4 * Author: Ryan Wilson <hap9@epoch.ncsc.mil>
6 #include <linux/module.h>
7 #include <linux/init.h>
9 #include <xen/xenbus.h>
10 #include <xen/events.h>
11 #include <xen/grant_table.h>
13 #include <linux/spinlock.h>
14 #include <linux/pci.h>
15 #include <linux/msi.h>
16 #include <xen/interface/io/pciif.h>
17 #include <asm/xen/pci.h>
18 #include <linux/interrupt.h>
19 #include <linux/atomic.h>
20 #include <linux/workqueue.h>
21 #include <linux/bitops.h>
22 #include <linux/time.h>
24 #include <asm/xen/swiotlb-xen.h>
25 #define INVALID_GRANT_REF (0)
26 #define INVALID_EVTCHN (-1)
28 struct pci_bus_entry {
29 struct list_head list;
33 #define _PDEVB_op_active (0)
34 #define PDEVB_op_active (1 << (_PDEVB_op_active))
36 struct pcifront_device {
37 struct xenbus_device *xdev;
38 struct list_head root_buses;
45 /* Lock this when doing any operations in sh_info */
46 spinlock_t sh_info_lock;
47 struct xen_pci_sharedinfo *sh_info;
48 struct work_struct op_work;
55 struct pcifront_device *pdev;
58 static inline struct pcifront_device *
59 pcifront_get_pdev(struct pcifront_sd *sd)
64 static inline void pcifront_init_sd(struct pcifront_sd *sd,
65 unsigned int domain, unsigned int bus,
66 struct pcifront_device *pdev)
72 static DEFINE_SPINLOCK(pcifront_dev_lock);
73 static struct pcifront_device *pcifront_dev;
75 static int verbose_request;
76 module_param(verbose_request, int, 0644);
78 static int errno_to_pcibios_err(int errno)
81 case XEN_PCI_ERR_success:
82 return PCIBIOS_SUCCESSFUL;
84 case XEN_PCI_ERR_dev_not_found:
85 return PCIBIOS_DEVICE_NOT_FOUND;
87 case XEN_PCI_ERR_invalid_offset:
88 case XEN_PCI_ERR_op_failed:
89 return PCIBIOS_BAD_REGISTER_NUMBER;
91 case XEN_PCI_ERR_not_implemented:
92 return PCIBIOS_FUNC_NOT_SUPPORTED;
94 case XEN_PCI_ERR_access_denied:
95 return PCIBIOS_SET_FAILED;
100 static inline void schedule_pcifront_aer_op(struct pcifront_device *pdev)
102 if (test_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags)
103 && !test_and_set_bit(_PDEVB_op_active, &pdev->flags)) {
104 dev_dbg(&pdev->xdev->dev, "schedule aer frontend job\n");
105 schedule_work(&pdev->op_work);
109 static int do_pci_op(struct pcifront_device *pdev, struct xen_pci_op *op)
112 struct xen_pci_op *active_op = &pdev->sh_info->op;
113 unsigned long irq_flags;
114 evtchn_port_t port = pdev->evtchn;
115 unsigned irq = pdev->irq;
119 spin_lock_irqsave(&pdev->sh_info_lock, irq_flags);
121 memcpy(active_op, op, sizeof(struct xen_pci_op));
125 set_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags);
126 notify_remote_via_evtchn(port);
129 * We set a poll timeout of 3 seconds but give up on return after
130 * 2 seconds. It is better to time out too late rather than too early
131 * (in the latter case we end up continually re-executing poll() with a
132 * timeout in the past). 1s difference gives plenty of slack for error.
134 do_gettimeofday(&tv);
135 ns_timeout = timeval_to_ns(&tv) + 2 * (s64)NSEC_PER_SEC;
137 xen_clear_irq_pending(irq);
139 while (test_bit(_XEN_PCIF_active,
140 (unsigned long *)&pdev->sh_info->flags)) {
141 xen_poll_irq_timeout(irq, jiffies + 3*HZ);
142 xen_clear_irq_pending(irq);
143 do_gettimeofday(&tv);
144 ns = timeval_to_ns(&tv);
145 if (ns > ns_timeout) {
146 dev_err(&pdev->xdev->dev,
147 "pciback not responding!!!\n");
148 clear_bit(_XEN_PCIF_active,
149 (unsigned long *)&pdev->sh_info->flags);
150 err = XEN_PCI_ERR_dev_not_found;
156 * We might lose backend service request since we
157 * reuse same evtchn with pci_conf backend response. So re-schedule
158 * aer pcifront service.
160 if (test_bit(_XEN_PCIB_active,
161 (unsigned long *)&pdev->sh_info->flags)) {
162 dev_err(&pdev->xdev->dev,
163 "schedule aer pcifront service\n");
164 schedule_pcifront_aer_op(pdev);
167 memcpy(op, active_op, sizeof(struct xen_pci_op));
171 spin_unlock_irqrestore(&pdev->sh_info_lock, irq_flags);
175 /* Access to this function is spinlocked in drivers/pci/access.c */
176 static int pcifront_bus_read(struct pci_bus *bus, unsigned int devfn,
177 int where, int size, u32 *val)
180 struct xen_pci_op op = {
181 .cmd = XEN_PCI_OP_conf_read,
182 .domain = pci_domain_nr(bus),
188 struct pcifront_sd *sd = bus->sysdata;
189 struct pcifront_device *pdev = pcifront_get_pdev(sd);
192 dev_info(&pdev->xdev->dev,
193 "read dev=%04x:%02x:%02x.%d - offset %x size %d\n",
194 pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),
195 PCI_FUNC(devfn), where, size);
197 err = do_pci_op(pdev, &op);
201 dev_info(&pdev->xdev->dev, "read got back value %x\n",
205 } else if (err == -ENODEV) {
206 /* No device here, pretend that it just returned 0 */
211 return errno_to_pcibios_err(err);
214 /* Access to this function is spinlocked in drivers/pci/access.c */
215 static int pcifront_bus_write(struct pci_bus *bus, unsigned int devfn,
216 int where, int size, u32 val)
218 struct xen_pci_op op = {
219 .cmd = XEN_PCI_OP_conf_write,
220 .domain = pci_domain_nr(bus),
227 struct pcifront_sd *sd = bus->sysdata;
228 struct pcifront_device *pdev = pcifront_get_pdev(sd);
231 dev_info(&pdev->xdev->dev,
232 "write dev=%04x:%02x:%02x.%d - "
233 "offset %x size %d val %x\n",
234 pci_domain_nr(bus), bus->number,
235 PCI_SLOT(devfn), PCI_FUNC(devfn), where, size, val);
237 return errno_to_pcibios_err(do_pci_op(pdev, &op));
240 static struct pci_ops pcifront_bus_ops = {
241 .read = pcifront_bus_read,
242 .write = pcifront_bus_write,
245 #ifdef CONFIG_PCI_MSI
246 static int pci_frontend_enable_msix(struct pci_dev *dev,
247 int vector[], int nvec)
251 struct xen_pci_op op = {
252 .cmd = XEN_PCI_OP_enable_msix,
253 .domain = pci_domain_nr(dev->bus),
254 .bus = dev->bus->number,
258 struct pcifront_sd *sd = dev->bus->sysdata;
259 struct pcifront_device *pdev = pcifront_get_pdev(sd);
260 struct msi_desc *entry;
262 if (nvec > SH_INFO_MAX_VEC) {
263 dev_err(&dev->dev, "too much vector for pci frontend: %x."
264 " Increase SH_INFO_MAX_VEC.\n", nvec);
269 list_for_each_entry(entry, &dev->msi_list, list) {
270 op.msix_entries[i].entry = entry->msi_attrib.entry_nr;
271 /* Vector is useless at this point. */
272 op.msix_entries[i].vector = -1;
276 err = do_pci_op(pdev, &op);
279 if (likely(!op.value)) {
280 /* we get the result */
281 for (i = 0; i < nvec; i++) {
282 if (op.msix_entries[i].vector <= 0) {
283 dev_warn(&dev->dev, "MSI-X entry %d is invalid: %d!\n",
284 i, op.msix_entries[i].vector);
289 vector[i] = op.msix_entries[i].vector;
292 printk(KERN_DEBUG "enable msix get value %x\n",
297 dev_err(&dev->dev, "enable msix get err %x\n", err);
302 static void pci_frontend_disable_msix(struct pci_dev *dev)
305 struct xen_pci_op op = {
306 .cmd = XEN_PCI_OP_disable_msix,
307 .domain = pci_domain_nr(dev->bus),
308 .bus = dev->bus->number,
311 struct pcifront_sd *sd = dev->bus->sysdata;
312 struct pcifront_device *pdev = pcifront_get_pdev(sd);
314 err = do_pci_op(pdev, &op);
316 /* What should do for error ? */
318 dev_err(&dev->dev, "pci_disable_msix get err %x\n", err);
321 static int pci_frontend_enable_msi(struct pci_dev *dev, int vector[])
324 struct xen_pci_op op = {
325 .cmd = XEN_PCI_OP_enable_msi,
326 .domain = pci_domain_nr(dev->bus),
327 .bus = dev->bus->number,
330 struct pcifront_sd *sd = dev->bus->sysdata;
331 struct pcifront_device *pdev = pcifront_get_pdev(sd);
333 err = do_pci_op(pdev, &op);
335 vector[0] = op.value;
337 dev_warn(&dev->dev, "MSI entry is invalid: %d!\n",
343 dev_err(&dev->dev, "pci frontend enable msi failed for dev "
344 "%x:%x\n", op.bus, op.devfn);
350 static void pci_frontend_disable_msi(struct pci_dev *dev)
353 struct xen_pci_op op = {
354 .cmd = XEN_PCI_OP_disable_msi,
355 .domain = pci_domain_nr(dev->bus),
356 .bus = dev->bus->number,
359 struct pcifront_sd *sd = dev->bus->sysdata;
360 struct pcifront_device *pdev = pcifront_get_pdev(sd);
362 err = do_pci_op(pdev, &op);
363 if (err == XEN_PCI_ERR_dev_not_found) {
364 /* XXX No response from backend, what shall we do? */
365 printk(KERN_DEBUG "get no response from backend for disable MSI\n");
369 /* how can pciback notify us fail? */
370 printk(KERN_DEBUG "get fake response frombackend\n");
373 static struct xen_pci_frontend_ops pci_frontend_ops = {
374 .enable_msi = pci_frontend_enable_msi,
375 .disable_msi = pci_frontend_disable_msi,
376 .enable_msix = pci_frontend_enable_msix,
377 .disable_msix = pci_frontend_disable_msix,
380 static void pci_frontend_registrar(int enable)
383 xen_pci_frontend = &pci_frontend_ops;
385 xen_pci_frontend = NULL;
388 static inline void pci_frontend_registrar(int enable) { };
389 #endif /* CONFIG_PCI_MSI */
391 /* Claim resources for the PCI frontend as-is, backend won't allow changes */
392 static int pcifront_claim_resource(struct pci_dev *dev, void *data)
394 struct pcifront_device *pdev = data;
398 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
399 r = &dev->resource[i];
401 if (!r->parent && r->start && r->flags) {
402 dev_info(&pdev->xdev->dev, "claiming resource %s/%d\n",
404 if (pci_claim_resource(dev, i)) {
405 dev_err(&pdev->xdev->dev, "Could not claim resource %s/%d! "
406 "Device offline. Try using e820_host=1 in the guest config.\n",
415 static int pcifront_scan_bus(struct pcifront_device *pdev,
416 unsigned int domain, unsigned int bus,
422 /* Scan the bus for functions and add.
423 * We omit handling of PCI bridge attachment because pciback prevents
424 * bridges from being exported.
426 for (devfn = 0; devfn < 0x100; devfn++) {
427 d = pci_get_slot(b, devfn);
429 /* Device is already known. */
434 d = pci_scan_single_device(b, devfn);
436 dev_info(&pdev->xdev->dev, "New device on "
437 "%04x:%02x:%02x.%d found.\n", domain, bus,
438 PCI_SLOT(devfn), PCI_FUNC(devfn));
444 static int pcifront_scan_root(struct pcifront_device *pdev,
445 unsigned int domain, unsigned int bus)
448 struct pcifront_sd *sd = NULL;
449 struct pci_bus_entry *bus_entry = NULL;
452 #ifndef CONFIG_PCI_DOMAINS
454 dev_err(&pdev->xdev->dev,
455 "PCI Root in non-zero PCI Domain! domain=%d\n", domain);
456 dev_err(&pdev->xdev->dev,
457 "Please compile with CONFIG_PCI_DOMAINS\n");
463 dev_info(&pdev->xdev->dev, "Creating PCI Frontend Bus %04x:%02x\n",
466 bus_entry = kmalloc(sizeof(*bus_entry), GFP_KERNEL);
467 sd = kmalloc(sizeof(*sd), GFP_KERNEL);
468 if (!bus_entry || !sd) {
472 pcifront_init_sd(sd, domain, bus, pdev);
474 b = pci_scan_bus_parented(&pdev->xdev->dev, bus,
475 &pcifront_bus_ops, sd);
477 dev_err(&pdev->xdev->dev,
478 "Error creating PCI Frontend Bus!\n");
485 list_add(&bus_entry->list, &pdev->root_buses);
487 /* pci_scan_bus_parented skips devices which do not have a have
488 * devfn==0. The pcifront_scan_bus enumerates all devfn. */
489 err = pcifront_scan_bus(pdev, domain, bus, b);
491 /* Claim resources before going "live" with our devices */
492 pci_walk_bus(b, pcifront_claim_resource, pdev);
494 /* Create SysFS and notify udev of the devices. Aka: "going live" */
495 pci_bus_add_devices(b);
506 static int pcifront_rescan_root(struct pcifront_device *pdev,
507 unsigned int domain, unsigned int bus)
512 #ifndef CONFIG_PCI_DOMAINS
514 dev_err(&pdev->xdev->dev,
515 "PCI Root in non-zero PCI Domain! domain=%d\n", domain);
516 dev_err(&pdev->xdev->dev,
517 "Please compile with CONFIG_PCI_DOMAINS\n");
522 dev_info(&pdev->xdev->dev, "Rescanning PCI Frontend Bus %04x:%02x\n",
525 b = pci_find_bus(domain, bus);
527 /* If the bus is unknown, create it. */
528 return pcifront_scan_root(pdev, domain, bus);
530 err = pcifront_scan_bus(pdev, domain, bus, b);
532 /* Claim resources before going "live" with our devices */
533 pci_walk_bus(b, pcifront_claim_resource, pdev);
535 /* Create SysFS and notify udev of the devices. Aka: "going live" */
536 pci_bus_add_devices(b);
541 static void free_root_bus_devs(struct pci_bus *bus)
545 while (!list_empty(&bus->devices)) {
546 dev = container_of(bus->devices.next, struct pci_dev,
548 dev_dbg(&dev->dev, "removing device\n");
549 pci_stop_and_remove_bus_device(dev);
553 static void pcifront_free_roots(struct pcifront_device *pdev)
555 struct pci_bus_entry *bus_entry, *t;
557 dev_dbg(&pdev->xdev->dev, "cleaning up root buses\n");
559 list_for_each_entry_safe(bus_entry, t, &pdev->root_buses, list) {
560 list_del(&bus_entry->list);
562 free_root_bus_devs(bus_entry->bus);
564 kfree(bus_entry->bus->sysdata);
566 device_unregister(bus_entry->bus->bridge);
567 pci_remove_bus(bus_entry->bus);
573 static pci_ers_result_t pcifront_common_process(int cmd,
574 struct pcifront_device *pdev,
575 pci_channel_state_t state)
577 pci_ers_result_t result;
578 struct pci_driver *pdrv;
579 int bus = pdev->sh_info->aer_op.bus;
580 int devfn = pdev->sh_info->aer_op.devfn;
581 struct pci_dev *pcidev;
584 dev_dbg(&pdev->xdev->dev,
585 "pcifront AER process: cmd %x (bus:%x, devfn%x)",
587 result = PCI_ERS_RESULT_NONE;
589 pcidev = pci_get_bus_and_slot(bus, devfn);
590 if (!pcidev || !pcidev->driver) {
591 dev_err(&pdev->xdev->dev, "device or AER driver is NULL\n");
596 pdrv = pcidev->driver;
599 if (pdrv->err_handler && pdrv->err_handler->error_detected) {
600 dev_dbg(&pcidev->dev,
601 "trying to call AER service\n");
605 case XEN_PCI_OP_aer_detected:
606 result = pdrv->err_handler->
607 error_detected(pcidev, state);
609 case XEN_PCI_OP_aer_mmio:
610 result = pdrv->err_handler->
611 mmio_enabled(pcidev);
613 case XEN_PCI_OP_aer_slotreset:
614 result = pdrv->err_handler->
617 case XEN_PCI_OP_aer_resume:
618 pdrv->err_handler->resume(pcidev);
621 dev_err(&pdev->xdev->dev,
622 "bad request in aer recovery "
630 result = PCI_ERS_RESULT_NONE;
636 static void pcifront_do_aer(struct work_struct *data)
638 struct pcifront_device *pdev =
639 container_of(data, struct pcifront_device, op_work);
640 int cmd = pdev->sh_info->aer_op.cmd;
641 pci_channel_state_t state =
642 (pci_channel_state_t)pdev->sh_info->aer_op.err;
644 /*If a pci_conf op is in progress,
645 we have to wait until it is done before service aer op*/
646 dev_dbg(&pdev->xdev->dev,
647 "pcifront service aer bus %x devfn %x\n",
648 pdev->sh_info->aer_op.bus, pdev->sh_info->aer_op.devfn);
650 pdev->sh_info->aer_op.err = pcifront_common_process(cmd, pdev, state);
652 /* Post the operation to the guest. */
654 clear_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags);
655 notify_remote_via_evtchn(pdev->evtchn);
657 /*in case of we lost an aer request in four lines time_window*/
658 smp_mb__before_clear_bit();
659 clear_bit(_PDEVB_op_active, &pdev->flags);
660 smp_mb__after_clear_bit();
662 schedule_pcifront_aer_op(pdev);
666 static irqreturn_t pcifront_handler_aer(int irq, void *dev)
668 struct pcifront_device *pdev = dev;
669 schedule_pcifront_aer_op(pdev);
672 static int pcifront_connect_and_init_dma(struct pcifront_device *pdev)
676 spin_lock(&pcifront_dev_lock);
679 dev_info(&pdev->xdev->dev, "Installing PCI frontend\n");
682 dev_err(&pdev->xdev->dev, "PCI frontend already installed!\n");
685 spin_unlock(&pcifront_dev_lock);
687 if (!err && !swiotlb_nr_tbl()) {
688 err = pci_xen_swiotlb_init_late();
690 dev_err(&pdev->xdev->dev, "Could not setup SWIOTLB!\n");
695 static void pcifront_disconnect(struct pcifront_device *pdev)
697 spin_lock(&pcifront_dev_lock);
699 if (pdev == pcifront_dev) {
700 dev_info(&pdev->xdev->dev,
701 "Disconnecting PCI Frontend Buses\n");
705 spin_unlock(&pcifront_dev_lock);
707 static struct pcifront_device *alloc_pdev(struct xenbus_device *xdev)
709 struct pcifront_device *pdev;
711 pdev = kzalloc(sizeof(struct pcifront_device), GFP_KERNEL);
716 (struct xen_pci_sharedinfo *)__get_free_page(GFP_KERNEL);
717 if (pdev->sh_info == NULL) {
722 pdev->sh_info->flags = 0;
724 /*Flag for registering PV AER handler*/
725 set_bit(_XEN_PCIB_AERHANDLER, (void *)&pdev->sh_info->flags);
727 dev_set_drvdata(&xdev->dev, pdev);
730 INIT_LIST_HEAD(&pdev->root_buses);
732 spin_lock_init(&pdev->sh_info_lock);
734 pdev->evtchn = INVALID_EVTCHN;
735 pdev->gnt_ref = INVALID_GRANT_REF;
738 INIT_WORK(&pdev->op_work, pcifront_do_aer);
740 dev_dbg(&xdev->dev, "Allocated pdev @ 0x%p pdev->sh_info @ 0x%p\n",
741 pdev, pdev->sh_info);
746 static void free_pdev(struct pcifront_device *pdev)
748 dev_dbg(&pdev->xdev->dev, "freeing pdev @ 0x%p\n", pdev);
750 pcifront_free_roots(pdev);
752 cancel_work_sync(&pdev->op_work);
755 unbind_from_irqhandler(pdev->irq, pdev);
757 if (pdev->evtchn != INVALID_EVTCHN)
758 xenbus_free_evtchn(pdev->xdev, pdev->evtchn);
760 if (pdev->gnt_ref != INVALID_GRANT_REF)
761 gnttab_end_foreign_access(pdev->gnt_ref, 0 /* r/w page */,
762 (unsigned long)pdev->sh_info);
764 free_page((unsigned long)pdev->sh_info);
766 dev_set_drvdata(&pdev->xdev->dev, NULL);
771 static int pcifront_publish_info(struct pcifront_device *pdev)
774 struct xenbus_transaction trans;
776 err = xenbus_grant_ring(pdev->xdev, virt_to_mfn(pdev->sh_info));
782 err = xenbus_alloc_evtchn(pdev->xdev, &pdev->evtchn);
786 err = bind_evtchn_to_irqhandler(pdev->evtchn, pcifront_handler_aer,
787 0, "pcifront", pdev);
795 err = xenbus_transaction_start(&trans);
797 xenbus_dev_fatal(pdev->xdev, err,
798 "Error writing configuration for backend "
799 "(start transaction)");
803 err = xenbus_printf(trans, pdev->xdev->nodename,
804 "pci-op-ref", "%u", pdev->gnt_ref);
806 err = xenbus_printf(trans, pdev->xdev->nodename,
807 "event-channel", "%u", pdev->evtchn);
809 err = xenbus_printf(trans, pdev->xdev->nodename,
810 "magic", XEN_PCI_MAGIC);
813 xenbus_transaction_end(trans, 1);
814 xenbus_dev_fatal(pdev->xdev, err,
815 "Error writing configuration for backend");
818 err = xenbus_transaction_end(trans, 0);
822 xenbus_dev_fatal(pdev->xdev, err,
823 "Error completing transaction "
829 xenbus_switch_state(pdev->xdev, XenbusStateInitialised);
831 dev_dbg(&pdev->xdev->dev, "publishing successful!\n");
837 static int pcifront_try_connect(struct pcifront_device *pdev)
840 int i, num_roots, len;
842 unsigned int domain, bus;
845 /* Only connect once */
846 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
847 XenbusStateInitialised)
850 err = pcifront_connect_and_init_dma(pdev);
852 xenbus_dev_fatal(pdev->xdev, err,
853 "Error setting up PCI Frontend");
857 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
858 "root_num", "%d", &num_roots);
859 if (err == -ENOENT) {
860 xenbus_dev_error(pdev->xdev, err,
861 "No PCI Roots found, trying 0000:00");
862 err = pcifront_scan_root(pdev, 0, 0);
864 } else if (err != 1) {
867 xenbus_dev_fatal(pdev->xdev, err,
868 "Error reading number of PCI roots");
872 for (i = 0; i < num_roots; i++) {
873 len = snprintf(str, sizeof(str), "root-%d", i);
874 if (unlikely(len >= (sizeof(str) - 1))) {
879 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
880 "%x:%x", &domain, &bus);
884 xenbus_dev_fatal(pdev->xdev, err,
885 "Error reading PCI root %d", i);
889 err = pcifront_scan_root(pdev, domain, bus);
891 xenbus_dev_fatal(pdev->xdev, err,
892 "Error scanning PCI root %04x:%02x",
898 err = xenbus_switch_state(pdev->xdev, XenbusStateConnected);
904 static int pcifront_try_disconnect(struct pcifront_device *pdev)
907 enum xenbus_state prev_state;
910 prev_state = xenbus_read_driver_state(pdev->xdev->nodename);
912 if (prev_state >= XenbusStateClosing)
915 if (prev_state == XenbusStateConnected) {
916 pcifront_free_roots(pdev);
917 pcifront_disconnect(pdev);
920 err = xenbus_switch_state(pdev->xdev, XenbusStateClosed);
927 static int pcifront_attach_devices(struct pcifront_device *pdev)
930 int i, num_roots, len;
931 unsigned int domain, bus;
934 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
935 XenbusStateReconfiguring)
938 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
939 "root_num", "%d", &num_roots);
940 if (err == -ENOENT) {
941 xenbus_dev_error(pdev->xdev, err,
942 "No PCI Roots found, trying 0000:00");
943 err = pcifront_rescan_root(pdev, 0, 0);
945 } else if (err != 1) {
948 xenbus_dev_fatal(pdev->xdev, err,
949 "Error reading number of PCI roots");
953 for (i = 0; i < num_roots; i++) {
954 len = snprintf(str, sizeof(str), "root-%d", i);
955 if (unlikely(len >= (sizeof(str) - 1))) {
960 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
961 "%x:%x", &domain, &bus);
965 xenbus_dev_fatal(pdev->xdev, err,
966 "Error reading PCI root %d", i);
970 err = pcifront_rescan_root(pdev, domain, bus);
972 xenbus_dev_fatal(pdev->xdev, err,
973 "Error scanning PCI root %04x:%02x",
979 xenbus_switch_state(pdev->xdev, XenbusStateConnected);
985 static int pcifront_detach_devices(struct pcifront_device *pdev)
989 unsigned int domain, bus, slot, func;
990 struct pci_dev *pci_dev;
993 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
994 XenbusStateConnected)
997 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, "num_devs", "%d",
1002 xenbus_dev_fatal(pdev->xdev, err,
1003 "Error reading number of PCI devices");
1007 /* Find devices being detached and remove them. */
1008 for (i = 0; i < num_devs; i++) {
1010 l = snprintf(str, sizeof(str), "state-%d", i);
1011 if (unlikely(l >= (sizeof(str) - 1))) {
1015 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str, "%d",
1018 state = XenbusStateUnknown;
1020 if (state != XenbusStateClosing)
1023 /* Remove device. */
1024 l = snprintf(str, sizeof(str), "vdev-%d", i);
1025 if (unlikely(l >= (sizeof(str) - 1))) {
1029 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
1030 "%x:%x:%x.%x", &domain, &bus, &slot, &func);
1034 xenbus_dev_fatal(pdev->xdev, err,
1035 "Error reading PCI device %d", i);
1039 pci_dev = pci_get_domain_bus_and_slot(domain, bus,
1040 PCI_DEVFN(slot, func));
1042 dev_dbg(&pdev->xdev->dev,
1043 "Cannot get PCI device %04x:%02x:%02x.%d\n",
1044 domain, bus, slot, func);
1047 pci_stop_and_remove_bus_device(pci_dev);
1048 pci_dev_put(pci_dev);
1050 dev_dbg(&pdev->xdev->dev,
1051 "PCI device %04x:%02x:%02x.%d removed.\n",
1052 domain, bus, slot, func);
1055 err = xenbus_switch_state(pdev->xdev, XenbusStateReconfiguring);
1061 static void __init_refok pcifront_backend_changed(struct xenbus_device *xdev,
1062 enum xenbus_state be_state)
1064 struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev);
1067 case XenbusStateUnknown:
1068 case XenbusStateInitialising:
1069 case XenbusStateInitWait:
1070 case XenbusStateInitialised:
1073 case XenbusStateConnected:
1074 pcifront_try_connect(pdev);
1077 case XenbusStateClosed:
1078 if (xdev->state == XenbusStateClosed)
1080 /* Missed the backend's CLOSING state -- fallthrough */
1081 case XenbusStateClosing:
1082 dev_warn(&xdev->dev, "backend going away!\n");
1083 pcifront_try_disconnect(pdev);
1086 case XenbusStateReconfiguring:
1087 pcifront_detach_devices(pdev);
1090 case XenbusStateReconfigured:
1091 pcifront_attach_devices(pdev);
1096 static int pcifront_xenbus_probe(struct xenbus_device *xdev,
1097 const struct xenbus_device_id *id)
1100 struct pcifront_device *pdev = alloc_pdev(xdev);
1104 xenbus_dev_fatal(xdev, err,
1105 "Error allocating pcifront_device struct");
1109 err = pcifront_publish_info(pdev);
1117 static int pcifront_xenbus_remove(struct xenbus_device *xdev)
1119 struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev);
1126 static const struct xenbus_device_id xenpci_ids[] = {
1131 static DEFINE_XENBUS_DRIVER(xenpci, "pcifront",
1132 .probe = pcifront_xenbus_probe,
1133 .remove = pcifront_xenbus_remove,
1134 .otherend_changed = pcifront_backend_changed,
1137 static int __init pcifront_init(void)
1139 if (!xen_pv_domain() || xen_initial_domain())
1142 pci_frontend_registrar(1 /* enable */);
1144 return xenbus_register_frontend(&xenpci_driver);
1147 static void __exit pcifront_cleanup(void)
1149 xenbus_unregister_driver(&xenpci_driver);
1150 pci_frontend_registrar(0 /* disable */);
1152 module_init(pcifront_init);
1153 module_exit(pcifront_cleanup);
1155 MODULE_DESCRIPTION("Xen PCI passthrough frontend.");
1156 MODULE_LICENSE("GPL");
1157 MODULE_ALIAS("xen:pci");