pc: acpi-build: generate pvpanic device description dynamically
[qemu/qmp-unstable.git] / hw / misc / ivshmem.c
blob5d272c84e9c7d92f3c17400ab8e41cb9f1622bba
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 "hw/hw.h"
20 #include "hw/i386/pc.h"
21 #include "hw/pci/pci.h"
22 #include "hw/pci/msix.h"
23 #include "sysemu/kvm.h"
24 #include "migration/migration.h"
25 #include "qapi/qmp/qerror.h"
26 #include "qemu/event_notifier.h"
27 #include "qemu/fifo8.h"
28 #include "sysemu/char.h"
30 #include <sys/mman.h>
31 #include <sys/types.h>
32 #include <limits.h>
34 #define PCI_VENDOR_ID_IVSHMEM PCI_VENDOR_ID_REDHAT_QUMRANET
35 #define PCI_DEVICE_ID_IVSHMEM 0x1110
37 #define IVSHMEM_IOEVENTFD 0
38 #define IVSHMEM_MSI 1
40 #define IVSHMEM_PEER 0
41 #define IVSHMEM_MASTER 1
43 #define IVSHMEM_REG_BAR_SIZE 0x100
45 //#define DEBUG_IVSHMEM
46 #ifdef DEBUG_IVSHMEM
47 #define IVSHMEM_DPRINTF(fmt, ...) \
48 do {printf("IVSHMEM: " fmt, ## __VA_ARGS__); } while (0)
49 #else
50 #define IVSHMEM_DPRINTF(fmt, ...)
51 #endif
53 #define TYPE_IVSHMEM "ivshmem"
54 #define IVSHMEM(obj) \
55 OBJECT_CHECK(IVShmemState, (obj), TYPE_IVSHMEM)
57 typedef struct Peer {
58 int nb_eventfds;
59 EventNotifier *eventfds;
60 } Peer;
62 typedef struct EventfdEntry {
63 PCIDevice *pdev;
64 int vector;
65 } EventfdEntry;
67 typedef struct IVShmemState {
68 /*< private >*/
69 PCIDevice parent_obj;
70 /*< public >*/
72 uint32_t intrmask;
73 uint32_t intrstatus;
74 uint32_t doorbell;
76 CharDriverState **eventfd_chr;
77 CharDriverState *server_chr;
78 Fifo8 incoming_fifo;
79 MemoryRegion ivshmem_mmio;
81 /* We might need to register the BAR before we actually have the memory.
82 * So prepare a container MemoryRegion for the BAR immediately and
83 * add a subregion when we have the memory.
85 MemoryRegion bar;
86 MemoryRegion ivshmem;
87 uint64_t ivshmem_size; /* size of shared memory region */
88 uint32_t ivshmem_attr;
89 uint32_t ivshmem_64bit;
90 int shm_fd; /* shared memory file descriptor */
92 Peer *peers;
93 int nb_peers; /* how many guests we have space for */
94 int max_peer; /* maximum numbered peer */
96 int vm_id;
97 uint32_t vectors;
98 uint32_t features;
99 EventfdEntry *eventfd_table;
101 Error *migration_blocker;
103 char * shmobj;
104 char * sizearg;
105 char * role;
106 int role_val; /* scalar to avoid multiple string comparisons */
107 } IVShmemState;
109 /* registers for the Inter-VM shared memory device */
110 enum ivshmem_registers {
111 INTRMASK = 0,
112 INTRSTATUS = 4,
113 IVPOSITION = 8,
114 DOORBELL = 12,
117 static inline uint32_t ivshmem_has_feature(IVShmemState *ivs,
118 unsigned int feature) {
119 return (ivs->features & (1 << feature));
122 static inline bool is_power_of_two(uint64_t x) {
123 return (x & (x - 1)) == 0;
126 /* accessing registers - based on rtl8139 */
127 static void ivshmem_update_irq(IVShmemState *s, int val)
129 PCIDevice *d = PCI_DEVICE(s);
130 int isr;
131 isr = (s->intrstatus & s->intrmask) & 0xffffffff;
133 /* don't print ISR resets */
134 if (isr) {
135 IVSHMEM_DPRINTF("Set IRQ to %d (%04x %04x)\n",
136 isr ? 1 : 0, s->intrstatus, s->intrmask);
139 pci_set_irq(d, (isr != 0));
142 static void ivshmem_IntrMask_write(IVShmemState *s, uint32_t val)
144 IVSHMEM_DPRINTF("IntrMask write(w) val = 0x%04x\n", val);
146 s->intrmask = val;
148 ivshmem_update_irq(s, val);
151 static uint32_t ivshmem_IntrMask_read(IVShmemState *s)
153 uint32_t ret = s->intrmask;
155 IVSHMEM_DPRINTF("intrmask read(w) val = 0x%04x\n", ret);
157 return ret;
160 static void ivshmem_IntrStatus_write(IVShmemState *s, uint32_t val)
162 IVSHMEM_DPRINTF("IntrStatus write(w) val = 0x%04x\n", val);
164 s->intrstatus = val;
166 ivshmem_update_irq(s, val);
169 static uint32_t ivshmem_IntrStatus_read(IVShmemState *s)
171 uint32_t ret = s->intrstatus;
173 /* reading ISR clears all interrupts */
174 s->intrstatus = 0;
176 ivshmem_update_irq(s, 0);
178 return ret;
181 static void ivshmem_io_write(void *opaque, hwaddr addr,
182 uint64_t val, unsigned size)
184 IVShmemState *s = opaque;
186 uint16_t dest = val >> 16;
187 uint16_t vector = val & 0xff;
189 addr &= 0xfc;
191 IVSHMEM_DPRINTF("writing to addr " TARGET_FMT_plx "\n", addr);
192 switch (addr)
194 case INTRMASK:
195 ivshmem_IntrMask_write(s, val);
196 break;
198 case INTRSTATUS:
199 ivshmem_IntrStatus_write(s, val);
200 break;
202 case DOORBELL:
203 /* check that dest VM ID is reasonable */
204 if (dest > s->max_peer) {
205 IVSHMEM_DPRINTF("Invalid destination VM ID (%d)\n", dest);
206 break;
209 /* check doorbell range */
210 if (vector < s->peers[dest].nb_eventfds) {
211 IVSHMEM_DPRINTF("Notifying VM %d on vector %d\n", dest, vector);
212 event_notifier_set(&s->peers[dest].eventfds[vector]);
214 break;
215 default:
216 IVSHMEM_DPRINTF("Invalid VM Doorbell VM %d\n", dest);
220 static uint64_t ivshmem_io_read(void *opaque, hwaddr addr,
221 unsigned size)
224 IVShmemState *s = opaque;
225 uint32_t ret;
227 switch (addr)
229 case INTRMASK:
230 ret = ivshmem_IntrMask_read(s);
231 break;
233 case INTRSTATUS:
234 ret = ivshmem_IntrStatus_read(s);
235 break;
237 case IVPOSITION:
238 /* return my VM ID if the memory is mapped */
239 if (s->shm_fd > 0) {
240 ret = s->vm_id;
241 } else {
242 ret = -1;
244 break;
246 default:
247 IVSHMEM_DPRINTF("why are we reading " TARGET_FMT_plx "\n", addr);
248 ret = 0;
251 return ret;
254 static const MemoryRegionOps ivshmem_mmio_ops = {
255 .read = ivshmem_io_read,
256 .write = ivshmem_io_write,
257 .endianness = DEVICE_NATIVE_ENDIAN,
258 .impl = {
259 .min_access_size = 4,
260 .max_access_size = 4,
264 static void ivshmem_receive(void *opaque, const uint8_t *buf, int size)
266 IVShmemState *s = opaque;
268 ivshmem_IntrStatus_write(s, *buf);
270 IVSHMEM_DPRINTF("ivshmem_receive 0x%02x\n", *buf);
273 static int ivshmem_can_receive(void * opaque)
275 return 8;
278 static void ivshmem_event(void *opaque, int event)
280 IVSHMEM_DPRINTF("ivshmem_event %d\n", event);
283 static void fake_irqfd(void *opaque, const uint8_t *buf, int size) {
285 EventfdEntry *entry = opaque;
286 PCIDevice *pdev = entry->pdev;
288 IVSHMEM_DPRINTF("interrupt on vector %p %d\n", pdev, entry->vector);
289 msix_notify(pdev, entry->vector);
292 static CharDriverState* create_eventfd_chr_device(void * opaque, EventNotifier *n,
293 int vector)
295 /* create a event character device based on the passed eventfd */
296 IVShmemState *s = opaque;
297 CharDriverState * chr;
298 int eventfd = event_notifier_get_fd(n);
300 chr = qemu_chr_open_eventfd(eventfd);
302 if (chr == NULL) {
303 error_report("creating eventfd for eventfd %d failed", eventfd);
304 exit(1);
306 qemu_chr_fe_claim_no_fail(chr);
308 /* if MSI is supported we need multiple interrupts */
309 if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
310 s->eventfd_table[vector].pdev = PCI_DEVICE(s);
311 s->eventfd_table[vector].vector = vector;
313 qemu_chr_add_handlers(chr, ivshmem_can_receive, fake_irqfd,
314 ivshmem_event, &s->eventfd_table[vector]);
315 } else {
316 qemu_chr_add_handlers(chr, ivshmem_can_receive, ivshmem_receive,
317 ivshmem_event, s);
320 return chr;
324 static int check_shm_size(IVShmemState *s, int fd) {
325 /* check that the guest isn't going to try and map more memory than the
326 * the object has allocated return -1 to indicate error */
328 struct stat buf;
330 if (fstat(fd, &buf) < 0) {
331 error_report("exiting: fstat on fd %d failed: %s",
332 fd, strerror(errno));
333 return -1;
336 if (s->ivshmem_size > buf.st_size) {
337 error_report("Requested memory size greater"
338 " than shared object size (%" PRIu64 " > %" PRIu64")",
339 s->ivshmem_size, (uint64_t)buf.st_size);
340 return -1;
341 } else {
342 return 0;
346 /* create the shared memory BAR when we are not using the server, so we can
347 * create the BAR and map the memory immediately */
348 static void create_shared_memory_BAR(IVShmemState *s, int fd) {
350 void * ptr;
352 s->shm_fd = fd;
354 ptr = mmap(0, s->ivshmem_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
356 memory_region_init_ram_ptr(&s->ivshmem, OBJECT(s), "ivshmem.bar2",
357 s->ivshmem_size, ptr);
358 vmstate_register_ram(&s->ivshmem, DEVICE(s));
359 memory_region_add_subregion(&s->bar, 0, &s->ivshmem);
361 /* region for shared memory */
362 pci_register_bar(PCI_DEVICE(s), 2, s->ivshmem_attr, &s->bar);
365 static void ivshmem_add_eventfd(IVShmemState *s, int posn, int i)
367 memory_region_add_eventfd(&s->ivshmem_mmio,
368 DOORBELL,
370 true,
371 (posn << 16) | i,
372 &s->peers[posn].eventfds[i]);
375 static void ivshmem_del_eventfd(IVShmemState *s, int posn, int i)
377 memory_region_del_eventfd(&s->ivshmem_mmio,
378 DOORBELL,
380 true,
381 (posn << 16) | i,
382 &s->peers[posn].eventfds[i]);
385 static void close_guest_eventfds(IVShmemState *s, int posn)
387 int i, guest_curr_max;
389 if (!ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) {
390 return;
392 if (posn < 0 || posn >= s->nb_peers) {
393 return;
396 guest_curr_max = s->peers[posn].nb_eventfds;
398 memory_region_transaction_begin();
399 for (i = 0; i < guest_curr_max; i++) {
400 ivshmem_del_eventfd(s, posn, i);
402 memory_region_transaction_commit();
403 for (i = 0; i < guest_curr_max; i++) {
404 event_notifier_cleanup(&s->peers[posn].eventfds[i]);
407 g_free(s->peers[posn].eventfds);
408 s->peers[posn].nb_eventfds = 0;
411 /* this function increase the dynamic storage need to store data about other
412 * guests */
413 static int increase_dynamic_storage(IVShmemState *s, int new_min_size)
416 int j, old_nb_alloc;
418 /* check for integer overflow */
419 if (new_min_size >= INT_MAX / sizeof(Peer) - 1 || new_min_size <= 0) {
420 return -1;
423 old_nb_alloc = s->nb_peers;
425 if (new_min_size >= s->nb_peers) {
426 /* +1 because #new_min_size is used as last array index */
427 s->nb_peers = new_min_size + 1;
428 } else {
429 return 0;
432 IVSHMEM_DPRINTF("bumping storage to %d guests\n", s->nb_peers);
433 s->peers = g_realloc(s->peers, s->nb_peers * sizeof(Peer));
435 /* zero out new pointers */
436 for (j = old_nb_alloc; j < s->nb_peers; j++) {
437 s->peers[j].eventfds = NULL;
438 s->peers[j].nb_eventfds = 0;
441 return 0;
444 static void ivshmem_read(void *opaque, const uint8_t *buf, int size)
446 IVShmemState *s = opaque;
447 int incoming_fd, tmp_fd;
448 int guest_max_eventfd;
449 long incoming_posn;
451 if (fifo8_is_empty(&s->incoming_fifo) && size == sizeof(incoming_posn)) {
452 memcpy(&incoming_posn, buf, size);
453 } else {
454 const uint8_t *p;
455 uint32_t num;
457 IVSHMEM_DPRINTF("short read of %d bytes\n", size);
458 num = MAX(size, sizeof(long) - fifo8_num_used(&s->incoming_fifo));
459 fifo8_push_all(&s->incoming_fifo, buf, num);
460 if (fifo8_num_used(&s->incoming_fifo) < sizeof(incoming_posn)) {
461 return;
463 size -= num;
464 buf += num;
465 p = fifo8_pop_buf(&s->incoming_fifo, sizeof(incoming_posn), &num);
466 g_assert(num == sizeof(incoming_posn));
467 memcpy(&incoming_posn, p, sizeof(incoming_posn));
468 if (size > 0) {
469 fifo8_push_all(&s->incoming_fifo, buf, size);
473 if (incoming_posn < -1) {
474 IVSHMEM_DPRINTF("invalid incoming_posn %ld\n", incoming_posn);
475 return;
478 /* pick off s->server_chr->msgfd and store it, posn should accompany msg */
479 tmp_fd = qemu_chr_fe_get_msgfd(s->server_chr);
480 IVSHMEM_DPRINTF("posn is %ld, fd is %d\n", incoming_posn, tmp_fd);
482 /* make sure we have enough space for this guest */
483 if (incoming_posn >= s->nb_peers) {
484 if (increase_dynamic_storage(s, incoming_posn) < 0) {
485 error_report("increase_dynamic_storage() failed");
486 if (tmp_fd != -1) {
487 close(tmp_fd);
489 return;
493 if (tmp_fd == -1) {
494 /* if posn is positive and unseen before then this is our posn*/
495 if ((incoming_posn >= 0) &&
496 (s->peers[incoming_posn].eventfds == NULL)) {
497 /* receive our posn */
498 s->vm_id = incoming_posn;
499 return;
500 } else {
501 /* otherwise an fd == -1 means an existing guest has gone away */
502 IVSHMEM_DPRINTF("posn %ld has gone away\n", incoming_posn);
503 close_guest_eventfds(s, incoming_posn);
504 return;
508 /* because of the implementation of get_msgfd, we need a dup */
509 incoming_fd = dup(tmp_fd);
511 if (incoming_fd == -1) {
512 error_report("could not allocate file descriptor %s", strerror(errno));
513 close(tmp_fd);
514 return;
517 /* if the position is -1, then it's shared memory region fd */
518 if (incoming_posn == -1) {
520 void * map_ptr;
522 s->max_peer = 0;
524 if (check_shm_size(s, incoming_fd) == -1) {
525 exit(1);
528 /* mmap the region and map into the BAR2 */
529 map_ptr = mmap(0, s->ivshmem_size, PROT_READ|PROT_WRITE, MAP_SHARED,
530 incoming_fd, 0);
531 memory_region_init_ram_ptr(&s->ivshmem, OBJECT(s),
532 "ivshmem.bar2", s->ivshmem_size, map_ptr);
533 vmstate_register_ram(&s->ivshmem, DEVICE(s));
535 IVSHMEM_DPRINTF("guest h/w addr = %p, size = %" PRIu64 "\n",
536 map_ptr, s->ivshmem_size);
538 memory_region_add_subregion(&s->bar, 0, &s->ivshmem);
540 /* only store the fd if it is successfully mapped */
541 s->shm_fd = incoming_fd;
543 return;
546 /* each guest has an array of eventfds, and we keep track of how many
547 * guests for each VM */
548 guest_max_eventfd = s->peers[incoming_posn].nb_eventfds;
550 if (guest_max_eventfd == 0) {
551 /* one eventfd per MSI vector */
552 s->peers[incoming_posn].eventfds = g_new(EventNotifier, s->vectors);
555 /* this is an eventfd for a particular guest VM */
556 IVSHMEM_DPRINTF("eventfds[%ld][%d] = %d\n", incoming_posn,
557 guest_max_eventfd, incoming_fd);
558 event_notifier_init_fd(&s->peers[incoming_posn].eventfds[guest_max_eventfd],
559 incoming_fd);
561 /* increment count for particular guest */
562 s->peers[incoming_posn].nb_eventfds++;
564 /* keep track of the maximum VM ID */
565 if (incoming_posn > s->max_peer) {
566 s->max_peer = incoming_posn;
569 if (incoming_posn == s->vm_id) {
570 s->eventfd_chr[guest_max_eventfd] = create_eventfd_chr_device(s,
571 &s->peers[s->vm_id].eventfds[guest_max_eventfd],
572 guest_max_eventfd);
575 if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD)) {
576 ivshmem_add_eventfd(s, incoming_posn, guest_max_eventfd);
580 /* Select the MSI-X vectors used by device.
581 * ivshmem maps events to vectors statically, so
582 * we just enable all vectors on init and after reset. */
583 static void ivshmem_use_msix(IVShmemState * s)
585 PCIDevice *d = PCI_DEVICE(s);
586 int i;
588 if (!msix_present(d)) {
589 return;
592 for (i = 0; i < s->vectors; i++) {
593 msix_vector_use(d, i);
597 static void ivshmem_reset(DeviceState *d)
599 IVShmemState *s = IVSHMEM(d);
601 s->intrstatus = 0;
602 ivshmem_use_msix(s);
605 static uint64_t ivshmem_get_size(IVShmemState * s) {
607 uint64_t value;
608 char *ptr;
610 value = strtoull(s->sizearg, &ptr, 10);
611 switch (*ptr) {
612 case 0: case 'M': case 'm':
613 value <<= 20;
614 break;
615 case 'G': case 'g':
616 value <<= 30;
617 break;
618 default:
619 error_report("invalid ram size: %s", s->sizearg);
620 exit(1);
623 /* BARs must be a power of 2 */
624 if (!is_power_of_two(value)) {
625 error_report("size must be power of 2");
626 exit(1);
629 return value;
632 static void ivshmem_setup_msi(IVShmemState * s)
634 if (msix_init_exclusive_bar(PCI_DEVICE(s), s->vectors, 1)) {
635 IVSHMEM_DPRINTF("msix initialization failed\n");
636 exit(1);
639 IVSHMEM_DPRINTF("msix initialized (%d vectors)\n", s->vectors);
641 /* allocate QEMU char devices for receiving interrupts */
642 s->eventfd_table = g_malloc0(s->vectors * sizeof(EventfdEntry));
644 ivshmem_use_msix(s);
647 static void ivshmem_save(QEMUFile* f, void *opaque)
649 IVShmemState *proxy = opaque;
650 PCIDevice *pci_dev = PCI_DEVICE(proxy);
652 IVSHMEM_DPRINTF("ivshmem_save\n");
653 pci_device_save(pci_dev, f);
655 if (ivshmem_has_feature(proxy, IVSHMEM_MSI)) {
656 msix_save(pci_dev, f);
657 } else {
658 qemu_put_be32(f, proxy->intrstatus);
659 qemu_put_be32(f, proxy->intrmask);
664 static int ivshmem_load(QEMUFile* f, void *opaque, int version_id)
666 IVSHMEM_DPRINTF("ivshmem_load\n");
668 IVShmemState *proxy = opaque;
669 PCIDevice *pci_dev = PCI_DEVICE(proxy);
670 int ret;
672 if (version_id > 0) {
673 return -EINVAL;
676 if (proxy->role_val == IVSHMEM_PEER) {
677 error_report("'peer' devices are not migratable");
678 return -EINVAL;
681 ret = pci_device_load(pci_dev, f);
682 if (ret) {
683 return ret;
686 if (ivshmem_has_feature(proxy, IVSHMEM_MSI)) {
687 msix_load(pci_dev, f);
688 ivshmem_use_msix(proxy);
689 } else {
690 proxy->intrstatus = qemu_get_be32(f);
691 proxy->intrmask = qemu_get_be32(f);
694 return 0;
697 static void ivshmem_write_config(PCIDevice *pci_dev, uint32_t address,
698 uint32_t val, int len)
700 pci_default_write_config(pci_dev, address, val, len);
701 msix_write_config(pci_dev, address, val, len);
704 static int pci_ivshmem_init(PCIDevice *dev)
706 IVShmemState *s = IVSHMEM(dev);
707 uint8_t *pci_conf;
709 if (s->sizearg == NULL)
710 s->ivshmem_size = 4 << 20; /* 4 MB default */
711 else {
712 s->ivshmem_size = ivshmem_get_size(s);
715 fifo8_create(&s->incoming_fifo, sizeof(long));
717 register_savevm(DEVICE(dev), "ivshmem", 0, 0, ivshmem_save, ivshmem_load,
718 dev);
720 /* IRQFD requires MSI */
721 if (ivshmem_has_feature(s, IVSHMEM_IOEVENTFD) &&
722 !ivshmem_has_feature(s, IVSHMEM_MSI)) {
723 error_report("ioeventfd/irqfd requires MSI");
724 exit(1);
727 /* check that role is reasonable */
728 if (s->role) {
729 if (strncmp(s->role, "peer", 5) == 0) {
730 s->role_val = IVSHMEM_PEER;
731 } else if (strncmp(s->role, "master", 7) == 0) {
732 s->role_val = IVSHMEM_MASTER;
733 } else {
734 error_report("'role' must be 'peer' or 'master'");
735 exit(1);
737 } else {
738 s->role_val = IVSHMEM_MASTER; /* default */
741 if (s->role_val == IVSHMEM_PEER) {
742 error_setg(&s->migration_blocker,
743 "Migration is disabled when using feature 'peer mode' in device 'ivshmem'");
744 migrate_add_blocker(s->migration_blocker);
747 pci_conf = dev->config;
748 pci_conf[PCI_COMMAND] = PCI_COMMAND_IO | PCI_COMMAND_MEMORY;
750 pci_config_set_interrupt_pin(pci_conf, 1);
752 s->shm_fd = 0;
754 memory_region_init_io(&s->ivshmem_mmio, OBJECT(s), &ivshmem_mmio_ops, s,
755 "ivshmem-mmio", IVSHMEM_REG_BAR_SIZE);
757 /* region for registers*/
758 pci_register_bar(dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY,
759 &s->ivshmem_mmio);
761 memory_region_init(&s->bar, OBJECT(s), "ivshmem-bar2-container", s->ivshmem_size);
762 s->ivshmem_attr = PCI_BASE_ADDRESS_SPACE_MEMORY |
763 PCI_BASE_ADDRESS_MEM_PREFETCH;
764 if (s->ivshmem_64bit) {
765 s->ivshmem_attr |= PCI_BASE_ADDRESS_MEM_TYPE_64;
768 if ((s->server_chr != NULL) &&
769 (strncmp(s->server_chr->filename, "unix:", 5) == 0)) {
770 /* if we get a UNIX socket as the parameter we will talk
771 * to the ivshmem server to receive the memory region */
773 if (s->shmobj != NULL) {
774 error_report("WARNING: do not specify both 'chardev' "
775 "and 'shm' with ivshmem");
778 IVSHMEM_DPRINTF("using shared memory server (socket = %s)\n",
779 s->server_chr->filename);
781 if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
782 ivshmem_setup_msi(s);
785 /* we allocate enough space for 16 guests and grow as needed */
786 s->nb_peers = 16;
787 s->vm_id = -1;
789 /* allocate/initialize space for interrupt handling */
790 s->peers = g_malloc0(s->nb_peers * sizeof(Peer));
792 pci_register_bar(dev, 2, s->ivshmem_attr, &s->bar);
794 s->eventfd_chr = g_malloc0(s->vectors * sizeof(CharDriverState *));
796 qemu_chr_add_handlers(s->server_chr, ivshmem_can_receive, ivshmem_read,
797 ivshmem_event, s);
798 } else {
799 /* just map the file immediately, we're not using a server */
800 int fd;
802 if (s->shmobj == NULL) {
803 error_report("Must specify 'chardev' or 'shm' to ivshmem");
804 exit(1);
807 IVSHMEM_DPRINTF("using shm_open (shm object = %s)\n", s->shmobj);
809 /* try opening with O_EXCL and if it succeeds zero the memory
810 * by truncating to 0 */
811 if ((fd = shm_open(s->shmobj, O_CREAT|O_RDWR|O_EXCL,
812 S_IRWXU|S_IRWXG|S_IRWXO)) > 0) {
813 /* truncate file to length PCI device's memory */
814 if (ftruncate(fd, s->ivshmem_size) != 0) {
815 error_report("could not truncate shared file");
818 } else if ((fd = shm_open(s->shmobj, O_CREAT|O_RDWR,
819 S_IRWXU|S_IRWXG|S_IRWXO)) < 0) {
820 error_report("could not open shared file");
821 exit(1);
825 if (check_shm_size(s, fd) == -1) {
826 exit(1);
829 create_shared_memory_BAR(s, fd);
833 dev->config_write = ivshmem_write_config;
835 return 0;
838 static void pci_ivshmem_uninit(PCIDevice *dev)
840 IVShmemState *s = IVSHMEM(dev);
842 if (s->migration_blocker) {
843 migrate_del_blocker(s->migration_blocker);
844 error_free(s->migration_blocker);
847 memory_region_del_subregion(&s->bar, &s->ivshmem);
848 vmstate_unregister_ram(&s->ivshmem, DEVICE(dev));
849 unregister_savevm(DEVICE(dev), "ivshmem", s);
850 fifo8_destroy(&s->incoming_fifo);
853 static Property ivshmem_properties[] = {
854 DEFINE_PROP_CHR("chardev", IVShmemState, server_chr),
855 DEFINE_PROP_STRING("size", IVShmemState, sizearg),
856 DEFINE_PROP_UINT32("vectors", IVShmemState, vectors, 1),
857 DEFINE_PROP_BIT("ioeventfd", IVShmemState, features, IVSHMEM_IOEVENTFD, false),
858 DEFINE_PROP_BIT("msi", IVShmemState, features, IVSHMEM_MSI, true),
859 DEFINE_PROP_STRING("shm", IVShmemState, shmobj),
860 DEFINE_PROP_STRING("role", IVShmemState, role),
861 DEFINE_PROP_UINT32("use64", IVShmemState, ivshmem_64bit, 1),
862 DEFINE_PROP_END_OF_LIST(),
865 static void ivshmem_class_init(ObjectClass *klass, void *data)
867 DeviceClass *dc = DEVICE_CLASS(klass);
868 PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
870 k->init = pci_ivshmem_init;
871 k->exit = pci_ivshmem_uninit;
872 k->vendor_id = PCI_VENDOR_ID_IVSHMEM;
873 k->device_id = PCI_DEVICE_ID_IVSHMEM;
874 k->class_id = PCI_CLASS_MEMORY_RAM;
875 dc->reset = ivshmem_reset;
876 dc->props = ivshmem_properties;
877 set_bit(DEVICE_CATEGORY_MISC, dc->categories);
880 static const TypeInfo ivshmem_info = {
881 .name = TYPE_IVSHMEM,
882 .parent = TYPE_PCI_DEVICE,
883 .instance_size = sizeof(IVShmemState),
884 .class_init = ivshmem_class_init,
887 static void ivshmem_register_types(void)
889 type_register_static(&ivshmem_info);
892 type_init(ivshmem_register_types)