qemu/hw/vfio/helpers.c
Cédric Le Goater 005b8d1045 vfio: Move vfio_get_device_info() to helpers.c
vfio_get_device_info() is a low level routine. Move it with the other
helpers.

Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: John Levon <john.levon@nutanix.com>
Link: https://lore.kernel.org/qemu-devel/20250318095415.670319-19-clg@redhat.com
Link: https://lore.kernel.org/qemu-devel/20250326075122.1299361-20-clg@redhat.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
2025-04-25 09:01:37 +02:00

492 lines
12 KiB
C

/*
* low level and IOMMU backend agnostic helpers used by VFIO devices,
* related to regions, interrupts, capabilities
*
* Copyright Red Hat, Inc. 2012
*
* Authors:
* Alex Williamson <alex.williamson@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
* Based on qemu-kvm device-assignment:
* Adapted for KVM by Qumranet.
* Copyright (c) 2007, Neocleus, Alex Novik (alex@neocleus.com)
* Copyright (c) 2007, Neocleus, Guy Zana (guy@neocleus.com)
* Copyright (C) 2008, Qumranet, Amit Shah (amit.shah@qumranet.com)
* Copyright (C) 2008, Red Hat, Amit Shah (amit.shah@redhat.com)
* Copyright (C) 2008, IBM, Muli Ben-Yehuda (muli@il.ibm.com)
*/
#include "qemu/osdep.h"
#include <sys/ioctl.h>
#include "system/kvm.h"
#include "hw/vfio/vfio-common.h"
#include "hw/vfio/pci.h"
#include "hw/hw.h"
#include "trace.h"
#include "qapi/error.h"
#include "qemu/error-report.h"
#include "qemu/units.h"
#include "monitor/monitor.h"
#include "vfio-helpers.h"
/*
* Common VFIO interrupt disable
*/
void vfio_disable_irqindex(VFIODevice *vbasedev, int index)
{
struct vfio_irq_set irq_set = {
.argsz = sizeof(irq_set),
.flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER,
.index = index,
.start = 0,
.count = 0,
};
ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
}
void vfio_unmask_single_irqindex(VFIODevice *vbasedev, int index)
{
struct vfio_irq_set irq_set = {
.argsz = sizeof(irq_set),
.flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_UNMASK,
.index = index,
.start = 0,
.count = 1,
};
ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
}
void vfio_mask_single_irqindex(VFIODevice *vbasedev, int index)
{
struct vfio_irq_set irq_set = {
.argsz = sizeof(irq_set),
.flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_MASK,
.index = index,
.start = 0,
.count = 1,
};
ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
}
static inline const char *action_to_str(int action)
{
switch (action) {
case VFIO_IRQ_SET_ACTION_MASK:
return "MASK";
case VFIO_IRQ_SET_ACTION_UNMASK:
return "UNMASK";
case VFIO_IRQ_SET_ACTION_TRIGGER:
return "TRIGGER";
default:
return "UNKNOWN ACTION";
}
}
static const char *index_to_str(VFIODevice *vbasedev, int index)
{
if (vbasedev->type != VFIO_DEVICE_TYPE_PCI) {
return NULL;
}
switch (index) {
case VFIO_PCI_INTX_IRQ_INDEX:
return "INTX";
case VFIO_PCI_MSI_IRQ_INDEX:
return "MSI";
case VFIO_PCI_MSIX_IRQ_INDEX:
return "MSIX";
case VFIO_PCI_ERR_IRQ_INDEX:
return "ERR";
case VFIO_PCI_REQ_IRQ_INDEX:
return "REQ";
default:
return NULL;
}
}
bool vfio_set_irq_signaling(VFIODevice *vbasedev, int index, int subindex,
int action, int fd, Error **errp)
{
ERRP_GUARD();
g_autofree struct vfio_irq_set *irq_set = NULL;
int argsz;
const char *name;
int32_t *pfd;
argsz = sizeof(*irq_set) + sizeof(*pfd);
irq_set = g_malloc0(argsz);
irq_set->argsz = argsz;
irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | action;
irq_set->index = index;
irq_set->start = subindex;
irq_set->count = 1;
pfd = (int32_t *)&irq_set->data;
*pfd = fd;
if (!ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, irq_set)) {
return true;
}
error_setg_errno(errp, errno, "VFIO_DEVICE_SET_IRQS failure");
name = index_to_str(vbasedev, index);
if (name) {
error_prepend(errp, "%s-%d: ", name, subindex);
} else {
error_prepend(errp, "index %d-%d: ", index, subindex);
}
error_prepend(errp,
"Failed to %s %s eventfd signaling for interrupt ",
fd < 0 ? "tear down" : "set up", action_to_str(action));
return false;
}
int vfio_bitmap_alloc(VFIOBitmap *vbmap, hwaddr size)
{
vbmap->pages = REAL_HOST_PAGE_ALIGN(size) / qemu_real_host_page_size();
vbmap->size = ROUND_UP(vbmap->pages, sizeof(__u64) * BITS_PER_BYTE) /
BITS_PER_BYTE;
vbmap->bitmap = g_try_malloc0(vbmap->size);
if (!vbmap->bitmap) {
return -ENOMEM;
}
return 0;
}
struct vfio_info_cap_header *
vfio_get_cap(void *ptr, uint32_t cap_offset, uint16_t id)
{
struct vfio_info_cap_header *hdr;
for (hdr = ptr + cap_offset; hdr != ptr; hdr = ptr + hdr->next) {
if (hdr->id == id) {
return hdr;
}
}
return NULL;
}
struct vfio_info_cap_header *
vfio_get_region_info_cap(struct vfio_region_info *info, uint16_t id)
{
if (!(info->flags & VFIO_REGION_INFO_FLAG_CAPS)) {
return NULL;
}
return vfio_get_cap((void *)info, info->cap_offset, id);
}
struct vfio_info_cap_header *
vfio_get_device_info_cap(struct vfio_device_info *info, uint16_t id)
{
if (!(info->flags & VFIO_DEVICE_FLAGS_CAPS)) {
return NULL;
}
return vfio_get_cap((void *)info, info->cap_offset, id);
}
int vfio_get_region_info(VFIODevice *vbasedev, int index,
struct vfio_region_info **info)
{
size_t argsz = sizeof(struct vfio_region_info);
*info = g_malloc0(argsz);
(*info)->index = index;
retry:
(*info)->argsz = argsz;
if (ioctl(vbasedev->fd, VFIO_DEVICE_GET_REGION_INFO, *info)) {
g_free(*info);
*info = NULL;
return -errno;
}
if ((*info)->argsz > argsz) {
argsz = (*info)->argsz;
*info = g_realloc(*info, argsz);
goto retry;
}
return 0;
}
struct vfio_info_cap_header *
vfio_get_iommu_type1_info_cap(struct vfio_iommu_type1_info *info, uint16_t id)
{
if (!(info->flags & VFIO_IOMMU_INFO_CAPS)) {
return NULL;
}
return vfio_get_cap((void *)info, info->cap_offset, id);
}
bool vfio_get_info_dma_avail(struct vfio_iommu_type1_info *info,
unsigned int *avail)
{
struct vfio_info_cap_header *hdr;
struct vfio_iommu_type1_info_dma_avail *cap;
/* If the capability cannot be found, assume no DMA limiting */
hdr = vfio_get_iommu_type1_info_cap(info,
VFIO_IOMMU_TYPE1_INFO_DMA_AVAIL);
if (!hdr) {
return false;
}
if (avail != NULL) {
cap = (void *) hdr;
*avail = cap->avail;
}
return true;
}
int vfio_kvm_device_add_fd(int fd, Error **errp)
{
#ifdef CONFIG_KVM
struct kvm_device_attr attr = {
.group = KVM_DEV_VFIO_FILE,
.attr = KVM_DEV_VFIO_FILE_ADD,
.addr = (uint64_t)(unsigned long)&fd,
};
if (!kvm_enabled()) {
return 0;
}
if (vfio_kvm_device_fd < 0) {
struct kvm_create_device cd = {
.type = KVM_DEV_TYPE_VFIO,
};
if (kvm_vm_ioctl(kvm_state, KVM_CREATE_DEVICE, &cd)) {
error_setg_errno(errp, errno, "Failed to create KVM VFIO device");
return -errno;
}
vfio_kvm_device_fd = cd.fd;
}
if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
error_setg_errno(errp, errno, "Failed to add fd %d to KVM VFIO device",
fd);
return -errno;
}
#endif
return 0;
}
int vfio_kvm_device_del_fd(int fd, Error **errp)
{
#ifdef CONFIG_KVM
struct kvm_device_attr attr = {
.group = KVM_DEV_VFIO_FILE,
.attr = KVM_DEV_VFIO_FILE_DEL,
.addr = (uint64_t)(unsigned long)&fd,
};
if (vfio_kvm_device_fd < 0) {
error_setg(errp, "KVM VFIO device isn't created yet");
return -EINVAL;
}
if (ioctl(vfio_kvm_device_fd, KVM_SET_DEVICE_ATTR, &attr)) {
error_setg_errno(errp, errno,
"Failed to remove fd %d from KVM VFIO device", fd);
return -errno;
}
#endif
return 0;
}
struct vfio_device_info *vfio_get_device_info(int fd)
{
struct vfio_device_info *info;
uint32_t argsz = sizeof(*info);
info = g_malloc0(argsz);
retry:
info->argsz = argsz;
if (ioctl(fd, VFIO_DEVICE_GET_INFO, info)) {
g_free(info);
return NULL;
}
if (info->argsz > argsz) {
argsz = info->argsz;
info = g_realloc(info, argsz);
goto retry;
}
return info;
}
int vfio_get_dev_region_info(VFIODevice *vbasedev, uint32_t type,
uint32_t subtype, struct vfio_region_info **info)
{
int i;
for (i = 0; i < vbasedev->num_regions; i++) {
struct vfio_info_cap_header *hdr;
struct vfio_region_info_cap_type *cap_type;
if (vfio_get_region_info(vbasedev, i, info)) {
continue;
}
hdr = vfio_get_region_info_cap(*info, VFIO_REGION_INFO_CAP_TYPE);
if (!hdr) {
g_free(*info);
continue;
}
cap_type = container_of(hdr, struct vfio_region_info_cap_type, header);
trace_vfio_get_dev_region(vbasedev->name, i,
cap_type->type, cap_type->subtype);
if (cap_type->type == type && cap_type->subtype == subtype) {
return 0;
}
g_free(*info);
}
*info = NULL;
return -ENODEV;
}
bool vfio_has_region_cap(VFIODevice *vbasedev, int region, uint16_t cap_type)
{
g_autofree struct vfio_region_info *info = NULL;
bool ret = false;
if (!vfio_get_region_info(vbasedev, region, &info)) {
if (vfio_get_region_info_cap(info, cap_type)) {
ret = true;
}
}
return ret;
}
bool vfio_device_get_name(VFIODevice *vbasedev, Error **errp)
{
ERRP_GUARD();
struct stat st;
if (vbasedev->fd < 0) {
if (stat(vbasedev->sysfsdev, &st) < 0) {
error_setg_errno(errp, errno, "no such host device");
error_prepend(errp, VFIO_MSG_PREFIX, vbasedev->sysfsdev);
return false;
}
/* User may specify a name, e.g: VFIO platform device */
if (!vbasedev->name) {
vbasedev->name = g_path_get_basename(vbasedev->sysfsdev);
}
} else {
if (!vbasedev->iommufd) {
error_setg(errp, "Use FD passing only with iommufd backend");
return false;
}
/*
* Give a name with fd so any function printing out vbasedev->name
* will not break.
*/
if (!vbasedev->name) {
vbasedev->name = g_strdup_printf("VFIO_FD%d", vbasedev->fd);
}
}
return true;
}
void vfio_device_set_fd(VFIODevice *vbasedev, const char *str, Error **errp)
{
ERRP_GUARD();
int fd = monitor_fd_param(monitor_cur(), str, errp);
if (fd < 0) {
error_prepend(errp, "Could not parse remote object fd %s:", str);
return;
}
vbasedev->fd = fd;
}
void vfio_device_init(VFIODevice *vbasedev, int type, VFIODeviceOps *ops,
DeviceState *dev, bool ram_discard)
{
vbasedev->type = type;
vbasedev->ops = ops;
vbasedev->dev = dev;
vbasedev->fd = -1;
vbasedev->ram_block_discard_allowed = ram_discard;
}
int vfio_device_get_aw_bits(VFIODevice *vdev)
{
/*
* iova_ranges is a sorted list. For old kernels that support
* VFIO but not support query of iova ranges, iova_ranges is NULL,
* in this case HOST_IOMMU_DEVICE_CAP_AW_BITS_MAX(64) is returned.
*/
GList *l = g_list_last(vdev->bcontainer->iova_ranges);
if (l) {
Range *range = l->data;
return range_get_last_bit(range) + 1;
}
return HOST_IOMMU_DEVICE_CAP_AW_BITS_MAX;
}
bool vfio_device_is_mdev(VFIODevice *vbasedev)
{
g_autofree char *subsys = NULL;
g_autofree char *tmp = NULL;
if (!vbasedev->sysfsdev) {
return false;
}
tmp = g_strdup_printf("%s/subsystem", vbasedev->sysfsdev);
subsys = realpath(tmp, NULL);
return subsys && (strcmp(subsys, "/sys/bus/mdev") == 0);
}
bool vfio_device_hiod_realize(VFIODevice *vbasedev, Error **errp)
{
HostIOMMUDevice *hiod = vbasedev->hiod;
if (!hiod) {
return true;
}
return HOST_IOMMU_DEVICE_GET_CLASS(hiod)->realize(hiod, vbasedev, errp);
}
VFIODevice *vfio_get_vfio_device(Object *obj)
{
if (object_dynamic_cast(obj, TYPE_VFIO_PCI)) {
return &VFIO_PCI(obj)->vbasedev;
} else {
return NULL;
}
}