Commit 5a8eb242 authored by Alexander Duyck's avatar Alexander Duyck Committed by Jeff Kirsher

pci: Add SRIOV helper function to determine if VFs are assigned to guest

This function is meant to add a helper function that will determine if a PF
has any VFs that are currently assigned to a guest.  We currently have been
implementing this function per driver, and going forward I would like to avoid
that by making this function generic and using this helper.

v2: Removed extern from declaration of pci_vfs_assigned in pci.h and return
    0 if SR-IOV is disabled with is inline with other PCI SRIOV functions.
Signed-off-by: default avatarAlexander Duyck <alexander.h.duyck@intel.com>
Acked-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Signed-off-by: default avatarJeff Kirsher <jeffrey.t.kirsher@intel.com>
parent d44e7a9a
......@@ -728,6 +728,47 @@ int pci_num_vf(struct pci_dev *dev)
}
EXPORT_SYMBOL_GPL(pci_num_vf);
/**
* pci_vfs_assigned - returns number of VFs are assigned to a guest
* @dev: the PCI device
*
* Returns number of VFs belonging to this device that are assigned to a guest.
* If device is not a physical function returns -ENODEV.
*/
int pci_vfs_assigned(struct pci_dev *dev)
{
struct pci_dev *vfdev;
unsigned int vfs_assigned = 0;
unsigned short dev_id;
/* only search if we are a PF */
if (!dev->is_physfn)
return 0;
/*
* determine the device ID for the VFs, the vendor ID will be the
* same as the PF so there is no need to check for that one
*/
pci_read_config_word(dev, dev->sriov->pos + PCI_SRIOV_VF_DID, &dev_id);
/* loop through all the VFs to see if we own any that are assigned */
vfdev = pci_get_device(dev->vendor, dev_id, NULL);
while (vfdev) {
/*
* It is considered assigned if it is a virtual function with
* our dev as the physical function and the assigned bit is set
*/
if (vfdev->is_virtfn && (vfdev->physfn == dev) &&
(vfdev->dev_flags & PCI_DEV_FLAGS_ASSIGNED))
vfs_assigned++;
vfdev = pci_get_device(dev->vendor, dev_id, vfdev);
}
return vfs_assigned;
}
EXPORT_SYMBOL_GPL(pci_vfs_assigned);
/**
* pci_sriov_set_totalvfs -- reduce the TotalVFs available
* @dev: the PCI PF device
......
......@@ -1644,6 +1644,7 @@ extern int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn);
extern void pci_disable_sriov(struct pci_dev *dev);
extern irqreturn_t pci_sriov_migration(struct pci_dev *dev);
extern int pci_num_vf(struct pci_dev *dev);
int pci_vfs_assigned(struct pci_dev *dev);
extern int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs);
extern int pci_sriov_get_totalvfs(struct pci_dev *dev);
#else
......@@ -1662,6 +1663,10 @@ static inline int pci_num_vf(struct pci_dev *dev)
{
return 0;
}
static inline int pci_vfs_assigned(struct pci_dev *dev)
{
return 0;
}
static inline int pci_sriov_set_totalvfs(struct pci_dev *dev, u16 numvfs)
{
return 0;
......
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