Commit 92bce97f authored by Niklas Schnelle's avatar Niklas Schnelle Committed by Joerg Roedel
Browse files

s390/pci: Fix reset of IOMMU software counters 



Together with enabling the Function Measurement Block
zpci_fmb_enable_device() also resets the software counters. This allows
to use "echo 0 > /sys/kernel/debug/pci/<dev>/statistics" followed by
echo "1 > /../statistics" to reset all counters. In commit c76c067e
("s390/pci: Use dma-iommu layer") this use of the now obsolete counters
in struct zpci_device was missed as was their removal. Fix this by
resetting the new counters and removing the old ones.

Fixes: c76c067e ("s390/pci: Use dma-iommu layer")
Signed-off-by: default avatarNiklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: default avatarMatthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20231004-dma_iommu_fix-v1-1-129777cd8232@linux.ibm.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 9f5b681e

arch/s390/include/asm/pci.h

+0 −4
Original line number Diff line number Diff line
@@ -173,10 +173,6 @@ struct zpci_dev { 
	struct zpci_fmb *fmb;

	u16		fmb_update;	/* update interval */

	u16		fmb_length;

	/* software counters */

	atomic64_t allocated_pages;

	atomic64_t mapped_pages;

	atomic64_t unmapped_pages;



	u8		version;

	enum pci_bus_speed max_bus_speed;

arch/s390/pci/pci.c

+10 −3
Original line number Diff line number Diff line
@@ -157,6 +157,7 @@ int zpci_unregister_ioat(struct zpci_dev *zdev, u8 dmaas) 
int zpci_fmb_enable_device(struct zpci_dev *zdev)

{

	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_SET_MEASURE);

	struct zpci_iommu_ctrs *ctrs;

	struct zpci_fib fib = {0};

	u8 cc, status;
@@ -169,9 +170,15 @@ int zpci_fmb_enable_device(struct zpci_dev *zdev) 
	WARN_ON((u64) zdev->fmb & 0xf);



	/* reset software counters */

	atomic64_set(&zdev->allocated_pages, 0);

	atomic64_set(&zdev->mapped_pages, 0);

	atomic64_set(&zdev->unmapped_pages, 0);

	ctrs = zpci_get_iommu_ctrs(zdev);

	if (ctrs) {

		atomic64_set(&ctrs->mapped_pages, 0);

		atomic64_set(&ctrs->unmapped_pages, 0);

		atomic64_set(&ctrs->global_rpcits, 0);

		atomic64_set(&ctrs->sync_map_rpcits, 0);

		atomic64_set(&ctrs->sync_rpcits, 0);

	}





	fib.fmb_addr = virt_to_phys(zdev->fmb);

	fib.gd = zdev->gisa;