From 22fbabe82cea7af4127f089b7f3553cd75571d9a Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Thu, 12 Sep 2024 15:30:02 -0700 Subject: [PATCH 1/4] scsi: ufs: core: Improve the struct ufs_hba documentation Make the role of the structure members related to UIC command processing more clear. Reviewed-by: Peter Wang Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20240912223019.3510966-2-bvanassche@acm.org Reviewed-by: Bao D. Nguyen Signed-off-by: Martin K. Petersen --- include/ufs/ufshcd.h | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h index 3f68ae3e4330..a95282b9f743 100644 --- a/include/ufs/ufshcd.h +++ b/include/ufs/ufshcd.h @@ -877,9 +877,10 @@ enum ufshcd_mcq_opr { * @tmf_tag_set: TMF tag set. * @tmf_queue: Used to allocate TMF tags. * @tmf_rqs: array with pointers to TMF requests while these are in progress. - * @active_uic_cmd: handle of active UIC command - * @uic_cmd_mutex: mutex for UIC command - * @uic_async_done: completion used during UIC processing + * @active_uic_cmd: pointer to active UIC command. + * @uic_cmd_mutex: mutex used for serializing UIC command processing. + * @uic_async_done: completion used to wait for power mode or hibernation state + * changes. * @ufshcd_state: UFSHCD state * @eh_flags: Error handling flags * @intr_mask: Interrupt Mask Bits From e31931d646d3bc2223d9a275bac9cdc4963c5bc1 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Thu, 12 Sep 2024 15:30:03 -0700 Subject: [PATCH 2/4] scsi: ufs: core: Make ufshcd_uic_cmd_compl() easier to read Introduce a local variable for the expression hba->active_uic_cmd. Remove superfluous parentheses. No functionality has been changed. Reviewed-by: Bean Huo Reviewed-by: Peter Wang Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20240912223019.3510966-3-bvanassche@acm.org Reviewed-by: Bao D. Nguyen Signed-off-by: Martin K. Petersen --- drivers/ufs/core/ufshcd.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-) diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index 24a32e2fd75e..8212e2d14256 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -5477,31 +5477,30 @@ static bool ufshcd_is_auto_hibern8_error(struct ufs_hba *hba, static irqreturn_t ufshcd_uic_cmd_compl(struct ufs_hba *hba, u32 intr_status) { irqreturn_t retval = IRQ_NONE; + struct uic_command *cmd; spin_lock(hba->host->host_lock); + cmd = hba->active_uic_cmd; if (ufshcd_is_auto_hibern8_error(hba, intr_status)) hba->errors |= (UFSHCD_UIC_HIBERN8_MASK & intr_status); - if ((intr_status & UIC_COMMAND_COMPL) && hba->active_uic_cmd) { - hba->active_uic_cmd->argument2 |= - ufshcd_get_uic_cmd_result(hba); - hba->active_uic_cmd->argument3 = - ufshcd_get_dme_attr_val(hba); + if (intr_status & UIC_COMMAND_COMPL && cmd) { + cmd->argument2 |= ufshcd_get_uic_cmd_result(hba); + cmd->argument3 = ufshcd_get_dme_attr_val(hba); if (!hba->uic_async_done) - hba->active_uic_cmd->cmd_active = 0; - complete(&hba->active_uic_cmd->done); + cmd->cmd_active = 0; + complete(&cmd->done); retval = IRQ_HANDLED; } - if ((intr_status & UFSHCD_UIC_PWR_MASK) && hba->uic_async_done) { - hba->active_uic_cmd->cmd_active = 0; + if (intr_status & UFSHCD_UIC_PWR_MASK && hba->uic_async_done) { + cmd->cmd_active = 0; complete(hba->uic_async_done); retval = IRQ_HANDLED; } if (retval == IRQ_HANDLED) - ufshcd_add_uic_command_trace(hba, hba->active_uic_cmd, - UFS_CMD_COMP); + ufshcd_add_uic_command_trace(hba, cmd, UFS_CMD_COMP); spin_unlock(hba->host->host_lock); return retval; } From fcd8b0450a9acbf3f0e88d749a72ef932df97663 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Thu, 12 Sep 2024 15:30:04 -0700 Subject: [PATCH 3/4] scsi: ufs: core: Make ufshcd_uic_cmd_compl() easier to analyze In ufshcd_uic_cmd_compl(), there is code that dereferences 'cmd' with and without checking the 'cmd' pointer. This confuses static source code analyzers like Coverity and sparse. Since none of the code in ufshcd_uic_cmd_compl() can do anything useful if 'cmd' is NULL, move the 'cmd' test near the start of this function. Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20240912223019.3510966-4-bvanassche@acm.org Reviewed-by: Peter Wang Reviewed-by: Bao D. Nguyen Signed-off-by: Martin K. Petersen --- drivers/ufs/core/ufshcd.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index 8212e2d14256..0c803b6f2221 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -5481,10 +5481,13 @@ static irqreturn_t ufshcd_uic_cmd_compl(struct ufs_hba *hba, u32 intr_status) spin_lock(hba->host->host_lock); cmd = hba->active_uic_cmd; + if (WARN_ON_ONCE(!cmd)) + goto unlock; + if (ufshcd_is_auto_hibern8_error(hba, intr_status)) hba->errors |= (UFSHCD_UIC_HIBERN8_MASK & intr_status); - if (intr_status & UIC_COMMAND_COMPL && cmd) { + if (intr_status & UIC_COMMAND_COMPL) { cmd->argument2 |= ufshcd_get_uic_cmd_result(hba); cmd->argument3 = ufshcd_get_dme_attr_val(hba); if (!hba->uic_async_done) @@ -5501,7 +5504,10 @@ static irqreturn_t ufshcd_uic_cmd_compl(struct ufs_hba *hba, u32 intr_status) if (retval == IRQ_HANDLED) ufshcd_add_uic_command_trace(hba, cmd, UFS_CMD_COMP); + +unlock: spin_unlock(hba->host->host_lock); + return retval; } From b1e8c53749adb795bfb0bf4e2f7836e26684bb90 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Thu, 12 Sep 2024 15:30:05 -0700 Subject: [PATCH 4/4] scsi: ufs: core: Always initialize the UIC done completion Simplify __ufshcd_send_uic_cmd() by always initializing the uic_cmd::done completion. This is fine since the time required to initialize a completion is small compared to the time required to process an UIC command. Reviewed-by: Peter Wang Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20240912223019.3510966-5-bvanassche@acm.org Signed-off-by: Martin K. Petersen --- drivers/ufs/core/ufshcd.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index 0c803b6f2221..d6528048c77f 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -2551,13 +2551,11 @@ ufshcd_wait_for_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd) * __ufshcd_send_uic_cmd - Send UIC commands and retrieve the result * @hba: per adapter instance * @uic_cmd: UIC command - * @completion: initialize the completion only if this is set to true * * Return: 0 only if success. */ static int -__ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd, - bool completion) +__ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd) { lockdep_assert_held(&hba->uic_cmd_mutex); @@ -2567,8 +2565,7 @@ __ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd, return -EIO; } - if (completion) - init_completion(&uic_cmd->done); + init_completion(&uic_cmd->done); uic_cmd->cmd_active = 1; ufshcd_dispatch_uic_cmd(hba, uic_cmd); @@ -2594,7 +2591,7 @@ int ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd) mutex_lock(&hba->uic_cmd_mutex); ufshcd_add_delay_before_dme_cmd(hba); - ret = __ufshcd_send_uic_cmd(hba, uic_cmd, true); + ret = __ufshcd_send_uic_cmd(hba, uic_cmd); if (!ret) ret = ufshcd_wait_for_uic_cmd(hba, uic_cmd); @@ -4289,7 +4286,7 @@ static int ufshcd_uic_pwr_ctrl(struct ufs_hba *hba, struct uic_command *cmd) reenable_intr = true; } spin_unlock_irqrestore(hba->host->host_lock, flags); - ret = __ufshcd_send_uic_cmd(hba, cmd, false); + ret = __ufshcd_send_uic_cmd(hba, cmd); if (ret) { dev_err(hba->dev, "pwr ctrl cmd 0x%x with mode 0x%x uic error %d\n",