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>
23 #include <xen/platform_pci.h>
25 #include <asm/xen/swiotlb-xen.h>
26 #define INVALID_GRANT_REF (0)
27 #define INVALID_EVTCHN (-1)
29 struct pci_bus_entry {
30 struct list_head list;
34 #define _PDEVB_op_active (0)
35 #define PDEVB_op_active (1 << (_PDEVB_op_active))
37 struct pcifront_device {
38 struct xenbus_device *xdev;
39 struct list_head root_buses;
46 /* Lock this when doing any operations in sh_info */
47 spinlock_t sh_info_lock;
48 struct xen_pci_sharedinfo *sh_info;
49 struct work_struct op_work;
56 struct pcifront_device *pdev;
59 static inline struct pcifront_device *
60 pcifront_get_pdev(struct pcifront_sd *sd)
65 static inline void pcifront_init_sd(struct pcifront_sd *sd,
66 unsigned int domain, unsigned int bus,
67 struct pcifront_device *pdev)
73 static DEFINE_SPINLOCK(pcifront_dev_lock);
74 static struct pcifront_device *pcifront_dev;
76 static int verbose_request;
77 module_param(verbose_request, int, 0644);
79 static int errno_to_pcibios_err(int errno)
82 case XEN_PCI_ERR_success:
83 return PCIBIOS_SUCCESSFUL;
85 case XEN_PCI_ERR_dev_not_found:
86 return PCIBIOS_DEVICE_NOT_FOUND;
88 case XEN_PCI_ERR_invalid_offset:
89 case XEN_PCI_ERR_op_failed:
90 return PCIBIOS_BAD_REGISTER_NUMBER;
92 case XEN_PCI_ERR_not_implemented:
93 return PCIBIOS_FUNC_NOT_SUPPORTED;
95 case XEN_PCI_ERR_access_denied:
96 return PCIBIOS_SET_FAILED;
101 static inline void schedule_pcifront_aer_op(struct pcifront_device *pdev)
103 if (test_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags)
104 && !test_and_set_bit(_PDEVB_op_active, &pdev->flags)) {
105 dev_dbg(&pdev->xdev->dev, "schedule aer frontend job\n");
106 schedule_work(&pdev->op_work);
110 static int do_pci_op(struct pcifront_device *pdev, struct xen_pci_op *op)
113 struct xen_pci_op *active_op = &pdev->sh_info->op;
114 unsigned long irq_flags;
115 evtchn_port_t port = pdev->evtchn;
116 unsigned irq = pdev->irq;
120 spin_lock_irqsave(&pdev->sh_info_lock, irq_flags);
122 memcpy(active_op, op, sizeof(struct xen_pci_op));
126 set_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags);
127 notify_remote_via_evtchn(port);
130 * We set a poll timeout of 3 seconds but give up on return after
131 * 2 seconds. It is better to time out too late rather than too early
132 * (in the latter case we end up continually re-executing poll() with a
133 * timeout in the past). 1s difference gives plenty of slack for error.
135 do_gettimeofday(&tv);
136 ns_timeout = timeval_to_ns(&tv) + 2 * (s64)NSEC_PER_SEC;
138 xen_clear_irq_pending(irq);
140 while (test_bit(_XEN_PCIF_active,
141 (unsigned long *)&pdev->sh_info->flags)) {
142 xen_poll_irq_timeout(irq, jiffies + 3*HZ);
143 xen_clear_irq_pending(irq);
144 do_gettimeofday(&tv);
145 ns = timeval_to_ns(&tv);
146 if (ns > ns_timeout) {
147 dev_err(&pdev->xdev->dev,
148 "pciback not responding!!!\n");
149 clear_bit(_XEN_PCIF_active,
150 (unsigned long *)&pdev->sh_info->flags);
151 err = XEN_PCI_ERR_dev_not_found;
157 * We might lose backend service request since we
158 * reuse same evtchn with pci_conf backend response. So re-schedule
159 * aer pcifront service.
161 if (test_bit(_XEN_PCIB_active,
162 (unsigned long *)&pdev->sh_info->flags)) {
163 dev_err(&pdev->xdev->dev,
164 "schedule aer pcifront service\n");
165 schedule_pcifront_aer_op(pdev);
168 memcpy(op, active_op, sizeof(struct xen_pci_op));
172 spin_unlock_irqrestore(&pdev->sh_info_lock, irq_flags);
176 /* Access to this function is spinlocked in drivers/pci/access.c */
177 static int pcifront_bus_read(struct pci_bus *bus, unsigned int devfn,
178 int where, int size, u32 *val)
181 struct xen_pci_op op = {
182 .cmd = XEN_PCI_OP_conf_read,
183 .domain = pci_domain_nr(bus),
189 struct pcifront_sd *sd = bus->sysdata;
190 struct pcifront_device *pdev = pcifront_get_pdev(sd);
193 dev_info(&pdev->xdev->dev,
194 "read dev=%04x:%02x:%02x.%d - offset %x size %d\n",
195 pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),
196 PCI_FUNC(devfn), where, size);
198 err = do_pci_op(pdev, &op);
202 dev_info(&pdev->xdev->dev, "read got back value %x\n",
206 } else if (err == -ENODEV) {
207 /* No device here, pretend that it just returned 0 */
212 return errno_to_pcibios_err(err);
215 /* Access to this function is spinlocked in drivers/pci/access.c */
216 static int pcifront_bus_write(struct pci_bus *bus, unsigned int devfn,
217 int where, int size, u32 val)
219 struct xen_pci_op op = {
220 .cmd = XEN_PCI_OP_conf_write,
221 .domain = pci_domain_nr(bus),
228 struct pcifront_sd *sd = bus->sysdata;
229 struct pcifront_device *pdev = pcifront_get_pdev(sd);
232 dev_info(&pdev->xdev->dev,
233 "write dev=%04x:%02x:%02x.%d - "
234 "offset %x size %d val %x\n",
235 pci_domain_nr(bus), bus->number,
236 PCI_SLOT(devfn), PCI_FUNC(devfn), where, size, val);
238 return errno_to_pcibios_err(do_pci_op(pdev, &op));
241 static struct pci_ops pcifront_bus_ops = {
242 .read = pcifront_bus_read,
243 .write = pcifront_bus_write,
246 #ifdef CONFIG_PCI_MSI
247 static int pci_frontend_enable_msix(struct pci_dev *dev,
248 int vector[], int nvec)
252 struct xen_pci_op op = {
253 .cmd = XEN_PCI_OP_enable_msix,
254 .domain = pci_domain_nr(dev->bus),
255 .bus = dev->bus->number,
259 struct pcifront_sd *sd = dev->bus->sysdata;
260 struct pcifront_device *pdev = pcifront_get_pdev(sd);
261 struct msi_desc *entry;
263 if (nvec > SH_INFO_MAX_VEC) {
264 dev_err(&dev->dev, "too much vector for pci frontend: %x."
265 " Increase SH_INFO_MAX_VEC.\n", nvec);
270 list_for_each_entry(entry, &dev->msi_list, list) {
271 op.msix_entries[i].entry = entry->msi_attrib.entry_nr;
272 /* Vector is useless at this point. */
273 op.msix_entries[i].vector = -1;
277 err = do_pci_op(pdev, &op);
280 if (likely(!op.value)) {
281 /* we get the result */
282 for (i = 0; i < nvec; i++) {
283 if (op.msix_entries[i].vector <= 0) {
284 dev_warn(&dev->dev, "MSI-X entry %d is invalid: %d!\n",
285 i, op.msix_entries[i].vector);
290 vector[i] = op.msix_entries[i].vector;
293 printk(KERN_DEBUG "enable msix get value %x\n",
298 dev_err(&dev->dev, "enable msix get err %x\n", err);
303 static void pci_frontend_disable_msix(struct pci_dev *dev)
306 struct xen_pci_op op = {
307 .cmd = XEN_PCI_OP_disable_msix,
308 .domain = pci_domain_nr(dev->bus),
309 .bus = dev->bus->number,
312 struct pcifront_sd *sd = dev->bus->sysdata;
313 struct pcifront_device *pdev = pcifront_get_pdev(sd);
315 err = do_pci_op(pdev, &op);
317 /* What should do for error ? */
319 dev_err(&dev->dev, "pci_disable_msix get err %x\n", err);
322 static int pci_frontend_enable_msi(struct pci_dev *dev, int vector[])
325 struct xen_pci_op op = {
326 .cmd = XEN_PCI_OP_enable_msi,
327 .domain = pci_domain_nr(dev->bus),
328 .bus = dev->bus->number,
331 struct pcifront_sd *sd = dev->bus->sysdata;
332 struct pcifront_device *pdev = pcifront_get_pdev(sd);
334 err = do_pci_op(pdev, &op);
336 vector[0] = op.value;
338 dev_warn(&dev->dev, "MSI entry is invalid: %d!\n",
344 dev_err(&dev->dev, "pci frontend enable msi failed for dev "
345 "%x:%x\n", op.bus, op.devfn);
351 static void pci_frontend_disable_msi(struct pci_dev *dev)
354 struct xen_pci_op op = {
355 .cmd = XEN_PCI_OP_disable_msi,
356 .domain = pci_domain_nr(dev->bus),
357 .bus = dev->bus->number,
360 struct pcifront_sd *sd = dev->bus->sysdata;
361 struct pcifront_device *pdev = pcifront_get_pdev(sd);
363 err = do_pci_op(pdev, &op);
364 if (err == XEN_PCI_ERR_dev_not_found) {
365 /* XXX No response from backend, what shall we do? */
366 printk(KERN_DEBUG "get no response from backend for disable MSI\n");
370 /* how can pciback notify us fail? */
371 printk(KERN_DEBUG "get fake response frombackend\n");
374 static struct xen_pci_frontend_ops pci_frontend_ops = {
375 .enable_msi = pci_frontend_enable_msi,
376 .disable_msi = pci_frontend_disable_msi,
377 .enable_msix = pci_frontend_enable_msix,
378 .disable_msix = pci_frontend_disable_msix,
381 static void pci_frontend_registrar(int enable)
384 xen_pci_frontend = &pci_frontend_ops;
386 xen_pci_frontend = NULL;
389 static inline void pci_frontend_registrar(int enable) { };
390 #endif /* CONFIG_PCI_MSI */
392 /* Claim resources for the PCI frontend as-is, backend won't allow changes */
393 static int pcifront_claim_resource(struct pci_dev *dev, void *data)
395 struct pcifront_device *pdev = data;
399 for (i = 0; i < PCI_NUM_RESOURCES; i++) {
400 r = &dev->resource[i];
402 if (!r->parent && r->start && r->flags) {
403 dev_info(&pdev->xdev->dev, "claiming resource %s/%d\n",
405 if (pci_claim_resource(dev, i)) {
406 dev_err(&pdev->xdev->dev, "Could not claim resource %s/%d! "
407 "Device offline. Try using e820_host=1 in the guest config.\n",
416 static int pcifront_scan_bus(struct pcifront_device *pdev,
417 unsigned int domain, unsigned int bus,
423 /* Scan the bus for functions and add.
424 * We omit handling of PCI bridge attachment because pciback prevents
425 * bridges from being exported.
427 for (devfn = 0; devfn < 0x100; devfn++) {
428 d = pci_get_slot(b, devfn);
430 /* Device is already known. */
435 d = pci_scan_single_device(b, devfn);
437 dev_info(&pdev->xdev->dev, "New device on "
438 "%04x:%02x:%02x.%d found.\n", domain, bus,
439 PCI_SLOT(devfn), PCI_FUNC(devfn));
445 static int pcifront_scan_root(struct pcifront_device *pdev,
446 unsigned int domain, unsigned int bus)
449 struct pcifront_sd *sd = NULL;
450 struct pci_bus_entry *bus_entry = NULL;
453 #ifndef CONFIG_PCI_DOMAINS
455 dev_err(&pdev->xdev->dev,
456 "PCI Root in non-zero PCI Domain! domain=%d\n", domain);
457 dev_err(&pdev->xdev->dev,
458 "Please compile with CONFIG_PCI_DOMAINS\n");
464 dev_info(&pdev->xdev->dev, "Creating PCI Frontend Bus %04x:%02x\n",
467 bus_entry = kmalloc(sizeof(*bus_entry), GFP_KERNEL);
468 sd = kmalloc(sizeof(*sd), GFP_KERNEL);
469 if (!bus_entry || !sd) {
473 pcifront_init_sd(sd, domain, bus, pdev);
475 pci_lock_rescan_remove();
477 b = pci_scan_bus_parented(&pdev->xdev->dev, bus,
478 &pcifront_bus_ops, sd);
480 dev_err(&pdev->xdev->dev,
481 "Error creating PCI Frontend Bus!\n");
483 pci_unlock_rescan_remove();
489 list_add(&bus_entry->list, &pdev->root_buses);
491 /* pci_scan_bus_parented skips devices which do not have a have
492 * devfn==0. The pcifront_scan_bus enumerates all devfn. */
493 err = pcifront_scan_bus(pdev, domain, bus, b);
495 /* Claim resources before going "live" with our devices */
496 pci_walk_bus(b, pcifront_claim_resource, pdev);
498 /* Create SysFS and notify udev of the devices. Aka: "going live" */
499 pci_bus_add_devices(b);
501 pci_unlock_rescan_remove();
511 static int pcifront_rescan_root(struct pcifront_device *pdev,
512 unsigned int domain, unsigned int bus)
517 #ifndef CONFIG_PCI_DOMAINS
519 dev_err(&pdev->xdev->dev,
520 "PCI Root in non-zero PCI Domain! domain=%d\n", domain);
521 dev_err(&pdev->xdev->dev,
522 "Please compile with CONFIG_PCI_DOMAINS\n");
527 dev_info(&pdev->xdev->dev, "Rescanning PCI Frontend Bus %04x:%02x\n",
530 b = pci_find_bus(domain, bus);
532 /* If the bus is unknown, create it. */
533 return pcifront_scan_root(pdev, domain, bus);
535 err = pcifront_scan_bus(pdev, domain, bus, b);
537 /* Claim resources before going "live" with our devices */
538 pci_walk_bus(b, pcifront_claim_resource, pdev);
540 /* Create SysFS and notify udev of the devices. Aka: "going live" */
541 pci_bus_add_devices(b);
546 static void free_root_bus_devs(struct pci_bus *bus)
550 while (!list_empty(&bus->devices)) {
551 dev = container_of(bus->devices.next, struct pci_dev,
553 dev_dbg(&dev->dev, "removing device\n");
554 pci_stop_and_remove_bus_device(dev);
558 static void pcifront_free_roots(struct pcifront_device *pdev)
560 struct pci_bus_entry *bus_entry, *t;
562 dev_dbg(&pdev->xdev->dev, "cleaning up root buses\n");
564 pci_lock_rescan_remove();
565 list_for_each_entry_safe(bus_entry, t, &pdev->root_buses, list) {
566 list_del(&bus_entry->list);
568 free_root_bus_devs(bus_entry->bus);
570 kfree(bus_entry->bus->sysdata);
572 device_unregister(bus_entry->bus->bridge);
573 pci_remove_bus(bus_entry->bus);
577 pci_unlock_rescan_remove();
580 static pci_ers_result_t pcifront_common_process(int cmd,
581 struct pcifront_device *pdev,
582 pci_channel_state_t state)
584 pci_ers_result_t result;
585 struct pci_driver *pdrv;
586 int bus = pdev->sh_info->aer_op.bus;
587 int devfn = pdev->sh_info->aer_op.devfn;
588 struct pci_dev *pcidev;
591 dev_dbg(&pdev->xdev->dev,
592 "pcifront AER process: cmd %x (bus:%x, devfn%x)",
594 result = PCI_ERS_RESULT_NONE;
596 pcidev = pci_get_bus_and_slot(bus, devfn);
597 if (!pcidev || !pcidev->driver) {
598 dev_err(&pdev->xdev->dev, "device or AER driver is NULL\n");
602 pdrv = pcidev->driver;
605 if (pdrv->err_handler && pdrv->err_handler->error_detected) {
606 dev_dbg(&pcidev->dev,
607 "trying to call AER service\n");
611 case XEN_PCI_OP_aer_detected:
612 result = pdrv->err_handler->
613 error_detected(pcidev, state);
615 case XEN_PCI_OP_aer_mmio:
616 result = pdrv->err_handler->
617 mmio_enabled(pcidev);
619 case XEN_PCI_OP_aer_slotreset:
620 result = pdrv->err_handler->
623 case XEN_PCI_OP_aer_resume:
624 pdrv->err_handler->resume(pcidev);
627 dev_err(&pdev->xdev->dev,
628 "bad request in aer recovery "
636 result = PCI_ERS_RESULT_NONE;
642 static void pcifront_do_aer(struct work_struct *data)
644 struct pcifront_device *pdev =
645 container_of(data, struct pcifront_device, op_work);
646 int cmd = pdev->sh_info->aer_op.cmd;
647 pci_channel_state_t state =
648 (pci_channel_state_t)pdev->sh_info->aer_op.err;
650 /*If a pci_conf op is in progress,
651 we have to wait until it is done before service aer op*/
652 dev_dbg(&pdev->xdev->dev,
653 "pcifront service aer bus %x devfn %x\n",
654 pdev->sh_info->aer_op.bus, pdev->sh_info->aer_op.devfn);
656 pdev->sh_info->aer_op.err = pcifront_common_process(cmd, pdev, state);
658 /* Post the operation to the guest. */
660 clear_bit(_XEN_PCIB_active, (unsigned long *)&pdev->sh_info->flags);
661 notify_remote_via_evtchn(pdev->evtchn);
663 /*in case of we lost an aer request in four lines time_window*/
664 smp_mb__before_atomic();
665 clear_bit(_PDEVB_op_active, &pdev->flags);
666 smp_mb__after_atomic();
668 schedule_pcifront_aer_op(pdev);
672 static irqreturn_t pcifront_handler_aer(int irq, void *dev)
674 struct pcifront_device *pdev = dev;
675 schedule_pcifront_aer_op(pdev);
678 static int pcifront_connect_and_init_dma(struct pcifront_device *pdev)
682 spin_lock(&pcifront_dev_lock);
685 dev_info(&pdev->xdev->dev, "Installing PCI frontend\n");
690 spin_unlock(&pcifront_dev_lock);
692 if (!err && !swiotlb_nr_tbl()) {
693 err = pci_xen_swiotlb_init_late();
695 dev_err(&pdev->xdev->dev, "Could not setup SWIOTLB!\n");
700 static void pcifront_disconnect(struct pcifront_device *pdev)
702 spin_lock(&pcifront_dev_lock);
704 if (pdev == pcifront_dev) {
705 dev_info(&pdev->xdev->dev,
706 "Disconnecting PCI Frontend Buses\n");
710 spin_unlock(&pcifront_dev_lock);
712 static struct pcifront_device *alloc_pdev(struct xenbus_device *xdev)
714 struct pcifront_device *pdev;
716 pdev = kzalloc(sizeof(struct pcifront_device), GFP_KERNEL);
721 (struct xen_pci_sharedinfo *)__get_free_page(GFP_KERNEL);
722 if (pdev->sh_info == NULL) {
727 pdev->sh_info->flags = 0;
729 /*Flag for registering PV AER handler*/
730 set_bit(_XEN_PCIB_AERHANDLER, (void *)&pdev->sh_info->flags);
732 dev_set_drvdata(&xdev->dev, pdev);
735 INIT_LIST_HEAD(&pdev->root_buses);
737 spin_lock_init(&pdev->sh_info_lock);
739 pdev->evtchn = INVALID_EVTCHN;
740 pdev->gnt_ref = INVALID_GRANT_REF;
743 INIT_WORK(&pdev->op_work, pcifront_do_aer);
745 dev_dbg(&xdev->dev, "Allocated pdev @ 0x%p pdev->sh_info @ 0x%p\n",
746 pdev, pdev->sh_info);
751 static void free_pdev(struct pcifront_device *pdev)
753 dev_dbg(&pdev->xdev->dev, "freeing pdev @ 0x%p\n", pdev);
755 pcifront_free_roots(pdev);
757 cancel_work_sync(&pdev->op_work);
760 unbind_from_irqhandler(pdev->irq, pdev);
762 if (pdev->evtchn != INVALID_EVTCHN)
763 xenbus_free_evtchn(pdev->xdev, pdev->evtchn);
765 if (pdev->gnt_ref != INVALID_GRANT_REF)
766 gnttab_end_foreign_access(pdev->gnt_ref, 0 /* r/w page */,
767 (unsigned long)pdev->sh_info);
769 free_page((unsigned long)pdev->sh_info);
771 dev_set_drvdata(&pdev->xdev->dev, NULL);
776 static int pcifront_publish_info(struct pcifront_device *pdev)
779 struct xenbus_transaction trans;
782 err = xenbus_grant_ring(pdev->xdev, pdev->sh_info, 1, &gref);
786 pdev->gnt_ref = gref;
788 err = xenbus_alloc_evtchn(pdev->xdev, &pdev->evtchn);
792 err = bind_evtchn_to_irqhandler(pdev->evtchn, pcifront_handler_aer,
793 0, "pcifront", pdev);
801 err = xenbus_transaction_start(&trans);
803 xenbus_dev_fatal(pdev->xdev, err,
804 "Error writing configuration for backend "
805 "(start transaction)");
809 err = xenbus_printf(trans, pdev->xdev->nodename,
810 "pci-op-ref", "%u", pdev->gnt_ref);
812 err = xenbus_printf(trans, pdev->xdev->nodename,
813 "event-channel", "%u", pdev->evtchn);
815 err = xenbus_printf(trans, pdev->xdev->nodename,
816 "magic", XEN_PCI_MAGIC);
819 xenbus_transaction_end(trans, 1);
820 xenbus_dev_fatal(pdev->xdev, err,
821 "Error writing configuration for backend");
824 err = xenbus_transaction_end(trans, 0);
828 xenbus_dev_fatal(pdev->xdev, err,
829 "Error completing transaction "
835 xenbus_switch_state(pdev->xdev, XenbusStateInitialised);
837 dev_dbg(&pdev->xdev->dev, "publishing successful!\n");
843 static int pcifront_try_connect(struct pcifront_device *pdev)
846 int i, num_roots, len;
848 unsigned int domain, bus;
851 /* Only connect once */
852 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
853 XenbusStateInitialised)
856 err = pcifront_connect_and_init_dma(pdev);
857 if (err && err != -EEXIST) {
858 xenbus_dev_fatal(pdev->xdev, err,
859 "Error setting up PCI Frontend");
863 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
864 "root_num", "%d", &num_roots);
865 if (err == -ENOENT) {
866 xenbus_dev_error(pdev->xdev, err,
867 "No PCI Roots found, trying 0000:00");
868 err = pcifront_scan_root(pdev, 0, 0);
870 xenbus_dev_fatal(pdev->xdev, err,
871 "Error scanning PCI root 0000:00");
875 } else if (err != 1) {
878 xenbus_dev_fatal(pdev->xdev, err,
879 "Error reading number of PCI roots");
883 for (i = 0; i < num_roots; i++) {
884 len = snprintf(str, sizeof(str), "root-%d", i);
885 if (unlikely(len >= (sizeof(str) - 1))) {
890 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
891 "%x:%x", &domain, &bus);
895 xenbus_dev_fatal(pdev->xdev, err,
896 "Error reading PCI root %d", i);
900 err = pcifront_scan_root(pdev, domain, bus);
902 xenbus_dev_fatal(pdev->xdev, err,
903 "Error scanning PCI root %04x:%02x",
909 err = xenbus_switch_state(pdev->xdev, XenbusStateConnected);
915 static int pcifront_try_disconnect(struct pcifront_device *pdev)
918 enum xenbus_state prev_state;
921 prev_state = xenbus_read_driver_state(pdev->xdev->nodename);
923 if (prev_state >= XenbusStateClosing)
926 if (prev_state == XenbusStateConnected) {
927 pcifront_free_roots(pdev);
928 pcifront_disconnect(pdev);
931 err = xenbus_switch_state(pdev->xdev, XenbusStateClosed);
938 static int pcifront_attach_devices(struct pcifront_device *pdev)
941 int i, num_roots, len;
942 unsigned int domain, bus;
945 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
946 XenbusStateReconfiguring)
949 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
950 "root_num", "%d", &num_roots);
951 if (err == -ENOENT) {
952 xenbus_dev_error(pdev->xdev, err,
953 "No PCI Roots found, trying 0000:00");
954 err = pcifront_rescan_root(pdev, 0, 0);
956 xenbus_dev_fatal(pdev->xdev, err,
957 "Error scanning PCI root 0000:00");
961 } else if (err != 1) {
964 xenbus_dev_fatal(pdev->xdev, err,
965 "Error reading number of PCI roots");
969 for (i = 0; i < num_roots; i++) {
970 len = snprintf(str, sizeof(str), "root-%d", i);
971 if (unlikely(len >= (sizeof(str) - 1))) {
976 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
977 "%x:%x", &domain, &bus);
981 xenbus_dev_fatal(pdev->xdev, err,
982 "Error reading PCI root %d", i);
986 err = pcifront_rescan_root(pdev, domain, bus);
988 xenbus_dev_fatal(pdev->xdev, err,
989 "Error scanning PCI root %04x:%02x",
995 xenbus_switch_state(pdev->xdev, XenbusStateConnected);
1001 static int pcifront_detach_devices(struct pcifront_device *pdev)
1005 unsigned int domain, bus, slot, func;
1006 struct pci_dev *pci_dev;
1009 if (xenbus_read_driver_state(pdev->xdev->nodename) !=
1010 XenbusStateConnected)
1013 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, "num_devs", "%d",
1018 xenbus_dev_fatal(pdev->xdev, err,
1019 "Error reading number of PCI devices");
1023 /* Find devices being detached and remove them. */
1024 for (i = 0; i < num_devs; i++) {
1026 l = snprintf(str, sizeof(str), "state-%d", i);
1027 if (unlikely(l >= (sizeof(str) - 1))) {
1031 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str, "%d",
1034 state = XenbusStateUnknown;
1036 if (state != XenbusStateClosing)
1039 /* Remove device. */
1040 l = snprintf(str, sizeof(str), "vdev-%d", i);
1041 if (unlikely(l >= (sizeof(str) - 1))) {
1045 err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
1046 "%x:%x:%x.%x", &domain, &bus, &slot, &func);
1050 xenbus_dev_fatal(pdev->xdev, err,
1051 "Error reading PCI device %d", i);
1055 pci_dev = pci_get_domain_bus_and_slot(domain, bus,
1056 PCI_DEVFN(slot, func));
1058 dev_dbg(&pdev->xdev->dev,
1059 "Cannot get PCI device %04x:%02x:%02x.%d\n",
1060 domain, bus, slot, func);
1063 pci_lock_rescan_remove();
1064 pci_stop_and_remove_bus_device(pci_dev);
1065 pci_dev_put(pci_dev);
1066 pci_unlock_rescan_remove();
1068 dev_dbg(&pdev->xdev->dev,
1069 "PCI device %04x:%02x:%02x.%d removed.\n",
1070 domain, bus, slot, func);
1073 err = xenbus_switch_state(pdev->xdev, XenbusStateReconfiguring);
1079 static void __init_refok pcifront_backend_changed(struct xenbus_device *xdev,
1080 enum xenbus_state be_state)
1082 struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev);
1085 case XenbusStateUnknown:
1086 case XenbusStateInitialising:
1087 case XenbusStateInitWait:
1088 case XenbusStateInitialised:
1091 case XenbusStateConnected:
1092 pcifront_try_connect(pdev);
1095 case XenbusStateClosed:
1096 if (xdev->state == XenbusStateClosed)
1098 /* Missed the backend's CLOSING state -- fallthrough */
1099 case XenbusStateClosing:
1100 dev_warn(&xdev->dev, "backend going away!\n");
1101 pcifront_try_disconnect(pdev);
1104 case XenbusStateReconfiguring:
1105 pcifront_detach_devices(pdev);
1108 case XenbusStateReconfigured:
1109 pcifront_attach_devices(pdev);
1114 static int pcifront_xenbus_probe(struct xenbus_device *xdev,
1115 const struct xenbus_device_id *id)
1118 struct pcifront_device *pdev = alloc_pdev(xdev);
1122 xenbus_dev_fatal(xdev, err,
1123 "Error allocating pcifront_device struct");
1127 err = pcifront_publish_info(pdev);
1135 static int pcifront_xenbus_remove(struct xenbus_device *xdev)
1137 struct pcifront_device *pdev = dev_get_drvdata(&xdev->dev);
1144 static const struct xenbus_device_id xenpci_ids[] = {
1149 static struct xenbus_driver xenpci_driver = {
1152 .probe = pcifront_xenbus_probe,
1153 .remove = pcifront_xenbus_remove,
1154 .otherend_changed = pcifront_backend_changed,
1157 static int __init pcifront_init(void)
1159 if (!xen_pv_domain() || xen_initial_domain())
1162 if (!xen_has_pv_devices())
1165 pci_frontend_registrar(1 /* enable */);
1167 return xenbus_register_frontend(&xenpci_driver);
1170 static void __exit pcifront_cleanup(void)
1172 xenbus_unregister_driver(&xenpci_driver);
1173 pci_frontend_registrar(0 /* disable */);
1175 module_init(pcifront_init);
1176 module_exit(pcifront_cleanup);
1178 MODULE_DESCRIPTION("Xen PCI passthrough frontend.");
1179 MODULE_LICENSE("GPL");
1180 MODULE_ALIAS("xen:pci");