Merge "scsi: ufs: fix race between hibern8 failure recovery and error handler" (129e6b5b) · Commits · e / devices / android_kernel_xiaomi_markw

drivers/scsi/ufs/ufs-debugfs.c

+8 −2

Original line number	Diff line number	Diff line
		@@ -1412,8 +1412,10 @@ static ssize_t ufsdbg_reset_controller_write(struct file *filp,
		struct ufs_hba *hba = filp->f_mapping->host->i_private;
		unsigned long flags;

		spin_lock_irqsave(hba->host->host_lock, flags);
		pm_runtime_get_sync(hba->dev);
		ufshcd_hold(hba, false);

		spin_lock_irqsave(hba->host->host_lock, flags);
		/*
		* simulating a dummy error in order to "convince"
		* eh_work to actually reset the controller
		@@ -1421,9 +1423,13 @@ static ssize_t ufsdbg_reset_controller_write(struct file *filp,
		hba->saved_err \|= INT_FATAL_ERRORS;
		hba->silence_err_logs = true;
		schedule_work(&hba->eh_work);

		spin_unlock_irqrestore(hba->host->host_lock, flags);

		flush_work(&hba->eh_work);

		ufshcd_release(hba, false);
		pm_runtime_put_sync(hba->dev);

		return cnt;
		}

drivers/scsi/ufs/ufshcd.c

+82 −53

Original line number	Diff line number	Diff line
		@@ -2576,6 +2576,13 @@ static int ufshcd_queuecommand(struct Scsi_Host host, struct scsi_cmnd cmd)
		return SCSI_MLQUEUE_HOST_BUSY;

		spin_lock_irqsave(hba->host->host_lock, flags);

		/* if error handling is in progress, return host busy */
		if (ufshcd_eh_in_progress(hba)) {
		err = SCSI_MLQUEUE_HOST_BUSY;
		goto out_unlock;
		}

		switch (hba->ufshcd_state) {
		case UFSHCD_STATE_OPERATIONAL:
		break;
		@@ -2593,13 +2600,6 @@ static int ufshcd_queuecommand(struct Scsi_Host host, struct scsi_cmnd cmd)
		cmd->scsi_done(cmd);
		goto out_unlock;
		}

		/* if error handling is in progress, don't issue commands */
		if (ufshcd_eh_in_progress(hba)) {
		set_host_byte(cmd, DID_ERROR);
		cmd->scsi_done(cmd);
		goto out_unlock;
		}
		spin_unlock_irqrestore(hba->host->host_lock, flags);

		hba->req_abort_count = 0;
		@@ -3972,31 +3972,49 @@ out:

		static int ufshcd_link_recovery(struct ufs_hba *hba)
		{
		int ret;
		int ret = 0;
		unsigned long flags;

		/*
		* Check if there is any race with fatal error handling.
		* If so, wait for it to complete. Even though fatal error
		* handling does reset and restore in some cases, don't assume
		* anything out of it. We are just avoiding race here.
		*/
		do {
		spin_lock_irqsave(hba->host->host_lock, flags);
		hba->ufshcd_state = UFSHCD_STATE_RESET;
		ufshcd_set_eh_in_progress(hba);
		if (!(work_pending(&hba->eh_work) \|\|
		hba->ufshcd_state == UFSHCD_STATE_RESET))
		break;
		spin_unlock_irqrestore(hba->host->host_lock, flags);
		dev_dbg(hba->dev, "%s: reset in progress\n", __func__);
		flush_work(&hba->eh_work);
		} while (1);

		ret = ufshcd_vops_full_reset(hba);
		if (ret)
		dev_warn(hba->dev,
		"full reset returned %d, trying to recover the link\n",
		ret);

		ret = ufshcd_host_reset_and_restore(hba);

		spin_lock_irqsave(hba->host->host_lock, flags);
		if (ret)
		/*
		* we don't know if previous reset had really reset the host controller
		* or not. So let's force reset here to be sure.
		*/
		hba->ufshcd_state = UFSHCD_STATE_ERROR;
		ufshcd_clear_eh_in_progress(hba);
		hba->force_host_reset = true;
		schedule_work(&hba->eh_work);

		/* wait for the reset work to finish */
		do {
		if (!(work_pending(&hba->eh_work) \|\|
		hba->ufshcd_state == UFSHCD_STATE_RESET))
		break;
		spin_unlock_irqrestore(hba->host->host_lock, flags);
		dev_dbg(hba->dev, "%s: reset in progress\n", __func__);
		flush_work(&hba->eh_work);
		spin_lock_irqsave(hba->host->host_lock, flags);
		} while (1);

		if (ret)
		dev_err(hba->dev, "%s: link recovery failed, err %d",
		__func__, ret);
		if (!((hba->ufshcd_state == UFSHCD_STATE_OPERATIONAL) &&
		ufshcd_is_link_active(hba)))
		ret = -ENOLINK;
		spin_unlock_irqrestore(hba->host->host_lock, flags);

		return ret;
		}
		@@ -4020,8 +4038,7 @@ static int __ufshcd_uic_hibern8_enter(struct ufs_hba *hba)
		* If link recovery fails then return error so that caller
		* don't retry the hibern8 enter again.
		*/
		if (ufshcd_link_recovery(hba))
		ret = -ENOLINK;
		ret = ufshcd_link_recovery(hba);
		} else {
		dev_dbg(hba->dev, "%s: Hibern8 Enter at %lld us", __func__,
		ktime_to_us(ktime_get()));
		@@ -5553,11 +5570,9 @@ static void ufshcd_err_handler(struct work_struct *work)

		hba = container_of(work, struct ufs_hba, eh_work);

		spin_lock_irqsave(hba->host->host_lock, flags);
		ufsdbg_set_err_state(hba);
		pm_runtime_get_sync(hba->dev);
		ufshcd_hold_all(hba);

		spin_lock_irqsave(hba->host->host_lock, flags);
		if (hba->ufshcd_state == UFSHCD_STATE_RESET)
		goto out;

		@@ -5593,7 +5608,8 @@ static void ufshcd_err_handler(struct work_struct *work)
		}
		}

		if ((hba->saved_err & INT_FATAL_ERRORS) \|\| hba->saved_ce_err \|\|
		if ((hba->saved_err & INT_FATAL_ERRORS)
		\|\| hba->saved_ce_err \|\| hba->force_host_reset \|\|
		((hba->saved_err & UIC_ERROR) &&
		(hba->saved_uic_err & (UFSHCD_UIC_DL_PA_INIT_ERROR \|
		UFSHCD_UIC_DL_NAC_RECEIVED_ERROR \|
		@@ -5681,6 +5697,7 @@ skip_pending_xfer_clear:
		hba->saved_err = 0;
		hba->saved_uic_err = 0;
		hba->saved_ce_err = 0;
		hba->force_host_reset = false;
		}

		skip_err_handling:
		@@ -5692,12 +5709,9 @@ skip_err_handling:
		}

		hba->silence_err_logs = false;
		ufshcd_clear_eh_in_progress(hba);
		out:
		ufshcd_clear_eh_in_progress(hba);
		spin_unlock_irqrestore(hba->host->host_lock, flags);
		ufshcd_scsi_unblock_requests(hba);
		ufshcd_release_all(hba);
		pm_runtime_put_sync(hba->dev);
		}

		static void ufshcd_update_uic_reg_hist(struct ufs_uic_err_reg_hist *reg_hist,
		@@ -5798,8 +5812,11 @@ static void ufshcd_check_errors(struct ufs_hba *hba)

		/* handle fatal errors only when link is functional */
		if (hba->ufshcd_state == UFSHCD_STATE_OPERATIONAL) {
		/* block commands from scsi mid-layer */
		__ufshcd_scsi_block_requests(hba);
		/*
		* Set error handling in progress flag early so that we
		* don't issue new requests any more.
		*/
		ufshcd_set_eh_in_progress(hba);

		hba->ufshcd_state = UFSHCD_STATE_ERROR;
		schedule_work(&hba->eh_work);
		@@ -6303,6 +6320,11 @@ static int ufshcd_reset_and_restore(struct ufs_hba *hba)
		int retries = MAX_HOST_RESET_RETRIES;

		do {
		err = ufshcd_vops_full_reset(hba);
		if (err)
		dev_warn(hba->dev, "%s: full reset returned %d\n",
		__func__, err);

		err = ufshcd_host_reset_and_restore(hba);
		} while (err && --retries);

		@@ -6326,13 +6348,12 @@ static int ufshcd_reset_and_restore(struct ufs_hba *hba)
		*/
		static int ufshcd_eh_host_reset_handler(struct scsi_cmnd *cmd)
		{
		int err;
		int err = SUCCESS;
		unsigned long flags;
		struct ufs_hba *hba;

		hba = shost_priv(cmd->device->host);

		ufshcd_hold_all(hba);
		/*
		* Check if there is any race with fatal error handling.
		* If so, wait for it to complete. Even though fatal error
		@@ -6345,29 +6366,37 @@ static int ufshcd_eh_host_reset_handler(struct scsi_cmnd *cmd)
		hba->ufshcd_state == UFSHCD_STATE_RESET))
		break;
		spin_unlock_irqrestore(hba->host->host_lock, flags);
		dev_dbg(hba->dev, "%s: reset in progress\n", __func__);
		dev_err(hba->dev, "%s: reset in progress - 1\n", __func__);
		flush_work(&hba->eh_work);
		} while (1);

		hba->ufshcd_state = UFSHCD_STATE_RESET;
		ufshcd_set_eh_in_progress(hba);
		spin_unlock_irqrestore(hba->host->host_lock, flags);

		ufshcd_update_error_stats(hba, UFS_ERR_EH);
		err = ufshcd_reset_and_restore(hba);
		/*
		* we don't know if previous reset had really reset the host controller
		* or not. So let's force reset here to be sure.
		*/
		hba->ufshcd_state = UFSHCD_STATE_ERROR;
		hba->force_host_reset = true;
		schedule_work(&hba->eh_work);

		/* wait for the reset work to finish */
		do {
		if (!(work_pending(&hba->eh_work) \|\|
		hba->ufshcd_state == UFSHCD_STATE_RESET))
		break;
		spin_unlock_irqrestore(hba->host->host_lock, flags);
		dev_err(hba->dev, "%s: reset in progress - 2\n", __func__);
		flush_work(&hba->eh_work);
		spin_lock_irqsave(hba->host->host_lock, flags);
		if (!err) {
		err = SUCCESS;
		hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
		} else {
		} while (1);

		if (!((hba->ufshcd_state == UFSHCD_STATE_OPERATIONAL) &&
		ufshcd_is_link_active(hba))) {
		err = FAILED;
		hba->ufshcd_state = UFSHCD_STATE_ERROR;
		}
		ufshcd_clear_eh_in_progress(hba);

		spin_unlock_irqrestore(hba->host->host_lock, flags);

		ufshcd_release_all(hba);
		return err;
		}

drivers/scsi/ufs/ufshcd.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -807,6 +807,7 @@ struct ufs_hba {
		u32 saved_uic_err;
		u32 saved_ce_err;
		bool silence_err_logs;
		bool force_host_reset;

		/* Device management request data */
		struct ufs_dev_cmd dev_cmd;