[PATCH 11/21] ufs: Verify UIC locking requirements at runtime
From: Bart Van Assche <bvanassche@acm.org>
Date: 2021-07-01 21:13:20
Subsystem:
scsi subsystem, the rest · Maintainers:
"James E.J. Bottomley", "Martin K. Petersen", Linus Torvalds
Instead of documenting the locking requirements of the UIC code as comments, use lockdep_assert_held() such that lockdep verifies the lockdep requirements at runtime if lockdep is enabled. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Stanley Chu <redacted> Cc: Can Guo <redacted> Cc: Asutosh Das <redacted> Cc: Avri Altman <avri.altman@wdc.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> --- drivers/scsi/ufs/ufshcd.c | 16 +++++++++------- drivers/scsi/ufs/ufshcd.h | 2 +- 2 files changed, 10 insertions(+), 8 deletions(-)
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 2e6aa614e3f5..1262f1a63e0b 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c@@ -2242,15 +2242,15 @@ static inline u8 ufshcd_get_upmcrs(struct ufs_hba *hba) } /** - * ufshcd_dispatch_uic_cmd - Dispatch UIC commands to unipro layers + * ufshcd_dispatch_uic_cmd - Dispatch an UIC command to the Unipro layer * @hba: per adapter instance * @uic_cmd: UIC command - * - * Mutex must be held. */ static inline void ufshcd_dispatch_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd) { + lockdep_assert_held(&hba->uic_cmd_mutex); + WARN_ON(hba->active_uic_cmd); hba->active_uic_cmd = uic_cmd;
@@ -2268,11 +2268,10 @@ ufshcd_dispatch_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd) } /** - * ufshcd_wait_for_uic_cmd - Wait complectioin of UIC command + * ufshcd_wait_for_uic_cmd - Wait for completion of an UIC command * @hba: per adapter instance * @uic_cmd: UIC command * - * Must be called with mutex held. * Returns 0 only if success. */ static int
@@ -2281,6 +2280,8 @@ ufshcd_wait_for_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd) int ret; unsigned long flags; + lockdep_assert_held(&hba->uic_cmd_mutex); + if (wait_for_completion_timeout(&uic_cmd->done, msecs_to_jiffies(UIC_CMD_TIMEOUT))) { ret = uic_cmd->argument2 & MASK_UIC_COMMAND_RESULT;
@@ -2310,14 +2311,15 @@ ufshcd_wait_for_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd) * @uic_cmd: UIC command * @completion: initialize the completion only if this is set to true * - * Identical to ufshcd_send_uic_cmd() expect mutex. Must be called - * with mutex held and host_lock locked. * Returns 0 only if success. */ static int __ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd, bool completion) { + lockdep_assert_held(&hba->uic_cmd_mutex); + lockdep_assert_held(hba->host->host_lock); + if (!ufshcd_ready_for_uic_cmd(hba)) { dev_err(hba->dev, "Controller not ready to accept UIC commands\n");
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index 79f6c261dfff..0dfb5e97ec0d 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h@@ -683,7 +683,7 @@ struct ufs_hba_monitor { * @priv: pointer to variant specific private data * @irq: Irq number of the controller * @active_uic_cmd: handle of active UIC command - * @uic_cmd_mutex: mutex for uic command + * @uic_cmd_mutex: mutex for UIC command * @tmf_tag_set: TMF tag set. * @tmf_queue: Used to allocate TMF tags. * @pwr_done: completion for power mode change