v4.19.13 snapshot.
diff --git a/drivers/media/rc/bpf-lirc.c b/drivers/media/rc/bpf-lirc.c
new file mode 100644
index 0000000..8b97fd1
--- /dev/null
+++ b/drivers/media/rc/bpf-lirc.c
@@ -0,0 +1,306 @@
+// SPDX-License-Identifier: GPL-2.0
+// bpf-lirc.c - handles bpf
+//
+// Copyright (C) 2018 Sean Young <sean@mess.org>
+
+#include <linux/bpf.h>
+#include <linux/filter.h>
+#include <linux/bpf_lirc.h>
+#include "rc-core-priv.h"
+
+/*
+ * BPF interface for raw IR
+ */
+const struct bpf_prog_ops lirc_mode2_prog_ops = {
+};
+
+BPF_CALL_1(bpf_rc_repeat, u32*, sample)
+{
+ struct ir_raw_event_ctrl *ctrl;
+
+ ctrl = container_of(sample, struct ir_raw_event_ctrl, bpf_sample);
+
+ rc_repeat(ctrl->dev);
+
+ return 0;
+}
+
+static const struct bpf_func_proto rc_repeat_proto = {
+ .func = bpf_rc_repeat,
+ .gpl_only = true, /* rc_repeat is EXPORT_SYMBOL_GPL */
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+};
+
+/*
+ * Currently rc-core does not support 64-bit scancodes, but there are many
+ * known protocols with more than 32 bits. So, define the interface as u64
+ * as a future-proof.
+ */
+BPF_CALL_4(bpf_rc_keydown, u32*, sample, u32, protocol, u64, scancode,
+ u32, toggle)
+{
+ struct ir_raw_event_ctrl *ctrl;
+
+ ctrl = container_of(sample, struct ir_raw_event_ctrl, bpf_sample);
+
+ rc_keydown(ctrl->dev, protocol, scancode, toggle != 0);
+
+ return 0;
+}
+
+static const struct bpf_func_proto rc_keydown_proto = {
+ .func = bpf_rc_keydown,
+ .gpl_only = true, /* rc_keydown is EXPORT_SYMBOL_GPL */
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_ANYTHING,
+ .arg3_type = ARG_ANYTHING,
+ .arg4_type = ARG_ANYTHING,
+};
+
+static const struct bpf_func_proto *
+lirc_mode2_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
+{
+ switch (func_id) {
+ case BPF_FUNC_rc_repeat:
+ return &rc_repeat_proto;
+ case BPF_FUNC_rc_keydown:
+ return &rc_keydown_proto;
+ case BPF_FUNC_map_lookup_elem:
+ return &bpf_map_lookup_elem_proto;
+ case BPF_FUNC_map_update_elem:
+ return &bpf_map_update_elem_proto;
+ case BPF_FUNC_map_delete_elem:
+ return &bpf_map_delete_elem_proto;
+ case BPF_FUNC_ktime_get_ns:
+ return &bpf_ktime_get_ns_proto;
+ case BPF_FUNC_tail_call:
+ return &bpf_tail_call_proto;
+ case BPF_FUNC_get_prandom_u32:
+ return &bpf_get_prandom_u32_proto;
+ case BPF_FUNC_trace_printk:
+ if (capable(CAP_SYS_ADMIN))
+ return bpf_get_trace_printk_proto();
+ /* fall through */
+ default:
+ return NULL;
+ }
+}
+
+static bool lirc_mode2_is_valid_access(int off, int size,
+ enum bpf_access_type type,
+ const struct bpf_prog *prog,
+ struct bpf_insn_access_aux *info)
+{
+ /* We have one field of u32 */
+ return type == BPF_READ && off == 0 && size == sizeof(u32);
+}
+
+const struct bpf_verifier_ops lirc_mode2_verifier_ops = {
+ .get_func_proto = lirc_mode2_func_proto,
+ .is_valid_access = lirc_mode2_is_valid_access
+};
+
+#define BPF_MAX_PROGS 64
+
+static int lirc_bpf_attach(struct rc_dev *rcdev, struct bpf_prog *prog)
+{
+ struct bpf_prog_array __rcu *old_array;
+ struct bpf_prog_array *new_array;
+ struct ir_raw_event_ctrl *raw;
+ int ret;
+
+ if (rcdev->driver_type != RC_DRIVER_IR_RAW)
+ return -EINVAL;
+
+ ret = mutex_lock_interruptible(&ir_raw_handler_lock);
+ if (ret)
+ return ret;
+
+ raw = rcdev->raw;
+ if (!raw) {
+ ret = -ENODEV;
+ goto unlock;
+ }
+
+ if (raw->progs && bpf_prog_array_length(raw->progs) >= BPF_MAX_PROGS) {
+ ret = -E2BIG;
+ goto unlock;
+ }
+
+ old_array = raw->progs;
+ ret = bpf_prog_array_copy(old_array, NULL, prog, &new_array);
+ if (ret < 0)
+ goto unlock;
+
+ rcu_assign_pointer(raw->progs, new_array);
+ bpf_prog_array_free(old_array);
+
+unlock:
+ mutex_unlock(&ir_raw_handler_lock);
+ return ret;
+}
+
+static int lirc_bpf_detach(struct rc_dev *rcdev, struct bpf_prog *prog)
+{
+ struct bpf_prog_array __rcu *old_array;
+ struct bpf_prog_array *new_array;
+ struct ir_raw_event_ctrl *raw;
+ int ret;
+
+ if (rcdev->driver_type != RC_DRIVER_IR_RAW)
+ return -EINVAL;
+
+ ret = mutex_lock_interruptible(&ir_raw_handler_lock);
+ if (ret)
+ return ret;
+
+ raw = rcdev->raw;
+ if (!raw) {
+ ret = -ENODEV;
+ goto unlock;
+ }
+
+ old_array = raw->progs;
+ ret = bpf_prog_array_copy(old_array, prog, NULL, &new_array);
+ /*
+ * Do not use bpf_prog_array_delete_safe() as we would end up
+ * with a dummy entry in the array, and the we would free the
+ * dummy in lirc_bpf_free()
+ */
+ if (ret)
+ goto unlock;
+
+ rcu_assign_pointer(raw->progs, new_array);
+ bpf_prog_array_free(old_array);
+ bpf_prog_put(prog);
+unlock:
+ mutex_unlock(&ir_raw_handler_lock);
+ return ret;
+}
+
+void lirc_bpf_run(struct rc_dev *rcdev, u32 sample)
+{
+ struct ir_raw_event_ctrl *raw = rcdev->raw;
+
+ raw->bpf_sample = sample;
+
+ if (raw->progs)
+ BPF_PROG_RUN_ARRAY(raw->progs, &raw->bpf_sample, BPF_PROG_RUN);
+}
+
+/*
+ * This should be called once the rc thread has been stopped, so there can be
+ * no concurrent bpf execution.
+ */
+void lirc_bpf_free(struct rc_dev *rcdev)
+{
+ struct bpf_prog_array_item *item;
+
+ if (!rcdev->raw->progs)
+ return;
+
+ item = rcu_dereference(rcdev->raw->progs)->items;
+ while (item->prog) {
+ bpf_prog_put(item->prog);
+ item++;
+ }
+
+ bpf_prog_array_free(rcdev->raw->progs);
+}
+
+int lirc_prog_attach(const union bpf_attr *attr, struct bpf_prog *prog)
+{
+ struct rc_dev *rcdev;
+ int ret;
+
+ if (attr->attach_flags)
+ return -EINVAL;
+
+ rcdev = rc_dev_get_from_fd(attr->target_fd);
+ if (IS_ERR(rcdev))
+ return PTR_ERR(rcdev);
+
+ ret = lirc_bpf_attach(rcdev, prog);
+
+ put_device(&rcdev->dev);
+
+ return ret;
+}
+
+int lirc_prog_detach(const union bpf_attr *attr)
+{
+ struct bpf_prog *prog;
+ struct rc_dev *rcdev;
+ int ret;
+
+ if (attr->attach_flags)
+ return -EINVAL;
+
+ prog = bpf_prog_get_type(attr->attach_bpf_fd,
+ BPF_PROG_TYPE_LIRC_MODE2);
+ if (IS_ERR(prog))
+ return PTR_ERR(prog);
+
+ rcdev = rc_dev_get_from_fd(attr->target_fd);
+ if (IS_ERR(rcdev)) {
+ bpf_prog_put(prog);
+ return PTR_ERR(rcdev);
+ }
+
+ ret = lirc_bpf_detach(rcdev, prog);
+
+ bpf_prog_put(prog);
+ put_device(&rcdev->dev);
+
+ return ret;
+}
+
+int lirc_prog_query(const union bpf_attr *attr, union bpf_attr __user *uattr)
+{
+ __u32 __user *prog_ids = u64_to_user_ptr(attr->query.prog_ids);
+ struct bpf_prog_array __rcu *progs;
+ struct rc_dev *rcdev;
+ u32 cnt, flags = 0;
+ int ret;
+
+ if (attr->query.query_flags)
+ return -EINVAL;
+
+ rcdev = rc_dev_get_from_fd(attr->query.target_fd);
+ if (IS_ERR(rcdev))
+ return PTR_ERR(rcdev);
+
+ if (rcdev->driver_type != RC_DRIVER_IR_RAW) {
+ ret = -EINVAL;
+ goto put;
+ }
+
+ ret = mutex_lock_interruptible(&ir_raw_handler_lock);
+ if (ret)
+ goto put;
+
+ progs = rcdev->raw->progs;
+ cnt = progs ? bpf_prog_array_length(progs) : 0;
+
+ if (copy_to_user(&uattr->query.prog_cnt, &cnt, sizeof(cnt))) {
+ ret = -EFAULT;
+ goto unlock;
+ }
+
+ if (copy_to_user(&uattr->query.attach_flags, &flags, sizeof(flags))) {
+ ret = -EFAULT;
+ goto unlock;
+ }
+
+ if (attr->query.prog_cnt != 0 && prog_ids && cnt)
+ ret = bpf_prog_array_copy_to_user(progs, prog_ids, cnt);
+
+unlock:
+ mutex_unlock(&ir_raw_handler_lock);
+put:
+ put_device(&rcdev->dev);
+
+ return ret;
+}