From dd7cc44d0bcec5e9c42fe52e88dc254ae62eac8d Mon Sep 17 00:00:00 2001 From: Yu Zhao Date: Fri, 20 Mar 2009 11:25:15 +0800 Subject: [PATCH] PCI: add SR-IOV API for Physical Function driver Add or remove the Virtual Function when the SR-IOV is enabled or disabled by the device driver. This can happen anytime rather than only at the device probe stage. Reviewed-by: Matthew Wilcox Signed-off-by: Yu Zhao Signed-off-by: Jesse Barnes --- drivers/pci/iov.c | 314 ++++++++++++++++++++++++++++++++++++++++++++ drivers/pci/pci.h | 2 + include/linux/pci.h | 19 ++- 3 files changed, 334 insertions(+), 1 deletion(-) diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c index 5ddfc09a8d3f..d0ff8ad8f7ba 100644 --- a/drivers/pci/iov.c +++ b/drivers/pci/iov.c @@ -13,6 +13,7 @@ #include #include "pci.h" +#define VIRTFN_ID_LEN 16 static inline u8 virtfn_bus(struct pci_dev *dev, int id) { @@ -26,6 +27,284 @@ static inline u8 virtfn_devfn(struct pci_dev *dev, int id) dev->sriov->stride * id) & 0xff; } +static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr) +{ + int rc; + struct pci_bus *child; + + if (bus->number == busnr) + return bus; + + child = pci_find_bus(pci_domain_nr(bus), busnr); + if (child) + return child; + + child = pci_add_new_bus(bus, NULL, busnr); + if (!child) + return NULL; + + child->subordinate = busnr; + child->dev.parent = bus->bridge; + rc = pci_bus_add_child(child); + if (rc) { + pci_remove_bus(child); + return NULL; + } + + return child; +} + +static void virtfn_remove_bus(struct pci_bus *bus, int busnr) +{ + struct pci_bus *child; + + if (bus->number == busnr) + return; + + child = pci_find_bus(pci_domain_nr(bus), busnr); + BUG_ON(!child); + + if (list_empty(&child->devices)) + pci_remove_bus(child); +} + +static int virtfn_add(struct pci_dev *dev, int id, int reset) +{ + int i; + int rc; + u64 size; + char buf[VIRTFN_ID_LEN]; + struct pci_dev *virtfn; + struct resource *res; + struct pci_sriov *iov = dev->sriov; + + virtfn = alloc_pci_dev(); + if (!virtfn) + return -ENOMEM; + + mutex_lock(&iov->dev->sriov->lock); + virtfn->bus = virtfn_add_bus(dev->bus, virtfn_bus(dev, id)); + if (!virtfn->bus) { + kfree(virtfn); + mutex_unlock(&iov->dev->sriov->lock); + return -ENOMEM; + } + virtfn->devfn = virtfn_devfn(dev, id); + virtfn->vendor = dev->vendor; + pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_DID, &virtfn->device); + pci_setup_device(virtfn); + virtfn->dev.parent = dev->dev.parent; + + for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { + res = dev->resource + PCI_IOV_RESOURCES + i; + if (!res->parent) + continue; + virtfn->resource[i].name = pci_name(virtfn); + virtfn->resource[i].flags = res->flags; + size = resource_size(res); + do_div(size, iov->total); + virtfn->resource[i].start = res->start + size * id; + virtfn->resource[i].end = virtfn->resource[i].start + size - 1; + rc = request_resource(res, &virtfn->resource[i]); + BUG_ON(rc); + } + + if (reset) + pci_execute_reset_function(virtfn); + + pci_device_add(virtfn, virtfn->bus); + mutex_unlock(&iov->dev->sriov->lock); + + virtfn->physfn = pci_dev_get(dev); + virtfn->is_virtfn = 1; + + rc = pci_bus_add_device(virtfn); + if (rc) + goto failed1; + sprintf(buf, "virtfn%u", id); + rc = sysfs_create_link(&dev->dev.kobj, &virtfn->dev.kobj, buf); + 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); + + return 0; + +failed2: + sysfs_remove_link(&dev->dev.kobj, buf); +failed1: + pci_dev_put(dev); + mutex_lock(&iov->dev->sriov->lock); + pci_remove_bus_device(virtfn); + virtfn_remove_bus(dev->bus, virtfn_bus(dev, id)); + mutex_unlock(&iov->dev->sriov->lock); + + return rc; +} + +static void virtfn_remove(struct pci_dev *dev, int id, int reset) +{ + char buf[VIRTFN_ID_LEN]; + struct pci_bus *bus; + struct pci_dev *virtfn; + struct pci_sriov *iov = dev->sriov; + + bus = pci_find_bus(pci_domain_nr(dev->bus), virtfn_bus(dev, id)); + if (!bus) + return; + + virtfn = pci_get_slot(bus, virtfn_devfn(dev, id)); + if (!virtfn) + return; + + pci_dev_put(virtfn); + + if (reset) { + device_release_driver(&virtfn->dev); + pci_execute_reset_function(virtfn); + } + + sprintf(buf, "virtfn%u", id); + sysfs_remove_link(&dev->dev.kobj, buf); + sysfs_remove_link(&virtfn->dev.kobj, "physfn"); + + mutex_lock(&iov->dev->sriov->lock); + pci_remove_bus_device(virtfn); + virtfn_remove_bus(dev->bus, virtfn_bus(dev, id)); + mutex_unlock(&iov->dev->sriov->lock); + + pci_dev_put(dev); +} + +static int sriov_enable(struct pci_dev *dev, int nr_virtfn) +{ + int rc; + int i, j; + int nres; + u16 offset, stride, initial; + struct resource *res; + struct pci_dev *pdev; + struct pci_sriov *iov = dev->sriov; + + if (!nr_virtfn) + return 0; + + if (iov->nr_virtfn) + return -EINVAL; + + pci_read_config_word(dev, iov->pos + PCI_SRIOV_INITIAL_VF, &initial); + if (initial > iov->total || + (!(iov->cap & PCI_SRIOV_CAP_VFM) && (initial != iov->total))) + return -EIO; + + if (nr_virtfn < 0 || nr_virtfn > iov->total || + (!(iov->cap & PCI_SRIOV_CAP_VFM) && (nr_virtfn > initial))) + return -EINVAL; + + pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn); + pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &offset); + pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &stride); + if (!offset || (nr_virtfn > 1 && !stride)) + return -EIO; + + nres = 0; + for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { + res = dev->resource + PCI_IOV_RESOURCES + i; + if (res->parent) + nres++; + } + if (nres != iov->nres) { + dev_err(&dev->dev, "not enough MMIO resources for SR-IOV\n"); + return -ENOMEM; + } + + iov->offset = offset; + iov->stride = stride; + + if (virtfn_bus(dev, nr_virtfn - 1) > dev->bus->subordinate) { + dev_err(&dev->dev, "SR-IOV: bus number out of range\n"); + return -ENOMEM; + } + + if (iov->link != dev->devfn) { + pdev = pci_get_slot(dev->bus, iov->link); + if (!pdev) + return -ENODEV; + + pci_dev_put(pdev); + + if (!pdev->is_physfn) + return -ENODEV; + + rc = sysfs_create_link(&dev->dev.kobj, + &pdev->dev.kobj, "dep_link"); + if (rc) + return rc; + } + + iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE; + pci_block_user_cfg_access(dev); + pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); + msleep(100); + pci_unblock_user_cfg_access(dev); + + iov->initial = initial; + if (nr_virtfn < initial) + initial = nr_virtfn; + + for (i = 0; i < initial; i++) { + rc = virtfn_add(dev, i, 0); + if (rc) + goto failed; + } + + kobject_uevent(&dev->dev.kobj, KOBJ_CHANGE); + iov->nr_virtfn = nr_virtfn; + + return 0; + +failed: + for (j = 0; j < i; j++) + virtfn_remove(dev, j, 0); + + iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE); + pci_block_user_cfg_access(dev); + pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); + ssleep(1); + pci_unblock_user_cfg_access(dev); + + if (iov->link != dev->devfn) + sysfs_remove_link(&dev->dev.kobj, "dep_link"); + + return rc; +} + +static void sriov_disable(struct pci_dev *dev) +{ + int i; + struct pci_sriov *iov = dev->sriov; + + if (!iov->nr_virtfn) + return; + + for (i = 0; i < iov->nr_virtfn; i++) + virtfn_remove(dev, i, 0); + + iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE); + pci_block_user_cfg_access(dev); + pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); + ssleep(1); + pci_unblock_user_cfg_access(dev); + + if (iov->link != dev->devfn) + sysfs_remove_link(&dev->dev.kobj, "dep_link"); + + iov->nr_virtfn = 0; +} + static int sriov_init(struct pci_dev *dev, int pos) { int i; @@ -132,6 +411,8 @@ failed: static void sriov_release(struct pci_dev *dev) { + BUG_ON(dev->sriov->nr_virtfn); + if (dev == dev->sriov->dev) mutex_destroy(&dev->sriov->lock); else @@ -155,6 +436,7 @@ static void sriov_restore_state(struct pci_dev *dev) pci_update_resource(dev, i); pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz); + pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, iov->nr_virtfn); pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); if (iov->ctrl & PCI_SRIOV_CTRL_VFE) msleep(100); @@ -245,3 +527,35 @@ int pci_iov_bus_range(struct pci_bus *bus) return max ? max - bus->number : 0; } + +/** + * pci_enable_sriov - enable the SR-IOV capability + * @dev: the PCI device + * + * Returns 0 on success, or negative on failure. + */ +int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn) +{ + might_sleep(); + + if (!dev->is_physfn) + return -ENODEV; + + return sriov_enable(dev, nr_virtfn); +} +EXPORT_SYMBOL_GPL(pci_enable_sriov); + +/** + * pci_disable_sriov - disable the SR-IOV capability + * @dev: the PCI device + */ +void pci_disable_sriov(struct pci_dev *dev) +{ + might_sleep(); + + if (!dev->is_physfn) + return; + + sriov_disable(dev); +} +EXPORT_SYMBOL_GPL(pci_disable_sriov); diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index f4fc10fc5872..0f1c7d103509 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -209,6 +209,8 @@ struct pci_sriov { u32 cap; /* SR-IOV Capabilities */ u16 ctrl; /* SR-IOV Control */ u16 total; /* total VFs associated with the PF */ + u16 initial; /* initial VFs associated with the PF */ + u16 nr_virtfn; /* number of VFs available */ u16 offset; /* first VF Routing ID offset */ u16 stride; /* following VF stride */ u32 pgsz; /* page size for BAR alignment */ diff --git a/include/linux/pci.h b/include/linux/pci.h index 8ce2f2d9ab63..c2e491e04063 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -265,6 +265,7 @@ struct pci_dev { unsigned int is_pcie:1; unsigned int state_saved:1; unsigned int is_physfn:1; + unsigned int is_virtfn:1; pci_dev_flags_t dev_flags; atomic_t enable_cnt; /* pci_enable_device has been called */ @@ -279,7 +280,10 @@ struct pci_dev { #endif struct pci_vpd *vpd; #ifdef CONFIG_PCI_IOV - struct pci_sriov *sriov; /* SR-IOV capability related */ + union { + struct pci_sriov *sriov; /* SR-IOV capability related */ + struct pci_dev *physfn; /* the PF this VF is associated with */ + }; #endif }; @@ -1212,5 +1216,18 @@ int pci_ext_cfg_avail(struct pci_dev *dev); void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar); +#ifdef CONFIG_PCI_IOV +extern int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn); +extern void pci_disable_sriov(struct pci_dev *dev); +#else +static inline int pci_enable_sriov(struct pci_dev *dev, int nr_virtfn) +{ + return -ENODEV; +} +static inline void pci_disable_sriov(struct pci_dev *dev) +{ +} +#endif + #endif /* __KERNEL__ */ #endif /* LINUX_PCI_H */ -- 2.34.1