> Introduce a function that reports whether or not a controller state change
> is allowed instead of duplicating these checks in every context that
> changes the host controller state. This patch includes a behavior change:
> ufshcd_link_recovery() no longer can change the host controller state from
> UFSHCD_STATE_ERROR into UFSHCD_STATE_RESET.
>
> Cc: Can Guo <cang@xxxxxxxxxxxxxx>
> Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
> ---
> drivers/scsi/ufs/ufshcd.c | 59 ++++++++++++++++++++++++---------------
> 1 file changed, 36 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index c213daec20f7..a10c8ec28468 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -4070,16 +4070,32 @@ static int ufshcd_uic_change_pwr_mode(struct
> ufs_hba *hba, u8 mode)
> return ret;
> }
>
> +static bool ufshcd_set_state(struct ufs_hba *hba, enum ufshcd_state
> new_state)
> +{
> + lockdep_assert_held(hba->host->host_lock);
> +
> + if (old_state != UFSHCD_STATE_ERROR || new_state ==
> UFSHCD_STATE_ERROR)
old_state ?
Thanks,
Avri
> + hba->ufshcd_state = new_state;
> + return true;
> + }
> + return false;
> +}
> +
> int ufshcd_link_recovery(struct ufs_hba *hba)
> {
> int ret;
> unsigned long flags;
> + bool proceed;
>
> spin_lock_irqsave(hba->host->host_lock, flags);
> - hba->ufshcd_state = UFSHCD_STATE_RESET;
> - ufshcd_set_eh_in_progress(hba);
> + proceed = ufshcd_set_state(hba, UFSHCD_STATE_RESET);
> + if (proceed)
> + ufshcd_set_eh_in_progress(hba);
> spin_unlock_irqrestore(hba->host->host_lock, flags);
>
> + if (!proceed)
> + return -EPERM;
> +
> /* Reset the attached device */
> ufshcd_device_reset(hba);
>
> @@ -4087,7 +4103,7 @@ int ufshcd_link_recovery(struct ufs_hba *hba)
>
> spin_lock_irqsave(hba->host->host_lock, flags);
> if (ret)
> - hba->ufshcd_state = UFSHCD_STATE_ERROR;
> + ufshcd_set_state(hba, UFSHCD_STATE_ERROR);
> ufshcd_clear_eh_in_progress(hba);
> spin_unlock_irqrestore(hba->host->host_lock, flags);
>
> @@ -5856,15 +5872,17 @@ static inline bool
> ufshcd_is_saved_err_fatal(struct ufs_hba *hba)
> /* host lock must be held before calling this func */
> static inline void ufshcd_schedule_eh_work(struct ufs_hba *hba)
> {
> - /* handle fatal errors only when link is not in error state */
> - if (hba->ufshcd_state != UFSHCD_STATE_ERROR) {
> - if (hba->force_reset || ufshcd_is_link_broken(hba) ||
> - ufshcd_is_saved_err_fatal(hba))
> - hba->ufshcd_state = UFSHCD_STATE_EH_SCHEDULED_FATAL;
> - else
> - hba->ufshcd_state =
> UFSHCD_STATE_EH_SCHEDULED_NON_FATAL;
> + bool proceed;
> +
> + if (hba->force_reset || ufshcd_is_link_broken(hba) ||
> + ufshcd_is_saved_err_fatal(hba))
> + proceed = ufshcd_set_state(hba,
> + UFSHCD_STATE_EH_SCHEDULED_FATAL);
> + else
> + proceed = ufshcd_set_state(hba,
> + UFSHCD_STATE_EH_SCHEDULED_NON_FATAL);
> + if (proceed)
> queue_work(hba->eh_wq, &hba->eh_work);
> - }
> }
>
> static void ufshcd_clk_scaling_allow(struct ufs_hba *hba, bool allow)
> @@ -6017,8 +6035,7 @@ static void ufshcd_err_handler(struct work_struct
> *work)
> down(&hba->host_sem);
> spin_lock_irqsave(hba->host->host_lock, flags);
> if (ufshcd_err_handling_should_stop(hba)) {
> - if (hba->ufshcd_state != UFSHCD_STATE_ERROR)
> - hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
> + ufshcd_set_state(hba, UFSHCD_STATE_OPERATIONAL);
> spin_unlock_irqrestore(hba->host->host_lock, flags);
> up(&hba->host_sem);
> return;
> @@ -6029,8 +6046,7 @@ static void ufshcd_err_handler(struct work_struct
> *work)
> /* Complete requests that have door-bell cleared by h/w */
> ufshcd_complete_requests(hba);
> spin_lock_irqsave(hba->host->host_lock, flags);
> - if (hba->ufshcd_state != UFSHCD_STATE_ERROR)
> - hba->ufshcd_state = UFSHCD_STATE_RESET;
> + ufshcd_set_state(hba, UFSHCD_STATE_RESET);
> /*
> * A full reset and restore might have happened after preparation
> * is finished, double check whether we should stop.
> @@ -6163,8 +6179,7 @@ static void ufshcd_err_handler(struct work_struct
> *work)
>
> skip_err_handling:
> if (!needs_reset) {
> - if (hba->ufshcd_state == UFSHCD_STATE_RESET)
> - hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
> + ufshcd_set_state(hba, UFSHCD_STATE_OPERATIONAL);
> if (hba->saved_err || hba->saved_uic_err)
> dev_err_ratelimited(hba->dev, "%s: exit: saved_err 0x%x
> saved_uic_err 0x%x",
> __func__, hba->saved_err, hba->saved_uic_err);
> @@ -7135,7 +7150,7 @@ static int ufshcd_reset_and_restore(struct ufs_hba
> *hba)
> */
> scsi_report_bus_reset(hba->host, 0);
> if (err) {
> - hba->ufshcd_state = UFSHCD_STATE_ERROR;
> + ufshcd_set_state(hba, UFSHCD_STATE_ERROR);
> hba->saved_err |= saved_err;
> hba->saved_uic_err |= saved_uic_err;
> }
> @@ -7951,7 +7966,7 @@ static int ufshcd_probe_hba(struct ufs_hba *hba,
> bool init_dev_params)
> unsigned long flags;
> ktime_t start = ktime_get();
>
> - hba->ufshcd_state = UFSHCD_STATE_RESET;
> + ufshcd_set_state(hba, UFSHCD_STATE_RESET);
>
> ret = ufshcd_link_startup(hba);
> if (ret)
> @@ -8024,10 +8039,8 @@ static int ufshcd_probe_hba(struct ufs_hba *hba,
> bool init_dev_params)
>
> out:
> spin_lock_irqsave(hba->host->host_lock, flags);
> - if (ret)
> - hba->ufshcd_state = UFSHCD_STATE_ERROR;
> - else if (hba->ufshcd_state == UFSHCD_STATE_RESET)
> - hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL;
> + ufshcd_set_state(hba, ret ? UFSHCD_STATE_ERROR :
> + UFSHCD_STATE_OPERATIONAL);
> spin_unlock_irqrestore(hba->host->host_lock, flags);
>
> trace_ufshcd_init(dev_name(hba->dev), ret,
