| /* |
| * Xen PCI Frontend. |
| * |
| * Author: Ryan Wilson <hap9@epoch.ncsc.mil> |
| */ |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/mm.h> |
| #include <xen/xenbus.h> |
| #include <xen/events.h> |
| #include <xen/grant_table.h> |
| #include <xen/page.h> |
| #include <linux/spinlock.h> |
| #include <linux/pci.h> |
| #include <linux/msi.h> |
| #include <xen/interface/io/pciif.h> |
| #include <asm/xen/pci.h> |
| #include <linux/interrupt.h> |
| #include <linux/atomic.h> |
| #include <linux/workqueue.h> |
| #include <linux/bitops.h> |
| #include <linux/time.h> |
| |
| #include <asm/xen/swiotlb-xen.h> |
| #define INVALID_GRANT_REF (0) |
| #define INVALID_EVTCHN (-1) |
| |
| struct pci_bus_entry { |
| struct list_head list; |
| struct pci_bus *bus; |
| }; |
| |
| #define _PDEVB_op_active (0) |
| #define PDEVB_op_active (1 << (_PDEVB_op_active)) |
| |
| struct pcifront_device { |
| struct xenbus_device *xdev; |
| struct list_head root_buses; |
| |
| int evtchn; |
| int gnt_ref; |
| |
| int irq; |
| |
| /* Lock this when doing any operations in sh_info */ |
| spinlock_t sh_info_lock; |
| struct xen_pci_sharedinfo *sh_info; |
| struct work_struct op_work; |
| unsigned long flags; |
| |
| }; |
| |
| struct pcifront_sd { |
| int domain; |
| struct pcifront_device *pdev; |
| }; |
| |
| static inline struct pcifront_device * |
| pcifront_get_pdev(struct pcifront_sd *sd) |
| { |
| return sd->pdev; |
| } |
| |
| static inline void pcifront_init_sd(struct pcifront_sd *sd, |
| unsigned int domain, unsigned int bus, |
| struct pcifront_device *pdev) |
| { |
| sd->domain = domain; |
| sd->pdev = pdev; |
| } |
| |
| static DEFINE_SPINLOCK(pcifront_dev_lock); |
| static struct pcifront_device *pcifront_dev; |
| |
| static int verbose_request; |
| module_param(verbose_request, int, 0644); |
| |
| static int errno_to_pcibios_err(int errno) |
| { |
| switch (errno) { |
| case XEN_PCI_ERR_success: |
| return PCIBIOS_SUCCESSFUL; |
| |
| case XEN_PCI_ERR_dev_not_found: |
| return PCIBIOS_DEVICE_NOT_FOUND; |
| |
| case XEN_PCI_ERR_invalid_offset: |
| case XEN_PCI_ERR_op_failed: |
| return PCIBIOS_BAD_REGISTER_NUMBER; |
| |
| case XEN_PCI_ERR_not_implemented: |
| return PCIBIOS_FUNC_NOT_SUPPORTED; |
| |
| case XEN_PCI_ERR_access_denied: |
| return PCIBIOS_SET_FAILED; |
| } |
| return errno; |
| } |
| |
| static inline void schedule_pcifront_aer_op(struct pcifront_device *pdev) |
| { |
| if (test_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags) |
| && !test_and_set_bit(_PDEVB_op_active, &pdev->flags)) { |
| dev_dbg(&pdev->xdev->dev, "schedule aer frontend job\n"); |
| schedule_work(&pdev->op_work); |
| } |
| } |
| |
| static int do_pci_op(struct pcifront_device *pdev, struct xen_pci_op *op) |
| { |
| int err = 0; |
| struct xen_pci_op *active_op = &pdev->sh_info->op; |
| unsigned long irq_flags; |
| evtchn_port_t port = pdev->evtchn; |
| unsigned irq = pdev->irq; |
| s64 ns, ns_timeout; |
| struct timeval tv; |
| |
| spin_lock_irqsave(&pdev->sh_info_lock, irq_flags); |
| |
| memcpy(active_op, op, sizeof(struct xen_pci_op)); |
| |
| /* Go */ |
| wmb(); |
| set_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags); |
| notify_remote_via_evtchn(port); |
| |
| /* |
| * We set a poll timeout of 3 seconds but give up on return after |
| * 2 seconds. It is better to time out too late rather than too early |
| * (in the latter case we end up continually re-executing poll() with a |
| * timeout in the past). 1s difference gives plenty of slack for error. |
| */ |
| do_gettimeofday(&tv); |
| ns_timeout = timeval_to_ns(&tv) + 2 * (s64)NSEC_PER_SEC; |
| |
| xen_clear_irq_pending(irq); |
| |
| while (test_bit(_XEN_PCIF_active, |
| (unsigned long *)&pdev->sh_info->flags)) { |
| xen_poll_irq_timeout(irq, jiffies + 3*HZ); |
| xen_clear_irq_pending(irq); |
| do_gettimeofday(&tv); |
| ns = timeval_to_ns(&tv); |
| if (ns > ns_timeout) { |
| dev_err(&pdev->xdev->dev, |
| "pciback not responding!!!\n"); |
| clear_bit(_XEN_PCIF_active, |
| (unsigned long *)&pdev->sh_info->flags); |
| err = XEN_PCI_ERR_dev_not_found; |
| goto out; |
| } |
| } |
| |
| /* |
| * We might lose backend service request since we |
| * reuse same evtchn with pci_conf backend response. So re-schedule |
| * aer pcifront service. |
| */ |
| if (test_bit(_XEN_PCIB_active, |
| (unsigned long *)&pdev->sh_info->flags)) { |
| dev_err(&pdev->xdev->dev, |
| "schedule aer pcifront service\n"); |
| schedule_pcifront_aer_op(pdev); |
| } |
| |
| memcpy(op, active_op, sizeof(struct xen_pci_op)); |
| |
| err = op->err; |
| out: |
| spin_unlock_irqrestore(&pdev->sh_info_lock, irq_flags); |
| return err; |
| } |
| |
| /* Access to this function is spinlocked in drivers/pci/access.c */ |
| static int pcifront_bus_read(struct pci_bus *bus, unsigned int devfn, |
| int where, int size, u32 *val) |
| { |
| int err = 0; |
| struct xen_pci_op op = { |
| .cmd = XEN_PCI_OP_conf_read, |
| .domain = pci_domain_nr(bus), |
| .bus = bus->number, |
| .devfn = devfn, |
| .offset = where, |
| .size = size, |
| }; |
| struct pcifront_sd *sd = bus->sysdata; |
| struct pcifront_device *pdev = pcifront_get_pdev(sd); |
| |
| if (verbose_request) |
| dev_info(&pdev->xdev->dev, |
| "read dev=%04x:%02x:%02x.%d - offset %x size %d\n", |
| pci_domain_nr(bus), bus->number, PCI_SLOT(devfn), |
| PCI_FUNC(devfn), where, size); |
| |
| err = do_pci_op(pdev, &op); |
| |
| if (likely(!err)) { |
| if (verbose_request) |
| dev_info(&pdev->xdev->dev, "read got back value %x\n", |
| op.value); |
| |
| *val = op.value; |
| } else if (err == -ENODEV) { |
| /* No device here, pretend that it just returned 0 */ |
| err = 0; |
| *val = 0; |
| } |
| |
| return errno_to_pcibios_err(err); |
| } |
| |
| /* Access to this function is spinlocked in drivers/pci/access.c */ |
| static int pcifront_bus_write(struct pci_bus *bus, unsigned int devfn, |
| int where, int size, u32 val) |
| { |
| struct xen_pci_op op = { |
| .cmd = XEN_PCI_OP_conf_write, |
| .domain = pci_domain_nr(bus), |
| .bus = bus->number, |
| .devfn = devfn, |
| .offset = where, |
| .size = size, |
| .value = val, |
| }; |
| struct pcifront_sd *sd = bus->sysdata; |
| struct pcifront_device *pdev = pcifront_get_pdev(sd); |
| |
| if (verbose_request) |
| dev_info(&pdev->xdev->dev, |
| "write dev=%04x:%02x:%02x.%d - " |
| "offset %x size %d val %x\n", |
| pci_domain_nr(bus), bus->number, |
| PCI_SLOT(devfn), PCI_FUNC(devfn), where, size, val); |
| |
| return errno_to_pcibios_err(do_pci_op(pdev, &op)); |
| } |
| |
| static struct pci_ops pcifront_bus_ops = { |
| .read = pcifront_bus_read, |
| .write = pcifront_bus_write, |
| }; |
| |
| #ifdef CONFIG_PCI_MSI |
| static int pci_frontend_enable_msix(struct pci_dev *dev, |
| int vector[], int nvec) |
| { |
| int err; |
| int i; |
| struct xen_pci_op op = { |
| .cmd = XEN_PCI_OP_enable_msix, |
| .domain = pci_domain_nr(dev->bus), |
| .bus = dev->bus->number, |
| .devfn = dev->devfn, |
| .value = nvec, |
| }; |
| struct pcifront_sd *sd = dev->bus->sysdata; |
| struct pcifront_device *pdev = pcifront_get_pdev(sd); |
| struct msi_desc *entry; |
| |
| if (nvec > SH_INFO_MAX_VEC) { |
| dev_err(&dev->dev, "too much vector for pci frontend: %x." |
| " Increase SH_INFO_MAX_VEC.\n", nvec); |
| return -EINVAL; |
| } |
| |
| i = 0; |
| list_for_each_entry(entry, &dev->msi_list, list) { |
| op.msix_entries[i].entry = entry->msi_attrib.entry_nr; |
| /* Vector is useless at this point. */ |
| op.msix_entries[i].vector = -1; |
| i++; |
| } |
| |
| err = do_pci_op(pdev, &op); |
| |
| if (likely(!err)) { |
| if (likely(!op.value)) { |
| /* we get the result */ |
| for (i = 0; i < nvec; i++) { |
| if (op.msix_entries[i].vector <= 0) { |
| dev_warn(&dev->dev, "MSI-X entry %d is invalid: %d!\n", |
| i, op.msix_entries[i].vector); |
| err = -EINVAL; |
| vector[i] = -1; |
| continue; |
| } |
| vector[i] = op.msix_entries[i].vector; |
| } |
| } else { |
| printk(KERN_DEBUG "enable msix get value %x\n", |
| op.value); |
| err = op.value; |
| } |
| } else { |
| dev_err(&dev->dev, "enable msix get err %x\n", err); |
| } |
| return err; |
| } |
| |
| static void pci_frontend_disable_msix(struct pci_dev *dev) |
| { |
| int err; |
| struct xen_pci_op op = { |
| .cmd = XEN_PCI_OP_disable_msix, |
| .domain = pci_domain_nr(dev->bus), |
| .bus = dev->bus->number, |
| .devfn = dev->devfn, |
| }; |
| struct pcifront_sd *sd = dev->bus->sysdata; |
| struct pcifront_device *pdev = pcifront_get_pdev(sd); |
| |
| err = do_pci_op(pdev, &op); |
| |
| /* What should do for error ? */ |
| if (err) |
| dev_err(&dev->dev, "pci_disable_msix get err %x\n", err); |
| } |
| |
| static int pci_frontend_enable_msi(struct pci_dev *dev, int vector[]) |
| { |
| int err; |
| struct xen_pci_op op = { |
| .cmd = XEN_PCI_OP_enable_msi, |
| .domain = pci_domain_nr(dev->bus), |
| .bus = dev->bus->number, |
| .devfn = dev->devfn, |
| }; |
| struct pcifront_sd *sd = dev->bus->sysdata; |
| struct pcifront_device *pdev = pcifront_get_pdev(sd); |
| |
| err = do_pci_op(pdev, &op); |
| if (likely(!err)) { |
| vector[0] = op.value; |
| if (op.value <= 0) { |
| dev_warn(&dev->dev, "MSI entry is invalid: %d!\n", |
| op.value); |
| err = -EINVAL; |
| vector[0] = -1; |
| } |
| } else { |
| dev_err(&dev->dev, "pci frontend enable msi failed for dev " |
| "%x:%x\n", op.bus, op.devfn); |
| err = -EINVAL; |
| } |
| return err; |
| } |
| |
| static void pci_frontend_disable_msi(struct pci_dev *dev) |
| { |
| int err; |
| struct xen_pci_op op = { |
| .cmd = XEN_PCI_OP_disable_msi, |
| .domain = pci_domain_nr(dev->bus), |
| .bus = dev->bus->number, |
| .devfn = dev->devfn, |
| }; |
| struct pcifront_sd *sd = dev->bus->sysdata; |
| struct pcifront_device *pdev = pcifront_get_pdev(sd); |
| |
| err = do_pci_op(pdev, &op); |
| if (err == XEN_PCI_ERR_dev_not_found) { |
| /* XXX No response from backend, what shall we do? */ |
| printk(KERN_DEBUG "get no response from backend for disable MSI\n"); |
| return; |
| } |
| if (err) |
| /* how can pciback notify us fail? */ |
| printk(KERN_DEBUG "get fake response frombackend\n"); |
| } |
| |
| static struct xen_pci_frontend_ops pci_frontend_ops = { |
| .enable_msi = pci_frontend_enable_msi, |
| .disable_msi = pci_frontend_disable_msi, |
| .enable_msix = pci_frontend_enable_msix, |
| .disable_msix = pci_frontend_disable_msix, |
| }; |
| |
| static void pci_frontend_registrar(int enable) |
| { |
| if (enable) |
| xen_pci_frontend = &pci_frontend_ops; |
| else |
| xen_pci_frontend = NULL; |
| }; |
| #else |
| static inline void pci_frontend_registrar(int enable) { }; |
| #endif /* CONFIG_PCI_MSI */ |
| |
| /* Claim resources for the PCI frontend as-is, backend won't allow changes */ |
| static int pcifront_claim_resource(struct pci_dev *dev, void *data) |
| { |
| struct pcifront_device *pdev = data; |
| int i; |
| struct resource *r; |
| |
| for (i = 0; i < PCI_NUM_RESOURCES; i++) { |
| r = &dev->resource[i]; |
| |
| if (!r->parent && r->start && r->flags) { |
| dev_info(&pdev->xdev->dev, "claiming resource %s/%d\n", |
| pci_name(dev), i); |
| if (pci_claim_resource(dev, i)) { |
| dev_err(&pdev->xdev->dev, "Could not claim resource %s/%d! " |
| "Device offline. Try using e820_host=1 in the guest config.\n", |
| pci_name(dev), i); |
| } |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int pcifront_scan_bus(struct pcifront_device *pdev, |
| unsigned int domain, unsigned int bus, |
| struct pci_bus *b) |
| { |
| struct pci_dev *d; |
| unsigned int devfn; |
| |
| /* Scan the bus for functions and add. |
| * We omit handling of PCI bridge attachment because pciback prevents |
| * bridges from being exported. |
| */ |
| for (devfn = 0; devfn < 0x100; devfn++) { |
| d = pci_get_slot(b, devfn); |
| if (d) { |
| /* Device is already known. */ |
| pci_dev_put(d); |
| continue; |
| } |
| |
| d = pci_scan_single_device(b, devfn); |
| if (d) |
| dev_info(&pdev->xdev->dev, "New device on " |
| "%04x:%02x:%02x.%d found.\n", domain, bus, |
| PCI_SLOT(devfn), PCI_FUNC(devfn)); |
| } |
| |
| return 0; |
| } |
| |
| static int pcifront_scan_root(struct pcifront_device *pdev, |
| unsigned int domain, unsigned int bus) |
| { |
| struct pci_bus *b; |
| struct pcifront_sd *sd = NULL; |
| struct pci_bus_entry *bus_entry = NULL; |
| int err = 0; |
| |
| #ifndef CONFIG_PCI_DOMAINS |
| if (domain != 0) { |
| dev_err(&pdev->xdev->dev, |
| "PCI Root in non-zero PCI Domain! domain=%d\n", domain); |
| dev_err(&pdev->xdev->dev, |
| "Please compile with CONFIG_PCI_DOMAINS\n"); |
| err = -EINVAL; |
| goto err_out; |
| } |
| #endif |
| |
| dev_info(&pdev->xdev->dev, "Creating PCI Frontend Bus %04x:%02x\n", |
| domain, bus); |
| |
| bus_entry = kmalloc(sizeof(*bus_entry), GFP_KERNEL); |
| sd = kmalloc(sizeof(*sd), GFP_KERNEL); |
| if (!bus_entry || !sd) { |
| err = -ENOMEM; |
| goto err_out; |
| } |
| pcifront_init_sd(sd, domain, bus, pdev); |
| |
| pci_lock_rescan_remove(); |
| |
| b = pci_scan_bus_parented(&pdev->xdev->dev, bus, |
| &pcifront_bus_ops, sd); |
| if (!b) { |
| dev_err(&pdev->xdev->dev, |
| "Error creating PCI Frontend Bus!\n"); |
| err = -ENOMEM; |
| pci_unlock_rescan_remove(); |
| goto err_out; |
| } |
| |
| bus_entry->bus = b; |
| |
| list_add(&bus_entry->list, &pdev->root_buses); |
| |
| /* pci_scan_bus_parented skips devices which do not have a have |
| * devfn==0. The pcifront_scan_bus enumerates all devfn. */ |
| err = pcifront_scan_bus(pdev, domain, bus, b); |
| |
| /* Claim resources before going "live" with our devices */ |
| pci_walk_bus(b, pcifront_claim_resource, pdev); |
| |
| /* Create SysFS and notify udev of the devices. Aka: "going live" */ |
| pci_bus_add_devices(b); |
| |
| pci_unlock_rescan_remove(); |
| return err; |
| |
| err_out: |
| kfree(bus_entry); |
| kfree(sd); |
| |
| return err; |
| } |
| |
| static int pcifront_rescan_root(struct pcifront_device *pdev, |
| unsigned int domain, unsigned int bus) |
| { |
| int err; |
| struct pci_bus *b; |
| |
| #ifndef CONFIG_PCI_DOMAINS |
| if (domain != 0) { |
| dev_err(&pdev->xdev->dev, |
| "PCI Root in non-zero PCI Domain! domain=%d\n", domain); |
| dev_err(&pdev->xdev->dev, |
| "Please compile with CONFIG_PCI_DOMAINS\n"); |
| return -EINVAL; |
| } |
| #endif |
| |
| dev_info(&pdev->xdev->dev, "Rescanning PCI Frontend Bus %04x:%02x\n", |
| domain, bus); |
| |
| b = pci_find_bus(domain, bus); |
| if (!b) |
| /* If the bus is unknown, create it. */ |
| return pcifront_scan_root(pdev, domain, bus); |
| |
| err = pcifront_scan_bus(pdev, domain, bus, b); |
| |
| /* Claim resources before going "live" with our devices */ |
| pci_walk_bus(b, pcifront_claim_resource, pdev); |
| |
| /* Create SysFS and notify udev of the devices. Aka: "going live" */ |
| pci_bus_add_devices(b); |
| |
| return err; |
| } |
| |
| static void free_root_bus_devs(struct pci_bus *bus) |
| { |
| struct pci_dev *dev; |
| |
| while (!list_empty(&bus->devices)) { |
| dev = container_of(bus->devices.next, struct pci_dev, |
| bus_list); |
| dev_dbg(&dev->dev, "removing device\n"); |
| pci_stop_and_remove_bus_device(dev); |
| } |
| } |
| |
| static void pcifront_free_roots(struct pcifront_device *pdev) |
| { |
| struct pci_bus_entry *bus_entry, *t; |
| |
| dev_dbg(&pdev->xdev->dev, "cleaning up root buses\n"); |
| |
| pci_lock_rescan_remove(); |
| list_for_each_entry_safe(bus_entry, t, &pdev->root_buses, list) { |
| list_del(&bus_entry->list); |
| |
| free_root_bus_devs(bus_entry->bus); |
| |
| kfree(bus_entry->bus->sysdata); |
| |
| device_unregister(bus_entry->bus->bridge); |
| pci_remove_bus(bus_entry->bus); |
| |
| kfree(bus_entry); |
| } |
| pci_unlock_rescan_remove(); |
| } |
| |
| static pci_ers_result_t pcifront_common_process(int cmd, |
| struct pcifront_device *pdev, |
| pci_channel_state_t state) |
| { |
| pci_ers_result_t result; |
| struct pci_driver *pdrv; |
| int bus = pdev->sh_info->aer_op.bus; |
| int devfn = pdev->sh_info->aer_op.devfn; |
| struct pci_dev *pcidev; |
| int flag = 0; |
| |
| dev_dbg(&pdev->xdev->dev, |
| "pcifront AER process: cmd %x (bus:%x, devfn%x)", |
| cmd, bus, devfn); |
| result = PCI_ERS_RESULT_NONE; |
| |
| pcidev = pci_get_bus_and_slot(bus, devfn); |
| if (!pcidev || !pcidev->driver) { |
| dev_err(&pdev->xdev->dev, "device or AER driver is NULL\n"); |
| if (pcidev) |
| pci_dev_put(pcidev); |
| return result; |
| } |
| pdrv = pcidev->driver; |
| |
| if (pdrv) { |
| if (pdrv->err_handler && pdrv->err_handler->error_detected) { |
| dev_dbg(&pcidev->dev, |
| "trying to call AER service\n"); |
| if (pcidev) { |
| flag = 1; |
| switch (cmd) { |
| case XEN_PCI_OP_aer_detected: |
| result = pdrv->err_handler-> |
| error_detected(pcidev, state); |
| break; |
| case XEN_PCI_OP_aer_mmio: |
| result = pdrv->err_handler-> |
| mmio_enabled(pcidev); |
| break; |
| case XEN_PCI_OP_aer_slotreset: |
| result = pdrv->err_handler-> |
| slot_reset(pcidev); |
| break; |
| case XEN_PCI_OP_aer_resume: |
| pdrv->err_handler->resume(pcidev); |
| break; |
| default: |
| dev_err(&pdev->xdev->dev, |
| "bad request in aer recovery " |
| "operation!\n"); |
| |
| } |
| } |
| } |
| } |
| if (!flag) |
| result = PCI_ERS_RESULT_NONE; |
| |
| return result; |
| } |
| |
| |
| static void pcifront_do_aer(struct work_struct *data) |
| { |
| struct pcifront_device *pdev = |
| container_of(data, struct pcifront_device, op_work); |
| int cmd = pdev->sh_info->aer_op.cmd; |
| pci_channel_state_t state = |
| (pci_channel_state_t)pdev->sh_info->aer_op.err; |
| |
| /*If a pci_conf op is in progress, |
| we have to wait until it is done before service aer op*/ |
| dev_dbg(&pdev->xdev->dev, |
| "pcifront service aer bus %x devfn %x\n", |
| pdev->sh_info->aer_op.bus, pdev->sh_info->aer_op.devfn); |
| |
| pdev->sh_info->aer_op.err = pcifront_common_process(cmd, pdev, state); |
| |
| /* Post the operation to the guest. */ |
| wmb(); |
| clear_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags); |
| notify_remote_via_evtchn(pdev->evtchn); |
| |
| /*in case of we lost an aer request in four lines time_window*/ |
| smp_mb__before_clear_bit(); |
| clear_bit(_PDEVB_op_active, &pdev->flags); |
| smp_mb__after_clear_bit(); |
| |
| schedule_pcifront_aer_op(pdev); |
| |
| } |
| |
| static irqreturn_t pcifront_handler_aer(int irq, void *dev) |
| { |
| struct pcifront_device *pdev = dev; |
| schedule_pcifront_aer_op(pdev); |
| return IRQ_HANDLED; |
| } |
| static int pcifront_connect_and_init_dma(struct pcifront_device *pdev) |
| { |
| int err = 0; |
| |
| spin_lock(&pcifront_dev_lock); |
| |
| if (!pcifront_dev) { |
| dev_info(&pdev->xdev->dev, "Installing PCI frontend\n"); |
| pcifront_dev = pdev; |
| } else |
| err = -EEXIST; |
| |
| spin_unlock(&pcifront_dev_lock); |
| |
| if (!err && !swiotlb_nr_tbl()) { |
| err = pci_xen_swiotlb_init_late(); |
| if (err) |
| dev_err(&pdev->xdev->dev, "Could not setup SWIOTLB!\n"); |
| } |
| return err; |
| } |
| |
| static void pcifront_disconnect(struct pcifront_device *pdev) |
| { |
| spin_lock(&pcifront_dev_lock); |
| |
| if (pdev == pcifront_dev) { |
| dev_info(&pdev->xdev->dev, |
| "Disconnecting PCI Frontend Buses\n"); |
| pcifront_dev = NULL; |
| } |
| |
| spin_unlock(&pcifront_dev_lock); |
| } |
| static struct pcifront_device *alloc_pdev(struct xenbus_device *xdev) |
| { |
| struct pcifront_device *pdev; |
| |
| pdev = kzalloc(sizeof(struct pcifront_device), GFP_KERNEL); |
| if (pdev == NULL) |
| goto out; |
| |
| pdev->sh_info = |
| (struct xen_pci_sharedinfo *)__get_free_page(GFP_KERNEL); |
| if (pdev->sh_info == NULL) { |
| kfree(pdev); |
| pdev = NULL; |
| goto out; |
| } |
| pdev->sh_info->flags = 0; |
| |
| /*Flag for registering PV AER handler*/ |
| set_bit(_XEN_PCIB_AERHANDLER, (void *)&pdev->sh_info->flags); |
| |
| dev_set_drvdata(&xdev->dev, pdev); |
| pdev->xdev = xdev; |
| |
| INIT_LIST_HEAD(&pdev->root_buses); |
| |
| spin_lock_init(&pdev->sh_info_lock); |
| |
| pdev->evtchn = INVALID_EVTCHN; |
| pdev->gnt_ref = INVALID_GRANT_REF; |
| pdev->irq = -1; |
| |
| INIT_WORK(&pdev->op_work, pcifront_do_aer); |
| |
| dev_dbg(&xdev->dev, "Allocated pdev @ 0x%p pdev->sh_info @ 0x%p\n", |
| pdev, pdev->sh_info); |
| out: |
| return pdev; |
| } |
| |
| static void free_pdev(struct pcifront_device *pdev) |
| { |
| dev_dbg(&pdev->xdev->dev, "freeing pdev @ 0x%p\n", pdev); |
| |
| pcifront_free_roots(pdev); |
| |
| cancel_work_sync(&pdev->op_work); |
| |
| if (pdev->irq >= 0) |
| unbind_from_irqhandler(pdev->irq, pdev); |
| |
| if (pdev->evtchn != INVALID_EVTCHN) |
| xenbus_free_evtchn(pdev->xdev, pdev->evtchn); |
| |
| if (pdev->gnt_ref != INVALID_GRANT_REF) |
| gnttab_end_foreign_access(pdev->gnt_ref, 0 /* r/w page */, |
| (unsigned long)pdev->sh_info); |
| else |
| free_page((unsigned long)pdev->sh_info); |
| |
| dev_set_drvdata(&pdev->xdev->dev, NULL); |
| |
| kfree(pdev); |
| } |
| |
| static int pcifront_publish_info(struct pcifront_device *pdev) |
| { |
| int err = 0; |
| struct xenbus_transaction trans; |
| |
| err = xenbus_grant_ring(pdev->xdev, virt_to_mfn(pdev->sh_info)); |
| if (err < 0) |
| goto out; |
| |
| pdev->gnt_ref = err; |
| |
| err = xenbus_alloc_evtchn(pdev->xdev, &pdev->evtchn); |
| if (err) |
| goto out; |
| |
| err = bind_evtchn_to_irqhandler(pdev->evtchn, pcifront_handler_aer, |
| 0, "pcifront", pdev); |
| |
| if (err < 0) |
| return err; |
| |
| pdev->irq = err; |
| |
| do_publish: |
| err = xenbus_transaction_start(&trans); |
| if (err) { |
| xenbus_dev_fatal(pdev->xdev, err, |
| "Error writing configuration for backend " |
| "(start transaction)"); |
| goto out; |
| } |
| |
| err = xenbus_printf(trans, pdev->xdev->nodename, |
| "pci-op-ref", "%u", pdev->gnt_ref); |
| if (!err) |
| err = xenbus_printf(trans, pdev->xdev->nodename, |
| "event-channel", "%u", pdev->evtchn); |
| if (!err) |
| err = xenbus_printf(trans, pdev->xdev->nodename, |
| "magic", XEN_PCI_MAGIC); |
| |
| if (err) { |
| xenbus_transaction_end(trans, 1); |
| xenbus_dev_fatal(pdev->xdev, err, |
| "Error writing configuration for backend"); |
| goto out; |
| } else { |
| err = xenbus_transaction_end(trans, 0); |
| if (err == -EAGAIN) |
| goto do_publish; |
| else if (err) { |
| xenbus_dev_fatal(pdev->xdev, err, |
| "Error completing transaction " |
| "for backend"); |
| goto out; |
| } |
| } |
| |
| xenbus_switch_state(pdev->xdev, XenbusStateInitialised); |
| |
| dev_dbg(&pdev->xdev->dev, "publishing successful!\n"); |
| |
| out: |
| return err; |
| } |
| |
| static int pcifront_try_connect(struct pcifront_device *pdev) |
| { |
| int err = -EFAULT; |
| int i, num_roots, len; |
| char str[64]; |
| unsigned int domain, bus; |
| |
| |
| /* Only connect once */ |
| if (xenbus_read_driver_state(pdev->xdev->nodename) != |
| XenbusStateInitialised) |
| goto out; |
| |
| err = pcifront_connect_and_init_dma(pdev); |
| if (err && err != -EEXIST) { |
| xenbus_dev_fatal(pdev->xdev, err, |
| "Error setting up PCI Frontend"); |
| goto out; |
| } |
| |
| err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, |
| "root_num", "%d", &num_roots); |
| if (err == -ENOENT) { |
| xenbus_dev_error(pdev->xdev, err, |
| "No PCI Roots found, trying 0000:00"); |
| err = pcifront_scan_root(pdev, 0, 0); |
| num_roots = 0; |
| } else if (err != 1) { |
| if (err == 0) |
| err = -EINVAL; |
| xenbus_dev_fatal(pdev->xdev, err, |
| "Error reading number of PCI roots"); |
| goto out; |
| } |
| |
| for (i = 0; i < num_roots; 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->otherend, str, |
| "%x:%x", &domain, &bus); |
| if (err != 2) { |
| if (err >= 0) |
| err = -EINVAL; |
| xenbus_dev_fatal(pdev->xdev, err, |
| "Error reading PCI root %d", i); |
| goto out; |
| } |
| |
| err = pcifront_scan_root(pdev, domain, bus); |
| if (err) { |
| xenbus_dev_fatal(pdev->xdev, err, |
| "Error scanning PCI root %04x:%02x", |
| domain, bus); |
| goto out; |
| } |
| } |
| |
| err = xenbus_switch_state(pdev->xdev, XenbusStateConnected); |
| |
| out: |
| return err; |
| } |
| |
| static int pcifront_try_disconnect(struct pcifront_device *pdev) |
| { |
| int err = 0; |
| enum xenbus_state prev_state; |
| |
| |
| prev_state = xenbus_read_driver_state(pdev->xdev->nodename); |
| |
| if (prev_state >= XenbusStateClosing) |
| goto out; |
| |
| if (prev_state == XenbusStateConnected) { |
| pcifront_free_roots(pdev); |
| pcifront_disconnect(pdev); |
| } |
| |
| err = xenbus_switch_state(pdev->xdev, XenbusStateClosed); |
| |
| out: |
| |
| return err; |
| } |
| |
| static int pcifront_attach_devices(struct pcifront_device *pdev) |
| { |
| int err = -EFAULT; |
| int i, num_roots, len; |
| unsigned int domain, bus; |
| char str[64]; |
| |
| if (xenbus_read_driver_state(pdev->xdev->nodename) != |
| XenbusStateReconfiguring) |
| goto out; |
| |
| err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, |
| "root_num", "%d", &num_roots); |
| if (err == -ENOENT) { |
| xenbus_dev_error(pdev->xdev, err, |
| "No PCI Roots found, trying 0000:00"); |
| err = pcifront_rescan_root(pdev, 0, 0); |
| num_roots = 0; |
| } else if (err != 1) { |
| if (err == 0) |
| err = -EINVAL; |
| xenbus_dev_fatal(pdev->xdev, err, |
| "Error reading number of PCI roots"); |
| goto out; |
| } |
| |
| for (i = 0; i < num_roots; 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->otherend, str, |
| "%x:%x", &domain, &bus); |
| if (err != 2) { |
| if (err >= 0) |
| err = -EINVAL; |
| xenbus_dev_fatal(pdev->xdev, err, |
| "Error reading PCI root %d", i); |
| goto out; |
| } |
| |
| err = pcifront_rescan_root(pdev, domain, bus); |
| if (err) { |
| xenbus_dev_fatal(pdev->xdev, err, |
| "Error scanning PCI root %04x:%02x", |
| domain, bus); |
| goto out; |
| } |
| } |
| |
| xenbus_switch_state(pdev->xdev, XenbusStateConnected); |
| |
| out: |
| return err; |
| } |
| |
| static int pcifront_detach_devices(struct pcifront_device *pdev) |
| { |
| int err = 0; |
| int i, num_devs; |
| unsigned int domain, bus, slot, func; |
| struct pci_dev *pci_dev; |
| char str[64]; |
| |
| if (xenbus_read_driver_state(pdev->xdev->nodename) != |
| XenbusStateConnected) |
| goto out; |
| |
| err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, "num_devs", "%d", |
| &num_devs); |
| if (err != 1) { |
| if (err >= 0) |
| err = -EINVAL; |
| xenbus_dev_fatal(pdev->xdev, err, |
| "Error reading number of PCI devices"); |
| goto out; |
| } |
| |
| /* Find devices being detached and remove them. */ |
| for (i = 0; i < num_devs; i++) { |
| int l, state; |
| l = snprintf(str, sizeof(str), "state-%d", i); |
| if (unlikely(l >= (sizeof(str) - 1))) { |
| err = -ENOMEM; |
| goto out; |
| } |
| err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str, "%d", |
| &state); |
| if (err != 1) |
| state = XenbusStateUnknown; |
| |
| if (state != XenbusStateClosing) |
| continue; |
| |
| /* Remove device. */ |
| l = snprintf(str, sizeof(str), "vdev-%d", i); |
| if (unlikely(l >= (sizeof(str) - 1))) { |
| err = -ENOMEM; |
| goto out; |
| } |
| err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str, |
| "%x:%x:%x.%x", &domain, &bus, &slot, &func); |
| if (err != 4) { |
| if (err >= 0) |
| err = -EINVAL; |
| xenbus_dev_fatal(pdev->xdev, err, |
| "Error reading PCI device %d", i); |
| goto out; |
| } |
| |
| pci_dev = pci_get_domain_bus_and_slot(domain, bus, |
| PCI_DEVFN(slot, func)); |
| if (!pci_dev) { |
| dev_dbg(&pdev->xdev->dev, |
| "Cannot get PCI device %04x:%02x:%02x.%d\n", |
| domain, bus, slot, func); |
| continue; |
| } |
| pci_lock_rescan_remove(); |
| pci_stop_and_remove_bus_device(pci_dev); |
| pci_dev_put(pci_dev); |
| pci_unlock_rescan_remove(); |
| |
| dev_dbg(&pdev->xdev->dev, |
| "PCI device %04x:%02x:%02x.%d removed.\n", |
| domain, bus, slot, func); |
| } |
| |
| err = xenbus_switch_state(pdev->xdev, XenbusStateReconfiguring); |
| |
| out: |
| return err; |
| } |
| |
| static void __init_refok pcifront_backend_changed(struct xenbus_device *xdev, |
| enum xenbus_state be_state) |
| { |
| struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev); |
| |
| switch (be_state) { |
| case XenbusStateUnknown: |
| case XenbusStateInitialising: |
| case XenbusStateInitWait: |
| case XenbusStateInitialised: |
| break; |
| |
| case XenbusStateConnected: |
| pcifront_try_connect(pdev); |
| break; |
| |
| case XenbusStateClosed: |
| if (xdev->state == XenbusStateClosed) |
| break; |
| /* Missed the backend's CLOSING state -- fallthrough */ |
| case XenbusStateClosing: |
| dev_warn(&xdev->dev, "backend going away!\n"); |
| pcifront_try_disconnect(pdev); |
| break; |
| |
| case XenbusStateReconfiguring: |
| pcifront_detach_devices(pdev); |
| break; |
| |
| case XenbusStateReconfigured: |
| pcifront_attach_devices(pdev); |
| break; |
| } |
| } |
| |
| static int pcifront_xenbus_probe(struct xenbus_device *xdev, |
| const struct xenbus_device_id *id) |
| { |
| int err = 0; |
| struct pcifront_device *pdev = alloc_pdev(xdev); |
| |
| if (pdev == NULL) { |
| err = -ENOMEM; |
| xenbus_dev_fatal(xdev, err, |
| "Error allocating pcifront_device struct"); |
| goto out; |
| } |
| |
| err = pcifront_publish_info(pdev); |
| if (err) |
| free_pdev(pdev); |
| |
| out: |
| return err; |
| } |
| |
| static int pcifront_xenbus_remove(struct xenbus_device *xdev) |
| { |
| struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev); |
| if (pdev) |
| free_pdev(pdev); |
| |
| return 0; |
| } |
| |
| static const struct xenbus_device_id xenpci_ids[] = { |
| {"pci"}, |
| {""}, |
| }; |
| |
| static DEFINE_XENBUS_DRIVER(xenpci, "pcifront", |
| .probe = pcifront_xenbus_probe, |
| .remove = pcifront_xenbus_remove, |
| .otherend_changed = pcifront_backend_changed, |
| ); |
| |
| static int __init pcifront_init(void) |
| { |
| if (!xen_pv_domain() || xen_initial_domain()) |
| return -ENODEV; |
| |
| pci_frontend_registrar(1 /* enable */); |
| |
| return xenbus_register_frontend(&xenpci_driver); |
| } |
| |
| static void __exit pcifront_cleanup(void) |
| { |
| xenbus_unregister_driver(&xenpci_driver); |
| pci_frontend_registrar(0 /* disable */); |
| } |
| module_init(pcifront_init); |
| module_exit(pcifront_cleanup); |
| |
| MODULE_DESCRIPTION("Xen PCI passthrough frontend."); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS("xen:pci"); |