUNC_sys_close));
+ debug_regs(gen, BPF_REG_9, BPF_REG_0, "close(%%d) = %%d");
+}
+
+static void emit_sys_close_stack(struct bpf_gen *gen, int stack_off)
+{
+ emit(gen, BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_10, stack_off));
+ __emit_sys_close(gen);
+}
+
+static void emit_sys_close_blob(struct bpf_gen *gen, int blob_off)
+{
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_0, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, blob_off));
+ emit(gen, BPF_LDX_MEM(BPF_W, BPF_REG_1, BPF_REG_0, 0));
+ __emit_sys_close(gen);
+}
+
+int bpf_gen__finish(struct bpf_gen *gen, int nr_progs, int nr_maps)
+{
+ int i;
+
+ if (nr_progs < gen->nr_progs || nr_maps != gen->nr_maps) {
+ pr_warn("nr_progs %d/%d nr_maps %d/%d mismatch\n",
+ nr_progs, gen->nr_progs, nr_maps, gen->nr_maps);
+ gen->error = -EFAULT;
+ return gen->error;
+ }
+ emit_sys_close_stack(gen, stack_off(btf_fd));
+ for (i = 0; i < gen->nr_progs; i++)
+ move_stack2ctx(gen,
+ sizeof(struct bpf_loader_ctx) +
+ sizeof(struct bpf_map_desc) * gen->nr_maps +
+ sizeof(struct bpf_prog_desc) * i +
+ offsetof(struct bpf_prog_desc, prog_fd), 4,
+ stack_off(prog_fd[i]));
+ for (i = 0; i < gen->nr_maps; i++)
+ move_blob2ctx(gen,
+ sizeof(struct bpf_loader_ctx) +
+ sizeof(struct bpf_map_desc) * i +
+ offsetof(struct bpf_map_desc, map_fd), 4,
+ blob_fd_array_off(gen, i));
+ emit(gen, BPF_MOV64_IMM(BPF_REG_0, 0));
+ emit(gen, BPF_EXIT_INSN());
+ pr_debug("gen: finish %d\n", gen->error);
+ if (!gen->error) {
+ struct gen_loader_opts *opts = gen->opts;
+
+ opts->insns = gen->insn_start;
+ opts->insns_sz = gen->insn_cur - gen->insn_start;
+ opts->data = gen->data_start;
+ opts->data_sz = gen->data_cur - gen->data_start;
+ }
+ return gen->error;
+}
+
+void bpf_gen__free(struct bpf_gen *gen)
+{
+ if (!gen)
+ return;
+ free(gen->data_start);
+ free(gen->insn_start);
+ free(gen);
+}
+
+void bpf_gen__load_btf(struct bpf_gen *gen, const void *btf_raw_data,
+ __u32 btf_raw_size)
+{
+ int attr_size = offsetofend(union bpf_attr, btf_log_level);
+ int btf_data, btf_load_attr;
+ union bpf_attr attr;
+
+ memset(&attr, 0, attr_size);
+ pr_debug("gen: load_btf: size %d\n", btf_raw_size);
+ btf_data = add_data(gen, btf_raw_data, btf_raw_size);
+
+ attr.btf_size = btf_raw_size;
+ btf_load_attr = add_data(gen, &attr, attr_size);
+
+ /* populate union bpf_attr with user provided log details */
+ move_ctx2blob(gen, attr_field(btf_load_attr, btf_log_level), 4,
+ offsetof(struct bpf_loader_ctx, log_level), false);
+ move_ctx2blob(gen, attr_field(btf_load_attr, btf_log_size), 4,
+ offsetof(struct bpf_loader_ctx, log_size), false);
+ move_ctx2blob(gen, attr_field(btf_load_attr, btf_log_buf), 8,
+ offsetof(struct bpf_loader_ctx, log_buf), false);
+ /* populate union bpf_attr with a pointer to the BTF data */
+ emit_rel_store(gen, attr_field(btf_load_attr, btf), btf_data);
+ /* emit BTF_LOAD command */
+ emit_sys_bpf(gen, BPF_BTF_LOAD, btf_load_attr, attr_size);
+ debug_ret(gen, "btf_load size %d", btf_raw_size);
+ emit_check_err(gen);
+ /* remember btf_fd in the stack, if successful */
+ emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_7, stack_off(btf_fd)));
+}
+
+void bpf_gen__map_create(struct bpf_gen *gen,
+ enum bpf_map_type map_type,
+ const char *map_name,
+ __u32 key_size, __u32 value_size, __u32 max_entries,
+ struct bpf_map_create_opts *map_attr, int map_idx)
+{
+ int attr_size = offsetofend(union bpf_attr, map_extra);
+ bool close_inner_map_fd = false;
+ int map_create_attr, idx;
+ union bpf_attr attr;
+
+ memset(&attr, 0, attr_size);
+ attr.map_type = map_type;
+ attr.key_size = key_size;
+ attr.value_size = value_size;
+ attr.map_flags = map_attr->map_flags;
+ attr.map_extra = map_attr->map_extra;
+ if (map_name)
+ libbpf_strlcpy(attr.map_name, map_name, sizeof(attr.map_name));
+ attr.numa_node = map_attr->numa_node;
+ attr.map_ifindex = map_attr->map_ifindex;
+ attr.max_entries = max_entries;
+ attr.btf_key_type_id = map_attr->btf_key_type_id;
+ attr.btf_value_type_id = map_attr->btf_value_type_id;
+
+ pr_debug("gen: map_create: %s idx %d type %d value_type_id %d\n",
+ attr.map_name, map_idx, map_type, attr.btf_value_type_id);
+
+ map_create_attr = add_data(gen, &attr, attr_size);
+ if (attr.btf_value_type_id)
+ /* populate union bpf_attr with btf_fd saved in the stack earlier */
+ move_stack2blob(gen, attr_field(map_create_attr, btf_fd), 4,
+ stack_off(btf_fd));
+ switch (attr.map_type) {
+ case BPF_MAP_TYPE_ARRAY_OF_MAPS:
+ case BPF_MAP_TYPE_HASH_OF_MAPS:
+ move_stack2blob(gen, attr_field(map_create_attr, inner_map_fd), 4,
+ stack_off(inner_map_fd));
+ close_inner_map_fd = true;
+ break;
+ default:
+ break;
+ }
+ /* conditionally update max_entries */
+ if (map_idx >= 0)
+ move_ctx2blob(gen, attr_field(map_create_attr, max_entries), 4,
+ sizeof(struct bpf_loader_ctx) +
+ sizeof(struct bpf_map_desc) * map_idx +
+ offsetof(struct bpf_map_desc, max_entries),
+ true /* check that max_entries != 0 */);
+ /* emit MAP_CREATE command */
+ emit_sys_bpf(gen, BPF_MAP_CREATE, map_create_attr, attr_size);
+ debug_ret(gen, "map_create %s idx %d type %d value_size %d value_btf_id %d",
+ attr.map_name, map_idx, map_type, value_size,
+ attr.btf_value_type_id);
+ emit_check_err(gen);
+ /* remember map_fd in the stack, if successful */
+ if (map_idx < 0) {
+ /* This bpf_gen__map_create() function is called with map_idx >= 0
+ * for all maps that libbpf loading logic tracks.
+ * It's called with -1 to create an inner map.
+ */
+ emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_7,
+ stack_off(inner_map_fd)));
+ } else if (map_idx != gen->nr_maps) {
+ gen->error = -EDOM; /* internal bug */
+ return;
+ } else {
+ /* add_map_fd does gen->nr_maps++ */
+ idx = add_map_fd(gen);
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, blob_fd_array_off(gen, idx)));
+ emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_1, BPF_REG_7, 0));
+ }
+ if (close_inner_map_fd)
+ emit_sys_close_stack(gen, stack_off(inner_map_fd));
+}
+
+void bpf_gen__record_attach_target(struct bpf_gen *gen, const char *attach_name,
+ enum bpf_attach_type type)
+{
+ const char *prefix;
+ int kind, ret;
+
+ btf_get_kernel_prefix_kind(type, &prefix, &kind);
+ gen->attach_kind = kind;
+ ret = snprintf(gen->attach_target, sizeof(gen->attach_target), "%s%s",
+ prefix, attach_name);
+ if (ret >= sizeof(gen->attach_target))
+ gen->error = -ENOSPC;
+}
+
+static void emit_find_attach_target(struct bpf_gen *gen)
+{
+ int name, len = strlen(gen->attach_target) + 1;
+
+ pr_debug("gen: find_attach_tgt %s %d\n", gen->attach_target, gen->attach_kind);
+ name = add_data(gen, gen->attach_target, len);
+
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, name));
+ emit(gen, BPF_MOV64_IMM(BPF_REG_2, len));
+ emit(gen, BPF_MOV64_IMM(BPF_REG_3, gen->attach_kind));
+ emit(gen, BPF_MOV64_IMM(BPF_REG_4, 0));
+ emit(gen, BPF_EMIT_CALL(BPF_FUNC_btf_find_by_name_kind));
+ emit(gen, BPF_MOV64_REG(BPF_REG_7, BPF_REG_0));
+ debug_ret(gen, "find_by_name_kind(%s,%d)",
+ gen->attach_target, gen->attach_kind);
+ emit_check_err(gen);
+ /* if successful, btf_id is in lower 32-bit of R7 and
+ * btf_obj_fd is in upper 32-bit
+ */
+}
+
+void bpf_gen__record_extern(struct bpf_gen *gen, const char *name, bool is_weak,
+ bool is_typeless, int kind, int insn_idx)
+{
+ struct ksym_relo_desc *relo;
+
+ relo = libbpf_reallocarray(gen->relos, gen->relo_cnt + 1, sizeof(*relo));
+ if (!relo) {
+ gen->error = -ENOMEM;
+ return;
+ }
+ gen->relos = relo;
+ relo += gen->relo_cnt;
+ relo->name = name;
+ relo->is_weak = is_weak;
+ relo->is_typeless = is_typeless;
+ relo->kind = kind;
+ relo->insn_idx = insn_idx;
+ gen->relo_cnt++;
+}
+
+/* returns existing ksym_desc with ref incremented, or inserts a new one */
+static struct ksym_desc *get_ksym_desc(struct bpf_gen *gen, struct ksym_relo_desc *relo)
+{
+ struct ksym_desc *kdesc;
+ int i;
+
+ for (i = 0; i < gen->nr_ksyms; i++) {
+ if (!strcmp(gen->ksyms[i].name, relo->name)) {
+ gen->ksyms[i].ref++;
+ return &gen->ksyms[i];
+ }
+ }
+ kdesc = libbpf_reallocarray(gen->ksyms, gen->nr_ksyms + 1, sizeof(*kdesc));
+ if (!kdesc) {
+ gen->error = -ENOMEM;
+ return NULL;
+ }
+ gen->ksyms = kdesc;
+ kdesc = &gen->ksyms[gen->nr_ksyms++];
+ kdesc->name = relo->name;
+ kdesc->kind = relo->kind;
+ kdesc->ref = 1;
+ kdesc->off = 0;
+ kdesc->insn = 0;
+ return kdesc;
+}
+
+/* Overwrites BPF_REG_{0, 1, 2, 3, 4, 7}
+ * Returns result in BPF_REG_7
+ */
+static void emit_bpf_find_by_name_kind(struct bpf_gen *gen, struct ksym_relo_desc *relo)
+{
+ int name_off, len = strlen(relo->name) + 1;
+
+ name_off = add_data(gen, relo->name, len);
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, name_off));
+ emit(gen, BPF_MOV64_IMM(BPF_REG_2, len));
+ emit(gen, BPF_MOV64_IMM(BPF_REG_3, relo->kind));
+ emit(gen, BPF_MOV64_IMM(BPF_REG_4, 0));
+ emit(gen, BPF_EMIT_CALL(BPF_FUNC_btf_find_by_name_kind));
+ emit(gen, BPF_MOV64_REG(BPF_REG_7, BPF_REG_0));
+ debug_ret(gen, "find_by_name_kind(%s,%d)", relo->name, relo->kind);
+}
+
+/* Overwrites BPF_REG_{0, 1, 2, 3, 4, 7}
+ * Returns result in BPF_REG_7
+ * Returns u64 symbol addr in BPF_REG_9
+ */
+static void emit_bpf_kallsyms_lookup_name(struct bpf_gen *gen, struct ksym_relo_desc *relo)
+{
+ int name_off, len = strlen(relo->name) + 1, res_off;
+
+ name_off = add_data(gen, relo->name, len);
+ res_off = add_data(gen, NULL, 8); /* res is u64 */
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, name_off));
+ emit(gen, BPF_MOV64_IMM(BPF_REG_2, len));
+ emit(gen, BPF_MOV64_IMM(BPF_REG_3, 0));
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_4, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, res_off));
+ emit(gen, BPF_MOV64_REG(BPF_REG_7, BPF_REG_4));
+ emit(gen, BPF_EMIT_CALL(BPF_FUNC_kallsyms_lookup_name));
+ emit(gen, BPF_LDX_MEM(BPF_DW, BPF_REG_9, BPF_REG_7, 0));
+ emit(gen, BPF_MOV64_REG(BPF_REG_7, BPF_REG_0));
+ debug_ret(gen, "kallsyms_lookup_name(%s,%d)", relo->name, relo->kind);
+}
+
+/* Expects:
+ * BPF_REG_8 - pointer to instruction
+ *
+ * We need to reuse BTF fd for same symbol otherwise each relocation takes a new
+ * index, while kernel limits total kfunc BTFs to 256. For duplicate symbols,
+ * this would mean a new BTF fd index for each entry. By pairing symbol name
+ * with index, we get the insn->imm, insn->off pairing that kernel uses for
+ * kfunc_tab, which becomes the effective limit even though all of them may
+ * share same index in fd_array (such that kfunc_btf_tab has 1 element).
+ */
+static void emit_relo_kfunc_btf(struct bpf_gen *gen, struct ksym_relo_desc *relo, int insn)
+{
+ struct ksym_desc *kdesc;
+ int btf_fd_idx;
+
+ kdesc = get_ksym_desc(gen, relo);
+ if (!kdesc)
+ return;
+ /* try to copy from existing bpf_insn */
+ if (kdesc->ref > 1) {
+ move_blob2blob(gen, insn + offsetof(struct bpf_insn, imm), 4,
+ kdesc->insn + offsetof(struct bpf_insn, imm));
+ move_blob2blob(gen, insn + offsetof(struct bpf_insn, off), 2,
+ kdesc->insn + offsetof(struct bpf_insn, off));
+ goto log;
+ }
+ /* remember insn offset, so we can copy BTF ID and FD later */
+ kdesc->insn = insn;
+ emit_bpf_find_by_name_kind(gen, relo);
+ if (!relo->is_weak)
+ emit_check_err(gen);
+ /* get index in fd_array to store BTF FD at */
+ btf_fd_idx = add_kfunc_btf_fd(gen);
+ if (btf_fd_idx > INT16_MAX) {
+ pr_warn("BTF fd off %d for kfunc %s exceeds INT16_MAX, cannot process relocation\n",
+ btf_fd_idx, relo->name);
+ gen->error = -E2BIG;
+ return;
+ }
+ kdesc->off = btf_fd_idx;
+ /* jump to success case */
+ emit(gen, BPF_JMP_IMM(BPF_JSGE, BPF_REG_7, 0, 3));
+ /* set value for imm, off as 0 */
+ emit(gen, BPF_ST_MEM(BPF_W, BPF_REG_8, offsetof(struct bpf_insn, imm), 0));
+ emit(gen, BPF_ST_MEM(BPF_H, BPF_REG_8, offsetof(struct bpf_insn, off), 0));
+ /* skip success case for ret < 0 */
+ emit(gen, BPF_JMP_IMM(BPF_JA, 0, 0, 10));
+ /* store btf_id into insn[insn_idx].imm */
+ emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_8, BPF_REG_7, offsetof(struct bpf_insn, imm)));
+ /* obtain fd in BPF_REG_9 */
+ emit(gen, BPF_MOV64_REG(BPF_REG_9, BPF_REG_7));
+ emit(gen, BPF_ALU64_IMM(BPF_RSH, BPF_REG_9, 32));
+ /* jump to fd_array store if fd denotes module BTF */
+ emit(gen, BPF_JMP_IMM(BPF_JNE, BPF_REG_9, 0, 2));
+ /* set the default value for off */
+ emit(gen, BPF_ST_MEM(BPF_H, BPF_REG_8, offsetof(struct bpf_insn, off), 0));
+ /* skip BTF fd store for vmlinux BTF */
+ emit(gen, BPF_JMP_IMM(BPF_JA, 0, 0, 4));
+ /* load fd_array slot pointer */
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_0, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, blob_fd_array_off(gen, btf_fd_idx)));
+ /* store BTF fd in slot */
+ emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_0, BPF_REG_9, 0));
+ /* store index into insn[insn_idx].off */
+ emit(gen, BPF_ST_MEM(BPF_H, BPF_REG_8, offsetof(struct bpf_insn, off), btf_fd_idx));
+log:
+ if (!gen->log_level)
+ return;
+ emit(gen, BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_8,
+ offsetof(struct bpf_insn, imm)));
+ emit(gen, BPF_LDX_MEM(BPF_H, BPF_REG_9, BPF_REG_8,
+ offsetof(struct bpf_insn, off)));
+ debug_regs(gen, BPF_REG_7, BPF_REG_9, " func (%s:count=%d): imm: %%d, off: %%d",
+ relo->name, kdesc->ref);
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_0, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, blob_fd_array_off(gen, kdesc->off)));
+ emit(gen, BPF_LDX_MEM(BPF_W, BPF_REG_9, BPF_REG_0, 0));
+ debug_regs(gen, BPF_REG_9, -1, " func (%s:count=%d): btf_fd",
+ relo->name, kdesc->ref);
+}
+
+static void emit_ksym_relo_log(struct bpf_gen *gen, struct ksym_relo_desc *relo,
+ int ref)
+{
+ if (!gen->log_level)
+ return;
+ emit(gen, BPF_LDX_MEM(BPF_W, BPF_REG_7, BPF_REG_8,
+ offsetof(struct bpf_insn, imm)));
+ emit(gen, BPF_LDX_MEM(BPF_H, BPF_REG_9, BPF_REG_8, sizeof(struct bpf_insn) +
+ offsetof(struct bpf_insn, imm)));
+ debug_regs(gen, BPF_REG_7, BPF_REG_9, " var t=%d w=%d (%s:count=%d): imm[0]: %%d, imm[1]: %%d",
+ relo->is_typeless, relo->is_weak, relo->name, ref);
+ emit(gen, BPF_LDX_MEM(BPF_B, BPF_REG_9, BPF_REG_8, offsetofend(struct bpf_insn, code)));
+ debug_regs(gen, BPF_REG_9, -1, " var t=%d w=%d (%s:count=%d): insn.reg",
+ relo->is_typeless, relo->is_weak, relo->name, ref);
+}
+
+/* Expects:
+ * BPF_REG_8 - pointer to instruction
+ */
+static void emit_relo_ksym_typeless(struct bpf_gen *gen,
+ struct ksym_relo_desc *relo, int insn)
+{
+ struct ksym_desc *kdesc;
+
+ kdesc = get_ksym_desc(gen, relo);
+ if (!kdesc)
+ return;
+ /* try to copy from existing ldimm64 insn */
+ if (kdesc->ref > 1) {
+ move_blob2blob(gen, insn + offsetof(struct bpf_insn, imm), 4,
+ kdesc->insn + offsetof(struct bpf_insn, imm));
+ move_blob2blob(gen, insn + sizeof(struct bpf_insn) + offsetof(struct bpf_insn, imm), 4,
+ kdesc->insn + sizeof(struct bpf_insn) + offsetof(struct bpf_insn, imm));
+ goto log;
+ }
+ /* remember insn offset, so we can copy ksym addr later */
+ kdesc->insn = insn;
+ /* skip typeless ksym_desc in fd closing loop in cleanup_relos */
+ kdesc->typeless = true;
+ emit_bpf_kallsyms_lookup_name(gen, relo);
+ emit(gen, BPF_JMP_IMM(BPF_JEQ, BPF_REG_7, -ENOENT, 1));
+ emit_check_err(gen);
+ /* store lower half of addr into insn[insn_idx].imm */
+ emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_8, BPF_REG_9, offsetof(struct bpf_insn, imm)));
+ /* store upper half of addr into insn[insn_idx + 1].imm */
+ emit(gen, BPF_ALU64_IMM(BPF_RSH, BPF_REG_9, 32));
+ emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_8, BPF_REG_9,
+ sizeof(struct bpf_insn) + offsetof(struct bpf_insn, imm)));
+log:
+ emit_ksym_relo_log(gen, relo, kdesc->ref);
+}
+
+static __u32 src_reg_mask(void)
+{
+#if defined(__LITTLE_ENDIAN_BITFIELD)
+ return 0x0f; /* src_reg,dst_reg,... */
+#elif defined(__BIG_ENDIAN_BITFIELD)
+ return 0xf0; /* dst_reg,src_reg,... */
+#else
+#error "Unsupported bit endianness, cannot proceed"
+#endif
+}
+
+/* Expects:
+ * BPF_REG_8 - pointer to instruction
+ */
+static void emit_relo_ksym_btf(struct bpf_gen *gen, struct ksym_relo_desc *relo, int insn)
+{
+ struct ksym_desc *kdesc;
+ __u32 reg_mask;
+
+ kdesc = get_ksym_desc(gen, relo);
+ if (!kdesc)
+ return;
+ /* try to copy from existing ldimm64 insn */
+ if (kdesc->ref > 1) {
+ move_blob2blob(gen, insn + offsetof(struct bpf_insn, imm), 4,
+ kdesc->insn + offsetof(struct bpf_insn, imm));
+ move_blob2blob(gen, insn + sizeof(struct bpf_insn) + offsetof(struct bpf_insn, imm), 4,
+ kdesc->insn + sizeof(struct bpf_insn) + offsetof(struct bpf_insn, imm));
+ /* jump over src_reg adjustment if imm is not 0, reuse BPF_REG_0 from move_blob2blob */
+ emit(gen, BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 3));
+ goto clear_src_reg;
+ }
+ /* remember insn offset, so we can copy BTF ID and FD later */
+ kdesc->insn = insn;
+ emit_bpf_find_by_name_kind(gen, relo);
+ if (!relo->is_weak)
+ emit_check_err(gen);
+ /* jump to success case */
+ emit(gen, BPF_JMP_IMM(BPF_JSGE, BPF_REG_7, 0, 3));
+ /* set values for insn[insn_idx].imm, insn[insn_idx + 1].imm as 0 */
+ emit(gen, BPF_ST_MEM(BPF_W, BPF_REG_8, offsetof(struct bpf_insn, imm), 0));
+ emit(gen, BPF_ST_MEM(BPF_W, BPF_REG_8, sizeof(struct bpf_insn) + offsetof(struct bpf_insn, imm), 0));
+ /* skip success case for ret < 0 */
+ emit(gen, BPF_JMP_IMM(BPF_JA, 0, 0, 4));
+ /* store btf_id into insn[insn_idx].imm */
+ emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_8, BPF_REG_7, offsetof(struct bpf_insn, imm)));
+ /* store btf_obj_fd into insn[insn_idx + 1].imm */
+ emit(gen, BPF_ALU64_IMM(BPF_RSH, BPF_REG_7, 32));
+ emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_8, BPF_REG_7,
+ sizeof(struct bpf_insn) + offsetof(struct bpf_insn, imm)));
+ /* skip src_reg adjustment */
+ emit(gen, BPF_JMP_IMM(BPF_JSGE, BPF_REG_7, 0, 3));
+clear_src_reg:
+ /* clear bpf_object__relocate_data's src_reg assignment, otherwise we get a verifier failure */
+ reg_mask = src_reg_mask();
+ emit(gen, BPF_LDX_MEM(BPF_B, BPF_REG_9, BPF_REG_8, offsetofend(struct bpf_insn, code)));
+ emit(gen, BPF_ALU32_IMM(BPF_AND, BPF_REG_9, reg_mask));
+ emit(gen, BPF_STX_MEM(BPF_B, BPF_REG_8, BPF_REG_9, offsetofend(struct bpf_insn, code)));
+
+ emit_ksym_relo_log(gen, relo, kdesc->ref);
+}
+
+void bpf_gen__record_relo_core(struct bpf_gen *gen,
+ const struct bpf_core_relo *core_relo)
+{
+ struct bpf_core_relo *relos;
+
+ relos = libbpf_reallocarray(gen->core_relos, gen->core_relo_cnt + 1, sizeof(*relos));
+ if (!relos) {
+ gen->error = -ENOMEM;
+ return;
+ }
+ gen->core_relos = relos;
+ relos += gen->core_relo_cnt;
+ memcpy(relos, core_relo, sizeof(*relos));
+ gen->core_relo_cnt++;
+}
+
+static void emit_relo(struct bpf_gen *gen, struct ksym_relo_desc *relo, int insns)
+{
+ int insn;
+
+ pr_debug("gen: emit_relo (%d): %s at %d\n", relo->kind, relo->name, relo->insn_idx);
+ insn = insns + sizeof(struct bpf_insn) * relo->insn_idx;
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_8, BPF_PSEUDO_MAP_IDX_VALUE, 0, 0, 0, insn));
+ switch (relo->kind) {
+ case BTF_KIND_VAR:
+ if (relo->is_typeless)
+ emit_relo_ksym_typeless(gen, relo, insn);
+ else
+ emit_relo_ksym_btf(gen, relo, insn);
+ break;
+ case BTF_KIND_FUNC:
+ emit_relo_kfunc_btf(gen, relo, insn);
+ break;
+ default:
+ pr_warn("Unknown relocation kind '%d'\n", relo->kind);
+ gen->error = -EDOM;
+ return;
+ }
+}
+
+static void emit_relos(struct bpf_gen *gen, int insns)
+{
+ int i;
+
+ for (i = 0; i < gen->relo_cnt; i++)
+ emit_relo(gen, gen->relos + i, insns);
+}
+
+static void cleanup_core_relo(struct bpf_gen *gen)
+{
+ if (!gen->core_relo_cnt)
+ return;
+ free(gen->core_relos);
+ gen->core_relo_cnt = 0;
+ gen->core_relos = NULL;
+}
+
+static void cleanup_relos(struct bpf_gen *gen, int insns)
+{
+ int i, insn;
+
+ for (i = 0; i < gen->nr_ksyms; i++) {
+ /* only close fds for typed ksyms and kfuncs */
+ if (gen->ksyms[i].kind == BTF_KIND_VAR && !gen->ksyms[i].typeless) {
+ /* close fd recorded in insn[insn_idx + 1].imm */
+ insn = gen->ksyms[i].insn;
+ insn += sizeof(struct bpf_insn) + offsetof(struct bpf_insn, imm);
+ emit_sys_close_blob(gen, insn);
+ } else if (gen->ksyms[i].kind == BTF_KIND_FUNC) {
+ emit_sys_close_blob(gen, blob_fd_array_off(gen, gen->ksyms[i].off));
+ if (gen->ksyms[i].off < MAX_FD_ARRAY_SZ)
+ gen->nr_fd_array--;
+ }
+ }
+ if (gen->nr_ksyms) {
+ free(gen->ksyms);
+ gen->nr_ksyms = 0;
+ gen->ksyms = NULL;
+ }
+ if (gen->relo_cnt) {
+ free(gen->relos);
+ gen->relo_cnt = 0;
+ gen->relos = NULL;
+ }
+ cleanup_core_relo(gen);
+}
+
+void bpf_gen__prog_load(struct bpf_gen *gen,
+ enum bpf_prog_type prog_type, const char *prog_name,
+ const char *license, struct bpf_insn *insns, size_t insn_cnt,
+ struct bpf_prog_load_opts *load_attr, int prog_idx)
+{
+ int prog_load_attr, license_off, insns_off, func_info, line_info, core_relos;
+ int attr_size = offsetofend(union bpf_attr, core_relo_rec_size);
+ union bpf_attr attr;
+
+ memset(&attr, 0, attr_size);
+ pr_debug("gen: prog_load: type %d insns_cnt %zd progi_idx %d\n",
+ prog_type, insn_cnt, prog_idx);
+ /* add license string to blob of bytes */
+ license_off = add_data(gen, license, strlen(license) + 1);
+ /* add insns to blob of bytes */
+ insns_off = add_data(gen, insns, insn_cnt * sizeof(struct bpf_insn));
+
+ attr.prog_type = prog_type;
+ attr.expected_attach_type = load_attr->expected_attach_type;
+ attr.attach_btf_id = load_attr->attach_btf_id;
+ attr.prog_ifindex = load_attr->prog_ifindex;
+ attr.kern_version = 0;
+ attr.insn_cnt = (__u32)insn_cnt;
+ attr.prog_flags = load_attr->prog_flags;
+
+ attr.func_info_rec_size = load_attr->func_info_rec_size;
+ attr.func_info_cnt = load_attr->func_info_cnt;
+ func_info = add_data(gen, load_attr->func_info,
+ attr.func_info_cnt * attr.func_info_rec_size);
+
+ attr.line_info_rec_size = load_attr->line_info_rec_size;
+ attr.line_info_cnt = load_attr->line_info_cnt;
+ line_info = add_data(gen, load_attr->line_info,
+ attr.line_info_cnt * attr.line_info_rec_size);
+
+ attr.core_relo_rec_size = sizeof(struct bpf_core_relo);
+ attr.core_relo_cnt = gen->core_relo_cnt;
+ core_relos = add_data(gen, gen->core_relos,
+ attr.core_relo_cnt * attr.core_relo_rec_size);
+
+ libbpf_strlcpy(attr.prog_name, prog_name, sizeof(attr.prog_name));
+ prog_load_attr = add_data(gen, &attr, attr_size);
+
+ /* populate union bpf_attr with a pointer to license */
+ emit_rel_store(gen, attr_field(prog_load_attr, license), license_off);
+
+ /* populate union bpf_attr with a pointer to instructions */
+ emit_rel_store(gen, attr_field(prog_load_attr, insns), insns_off);
+
+ /* populate union bpf_attr with a pointer to func_info */
+ emit_rel_store(gen, attr_field(prog_load_attr, func_info), func_info);
+
+ /* populate union bpf_attr with a pointer to line_info */
+ emit_rel_store(gen, attr_field(prog_load_attr, line_info), line_info);
+
+ /* populate union bpf_attr with a pointer to core_relos */
+ emit_rel_store(gen, attr_field(prog_load_attr, core_relos), core_relos);
+
+ /* populate union bpf_attr fd_array with a pointer to data where map_fds are saved */
+ emit_rel_store(gen, attr_field(prog_load_attr, fd_array), gen->fd_array);
+
+ /* populate union bpf_attr with user provided log details */
+ move_ctx2blob(gen, attr_field(prog_load_attr, log_level), 4,
+ offsetof(struct bpf_loader_ctx, log_level), false);
+ move_ctx2blob(gen, attr_field(prog_load_attr, log_size), 4,
+ offsetof(struct bpf_loader_ctx, log_size), false);
+ move_ctx2blob(gen, attr_field(prog_load_attr, log_buf), 8,
+ offsetof(struct bpf_loader_ctx, log_buf), false);
+ /* populate union bpf_attr with btf_fd saved in the stack earlier */
+ move_stack2blob(gen, attr_field(prog_load_attr, prog_btf_fd), 4,
+ stack_off(btf_fd));
+ if (gen->attach_kind) {
+ emit_find_attach_target(gen);
+ /* populate union bpf_attr with btf_id and btf_obj_fd found by helper */
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_0, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, prog_load_attr));
+ emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_0, BPF_REG_7,
+ offsetof(union bpf_attr, attach_btf_id)));
+ emit(gen, BPF_ALU64_IMM(BPF_RSH, BPF_REG_7, 32));
+ emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_0, BPF_REG_7,
+ offsetof(union bpf_attr, attach_btf_obj_fd)));
+ }
+ emit_relos(gen, insns_off);
+ /* emit PROG_LOAD command */
+ emit_sys_bpf(gen, BPF_PROG_LOAD, prog_load_attr, attr_size);
+ debug_ret(gen, "prog_load %s insn_cnt %d", attr.prog_name, attr.insn_cnt);
+ /* successful or not, close btf module FDs used in extern ksyms and attach_btf_obj_fd */
+ cleanup_relos(gen, insns_off);
+ if (gen->attach_kind) {
+ emit_sys_close_blob(gen,
+ attr_field(prog_load_attr, attach_btf_obj_fd));
+ gen->attach_kind = 0;
+ }
+ emit_check_err(gen);
+ /* remember prog_fd in the stack, if successful */
+ emit(gen, BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_7,
+ stack_off(prog_fd[gen->nr_progs])));
+ gen->nr_progs++;
+}
+
+void bpf_gen__map_update_elem(struct bpf_gen *gen, int map_idx, void *pvalue,
+ __u32 value_size)
+{
+ int attr_size = offsetofend(union bpf_attr, flags);
+ int map_update_attr, value, key;
+ union bpf_attr attr;
+ int zero = 0;
+
+ memset(&attr, 0, attr_size);
+ pr_debug("gen: map_update_elem: idx %d\n", map_idx);
+
+ value = add_data(gen, pvalue, value_size);
+ key = add_data(gen, &zero, sizeof(zero));
+
+ /* if (map_desc[map_idx].initial_value) {
+ * if (ctx->flags & BPF_SKEL_KERNEL)
+ * bpf_probe_read_kernel(value, value_size, initial_value);
+ * else
+ * bpf_copy_from_user(value, value_size, initial_value);
+ * }
+ */
+ emit(gen, BPF_LDX_MEM(BPF_DW, BPF_REG_3, BPF_REG_6,
+ sizeof(struct bpf_loader_ctx) +
+ sizeof(struct bpf_map_desc) * map_idx +
+ offsetof(struct bpf_map_desc, initial_value)));
+ emit(gen, BPF_JMP_IMM(BPF_JEQ, BPF_REG_3, 0, 8));
+ emit2(gen, BPF_LD_IMM64_RAW_FULL(BPF_REG_1, BPF_PSEUDO_MAP_IDX_VALUE,
+ 0, 0, 0, value));
+ emit(gen, BPF_MOV64_IMM(BPF_REG_2, value_size));
+ emit(gen, BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_6,
+ offsetof(struct bpf_loader_ctx, flags)));
+ emit(gen, BPF_JMP_IMM(BPF_JSET, BPF_REG_0, BPF_SKEL_KERNEL, 2));
+ emit(gen, BPF_EMIT_CALL(BPF_FUNC_copy_from_user));
+ emit(gen, BPF_JMP_IMM(BPF_JA, 0, 0, 1));
+ emit(gen, BPF_EMIT_CALL(BPF_FUNC_probe_read_kernel));
+
+ map_update_attr = add_data(gen, &attr, attr_size);
+ move_blob2blob(gen, attr_field(map_update_attr, map_fd), 4,
+ blob_fd_array_off(gen, map_idx));
+ emit_rel_store(gen, attr_field(map_update_attr, key), key);
+ emit_rel_store(gen, attr_field(map_update_attr, value), value);
+ /* emit MAP_UPDATE_ELEM command */
+ emit_sys_bpf(gen, BPF_MAP_UPDATE_ELEM, map_update_attr, attr_size);
+ debug_ret(gen, "update_elem idx %d value_size %d", map_idx, value_size);
+ emit_check_err(gen);
+}
+
+void bpf_gen__populate_outer_map(struct bpf_gen *gen, int outer_map_idx, int slot,
+ int inner_map_idx)
+{
+ int attr_size = offsetofend(union bpf_attr, flags);
+ int map_update_attr, key;
+ union bpf_attr attr;
+
+ memset(&attr, 0, attr_size);
+ pr_debug("gen: populate_outer_map: outer %d key %d inner %d\n",
+ outer_map_idx, slot, inner_map_idx);
+
+ key = add_data(gen, &slot, sizeof(slot));
+
+ map_update_attr = add_data(gen, &attr, attr_size);
+ move_blob2blob(gen, attr_field(map_update_attr, map_fd), 4,
+ blob_fd_array_off(gen, outer_map_idx));
+ emit_rel_store(gen, attr_field(map_update_attr, key), key);
+ emit_rel_store(gen, attr_field(map_update_attr, value),
+ blob_fd_array_off(gen, inner_map_idx));
+
+ /* emit MAP_UPDATE_ELEM command */
+ emit_sys_bpf(gen, BPF_MAP_UPDATE_ELEM, map_update_attr, attr_size);
+ debug_ret(gen, "populate_outer_map outer %d key %d inner %d",
+ outer_map_idx, slot, inner_map_idx);
+ emit_check_err(gen);
+}
+
+void bpf_gen__map_freeze(struct bpf_gen *gen, int map_idx)
+{
+ int attr_size = offsetofend(union bpf_attr, map_fd);
+ int map_freeze_attr;
+ union bpf_attr attr;
+
+ memset(&attr, 0, attr_size);
+ pr_debug("gen: map_freeze: idx %d\n", map_idx);
+ map_freeze_attr = add_data(gen, &attr, attr_size);
+ move_blob2blob(gen, attr_field(map_freeze_attr, map_fd), 4,
+ blob_fd_array_off(gen, map_idx));
+ /* emit MAP_FREEZE command */
+ emit_sys_bpf(gen, BPF_MAP_FREEZE, map_freeze_attr, attr_size);
+ debug_ret(gen, "map_freeze");
+ emit_check_err(gen);
+}