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-rw-r--r--net/bluetooth/coredump.c536
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);