Commit f019d781 authored by Vinicius Costa Gomes's avatar Vinicius Costa Gomes Committed by Vinod Koul
Browse files

dmaengine: idxd: Flush kernel workqueues on Function Level Reset 



When a Function Level Reset (FLR) happens, terminate the pending
descriptors that were issued by in-kernel users and disable the
interrupts associated with those. They will be re-enabled after FLR
finishes.

idxd_wq_flush_desc() is declared on idxd.h because it's going to be
used in by the DMA backend in a future patch.

Signed-off-by: default avatarVinicius Costa Gomes <vinicius.gomes@intel.com>
Reviewed-by: default avatarDave Jiang <dave.jiang@intel.com>
Link: https://patch.msgid.link/20260121-idxd-fix-flr-on-kernel-queues-v3-v3-4-7ed70658a9d1@intel.com


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent d6077df7

drivers/dma/idxd/device.c

+22 −0
Original line number Diff line number Diff line
@@ -1339,6 +1339,11 @@ void idxd_wq_free_irq(struct idxd_wq *wq) 


	free_irq(ie->vector, ie);

	idxd_flush_pending_descs(ie);



	/* The interrupt might have been already released by FLR */

	if (ie->int_handle == INVALID_INT_HANDLE)

		return;



	if (idxd->request_int_handles)

		idxd_device_release_int_handle(idxd, ie->int_handle, IDXD_IRQ_MSIX);

	idxd_device_clear_perm_entry(idxd, ie);
@@ -1347,6 +1352,23 @@ void idxd_wq_free_irq(struct idxd_wq *wq) 
	ie->pasid = IOMMU_PASID_INVALID;

}



void idxd_wq_flush_descs(struct idxd_wq *wq)

{

	struct idxd_irq_entry *ie = &wq->ie;

	struct idxd_device *idxd = wq->idxd;



	guard(mutex)(&wq->wq_lock);



	if (wq->state != IDXD_WQ_ENABLED || wq->type != IDXD_WQT_KERNEL)

		return;



	idxd_flush_pending_descs(ie);

	if (idxd->request_int_handles)

		idxd_device_release_int_handle(idxd, ie->int_handle, IDXD_IRQ_MSIX);

	idxd_device_clear_perm_entry(idxd, ie);

	ie->int_handle = INVALID_INT_HANDLE;

}



int idxd_wq_request_irq(struct idxd_wq *wq)

{

	struct idxd_device *idxd = wq->idxd;

drivers/dma/idxd/idxd.h

+1 −0
Original line number Diff line number Diff line
@@ -803,6 +803,7 @@ void idxd_wq_quiesce(struct idxd_wq *wq); 
int idxd_wq_init_percpu_ref(struct idxd_wq *wq);

void idxd_wq_free_irq(struct idxd_wq *wq);

int idxd_wq_request_irq(struct idxd_wq *wq);

void idxd_wq_flush_descs(struct idxd_wq *wq);



/* submission */

int idxd_submit_desc(struct idxd_wq *wq, struct idxd_desc *desc);

drivers/dma/idxd/irq.c

+16 −0
Original line number Diff line number Diff line
@@ -397,6 +397,17 @@ static void idxd_device_flr(struct work_struct *work) 
		dev_err(&idxd->pdev->dev, "FLR failed\n");

}



static void idxd_wqs_flush_descs(struct idxd_device *idxd)

{

	int i;



	for (i = 0; i < idxd->max_wqs; i++) {

		struct idxd_wq *wq = idxd->wqs[i];



		idxd_wq_flush_descs(wq);

	}

}



static irqreturn_t idxd_halt(struct idxd_device *idxd)

{

	union gensts_reg gensts;
@@ -415,6 +426,11 @@ static irqreturn_t idxd_halt(struct idxd_device *idxd) 
		} else if (gensts.reset_type == IDXD_DEVICE_RESET_FLR) {

			idxd->state = IDXD_DEV_HALTED;

			idxd_mask_error_interrupts(idxd);

			/* Flush all pending descriptors, and disable

			 * interrupts, they will be re-enabled when FLR

			 * concludes.

			 */

			idxd_wqs_flush_descs(idxd);

			dev_dbg(&idxd->pdev->dev,

				"idxd halted, doing FLR. After FLR, configs are restored\n");

			INIT_WORK(&idxd->work, idxd_device_flr);