summaryrefslogtreecommitdiff
path: root/tools/lib/bpf/gen_loader.c
diff options
context:
space:
mode:
authorJakub Kicinski <kuba@kernel.org>2021-11-19 00:13:16 +0300
committerJakub Kicinski <kuba@kernel.org>2021-11-19 00:13:16 +0300
commit50fc24944a2a0ef5aab571dcac17f6c5f2613f56 (patch)
tree32477b48cc10073e948eb7b85877dc5a0746749d /tools/lib/bpf/gen_loader.c
parentbb8cecf8ba127abca8ccd102207a59c55fdae515 (diff)
parent8d0112ac6fd001f95aabb084ec2ccaa3637bc344 (diff)
downloadlinux-50fc24944a2a0ef5aab571dcac17f6c5f2613f56.tar.xz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'tools/lib/bpf/gen_loader.c')
-rw-r--r--tools/lib/bpf/gen_loader.c47
1 files changed, 30 insertions, 17 deletions
diff --git a/tools/lib/bpf/gen_loader.c b/tools/lib/bpf/gen_loader.c
index 7b73f97b1fa1..c28ab24d1bff 100644
--- a/tools/lib/bpf/gen_loader.c
+++ b/tools/lib/bpf/gen_loader.c
@@ -18,7 +18,7 @@
#define MAX_USED_MAPS 64
#define MAX_USED_PROGS 32
#define MAX_KFUNC_DESCS 256
-#define MAX_FD_ARRAY_SZ (MAX_USED_PROGS + MAX_KFUNC_DESCS)
+#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.
@@ -33,8 +33,8 @@
*/
struct loader_stack {
__u32 btf_fd;
- __u32 prog_fd[MAX_USED_PROGS];
__u32 inner_map_fd;
+ __u32 prog_fd[MAX_USED_PROGS];
};
#define stack_off(field) \
@@ -42,6 +42,11 @@ struct loader_stack {
#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;
@@ -102,11 +107,15 @@ static void emit2(struct bpf_gen *gen, struct bpf_insn insn1, struct bpf_insn in
emit(gen, insn2);
}
-void bpf_gen__init(struct bpf_gen *gen, int log_level)
+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);
+ 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));
@@ -118,19 +127,27 @@ void bpf_gen__init(struct bpf_gen *gen, int log_level)
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 */
- (stack_sz / 4) * 3 + 2));
+ /* 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 < stack_sz; i += 4) {
+ 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());
@@ -160,8 +177,6 @@ static int add_data(struct bpf_gen *gen, const void *data, __u32 size)
*/
static int add_map_fd(struct bpf_gen *gen)
{
- if (!gen->fd_array)
- gen->fd_array = add_data(gen, NULL, MAX_FD_ARRAY_SZ * sizeof(int));
if (gen->nr_maps == MAX_USED_MAPS) {
pr_warn("Total maps exceeds %d\n", MAX_USED_MAPS);
gen->error = -E2BIG;
@@ -174,8 +189,6 @@ static int add_kfunc_btf_fd(struct bpf_gen *gen)
{
int cur;
- if (!gen->fd_array)
- gen->fd_array = add_data(gen, NULL, MAX_FD_ARRAY_SZ * sizeof(int));
if (gen->nr_fd_array == MAX_KFUNC_DESCS) {
cur = add_data(gen, NULL, sizeof(int));
return (cur - gen->fd_array) / sizeof(int);
@@ -183,11 +196,6 @@ static int add_kfunc_btf_fd(struct bpf_gen *gen)
return MAX_USED_MAPS + gen->nr_fd_array++;
}
-static int blob_fd_array_off(struct bpf_gen *gen, int index)
-{
- return gen->fd_array + index * sizeof(int);
-}
-
static int insn_bytes_to_bpf_size(__u32 sz)
{
switch (sz) {
@@ -359,10 +367,15 @@ static void emit_sys_close_blob(struct bpf_gen *gen, int blob_off)
__emit_sys_close(gen);
}
-int bpf_gen__finish(struct bpf_gen *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("progs/maps mismatch\n");
+ 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,