diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-pci | 22 | ||||
| -rw-r--r-- | Documentation/PCI/pci-iov-howto.txt | 12 | ||||
| -rw-r--r-- | drivers/pci/iov.c | 1 | ||||
| -rw-r--r-- | drivers/pci/pci-driver.c | 22 | ||||
| -rw-r--r-- | drivers/pci/pci-sysfs.c | 28 | ||||
| -rw-r--r-- | drivers/pci/pci.h | 1 |
6 files changed, 82 insertions, 4 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index 5a1732b78707..b728f700340d 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -301,3 +301,25 @@ Contact: Emil Velikov <emil.l.velikov@gmail.com> Description: This file contains the revision field of the the PCI device. The value comes from device config space. The file is read only. + +What: /sys/bus/pci/devices/.../sriov_drivers_autoprobe +Date: April 2017 +Contact: Bodong Wang<bodong@mellanox.com> +Description: + This file is associated with the PF of a device that + supports SR-IOV. It determines whether newly-enabled VFs + are immediately bound to a driver. It initially contains + 1, which means the kernel automatically binds VFs to a + compatible driver immediately after they are enabled. If + an application writes 0 to the file before enabling VFs, + the kernel will not bind VFs to a driver. + + A typical use case is to write 0 to this file, then enable + VFs, then assign the newly-created VFs to virtual machines. + Note that changing this file does not affect already- + enabled VFs. In this scenario, the user must first disable + the VFs, write 0 to sriov_drivers_autoprobe, then re-enable + the VFs. + + This is similar to /sys/bus/pci/drivers_autoprobe, but + affects only the VFs associated with a specific PF. diff --git a/Documentation/PCI/pci-iov-howto.txt b/Documentation/PCI/pci-iov-howto.txt index 2d91ae251982..d2a84151e99c 100644 --- a/Documentation/PCI/pci-iov-howto.txt +++ b/Documentation/PCI/pci-iov-howto.txt @@ -68,6 +68,18 @@ To disable SR-IOV capability: echo 0 > \ /sys/bus/pci/devices/<DOMAIN:BUS:DEVICE.FUNCTION>/sriov_numvfs +To enable auto probing VFs by a compatible driver on the host, run +command below before enabling SR-IOV capabilities. This is the +default behavior. + echo 1 > \ + /sys/bus/pci/devices/<DOMAIN:BUS:DEVICE.FUNCTION>/sriov_drivers_autoprobe + +To disable auto probing VFs by a compatible driver on the host, run +command below before enabling SR-IOV capabilities. Updating this +entry will not affect VFs which are already probed. + echo 0 > \ + /sys/bus/pci/devices/<DOMAIN:BUS:DEVICE.FUNCTION>/sriov_drivers_autoprobe + 3.2 Usage example Following piece of code illustrates the usage of the SR-IOV API. diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c index 2479ae876482..d9dc7363ac77 100644 --- a/drivers/pci/iov.c +++ b/drivers/pci/iov.c @@ -450,6 +450,7 @@ found: iov->total_VFs = total; iov->pgsz = pgsz; iov->self = dev; + iov->drivers_autoprobe = true; pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap); pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link); if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END) diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index afa72717a979..f99f7fe749b8 100644 --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -394,6 +394,18 @@ void __weak pcibios_free_irq(struct pci_dev *dev) { } +#ifdef CONFIG_PCI_IOV +static inline bool pci_device_can_probe(struct pci_dev *pdev) +{ + return (!pdev->is_virtfn || pdev->physfn->sriov->drivers_autoprobe); +} +#else +static inline bool pci_device_can_probe(struct pci_dev *pdev) +{ + return true; +} +#endif + static int pci_device_probe(struct device *dev) { int error; @@ -405,10 +417,12 @@ static int pci_device_probe(struct device *dev) return error; pci_dev_get(pci_dev); - error = __pci_device_probe(drv, pci_dev); - if (error) { - pcibios_free_irq(pci_dev); - pci_dev_put(pci_dev); + if (pci_device_can_probe(pci_dev)) { + error = __pci_device_probe(drv, pci_dev); + if (error) { + pcibios_free_irq(pci_dev); + pci_dev_put(pci_dev); + } } return error; diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index 25d010d449a3..369c999683ca 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -526,10 +526,37 @@ exit: return count; } +static ssize_t sriov_drivers_autoprobe_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct pci_dev *pdev = to_pci_dev(dev); + + return sprintf(buf, "%u\n", pdev->sriov->drivers_autoprobe); +} + +static ssize_t sriov_drivers_autoprobe_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct pci_dev *pdev = to_pci_dev(dev); + bool drivers_autoprobe; + + if (kstrtobool(buf, &drivers_autoprobe) < 0) + return -EINVAL; + + pdev->sriov->drivers_autoprobe = drivers_autoprobe; + + return count; +} + static struct device_attribute sriov_totalvfs_attr = __ATTR_RO(sriov_totalvfs); static struct device_attribute sriov_numvfs_attr = __ATTR(sriov_numvfs, (S_IRUGO|S_IWUSR|S_IWGRP), sriov_numvfs_show, sriov_numvfs_store); +static struct device_attribute sriov_drivers_autoprobe_attr = + __ATTR(sriov_drivers_autoprobe, (S_IRUGO|S_IWUSR|S_IWGRP), + sriov_drivers_autoprobe_show, sriov_drivers_autoprobe_store); #endif /* CONFIG_PCI_IOV */ static ssize_t driver_override_store(struct device *dev, @@ -1549,6 +1576,7 @@ static struct attribute_group pci_dev_hp_attr_group = { static struct attribute *sriov_dev_attrs[] = { &sriov_totalvfs_attr.attr, &sriov_numvfs_attr.attr, + &sriov_drivers_autoprobe_attr.attr, NULL, }; diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 8dd38e69d6f2..3ba7d586f522 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -272,6 +272,7 @@ struct pci_sriov { struct pci_dev *self; /* this PF */ struct mutex lock; /* lock for setting sriov_numvfs in sysfs */ resource_size_t barsz[PCI_SRIOV_NUM_BARS]; /* VF BAR size */ + bool drivers_autoprobe; /* auto probing of VFs by driver */ }; #ifdef CONFIG_PCI_ATS |