diff options
Diffstat (limited to 'drivers/xen/xen-pciback/controller.c')
-rw-r--r-- | drivers/xen/xen-pciback/controller.c | 442 |
1 files changed, 442 insertions, 0 deletions
diff --git a/drivers/xen/xen-pciback/controller.c b/drivers/xen/xen-pciback/controller.c new file mode 100644 index 000000000000..7f04f116daec --- /dev/null +++ b/drivers/xen/xen-pciback/controller.c @@ -0,0 +1,442 @@ +/* + * Copyright (C) 2007 Hewlett-Packard Development Company, L.P. + * Alex Williamson <alex.williamson@hp.com> + * + * PCI "Controller" Backend - virtualize PCI bus topology based on PCI + * controllers. Devices under the same PCI controller are exposed on the + * same virtual domain:bus. Within a bus, device slots are virtualized + * to compact the bus. + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + */ + +#include <linux/acpi.h> +#include <linux/list.h> +#include <linux/pci.h> +#include <linux/spinlock.h> +#include "pciback.h" + +#define PCI_MAX_BUSSES 255 +#define PCI_MAX_SLOTS 32 + +struct controller_dev_entry { + struct list_head list; + struct pci_dev *dev; + unsigned int devfn; +}; + +struct controller_list_entry { + struct list_head list; + struct pci_controller *controller; + unsigned int domain; + unsigned int bus; + unsigned int next_devfn; + struct list_head dev_list; +}; + +struct controller_dev_data { + struct list_head list; + unsigned int next_domain; + unsigned int next_bus; + spinlock_t lock; +}; + +struct walk_info { + struct pciback_device *pdev; + int resource_count; + int root_num; +}; + +struct pci_dev *pciback_get_pci_dev(struct pciback_device *pdev, + unsigned int domain, unsigned int bus, + unsigned int devfn) +{ + struct controller_dev_data *dev_data = pdev->pci_dev_data; + struct controller_dev_entry *dev_entry; + struct controller_list_entry *cntrl_entry; + struct pci_dev *dev = NULL; + unsigned long flags; + + spin_lock_irqsave(&dev_data->lock, flags); + + list_for_each_entry(cntrl_entry, &dev_data->list, list) { + if (cntrl_entry->domain != domain || + cntrl_entry->bus != bus) + continue; + + list_for_each_entry(dev_entry, &cntrl_entry->dev_list, list) { + if (devfn == dev_entry->devfn) { + dev = dev_entry->dev; + goto found; + } + } + } +found: + spin_unlock_irqrestore(&dev_data->lock, flags); + + return dev; +} + +int pciback_add_pci_dev(struct pciback_device *pdev, struct pci_dev *dev, + int devid, publish_pci_dev_cb publish_cb) +{ + struct controller_dev_data *dev_data = pdev->pci_dev_data; + struct controller_dev_entry *dev_entry; + struct controller_list_entry *cntrl_entry; + struct pci_controller *dev_controller = PCI_CONTROLLER(dev); + unsigned long flags; + int ret = 0, found = 0; + + spin_lock_irqsave(&dev_data->lock, flags); + + /* Look to see if we already have a domain:bus for this controller */ + list_for_each_entry(cntrl_entry, &dev_data->list, list) { + if (cntrl_entry->controller == dev_controller) { + found = 1; + break; + } + } + + if (!found) { + cntrl_entry = kmalloc(sizeof(*cntrl_entry), GFP_ATOMIC); + if (!cntrl_entry) { + ret = -ENOMEM; + goto out; + } + + cntrl_entry->controller = dev_controller; + cntrl_entry->next_devfn = PCI_DEVFN(0, 0); + + cntrl_entry->domain = dev_data->next_domain; + cntrl_entry->bus = dev_data->next_bus++; + if (dev_data->next_bus > PCI_MAX_BUSSES) { + dev_data->next_domain++; + dev_data->next_bus = 0; + } + + INIT_LIST_HEAD(&cntrl_entry->dev_list); + + list_add_tail(&cntrl_entry->list, &dev_data->list); + } + + if (PCI_SLOT(cntrl_entry->next_devfn) > PCI_MAX_SLOTS) { + /* + * While it seems unlikely, this can actually happen if + * a controller has P2P bridges under it. + */ + xenbus_dev_fatal(pdev->xdev, -ENOSPC, "Virtual bus %04x:%02x " + "is full, no room to export %04x:%02x:%02x.%x", + cntrl_entry->domain, cntrl_entry->bus, + pci_domain_nr(dev->bus), dev->bus->number, + PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn)); + ret = -ENOSPC; + goto out; + } + + dev_entry = kmalloc(sizeof(*dev_entry), GFP_ATOMIC); + if (!dev_entry) { + if (list_empty(&cntrl_entry->dev_list)) { + list_del(&cntrl_entry->list); + kfree(cntrl_entry); + } + ret = -ENOMEM; + goto out; + } + + dev_entry->dev = dev; + dev_entry->devfn = cntrl_entry->next_devfn; + + list_add_tail(&dev_entry->list, &cntrl_entry->dev_list); + + cntrl_entry->next_devfn += PCI_DEVFN(1, 0); + +out: + spin_unlock_irqrestore(&dev_data->lock, flags); + + /* TODO: Publish virtual domain:bus:slot.func here. */ + + return ret; +} + +void pciback_release_pci_dev(struct pciback_device *pdev, struct pci_dev *dev) +{ + struct controller_dev_data *dev_data = pdev->pci_dev_data; + struct controller_list_entry *cntrl_entry; + struct controller_dev_entry *dev_entry = NULL; + struct pci_dev *found_dev = NULL; + unsigned long flags; + + spin_lock_irqsave(&dev_data->lock, flags); + + list_for_each_entry(cntrl_entry, &dev_data->list, list) { + if (cntrl_entry->controller != PCI_CONTROLLER(dev)) + continue; + + list_for_each_entry(dev_entry, &cntrl_entry->dev_list, list) { + if (dev_entry->dev == dev) { + found_dev = dev_entry->dev; + break; + } + } + } + + if (!found_dev) { + spin_unlock_irqrestore(&dev_data->lock, flags); + return; + } + + list_del(&dev_entry->list); + kfree(dev_entry); + + if (list_empty(&cntrl_entry->dev_list)) { + list_del(&cntrl_entry->list); + kfree(cntrl_entry); + } + + spin_unlock_irqrestore(&dev_data->lock, flags); + pcistub_put_pci_dev(found_dev); +} + +int pciback_init_devices(struct pciback_device *pdev) +{ + struct controller_dev_data *dev_data; + + dev_data = kmalloc(sizeof(*dev_data), GFP_KERNEL); + if (!dev_data) + return -ENOMEM; + + spin_lock_init(&dev_data->lock); + + INIT_LIST_HEAD(&dev_data->list); + + /* Starting domain:bus numbers */ + dev_data->next_domain = 0; + dev_data->next_bus = 0; + + pdev->pci_dev_data = dev_data; + + return 0; +} + +static acpi_status write_xenbus_resource(struct acpi_resource *res, void *data) +{ + struct walk_info *info = data; + struct acpi_resource_address64 addr; + acpi_status status; + int i, len, err; + char str[32], tmp[3]; + unsigned char *ptr, *buf; + + status = acpi_resource_to_address64(res, &addr); + + /* Do we care about this range? Let's check. */ + if (!ACPI_SUCCESS(status) || + !(addr.resource_type == ACPI_MEMORY_RANGE || + addr.resource_type == ACPI_IO_RANGE) || + !addr.address_length || addr.producer_consumer != ACPI_PRODUCER) + return AE_OK; + + /* + * Furthermore, we really only care to tell the guest about + * address ranges that require address translation of some sort. + */ + if (!(addr.resource_type == ACPI_MEMORY_RANGE && + addr.info.mem.translation) && + !(addr.resource_type == ACPI_IO_RANGE && + addr.info.io.translation)) + return AE_OK; + + /* Store the resource in xenbus for the guest */ + len = snprintf(str, sizeof(str), "root-%d-resource-%d", + info->root_num, info->resource_count); + if (unlikely(len >= (sizeof(str) - 1))) + return AE_OK; + + buf = kzalloc((sizeof(*res) * 2) + 1, GFP_KERNEL); + if (!buf) + return AE_OK; + + /* Clean out resource_source */ + res->data.address64.resource_source.index = 0xFF; + res->data.address64.resource_source.string_length = 0; + res->data.address64.resource_source.string_ptr = NULL; + + ptr = (unsigned char *)res; + + /* Turn the acpi_resource into an ASCII byte stream */ + for (i = 0; i < sizeof(*res); i++) { + snprintf(tmp, sizeof(tmp), "%02x", ptr[i]); + strncat(buf, tmp, 2); + } + + err = xenbus_printf(XBT_NIL, info->pdev->xdev->nodename, + str, "%s", buf); + + if (!err) + info->resource_count++; + + kfree(buf); + + return AE_OK; +} + +int pciback_publish_pci_roots(struct pciback_device *pdev, + publish_pci_root_cb publish_root_cb) +{ + struct controller_dev_data *dev_data = pdev->pci_dev_data; + struct controller_list_entry *cntrl_entry; + int i, root_num, len, err = 0; + unsigned int domain, bus; + char str[64]; + struct walk_info info; + + spin_lock(&dev_data->lock); + + list_for_each_entry(cntrl_entry, &dev_data->list, list) { + /* First publish all the domain:bus info */ + err = publish_root_cb(pdev, cntrl_entry->domain, + cntrl_entry->bus); + if (err) + goto out; + + /* + * Now figure out which root-%d this belongs to + * so we can associate resources with it. + */ + err = xenbus_scanf(XBT_NIL, pdev->xdev->nodename, + "root_num", "%d", &root_num); + + if (err != 1) + goto out; + + for (i = 0; i < root_num; i++) { + len = snprintf(str, sizeof(str), "root-%d", i); + if (unlikely(len >= (sizeof(str) - 1))) { + err = -ENOMEM; + goto out; + } + + err = xenbus_scanf(XBT_NIL, pdev->xdev->nodename, + str, "%x:%x", &domain, &bus); + if (err != 2) + goto out; + + /* Is this the one we just published? */ + if (domain == cntrl_entry->domain && + bus == cntrl_entry->bus) + break; + } + + if (i == root_num) + goto out; + + info.pdev = pdev; + info.resource_count = 0; + info.root_num = i; + + /* Let ACPI do the heavy lifting on decoding resources */ + acpi_walk_resources(cntrl_entry->controller->acpi_handle, + METHOD_NAME__CRS, write_xenbus_resource, + &info); + + /* No resouces. OK. On to the next one */ + if (!info.resource_count) + continue; + + /* Store the number of resources we wrote for this root-%d */ + len = snprintf(str, sizeof(str), "root-%d-resources", i); + if (unlikely(len >= (sizeof(str) - 1))) { + err = -ENOMEM; + goto out; + } + + err = xenbus_printf(XBT_NIL, pdev->xdev->nodename, str, + "%d", info.resource_count); + if (err) + goto out; + } + + /* Finally, write some magic to synchronize with the guest. */ + len = snprintf(str, sizeof(str), "root-resource-magic"); + if (unlikely(len >= (sizeof(str) - 1))) { + err = -ENOMEM; + goto out; + } + + err = xenbus_printf(XBT_NIL, pdev->xdev->nodename, str, + "%lx", (sizeof(struct acpi_resource) * 2) + 1); + +out: + spin_unlock(&dev_data->lock); + + return err; +} + +void pciback_release_devices(struct pciback_device *pdev) +{ + struct controller_dev_data *dev_data = pdev->pci_dev_data; + struct controller_list_entry *cntrl_entry, *c; + struct controller_dev_entry *dev_entry, *d; + + list_for_each_entry_safe(cntrl_entry, c, &dev_data->list, list) { + list_for_each_entry_safe(dev_entry, d, + &cntrl_entry->dev_list, list) { + list_del(&dev_entry->list); + pcistub_put_pci_dev(dev_entry->dev); + kfree(dev_entry); + } + list_del(&cntrl_entry->list); + kfree(cntrl_entry); + } + + kfree(dev_data); + pdev->pci_dev_data = NULL; +} + +int pciback_get_pcifront_dev(struct pci_dev *pcidev, + struct pciback_device *pdev, + unsigned int *domain, unsigned int *bus, unsigned int *devfn) +{ + struct controller_dev_data *dev_data = pdev->pci_dev_data; + struct controller_dev_entry *dev_entry; + struct controller_list_entry *cntrl_entry; + unsigned long flags; + int found = 0; + spin_lock_irqsave(&dev_data->lock, flags); + + list_for_each_entry(cntrl_entry, &dev_data->list, list) { + list_for_each_entry(dev_entry, &cntrl_entry->dev_list, list) { + if ((dev_entry->dev->bus->number == + pcidev->bus->number) && + (dev_entry->dev->devfn == + pcidev->devfn) && + (pci_domain_nr(dev_entry->dev->bus) == + pci_domain_nr(pcidev->bus))) { + found = 1; + *domain = cntrl_entry->domain; + *bus = cntrl_entry->bus; + *devfn = dev_entry->devfn; + goto out; + } + } + } +out: + spin_unlock_irqrestore(&dev_data->lock, flags); + return found; + +} + |