vfio: Implement a common device info helper

A common helper implementing the realloc algorithm for handling
capabilities.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Robin Voetter <robin@streamhpc.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
master
Alex Williamson 2023-06-01 08:45:06 -06:00 committed by Cédric Le Goater
parent 745c42912a
commit 634f38f0f7
3 changed files with 41 additions and 43 deletions

View File

@ -289,38 +289,11 @@ static void s390_pci_read_pfip(S390PCIBusDevice *pbdev,
memcpy(pbdev->zpci_fn.pfip, cap->pfip, CLP_PFIP_NR_SEGMENTS);
}
static struct vfio_device_info *get_device_info(S390PCIBusDevice *pbdev,
uint32_t argsz)
static struct vfio_device_info *get_device_info(S390PCIBusDevice *pbdev)
{
struct vfio_device_info *info = g_malloc0(argsz);
VFIOPCIDevice *vfio_pci;
int fd;
VFIOPCIDevice *vfio_pci = container_of(pbdev->pdev, VFIOPCIDevice, pdev);
vfio_pci = container_of(pbdev->pdev, VFIOPCIDevice, pdev);
fd = vfio_pci->vbasedev.fd;
/*
* If the specified argsz is not large enough to contain all capabilities
* it will be updated upon return from the ioctl. Retry until we have
* a big enough buffer to hold the entire capability chain. On error,
* just exit and rely on CLP defaults.
*/
retry:
info->argsz = argsz;
if (ioctl(fd, VFIO_DEVICE_GET_INFO, info)) {
trace_s390_pci_clp_dev_info(vfio_pci->vbasedev.name);
g_free(info);
return NULL;
}
if (info->argsz > argsz) {
argsz = info->argsz;
info = g_realloc(info, argsz);
goto retry;
}
return info;
return vfio_get_device_info(vfio_pci->vbasedev.fd);
}
/*
@ -335,7 +308,7 @@ bool s390_pci_get_host_fh(S390PCIBusDevice *pbdev, uint32_t *fh)
assert(fh);
info = get_device_info(pbdev, sizeof(*info));
info = get_device_info(pbdev);
if (!info) {
return false;
}
@ -356,7 +329,7 @@ void s390_pci_get_clp_info(S390PCIBusDevice *pbdev)
{
g_autofree struct vfio_device_info *info = NULL;
info = get_device_info(pbdev, sizeof(*info));
info = get_device_info(pbdev);
if (!info) {
return;
}

View File

@ -2846,11 +2846,35 @@ void vfio_put_group(VFIOGroup *group)
}
}
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_device(VFIOGroup *group, const char *name,
VFIODevice *vbasedev, Error **errp)
{
struct vfio_device_info dev_info = { .argsz = sizeof(dev_info) };
int ret, fd;
g_autofree struct vfio_device_info *info = NULL;
int fd;
fd = ioctl(group->fd, VFIO_GROUP_GET_DEVICE_FD, name);
if (fd < 0) {
@ -2862,11 +2886,11 @@ int vfio_get_device(VFIOGroup *group, const char *name,
return fd;
}
ret = ioctl(fd, VFIO_DEVICE_GET_INFO, &dev_info);
if (ret) {
info = vfio_get_device_info(fd);
if (!info) {
error_setg_errno(errp, errno, "error getting device info");
close(fd);
return ret;
return -1;
}
/*
@ -2894,14 +2918,14 @@ int vfio_get_device(VFIOGroup *group, const char *name,
vbasedev->group = group;
QLIST_INSERT_HEAD(&group->device_list, vbasedev, next);
vbasedev->num_irqs = dev_info.num_irqs;
vbasedev->num_regions = dev_info.num_regions;
vbasedev->flags = dev_info.flags;
vbasedev->num_irqs = info->num_irqs;
vbasedev->num_regions = info->num_regions;
vbasedev->flags = info->flags;
trace_vfio_get_device(name, dev_info.flags, dev_info.num_regions,
dev_info.num_irqs);
trace_vfio_get_device(name, info->flags, info->num_regions, info->num_irqs);
vbasedev->reset_works = !!(info->flags & VFIO_DEVICE_FLAGS_RESET);
vbasedev->reset_works = !!(dev_info.flags & VFIO_DEVICE_FLAGS_RESET);
return 0;
}

View File

@ -216,6 +216,7 @@ void vfio_region_finalize(VFIORegion *region);
void vfio_reset_handler(void *opaque);
VFIOGroup *vfio_get_group(int groupid, AddressSpace *as, Error **errp);
void vfio_put_group(VFIOGroup *group);
struct vfio_device_info *vfio_get_device_info(int fd);
int vfio_get_device(VFIOGroup *group, const char *name,
VFIODevice *vbasedev, Error **errp);