diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-pci | 29 | ||||
| -rw-r--r-- | drivers/pci/iov.c | 102 | ||||
| -rw-r--r-- | drivers/pci/pci-sysfs.c | 3 | ||||
| -rw-r--r-- | drivers/pci/pci.h | 3 | ||||
| -rw-r--r-- | include/linux/pci.h | 8 |
5 files changed, 137 insertions, 8 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index 25c9c39770c6..e5cfd170b491 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -375,3 +375,32 @@ Description: The value comes from the PCI kernel device state and can be one of: "unknown", "error", "D0", D1", "D2", "D3hot", "D3cold". The file is read only. + +What: /sys/bus/pci/devices/.../sriov_vf_total_msix +Date: January 2021 +Contact: Leon Romanovsky <leonro@nvidia.com> +Description: + This file is associated with a SR-IOV physical function (PF). + It contains the total number of MSI-X vectors available for + assignment to all virtual functions (VFs) associated with PF. + The value will be zero if the device doesn't support this + functionality. For supported devices, the value will be + constant and won't be changed after MSI-X vectors assignment. + +What: /sys/bus/pci/devices/.../sriov_vf_msix_count +Date: January 2021 +Contact: Leon Romanovsky <leonro@nvidia.com> +Description: + This file is associated with a SR-IOV virtual function (VF). + It allows configuration of the number of MSI-X vectors for + the VF. This allows devices that have a global pool of MSI-X + vectors to optimally divide them between VFs based on VF usage. + + The values accepted are: + * > 0 - this number will be reported as the Table Size in the + VF's MSI-X capability + * < 0 - not valid + * = 0 - will reset to the device default value + + The file is writable if the PF is bound to a driver that + implements ->sriov_set_msix_vec_count(). diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c index 4afd4ee4f7f0..afc06e6ce115 100644 --- a/drivers/pci/iov.c +++ b/drivers/pci/iov.c @@ -31,6 +31,7 @@ int pci_iov_virtfn_devfn(struct pci_dev *dev, int vf_id) return (dev->devfn + dev->sriov->offset + dev->sriov->stride * vf_id) & 0xff; } +EXPORT_SYMBOL_GPL(pci_iov_virtfn_devfn); /* * Per SR-IOV spec sec 3.3.10 and 3.3.11, First VF Offset and VF Stride may @@ -157,6 +158,92 @@ failed: return rc; } +#ifdef CONFIG_PCI_MSI +static ssize_t sriov_vf_total_msix_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct pci_dev *pdev = to_pci_dev(dev); + u32 vf_total_msix = 0; + + device_lock(dev); + if (!pdev->driver || !pdev->driver->sriov_get_vf_total_msix) + goto unlock; + + vf_total_msix = pdev->driver->sriov_get_vf_total_msix(pdev); +unlock: + device_unlock(dev); + return sysfs_emit(buf, "%u\n", vf_total_msix); +} +static DEVICE_ATTR_RO(sriov_vf_total_msix); + +static ssize_t sriov_vf_msix_count_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct pci_dev *vf_dev = to_pci_dev(dev); + struct pci_dev *pdev = pci_physfn(vf_dev); + int val, ret; + + ret = kstrtoint(buf, 0, &val); + if (ret) + return ret; + + if (val < 0) + return -EINVAL; + + device_lock(&pdev->dev); + if (!pdev->driver || !pdev->driver->sriov_set_msix_vec_count) { + ret = -EOPNOTSUPP; + goto err_pdev; + } + + device_lock(&vf_dev->dev); + if (vf_dev->driver) { + /* + * A driver is already attached to this VF and has configured + * itself based on the current MSI-X vector count. Changing + * the vector size could mess up the driver, so block it. + */ + ret = -EBUSY; + goto err_dev; + } + + ret = pdev->driver->sriov_set_msix_vec_count(vf_dev, val); + +err_dev: + device_unlock(&vf_dev->dev); +err_pdev: + device_unlock(&pdev->dev); + return ret ? : count; +} +static DEVICE_ATTR_WO(sriov_vf_msix_count); +#endif + +static struct attribute *sriov_vf_dev_attrs[] = { +#ifdef CONFIG_PCI_MSI + &dev_attr_sriov_vf_msix_count.attr, +#endif + NULL, +}; + +static umode_t sriov_vf_attrs_are_visible(struct kobject *kobj, + struct attribute *a, int n) +{ + struct device *dev = kobj_to_dev(kobj); + struct pci_dev *pdev = to_pci_dev(dev); + + if (!pdev->is_virtfn) + return 0; + + return a->mode; +} + +const struct attribute_group sriov_vf_dev_attr_group = { + .attrs = sriov_vf_dev_attrs, + .is_visible = sriov_vf_attrs_are_visible, +}; + int pci_iov_add_virtfn(struct pci_dev *dev, int id) { int i; @@ -400,18 +487,21 @@ static DEVICE_ATTR_RO(sriov_stride); static DEVICE_ATTR_RO(sriov_vf_device); static DEVICE_ATTR_RW(sriov_drivers_autoprobe); -static struct attribute *sriov_dev_attrs[] = { +static struct attribute *sriov_pf_dev_attrs[] = { &dev_attr_sriov_totalvfs.attr, &dev_attr_sriov_numvfs.attr, &dev_attr_sriov_offset.attr, &dev_attr_sriov_stride.attr, &dev_attr_sriov_vf_device.attr, &dev_attr_sriov_drivers_autoprobe.attr, +#ifdef CONFIG_PCI_MSI + &dev_attr_sriov_vf_total_msix.attr, +#endif NULL, }; -static umode_t sriov_attrs_are_visible(struct kobject *kobj, - struct attribute *a, int n) +static umode_t sriov_pf_attrs_are_visible(struct kobject *kobj, + struct attribute *a, int n) { struct device *dev = kobj_to_dev(kobj); @@ -421,9 +511,9 @@ static umode_t sriov_attrs_are_visible(struct kobject *kobj, return a->mode; } -const struct attribute_group sriov_dev_attr_group = { - .attrs = sriov_dev_attrs, - .is_visible = sriov_attrs_are_visible, +const struct attribute_group sriov_pf_dev_attr_group = { + .attrs = sriov_pf_dev_attrs, + .is_visible = sriov_pf_attrs_are_visible, }; int __weak pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs) diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c index f8afd54ca3e1..a6b8fbbba6d2 100644 --- a/drivers/pci/pci-sysfs.c +++ b/drivers/pci/pci-sysfs.c @@ -1567,7 +1567,8 @@ static const struct attribute_group *pci_dev_attr_groups[] = { &pci_dev_attr_group, &pci_dev_hp_attr_group, #ifdef CONFIG_PCI_IOV - &sriov_dev_attr_group, + &sriov_pf_dev_attr_group, + &sriov_vf_dev_attr_group, #endif &pci_bridge_attr_group, &pcie_dev_attr_group, diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index ef7c4661314f..afb87b917f07 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -501,7 +501,8 @@ void pci_iov_update_resource(struct pci_dev *dev, int resno); resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno); void pci_restore_iov_state(struct pci_dev *dev); int pci_iov_bus_range(struct pci_bus *bus); -extern const struct attribute_group sriov_dev_attr_group; +extern const struct attribute_group sriov_pf_dev_attr_group; +extern const struct attribute_group sriov_vf_dev_attr_group; #else static inline int pci_iov_init(struct pci_dev *dev) { diff --git a/include/linux/pci.h b/include/linux/pci.h index 86c799c97b77..9b575a676888 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -856,6 +856,12 @@ struct module; * e.g. drivers/net/e100.c. * @sriov_configure: Optional driver callback to allow configuration of * number of VFs to enable via sysfs "sriov_numvfs" file. + * @sriov_set_msix_vec_count: PF Driver callback to change number of MSI-X + * vectors on a VF. Triggered via sysfs "sriov_vf_msix_count". + * This will change MSI-X Table Size in the VF Message Control + * registers. + * @sriov_get_vf_total_msix: PF driver callback to get the total number of + * MSI-X vectors available for distribution to the VFs. * @err_handler: See Documentation/PCI/pci-error-recovery.rst * @groups: Sysfs attribute groups. * @driver: Driver model structure. @@ -871,6 +877,8 @@ struct pci_driver { int (*resume)(struct pci_dev *dev); /* Device woken up */ void (*shutdown)(struct pci_dev *dev); int (*sriov_configure)(struct pci_dev *dev, int num_vfs); /* On PF */ + int (*sriov_set_msix_vec_count)(struct pci_dev *vf, int msix_vec_count); /* On PF */ + u32 (*sriov_get_vf_total_msix)(struct pci_dev *pf); const struct pci_error_handlers *err_handler; const struct attribute_group **groups; struct device_driver driver; |