diff options
| -rw-r--r-- | hw/s390x/meson.build | 1 | ||||
| -rw-r--r-- | hw/s390x/s390-pci-vfio.c | 54 | ||||
| -rw-r--r-- | include/hw/s390x/s390-pci-vfio.h | 24 |
3 files changed, 79 insertions, 0 deletions
diff --git a/hw/s390x/meson.build b/hw/s390x/meson.build index 948ceae7a7..f4663a8355 100644 --- a/hw/s390x/meson.build +++ b/hw/s390x/meson.build @@ -27,6 +27,7 @@ s390x_ss.add(when: 'CONFIG_KVM', if_true: files( )) s390x_ss.add(when: 'CONFIG_S390_CCW_VIRTIO', if_true: files('s390-virtio-ccw.c')) s390x_ss.add(when: 'CONFIG_TERMINAL3270', if_true: files('3270-ccw.c')) +s390x_ss.add(when: 'CONFIG_LINUX', if_true: files('s390-pci-vfio.c')) virtio_ss = ss.source_set() virtio_ss.add(files('virtio-ccw.c')) diff --git a/hw/s390x/s390-pci-vfio.c b/hw/s390x/s390-pci-vfio.c new file mode 100644 index 0000000000..cb3f4d98ad --- /dev/null +++ b/hw/s390x/s390-pci-vfio.c @@ -0,0 +1,54 @@ +/* + * s390 vfio-pci interfaces + * + * Copyright 2020 IBM Corp. + * Author(s): Matthew Rosato <mjrosato@linux.ibm.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or (at + * your option) any later version. See the COPYING file in the top-level + * directory. + */ + +#include <sys/ioctl.h> + +#include "qemu/osdep.h" +#include "hw/s390x/s390-pci-vfio.h" +#include "hw/vfio/vfio-common.h" + +/* + * Get the current DMA available count from vfio. Returns true if vfio is + * limiting DMA requests, false otherwise. The current available count read + * from vfio is returned in avail. + */ +bool s390_pci_update_dma_avail(int fd, unsigned int *avail) +{ + g_autofree struct vfio_iommu_type1_info *info; + uint32_t argsz; + + assert(avail); + + argsz = sizeof(struct vfio_iommu_type1_info); + info = g_malloc0(argsz); + + /* + * 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. + */ +retry: + info->argsz = argsz; + + if (ioctl(fd, VFIO_IOMMU_GET_INFO, info)) { + return false; + } + + if (info->argsz > argsz) { + argsz = info->argsz; + info = g_realloc(info, argsz); + goto retry; + } + + /* If the capability exists, update with the current value */ + return vfio_get_info_dma_avail(info, avail); +} + diff --git a/include/hw/s390x/s390-pci-vfio.h b/include/hw/s390x/s390-pci-vfio.h new file mode 100644 index 0000000000..1727292e9b --- /dev/null +++ b/include/hw/s390x/s390-pci-vfio.h @@ -0,0 +1,24 @@ +/* + * s390 vfio-pci interfaces + * + * Copyright 2020 IBM Corp. + * Author(s): Matthew Rosato <mjrosato@linux.ibm.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or (at + * your option) any later version. See the COPYING file in the top-level + * directory. + */ + +#ifndef HW_S390_PCI_VFIO_H +#define HW_S390_PCI_VFIO_H + +#ifdef CONFIG_LINUX +bool s390_pci_update_dma_avail(int fd, unsigned int *avail); +#else +static inline bool s390_pci_update_dma_avail(int fd, unsigned int *avail) +{ + return false; +} +#endif + +#endif |