| /* |
| * drivers/pci/iov.c |
| * |
| * Copyright (C) 2009 Intel Corporation, Yu Zhao <yu.zhao@intel.com> |
| * |
| * PCI Express I/O Virtualization (IOV) support. |
| * Single Root IOV 1.0 |
| */ |
| |
| #include <linux/pci.h> |
| #include <linux/mutex.h> |
| #include <linux/string.h> |
| #include <linux/delay.h> |
| #include "pci.h" |
| |
| #define VIRTFN_ID_LEN 16 |
| |
| static inline u8 virtfn_bus(struct pci_dev *dev, int id) |
| { |
| return dev->bus->number + ((dev->devfn + dev->sriov->offset + |
| dev->sriov->stride * id) >> 8); |
| } |
| |
| static inline u8 virtfn_devfn(struct pci_dev *dev, int id) |
| { |
| return (dev->devfn + dev->sriov->offset + |
| 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_migration(struct pci_dev *dev) |
| { |
| u16 status; |
| struct pci_sriov *iov = dev->sriov; |
| |
| if (!iov->nr_virtfn) |
| return 0; |
| |
| if (!(iov->cap & PCI_SRIOV_CAP_VFM)) |
| return 0; |
| |
| pci_read_config_word(dev, iov->pos + PCI_SRIOV_STATUS, &status); |
| if (!(status & PCI_SRIOV_STATUS_VFM)) |
| return 0; |
| |
| schedule_work(&iov->mtask); |
| |
| return 1; |
| } |
| |
| static void sriov_migration_task(struct work_struct *work) |
| { |
| int i; |
| u8 state; |
| u16 status; |
| struct pci_sriov *iov = container_of(work, struct pci_sriov, mtask); |
| |
| for (i = iov->initial; i < iov->nr_virtfn; i++) { |
| state = readb(iov->mstate + i); |
| if (state == PCI_SRIOV_VFM_MI) { |
| writeb(PCI_SRIOV_VFM_AV, iov->mstate + i); |
| state = readb(iov->mstate + i); |
| if (state == PCI_SRIOV_VFM_AV) |
| virtfn_add(iov->self, i, 1); |
| } else if (state == PCI_SRIOV_VFM_MO) { |
| virtfn_remove(iov->self, i, 1); |
| writeb(PCI_SRIOV_VFM_UA, iov->mstate + i); |
| state = readb(iov->mstate + i); |
| if (state == PCI_SRIOV_VFM_AV) |
| virtfn_add(iov->self, i, 0); |
| } |
| } |
| |
| pci_read_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, &status); |
| status &= ~PCI_SRIOV_STATUS_VFM; |
| pci_write_config_word(iov->self, iov->pos + PCI_SRIOV_STATUS, status); |
| } |
| |
| static int sriov_enable_migration(struct pci_dev *dev, int nr_virtfn) |
| { |
| int bir; |
| u32 table; |
| resource_size_t pa; |
| struct pci_sriov *iov = dev->sriov; |
| |
| if (nr_virtfn <= iov->initial) |
| return 0; |
| |
| pci_read_config_dword(dev, iov->pos + PCI_SRIOV_VFM, &table); |
| bir = PCI_SRIOV_VFM_BIR(table); |
| if (bir > PCI_STD_RESOURCE_END) |
| return -EIO; |
| |
| table = PCI_SRIOV_VFM_OFFSET(table); |
| if (table + nr_virtfn > pci_resource_len(dev, bir)) |
| return -EIO; |
| |
| pa = pci_resource_start(dev, bir) + table; |
| iov->mstate = ioremap(pa, nr_virtfn); |
| if (!iov->mstate) |
| return -ENOMEM; |
| |
| INIT_WORK(&iov->mtask, sriov_migration_task); |
| |
| iov->ctrl |= PCI_SRIOV_CTRL_VFM | PCI_SRIOV_CTRL_INTR; |
| pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); |
| |
| return 0; |
| } |
| |
| static void sriov_disable_migration(struct pci_dev *dev) |
| { |
| struct pci_sriov *iov = dev->sriov; |
| |
| iov->ctrl &= ~(PCI_SRIOV_CTRL_VFM | PCI_SRIOV_CTRL_INTR); |
| pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); |
| |
| cancel_work_sync(&iov->mtask); |
| iounmap(iov->mstate); |
| } |
| |
| 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; |
| } |
| |
| if (iov->cap & PCI_SRIOV_CAP_VFM) { |
| rc = sriov_enable_migration(dev, nr_virtfn); |
| 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; |
| |
| if (iov->cap & PCI_SRIOV_CAP_VFM) |
| sriov_disable_migration(dev); |
| |
| 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; |
| int rc; |
| int nres; |
| u32 pgsz; |
| u16 ctrl, total, offset, stride; |
| struct pci_sriov *iov; |
| struct resource *res; |
| struct pci_dev *pdev; |
| |
| if (dev->pcie_type != PCI_EXP_TYPE_RC_END && |
| dev->pcie_type != PCI_EXP_TYPE_ENDPOINT) |
| return -ENODEV; |
| |
| pci_read_config_word(dev, pos + PCI_SRIOV_CTRL, &ctrl); |
| if (ctrl & PCI_SRIOV_CTRL_VFE) { |
| pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0); |
| ssleep(1); |
| } |
| |
| pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total); |
| if (!total) |
| return 0; |
| |
| ctrl = 0; |
| list_for_each_entry(pdev, &dev->bus->devices, bus_list) |
| if (pdev->is_physfn) |
| goto found; |
| |
| pdev = NULL; |
| if (pci_ari_enabled(dev->bus)) |
| ctrl |= PCI_SRIOV_CTRL_ARI; |
| |
| found: |
| pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, ctrl); |
| pci_write_config_word(dev, pos + PCI_SRIOV_NUM_VF, total); |
| pci_read_config_word(dev, pos + PCI_SRIOV_VF_OFFSET, &offset); |
| pci_read_config_word(dev, pos + PCI_SRIOV_VF_STRIDE, &stride); |
| if (!offset || (total > 1 && !stride)) |
| return -EIO; |
| |
| pci_read_config_dword(dev, pos + PCI_SRIOV_SUP_PGSIZE, &pgsz); |
| i = PAGE_SHIFT > 12 ? PAGE_SHIFT - 12 : 0; |
| pgsz &= ~((1 << i) - 1); |
| if (!pgsz) |
| return -EIO; |
| |
| pgsz &= ~(pgsz - 1); |
| pci_write_config_dword(dev, pos + PCI_SRIOV_SYS_PGSIZE, pgsz); |
| |
| nres = 0; |
| for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { |
| res = dev->resource + PCI_IOV_RESOURCES + i; |
| i += __pci_read_base(dev, pci_bar_unknown, res, |
| pos + PCI_SRIOV_BAR + i * 4); |
| if (!res->flags) |
| continue; |
| if (resource_size(res) & (PAGE_SIZE - 1)) { |
| rc = -EIO; |
| goto failed; |
| } |
| res->end = res->start + resource_size(res) * total - 1; |
| nres++; |
| } |
| |
| iov = kzalloc(sizeof(*iov), GFP_KERNEL); |
| if (!iov) { |
| rc = -ENOMEM; |
| goto failed; |
| } |
| |
| iov->pos = pos; |
| iov->nres = nres; |
| iov->ctrl = ctrl; |
| iov->total = total; |
| iov->offset = offset; |
| iov->stride = stride; |
| iov->pgsz = pgsz; |
| iov->self = dev; |
| pci_read_config_dword(dev, pos + PCI_SRIOV_CAP, &iov->cap); |
| pci_read_config_byte(dev, pos + PCI_SRIOV_FUNC_LINK, &iov->link); |
| |
| if (pdev) |
| iov->dev = pci_dev_get(pdev); |
| else { |
| iov->dev = dev; |
| mutex_init(&iov->lock); |
| } |
| |
| dev->sriov = iov; |
| dev->is_physfn = 1; |
| |
| return 0; |
| |
| failed: |
| for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) { |
| res = dev->resource + PCI_IOV_RESOURCES + i; |
| res->flags = 0; |
| } |
| |
| return rc; |
| } |
| |
| 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 |
| pci_dev_put(dev->sriov->dev); |
| |
| kfree(dev->sriov); |
| dev->sriov = NULL; |
| } |
| |
| static void sriov_restore_state(struct pci_dev *dev) |
| { |
| int i; |
| u16 ctrl; |
| struct pci_sriov *iov = dev->sriov; |
| |
| pci_read_config_word(dev, iov->pos + PCI_SRIOV_CTRL, &ctrl); |
| if (ctrl & PCI_SRIOV_CTRL_VFE) |
| return; |
| |
| for (i = PCI_IOV_RESOURCES; i <= PCI_IOV_RESOURCE_END; i++) |
| 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); |
| } |
| |
| /** |
| * pci_iov_init - initialize the IOV capability |
| * @dev: the PCI device |
| * |
| * Returns 0 on success, or negative on failure. |
| */ |
| int pci_iov_init(struct pci_dev *dev) |
| { |
| int pos; |
| |
| if (!dev->is_pcie) |
| return -ENODEV; |
| |
| pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_SRIOV); |
| if (pos) |
| return sriov_init(dev, pos); |
| |
| return -ENODEV; |
| } |
| |
| /** |
| * pci_iov_release - release resources used by the IOV capability |
| * @dev: the PCI device |
| */ |
| void pci_iov_release(struct pci_dev *dev) |
| { |
| if (dev->is_physfn) |
| sriov_release(dev); |
| } |
| |
| /** |
| * pci_iov_resource_bar - get position of the SR-IOV BAR |
| * @dev: the PCI device |
| * @resno: the resource number |
| * @type: the BAR type to be filled in |
| * |
| * Returns position of the BAR encapsulated in the SR-IOV capability. |
| */ |
| int pci_iov_resource_bar(struct pci_dev *dev, int resno, |
| enum pci_bar_type *type) |
| { |
| if (resno < PCI_IOV_RESOURCES || resno > PCI_IOV_RESOURCE_END) |
| return 0; |
| |
| BUG_ON(!dev->is_physfn); |
| |
| *type = pci_bar_unknown; |
| |
| return dev->sriov->pos + PCI_SRIOV_BAR + |
| 4 * (resno - PCI_IOV_RESOURCES); |
| } |
| |
| /** |
| * pci_restore_iov_state - restore the state of the IOV capability |
| * @dev: the PCI device |
| */ |
| void pci_restore_iov_state(struct pci_dev *dev) |
| { |
| if (dev->is_physfn) |
| sriov_restore_state(dev); |
| } |
| |
| /** |
| * pci_iov_bus_range - find bus range used by Virtual Function |
| * @bus: the PCI bus |
| * |
| * Returns max number of buses (exclude current one) used by Virtual |
| * Functions. |
| */ |
| int pci_iov_bus_range(struct pci_bus *bus) |
| { |
| int max = 0; |
| u8 busnr; |
| struct pci_dev *dev; |
| |
| list_for_each_entry(dev, &bus->devices, bus_list) { |
| if (!dev->is_physfn) |
| continue; |
| busnr = virtfn_bus(dev, dev->sriov->total - 1); |
| if (busnr > max) |
| max = busnr; |
| } |
| |
| 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); |
| |
| /** |
| * pci_sriov_migration - notify SR-IOV core of Virtual Function Migration |
| * @dev: the PCI device |
| * |
| * Returns IRQ_HANDLED if the IRQ is handled, or IRQ_NONE if not. |
| * |
| * Physical Function driver is responsible to register IRQ handler using |
| * VF Migration Interrupt Message Number, and call this function when the |
| * interrupt is generated by the hardware. |
| */ |
| irqreturn_t pci_sriov_migration(struct pci_dev *dev) |
| { |
| if (!dev->is_physfn) |
| return IRQ_NONE; |
| |
| return sriov_migration(dev) ? IRQ_HANDLED : IRQ_NONE; |
| } |
| EXPORT_SYMBOL_GPL(pci_sriov_migration); |