From e115c6a95d506d1cb594bdcec3c7da3d3b84293a Mon Sep 17 00:00:00 2001 From: Dave Jiang Date: Tue, 26 Oct 2021 14:36:23 -0700 Subject: [PATCH] dmaengine: idxd: add helper for per interrupt handle drain mainline inclusion from mainline-v5.17 commit 46c6df1c958e55558212cfa94cad201eae48d684 category: feature bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I596WO CVE: NA Intel-SIG: commit 46c6df1c958e dmaengine: idxd: add helper for per interrupt handle drain. Incremental backporting patches for DSA/IAA on Intel Xeon platform. -------------------------------- The helper is called at the completion of the interrupt handle refresh event. It issues drain descriptors to each of the wq with associated interrupt handle. The drain descriptor will have interrupt request set but without completion record. This will ensure all descriptors with incorrect interrupt completion handle get drained and a completion interrupt is triggered for the guest driver to process them. Reviewed-by: Kevin Tian Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/163528418315.3925689.7944718440052849626.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Vinod Koul Signed-off-by: Xiaochen Shen --- drivers/dma/idxd/irq.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/drivers/dma/idxd/irq.c b/drivers/dma/idxd/irq.c index 47b6fc894a23..f980486db590 100644 --- a/drivers/dma/idxd/irq.c +++ b/drivers/dma/idxd/irq.c @@ -55,6 +55,45 @@ static void idxd_device_reinit(struct work_struct *work) idxd_device_clear_state(idxd); } +/* + * The function sends a drain descriptor for the interrupt handle. The drain ensures + * all descriptors with this interrupt handle is flushed and the interrupt + * will allow the cleanup of the outstanding descriptors. + */ +static void idxd_int_handle_revoke_drain(struct idxd_irq_entry *ie) +{ + struct idxd_wq *wq = ie->wq; + struct idxd_device *idxd = ie->idxd; + struct device *dev = &idxd->pdev->dev; + struct dsa_hw_desc desc = {}; + void __iomem *portal; + int rc; + + /* Issue a simple drain operation with interrupt but no completion record */ + desc.flags = IDXD_OP_FLAG_RCI; + desc.opcode = DSA_OPCODE_DRAIN; + desc.priv = 1; + + if (ie->pasid != INVALID_IOASID) + desc.pasid = ie->pasid; + desc.int_handle = ie->int_handle; + portal = idxd_wq_portal_addr(wq); + + /* + * The wmb() makes sure that the descriptor is all there before we + * issue. + */ + wmb(); + if (wq_dedicated(wq)) { + iosubmit_cmds512(portal, &desc, 1); + } else { + rc = enqcmds(portal, &desc); + /* This should not fail unless hardware failed. */ + if (rc < 0) + dev_warn(dev, "Failed to submit drain desc on wq %d\n", wq->id); + } +} + static int process_misc_interrupts(struct idxd_device *idxd, u32 cause) { struct device *dev = &idxd->pdev->dev; -- GitLab