util: move declarations out of qemu-common.h
[qemu/ar7.git] / hw / misc / ivshmem.c
blob30ba1be957d57a285bc131dbec822f346671633e
1 /*
2 * Inter-VM Shared Memory PCI device.
4 * Author:
5 * Cam Macdonell <cam@cs.ualberta.ca>
7 * Based On: cirrus_vga.c
8 * Copyright (c) 2004 Fabrice Bellard
9 * Copyright (c) 2004 Makoto Suzuki (suzu)
11 * and rtl8139.c
12 * Copyright (c) 2006 Igor Kovalenko
14 * This code is licensed under the GNU GPL v2.
16 * Contributions after 2012-01-13 are licensed under the terms of the
17 * GNU GPL, version 2 or (at your option) any later version.
19 #include "qemu/osdep.h"
20 #include "qapi/error.h"
21 #include "qemu/cutils.h"
22 #include "hw/hw.h"
23 #include "hw/i386/pc.h"
24 #include "hw/pci/pci.h"
25 #include "hw/pci/msi.h"
26 #include "hw/pci/msix.h"
27 #include "sysemu/kvm.h"
28 #include "migration/migration.h"
29 #include "qemu/error-report.h"
30 #include "qemu/event_notifier.h"
31 #include "qemu/fifo8.h"
32 #include "sysemu/char.h"
33 #include "sysemu/hostmem.h"
34 #include "qapi/visitor.h"
35 #include "exec/ram_addr.h"
37 #include "hw/misc/ivshmem.h"
39 #include <sys/mman.h>
41 #define PCI_VENDOR_ID_IVSHMEM PCI_VENDOR_ID_REDHAT_QUMRANET
42 #define PCI_DEVICE_ID_IVSHMEM 0x1110
44 #define IVSHMEM_MAX_PEERS G_MAXUINT16
45 #define IVSHMEM_IOEVENTFD 0
46 #define IVSHMEM_MSI 1
48 #define IVSHMEM_PEER 0
49 #define IVSHMEM_MASTER 1
51 #define IVSHMEM_REG_BAR_SIZE 0x100
53 //#define DEBUG_IVSHMEM
54 #ifdef DEBUG_IVSHMEM
55 #define IVSHMEM_DPRINTF(fmt, ...) \
56 do {printf("IVSHMEM: " fmt, ## __VA_ARGS__); } while (0)
57 #else
58 #define IVSHMEM_DPRINTF(fmt, ...)
59 #endif
61 #define TYPE_IVSHMEM "ivshmem"
62 #define IVSHMEM(obj) \
63 OBJECT_CHECK(IVShmemState, (obj), TYPE_IVSHMEM)
65 typedef struct Peer {
66 int nb_eventfds;
67 EventNotifier *eventfds;
68 } Peer;
70 typedef struct MSIVector {
71 PCIDevice *pdev;
72 int virq;
73 } MSIVector;
75 typedef struct IVShmemState {
76 /*< private >*/
77 PCIDevice parent_obj;
78 /*< public >*/
80 HostMemoryBackend *hostmem;
81 uint32_t intrmask;
82 uint32_t intrstatus;
84 CharDriverState **eventfd_chr;
85 CharDriverState *server_chr;
86 Fifo8 incoming_fifo;
87 MemoryRegion ivshmem_mmio;
89 /* We might need to register the BAR before we actually have the memory.
90 * So prepare a container MemoryRegion for the BAR immediately and
91 * add a subregion when we have the memory.
93 MemoryRegion bar;
94 MemoryRegion ivshmem;
95 uint64_t ivshmem_size; /* size of shared memory region */
96 uint32_t ivshmem_64bit;
98 Peer *peers;
99 int nb_peers; /* how many peers we have space for */
101 int vm_id;
102 uint32_t vectors;
103 uint32_t features;
104 MSIVector *msi_vectors;
106 Error *migration_blocker;
108 char * shmobj;
109 char * sizearg;
110 char * role;
111 int role_val; /* scalar to avoid multiple string comparisons */
112 } IVShmemState;
114 /* registers for the Inter-VM shared memory device */
115 enum ivshmem_registers {
116 INTRMASK = 0,
117 INTRSTATUS = 4,
118 IVPOSITION = 8,
119 DOORBELL = 12,
122 static inline uint32_t ivshmem_has_feature(IVShmemState *ivs,
123 unsigned int feature) {
124 return (ivs->features & (1 << feature));
127 /* accessing registers - based on rtl8139 */
128 static void ivshmem_update_irq(IVShmemState *s)
130 PCIDevice *d = PCI_DEVICE(s);
131 int isr;
132 isr = (s->intrstatus & s->intrmask) & 0xffffffff;
134 /* don't print ISR resets */
135 if (isr) {
136 IVSHMEM_DPRINTF("Set IRQ to %d (%04x %04x)\n",
137 isr ? 1 : 0, s->intrstatus, s->intrmask);
140 pci_set_irq(d, (isr != 0));
143 static void ivshmem_IntrMask_write(IVShmemState *s, uint32_t val)
145 IVSHMEM_DPRINTF("IntrMask write(w) val = 0x%04x\n", val);
147 s->intrmask = val;
149 ivshmem_update_irq(s);
152 static uint32_t ivshmem_IntrMask_read(IVShmemState *s)
154 uint32_t ret = s->intrmask;
156 IVSHMEM_DPRINTF("intrmask read(w) val = 0x%04x\n", ret);
158 return ret;
161 static void ivshmem_IntrStatus_write(IVShmemState *s, uint32_t val)
163 IVSHMEM_DPRINTF("IntrStatus write(w) val = 0x%04x\n", val);
165 s->intrstatus = val;
167 ivshmem_update_irq(s);
170 static uint32_t ivshmem_IntrStatus_read(IVShmemState *s)
172 uint32_t ret = s->intrstatus;
174 /* reading ISR clears all interrupts */
175 s->intrstatus = 0;
177 ivshmem_update_irq(s);
179 return ret;
182 static void ivshmem_io_write(void *opaque, hwaddr addr,
183 uint64_t val, unsigned size)
185 IVShmemState *s = opaque;
187 uint16_t dest = val >> 16;
188 uint16_t vector = val & 0xff;
190 addr &= 0xfc;
192 IVSHMEM_DPRINTF("writing to addr " TARGET_FMT_plx "\n", addr);
193 switch (addr)
195 case INTRMASK:
196 ivshmem_IntrMask_write(s, val);
197 break;
199 case INTRSTATUS:
200 ivshmem_IntrStatus_write(s, val);
201 break;
203 case DOORBELL:
204 /* check that dest VM ID is reasonable */
205 if (dest >= s->nb_peers) {
206 IVSHMEM_DPRINTF("Invalid destination VM ID (%d)\n", dest);
207 break;
210 /* check doorbell range */
211 if (vector < s->peers[dest].nb_eventfds) {
212 IVSHMEM_DPRINTF("Notifying VM %d on vector %d\n", dest, vector);
213 event_notifier_set(&s->peers[dest].eventfds[vector]);
214 } else {
215 IVSHMEM_DPRINTF("Invalid destination vector %d on VM %d\n",
216 vector, dest);
218 break;
219 default:
220 IVSHMEM_DPRINTF("Unhandled write " TARGET_FMT_plx "\n", addr);
224 static uint64_t ivshmem_io_read(void *opaque, hwaddr addr,
225 unsigned size)
228 IVShmemState *s = opaque;
229 uint32_t ret;
231 switch (addr)
233 case INTRMASK:
234 ret = ivshmem_IntrMask_read(s);
235 break;
237 case INTRSTATUS:
238 ret = ivshmem_IntrStatus_read(s);
239 break;
241 case IVPOSITION:
242 /* return my VM ID if the memory is mapped */
243 if (memory_region_is_mapped(&s->ivshmem)) {
244 ret = s->vm_id;
245 } else {
246 ret = -1;
248 break;
250 default:
251 IVSHMEM_DPRINTF("why are we reading " TARGET_FMT_plx "\n", addr);
252 ret = 0;
255 return ret;
258 static const MemoryRegionOps ivshmem_mmio_ops = {
259 .read = ivshmem_io_read,
260 .write = ivshmem_io_write,
261 .endianness = DEVICE_NATIVE_ENDIAN,
262 .impl = {
263 .min_access_size = 4,
264 .max_access_size = 4,
268 static int ivshmem_can_receive(void * opaque)
270 return sizeof(int64_t);
273 static void ivshmem_event(void *opaque, int event)
275 IVSHMEM_DPRINTF("ivshmem_event %d\n", event);
278 static void ivshmem_vector_notify(void *opaque)
280 MSIVector *entry = opaque;
281 PCIDevice *pdev = entry->pdev;
282 IVShmemState *s = IVSHMEM(pdev);
283 int vector = entry - s->msi_vectors;
284 EventNotifier *n = &s->peers[s->vm_id].eventfds[vector];
286 if (!event_notifier_test_and_clear(n)) {
287 return;
290 IVSHMEM_DPRINTF("interrupt on vector %p %d\n", pdev, vector);
291 if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
292 msix_notify(pdev, vector);
293 } else {
294 ivshmem_IntrStatus_write(s, 1);
298 static int ivshmem_vector_unmask(PCIDevice *dev, unsigned vector,
299 MSIMessage msg)
301 IVShmemState *s = IVSHMEM(dev);
302 EventNotifier *n = &s->peers[s->vm_id].eventfds[vector];
303 MSIVector *v = &s->msi_vectors[vector];
304 int ret;
306 IVSHMEM_DPRINTF("vector unmask %p %d\n", dev, vector);
308 ret = kvm_irqchip_update_msi_route(kvm_state, v->virq, msg, dev);
309 if (ret < 0) {
310 return ret;
313 return kvm_irqchip_add_irqfd_notifier_gsi(kvm_state, n, NULL, v->virq);
316 static void ivshmem_vector_mask(PCIDevice *dev, unsigned vector)
318 IVShmemState *s = IVSHMEM(dev);
319 EventNotifier *n = &s->peers[s->vm_id].eventfds[vector];
320 int ret;
322 IVSHMEM_DPRINTF("vector mask %p %d\n", dev, vector);
324 ret = kvm_irqchip_remove_irqfd_notifier_gsi(kvm_state, n,
325 s->msi_vectors[vector].virq);
326 if (ret != 0) {
327 error_report("remove_irqfd_notifier_gsi failed");
331 static void ivshmem_vector_poll(PCIDevice *dev,
332 unsigned int vector_start,
333 unsigned int vector_end)
335 IVShmemState *s = IVSHMEM(dev);
336 unsigned int vector;
338 IVSHMEM_DPRINTF("vector poll %p %d-%d\n", dev, vector_start, vector_end);
340 vector_end = MIN(vector_end, s->vectors);
342 for (vector = vector_start; vector < vector_end; vector++) {
343 EventNotifier *notifier = &s->peers[s->vm_id].eventfds[vector];
345 if (!msix_is_masked(dev, vector)) {
346 continue;
349 if (event_notifier_test_and_clear(notifier)) {
350 msix_set_pending(dev, vector);
355 static void watch_vector_notifier(IVShmemState *s, EventNotifier *n,
356 int vector)
358 int eventfd = event_notifier_get_fd(n);
360 /* if MSI is supported we need multiple interrupts */
361 s->msi_vectors[vector].pdev = PCI_DEVICE(s);
363 qemu_set_fd_handler(eventfd, ivshmem_vector_notify,
364 NULL, &s->msi_vectors[vector]);
367 static int check_shm_size(IVShmemState *s, int fd, Error **errp)
369 /* check that the guest isn't going to try and map more memory than the
370 * the object has allocated return -1 to indicate error */
372 struct stat buf;
374 if (fstat(fd, &buf) < 0) {
375 error_setg(errp, "exiting: fstat on fd %d failed: %s",
376 fd, strerror(errno));
377 return -1;
380 if (s->ivshmem_size > buf.st_size) {
381 error_setg(errp, "Requested memory size greater"
382 " than shared object size (%" PRIu64 " > %" PRIu64")",
383 s->ivshmem_size, (uint64_t)buf.st_size);
384 return -1;
385 } else {
386 return 0;
390 /* create the shared memory BAR when we are not using the server, so we can
391 * create the BAR and map the memory immediately */
392 static int create_shared_memory_BAR(IVShmemState *s, int fd, uint8_t attr,
393 Error **errp)
395 void * ptr;
397 ptr = mmap(0, s->ivshmem_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
398 if (ptr == MAP_FAILED) {
399 error_setg_errno(errp, errno, "Failed to mmap shared memory");
400 return -1;
403 memory_region_init_ram_ptr(&s->ivshmem, OBJECT(s), "ivshmem.bar2",
404 s->ivshmem_size, ptr);
405 qemu_set_ram_fd(memory_region_get_ram_addr(&s->ivshmem), fd);
406 vmstate_register_ram(&s->ivshmem, DEVICE(s));
407 memory_region_add_subregion(&s->bar, 0, &s->ivshmem);
409 /* region for shared memory */
410 pci_register_bar(PCI_DEVICE(s), 2, attr, &s->bar);
412 return 0;
415 static void ivshmem_add_eventfd(IVShmemState *s, int posn, int i)
417 memory_region_add_eventfd(&s->ivshmem_mmio,
418 DOORBELL,
420 true,
421 (posn << 16) | i,
422 &s->peers[posn].eventfds[i]);
425 static void ivshmem_del_eventfd(IVShmemState *s, int posn, int i)
427 memory_region_del_eventfd(&s->ivshmem_mmio,
428 DOORBELL,
430 true,
431 (posn << 16) | i,
432 &s->peers[posn].eventfds[i]);
435 static void close_peer_eventfds(IVShmemState *s, int posn)
437 int i, n;
439 if (!ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) {
440 return;
442 if (posn < 0 || posn >= s->nb_peers) {
443 error_report("invalid peer %d", posn);
444 return;
447 n = s->peers[posn].nb_eventfds;
449 memory_region_transaction_begin();
450 for (i = 0; i < n; i++) {
451 ivshmem_del_eventfd(s, posn, i);
453 memory_region_transaction_commit();
454 for (i = 0; i < n; i++) {
455 event_notifier_cleanup(&s->peers[posn].eventfds[i]);
458 g_free(s->peers[posn].eventfds);
459 s->peers[posn].nb_eventfds = 0;
462 /* this function increase the dynamic storage need to store data about other
463 * peers */
464 static int resize_peers(IVShmemState *s, int new_min_size)
467 int j, old_size;
469 /* limit number of max peers */
470 if (new_min_size <= 0 || new_min_size > IVSHMEM_MAX_PEERS) {
471 return -1;
473 if (new_min_size <= s->nb_peers) {
474 return 0;
477 old_size = s->nb_peers;
478 s->nb_peers = new_min_size;
480 IVSHMEM_DPRINTF("bumping storage to %d peers\n", s->nb_peers);
482 s->peers = g_realloc(s->peers, s->nb_peers * sizeof(Peer));
484 for (j = old_size; j < s->nb_peers; j++) {
485 s->peers[j].eventfds = g_new0(EventNotifier, s->vectors);
486 s->peers[j].nb_eventfds = 0;
489 return 0;
492 static bool fifo_update_and_get(IVShmemState *s, const uint8_t *buf, int size,
493 void *data, size_t len)
495 const uint8_t *p;
496 uint32_t num;
498 assert(len <= sizeof(int64_t)); /* limitation of the fifo */
499 if (fifo8_is_empty(&s->incoming_fifo) && size == len) {
500 memcpy(data, buf, size);
501 return true;
504 IVSHMEM_DPRINTF("short read of %d bytes\n", size);
506 num = MIN(size, sizeof(int64_t) - fifo8_num_used(&s->incoming_fifo));
507 fifo8_push_all(&s->incoming_fifo, buf, num);
509 if (fifo8_num_used(&s->incoming_fifo) < len) {
510 assert(num == 0);
511 return false;
514 size -= num;
515 buf += num;
516 p = fifo8_pop_buf(&s->incoming_fifo, len, &num);
517 assert(num == len);
519 memcpy(data, p, len);
521 if (size > 0) {
522 fifo8_push_all(&s->incoming_fifo, buf, size);
525 return true;
528 static bool fifo_update_and_get_i64(IVShmemState *s,
529 const uint8_t *buf, int size, int64_t *i64)
531 if (fifo_update_and_get(s, buf, size, i64, sizeof(*i64))) {
532 *i64 = GINT64_FROM_LE(*i64);
533 return true;
536 return false;
539 static int ivshmem_add_kvm_msi_virq(IVShmemState *s, int vector)
541 PCIDevice *pdev = PCI_DEVICE(s);
542 MSIMessage msg = msix_get_message(pdev, vector);
543 int ret;
545 IVSHMEM_DPRINTF("ivshmem_add_kvm_msi_virq vector:%d\n", vector);
547 if (s->msi_vectors[vector].pdev != NULL) {
548 return 0;
551 ret = kvm_irqchip_add_msi_route(kvm_state, msg, pdev);
552 if (ret < 0) {
553 error_report("ivshmem: kvm_irqchip_add_msi_route failed");
554 return -1;
557 s->msi_vectors[vector].virq = ret;
558 s->msi_vectors[vector].pdev = pdev;
560 return 0;
563 static void setup_interrupt(IVShmemState *s, int vector)
565 EventNotifier *n = &s->peers[s->vm_id].eventfds[vector];
566 bool with_irqfd = kvm_msi_via_irqfd_enabled() &&
567 ivshmem_has_feature(s, IVSHMEM_MSI);
568 PCIDevice *pdev = PCI_DEVICE(s);
570 IVSHMEM_DPRINTF("setting up interrupt for vector: %d\n", vector);
572 if (!with_irqfd) {
573 IVSHMEM_DPRINTF("with eventfd");
574 watch_vector_notifier(s, n, vector);
575 } else if (msix_enabled(pdev)) {
576 IVSHMEM_DPRINTF("with irqfd");
577 if (ivshmem_add_kvm_msi_virq(s, vector) < 0) {
578 return;
581 if (!msix_is_masked(pdev, vector)) {
582 kvm_irqchip_add_irqfd_notifier_gsi(kvm_state, n, NULL,
583 s->msi_vectors[vector].virq);
585 } else {
586 /* it will be delayed until msix is enabled, in write_config */
587 IVSHMEM_DPRINTF("with irqfd, delayed until msix enabled");
591 static void ivshmem_read(void *opaque, const uint8_t *buf, int size)
593 IVShmemState *s = opaque;
594 int incoming_fd;
595 int new_eventfd;
596 int64_t incoming_posn;
597 Error *err = NULL;
598 Peer *peer;
600 if (!fifo_update_and_get_i64(s, buf, size, &incoming_posn)) {
601 return;
604 if (incoming_posn < -1) {
605 IVSHMEM_DPRINTF("invalid incoming_posn %" PRId64 "\n", incoming_posn);
606 return;
609 /* pick off s->server_chr->msgfd and store it, posn should accompany msg */
610 incoming_fd = qemu_chr_fe_get_msgfd(s->server_chr);
611 IVSHMEM_DPRINTF("posn is %" PRId64 ", fd is %d\n",
612 incoming_posn, incoming_fd);
614 /* make sure we have enough space for this peer */
615 if (incoming_posn >= s->nb_peers) {
616 if (resize_peers(s, incoming_posn + 1) < 0) {
617 error_report("failed to resize peers array");
618 if (incoming_fd != -1) {
619 close(incoming_fd);
621 return;
625 peer = &s->peers[incoming_posn];
627 if (incoming_fd == -1) {
628 /* if posn is positive and unseen before then this is our posn*/
629 if (incoming_posn >= 0 && s->vm_id == -1) {
630 /* receive our posn */
631 s->vm_id = incoming_posn;
632 } else {
633 /* otherwise an fd == -1 means an existing peer has gone away */
634 IVSHMEM_DPRINTF("posn %" PRId64 " has gone away\n", incoming_posn);
635 close_peer_eventfds(s, incoming_posn);
637 return;
640 /* if the position is -1, then it's shared memory region fd */
641 if (incoming_posn == -1) {
642 void * map_ptr;
644 if (memory_region_is_mapped(&s->ivshmem)) {
645 error_report("shm already initialized");
646 close(incoming_fd);
647 return;
650 if (check_shm_size(s, incoming_fd, &err) == -1) {
651 error_report_err(err);
652 close(incoming_fd);
653 return;
656 /* mmap the region and map into the BAR2 */
657 map_ptr = mmap(0, s->ivshmem_size, PROT_READ|PROT_WRITE, MAP_SHARED,
658 incoming_fd, 0);
659 if (map_ptr == MAP_FAILED) {
660 error_report("Failed to mmap shared memory %s", strerror(errno));
661 close(incoming_fd);
662 return;
664 memory_region_init_ram_ptr(&s->ivshmem, OBJECT(s),
665 "ivshmem.bar2", s->ivshmem_size, map_ptr);
666 qemu_set_ram_fd(memory_region_get_ram_addr(&s->ivshmem),
667 incoming_fd);
668 vmstate_register_ram(&s->ivshmem, DEVICE(s));
670 IVSHMEM_DPRINTF("guest h/w addr = %p, size = %" PRIu64 "\n",
671 map_ptr, s->ivshmem_size);
673 memory_region_add_subregion(&s->bar, 0, &s->ivshmem);
675 return;
678 /* each peer has an associated array of eventfds, and we keep
679 * track of how many eventfds received so far */
680 /* get a new eventfd: */
681 if (peer->nb_eventfds >= s->vectors) {
682 error_report("Too many eventfd received, device has %d vectors",
683 s->vectors);
684 close(incoming_fd);
685 return;
688 new_eventfd = peer->nb_eventfds++;
690 /* this is an eventfd for a particular peer VM */
691 IVSHMEM_DPRINTF("eventfds[%" PRId64 "][%d] = %d\n", incoming_posn,
692 new_eventfd, incoming_fd);
693 event_notifier_init_fd(&peer->eventfds[new_eventfd], incoming_fd);
694 fcntl_setfl(incoming_fd, O_NONBLOCK); /* msix/irqfd poll non block */
696 if (incoming_posn == s->vm_id) {
697 setup_interrupt(s, new_eventfd);
700 if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) {
701 ivshmem_add_eventfd(s, incoming_posn, new_eventfd);
705 static void ivshmem_check_version(void *opaque, const uint8_t * buf, int size)
707 IVShmemState *s = opaque;
708 int tmp;
709 int64_t version;
711 if (!fifo_update_and_get_i64(s, buf, size, &version)) {
712 return;
715 tmp = qemu_chr_fe_get_msgfd(s->server_chr);
716 if (tmp != -1 || version != IVSHMEM_PROTOCOL_VERSION) {
717 fprintf(stderr, "incompatible version, you are connecting to a ivshmem-"
718 "server using a different protocol please check your setup\n");
719 qemu_chr_delete(s->server_chr);
720 s->server_chr = NULL;
721 return;
724 IVSHMEM_DPRINTF("version check ok, switch to real chardev handler\n");
725 qemu_chr_add_handlers(s->server_chr, ivshmem_can_receive, ivshmem_read,
726 ivshmem_event, s);
729 /* Select the MSI-X vectors used by device.
730 * ivshmem maps events to vectors statically, so
731 * we just enable all vectors on init and after reset. */
732 static void ivshmem_use_msix(IVShmemState * s)
734 PCIDevice *d = PCI_DEVICE(s);
735 int i;
737 IVSHMEM_DPRINTF("%s, msix present: %d\n", __func__, msix_present(d));
738 if (!msix_present(d)) {
739 return;
742 for (i = 0; i < s->vectors; i++) {
743 msix_vector_use(d, i);
747 static void ivshmem_reset(DeviceState *d)
749 IVShmemState *s = IVSHMEM(d);
751 s->intrstatus = 0;
752 s->intrmask = 0;
753 ivshmem_use_msix(s);
756 static int ivshmem_setup_interrupts(IVShmemState *s)
758 /* allocate QEMU callback data for receiving interrupts */
759 s->msi_vectors = g_malloc0(s->vectors * sizeof(MSIVector));
761 if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
762 if (msix_init_exclusive_bar(PCI_DEVICE(s), s->vectors, 1)) {
763 return -1;
766 IVSHMEM_DPRINTF("msix initialized (%d vectors)\n", s->vectors);
767 ivshmem_use_msix(s);
770 return 0;
773 static void ivshmem_enable_irqfd(IVShmemState *s)
775 PCIDevice *pdev = PCI_DEVICE(s);
776 int i;
778 for (i = 0; i < s->peers[s->vm_id].nb_eventfds; i++) {
779 ivshmem_add_kvm_msi_virq(s, i);
782 if (msix_set_vector_notifiers(pdev,
783 ivshmem_vector_unmask,
784 ivshmem_vector_mask,
785 ivshmem_vector_poll)) {
786 error_report("ivshmem: msix_set_vector_notifiers failed");
790 static void ivshmem_remove_kvm_msi_virq(IVShmemState *s, int vector)
792 IVSHMEM_DPRINTF("ivshmem_remove_kvm_msi_virq vector:%d\n", vector);
794 if (s->msi_vectors[vector].pdev == NULL) {
795 return;
798 /* it was cleaned when masked in the frontend. */
799 kvm_irqchip_release_virq(kvm_state, s->msi_vectors[vector].virq);
801 s->msi_vectors[vector].pdev = NULL;
804 static void ivshmem_disable_irqfd(IVShmemState *s)
806 PCIDevice *pdev = PCI_DEVICE(s);
807 int i;
809 for (i = 0; i < s->peers[s->vm_id].nb_eventfds; i++) {
810 ivshmem_remove_kvm_msi_virq(s, i);
813 msix_unset_vector_notifiers(pdev);
816 static void ivshmem_write_config(PCIDevice *pdev, uint32_t address,
817 uint32_t val, int len)
819 IVShmemState *s = IVSHMEM(pdev);
820 int is_enabled, was_enabled = msix_enabled(pdev);
822 pci_default_write_config(pdev, address, val, len);
823 is_enabled = msix_enabled(pdev);
825 if (kvm_msi_via_irqfd_enabled() && s->vm_id != -1) {
826 if (!was_enabled && is_enabled) {
827 ivshmem_enable_irqfd(s);
828 } else if (was_enabled && !is_enabled) {
829 ivshmem_disable_irqfd(s);
834 static void pci_ivshmem_realize(PCIDevice *dev, Error **errp)
836 IVShmemState *s = IVSHMEM(dev);
837 uint8_t *pci_conf;
838 uint8_t attr = PCI_BASE_ADDRESS_SPACE_MEMORY |
839 PCI_BASE_ADDRESS_MEM_PREFETCH;
841 if (!!s->server_chr + !!s->shmobj + !!s->hostmem != 1) {
842 error_setg(errp,
843 "You must specify either 'shm', 'chardev' or 'x-memdev'");
844 return;
847 if (s->hostmem) {
848 MemoryRegion *mr;
850 if (s->sizearg) {
851 g_warning("size argument ignored with hostmem");
854 mr = host_memory_backend_get_memory(s->hostmem, errp);
855 s->ivshmem_size = memory_region_size(mr);
856 } else if (s->sizearg == NULL) {
857 s->ivshmem_size = 4 << 20; /* 4 MB default */
858 } else {
859 char *end;
860 int64_t size = qemu_strtosz(s->sizearg, &end);
861 if (size < 0 || *end != '\0' || !is_power_of_2(size)) {
862 error_setg(errp, "Invalid size %s", s->sizearg);
863 return;
865 s->ivshmem_size = size;
868 fifo8_create(&s->incoming_fifo, sizeof(int64_t));
870 /* IRQFD requires MSI */
871 if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD) &&
872 !ivshmem_has_feature(s, IVSHMEM_MSI)) {
873 error_setg(errp, "ioeventfd/irqfd requires MSI");
874 return;
877 /* check that role is reasonable */
878 if (s->role) {
879 if (strncmp(s->role, "peer", 5) == 0) {
880 s->role_val = IVSHMEM_PEER;
881 } else if (strncmp(s->role, "master", 7) == 0) {
882 s->role_val = IVSHMEM_MASTER;
883 } else {
884 error_setg(errp, "'role' must be 'peer' or 'master'");
885 return;
887 } else {
888 s->role_val = IVSHMEM_MASTER; /* default */
891 if (s->role_val == IVSHMEM_PEER) {
892 error_setg(&s->migration_blocker,
893 "Migration is disabled when using feature 'peer mode' in device 'ivshmem'");
894 migrate_add_blocker(s->migration_blocker);
897 pci_conf = dev->config;
898 pci_conf[PCI_COMMAND] = PCI_COMMAND_IO | PCI_COMMAND_MEMORY;
900 pci_config_set_interrupt_pin(pci_conf, 1);
902 memory_region_init_io(&s->ivshmem_mmio, OBJECT(s), &ivshmem_mmio_ops, s,
903 "ivshmem-mmio", IVSHMEM_REG_BAR_SIZE);
905 /* region for registers*/
906 pci_register_bar(dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY,
907 &s->ivshmem_mmio);
909 memory_region_init(&s->bar, OBJECT(s), "ivshmem-bar2-container", s->ivshmem_size);
910 if (s->ivshmem_64bit) {
911 attr |= PCI_BASE_ADDRESS_MEM_TYPE_64;
914 if (s->hostmem != NULL) {
915 MemoryRegion *mr;
917 IVSHMEM_DPRINTF("using hostmem\n");
919 mr = host_memory_backend_get_memory(MEMORY_BACKEND(s->hostmem), errp);
920 vmstate_register_ram(mr, DEVICE(s));
921 memory_region_add_subregion(&s->bar, 0, mr);
922 pci_register_bar(PCI_DEVICE(s), 2, attr, &s->bar);
923 } else if (s->server_chr != NULL) {
924 /* FIXME do not rely on what chr drivers put into filename */
925 if (strncmp(s->server_chr->filename, "unix:", 5)) {
926 error_setg(errp, "chardev is not a unix client socket");
927 return;
930 /* if we get a UNIX socket as the parameter we will talk
931 * to the ivshmem server to receive the memory region */
933 IVSHMEM_DPRINTF("using shared memory server (socket = %s)\n",
934 s->server_chr->filename);
936 if (ivshmem_setup_interrupts(s) < 0) {
937 error_setg(errp, "failed to initialize interrupts");
938 return;
941 /* we allocate enough space for 16 peers and grow as needed */
942 resize_peers(s, 16);
943 s->vm_id = -1;
945 pci_register_bar(dev, 2, attr, &s->bar);
947 s->eventfd_chr = g_malloc0(s->vectors * sizeof(CharDriverState *));
949 qemu_chr_add_handlers(s->server_chr, ivshmem_can_receive,
950 ivshmem_check_version, ivshmem_event, s);
951 } else {
952 /* just map the file immediately, we're not using a server */
953 int fd;
955 IVSHMEM_DPRINTF("using shm_open (shm object = %s)\n", s->shmobj);
957 /* try opening with O_EXCL and if it succeeds zero the memory
958 * by truncating to 0 */
959 if ((fd = shm_open(s->shmobj, O_CREAT|O_RDWR|O_EXCL,
960 S_IRWXU|S_IRWXG|S_IRWXO)) > 0) {
961 /* truncate file to length PCI device's memory */
962 if (ftruncate(fd, s->ivshmem_size) != 0) {
963 error_report("could not truncate shared file");
966 } else if ((fd = shm_open(s->shmobj, O_CREAT|O_RDWR,
967 S_IRWXU|S_IRWXG|S_IRWXO)) < 0) {
968 error_setg(errp, "could not open shared file");
969 return;
972 if (check_shm_size(s, fd, errp) == -1) {
973 return;
976 create_shared_memory_BAR(s, fd, attr, errp);
980 static void pci_ivshmem_exit(PCIDevice *dev)
982 IVShmemState *s = IVSHMEM(dev);
983 int i;
985 fifo8_destroy(&s->incoming_fifo);
987 if (s->migration_blocker) {
988 migrate_del_blocker(s->migration_blocker);
989 error_free(s->migration_blocker);
992 if (memory_region_is_mapped(&s->ivshmem)) {
993 if (!s->hostmem) {
994 void *addr = memory_region_get_ram_ptr(&s->ivshmem);
995 int fd;
997 if (munmap(addr, s->ivshmem_size) == -1) {
998 error_report("Failed to munmap shared memory %s",
999 strerror(errno));
1002 fd = qemu_get_ram_fd(memory_region_get_ram_addr(&s->ivshmem));
1003 if (fd != -1) {
1004 close(fd);
1008 vmstate_unregister_ram(&s->ivshmem, DEVICE(dev));
1009 memory_region_del_subregion(&s->bar, &s->ivshmem);
1012 if (s->eventfd_chr) {
1013 for (i = 0; i < s->vectors; i++) {
1014 if (s->eventfd_chr[i]) {
1015 qemu_chr_free(s->eventfd_chr[i]);
1018 g_free(s->eventfd_chr);
1021 if (s->peers) {
1022 for (i = 0; i < s->nb_peers; i++) {
1023 close_peer_eventfds(s, i);
1025 g_free(s->peers);
1028 if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
1029 msix_uninit_exclusive_bar(dev);
1032 g_free(s->msi_vectors);
1035 static bool test_msix(void *opaque, int version_id)
1037 IVShmemState *s = opaque;
1039 return ivshmem_has_feature(s, IVSHMEM_MSI);
1042 static bool test_no_msix(void *opaque, int version_id)
1044 return !test_msix(opaque, version_id);
1047 static int ivshmem_pre_load(void *opaque)
1049 IVShmemState *s = opaque;
1051 if (s->role_val == IVSHMEM_PEER) {
1052 error_report("'peer' devices are not migratable");
1053 return -EINVAL;
1056 return 0;
1059 static int ivshmem_post_load(void *opaque, int version_id)
1061 IVShmemState *s = opaque;
1063 if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
1064 ivshmem_use_msix(s);
1067 return 0;
1070 static int ivshmem_load_old(QEMUFile *f, void *opaque, int version_id)
1072 IVShmemState *s = opaque;
1073 PCIDevice *pdev = PCI_DEVICE(s);
1074 int ret;
1076 IVSHMEM_DPRINTF("ivshmem_load_old\n");
1078 if (version_id != 0) {
1079 return -EINVAL;
1082 if (s->role_val == IVSHMEM_PEER) {
1083 error_report("'peer' devices are not migratable");
1084 return -EINVAL;
1087 ret = pci_device_load(pdev, f);
1088 if (ret) {
1089 return ret;
1092 if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
1093 msix_load(pdev, f);
1094 ivshmem_use_msix(s);
1095 } else {
1096 s->intrstatus = qemu_get_be32(f);
1097 s->intrmask = qemu_get_be32(f);
1100 return 0;
1103 static const VMStateDescription ivshmem_vmsd = {
1104 .name = "ivshmem",
1105 .version_id = 1,
1106 .minimum_version_id = 1,
1107 .pre_load = ivshmem_pre_load,
1108 .post_load = ivshmem_post_load,
1109 .fields = (VMStateField[]) {
1110 VMSTATE_PCI_DEVICE(parent_obj, IVShmemState),
1112 VMSTATE_MSIX_TEST(parent_obj, IVShmemState, test_msix),
1113 VMSTATE_UINT32_TEST(intrstatus, IVShmemState, test_no_msix),
1114 VMSTATE_UINT32_TEST(intrmask, IVShmemState, test_no_msix),
1116 VMSTATE_END_OF_LIST()
1118 .load_state_old = ivshmem_load_old,
1119 .minimum_version_id_old = 0
1122 static Property ivshmem_properties[] = {
1123 DEFINE_PROP_CHR("chardev", IVShmemState, server_chr),
1124 DEFINE_PROP_STRING("size", IVShmemState, sizearg),
1125 DEFINE_PROP_UINT32("vectors", IVShmemState, vectors, 1),
1126 DEFINE_PROP_BIT("ioeventfd", IVShmemState, features, IVSHMEM_IOEVENTFD, false),
1127 DEFINE_PROP_BIT("msi", IVShmemState, features, IVSHMEM_MSI, true),
1128 DEFINE_PROP_STRING("shm", IVShmemState, shmobj),
1129 DEFINE_PROP_STRING("role", IVShmemState, role),
1130 DEFINE_PROP_UINT32("use64", IVShmemState, ivshmem_64bit, 1),
1131 DEFINE_PROP_END_OF_LIST(),
1134 static void ivshmem_class_init(ObjectClass *klass, void *data)
1136 DeviceClass *dc = DEVICE_CLASS(klass);
1137 PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
1139 k->realize = pci_ivshmem_realize;
1140 k->exit = pci_ivshmem_exit;
1141 k->config_write = ivshmem_write_config;
1142 k->vendor_id = PCI_VENDOR_ID_IVSHMEM;
1143 k->device_id = PCI_DEVICE_ID_IVSHMEM;
1144 k->class_id = PCI_CLASS_MEMORY_RAM;
1145 dc->reset = ivshmem_reset;
1146 dc->props = ivshmem_properties;
1147 dc->vmsd = &ivshmem_vmsd;
1148 set_bit(DEVICE_CATEGORY_MISC, dc->categories);
1149 dc->desc = "Inter-VM shared memory";
1152 static void ivshmem_check_memdev_is_busy(Object *obj, const char *name,
1153 Object *val, Error **errp)
1155 MemoryRegion *mr;
1157 mr = host_memory_backend_get_memory(MEMORY_BACKEND(val), errp);
1158 if (memory_region_is_mapped(mr)) {
1159 char *path = object_get_canonical_path_component(val);
1160 error_setg(errp, "can't use already busy memdev: %s", path);
1161 g_free(path);
1162 } else {
1163 qdev_prop_allow_set_link_before_realize(obj, name, val, errp);
1167 static void ivshmem_init(Object *obj)
1169 IVShmemState *s = IVSHMEM(obj);
1171 object_property_add_link(obj, "x-memdev", TYPE_MEMORY_BACKEND,
1172 (Object **)&s->hostmem,
1173 ivshmem_check_memdev_is_busy,
1174 OBJ_PROP_LINK_UNREF_ON_RELEASE,
1175 &error_abort);
1178 static const TypeInfo ivshmem_info = {
1179 .name = TYPE_IVSHMEM,
1180 .parent = TYPE_PCI_DEVICE,
1181 .instance_size = sizeof(IVShmemState),
1182 .instance_init = ivshmem_init,
1183 .class_init = ivshmem_class_init,
1186 static void ivshmem_register_types(void)
1188 type_register_static(&ivshmem_info);
1191 type_init(ivshmem_register_types)