From patchwork Tue Sep 22 05:32:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Can Guo X-Patchwork-Id: 11791541 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5279D112C for ; Tue, 22 Sep 2020 05:38:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4065523AA1 for ; Tue, 22 Sep 2020 05:38:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728432AbgIVFin (ORCPT ); Tue, 22 Sep 2020 01:38:43 -0400 Received: from labrats.qualcomm.com ([199.106.110.90]:1081 "EHLO labrats.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726497AbgIVFin (ORCPT ); Tue, 22 Sep 2020 01:38:43 -0400 X-Greylist: delayed 364 seconds by postgrey-1.27 at vger.kernel.org; Tue, 22 Sep 2020 01:38:41 EDT IronPort-SDR: GlTueeVaXkGCNQPtWgEIE6UuGTtkusP4llbyBUbi4M9vfcuv70AQI5RmLwHJNfwpJ3Vv3UBGpD iDjuz9RyZC7jUlIfWBkhfhMAONVnYEs0VTlVRwWIiUj/+ASCvpe9Pi6Qq1i6x8Ind13MvBaSGE DHFMFl5MeFxauCNHAk4R1cS/FUx4NCaKG3ADWxl+d2/kX7HvKtF+iEB3POSG/v4zkt/Yctf7ZD TaNd2SpMNUYvDBvPYV6DVU322n1vJK8UmzKybBmxtXP6EfGwL5XcBuQQrjLnSmTuw8hXMWfvBz FRM= X-IronPort-AV: E=Sophos;i="5.77,289,1596524400"; d="scan'208";a="47332957" Received: from unknown (HELO ironmsg03-sd.qualcomm.com) ([10.53.140.143]) by labrats.qualcomm.com with ESMTP; 21 Sep 2020 22:32:37 -0700 Received: from wsp769891wss.qualcomm.com (HELO stor-presley.qualcomm.com) ([192.168.140.85]) by ironmsg03-sd.qualcomm.com with ESMTP; 21 Sep 2020 22:32:36 -0700 Received: by stor-presley.qualcomm.com (Postfix, from userid 359480) id 9A23321547; Mon, 21 Sep 2020 22:32:36 -0700 (PDT) From: Can Guo To: asutoshd@codeaurora.org, nguyenb@codeaurora.org, hongwus@codeaurora.org, rnayak@codeaurora.org, linux-scsi@vger.kernel.org, kernel-team@android.com, saravanak@google.com, salyzyn@google.com, cang@codeaurora.org Cc: Alim Akhtar , Avri Altman , "James E.J. Bottomley" , "Martin K. Petersen" , Stanley Chu , Bean Huo , Bart Van Assche , Satya Tangirala , linux-kernel@vger.kernel.org (open list) Subject: [PATCH v1 1/2] scsi: ufs: Serialize eh_work with system PM events and async scan Date: Mon, 21 Sep 2020 22:32:25 -0700 Message-Id: <1600752747-31881-2-git-send-email-cang@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1600752747-31881-1-git-send-email-cang@codeaurora.org> References: <1600752747-31881-1-git-send-email-cang@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Serialize eh_work with system PM events and async scan to make sure eh_work does not run in parallel with them. Change-Id: I33012c68e2ea443950313c59a4a46ad88cf3c82d Signed-off-by: Can Guo --- drivers/scsi/ufs/ufshcd.c | 64 +++++++++++++++++++++++++++++------------------ drivers/scsi/ufs/ufshcd.h | 1 + 2 files changed, 41 insertions(+), 24 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 1d8134e..7e764e8 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -5597,7 +5597,9 @@ static inline void ufshcd_schedule_eh_work(struct ufs_hba *hba) static void ufshcd_err_handling_prepare(struct ufs_hba *hba) { pm_runtime_get_sync(hba->dev); - if (pm_runtime_suspended(hba->dev)) { + if (pm_runtime_status_suspended(hba->dev) || hba->is_sys_suspended) { + enum ufs_pm_op pm_op; + /* * Don't assume anything of pm_runtime_get_sync(), if * resume fails, irq and clocks can be OFF, and powers @@ -5612,7 +5614,8 @@ static void ufshcd_err_handling_prepare(struct ufs_hba *hba) if (!ufshcd_is_clkgating_allowed(hba)) ufshcd_setup_clocks(hba, true); ufshcd_release(hba); - ufshcd_vops_resume(hba, UFS_RUNTIME_PM); + pm_op = hba->is_sys_suspended ? UFS_RUNTIME_PM : UFS_SYSTEM_PM; + ufshcd_vops_resume(hba, pm_op); } else { ufshcd_hold(hba, false); if (hba->clk_scaling.is_allowed) { @@ -5633,7 +5636,7 @@ static void ufshcd_err_handling_unprepare(struct ufs_hba *hba) static inline bool ufshcd_err_handling_should_stop(struct ufs_hba *hba) { - return (hba->ufshcd_state == UFSHCD_STATE_ERROR || + return (!hba->is_powered || hba->ufshcd_state == UFSHCD_STATE_ERROR || (!(hba->saved_err || hba->saved_uic_err || hba->force_reset || ufshcd_is_link_broken(hba)))); } @@ -5646,6 +5649,7 @@ static void ufshcd_recover_pm_error(struct ufs_hba *hba) struct request_queue *q; int ret; + hba->is_sys_suspended = false; /* * Set RPM status of hba device to RPM_ACTIVE, * this also clears its runtime error. @@ -5704,11 +5708,13 @@ static void ufshcd_err_handler(struct work_struct *work) hba = container_of(work, struct ufs_hba, eh_work); + down(&hba->eh_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; spin_unlock_irqrestore(hba->host->host_lock, flags); + up(&hba->eh_sem); return; } ufshcd_set_eh_in_progress(hba); @@ -5716,20 +5722,18 @@ static void ufshcd_err_handler(struct work_struct *work) ufshcd_err_handling_prepare(hba); spin_lock_irqsave(hba->host->host_lock, flags); ufshcd_scsi_block_requests(hba); - /* - * A full reset and restore might have happened after preparation - * is finished, double check whether we should stop. - */ - if (ufshcd_err_handling_should_stop(hba)) { - if (hba->ufshcd_state != UFSHCD_STATE_ERROR) - hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL; - goto out; - } hba->ufshcd_state = UFSHCD_STATE_RESET; /* Complete requests that have door-bell cleared by h/w */ ufshcd_complete_requests(hba); + /* + * A full reset and restore might have happened after preparation + * is finished, double check whether we should stop. + */ + if (ufshcd_err_handling_should_stop(hba)) + goto skip_err_handling; + if (hba->dev_quirks & UFS_DEVICE_QUIRK_RECOVERY_FROM_DL_NAC_ERRORS) { bool ret; @@ -5737,17 +5741,10 @@ static void ufshcd_err_handler(struct work_struct *work) /* release the lock as ufshcd_quirk_dl_nac_errors() may sleep */ ret = ufshcd_quirk_dl_nac_errors(hba); spin_lock_irqsave(hba->host->host_lock, flags); - if (!ret && !hba->force_reset && ufshcd_is_link_active(hba)) + if (!ret && ufshcd_err_handling_should_stop(hba)) goto skip_err_handling; } - if (hba->force_reset || ufshcd_is_link_broken(hba) || - ufshcd_is_saved_err_fatal(hba) || - ((hba->saved_err & UIC_ERROR) && - (hba->saved_uic_err & (UFSHCD_UIC_DL_NAC_RECEIVED_ERROR | - UFSHCD_UIC_DL_TCx_REPLAY_ERROR)))) - needs_reset = true; - if ((hba->saved_err & (INT_FATAL_ERRORS | UFSHCD_UIC_HIBERN8_MASK)) || (hba->saved_uic_err && (hba->saved_uic_err != UFSHCD_UIC_PA_GENERIC_ERROR))) { @@ -5767,8 +5764,14 @@ static void ufshcd_err_handler(struct work_struct *work) * transfers forcefully because they will get cleared during * host reset and restore */ - if (needs_reset) + if (hba->force_reset || ufshcd_is_link_broken(hba) || + ufshcd_is_saved_err_fatal(hba) || + ((hba->saved_err & UIC_ERROR) && + (hba->saved_uic_err & (UFSHCD_UIC_DL_NAC_RECEIVED_ERROR | + UFSHCD_UIC_DL_TCx_REPLAY_ERROR)))) { + needs_reset = true; goto do_reset; + } /* * If LINERESET was caught, UFS might have been put to PWM mode, @@ -5876,12 +5879,11 @@ static void ufshcd_err_handler(struct work_struct *work) dev_err_ratelimited(hba->dev, "%s: exit: saved_err 0x%x saved_uic_err 0x%x", __func__, hba->saved_err, hba->saved_uic_err); } - -out: ufshcd_clear_eh_in_progress(hba); spin_unlock_irqrestore(hba->host->host_lock, flags); ufshcd_scsi_unblock_requests(hba); ufshcd_err_handling_unprepare(hba); + up(&hba->eh_sem); } /** @@ -6856,6 +6858,7 @@ 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; hba->saved_err |= saved_err; hba->saved_uic_err |= saved_uic_err; } @@ -7704,8 +7707,10 @@ static void ufshcd_async_scan(void *data, async_cookie_t cookie) struct ufs_hba *hba = (struct ufs_hba *)data; int ret; + down(&hba->eh_sem); /* Initialize hba, detect and initialize UFS device */ ret = ufshcd_probe_hba(hba, true); + up(&hba->eh_sem); if (ret) goto out; @@ -8718,6 +8723,7 @@ int ufshcd_system_suspend(struct ufs_hba *hba) int ret = 0; ktime_t start = ktime_get(); + down(&hba->eh_sem); if (!hba || !hba->is_powered) return 0; @@ -8748,6 +8754,8 @@ int ufshcd_system_suspend(struct ufs_hba *hba) hba->curr_dev_pwr_mode, hba->uic_link_state); if (!ret) hba->is_sys_suspended = true; + else + up(&hba->eh_sem); return ret; } EXPORT_SYMBOL(ufshcd_system_suspend); @@ -8764,8 +8772,10 @@ int ufshcd_system_resume(struct ufs_hba *hba) int ret = 0; ktime_t start = ktime_get(); - if (!hba) + if (!hba) { + up(&hba->eh_sem); return -EINVAL; + } if (!hba->is_powered || pm_runtime_suspended(hba->dev)) /* @@ -8781,6 +8791,7 @@ int ufshcd_system_resume(struct ufs_hba *hba) hba->curr_dev_pwr_mode, hba->uic_link_state); if (!ret) hba->is_sys_suspended = false; + up(&hba->eh_sem); return ret; } EXPORT_SYMBOL(ufshcd_system_resume); @@ -8872,6 +8883,7 @@ int ufshcd_shutdown(struct ufs_hba *hba) { int ret = 0; + down(&hba->eh_sem); if (!hba->is_powered) goto out; @@ -8888,6 +8900,8 @@ int ufshcd_shutdown(struct ufs_hba *hba) out: if (ret) dev_err(hba->dev, "%s failed, err %d\n", __func__, ret); + hba->is_powered = false; + up(&hba->eh_sem); /* allow force shutdown even in case of errors */ return 0; } @@ -9082,6 +9096,8 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) INIT_WORK(&hba->eh_work, ufshcd_err_handler); INIT_WORK(&hba->eeh_work, ufshcd_exception_event_handler); + sema_init(&hba->eh_sem, 1); + /* Initialize UIC command mutex */ mutex_init(&hba->uic_cmd_mutex); diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index 47eb143..1e680bf 100644 --- a/drivers/scsi/ufs/ufshcd.h +++ b/drivers/scsi/ufs/ufshcd.h @@ -728,6 +728,7 @@ struct ufs_hba { u32 intr_mask; u16 ee_ctrl_mask; bool is_powered; + struct semaphore eh_sem; /* Work Queues */ struct workqueue_struct *eh_wq; From patchwork Tue Sep 22 05:32:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Can Guo X-Patchwork-Id: 11791543 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 69B35139A for ; Tue, 22 Sep 2020 05:38:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5472B23A9F for ; Tue, 22 Sep 2020 05:38:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728656AbgIVFiv (ORCPT ); Tue, 22 Sep 2020 01:38:51 -0400 Received: from labrats.qualcomm.com ([199.106.110.90]:23288 "EHLO labrats.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726497AbgIVFiu (ORCPT ); Tue, 22 Sep 2020 01:38:50 -0400 IronPort-SDR: YRS8wZcoDpLrUC8CTHsFfZfm6FCCD55nYX9x4kcPRAuKnJkS8nf92nwBtF367V9ZI6X/eIR52h M7HN6DBtbNnB3wq3Yba93pXaiEm58kXks6RtlZBqEjvfMKuVbd0BdX4EqNstgYK9+P/URpjpTZ rUqKxlTjSfM5Lge17CrNi3n/nGp1I1NKS1ZrMzzXlr07xOlg9QKRks8q4u7qEjF9iWbnT14dfi ZbwPxs29RtNaF6DU4t6XGSiDo8qhFMia1omLdmCdDp8WVfMZKDdu2gq4XqAir8jiaXR4jRB7cq xCM= X-IronPort-AV: E=Sophos;i="5.77,289,1596524400"; d="scan'208";a="47332958" Received: from unknown (HELO ironmsg03-sd.qualcomm.com) ([10.53.140.143]) by labrats.qualcomm.com with ESMTP; 21 Sep 2020 22:32:46 -0700 Received: from wsp769891wss.qualcomm.com (HELO stor-presley.qualcomm.com) ([192.168.140.85]) by ironmsg03-sd.qualcomm.com with ESMTP; 21 Sep 2020 22:32:45 -0700 Received: by stor-presley.qualcomm.com (Postfix, from userid 359480) id EB2A621547; Mon, 21 Sep 2020 22:32:43 -0700 (PDT) From: Can Guo To: asutoshd@codeaurora.org, nguyenb@codeaurora.org, hongwus@codeaurora.org, rnayak@codeaurora.org, linux-scsi@vger.kernel.org, kernel-team@android.com, saravanak@google.com, salyzyn@google.com, cang@codeaurora.org Cc: Alim Akhtar , Avri Altman , "James E.J. Bottomley" , "Martin K. Petersen" , Stanley Chu , Bean Huo , Bart Van Assche , Satya Tangirala , linux-kernel@vger.kernel.org (open list) Subject: [PATCH v1 2/2] scsi: ufs: Fix a racing problem between ufshcd_abort and eh_work Date: Mon, 21 Sep 2020 22:32:26 -0700 Message-Id: <1600752747-31881-3-git-send-email-cang@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1600752747-31881-1-git-send-email-cang@codeaurora.org> References: <1600752747-31881-1-git-send-email-cang@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org In current task abort routine, if task abort happens to the device W-LU, the code directly jumps to ufshcd_eh_host_reset_handler() to perform a full reset and restore then returns FAIL or SUCCESS. Commands sent to the device W-LU are most likely the SSU cmds sent during UFS PM operations. If such SSU cmd enters task abort routine, when ufshcd_eh_host_reset_handler() flushes eh_work, there will be racing because err_handler is serialized with any PM operations. Since the main idea of aborting one cmd to the device W-LU is to perform a full reset and restore, in order to resolve the racing problem, we merely clean up the lrb taken by this cmd, queue the eh_work and abort the cmd. Since the cmd has been aborted, the PM operation which sends the cmd simply errors out, thus err_handler will not be blocked by ongoing PM operations and err_handler can also recover PM error if any, which comes as another benefit of this change. Because such cmd is aborted even before it is actually cleared from HW, set the lrb->in_use flag to prevent subsequent cmds, including SCSI cmds and dev cmds, from taking the lrb released by this cmd. Flag lrb->in_use shall evetually be cleared in __ufshcd_transfer_req_compl() invoked by the full reset and restore from err_handler. Signed-off-by: Can Guo --- drivers/scsi/ufs/ufshcd.c | 58 +++++++++++++++++++++++++++++++++++++---------- drivers/scsi/ufs/ufshcd.h | 2 ++ 2 files changed, 48 insertions(+), 12 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 7e764e8..e4cb994 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -2539,6 +2539,14 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd) (hba->clk_gating.state != CLKS_ON)); lrbp = &hba->lrb[tag]; + if (unlikely(lrbp->in_use)) { + if (hba->pm_op_in_progress) + set_host_byte(cmd, DID_BAD_TARGET); + else + err = SCSI_MLQUEUE_HOST_BUSY; + ufshcd_release(hba); + goto out; + } WARN_ON(lrbp->cmd); lrbp->cmd = cmd; @@ -2781,6 +2789,11 @@ static int ufshcd_exec_dev_cmd(struct ufs_hba *hba, init_completion(&wait); lrbp = &hba->lrb[tag]; + if (unlikely(lrbp->in_use)) { + err = -EBUSY; + goto out; + } + WARN_ON(lrbp->cmd); err = ufshcd_compose_dev_cmd(hba, lrbp, cmd_type, tag); if (unlikely(err)) @@ -2797,6 +2810,7 @@ static int ufshcd_exec_dev_cmd(struct ufs_hba *hba, err = ufshcd_wait_for_dev_cmd(hba, lrbp, timeout); +out: ufshcd_add_query_upiu_trace(hba, tag, err ? "query_complete_err" : "query_complete"); @@ -4932,6 +4946,7 @@ static void __ufshcd_transfer_req_compl(struct ufs_hba *hba, for_each_set_bit(index, &completed_reqs, hba->nutrs) { lrbp = &hba->lrb[index]; + lrbp->in_use = false; lrbp->compl_time_stamp = ktime_get(); cmd = lrbp->cmd; if (cmd) { @@ -6374,8 +6389,12 @@ static int ufshcd_issue_devman_upiu_cmd(struct ufs_hba *hba, init_completion(&wait); lrbp = &hba->lrb[tag]; - WARN_ON(lrbp->cmd); + if (unlikely(lrbp->in_use)) { + err = -EBUSY; + goto out; + } + WARN_ON(lrbp->cmd); lrbp->cmd = NULL; lrbp->sense_bufflen = 0; lrbp->sense_buffer = NULL; @@ -6447,6 +6466,7 @@ static int ufshcd_issue_devman_upiu_cmd(struct ufs_hba *hba, } } +out: blk_put_request(req); out_unlock: up_read(&hba->clk_scaling_lock); @@ -6696,16 +6716,6 @@ static int ufshcd_abort(struct scsi_cmnd *cmd) BUG(); } - /* - * Task abort to the device W-LUN is illegal. When this command - * will fail, due to spec violation, scsi err handling next step - * will be to send LU reset which, again, is a spec violation. - * To avoid these unnecessary/illegal step we skip to the last error - * handling stage: reset and restore. - */ - if (lrbp->lun == UFS_UPIU_UFS_DEVICE_WLUN) - return ufshcd_eh_host_reset_handler(cmd); - ufshcd_hold(hba, false); reg = ufshcd_readl(hba, REG_UTP_TRANSFER_REQ_DOOR_BELL); /* If command is already aborted/completed, return SUCCESS */ @@ -6726,7 +6736,7 @@ static int ufshcd_abort(struct scsi_cmnd *cmd) * to reduce repeated printouts. For other aborted requests only print * basic details. */ - scsi_print_command(hba->lrb[tag].cmd); + scsi_print_command(cmd); if (!hba->req_abort_count) { ufshcd_update_reg_hist(&hba->ufs_stats.task_abort, 0); ufshcd_print_host_regs(hba); @@ -6745,6 +6755,30 @@ static int ufshcd_abort(struct scsi_cmnd *cmd) goto cleanup; } + /* + * Task abort to the device W-LUN is illegal. When this command + * will fail, due to spec violation, scsi err handling next step + * will be to send LU reset which, again, is a spec violation. + * To avoid these unnecessary/illegal steps, first we clean up + * the lrb taken by this cmd and mark the lrb as in_use, then + * queue the eh_work and bail. + */ + if (lrbp->lun == UFS_UPIU_UFS_DEVICE_WLUN) { + struct scsi_cmnd *cmd_in_lrb; + + spin_lock_irqsave(host->host_lock, flags); + cmd_in_lrb = lrbp->cmd; + if (cmd_in_lrb) { + __ufshcd_transfer_req_compl(hba, (1UL << tag)); + __set_bit(tag, &hba->outstanding_reqs); + lrbp->in_use = true; + hba->force_reset = true; + ufshcd_schedule_eh_work(hba); + } + spin_unlock_irqrestore(host->host_lock, flags); + goto out; + } + /* Skip task abort in case previous aborts failed and report failure */ if (lrbp->req_abort_skip) err = -EIO; diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index 1e680bf..66e5338 100644 --- a/drivers/scsi/ufs/ufshcd.h +++ b/drivers/scsi/ufs/ufshcd.h @@ -163,6 +163,7 @@ struct ufs_pm_lvl_states { * @crypto_key_slot: the key slot to use for inline crypto (-1 if none) * @data_unit_num: the data unit number for the first block for inline crypto * @req_abort_skip: skip request abort task flag + * @in_use: indicates that this lrb is still in use */ struct ufshcd_lrb { struct utp_transfer_req_desc *utr_descriptor_ptr; @@ -192,6 +193,7 @@ struct ufshcd_lrb { #endif bool req_abort_skip; + bool in_use; }; /**