1 files changed, 221 insertions, 2 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-trans.c b/drivers/net/wireless/intel/iwlwifi/iwl-trans.c
index 3c9d91496c826..49c8507d1a6b1 100644
--- a/drivers/net/wireless/intel/iwlwifi/iwl-trans.c
+++ b/drivers/net/wireless/intel/iwlwifi/iwl-trans.c
@@ -6,6 +6,7 @@
  */
 #include <linux/kernel.h>
 #include <linux/bsearch.h>
+#include <linux/list.h>
 
 #include "fw/api/tx.h"
 #include "iwl-trans.h"
@@ -16,13 +17,200 @@
 #include "pcie/internal.h"
 #include "iwl-context-info-gen3.h"
 
+struct iwl_trans_dev_restart_data {
+	struct list_head list;
+	unsigned int restart_count;
+	time64_t last_error;
+	char name[];
+};
+
+static LIST_HEAD(restart_data_list);
+static DEFINE_SPINLOCK(restart_data_lock);
+
+static struct iwl_trans_dev_restart_data *
+iwl_trans_get_restart_data(struct device *dev)
+{
+	struct iwl_trans_dev_restart_data *tmp, *data = NULL;
+	const char *name = dev_name(dev);
+
+	spin_lock(&restart_data_lock);
+	list_for_each_entry(tmp, &restart_data_list, list) {
+		if (strcmp(tmp->name, name))
+			continue;
+		data = tmp;
+		break;
+	}
+	spin_unlock(&restart_data_lock);
+
+	if (data)
+		return data;
+
+	data = kzalloc(struct_size(data, name, strlen(name) + 1), GFP_ATOMIC);
+	if (!data)
+		return NULL;
+
+	strcpy(data->name, name);
+	spin_lock(&restart_data_lock);
+	list_add_tail(&data->list, &restart_data_list);
+	spin_unlock(&restart_data_lock);
+
+	return data;
+}
+
+static void iwl_trans_inc_restart_count(struct device *dev)
+{
+	struct iwl_trans_dev_restart_data *data;
+
+	data = iwl_trans_get_restart_data(dev);
+	if (data) {
+		data->last_error = ktime_get_boottime_seconds();
+		data->restart_count++;
+	}
+}
+
+void iwl_trans_free_restart_list(void)
+{
+	struct iwl_trans_dev_restart_data *tmp;
+
+	while ((tmp = list_first_entry_or_null(&restart_data_list,
+					       typeof(*tmp), list))) {
+		list_del(&tmp->list);
+		kfree(tmp);
+	}
+}
+
+struct iwl_trans_reprobe {
+	struct device *dev;
+	struct work_struct work;
+};
+
+static void iwl_trans_reprobe_wk(struct work_struct *wk)
+{
+	struct iwl_trans_reprobe *reprobe;
+
+	reprobe = container_of(wk, typeof(*reprobe), work);
+
+	if (device_reprobe(reprobe->dev))
+		dev_err(reprobe->dev, "reprobe failed!\n");
+	put_device(reprobe->dev);
+	kfree(reprobe);
+	module_put(THIS_MODULE);
+}
+
+#define IWL_TRANS_RESET_OK_TIME	180 /* seconds */
+
+static enum iwl_reset_mode
+iwl_trans_determine_restart_mode(struct iwl_trans *trans)
+{
+	struct iwl_trans_dev_restart_data *data;
+	enum iwl_reset_mode at_least = 0;
+	unsigned int index;
+	static const enum iwl_reset_mode escalation_list[] = {
+		IWL_RESET_MODE_SW_RESET,
+		IWL_RESET_MODE_REPROBE,
+		IWL_RESET_MODE_REPROBE,
+		IWL_RESET_MODE_FUNC_RESET,
+		/* FIXME: add TOP reset */
+		IWL_RESET_MODE_PROD_RESET,
+		/* FIXME: add TOP reset */
+		IWL_RESET_MODE_PROD_RESET,
+		/* FIXME: add TOP reset */
+		IWL_RESET_MODE_PROD_RESET,
+	};
+
+	if (trans->restart.during_reset)
+		at_least = IWL_RESET_MODE_REPROBE;
+
+	data = iwl_trans_get_restart_data(trans->dev);
+	if (!data)
+		return at_least;
+
+	if (ktime_get_boottime_seconds() - data->last_error >=
+			IWL_TRANS_RESET_OK_TIME)
+		data->restart_count = 0;
+
+	index = data->restart_count;
+	if (index >= ARRAY_SIZE(escalation_list))
+		index = ARRAY_SIZE(escalation_list) - 1;
+
+	return max(at_least, escalation_list[index]);
+}
+
+#define IWL_TRANS_RESET_DELAY	(HZ * 60)
+
+static void iwl_trans_restart_wk(struct work_struct *wk)
+{
+	struct iwl_trans *trans = container_of(wk, typeof(*trans), restart.wk);
+	struct iwl_trans_reprobe *reprobe;
+	enum iwl_reset_mode mode;
+
+	if (!trans->op_mode)
+		return;
+
+	/* might have been scheduled before marked as dead, re-check */
+	if (test_bit(STATUS_TRANS_DEAD, &trans->status))
+		return;
+
+	iwl_op_mode_dump_error(trans->op_mode, &trans->restart.mode);
+
+	/*
+	 * If the opmode stopped the device while we were trying to dump and
+	 * reset, then we'll have done the dump already (synchronized by the
+	 * opmode lock that it will acquire in iwl_op_mode_dump_error()) and
+	 * managed that via trans->restart.mode.
+	 * Additionally, make sure that in such a case we won't attempt to do
+	 * any resets now, since it's no longer requested.
+	 */
+	if (!test_and_clear_bit(STATUS_RESET_PENDING, &trans->status))
+		return;
+
+	if (!iwlwifi_mod_params.fw_restart)
+		return;
+
+	mode = iwl_trans_determine_restart_mode(trans);
+
+	iwl_trans_inc_restart_count(trans->dev);
+
+	switch (mode) {
+	case IWL_RESET_MODE_SW_RESET:
+		IWL_ERR(trans, "Device error - SW reset\n");
+		iwl_trans_opmode_sw_reset(trans, trans->restart.mode.type);
+		break;
+	case IWL_RESET_MODE_REPROBE:
+		IWL_ERR(trans, "Device error - reprobe!\n");
+
+		/*
+		 * get a module reference to avoid doing this while unloading
+		 * anyway and to avoid scheduling a work with code that's
+		 * being removed.
+		 */
+		if (!try_module_get(THIS_MODULE)) {
+			IWL_ERR(trans, "Module is being unloaded - abort\n");
+			return;
+		}
+
+		reprobe = kzalloc(sizeof(*reprobe), GFP_KERNEL);
+		if (!reprobe) {
+			module_put(THIS_MODULE);
+			return;
+		}
+		reprobe->dev = get_device(trans->dev);
+		INIT_WORK(&reprobe->work, iwl_trans_reprobe_wk);
+		schedule_work(&reprobe->work);
+		break;
+	default:
+		iwl_trans_pcie_reset(trans, mode);
+		break;
+	}
+}
+
 struct iwl_trans *iwl_trans_alloc(unsigned int priv_size,
 				  struct device *dev,
 				  const struct iwl_cfg_trans_params *cfg_trans)
 {
 	struct iwl_trans *trans;
 #ifdef CONFIG_LOCKDEP
-	static struct lock_class_key __key;
+	static struct lock_class_key __sync_cmd_key;
 #endif
 
 	trans = devm_kzalloc(dev, sizeof(*trans) + priv_size, GFP_KERNEL);
@@ -33,12 +221,14 @@ struct iwl_trans *iwl_trans_alloc(unsigned int priv_size,
 
 #ifdef CONFIG_LOCKDEP
 	lockdep_init_map(&trans->sync_cmd_lockdep_map, "sync_cmd_lockdep_map",
-			 &__key, 0);
+			 &__sync_cmd_key, 0);
 #endif
 
 	trans->dev = dev;
 	trans->num_rx_queues = 1;
 
+	INIT_WORK(&trans->restart.wk, iwl_trans_restart_wk);
+
 	return trans;
 }
 
@@ -81,6 +271,7 @@ int iwl_trans_init(struct iwl_trans *trans)
 
 void iwl_trans_free(struct iwl_trans *trans)
 {
+	cancel_work_sync(&trans->restart.wk);
 	kmem_cache_destroy(trans->dev_cmd_pool);
 }
 
@@ -391,6 +582,34 @@ void iwl_trans_stop_device(struct iwl_trans *trans)
 {
 	might_sleep();
 
+	/*
+	 * See also the comment in iwl_trans_restart_wk().
+	 *
+	 * When the opmode stops the device while a reset is pending, the
+	 * worker (iwl_trans_restart_wk) might not have run yet or, more
+	 * likely, will be blocked on the opmode lock. Due to the locking,
+	 * we can't just flush the worker.
+	 *
+	 * If this is the case, then the test_and_clear_bit() ensures that
+	 * the worker won't attempt to do anything after the stop.
+	 *
+	 * The trans->restart.mode is a handshake with the opmode, we set
+	 * the context there to ABORT so that when the worker can finally
+	 * acquire the lock in the opmode, the code there won't attempt to
+	 * do any dumps. Since we'd really like to have the dump though,
+	 * also do it inline here (with the opmode locks already held),
+	 * but use a separate mode struct to avoid races.
+	 */
+	if (test_and_clear_bit(STATUS_RESET_PENDING, &trans->status)) {
+		struct iwl_fw_error_dump_mode mode;
+
+		mode = trans->restart.mode;
+		mode.context = IWL_ERR_CONTEXT_FROM_OPMODE;
+		trans->restart.mode.context = IWL_ERR_CONTEXT_ABORT;
+
+		iwl_op_mode_dump_error(trans->op_mode, &mode);
+	}
+
 	if (trans->trans_cfg->gen2)
 		iwl_trans_pcie_gen2_stop_device(trans);
 	else