diff options
Diffstat (limited to 'hw/vfio/region.c')
| -rw-r--r-- | hw/vfio/region.c | 394 |
1 files changed, 394 insertions, 0 deletions
diff --git a/hw/vfio/region.c b/hw/vfio/region.c new file mode 100644 index 0000000000..08cd69e704 --- /dev/null +++ b/hw/vfio/region.c @@ -0,0 +1,394 @@ +/* + * VFIO regions + * + * 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 "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" + +/* + * IO Port/MMIO - Beware of the endians, VFIO is always little endian + */ +void vfio_region_write(void *opaque, hwaddr addr, + uint64_t data, unsigned size) +{ + VFIORegion *region = opaque; + VFIODevice *vbasedev = region->vbasedev; + union { + uint8_t byte; + uint16_t word; + uint32_t dword; + uint64_t qword; + } buf; + + switch (size) { + case 1: + buf.byte = data; + break; + case 2: + buf.word = cpu_to_le16(data); + break; + case 4: + buf.dword = cpu_to_le32(data); + break; + case 8: + buf.qword = cpu_to_le64(data); + break; + default: + hw_error("vfio: unsupported write size, %u bytes", size); + break; + } + + if (pwrite(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) { + error_report("%s(%s:region%d+0x%"HWADDR_PRIx", 0x%"PRIx64 + ",%d) failed: %m", + __func__, vbasedev->name, region->nr, + addr, data, size); + } + + trace_vfio_region_write(vbasedev->name, region->nr, addr, data, size); + + /* + * A read or write to a BAR always signals an INTx EOI. This will + * do nothing if not pending (including not in INTx mode). We assume + * that a BAR access is in response to an interrupt and that BAR + * accesses will service the interrupt. Unfortunately, we don't know + * which access will service the interrupt, so we're potentially + * getting quite a few host interrupts per guest interrupt. + */ + vbasedev->ops->vfio_eoi(vbasedev); +} + +uint64_t vfio_region_read(void *opaque, + hwaddr addr, unsigned size) +{ + VFIORegion *region = opaque; + VFIODevice *vbasedev = region->vbasedev; + union { + uint8_t byte; + uint16_t word; + uint32_t dword; + uint64_t qword; + } buf; + uint64_t data = 0; + + if (pread(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) { + error_report("%s(%s:region%d+0x%"HWADDR_PRIx", %d) failed: %m", + __func__, vbasedev->name, region->nr, + addr, size); + return (uint64_t)-1; + } + switch (size) { + case 1: + data = buf.byte; + break; + case 2: + data = le16_to_cpu(buf.word); + break; + case 4: + data = le32_to_cpu(buf.dword); + break; + case 8: + data = le64_to_cpu(buf.qword); + break; + default: + hw_error("vfio: unsupported read size, %u bytes", size); + break; + } + + trace_vfio_region_read(vbasedev->name, region->nr, addr, size, data); + + /* Same as write above */ + vbasedev->ops->vfio_eoi(vbasedev); + + return data; +} + +static const MemoryRegionOps vfio_region_ops = { + .read = vfio_region_read, + .write = vfio_region_write, + .endianness = DEVICE_LITTLE_ENDIAN, + .valid = { + .min_access_size = 1, + .max_access_size = 8, + }, + .impl = { + .min_access_size = 1, + .max_access_size = 8, + }, +}; + +static int vfio_setup_region_sparse_mmaps(VFIORegion *region, + struct vfio_region_info *info) +{ + struct vfio_info_cap_header *hdr; + struct vfio_region_info_cap_sparse_mmap *sparse; + int i, j; + + hdr = vfio_get_region_info_cap(info, VFIO_REGION_INFO_CAP_SPARSE_MMAP); + if (!hdr) { + return -ENODEV; + } + + sparse = container_of(hdr, struct vfio_region_info_cap_sparse_mmap, header); + + trace_vfio_region_sparse_mmap_header(region->vbasedev->name, + region->nr, sparse->nr_areas); + + region->mmaps = g_new0(VFIOMmap, sparse->nr_areas); + + for (i = 0, j = 0; i < sparse->nr_areas; i++) { + if (sparse->areas[i].size) { + trace_vfio_region_sparse_mmap_entry(i, sparse->areas[i].offset, + sparse->areas[i].offset + + sparse->areas[i].size - 1); + region->mmaps[j].offset = sparse->areas[i].offset; + region->mmaps[j].size = sparse->areas[i].size; + j++; + } + } + + region->nr_mmaps = j; + region->mmaps = g_realloc(region->mmaps, j * sizeof(VFIOMmap)); + + return 0; +} + +int vfio_region_setup(Object *obj, VFIODevice *vbasedev, VFIORegion *region, + int index, const char *name) +{ + g_autofree struct vfio_region_info *info = NULL; + int ret; + + ret = vfio_get_region_info(vbasedev, index, &info); + if (ret) { + return ret; + } + + region->vbasedev = vbasedev; + region->flags = info->flags; + region->size = info->size; + region->fd_offset = info->offset; + region->nr = index; + + if (region->size) { + region->mem = g_new0(MemoryRegion, 1); + memory_region_init_io(region->mem, obj, &vfio_region_ops, + region, name, region->size); + + if (!vbasedev->no_mmap && + region->flags & VFIO_REGION_INFO_FLAG_MMAP) { + + ret = vfio_setup_region_sparse_mmaps(region, info); + + if (ret) { + region->nr_mmaps = 1; + region->mmaps = g_new0(VFIOMmap, region->nr_mmaps); + region->mmaps[0].offset = 0; + region->mmaps[0].size = region->size; + } + } + } + + trace_vfio_region_setup(vbasedev->name, index, name, + region->flags, region->fd_offset, region->size); + return 0; +} + +static void vfio_subregion_unmap(VFIORegion *region, int index) +{ + trace_vfio_region_unmap(memory_region_name(®ion->mmaps[index].mem), + region->mmaps[index].offset, + region->mmaps[index].offset + + region->mmaps[index].size - 1); + memory_region_del_subregion(region->mem, ®ion->mmaps[index].mem); + munmap(region->mmaps[index].mmap, region->mmaps[index].size); + object_unparent(OBJECT(®ion->mmaps[index].mem)); + region->mmaps[index].mmap = NULL; +} + +int vfio_region_mmap(VFIORegion *region) +{ + int i, ret, prot = 0; + char *name; + + if (!region->mem) { + return 0; + } + + prot |= region->flags & VFIO_REGION_INFO_FLAG_READ ? PROT_READ : 0; + prot |= region->flags & VFIO_REGION_INFO_FLAG_WRITE ? PROT_WRITE : 0; + + for (i = 0; i < region->nr_mmaps; i++) { + size_t align = MIN(1ULL << ctz64(region->mmaps[i].size), 1 * GiB); + void *map_base, *map_align; + + /* + * Align the mmap for more efficient mapping in the kernel. Ideally + * we'd know the PMD and PUD mapping sizes to use as discrete alignment + * intervals, but we don't. As of Linux v6.12, the largest PUD size + * supporting huge pfnmap is 1GiB (ARCH_SUPPORTS_PUD_PFNMAP is only set + * on x86_64). Align by power-of-two size, capped at 1GiB. + * + * NB. qemu_memalign() and friends actually allocate memory, whereas + * the region size here can exceed host memory, therefore we manually + * create an oversized anonymous mapping and clean it up for alignment. + */ + map_base = mmap(0, region->mmaps[i].size + align, PROT_NONE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (map_base == MAP_FAILED) { + ret = -errno; + goto no_mmap; + } + + map_align = (void *)ROUND_UP((uintptr_t)map_base, (uintptr_t)align); + munmap(map_base, map_align - map_base); + munmap(map_align + region->mmaps[i].size, + align - (map_align - map_base)); + + region->mmaps[i].mmap = mmap(map_align, region->mmaps[i].size, prot, + MAP_SHARED | MAP_FIXED, + region->vbasedev->fd, + region->fd_offset + + region->mmaps[i].offset); + if (region->mmaps[i].mmap == MAP_FAILED) { + ret = -errno; + goto no_mmap; + } + + name = g_strdup_printf("%s mmaps[%d]", + memory_region_name(region->mem), i); + memory_region_init_ram_device_ptr(®ion->mmaps[i].mem, + memory_region_owner(region->mem), + name, region->mmaps[i].size, + region->mmaps[i].mmap); + g_free(name); + memory_region_add_subregion(region->mem, region->mmaps[i].offset, + ®ion->mmaps[i].mem); + + trace_vfio_region_mmap(memory_region_name(®ion->mmaps[i].mem), + region->mmaps[i].offset, + region->mmaps[i].offset + + region->mmaps[i].size - 1); + } + + return 0; + +no_mmap: + trace_vfio_region_mmap_fault(memory_region_name(region->mem), i, + region->fd_offset + region->mmaps[i].offset, + region->fd_offset + region->mmaps[i].offset + + region->mmaps[i].size - 1, ret); + + region->mmaps[i].mmap = NULL; + + for (i--; i >= 0; i--) { + vfio_subregion_unmap(region, i); + } + + return ret; +} + +void vfio_region_unmap(VFIORegion *region) +{ + int i; + + if (!region->mem) { + return; + } + + for (i = 0; i < region->nr_mmaps; i++) { + if (region->mmaps[i].mmap) { + vfio_subregion_unmap(region, i); + } + } +} + +void vfio_region_exit(VFIORegion *region) +{ + int i; + + if (!region->mem) { + return; + } + + for (i = 0; i < region->nr_mmaps; i++) { + if (region->mmaps[i].mmap) { + memory_region_del_subregion(region->mem, ®ion->mmaps[i].mem); + } + } + + trace_vfio_region_exit(region->vbasedev->name, region->nr); +} + +void vfio_region_finalize(VFIORegion *region) +{ + int i; + + if (!region->mem) { + return; + } + + for (i = 0; i < region->nr_mmaps; i++) { + if (region->mmaps[i].mmap) { + munmap(region->mmaps[i].mmap, region->mmaps[i].size); + object_unparent(OBJECT(®ion->mmaps[i].mem)); + } + } + + object_unparent(OBJECT(region->mem)); + + g_free(region->mem); + g_free(region->mmaps); + + trace_vfio_region_finalize(region->vbasedev->name, region->nr); + + region->mem = NULL; + region->mmaps = NULL; + region->nr_mmaps = 0; + region->size = 0; + region->flags = 0; + region->nr = 0; +} + +void vfio_region_mmaps_set_enabled(VFIORegion *region, bool enabled) +{ + int i; + + if (!region->mem) { + return; + } + + for (i = 0; i < region->nr_mmaps; i++) { + if (region->mmaps[i].mmap) { + memory_region_set_enabled(®ion->mmaps[i].mem, enabled); + } + } + + trace_vfio_region_mmaps_set_enabled(memory_region_name(region->mem), + enabled); +} |