diff options
Diffstat (limited to 'drivers/bluetooth/hci_vhci.c')
| -rw-r--r-- | drivers/bluetooth/hci_vhci.c | 710 |
1 files changed, 710 insertions, 0 deletions
diff --git a/drivers/bluetooth/hci_vhci.c b/drivers/bluetooth/hci_vhci.c new file mode 100644 index 000000000..572d68d52 --- /dev/null +++ b/drivers/bluetooth/hci_vhci.c @@ -0,0 +1,710 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * + * Bluetooth virtual HCI driver + * + * Copyright (C) 2000-2001 Qualcomm Incorporated + * Copyright (C) 2002-2003 Maxim Krasnyansky <maxk@qualcomm.com> + * Copyright (C) 2004-2006 Marcel Holtmann <marcel@holtmann.org> + */ + +#include <linux/module.h> +#include <asm/unaligned.h> + +#include <linux/atomic.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/errno.h> +#include <linux/sched.h> +#include <linux/poll.h> + +#include <linux/skbuff.h> +#include <linux/miscdevice.h> +#include <linux/debugfs.h> + +#include <net/bluetooth/bluetooth.h> +#include <net/bluetooth/hci_core.h> + +#define VERSION "1.5" + +static bool amp; + +struct vhci_data { + struct hci_dev *hdev; + + wait_queue_head_t read_wait; + struct sk_buff_head readq; + + struct mutex open_mutex; + struct delayed_work open_timeout; + struct work_struct suspend_work; + + bool suspended; + bool wakeup; + __u16 msft_opcode; + bool aosp_capable; + atomic_t initialized; +}; + +static int vhci_open_dev(struct hci_dev *hdev) +{ + return 0; +} + +static int vhci_close_dev(struct hci_dev *hdev) +{ + struct vhci_data *data = hci_get_drvdata(hdev); + + skb_queue_purge(&data->readq); + + return 0; +} + +static int vhci_flush(struct hci_dev *hdev) +{ + struct vhci_data *data = hci_get_drvdata(hdev); + + skb_queue_purge(&data->readq); + + return 0; +} + +static int vhci_send_frame(struct hci_dev *hdev, struct sk_buff *skb) +{ + struct vhci_data *data = hci_get_drvdata(hdev); + + memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1); + + skb_queue_tail(&data->readq, skb); + + if (atomic_read(&data->initialized)) + wake_up_interruptible(&data->read_wait); + return 0; +} + +static int vhci_get_data_path_id(struct hci_dev *hdev, u8 *data_path_id) +{ + *data_path_id = 0; + return 0; +} + +static int vhci_get_codec_config_data(struct hci_dev *hdev, __u8 type, + struct bt_codec *codec, __u8 *vnd_len, + __u8 **vnd_data) +{ + if (type != ESCO_LINK) + return -EINVAL; + + *vnd_len = 0; + *vnd_data = NULL; + return 0; +} + +static bool vhci_wakeup(struct hci_dev *hdev) +{ + struct vhci_data *data = hci_get_drvdata(hdev); + + return data->wakeup; +} + +static ssize_t force_suspend_read(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct vhci_data *data = file->private_data; + char buf[3]; + + buf[0] = data->suspended ? 'Y' : 'N'; + buf[1] = '\n'; + buf[2] = '\0'; + return simple_read_from_buffer(user_buf, count, ppos, buf, 2); +} + +static void vhci_suspend_work(struct work_struct *work) +{ + struct vhci_data *data = container_of(work, struct vhci_data, + suspend_work); + + if (data->suspended) + hci_suspend_dev(data->hdev); + else + hci_resume_dev(data->hdev); +} + +static ssize_t force_suspend_write(struct file *file, + const char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct vhci_data *data = file->private_data; + bool enable; + int err; + + err = kstrtobool_from_user(user_buf, count, &enable); + if (err) + return err; + + if (data->suspended == enable) + return -EALREADY; + + data->suspended = enable; + + schedule_work(&data->suspend_work); + + return count; +} + +static const struct file_operations force_suspend_fops = { + .open = simple_open, + .read = force_suspend_read, + .write = force_suspend_write, + .llseek = default_llseek, +}; + +static ssize_t force_wakeup_read(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct vhci_data *data = file->private_data; + char buf[3]; + + buf[0] = data->wakeup ? 'Y' : 'N'; + buf[1] = '\n'; + buf[2] = '\0'; + return simple_read_from_buffer(user_buf, count, ppos, buf, 2); +} + +static ssize_t force_wakeup_write(struct file *file, + const char __user *user_buf, size_t count, + loff_t *ppos) +{ + struct vhci_data *data = file->private_data; + bool enable; + int err; + + err = kstrtobool_from_user(user_buf, count, &enable); + if (err) + return err; + + if (data->wakeup == enable) + return -EALREADY; + + data->wakeup = enable; + + return count; +} + +static const struct file_operations force_wakeup_fops = { + .open = simple_open, + .read = force_wakeup_read, + .write = force_wakeup_write, + .llseek = default_llseek, +}; + +static int msft_opcode_set(void *data, u64 val) +{ + struct vhci_data *vhci = data; + + if (val > 0xffff || hci_opcode_ogf(val) != 0x3f) + return -EINVAL; + + if (vhci->msft_opcode) + return -EALREADY; + + vhci->msft_opcode = val; + + return 0; +} + +static int msft_opcode_get(void *data, u64 *val) +{ + struct vhci_data *vhci = data; + + *val = vhci->msft_opcode; + + return 0; +} + +DEFINE_DEBUGFS_ATTRIBUTE(msft_opcode_fops, msft_opcode_get, msft_opcode_set, + "%llu\n"); + +static ssize_t aosp_capable_read(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct vhci_data *vhci = file->private_data; + char buf[3]; + + buf[0] = vhci->aosp_capable ? 'Y' : 'N'; + buf[1] = '\n'; + buf[2] = '\0'; + return simple_read_from_buffer(user_buf, count, ppos, buf, 2); +} + +static ssize_t aosp_capable_write(struct file *file, + const char __user *user_buf, size_t count, + loff_t *ppos) +{ + struct vhci_data *vhci = file->private_data; + bool enable; + int err; + + err = kstrtobool_from_user(user_buf, count, &enable); + if (err) + return err; + + if (!enable) + return -EINVAL; + + if (vhci->aosp_capable) + return -EALREADY; + + vhci->aosp_capable = enable; + + return count; +} + +static const struct file_operations aosp_capable_fops = { + .open = simple_open, + .read = aosp_capable_read, + .write = aosp_capable_write, + .llseek = default_llseek, +}; + +static int vhci_setup(struct hci_dev *hdev) +{ + struct vhci_data *vhci = hci_get_drvdata(hdev); + + if (vhci->msft_opcode) + hci_set_msft_opcode(hdev, vhci->msft_opcode); + + if (vhci->aosp_capable) + hci_set_aosp_capable(hdev); + + return 0; +} + +static void vhci_coredump(struct hci_dev *hdev) +{ + /* No need to do anything */ +} + +static void vhci_coredump_hdr(struct hci_dev *hdev, struct sk_buff *skb) +{ + char buf[80]; + + snprintf(buf, sizeof(buf), "Controller Name: vhci_ctrl\n"); + skb_put_data(skb, buf, strlen(buf)); + + snprintf(buf, sizeof(buf), "Firmware Version: vhci_fw\n"); + skb_put_data(skb, buf, strlen(buf)); + + snprintf(buf, sizeof(buf), "Driver: vhci_drv\n"); + skb_put_data(skb, buf, strlen(buf)); + + snprintf(buf, sizeof(buf), "Vendor: vhci\n"); + skb_put_data(skb, buf, strlen(buf)); +} + +#define MAX_COREDUMP_LINE_LEN 40 + +struct devcoredump_test_data { + enum devcoredump_state state; + unsigned int timeout; + char data[MAX_COREDUMP_LINE_LEN]; +}; + +static inline void force_devcd_timeout(struct hci_dev *hdev, + unsigned int timeout) +{ +#ifdef CONFIG_DEV_COREDUMP + hdev->dump.timeout = msecs_to_jiffies(timeout * 1000); +#endif +} + +static ssize_t force_devcd_write(struct file *file, const char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct vhci_data *data = file->private_data; + struct hci_dev *hdev = data->hdev; + struct sk_buff *skb = NULL; + struct devcoredump_test_data dump_data; + size_t data_size; + int ret; + + if (count < offsetof(struct devcoredump_test_data, data) || + count > sizeof(dump_data)) + return -EINVAL; + + if (copy_from_user(&dump_data, user_buf, count)) + return -EFAULT; + + data_size = count - offsetof(struct devcoredump_test_data, data); + skb = alloc_skb(data_size, GFP_ATOMIC); + if (!skb) + return -ENOMEM; + skb_put_data(skb, &dump_data.data, data_size); + + hci_devcd_register(hdev, vhci_coredump, vhci_coredump_hdr, NULL); + + /* Force the devcoredump timeout */ + if (dump_data.timeout) + force_devcd_timeout(hdev, dump_data.timeout); + + ret = hci_devcd_init(hdev, skb->len); + if (ret) { + BT_ERR("Failed to generate devcoredump"); + kfree_skb(skb); + return ret; + } + + hci_devcd_append(hdev, skb); + + switch (dump_data.state) { + case HCI_DEVCOREDUMP_DONE: + hci_devcd_complete(hdev); + break; + case HCI_DEVCOREDUMP_ABORT: + hci_devcd_abort(hdev); + break; + case HCI_DEVCOREDUMP_TIMEOUT: + /* Do nothing */ + break; + default: + return -EINVAL; + } + + return count; +} + +static const struct file_operations force_devcoredump_fops = { + .open = simple_open, + .write = force_devcd_write, +}; + +static int __vhci_create_device(struct vhci_data *data, __u8 opcode) +{ + struct hci_dev *hdev; + struct sk_buff *skb; + __u8 dev_type; + + if (data->hdev) + return -EBADFD; + + /* bits 0-1 are dev_type (Primary or AMP) */ + dev_type = opcode & 0x03; + + if (dev_type != HCI_PRIMARY && dev_type != HCI_AMP) + return -EINVAL; + + /* bits 2-5 are reserved (must be zero) */ + if (opcode & 0x3c) + return -EINVAL; + + skb = bt_skb_alloc(4, GFP_KERNEL); + if (!skb) + return -ENOMEM; + + hdev = hci_alloc_dev(); + if (!hdev) { + kfree_skb(skb); + return -ENOMEM; + } + + data->hdev = hdev; + + hdev->bus = HCI_VIRTUAL; + hdev->dev_type = dev_type; + hci_set_drvdata(hdev, data); + + hdev->open = vhci_open_dev; + hdev->close = vhci_close_dev; + hdev->flush = vhci_flush; + hdev->send = vhci_send_frame; + hdev->get_data_path_id = vhci_get_data_path_id; + hdev->get_codec_config_data = vhci_get_codec_config_data; + hdev->wakeup = vhci_wakeup; + hdev->setup = vhci_setup; + set_bit(HCI_QUIRK_NON_PERSISTENT_SETUP, &hdev->quirks); + + /* bit 6 is for external configuration */ + if (opcode & 0x40) + set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks); + + /* bit 7 is for raw device */ + if (opcode & 0x80) + set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks); + + set_bit(HCI_QUIRK_VALID_LE_STATES, &hdev->quirks); + + if (hci_register_dev(hdev) < 0) { + BT_ERR("Can't register HCI device"); + hci_free_dev(hdev); + data->hdev = NULL; + kfree_skb(skb); + return -EBUSY; + } + + debugfs_create_file("force_suspend", 0644, hdev->debugfs, data, + &force_suspend_fops); + + debugfs_create_file("force_wakeup", 0644, hdev->debugfs, data, + &force_wakeup_fops); + + if (IS_ENABLED(CONFIG_BT_MSFTEXT)) + debugfs_create_file("msft_opcode", 0644, hdev->debugfs, data, + &msft_opcode_fops); + + if (IS_ENABLED(CONFIG_BT_AOSPEXT)) + debugfs_create_file("aosp_capable", 0644, hdev->debugfs, data, + &aosp_capable_fops); + + debugfs_create_file("force_devcoredump", 0644, hdev->debugfs, data, + &force_devcoredump_fops); + + hci_skb_pkt_type(skb) = HCI_VENDOR_PKT; + + skb_put_u8(skb, 0xff); + skb_put_u8(skb, opcode); + put_unaligned_le16(hdev->id, skb_put(skb, 2)); + skb_queue_head(&data->readq, skb); + atomic_inc(&data->initialized); + + wake_up_interruptible(&data->read_wait); + return 0; +} + +static int vhci_create_device(struct vhci_data *data, __u8 opcode) +{ + int err; + + mutex_lock(&data->open_mutex); + err = __vhci_create_device(data, opcode); + mutex_unlock(&data->open_mutex); + + return err; +} + +static inline ssize_t vhci_get_user(struct vhci_data *data, + struct iov_iter *from) +{ + size_t len = iov_iter_count(from); + struct sk_buff *skb; + __u8 pkt_type, opcode; + int ret; + + if (len < 2 || len > HCI_MAX_FRAME_SIZE) + return -EINVAL; + + skb = bt_skb_alloc(len, GFP_KERNEL); + if (!skb) + return -ENOMEM; + + if (!copy_from_iter_full(skb_put(skb, len), len, from)) { + kfree_skb(skb); + return -EFAULT; + } + + pkt_type = *((__u8 *) skb->data); + skb_pull(skb, 1); + + switch (pkt_type) { + case HCI_EVENT_PKT: + case HCI_ACLDATA_PKT: + case HCI_SCODATA_PKT: + case HCI_ISODATA_PKT: + if (!data->hdev) { + kfree_skb(skb); + return -ENODEV; + } + + hci_skb_pkt_type(skb) = pkt_type; + + ret = hci_recv_frame(data->hdev, skb); + break; + + case HCI_VENDOR_PKT: + cancel_delayed_work_sync(&data->open_timeout); + + opcode = *((__u8 *) skb->data); + skb_pull(skb, 1); + + if (skb->len > 0) { + kfree_skb(skb); + return -EINVAL; + } + + kfree_skb(skb); + + ret = vhci_create_device(data, opcode); + break; + + default: + kfree_skb(skb); + return -EINVAL; + } + + return (ret < 0) ? ret : len; +} + +static inline ssize_t vhci_put_user(struct vhci_data *data, + struct sk_buff *skb, + char __user *buf, int count) +{ + char __user *ptr = buf; + int len; + + len = min_t(unsigned int, skb->len, count); + + if (copy_to_user(ptr, skb->data, len)) + return -EFAULT; + + if (!data->hdev) + return len; + + data->hdev->stat.byte_tx += len; + + switch (hci_skb_pkt_type(skb)) { + case HCI_COMMAND_PKT: + data->hdev->stat.cmd_tx++; + break; + case HCI_ACLDATA_PKT: + data->hdev->stat.acl_tx++; + break; + case HCI_SCODATA_PKT: + data->hdev->stat.sco_tx++; + break; + } + + return len; +} + +static ssize_t vhci_read(struct file *file, + char __user *buf, size_t count, loff_t *pos) +{ + struct vhci_data *data = file->private_data; + struct sk_buff *skb; + ssize_t ret = 0; + + while (count) { + skb = skb_dequeue(&data->readq); + if (skb) { + ret = vhci_put_user(data, skb, buf, count); + if (ret < 0) + skb_queue_head(&data->readq, skb); + else + kfree_skb(skb); + break; + } + + if (file->f_flags & O_NONBLOCK) { + ret = -EAGAIN; + break; + } + + ret = wait_event_interruptible(data->read_wait, + !skb_queue_empty(&data->readq)); + if (ret < 0) + break; + } + + return ret; +} + +static ssize_t vhci_write(struct kiocb *iocb, struct iov_iter *from) +{ + struct file *file = iocb->ki_filp; + struct vhci_data *data = file->private_data; + + return vhci_get_user(data, from); +} + +static __poll_t vhci_poll(struct file *file, poll_table *wait) +{ + struct vhci_data *data = file->private_data; + + poll_wait(file, &data->read_wait, wait); + + if (!skb_queue_empty(&data->readq)) + return EPOLLIN | EPOLLRDNORM; + + return EPOLLOUT | EPOLLWRNORM; +} + +static void vhci_open_timeout(struct work_struct *work) +{ + struct vhci_data *data = container_of(work, struct vhci_data, + open_timeout.work); + + vhci_create_device(data, amp ? HCI_AMP : HCI_PRIMARY); +} + +static int vhci_open(struct inode *inode, struct file *file) +{ + struct vhci_data *data; + + data = kzalloc(sizeof(struct vhci_data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + skb_queue_head_init(&data->readq); + init_waitqueue_head(&data->read_wait); + + mutex_init(&data->open_mutex); + INIT_DELAYED_WORK(&data->open_timeout, vhci_open_timeout); + INIT_WORK(&data->suspend_work, vhci_suspend_work); + + file->private_data = data; + nonseekable_open(inode, file); + + schedule_delayed_work(&data->open_timeout, msecs_to_jiffies(1000)); + + return 0; +} + +static int vhci_release(struct inode *inode, struct file *file) +{ + struct vhci_data *data = file->private_data; + struct hci_dev *hdev; + + cancel_delayed_work_sync(&data->open_timeout); + flush_work(&data->suspend_work); + + hdev = data->hdev; + + if (hdev) { + hci_unregister_dev(hdev); + hci_free_dev(hdev); + } + + skb_queue_purge(&data->readq); + file->private_data = NULL; + kfree(data); + + return 0; +} + +static const struct file_operations vhci_fops = { + .owner = THIS_MODULE, + .read = vhci_read, + .write_iter = vhci_write, + .poll = vhci_poll, + .open = vhci_open, + .release = vhci_release, + .llseek = no_llseek, +}; + +static struct miscdevice vhci_miscdev = { + .name = "vhci", + .fops = &vhci_fops, + .minor = VHCI_MINOR, +}; +module_misc_device(vhci_miscdev); + +module_param(amp, bool, 0644); +MODULE_PARM_DESC(amp, "Create AMP controller device"); + +MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>"); +MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION); +MODULE_VERSION(VERSION); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("devname:vhci"); +MODULE_ALIAS_MISCDEV(VHCI_MINOR); |