From f4b3d35dfa4fb190d73d16934847365ad1b362ba Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Wed, 22 Sep 2021 12:10:59 +0300 Subject: [PATCH] FROMLIST: scsi: ufs: Fix task management completion The UFS driver uses blk_mq_tagset_busy_iter() when identifying task management requests to complete, however blk_mq_tagset_busy_iter() doesn't work. blk_mq_tagset_busy_iter() only iterates requests dispatched by the block layer. That appears as if it might have started since commit 37f4a24c2469a1 ("blk-mq: centralise related handling into blk_mq_get_driver_tag") which removed 'data->hctx->tags->rqs[rq->tag] = rq' from blk_mq_rq_ctx_init() which gets called: blk_get_request blk_mq_alloc_request __blk_mq_alloc_request blk_mq_rq_ctx_init Since UFS task management requests are not dispatched by the block layer, hctx->tags->rqs[rq->tag] remains NULL, and since blk_mq_tagset_busy_iter() relies on finding requests using hctx->tags->rqs[rq->tag], UFS task management requests are never found by blk_mq_tagset_busy_iter(). By using blk_mq_tagset_busy_iter(), the UFS driver was relying on internal details of the block layer, which was fragile and subsequently got broken. Fix by removing the use of blk_mq_tagset_busy_iter() and having the driver keep track of task management requests. Fixes: 1235fc569e0bf5 ("scsi: ufs: core: Fix task management request completion timeout") Fixes: 69a6c269c097d7 ("scsi: ufs: Use blk_{get,put}_request() to allocate and free TMFs") Cc: stable@vger.kernel.org Signed-off-by: Adrian Hunter Bug: 200291871 Link: https://lore.kernel.org/linux-scsi/20210922091059.4040-1-adrian.hunter@intel.com/ Change-Id: I4e11f40c7371fd66b3a6b570d06c956b113df142 Signed-off-by: Bart Van Assche --- drivers/scsi/ufs/ufshcd-add-info.h | 1 + drivers/scsi/ufs/ufshcd.c | 55 ++++++++++++++---------------- drivers/scsi/ufs/ufshcd.h | 6 ++++ 3 files changed, 32 insertions(+), 30 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd-add-info.h b/drivers/scsi/ufs/ufshcd-add-info.h index 8abe67ee8b7d..72ed34de6a61 100644 --- a/drivers/scsi/ufs/ufshcd-add-info.h +++ b/drivers/scsi/ufs/ufshcd-add-info.h @@ -11,6 +11,7 @@ */ struct ufs_hba_add_info { struct ufs_hba hba; + struct request **tmf_rqs; #ifdef CONFIG_SCSI_UFS_HPB struct ufshpb_dev_info hpb_dev; #endif diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 42f32b18e3d6..f160d0fcdc59 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -6364,27 +6364,6 @@ static irqreturn_t ufshcd_check_errors(struct ufs_hba *hba, u32 intr_status) return retval; } -struct ctm_info { - struct ufs_hba *hba; - unsigned long pending; - unsigned int ncpl; -}; - -static bool ufshcd_compl_tm(struct request *req, void *priv, bool reserved) -{ - struct ctm_info *const ci = priv; - struct completion *c; - - WARN_ON_ONCE(reserved); - if (test_bit(req->tag, &ci->pending)) - return true; - ci->ncpl++; - c = req->end_io_data; - if (c) - complete(c); - return true; -} - /** * ufshcd_tmc_handler - handle task management function completion * @hba: per adapter instance @@ -6395,18 +6374,25 @@ static bool ufshcd_compl_tm(struct request *req, void *priv, bool reserved) */ static irqreturn_t ufshcd_tmc_handler(struct ufs_hba *hba) { - unsigned long flags; - struct request_queue *q = hba->tmf_queue; - struct ctm_info ci = { - .hba = hba, - }; + struct request **tmf_rqs = ufs_hba_add_info(hba)->tmf_rqs; + unsigned long flags, pending, issued; + irqreturn_t ret = IRQ_NONE; + int tag; + + pending = ufshcd_readl(hba, REG_UTP_TASK_REQ_DOOR_BELL); spin_lock_irqsave(hba->host->host_lock, flags); - ci.pending = ufshcd_readl(hba, REG_UTP_TASK_REQ_DOOR_BELL); - blk_mq_tagset_busy_iter(q->tag_set, ufshcd_compl_tm, &ci); + issued = hba->outstanding_tasks & ~pending; + for_each_set_bit(tag, &issued, hba->nutmrs) { + struct request *req = tmf_rqs[tag]; + struct completion *c = req->end_io_data; + + complete(c); + ret = IRQ_HANDLED; + } spin_unlock_irqrestore(hba->host->host_lock, flags); - return ci.ncpl ? IRQ_HANDLED : IRQ_NONE; + return ret; } /** @@ -6511,6 +6497,7 @@ static int ufshcd_clear_tm_cmd(struct ufs_hba *hba, int tag) static int __ufshcd_issue_tm_cmd(struct ufs_hba *hba, struct utp_task_req_desc *treq, u8 tm_function) { + struct request **tmf_rqs = ufs_hba_add_info(hba)->tmf_rqs; struct request_queue *q = hba->tmf_queue; struct Scsi_Host *host = hba->host; DECLARE_COMPLETION_ONSTACK(wait); @@ -6529,9 +6516,9 @@ static int __ufshcd_issue_tm_cmd(struct ufs_hba *hba, ufshcd_hold(hba, false); spin_lock_irqsave(host->host_lock, flags); - blk_mq_start_request(req); task_tag = req->tag; + tmf_rqs[req->tag] = req; treq->req_header.dword_0 |= cpu_to_be32(task_tag); memcpy(hba->utmrdl_base_addr + task_tag, treq, sizeof(*treq)); @@ -6575,6 +6562,7 @@ static int __ufshcd_issue_tm_cmd(struct ufs_hba *hba, } spin_lock_irqsave(hba->host->host_lock, flags); + tmf_rqs[req->tag] = NULL; __clear_bit(task_tag, &hba->outstanding_tasks); spin_unlock_irqrestore(hba->host->host_lock, flags); @@ -9367,6 +9355,7 @@ static const struct blk_mq_ops ufshcd_tmf_ops = { */ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) { + struct request ***tmf_rqs = &ufs_hba_add_info(hba)->tmf_rqs; int err; struct Scsi_Host *host = hba->host; struct device *dev = hba->dev; @@ -9504,6 +9493,12 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) err = PTR_ERR(hba->tmf_queue); goto free_tmf_tag_set; } + *tmf_rqs = devm_kcalloc(hba->dev, hba->nutmrs, sizeof(**tmf_rqs), + GFP_KERNEL); + if (!*tmf_rqs) { + err = -ENOMEM; + goto free_tmf_queue; + } /* Reset the attached device */ ufshcd_vops_device_reset(hba); diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index 26274dad5e75..7150c886283e 100644 --- a/drivers/scsi/ufs/ufshcd.h +++ b/drivers/scsi/ufs/ufshcd.h @@ -843,6 +843,12 @@ struct ufs_hba { struct blk_mq_tag_set tmf_tag_set; struct request_queue *tmf_queue; +#if 0 + /* + * This has been moved into struct ufs_hba_add_info because of the GKI. + */ + struct request **tmf_rqs; +#endif struct uic_command *active_uic_cmd; struct mutex uic_cmd_mutex;