diff options
Diffstat (limited to 'net/bluetooth/coredump.c')
| -rw-r--r-- | net/bluetooth/coredump.c | 536 |
1 files changed, 536 insertions, 0 deletions
diff --git a/net/bluetooth/coredump.c b/net/bluetooth/coredump.c new file mode 100644 index 000000000000..d2d2624ec708 --- /dev/null +++ b/net/bluetooth/coredump.c @@ -0,0 +1,536 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2023 Google Corporation + */ + +#include <linux/devcoredump.h> + +#include <asm/unaligned.h> +#include <net/bluetooth/bluetooth.h> +#include <net/bluetooth/hci_core.h> + +enum hci_devcoredump_pkt_type { + HCI_DEVCOREDUMP_PKT_INIT, + HCI_DEVCOREDUMP_PKT_SKB, + HCI_DEVCOREDUMP_PKT_PATTERN, + HCI_DEVCOREDUMP_PKT_COMPLETE, + HCI_DEVCOREDUMP_PKT_ABORT, +}; + +struct hci_devcoredump_skb_cb { + u16 pkt_type; +}; + +struct hci_devcoredump_skb_pattern { + u8 pattern; + u32 len; +} __packed; + +#define hci_dmp_cb(skb) ((struct hci_devcoredump_skb_cb *)((skb)->cb)) + +#define DBG_UNEXPECTED_STATE() \ + bt_dev_dbg(hdev, \ + "Unexpected packet (%d) for state (%d). ", \ + hci_dmp_cb(skb)->pkt_type, hdev->dump.state) + +#define MAX_DEVCOREDUMP_HDR_SIZE 512 /* bytes */ + +static int hci_devcd_update_hdr_state(char *buf, size_t size, int state) +{ + int len = 0; + + if (!buf) + return 0; + + len = scnprintf(buf, size, "Bluetooth devcoredump\nState: %d\n", state); + + return len + 1; /* scnprintf adds \0 at the end upon state rewrite */ +} + +/* Call with hci_dev_lock only. */ +static int hci_devcd_update_state(struct hci_dev *hdev, int state) +{ + bt_dev_dbg(hdev, "Updating devcoredump state from %d to %d.", + hdev->dump.state, state); + + hdev->dump.state = state; + + return hci_devcd_update_hdr_state(hdev->dump.head, + hdev->dump.alloc_size, state); +} + +static int hci_devcd_mkheader(struct hci_dev *hdev, struct sk_buff *skb) +{ + char dump_start[] = "--- Start dump ---\n"; + char hdr[80]; + int hdr_len; + + hdr_len = hci_devcd_update_hdr_state(hdr, sizeof(hdr), + HCI_DEVCOREDUMP_IDLE); + skb_put_data(skb, hdr, hdr_len); + + if (hdev->dump.dmp_hdr) + hdev->dump.dmp_hdr(hdev, skb); + + skb_put_data(skb, dump_start, strlen(dump_start)); + + return skb->len; +} + +/* Do not call with hci_dev_lock since this calls driver code. */ +static void hci_devcd_notify(struct hci_dev *hdev, int state) +{ + if (hdev->dump.notify_change) + hdev->dump.notify_change(hdev, state); +} + +/* Call with hci_dev_lock only. */ +void hci_devcd_reset(struct hci_dev *hdev) +{ + hdev->dump.head = NULL; + hdev->dump.tail = NULL; + hdev->dump.alloc_size = 0; + + hci_devcd_update_state(hdev, HCI_DEVCOREDUMP_IDLE); + + cancel_delayed_work(&hdev->dump.dump_timeout); + skb_queue_purge(&hdev->dump.dump_q); +} + +/* Call with hci_dev_lock only. */ +static void hci_devcd_free(struct hci_dev *hdev) +{ + if (hdev->dump.head) + vfree(hdev->dump.head); + + hci_devcd_reset(hdev); +} + +/* Call with hci_dev_lock only. */ +static int hci_devcd_alloc(struct hci_dev *hdev, u32 size) +{ + hdev->dump.head = vmalloc(size); + if (!hdev->dump.head) + return -ENOMEM; + + hdev->dump.alloc_size = size; + hdev->dump.tail = hdev->dump.head; + hdev->dump.end = hdev->dump.head + size; + + hci_devcd_update_state(hdev, HCI_DEVCOREDUMP_IDLE); + + return 0; +} + +/* Call with hci_dev_lock only. */ +static bool hci_devcd_copy(struct hci_dev *hdev, char *buf, u32 size) +{ + if (hdev->dump.tail + size > hdev->dump.end) + return false; + + memcpy(hdev->dump.tail, buf, size); + hdev->dump.tail += size; + + return true; +} + +/* Call with hci_dev_lock only. */ +static bool hci_devcd_memset(struct hci_dev *hdev, u8 pattern, u32 len) +{ + if (hdev->dump.tail + len > hdev->dump.end) + return false; + + memset(hdev->dump.tail, pattern, len); + hdev->dump.tail += len; + + return true; +} + +/* Call with hci_dev_lock only. */ +static int hci_devcd_prepare(struct hci_dev *hdev, u32 dump_size) +{ + struct sk_buff *skb; + int dump_hdr_size; + int err = 0; + + skb = alloc_skb(MAX_DEVCOREDUMP_HDR_SIZE, GFP_ATOMIC); + if (!skb) + return -ENOMEM; + + dump_hdr_size = hci_devcd_mkheader(hdev, skb); + + if (hci_devcd_alloc(hdev, dump_hdr_size + dump_size)) { + err = -ENOMEM; + goto hdr_free; + } + + /* Insert the device header */ + if (!hci_devcd_copy(hdev, skb->data, skb->len)) { + bt_dev_err(hdev, "Failed to insert header"); + hci_devcd_free(hdev); + + err = -ENOMEM; + goto hdr_free; + } + +hdr_free: + kfree_skb(skb); + + return err; +} + +static void hci_devcd_handle_pkt_init(struct hci_dev *hdev, struct sk_buff *skb) +{ + u32 dump_size; + + if (hdev->dump.state != HCI_DEVCOREDUMP_IDLE) { + DBG_UNEXPECTED_STATE(); + return; + } + + if (skb->len != sizeof(dump_size)) { + bt_dev_dbg(hdev, "Invalid dump init pkt"); + return; + } + + dump_size = get_unaligned_le32(skb_pull_data(skb, 4)); + if (!dump_size) { + bt_dev_err(hdev, "Zero size dump init pkt"); + return; + } + + if (hci_devcd_prepare(hdev, dump_size)) { + bt_dev_err(hdev, "Failed to prepare for dump"); + return; + } + + hci_devcd_update_state(hdev, HCI_DEVCOREDUMP_ACTIVE); + queue_delayed_work(hdev->workqueue, &hdev->dump.dump_timeout, + hdev->dump.timeout); +} + +static void hci_devcd_handle_pkt_skb(struct hci_dev *hdev, struct sk_buff *skb) +{ + if (hdev->dump.state != HCI_DEVCOREDUMP_ACTIVE) { + DBG_UNEXPECTED_STATE(); + return; + } + + if (!hci_devcd_copy(hdev, skb->data, skb->len)) + bt_dev_dbg(hdev, "Failed to insert skb"); +} + +static void hci_devcd_handle_pkt_pattern(struct hci_dev *hdev, + struct sk_buff *skb) +{ + struct hci_devcoredump_skb_pattern *pattern; + + if (hdev->dump.state != HCI_DEVCOREDUMP_ACTIVE) { + DBG_UNEXPECTED_STATE(); + return; + } + + if (skb->len != sizeof(*pattern)) { + bt_dev_dbg(hdev, "Invalid pattern skb"); + return; + } + + pattern = skb_pull_data(skb, sizeof(*pattern)); + + if (!hci_devcd_memset(hdev, pattern->pattern, pattern->len)) + bt_dev_dbg(hdev, "Failed to set pattern"); +} + +static void hci_devcd_handle_pkt_complete(struct hci_dev *hdev, + struct sk_buff *skb) +{ + u32 dump_size; + + if (hdev->dump.state != HCI_DEVCOREDUMP_ACTIVE) { + DBG_UNEXPECTED_STATE(); + return; + } + + hci_devcd_update_state(hdev, HCI_DEVCOREDUMP_DONE); + dump_size = hdev->dump.tail - hdev->dump.head; + + bt_dev_dbg(hdev, "complete with size %u (expect %zu)", dump_size, + hdev->dump.alloc_size); + + dev_coredumpv(&hdev->dev, hdev->dump.head, dump_size, GFP_KERNEL); +} + +static void hci_devcd_handle_pkt_abort(struct hci_dev *hdev, + struct sk_buff *skb) +{ + u32 dump_size; + + if (hdev->dump.state != HCI_DEVCOREDUMP_ACTIVE) { + DBG_UNEXPECTED_STATE(); + return; + } + + hci_devcd_update_state(hdev, HCI_DEVCOREDUMP_ABORT); + dump_size = hdev->dump.tail - hdev->dump.head; + + bt_dev_dbg(hdev, "aborted with size %u (expect %zu)", dump_size, + hdev->dump.alloc_size); + + /* Emit a devcoredump with the available data */ + dev_coredumpv(&hdev->dev, hdev->dump.head, dump_size, GFP_KERNEL); +} + +/* Bluetooth devcoredump state machine. + * + * Devcoredump states: + * + * HCI_DEVCOREDUMP_IDLE: The default state. + * + * HCI_DEVCOREDUMP_ACTIVE: A devcoredump will be in this state once it has + * been initialized using hci_devcd_init(). Once active, the driver + * can append data using hci_devcd_append() or insert a pattern + * using hci_devcd_append_pattern(). + * + * HCI_DEVCOREDUMP_DONE: Once the dump collection is complete, the drive + * can signal the completion using hci_devcd_complete(). A + * devcoredump is generated indicating the completion event and + * then the state machine is reset to the default state. + * + * HCI_DEVCOREDUMP_ABORT: The driver can cancel ongoing dump collection in + * case of any error using hci_devcd_abort(). A devcoredump is + * still generated with the available data indicating the abort + * event and then the state machine is reset to the default state. + * + * HCI_DEVCOREDUMP_TIMEOUT: A timeout timer for HCI_DEVCOREDUMP_TIMEOUT sec + * is started during devcoredump initialization. Once the timeout + * occurs, the driver is notified, a devcoredump is generated with + * the available data indicating the timeout event and then the + * state machine is reset to the default state. + * + * The driver must register using hci_devcd_register() before using the hci + * devcoredump APIs. + */ +void hci_devcd_rx(struct work_struct *work) +{ + struct hci_dev *hdev = container_of(work, struct hci_dev, dump.dump_rx); + struct sk_buff *skb; + int start_state; + + while ((skb = skb_dequeue(&hdev->dump.dump_q))) { + /* Return if timeout occurs. The timeout handler function + * hci_devcd_timeout() will report the available dump data. + */ + if (hdev->dump.state == HCI_DEVCOREDUMP_TIMEOUT) { + kfree_skb(skb); + return; + } + + hci_dev_lock(hdev); + start_state = hdev->dump.state; + + switch (hci_dmp_cb(skb)->pkt_type) { + case HCI_DEVCOREDUMP_PKT_INIT: + hci_devcd_handle_pkt_init(hdev, skb); + break; + + case HCI_DEVCOREDUMP_PKT_SKB: + hci_devcd_handle_pkt_skb(hdev, skb); + break; + + case HCI_DEVCOREDUMP_PKT_PATTERN: + hci_devcd_handle_pkt_pattern(hdev, skb); + break; + + case HCI_DEVCOREDUMP_PKT_COMPLETE: + hci_devcd_handle_pkt_complete(hdev, skb); + break; + + case HCI_DEVCOREDUMP_PKT_ABORT: + hci_devcd_handle_pkt_abort(hdev, skb); + break; + + default: + bt_dev_dbg(hdev, "Unknown packet (%d) for state (%d). ", + hci_dmp_cb(skb)->pkt_type, hdev->dump.state); + break; + } + + hci_dev_unlock(hdev); + kfree_skb(skb); + + /* Notify the driver about any state changes before resetting + * the state machine + */ + if (start_state != hdev->dump.state) + hci_devcd_notify(hdev, hdev->dump.state); + + /* Reset the state machine if the devcoredump is complete */ + hci_dev_lock(hdev); + if (hdev->dump.state == HCI_DEVCOREDUMP_DONE || + hdev->dump.state == HCI_DEVCOREDUMP_ABORT) + hci_devcd_reset(hdev); + hci_dev_unlock(hdev); + } +} +EXPORT_SYMBOL(hci_devcd_rx); + +void hci_devcd_timeout(struct work_struct *work) +{ + struct hci_dev *hdev = container_of(work, struct hci_dev, + dump.dump_timeout.work); + u32 dump_size; + + hci_devcd_notify(hdev, HCI_DEVCOREDUMP_TIMEOUT); + + hci_dev_lock(hdev); + + cancel_work(&hdev->dump.dump_rx); + + hci_devcd_update_state(hdev, HCI_DEVCOREDUMP_TIMEOUT); + + dump_size = hdev->dump.tail - hdev->dump.head; + bt_dev_dbg(hdev, "timeout with size %u (expect %zu)", dump_size, + hdev->dump.alloc_size); + + /* Emit a devcoredump with the available data */ + dev_coredumpv(&hdev->dev, hdev->dump.head, dump_size, GFP_KERNEL); + + hci_devcd_reset(hdev); + + hci_dev_unlock(hdev); +} +EXPORT_SYMBOL(hci_devcd_timeout); + +int hci_devcd_register(struct hci_dev *hdev, coredump_t coredump, + dmp_hdr_t dmp_hdr, notify_change_t notify_change) +{ + /* Driver must implement coredump() and dmp_hdr() functions for + * bluetooth devcoredump. The coredump() should trigger a coredump + * event on the controller when the device's coredump sysfs entry is + * written to. The dmp_hdr() should create a dump header to identify + * the controller/fw/driver info. + */ + if (!coredump || !dmp_hdr) + return -EINVAL; + + hci_dev_lock(hdev); + hdev->dump.coredump = coredump; + hdev->dump.dmp_hdr = dmp_hdr; + hdev->dump.notify_change = notify_change; + hdev->dump.supported = true; + hdev->dump.timeout = DEVCOREDUMP_TIMEOUT; + hci_dev_unlock(hdev); + + return 0; +} +EXPORT_SYMBOL(hci_devcd_register); + +static inline bool hci_devcd_enabled(struct hci_dev *hdev) +{ + return hdev->dump.supported; +} + +int hci_devcd_init(struct hci_dev *hdev, u32 dump_size) +{ + struct sk_buff *skb; + + if (!hci_devcd_enabled(hdev)) + return -EOPNOTSUPP; + + skb = alloc_skb(sizeof(dump_size), GFP_ATOMIC); + if (!skb) + return -ENOMEM; + + hci_dmp_cb(skb)->pkt_type = HCI_DEVCOREDUMP_PKT_INIT; + put_unaligned_le32(dump_size, skb_put(skb, 4)); + + skb_queue_tail(&hdev->dump.dump_q, skb); + queue_work(hdev->workqueue, &hdev->dump.dump_rx); + + return 0; +} +EXPORT_SYMBOL(hci_devcd_init); + +int hci_devcd_append(struct hci_dev *hdev, struct sk_buff *skb) +{ + if (!skb) + return -ENOMEM; + + if (!hci_devcd_enabled(hdev)) { + kfree_skb(skb); + return -EOPNOTSUPP; + } + + hci_dmp_cb(skb)->pkt_type = HCI_DEVCOREDUMP_PKT_SKB; + + skb_queue_tail(&hdev->dump.dump_q, skb); + queue_work(hdev->workqueue, &hdev->dump.dump_rx); + + return 0; +} +EXPORT_SYMBOL(hci_devcd_append); + +int hci_devcd_append_pattern(struct hci_dev *hdev, u8 pattern, u32 len) +{ + struct hci_devcoredump_skb_pattern p; + struct sk_buff *skb; + + if (!hci_devcd_enabled(hdev)) + return -EOPNOTSUPP; + + skb = alloc_skb(sizeof(p), GFP_ATOMIC); + if (!skb) + return -ENOMEM; + + p.pattern = pattern; + p.len = len; + + hci_dmp_cb(skb)->pkt_type = HCI_DEVCOREDUMP_PKT_PATTERN; + skb_put_data(skb, &p, sizeof(p)); + + skb_queue_tail(&hdev->dump.dump_q, skb); + queue_work(hdev->workqueue, &hdev->dump.dump_rx); + + return 0; +} +EXPORT_SYMBOL(hci_devcd_append_pattern); + +int hci_devcd_complete(struct hci_dev *hdev) +{ + struct sk_buff *skb; + + if (!hci_devcd_enabled(hdev)) + return -EOPNOTSUPP; + + skb = alloc_skb(0, GFP_ATOMIC); + if (!skb) + return -ENOMEM; + + hci_dmp_cb(skb)->pkt_type = HCI_DEVCOREDUMP_PKT_COMPLETE; + + skb_queue_tail(&hdev->dump.dump_q, skb); + queue_work(hdev->workqueue, &hdev->dump.dump_rx); + + return 0; +} +EXPORT_SYMBOL(hci_devcd_complete); + +int hci_devcd_abort(struct hci_dev *hdev) +{ + struct sk_buff *skb; + + if (!hci_devcd_enabled(hdev)) + return -EOPNOTSUPP; + + skb = alloc_skb(0, GFP_ATOMIC); + if (!skb) + return -ENOMEM; + + hci_dmp_cb(skb)->pkt_type = HCI_DEVCOREDUMP_PKT_ABORT; + + skb_queue_tail(&hdev->dump.dump_q, skb); + queue_work(hdev->workqueue, &hdev->dump.dump_rx); + + return 0; +} +EXPORT_SYMBOL(hci_devcd_abort); |