Commit a1ceea67 authored by Niklas Schnelle's avatar Niklas Schnelle Committed by Vasily Gorbik
Browse files

PCI/IOV: Introduce pci_iov_sysfs_link() function 



Currently pci_iov_add_virtfn() scans the SR-IOV BARs, adds the VF to the
bus and also creates the sysfs links between the newly added VF and its
parent PF.

With pdev->no_vf_scan fencing off the entire pci_iov_add_virtfn() call
s390 as the sole pdev->no_vf_scan user thus ends up missing these sysfs
links which are required for example by QEMU/libvirt.

Instead of duplicating the code refactor pci_iov_add_virtfn() to make
sysfs link creation callable separately.

Signed-off-by: default avatarNiklas Schnelle <schnelle@linux.ibm.com>
Acked-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarPierre Morel <pmorel@linux.ibm.com>
Link: https://lore.kernel.org/r/20200506154139.90609-1-schnelle@linux.ibm.com


Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
parent c70d82e9

drivers/pci/iov.c

+25 −11
Original line number Diff line number Diff line
@@ -133,12 +133,35 @@ static void pci_read_vf_config_common(struct pci_dev *virtfn) 
			     &physfn->sriov->subsystem_device);

}



int pci_iov_sysfs_link(struct pci_dev *dev,

		struct pci_dev *virtfn, int id)

{

	char buf[VIRTFN_ID_LEN];

	int rc;



	sprintf(buf, "virtfn%u", id);

	rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);

	if (rc)

		goto failed;

	rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");

	if (rc)

		goto failed1;



	kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);



	return 0;



failed1:

	sysfs_remove_link(&dev->dev.kobj, buf);

failed:

	return rc;

}



int pci_iov_add_virtfn(struct pci_dev *dev, int id)

{

	int i;

	int rc = -ENOMEM;

	u64 size;

	char buf[VIRTFN_ID_LEN];

	struct pci_dev *virtfn;

	struct resource *res;

	struct pci_sriov *iov = dev->sriov;
@@ -182,23 +205,14 @@ int pci_iov_add_virtfn(struct pci_dev *dev, int id) 
	}



	pci_device_add(virtfn, virtfn->bus);



	sprintf(buf, "virtfn%u", id);

	rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf);

	rc = pci_iov_sysfs_link(dev, virtfn, id);

	if (rc)

		goto failed1;

	rc = sysfs_create_link(&virtfn->dev.kobj, &dev->dev.kobj, "physfn");

	if (rc)

		goto failed2;



	kobject_uevent(&virtfn->dev.kobj, KOBJ_CHANGE);



	pci_bus_add_device(virtfn);



	return 0;



failed2:

	sysfs_remove_link(&dev->dev.kobj, buf);

failed1:

	pci_stop_and_remove_bus_device(virtfn);

	pci_dev_put(dev);

include/linux/pci.h

+8 −0
Original line number Diff line number Diff line
@@ -2048,6 +2048,8 @@ int pci_iov_virtfn_devfn(struct pci_dev *dev, int id); 


int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn);

void pci_disable_sriov(struct pci_dev *dev);



int pci_iov_sysfs_link(struct pci_dev *dev, struct pci_dev *virtfn, int id);

int pci_iov_add_virtfn(struct pci_dev *dev, int id);

void pci_iov_remove_virtfn(struct pci_dev *dev, int id);

int pci_num_vf(struct pci_dev *dev);
@@ -2073,6 +2075,12 @@ static inline int pci_iov_virtfn_devfn(struct pci_dev *dev, int id) 
}

static inline int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn)

{ return -ENODEV; }



static inline int pci_iov_sysfs_link(struct pci_dev *dev,

				     struct pci_dev *virtfn, int id)

{

	return -ENODEV;

}

static inline int pci_iov_add_virtfn(struct pci_dev *dev, int id)

{

	return -ENOSYS;

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