diff options
Diffstat (limited to 'drivers/xen/xen-pciback/pci_stub.c')
| -rw-r--r-- | drivers/xen/xen-pciback/pci_stub.c | 1652 |
1 files changed, 1652 insertions, 0 deletions
diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c new file mode 100644 index 000000000..adf3aae29 --- /dev/null +++ b/drivers/xen/xen-pciback/pci_stub.c @@ -0,0 +1,1652 @@ +/* + * PCI Stub Driver - Grabs devices in backend to be exported later + * + * Ryan Wilson <hap9@epoch.ncsc.mil> + * Chris Bookholt <hap10@epoch.ncsc.mil> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/rwsem.h> +#include <linux/list.h> +#include <linux/spinlock.h> +#include <linux/kref.h> +#include <linux/pci.h> +#include <linux/wait.h> +#include <linux/sched.h> +#include <linux/atomic.h> +#include <xen/events.h> +#include <asm/xen/pci.h> +#include <asm/xen/hypervisor.h> +#include <xen/interface/physdev.h> +#include "pciback.h" +#include "conf_space.h" +#include "conf_space_quirks.h" + +#define PCISTUB_DRIVER_NAME "pciback" + +static char *pci_devs_to_hide; +wait_queue_head_t xen_pcibk_aer_wait_queue; +/*Add sem for sync AER handling and xen_pcibk remove/reconfigue ops, +* We want to avoid in middle of AER ops, xen_pcibk devices is being removed +*/ +static DECLARE_RWSEM(pcistub_sem); +module_param_named(hide, pci_devs_to_hide, charp, 0444); + +struct pcistub_device_id { + struct list_head slot_list; + int domain; + unsigned char bus; + unsigned int devfn; +}; +static LIST_HEAD(pcistub_device_ids); +static DEFINE_SPINLOCK(device_ids_lock); + +struct pcistub_device { + struct kref kref; + struct list_head dev_list; + spinlock_t lock; + + struct pci_dev *dev; + struct xen_pcibk_device *pdev;/* non-NULL if struct pci_dev is in use */ +}; + +/* Access to pcistub_devices & seized_devices lists and the initialize_devices + * flag must be locked with pcistub_devices_lock + */ +static DEFINE_SPINLOCK(pcistub_devices_lock); +static LIST_HEAD(pcistub_devices); + +/* wait for device_initcall before initializing our devices + * (see pcistub_init_devices_late) + */ +static int initialize_devices; +static LIST_HEAD(seized_devices); + +static struct pcistub_device *pcistub_device_alloc(struct pci_dev *dev) +{ + struct pcistub_device *psdev; + + dev_dbg(&dev->dev, "pcistub_device_alloc\n"); + + psdev = kzalloc(sizeof(*psdev), GFP_KERNEL); + if (!psdev) + return NULL; + + psdev->dev = pci_dev_get(dev); + if (!psdev->dev) { + kfree(psdev); + return NULL; + } + + kref_init(&psdev->kref); + spin_lock_init(&psdev->lock); + + return psdev; +} + +/* Don't call this directly as it's called by pcistub_device_put */ +static void pcistub_device_release(struct kref *kref) +{ + struct pcistub_device *psdev; + struct pci_dev *dev; + struct xen_pcibk_dev_data *dev_data; + + psdev = container_of(kref, struct pcistub_device, kref); + dev = psdev->dev; + dev_data = pci_get_drvdata(dev); + + dev_dbg(&dev->dev, "pcistub_device_release\n"); + + xen_unregister_device_domain_owner(dev); + + /* Call the reset function which does not take lock as this + * is called from "unbind" which takes a device_lock mutex. + */ + __pci_reset_function_locked(dev); + if (dev_data && + pci_load_and_free_saved_state(dev, &dev_data->pci_saved_state)) + dev_info(&dev->dev, "Could not reload PCI state\n"); + else + pci_restore_state(dev); + + if (dev->msix_cap) { + struct physdev_pci_device ppdev = { + .seg = pci_domain_nr(dev->bus), + .bus = dev->bus->number, + .devfn = dev->devfn + }; + int err = HYPERVISOR_physdev_op(PHYSDEVOP_release_msix, + &ppdev); + + if (err && err != -ENOSYS) + dev_warn(&dev->dev, "MSI-X release failed (%d)\n", + err); + } + + /* Disable the device */ + xen_pcibk_reset_device(dev); + + kfree(dev_data); + pci_set_drvdata(dev, NULL); + + /* Clean-up the device */ + xen_pcibk_config_free_dyn_fields(dev); + xen_pcibk_config_free_dev(dev); + + pci_clear_dev_assigned(dev); + pci_dev_put(dev); + + kfree(psdev); +} + +static inline void pcistub_device_get(struct pcistub_device *psdev) +{ + kref_get(&psdev->kref); +} + +static inline void pcistub_device_put(struct pcistub_device *psdev) +{ + kref_put(&psdev->kref, pcistub_device_release); +} + +static struct pcistub_device *pcistub_device_find_locked(int domain, int bus, + int slot, int func) +{ + struct pcistub_device *psdev; + + list_for_each_entry(psdev, &pcistub_devices, dev_list) { + if (psdev->dev != NULL + && domain == pci_domain_nr(psdev->dev->bus) + && bus == psdev->dev->bus->number + && slot == PCI_SLOT(psdev->dev->devfn) + && func == PCI_FUNC(psdev->dev->devfn)) { + return psdev; + } + } + + return NULL; +} + +static struct pcistub_device *pcistub_device_find(int domain, int bus, + int slot, int func) +{ + struct pcistub_device *psdev; + unsigned long flags; + + spin_lock_irqsave(&pcistub_devices_lock, flags); + + psdev = pcistub_device_find_locked(domain, bus, slot, func); + if (psdev) + pcistub_device_get(psdev); + + spin_unlock_irqrestore(&pcistub_devices_lock, flags); + return psdev; +} + +static struct pci_dev *pcistub_device_get_pci_dev(struct xen_pcibk_device *pdev, + struct pcistub_device *psdev) +{ + struct pci_dev *pci_dev = NULL; + unsigned long flags; + + pcistub_device_get(psdev); + + spin_lock_irqsave(&psdev->lock, flags); + if (!psdev->pdev) { + psdev->pdev = pdev; + pci_dev = psdev->dev; + } + spin_unlock_irqrestore(&psdev->lock, flags); + + if (!pci_dev) + pcistub_device_put(psdev); + + return pci_dev; +} + +struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev, + int domain, int bus, + int slot, int func) +{ + struct pcistub_device *psdev; + struct pci_dev *found_dev = NULL; + unsigned long flags; + + spin_lock_irqsave(&pcistub_devices_lock, flags); + + psdev = pcistub_device_find_locked(domain, bus, slot, func); + if (psdev) + found_dev = pcistub_device_get_pci_dev(pdev, psdev); + + spin_unlock_irqrestore(&pcistub_devices_lock, flags); + return found_dev; +} + +struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev, + struct pci_dev *dev) +{ + struct pcistub_device *psdev; + struct pci_dev *found_dev = NULL; + unsigned long flags; + + spin_lock_irqsave(&pcistub_devices_lock, flags); + + list_for_each_entry(psdev, &pcistub_devices, dev_list) { + if (psdev->dev == dev) { + found_dev = pcistub_device_get_pci_dev(pdev, psdev); + break; + } + } + + spin_unlock_irqrestore(&pcistub_devices_lock, flags); + return found_dev; +} + +/* + * Called when: + * - XenBus state has been reconfigure (pci unplug). See xen_pcibk_remove_device + * - XenBus state has been disconnected (guest shutdown). See xen_pcibk_xenbus_remove + * - 'echo BDF > unbind' on pciback module with no guest attached. See pcistub_remove + * - 'echo BDF > unbind' with a guest still using it. See pcistub_remove + * + * As such we have to be careful. + * + * To make this easier, the caller has to hold the device lock. + */ +void pcistub_put_pci_dev(struct pci_dev *dev) +{ + struct pcistub_device *psdev, *found_psdev = NULL; + unsigned long flags; + struct xen_pcibk_dev_data *dev_data; + int ret; + + spin_lock_irqsave(&pcistub_devices_lock, flags); + + list_for_each_entry(psdev, &pcistub_devices, dev_list) { + if (psdev->dev == dev) { + found_psdev = psdev; + break; + } + } + + spin_unlock_irqrestore(&pcistub_devices_lock, flags); + if (WARN_ON(!found_psdev)) + return; + + /*hold this lock for avoiding breaking link between + * pcistub and xen_pcibk when AER is in processing + */ + down_write(&pcistub_sem); + /* Cleanup our device + * (so it's ready for the next domain) + */ + device_lock_assert(&dev->dev); + __pci_reset_function_locked(dev); + + dev_data = pci_get_drvdata(dev); + ret = pci_load_saved_state(dev, dev_data->pci_saved_state); + if (!ret) { + /* + * The usual sequence is pci_save_state & pci_restore_state + * but the guest might have messed the configuration space up. + * Use the initial version (when device was bound to us). + */ + pci_restore_state(dev); + } else + dev_info(&dev->dev, "Could not reload PCI state\n"); + /* This disables the device. */ + xen_pcibk_reset_device(dev); + + /* And cleanup up our emulated fields. */ + xen_pcibk_config_reset_dev(dev); + xen_pcibk_config_free_dyn_fields(dev); + + xen_unregister_device_domain_owner(dev); + + spin_lock_irqsave(&found_psdev->lock, flags); + found_psdev->pdev = NULL; + spin_unlock_irqrestore(&found_psdev->lock, flags); + + pcistub_device_put(found_psdev); + up_write(&pcistub_sem); +} + +static int pcistub_match_one(struct pci_dev *dev, + struct pcistub_device_id *pdev_id) +{ + /* Match the specified device by domain, bus, slot, func and also if + * any of the device's parent bridges match. + */ + for (; dev != NULL; dev = dev->bus->self) { + if (pci_domain_nr(dev->bus) == pdev_id->domain + && dev->bus->number == pdev_id->bus + && dev->devfn == pdev_id->devfn) + return 1; + + /* Sometimes topmost bridge links to itself. */ + if (dev == dev->bus->self) + break; + } + + return 0; +} + +static int pcistub_match(struct pci_dev *dev) +{ + struct pcistub_device_id *pdev_id; + unsigned long flags; + int found = 0; + + spin_lock_irqsave(&device_ids_lock, flags); + list_for_each_entry(pdev_id, &pcistub_device_ids, slot_list) { + if (pcistub_match_one(dev, pdev_id)) { + found = 1; + break; + } + } + spin_unlock_irqrestore(&device_ids_lock, flags); + + return found; +} + +static int pcistub_init_device(struct pci_dev *dev) +{ + struct xen_pcibk_dev_data *dev_data; + int err = 0; + + dev_dbg(&dev->dev, "initializing...\n"); + + /* The PCI backend is not intended to be a module (or to work with + * removable PCI devices (yet). If it were, xen_pcibk_config_free() + * would need to be called somewhere to free the memory allocated + * here and then to call kfree(pci_get_drvdata(psdev->dev)). + */ + dev_data = kzalloc(sizeof(*dev_data) + strlen(DRV_NAME "[]") + + strlen(pci_name(dev)) + 1, GFP_KERNEL); + if (!dev_data) { + err = -ENOMEM; + goto out; + } + pci_set_drvdata(dev, dev_data); + + /* + * Setup name for fake IRQ handler. It will only be enabled + * once the device is turned on by the guest. + */ + sprintf(dev_data->irq_name, DRV_NAME "[%s]", pci_name(dev)); + + dev_dbg(&dev->dev, "initializing config\n"); + + init_waitqueue_head(&xen_pcibk_aer_wait_queue); + err = xen_pcibk_config_init_dev(dev); + if (err) + goto out; + + /* HACK: Force device (& ACPI) to determine what IRQ it's on - we + * must do this here because pcibios_enable_device may specify + * the pci device's true irq (and possibly its other resources) + * if they differ from what's in the configuration space. + * This makes the assumption that the device's resources won't + * change after this point (otherwise this code may break!) + */ + dev_dbg(&dev->dev, "enabling device\n"); + err = pci_enable_device(dev); + if (err) + goto config_release; + + if (dev->msix_cap) { + struct physdev_pci_device ppdev = { + .seg = pci_domain_nr(dev->bus), + .bus = dev->bus->number, + .devfn = dev->devfn + }; + + err = HYPERVISOR_physdev_op(PHYSDEVOP_prepare_msix, &ppdev); + if (err && err != -ENOSYS) + dev_err(&dev->dev, "MSI-X preparation failed (%d)\n", + err); + } + + /* We need the device active to save the state. */ + dev_dbg(&dev->dev, "save state of device\n"); + pci_save_state(dev); + dev_data->pci_saved_state = pci_store_saved_state(dev); + if (!dev_data->pci_saved_state) + dev_err(&dev->dev, "Could not store PCI conf saved state!\n"); + else { + dev_dbg(&dev->dev, "resetting (FLR, D3, etc) the device\n"); + __pci_reset_function_locked(dev); + pci_restore_state(dev); + } + /* Now disable the device (this also ensures some private device + * data is setup before we export) + */ + dev_dbg(&dev->dev, "reset device\n"); + xen_pcibk_reset_device(dev); + + pci_set_dev_assigned(dev); + return 0; + +config_release: + xen_pcibk_config_free_dev(dev); + +out: + pci_set_drvdata(dev, NULL); + kfree(dev_data); + return err; +} + +/* + * Because some initialization still happens on + * devices during fs_initcall, we need to defer + * full initialization of our devices until + * device_initcall. + */ +static int __init pcistub_init_devices_late(void) +{ + struct pcistub_device *psdev; + unsigned long flags; + int err = 0; + + spin_lock_irqsave(&pcistub_devices_lock, flags); + + while (!list_empty(&seized_devices)) { + psdev = container_of(seized_devices.next, + struct pcistub_device, dev_list); + list_del(&psdev->dev_list); + + spin_unlock_irqrestore(&pcistub_devices_lock, flags); + + err = pcistub_init_device(psdev->dev); + if (err) { + dev_err(&psdev->dev->dev, + "error %d initializing device\n", err); + kfree(psdev); + psdev = NULL; + } + + spin_lock_irqsave(&pcistub_devices_lock, flags); + + if (psdev) + list_add_tail(&psdev->dev_list, &pcistub_devices); + } + + initialize_devices = 1; + + spin_unlock_irqrestore(&pcistub_devices_lock, flags); + + return 0; +} + +static void pcistub_device_id_add_list(struct pcistub_device_id *new, + int domain, int bus, unsigned int devfn) +{ + struct pcistub_device_id *pci_dev_id; + unsigned long flags; + int found = 0; + + spin_lock_irqsave(&device_ids_lock, flags); + + list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) { + if (pci_dev_id->domain == domain && pci_dev_id->bus == bus && + pci_dev_id->devfn == devfn) { + found = 1; + break; + } + } + + if (!found) { + new->domain = domain; + new->bus = bus; + new->devfn = devfn; + list_add_tail(&new->slot_list, &pcistub_device_ids); + } + + spin_unlock_irqrestore(&device_ids_lock, flags); + + if (found) + kfree(new); +} + +static int pcistub_seize(struct pci_dev *dev, + struct pcistub_device_id *pci_dev_id) +{ + struct pcistub_device *psdev; + unsigned long flags; + int err = 0; + + psdev = pcistub_device_alloc(dev); + if (!psdev) { + kfree(pci_dev_id); + return -ENOMEM; + } + + spin_lock_irqsave(&pcistub_devices_lock, flags); + + if (initialize_devices) { + spin_unlock_irqrestore(&pcistub_devices_lock, flags); + + /* don't want irqs disabled when calling pcistub_init_device */ + err = pcistub_init_device(psdev->dev); + + spin_lock_irqsave(&pcistub_devices_lock, flags); + + if (!err) + list_add(&psdev->dev_list, &pcistub_devices); + } else { + dev_dbg(&dev->dev, "deferring initialization\n"); + list_add(&psdev->dev_list, &seized_devices); + } + + spin_unlock_irqrestore(&pcistub_devices_lock, flags); + + if (err) { + kfree(pci_dev_id); + pcistub_device_put(psdev); + } else if (pci_dev_id) + pcistub_device_id_add_list(pci_dev_id, pci_domain_nr(dev->bus), + dev->bus->number, dev->devfn); + + return err; +} + +/* Called when 'bind'. This means we must _NOT_ call pci_reset_function or + * other functions that take the sysfs lock. */ +static int pcistub_probe(struct pci_dev *dev, const struct pci_device_id *id) +{ + int err = 0, match; + struct pcistub_device_id *pci_dev_id = NULL; + + dev_dbg(&dev->dev, "probing...\n"); + + match = pcistub_match(dev); + + if ((dev->driver_override && + !strcmp(dev->driver_override, PCISTUB_DRIVER_NAME)) || + match) { + + if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL + && dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) { + dev_err(&dev->dev, "can't export pci devices that " + "don't have a normal (0) or bridge (1) " + "header type!\n"); + err = -ENODEV; + goto out; + } + + if (!match) { + pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL); + if (!pci_dev_id) { + err = -ENOMEM; + goto out; + } + } + + dev_info(&dev->dev, "seizing device\n"); + err = pcistub_seize(dev, pci_dev_id); + } else + /* Didn't find the device */ + err = -ENODEV; + +out: + return err; +} + +/* Called when 'unbind'. This means we must _NOT_ call pci_reset_function or + * other functions that take the sysfs lock. */ +static void pcistub_remove(struct pci_dev *dev) +{ + struct pcistub_device *psdev, *found_psdev = NULL; + unsigned long flags; + + dev_dbg(&dev->dev, "removing\n"); + + spin_lock_irqsave(&pcistub_devices_lock, flags); + + xen_pcibk_config_quirk_release(dev); + + list_for_each_entry(psdev, &pcistub_devices, dev_list) { + if (psdev->dev == dev) { + found_psdev = psdev; + break; + } + } + + spin_unlock_irqrestore(&pcistub_devices_lock, flags); + + if (found_psdev) { + dev_dbg(&dev->dev, "found device to remove %s\n", + found_psdev->pdev ? "- in-use" : ""); + + if (found_psdev->pdev) { + int domid = xen_find_device_domain_owner(dev); + + pr_warn("****** removing device %s while still in-use by domain %d! ******\n", + pci_name(found_psdev->dev), domid); + pr_warn("****** driver domain may still access this device's i/o resources!\n"); + pr_warn("****** shutdown driver domain before binding device\n"); + pr_warn("****** to other drivers or domains\n"); + + /* N.B. This ends up calling pcistub_put_pci_dev which ends up + * doing the FLR. */ + xen_pcibk_release_pci_dev(found_psdev->pdev, + found_psdev->dev, + false /* caller holds the lock. */); + } + + spin_lock_irqsave(&pcistub_devices_lock, flags); + list_del(&found_psdev->dev_list); + spin_unlock_irqrestore(&pcistub_devices_lock, flags); + + /* the final put for releasing from the list */ + pcistub_device_put(found_psdev); + } +} + +static const struct pci_device_id pcistub_ids[] = { + { + .vendor = PCI_ANY_ID, + .device = PCI_ANY_ID, + .subvendor = PCI_ANY_ID, + .subdevice = PCI_ANY_ID, + }, + {0,}, +}; + +#define PCI_NODENAME_MAX 40 +static void kill_domain_by_device(struct pcistub_device *psdev) +{ + struct xenbus_transaction xbt; + int err; + char nodename[PCI_NODENAME_MAX]; + + BUG_ON(!psdev); + snprintf(nodename, PCI_NODENAME_MAX, "/local/domain/0/backend/pci/%d/0", + psdev->pdev->xdev->otherend_id); + +again: + err = xenbus_transaction_start(&xbt); + if (err) { + dev_err(&psdev->dev->dev, + "error %d when start xenbus transaction\n", err); + return; + } + /*PV AER handlers will set this flag*/ + xenbus_printf(xbt, nodename, "aerState" , "aerfail"); + err = xenbus_transaction_end(xbt, 0); + if (err) { + if (err == -EAGAIN) + goto again; + dev_err(&psdev->dev->dev, + "error %d when end xenbus transaction\n", err); + return; + } +} + +/* For each aer recovery step error_detected, mmio_enabled, etc, front_end and + * backend need to have cooperation. In xen_pcibk, those steps will do similar + * jobs: send service request and waiting for front_end response. +*/ +static pci_ers_result_t common_process(struct pcistub_device *psdev, + pci_channel_state_t state, int aer_cmd, + pci_ers_result_t result) +{ + pci_ers_result_t res = result; + struct xen_pcie_aer_op *aer_op; + struct xen_pcibk_device *pdev = psdev->pdev; + struct xen_pci_sharedinfo *sh_info = pdev->sh_info; + int ret; + + /*with PV AER drivers*/ + aer_op = &(sh_info->aer_op); + aer_op->cmd = aer_cmd ; + /*useful for error_detected callback*/ + aer_op->err = state; + /*pcifront_end BDF*/ + ret = xen_pcibk_get_pcifront_dev(psdev->dev, psdev->pdev, + &aer_op->domain, &aer_op->bus, &aer_op->devfn); + if (!ret) { + dev_err(&psdev->dev->dev, + DRV_NAME ": failed to get pcifront device\n"); + return PCI_ERS_RESULT_NONE; + } + wmb(); + + dev_dbg(&psdev->dev->dev, + DRV_NAME ": aer_op %x dom %x bus %x devfn %x\n", + aer_cmd, aer_op->domain, aer_op->bus, aer_op->devfn); + /*local flag to mark there's aer request, xen_pcibk callback will use + * this flag to judge whether we need to check pci-front give aer + * service ack signal + */ + set_bit(_PCIB_op_pending, (unsigned long *)&pdev->flags); + + /*It is possible that a pcifront conf_read_write ops request invokes + * the callback which cause the spurious execution of wake_up. + * Yet it is harmless and better than a spinlock here + */ + set_bit(_XEN_PCIB_active, + (unsigned long *)&sh_info->flags); + wmb(); + notify_remote_via_irq(pdev->evtchn_irq); + + /* Enable IRQ to signal "request done". */ + xen_pcibk_lateeoi(pdev, 0); + + ret = wait_event_timeout(xen_pcibk_aer_wait_queue, + !(test_bit(_XEN_PCIB_active, (unsigned long *) + &sh_info->flags)), 300*HZ); + + /* Enable IRQ for pcifront request if not already active. */ + if (!test_bit(_PDEVF_op_active, &pdev->flags)) + xen_pcibk_lateeoi(pdev, 0); + + if (!ret) { + if (test_bit(_XEN_PCIB_active, + (unsigned long *)&sh_info->flags)) { + dev_err(&psdev->dev->dev, + "pcifront aer process not responding!\n"); + clear_bit(_XEN_PCIB_active, + (unsigned long *)&sh_info->flags); + aer_op->err = PCI_ERS_RESULT_NONE; + return res; + } + } + clear_bit(_PCIB_op_pending, (unsigned long *)&pdev->flags); + + res = (pci_ers_result_t)aer_op->err; + return res; +} + +/* +* xen_pcibk_slot_reset: it will send the slot_reset request to pcifront in case +* of the device driver could provide this service, and then wait for pcifront +* ack. +* @dev: pointer to PCI devices +* return value is used by aer_core do_recovery policy +*/ +static pci_ers_result_t xen_pcibk_slot_reset(struct pci_dev *dev) +{ + struct pcistub_device *psdev; + pci_ers_result_t result; + + result = PCI_ERS_RESULT_RECOVERED; + dev_dbg(&dev->dev, "xen_pcibk_slot_reset(bus:%x,devfn:%x)\n", + dev->bus->number, dev->devfn); + + down_write(&pcistub_sem); + psdev = pcistub_device_find(pci_domain_nr(dev->bus), + dev->bus->number, + PCI_SLOT(dev->devfn), + PCI_FUNC(dev->devfn)); + + if (!psdev || !psdev->pdev) { + dev_err(&dev->dev, + DRV_NAME " device is not found/assigned\n"); + goto end; + } + + if (!psdev->pdev->sh_info) { + dev_err(&dev->dev, DRV_NAME " device is not connected or owned" + " by HVM, kill it\n"); + kill_domain_by_device(psdev); + goto end; + } + + if (!test_bit(_XEN_PCIB_AERHANDLER, + (unsigned long *)&psdev->pdev->sh_info->flags)) { + dev_err(&dev->dev, + "guest with no AER driver should have been killed\n"); + goto end; + } + result = common_process(psdev, 1, XEN_PCI_OP_aer_slotreset, result); + + if (result == PCI_ERS_RESULT_NONE || + result == PCI_ERS_RESULT_DISCONNECT) { + dev_dbg(&dev->dev, + "No AER slot_reset service or disconnected!\n"); + kill_domain_by_device(psdev); + } +end: + if (psdev) + pcistub_device_put(psdev); + up_write(&pcistub_sem); + return result; + +} + + +/*xen_pcibk_mmio_enabled: it will send the mmio_enabled request to pcifront +* in case of the device driver could provide this service, and then wait +* for pcifront ack +* @dev: pointer to PCI devices +* return value is used by aer_core do_recovery policy +*/ + +static pci_ers_result_t xen_pcibk_mmio_enabled(struct pci_dev *dev) +{ + struct pcistub_device *psdev; + pci_ers_result_t result; + + result = PCI_ERS_RESULT_RECOVERED; + dev_dbg(&dev->dev, "xen_pcibk_mmio_enabled(bus:%x,devfn:%x)\n", + dev->bus->number, dev->devfn); + + down_write(&pcistub_sem); + psdev = pcistub_device_find(pci_domain_nr(dev->bus), + dev->bus->number, + PCI_SLOT(dev->devfn), + PCI_FUNC(dev->devfn)); + + if (!psdev || !psdev->pdev) { + dev_err(&dev->dev, + DRV_NAME " device is not found/assigned\n"); + goto end; + } + + if (!psdev->pdev->sh_info) { + dev_err(&dev->dev, DRV_NAME " device is not connected or owned" + " by HVM, kill it\n"); + kill_domain_by_device(psdev); + goto end; + } + + if (!test_bit(_XEN_PCIB_AERHANDLER, + (unsigned long *)&psdev->pdev->sh_info->flags)) { + dev_err(&dev->dev, + "guest with no AER driver should have been killed\n"); + goto end; + } + result = common_process(psdev, 1, XEN_PCI_OP_aer_mmio, result); + + if (result == PCI_ERS_RESULT_NONE || + result == PCI_ERS_RESULT_DISCONNECT) { + dev_dbg(&dev->dev, + "No AER mmio_enabled service or disconnected!\n"); + kill_domain_by_device(psdev); + } +end: + if (psdev) + pcistub_device_put(psdev); + up_write(&pcistub_sem); + return result; +} + +/*xen_pcibk_error_detected: it will send the error_detected request to pcifront +* in case of the device driver could provide this service, and then wait +* for pcifront ack. +* @dev: pointer to PCI devices +* @error: the current PCI connection state +* return value is used by aer_core do_recovery policy +*/ + +static pci_ers_result_t xen_pcibk_error_detected(struct pci_dev *dev, + pci_channel_state_t error) +{ + struct pcistub_device *psdev; + pci_ers_result_t result; + + result = PCI_ERS_RESULT_CAN_RECOVER; + dev_dbg(&dev->dev, "xen_pcibk_error_detected(bus:%x,devfn:%x)\n", + dev->bus->number, dev->devfn); + + down_write(&pcistub_sem); + psdev = pcistub_device_find(pci_domain_nr(dev->bus), + dev->bus->number, + PCI_SLOT(dev->devfn), + PCI_FUNC(dev->devfn)); + + if (!psdev || !psdev->pdev) { + dev_err(&dev->dev, + DRV_NAME " device is not found/assigned\n"); + goto end; + } + + if (!psdev->pdev->sh_info) { + dev_err(&dev->dev, DRV_NAME " device is not connected or owned" + " by HVM, kill it\n"); + kill_domain_by_device(psdev); + goto end; + } + + /*Guest owns the device yet no aer handler regiested, kill guest*/ + if (!test_bit(_XEN_PCIB_AERHANDLER, + (unsigned long *)&psdev->pdev->sh_info->flags)) { + dev_dbg(&dev->dev, "guest may have no aer driver, kill it\n"); + kill_domain_by_device(psdev); + goto end; + } + result = common_process(psdev, error, XEN_PCI_OP_aer_detected, result); + + if (result == PCI_ERS_RESULT_NONE || + result == PCI_ERS_RESULT_DISCONNECT) { + dev_dbg(&dev->dev, + "No AER error_detected service or disconnected!\n"); + kill_domain_by_device(psdev); + } +end: + if (psdev) + pcistub_device_put(psdev); + up_write(&pcistub_sem); + return result; +} + +/*xen_pcibk_error_resume: it will send the error_resume request to pcifront +* in case of the device driver could provide this service, and then wait +* for pcifront ack. +* @dev: pointer to PCI devices +*/ + +static void xen_pcibk_error_resume(struct pci_dev *dev) +{ + struct pcistub_device *psdev; + + dev_dbg(&dev->dev, "xen_pcibk_error_resume(bus:%x,devfn:%x)\n", + dev->bus->number, dev->devfn); + + down_write(&pcistub_sem); + psdev = pcistub_device_find(pci_domain_nr(dev->bus), + dev->bus->number, + PCI_SLOT(dev->devfn), + PCI_FUNC(dev->devfn)); + + if (!psdev || !psdev->pdev) { + dev_err(&dev->dev, + DRV_NAME " device is not found/assigned\n"); + goto end; + } + + if (!psdev->pdev->sh_info) { + dev_err(&dev->dev, DRV_NAME " device is not connected or owned" + " by HVM, kill it\n"); + kill_domain_by_device(psdev); + goto end; + } + + if (!test_bit(_XEN_PCIB_AERHANDLER, + (unsigned long *)&psdev->pdev->sh_info->flags)) { + dev_err(&dev->dev, + "guest with no AER driver should have been killed\n"); + kill_domain_by_device(psdev); + goto end; + } + common_process(psdev, 1, XEN_PCI_OP_aer_resume, + PCI_ERS_RESULT_RECOVERED); +end: + if (psdev) + pcistub_device_put(psdev); + up_write(&pcistub_sem); + return; +} + +/*add xen_pcibk AER handling*/ +static const struct pci_error_handlers xen_pcibk_error_handler = { + .error_detected = xen_pcibk_error_detected, + .mmio_enabled = xen_pcibk_mmio_enabled, + .slot_reset = xen_pcibk_slot_reset, + .resume = xen_pcibk_error_resume, +}; + +/* + * Note: There is no MODULE_DEVICE_TABLE entry here because this isn't + * for a normal device. I don't want it to be loaded automatically. + */ + +static struct pci_driver xen_pcibk_pci_driver = { + /* The name should be xen_pciback, but until the tools are updated + * we will keep it as pciback. */ + .name = PCISTUB_DRIVER_NAME, + .id_table = pcistub_ids, + .probe = pcistub_probe, + .remove = pcistub_remove, + .err_handler = &xen_pcibk_error_handler, +}; + +static inline int str_to_slot(const char *buf, int *domain, int *bus, + int *slot, int *func) +{ + int parsed = 0; + + switch (sscanf(buf, " %x:%x:%x.%x %n", domain, bus, slot, func, + &parsed)) { + case 3: + *func = -1; + sscanf(buf, " %x:%x:%x.* %n", domain, bus, slot, &parsed); + break; + case 2: + *slot = *func = -1; + sscanf(buf, " %x:%x:*.* %n", domain, bus, &parsed); + break; + } + if (parsed && !buf[parsed]) + return 0; + + /* try again without domain */ + *domain = 0; + switch (sscanf(buf, " %x:%x.%x %n", bus, slot, func, &parsed)) { + case 2: + *func = -1; + sscanf(buf, " %x:%x.* %n", bus, slot, &parsed); + break; + case 1: + *slot = *func = -1; + sscanf(buf, " %x:*.* %n", bus, &parsed); + break; + } + if (parsed && !buf[parsed]) + return 0; + + return -EINVAL; +} + +static inline int str_to_quirk(const char *buf, int *domain, int *bus, int + *slot, int *func, int *reg, int *size, int *mask) +{ + int parsed = 0; + + sscanf(buf, " %x:%x:%x.%x-%x:%x:%x %n", domain, bus, slot, func, + reg, size, mask, &parsed); + if (parsed && !buf[parsed]) + return 0; + + /* try again without domain */ + *domain = 0; + sscanf(buf, " %x:%x.%x-%x:%x:%x %n", bus, slot, func, reg, size, + mask, &parsed); + if (parsed && !buf[parsed]) + return 0; + + return -EINVAL; +} + +static int pcistub_device_id_add(int domain, int bus, int slot, int func) +{ + struct pcistub_device_id *pci_dev_id; + int rc = 0, devfn = PCI_DEVFN(slot, func); + + if (slot < 0) { + for (slot = 0; !rc && slot < 32; ++slot) + rc = pcistub_device_id_add(domain, bus, slot, func); + return rc; + } + + if (func < 0) { + for (func = 0; !rc && func < 8; ++func) + rc = pcistub_device_id_add(domain, bus, slot, func); + return rc; + } + + if (( +#if !defined(MODULE) /* pci_domains_supported is not being exported */ \ + || !defined(CONFIG_PCI_DOMAINS) + !pci_domains_supported ? domain : +#endif + domain < 0 || domain > 0xffff) + || bus < 0 || bus > 0xff + || PCI_SLOT(devfn) != slot + || PCI_FUNC(devfn) != func) + return -EINVAL; + + pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL); + if (!pci_dev_id) + return -ENOMEM; + + pr_debug("wants to seize %04x:%02x:%02x.%d\n", + domain, bus, slot, func); + + pcistub_device_id_add_list(pci_dev_id, domain, bus, devfn); + + return 0; +} + +static int pcistub_device_id_remove(int domain, int bus, int slot, int func) +{ + struct pcistub_device_id *pci_dev_id, *t; + int err = -ENOENT; + unsigned long flags; + + spin_lock_irqsave(&device_ids_lock, flags); + list_for_each_entry_safe(pci_dev_id, t, &pcistub_device_ids, + slot_list) { + if (pci_dev_id->domain == domain && pci_dev_id->bus == bus + && (slot < 0 || PCI_SLOT(pci_dev_id->devfn) == slot) + && (func < 0 || PCI_FUNC(pci_dev_id->devfn) == func)) { + /* Don't break; here because it's possible the same + * slot could be in the list more than once + */ + list_del(&pci_dev_id->slot_list); + kfree(pci_dev_id); + + err = 0; + + pr_debug("removed %04x:%02x:%02x.%d from seize list\n", + domain, bus, slot, func); + } + } + spin_unlock_irqrestore(&device_ids_lock, flags); + + return err; +} + +static int pcistub_reg_add(int domain, int bus, int slot, int func, + unsigned int reg, unsigned int size, + unsigned int mask) +{ + int err = 0; + struct pcistub_device *psdev; + struct pci_dev *dev; + struct config_field *field; + + if (reg > 0xfff || (size < 4 && (mask >> (size * 8)))) + return -EINVAL; + + psdev = pcistub_device_find(domain, bus, slot, func); + if (!psdev) { + err = -ENODEV; + goto out; + } + dev = psdev->dev; + + field = kzalloc(sizeof(*field), GFP_KERNEL); + if (!field) { + err = -ENOMEM; + goto out; + } + + field->offset = reg; + field->size = size; + field->mask = mask; + field->init = NULL; + field->reset = NULL; + field->release = NULL; + field->clean = xen_pcibk_config_field_free; + + err = xen_pcibk_config_quirks_add_field(dev, field); + if (err) + kfree(field); +out: + if (psdev) + pcistub_device_put(psdev); + return err; +} + +static ssize_t new_slot_store(struct device_driver *drv, const char *buf, + size_t count) +{ + int domain, bus, slot, func; + int err; + + err = str_to_slot(buf, &domain, &bus, &slot, &func); + if (err) + goto out; + + err = pcistub_device_id_add(domain, bus, slot, func); + +out: + if (!err) + err = count; + return err; +} +static DRIVER_ATTR_WO(new_slot); + +static ssize_t remove_slot_store(struct device_driver *drv, const char *buf, + size_t count) +{ + int domain, bus, slot, func; + int err; + + err = str_to_slot(buf, &domain, &bus, &slot, &func); + if (err) + goto out; + + err = pcistub_device_id_remove(domain, bus, slot, func); + +out: + if (!err) + err = count; + return err; +} +static DRIVER_ATTR_WO(remove_slot); + +static ssize_t slots_show(struct device_driver *drv, char *buf) +{ + struct pcistub_device_id *pci_dev_id; + size_t count = 0; + unsigned long flags; + + spin_lock_irqsave(&device_ids_lock, flags); + list_for_each_entry(pci_dev_id, &pcistub_device_ids, slot_list) { + if (count >= PAGE_SIZE) + break; + + count += scnprintf(buf + count, PAGE_SIZE - count, + "%04x:%02x:%02x.%d\n", + pci_dev_id->domain, pci_dev_id->bus, + PCI_SLOT(pci_dev_id->devfn), + PCI_FUNC(pci_dev_id->devfn)); + } + spin_unlock_irqrestore(&device_ids_lock, flags); + + return count; +} +static DRIVER_ATTR_RO(slots); + +static ssize_t irq_handlers_show(struct device_driver *drv, char *buf) +{ + struct pcistub_device *psdev; + struct xen_pcibk_dev_data *dev_data; + size_t count = 0; + unsigned long flags; + + spin_lock_irqsave(&pcistub_devices_lock, flags); + list_for_each_entry(psdev, &pcistub_devices, dev_list) { + if (count >= PAGE_SIZE) + break; + if (!psdev->dev) + continue; + dev_data = pci_get_drvdata(psdev->dev); + if (!dev_data) + continue; + count += + scnprintf(buf + count, PAGE_SIZE - count, + "%s:%s:%sing:%ld\n", + pci_name(psdev->dev), + dev_data->isr_on ? "on" : "off", + dev_data->ack_intr ? "ack" : "not ack", + dev_data->handled); + } + spin_unlock_irqrestore(&pcistub_devices_lock, flags); + return count; +} +static DRIVER_ATTR_RO(irq_handlers); + +static ssize_t irq_handler_state_store(struct device_driver *drv, + const char *buf, size_t count) +{ + struct pcistub_device *psdev; + struct xen_pcibk_dev_data *dev_data; + int domain, bus, slot, func; + int err; + + err = str_to_slot(buf, &domain, &bus, &slot, &func); + if (err) + return err; + + psdev = pcistub_device_find(domain, bus, slot, func); + if (!psdev) { + err = -ENOENT; + goto out; + } + + dev_data = pci_get_drvdata(psdev->dev); + if (!dev_data) { + err = -ENOENT; + goto out; + } + + dev_dbg(&psdev->dev->dev, "%s fake irq handler: %d->%d\n", + dev_data->irq_name, dev_data->isr_on, + !dev_data->isr_on); + + dev_data->isr_on = !(dev_data->isr_on); + if (dev_data->isr_on) + dev_data->ack_intr = 1; +out: + if (psdev) + pcistub_device_put(psdev); + if (!err) + err = count; + return err; +} +static DRIVER_ATTR_WO(irq_handler_state); + +static ssize_t quirks_store(struct device_driver *drv, const char *buf, + size_t count) +{ + int domain, bus, slot, func, reg, size, mask; + int err; + + err = str_to_quirk(buf, &domain, &bus, &slot, &func, ®, &size, + &mask); + if (err) + goto out; + + err = pcistub_reg_add(domain, bus, slot, func, reg, size, mask); + +out: + if (!err) + err = count; + return err; +} + +static ssize_t quirks_show(struct device_driver *drv, char *buf) +{ + int count = 0; + unsigned long flags; + struct xen_pcibk_config_quirk *quirk; + struct xen_pcibk_dev_data *dev_data; + const struct config_field *field; + const struct config_field_entry *cfg_entry; + + spin_lock_irqsave(&device_ids_lock, flags); + list_for_each_entry(quirk, &xen_pcibk_quirks, quirks_list) { + if (count >= PAGE_SIZE) + goto out; + + count += scnprintf(buf + count, PAGE_SIZE - count, + "%02x:%02x.%01x\n\t%04x:%04x:%04x:%04x\n", + quirk->pdev->bus->number, + PCI_SLOT(quirk->pdev->devfn), + PCI_FUNC(quirk->pdev->devfn), + quirk->devid.vendor, quirk->devid.device, + quirk->devid.subvendor, + quirk->devid.subdevice); + + dev_data = pci_get_drvdata(quirk->pdev); + + list_for_each_entry(cfg_entry, &dev_data->config_fields, list) { + field = cfg_entry->field; + if (count >= PAGE_SIZE) + goto out; + + count += scnprintf(buf + count, PAGE_SIZE - count, + "\t\t%08x:%01x:%08x\n", + cfg_entry->base_offset + + field->offset, field->size, + field->mask); + } + } + +out: + spin_unlock_irqrestore(&device_ids_lock, flags); + + return count; +} +static DRIVER_ATTR_RW(quirks); + +static ssize_t permissive_store(struct device_driver *drv, const char *buf, + size_t count) +{ + int domain, bus, slot, func; + int err; + struct pcistub_device *psdev; + struct xen_pcibk_dev_data *dev_data; + + err = str_to_slot(buf, &domain, &bus, &slot, &func); + if (err) + goto out; + + psdev = pcistub_device_find(domain, bus, slot, func); + if (!psdev) { + err = -ENODEV; + goto out; + } + + dev_data = pci_get_drvdata(psdev->dev); + /* the driver data for a device should never be null at this point */ + if (!dev_data) { + err = -ENXIO; + goto release; + } + if (!dev_data->permissive) { + dev_data->permissive = 1; + /* Let user know that what they're doing could be unsafe */ + dev_warn(&psdev->dev->dev, "enabling permissive mode " + "configuration space accesses!\n"); + dev_warn(&psdev->dev->dev, + "permissive mode is potentially unsafe!\n"); + } +release: + pcistub_device_put(psdev); +out: + if (!err) + err = count; + return err; +} + +static ssize_t permissive_show(struct device_driver *drv, char *buf) +{ + struct pcistub_device *psdev; + struct xen_pcibk_dev_data *dev_data; + size_t count = 0; + unsigned long flags; + spin_lock_irqsave(&pcistub_devices_lock, flags); + list_for_each_entry(psdev, &pcistub_devices, dev_list) { + if (count >= PAGE_SIZE) + break; + if (!psdev->dev) + continue; + dev_data = pci_get_drvdata(psdev->dev); + if (!dev_data || !dev_data->permissive) + continue; + count += + scnprintf(buf + count, PAGE_SIZE - count, "%s\n", + pci_name(psdev->dev)); + } + spin_unlock_irqrestore(&pcistub_devices_lock, flags); + return count; +} +static DRIVER_ATTR_RW(permissive); + +static void pcistub_exit(void) +{ + driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_new_slot); + driver_remove_file(&xen_pcibk_pci_driver.driver, + &driver_attr_remove_slot); + driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_slots); + driver_remove_file(&xen_pcibk_pci_driver.driver, &driver_attr_quirks); + driver_remove_file(&xen_pcibk_pci_driver.driver, + &driver_attr_permissive); + driver_remove_file(&xen_pcibk_pci_driver.driver, + &driver_attr_irq_handlers); + driver_remove_file(&xen_pcibk_pci_driver.driver, + &driver_attr_irq_handler_state); + pci_unregister_driver(&xen_pcibk_pci_driver); +} + +static int __init pcistub_init(void) +{ + int pos = 0; + int err = 0; + int domain, bus, slot, func; + int parsed; + + if (pci_devs_to_hide && *pci_devs_to_hide) { + do { + parsed = 0; + + err = sscanf(pci_devs_to_hide + pos, + " (%x:%x:%x.%x) %n", + &domain, &bus, &slot, &func, &parsed); + switch (err) { + case 3: + func = -1; + sscanf(pci_devs_to_hide + pos, + " (%x:%x:%x.*) %n", + &domain, &bus, &slot, &parsed); + break; + case 2: + slot = func = -1; + sscanf(pci_devs_to_hide + pos, + " (%x:%x:*.*) %n", + &domain, &bus, &parsed); + break; + } + + if (!parsed) { + domain = 0; + err = sscanf(pci_devs_to_hide + pos, + " (%x:%x.%x) %n", + &bus, &slot, &func, &parsed); + switch (err) { + case 2: + func = -1; + sscanf(pci_devs_to_hide + pos, + " (%x:%x.*) %n", + &bus, &slot, &parsed); + break; + case 1: + slot = func = -1; + sscanf(pci_devs_to_hide + pos, + " (%x:*.*) %n", + &bus, &parsed); + break; + } + } + + if (parsed <= 0) + goto parse_error; + + err = pcistub_device_id_add(domain, bus, slot, func); + if (err) + goto out; + + pos += parsed; + } while (pci_devs_to_hide[pos]); + } + + /* If we're the first PCI Device Driver to register, we're the + * first one to get offered PCI devices as they become + * available (and thus we can be the first to grab them) + */ + err = pci_register_driver(&xen_pcibk_pci_driver); + if (err < 0) + goto out; + + err = driver_create_file(&xen_pcibk_pci_driver.driver, + &driver_attr_new_slot); + if (!err) + err = driver_create_file(&xen_pcibk_pci_driver.driver, + &driver_attr_remove_slot); + if (!err) + err = driver_create_file(&xen_pcibk_pci_driver.driver, + &driver_attr_slots); + if (!err) + err = driver_create_file(&xen_pcibk_pci_driver.driver, + &driver_attr_quirks); + if (!err) + err = driver_create_file(&xen_pcibk_pci_driver.driver, + &driver_attr_permissive); + + if (!err) + err = driver_create_file(&xen_pcibk_pci_driver.driver, + &driver_attr_irq_handlers); + if (!err) + err = driver_create_file(&xen_pcibk_pci_driver.driver, + &driver_attr_irq_handler_state); + if (err) + pcistub_exit(); + +out: + return err; + +parse_error: + pr_err("Error parsing pci_devs_to_hide at \"%s\"\n", + pci_devs_to_hide + pos); + return -EINVAL; +} + +#ifndef MODULE +/* + * fs_initcall happens before device_initcall + * so xen_pcibk *should* get called first (b/c we + * want to suck up any device before other drivers + * get a chance by being the first pci device + * driver to register) + */ +fs_initcall(pcistub_init); +#endif + +#ifdef CONFIG_PCI_IOV +static struct pcistub_device *find_vfs(const struct pci_dev *pdev) +{ + struct pcistub_device *psdev = NULL; + unsigned long flags; + bool found = false; + + spin_lock_irqsave(&pcistub_devices_lock, flags); + list_for_each_entry(psdev, &pcistub_devices, dev_list) { + if (!psdev->pdev && psdev->dev != pdev + && pci_physfn(psdev->dev) == pdev) { + found = true; + break; + } + } + spin_unlock_irqrestore(&pcistub_devices_lock, flags); + if (found) + return psdev; + return NULL; +} + +static int pci_stub_notifier(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct device *dev = data; + const struct pci_dev *pdev = to_pci_dev(dev); + + if (action != BUS_NOTIFY_UNBIND_DRIVER) + return NOTIFY_DONE; + + if (!pdev->is_physfn) + return NOTIFY_DONE; + + for (;;) { + struct pcistub_device *psdev = find_vfs(pdev); + if (!psdev) + break; + device_release_driver(&psdev->dev->dev); + } + return NOTIFY_DONE; +} + +static struct notifier_block pci_stub_nb = { + .notifier_call = pci_stub_notifier, +}; +#endif + +static int __init xen_pcibk_init(void) +{ + int err; + + if (!xen_initial_domain()) + return -ENODEV; + + err = xen_pcibk_config_init(); + if (err) + return err; + +#ifdef MODULE + err = pcistub_init(); + if (err < 0) + return err; +#endif + + pcistub_init_devices_late(); + err = xen_pcibk_xenbus_register(); + if (err) + pcistub_exit(); +#ifdef CONFIG_PCI_IOV + else + bus_register_notifier(&pci_bus_type, &pci_stub_nb); +#endif + + return err; +} + +static void __exit xen_pcibk_cleanup(void) +{ +#ifdef CONFIG_PCI_IOV + bus_unregister_notifier(&pci_bus_type, &pci_stub_nb); +#endif + xen_pcibk_xenbus_unregister(); + pcistub_exit(); +} + +module_init(xen_pcibk_init); +module_exit(xen_pcibk_cleanup); + +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_ALIAS("xen-backend:pci"); |