diff options
author | Eric Auger <eric.auger@linaro.org> | 2015-06-08 09:25:25 -0600 |
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committer | Alex Williamson <alex.williamson@redhat.com> | 2015-06-08 09:25:25 -0600 |
commit | 0ea2730bef0b764ce87f5d6859f9b1eac6069250 (patch) | |
tree | 56c3e63023f9f0b3c59d32bceed223ea99f99a20 /hw/vfio/platform.c | |
parent | 2e29dd7c44db30e3d3c108ab2a622cbdac6d16f0 (diff) |
hw/vfio/platform: vfio-platform skeleton
Minimal VFIO platform implementation supporting register space
user mapping but not IRQ assignment.
Signed-off-by: Kim Phillips <kim.phillips@linaro.org>
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Vikram Sethi <vikrams@codeaurora.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Diffstat (limited to 'hw/vfio/platform.c')
-rw-r--r-- | hw/vfio/platform.c | 287 |
1 files changed, 287 insertions, 0 deletions
diff --git a/hw/vfio/platform.c b/hw/vfio/platform.c new file mode 100644 index 0000000000..569a675cb2 --- /dev/null +++ b/hw/vfio/platform.c @@ -0,0 +1,287 @@ +/* + * vfio based device assignment support - platform devices + * + * Copyright Linaro Limited, 2014 + * + * Authors: + * Kim Phillips <kim.phillips@linaro.org> + * Eric Auger <eric.auger@linaro.org> + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + * + * Based on vfio based PCI device assignment support: + * Copyright Red Hat, Inc. 2012 + */ + +#include <linux/vfio.h> +#include <sys/ioctl.h> + +#include "hw/vfio/vfio-platform.h" +#include "qemu/error-report.h" +#include "qemu/range.h" +#include "sysemu/sysemu.h" +#include "exec/memory.h" +#include "hw/sysbus.h" +#include "trace.h" +#include "hw/platform-bus.h" + +/* VFIO skeleton */ + +static void vfio_platform_compute_needs_reset(VFIODevice *vbasedev) +{ + vbasedev->needs_reset = true; +} + +/* not implemented yet */ +static int vfio_platform_hot_reset_multi(VFIODevice *vbasedev) +{ + return -1; +} + +/** + * vfio_populate_device - Allocate and populate MMIO region + * structs according to driver returned information + * @vbasedev: the VFIO device handle + * + */ +static int vfio_populate_device(VFIODevice *vbasedev) +{ + int i, ret = -1; + VFIOPlatformDevice *vdev = + container_of(vbasedev, VFIOPlatformDevice, vbasedev); + + if (!(vbasedev->flags & VFIO_DEVICE_FLAGS_PLATFORM)) { + error_report("vfio: Um, this isn't a platform device"); + return ret; + } + + vdev->regions = g_malloc0_n(vbasedev->num_regions, + sizeof(VFIORegion *)); + + for (i = 0; i < vbasedev->num_regions; i++) { + struct vfio_region_info reg_info = { .argsz = sizeof(reg_info) }; + VFIORegion *ptr; + + vdev->regions[i] = g_malloc0(sizeof(VFIORegion)); + ptr = vdev->regions[i]; + reg_info.index = i; + ret = ioctl(vbasedev->fd, VFIO_DEVICE_GET_REGION_INFO, ®_info); + if (ret) { + error_report("vfio: Error getting region %d info: %m", i); + goto reg_error; + } + ptr->flags = reg_info.flags; + ptr->size = reg_info.size; + ptr->fd_offset = reg_info.offset; + ptr->nr = i; + ptr->vbasedev = vbasedev; + + trace_vfio_platform_populate_regions(ptr->nr, + (unsigned long)ptr->flags, + (unsigned long)ptr->size, + ptr->vbasedev->fd, + (unsigned long)ptr->fd_offset); + } + + return 0; +reg_error: + for (i = 0; i < vbasedev->num_regions; i++) { + g_free(vdev->regions[i]); + } + g_free(vdev->regions); + return ret; +} + +/* specialized functions for VFIO Platform devices */ +static VFIODeviceOps vfio_platform_ops = { + .vfio_compute_needs_reset = vfio_platform_compute_needs_reset, + .vfio_hot_reset_multi = vfio_platform_hot_reset_multi, +}; + +/** + * vfio_base_device_init - perform preliminary VFIO setup + * @vbasedev: the VFIO device handle + * + * Implement the VFIO command sequence that allows to discover + * assigned device resources: group extraction, device + * fd retrieval, resource query. + * Precondition: the device name must be initialized + */ +static int vfio_base_device_init(VFIODevice *vbasedev) +{ + VFIOGroup *group; + VFIODevice *vbasedev_iter; + char path[PATH_MAX], iommu_group_path[PATH_MAX], *group_name; + ssize_t len; + struct stat st; + int groupid; + int ret; + + /* name must be set prior to the call */ + if (!vbasedev->name || strchr(vbasedev->name, '/')) { + return -EINVAL; + } + + /* Check that the host device exists */ + g_snprintf(path, sizeof(path), "/sys/bus/platform/devices/%s/", + vbasedev->name); + + if (stat(path, &st) < 0) { + error_report("vfio: error: no such host device: %s", path); + return -errno; + } + + g_strlcat(path, "iommu_group", sizeof(path)); + len = readlink(path, iommu_group_path, sizeof(iommu_group_path)); + if (len < 0 || len >= sizeof(iommu_group_path)) { + error_report("vfio: error no iommu_group for device"); + return len < 0 ? -errno : -ENAMETOOLONG; + } + + iommu_group_path[len] = 0; + group_name = basename(iommu_group_path); + + if (sscanf(group_name, "%d", &groupid) != 1) { + error_report("vfio: error reading %s: %m", path); + return -errno; + } + + trace_vfio_platform_base_device_init(vbasedev->name, groupid); + + group = vfio_get_group(groupid, &address_space_memory); + if (!group) { + error_report("vfio: failed to get group %d", groupid); + return -ENOENT; + } + + g_snprintf(path, sizeof(path), "%s", vbasedev->name); + + QLIST_FOREACH(vbasedev_iter, &group->device_list, next) { + if (strcmp(vbasedev_iter->name, vbasedev->name) == 0) { + error_report("vfio: error: device %s is already attached", path); + vfio_put_group(group); + return -EBUSY; + } + } + ret = vfio_get_device(group, path, vbasedev); + if (ret) { + error_report("vfio: failed to get device %s", path); + vfio_put_group(group); + return ret; + } + + ret = vfio_populate_device(vbasedev); + if (ret) { + error_report("vfio: failed to populate device %s", path); + vfio_put_group(group); + } + + return ret; +} + +/** + * vfio_map_region - initialize the 2 memory regions for a given + * MMIO region index + * @vdev: the VFIO platform device handle + * @nr: the index of the region + * + * Init the top memory region and the mmapped memory region beneath + * VFIOPlatformDevice is used since VFIODevice is not a QOM Object + * and could not be passed to memory region functions +*/ +static void vfio_map_region(VFIOPlatformDevice *vdev, int nr) +{ + VFIORegion *region = vdev->regions[nr]; + uint64_t size = region->size; + char name[64]; + + if (!size) { + return; + } + + g_snprintf(name, sizeof(name), "VFIO %s region %d", + vdev->vbasedev.name, nr); + + /* A "slow" read/write mapping underlies all regions */ + memory_region_init_io(®ion->mem, OBJECT(vdev), &vfio_region_ops, + region, name, size); + + g_strlcat(name, " mmap", sizeof(name)); + + if (vfio_mmap_region(OBJECT(vdev), region, ®ion->mem, + ®ion->mmap_mem, ®ion->mmap, size, 0, name)) { + error_report("%s unsupported. Performance may be slow", name); + } +} + +/** + * vfio_platform_realize - the device realize function + * @dev: device state pointer + * @errp: error + * + * initialize the device, its memory regions and IRQ structures + * IRQ are started separately + */ +static void vfio_platform_realize(DeviceState *dev, Error **errp) +{ + VFIOPlatformDevice *vdev = VFIO_PLATFORM_DEVICE(dev); + SysBusDevice *sbdev = SYS_BUS_DEVICE(dev); + VFIODevice *vbasedev = &vdev->vbasedev; + int i, ret; + + vbasedev->type = VFIO_DEVICE_TYPE_PLATFORM; + vbasedev->ops = &vfio_platform_ops; + + trace_vfio_platform_realize(vbasedev->name, vdev->compat); + + ret = vfio_base_device_init(vbasedev); + if (ret) { + error_setg(errp, "vfio: vfio_base_device_init failed for %s", + vbasedev->name); + return; + } + + for (i = 0; i < vbasedev->num_regions; i++) { + vfio_map_region(vdev, i); + sysbus_init_mmio(sbdev, &vdev->regions[i]->mem); + } +} + +static const VMStateDescription vfio_platform_vmstate = { + .name = TYPE_VFIO_PLATFORM, + .unmigratable = 1, +}; + +static Property vfio_platform_dev_properties[] = { + DEFINE_PROP_STRING("host", VFIOPlatformDevice, vbasedev.name), + DEFINE_PROP_BOOL("x-mmap", VFIOPlatformDevice, vbasedev.allow_mmap, true), + DEFINE_PROP_END_OF_LIST(), +}; + +static void vfio_platform_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->realize = vfio_platform_realize; + dc->props = vfio_platform_dev_properties; + dc->vmsd = &vfio_platform_vmstate; + dc->desc = "VFIO-based platform device assignment"; + set_bit(DEVICE_CATEGORY_MISC, dc->categories); +} + +static const TypeInfo vfio_platform_dev_info = { + .name = TYPE_VFIO_PLATFORM, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(VFIOPlatformDevice), + .class_init = vfio_platform_class_init, + .class_size = sizeof(VFIOPlatformDeviceClass), + .abstract = true, +}; + +static void register_vfio_platform_dev_type(void) +{ + type_register_static(&vfio_platform_dev_info); +} + +type_init(register_vfio_platform_dev_type) |