This patch attempts to fix a deadlock in ufs while sending SSU.
Recently, blk_queue_enter() added a check to not process requests if the
queue is suspended. That leads to a resume of the associated device which
is suspended. In ufs, that device is ufs device wlun and it's parent is
ufs_hba. This resume tries to resume ufs device wlun which in turn tries
to resume ufs_hba, which is already in the process of suspending, thus
causing a deadlock.
This patch takes care of:
* Suspending the ufs device lun only after all other luns are suspended
* Sending SSU during ufs device wlun suspend
* Clearing uac for rpmb and ufs device wlun
* Not sending commands to the device during host suspend
v14 -> v15:
- Rebased on 5.13/scsi-staging
v13 -> v14:
- Addressed Adrian's comments
* Rebased it on top of scsi-next
* Added scsi_autopm_[get/put] to ufs_debugfs[get/put]_user_access()
* Resume the device in ufshcd_remove()
* Unregister ufs_rpmb_wlun before ufs_dev_wlun
* hba->shutting_down moved to ufshcd_wl_shutdown()
v12 -> v13:
- Addressed Adrian's comments
* Paired pm_runtime_get_noresume() with pm_runtime_put()
* no rpm_autosuspend for ufs device wlun
* Moved runtime-pm init functionality to ufshcd_wl_probe()
- Addressed Bart's comments
* Expanded abbrevs in commit message
v11 -> v12:
- Addressed Adrian's comments
* Fixed ahit for Mediatek driver
* Fixed error handling in ufshcd_core_init()
* Tested this patch and the issue is still seen.
v10 -> v11:
- Fixed supplier suspending before consumer race
- Addressed Adrian's comments
* Added proper resume/suspend cb to ufshcd_auto_hibern8_update()
* Cosmetic changes to ufshcd-pci.c
* Cleaned up ufshcd_system_suspend()
* Added ufshcd_debugfs_eh_exit to ufshcd_core_init()
v9 -> v10:
- Addressed Adrian's comments
* Moved suspend/resume vops to __ufshcd_wl_[suspend/resume]()
* Added correct resume in ufs_bsg
v8 -> v9:
- Addressed Adrian's comments
* Moved link transition to __ufshcd_wl_[suspend/resume]()
* Fixed the other minor comments
v7 -> v8:
- Addressed Adrian's comments
* Removed separate autosuspend delay for ufs-device lun
* Fixed the ee handler getting scheduled during pm
* Always runtime resume in suspend_prepare()
* Added CONFIG_PM_SLEEP where needed
v6 -> v7:
* Resume the ufs device before shutting it down
v5 -> v6:
- Addressed Adrian's comments
* Added complete() cb
* Added suspend_prepare() and complete() to all drivers
* Moved suspend_prepare() and complete() to ufshcd
* .poweroff() uses ufhcd_wl_poweroff()
* Removed several forward declarations
* Moved scsi_register_driver() to ufshcd_core_init()
v4 -> v5:
- Addressed Adrian's comments
* Used the rpmb driver contributed by Adrian
* Runtime-resume the ufs device during suspend to honor spm-lvl
* Unregister the scsi_driver in ufshcd_remove()
* Currently shutdown() puts the ufs device to power-down mode
so, just removed ufshcd_pci_poweroff()
* Quiesce the scsi device during shutdown instead of remove
v3 RFC -> v4:
- Addressed Bart's comments
* Except that I didn't get any checkpatch failures
- Addressed Avri's comments
- Addressed Adrian's comments
* Added a check for deepsleep power mode
* Removed a couple of forward declarations
* Didn't separate the scsi drivers because in rpmb case it just sends uac
in resume and it seemed pretty neat to me.
- Added sysfs changes to resume the devices before accessing
Asutosh Das (2):
scsi: ufs: Enable power management for wlun
ufs: sysfs: Resume the proper scsi device
drivers/scsi/ufs/cdns-pltfrm.c | 2 +
drivers/scsi/ufs/tc-dwc-g210-pci.c | 2 +
drivers/scsi/ufs/ufs-debugfs.c | 2 +-
drivers/scsi/ufs/ufs-debugfs.h | 2 +-
drivers/scsi/ufs/ufs-exynos.c | 2 +
drivers/scsi/ufs/ufs-hisi.c | 2 +
drivers/scsi/ufs/ufs-mediatek.c | 12 +-
drivers/scsi/ufs/ufs-qcom.c | 2 +
drivers/scsi/ufs/ufs-sysfs.c | 30 +-
drivers/scsi/ufs/ufs_bsg.c | 6 +-
drivers/scsi/ufs/ufshcd-pci.c | 36 +--
drivers/scsi/ufs/ufshcd.c | 636 ++++++++++++++++++++++++++-----------
drivers/scsi/ufs/ufshcd.h | 6 +
include/trace/events/ufs.h | 20 ++
14 files changed, 519 insertions(+), 241 deletions(-)
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