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[PATCH V4 16/25] vfio-pci: cpr part 1
|
From: |
Steve Sistare |
|
Subject: |
[PATCH V4 16/25] vfio-pci: cpr part 1 |
|
Date: |
Tue, 6 Jul 2021 09:45:47 -0700 |
Enable vfio-pci devices to be saved and restored across an exec restart
of qemu.
At vfio creation time, save the value of vfio container, group, and device
descriptors in the environment.
In cprsave and cprexec, suspend the use of virtual addresses in DMA
mappings with VFIO_DMA_UNMAP_FLAG_VADDR, because guest ram will be remapped
at a different VA after exec. DMA to already-mapped pages continues. Save
the msi message area as part of vfio-pci vmstate, save the interrupt and
notifier eventfd's in the environment, and clear the close-on-exec flag
for the vfio descriptors. The flag is not cleared earlier because the
descriptors should not persist across miscellaneous fork and exec calls
that may be performed during normal operation.
On qemu restart, vfio_realize() finds the descriptor env vars, uses
the descriptors, and notes that the device is being reused. Device and
iommu state is already configured, so operations in vfio_realize that
would modify the configuration are skipped for a reused device, including
vfio ioctl's and writes to PCI configuration space. The result is that
vfio_realize constructs qemu data structures that reflect the current
state of the device. However, the reconstruction is not complete until
cprload is called. cprload loads the msi data and finds eventfds in the
environment. It rebuilds vector data structures and attaches the
interrupts to the new KVM instance. cprload then walks the flattened
ranges of the vfio_address_spaces and calls VFIO_DMA_MAP_FLAG_VADDR to
inform the kernel of the new VA's. Lastly, it starts the VM and suppresses
vfio device reset.
This functionality is delivered by 2 patches for clarity. Part 2 adds
eventfd and vector support.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
---
MAINTAINERS | 1 +
hw/pci/pci.c | 4 ++
hw/vfio/common.c | 69 +++++++++++++++++--
hw/vfio/cpr.c | 154 ++++++++++++++++++++++++++++++++++++++++++
hw/vfio/meson.build | 1 +
hw/vfio/pci.c | 66 +++++++++++++++++-
hw/vfio/trace-events | 1 +
include/hw/pci/pci.h | 1 +
include/hw/vfio/vfio-common.h | 5 ++
include/migration/cpr.h | 3 +
linux-headers/linux/vfio.h | 27 ++++++++
migration/cpr.c | 20 ++++++
12 files changed, 344 insertions(+), 8 deletions(-)
create mode 100644 hw/vfio/cpr.c
diff --git a/MAINTAINERS b/MAINTAINERS
index b844f3f..b69bbf5 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2847,6 +2847,7 @@ CPR
M: Steve Sistare <steven.sistare@oracle.com>
M: Mark Kanda <mark.kanda@oracle.com>
S: Maintained
+F: hw/vfio/cpr.c
F: include/migration/cpr.h
F: migration/cpr.c
F: qapi/cpr.json
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index e08d981..27019ca 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -308,6 +308,10 @@ static void pci_do_device_reset(PCIDevice *dev)
{
int r;
+ if (dev->reused) {
+ return;
+ }
+
pci_device_deassert_intx(dev);
assert(dev->irq_state == 0);
diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 9220e64..40c882f 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -31,6 +31,7 @@
#include "exec/memory.h"
#include "exec/ram_addr.h"
#include "hw/hw.h"
+#include "qemu/env.h"
#include "qemu/error-report.h"
#include "qemu/main-loop.h"
#include "qemu/range.h"
@@ -440,6 +441,10 @@ static int vfio_dma_unmap(VFIOContainer *container,
return vfio_dma_unmap_bitmap(container, iova, size, iotlb);
}
+ if (container->reused) {
+ return 0;
+ }
+
while (ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, &unmap)) {
/*
* The type1 backend has an off-by-one bug in the kernel (71a7d3d78e3c
@@ -463,6 +468,11 @@ static int vfio_dma_unmap(VFIOContainer *container,
return -errno;
}
+ if (unmap.size != size) {
+ warn_report("VFIO_UNMAP_DMA(0x%lx, 0x%lx) only unmaps 0x%llx",
+ iova, size, unmap.size);
+ }
+
return 0;
}
@@ -477,6 +487,10 @@ static int vfio_dma_map(VFIOContainer *container, hwaddr
iova,
.size = size,
};
+ if (container->reused) {
+ return 0;
+ }
+
if (!readonly) {
map.flags |= VFIO_DMA_MAP_FLAG_WRITE;
}
@@ -1603,6 +1617,10 @@ static int vfio_init_container(VFIOContainer *container,
int group_fd,
if (iommu_type < 0) {
return iommu_type;
}
+ if (container->reused) {
+ container->iommu_type = iommu_type;
+ return 0;
+ }
ret = ioctl(group_fd, VFIO_GROUP_SET_CONTAINER, &container->fd);
if (ret) {
@@ -1703,6 +1721,8 @@ static int vfio_connect_container(VFIOGroup *group,
AddressSpace *as,
{
VFIOContainer *container;
int ret, fd;
+ bool reused;
+ char name[40];
VFIOAddressSpace *space;
space = vfio_get_address_space(as);
@@ -1739,16 +1759,31 @@ static int vfio_connect_container(VFIOGroup *group,
AddressSpace *as,
return ret;
}
+ snprintf(name, sizeof(name), "vfio_container_for_group_%d",
group->groupid);
+ fd = getenv_fd(name);
+ reused = (fd >= 0);
+
QLIST_FOREACH(container, &space->containers, next) {
- if (!ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &container->fd)) {
- group->container = container;
- QLIST_INSERT_HEAD(&container->group_list, group, container_next);
+ if (container->fd == fd ||
+ !ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &container->fd)) {
+ break;
+ }
+ }
+
+ if (container) {
+ group->container = container;
+ QLIST_INSERT_HEAD(&container->group_list, group, container_next);
+ if (!reused) {
vfio_kvm_device_add_group(group);
- return 0;
+ setenv_fd(name, container->fd);
}
+ return 0;
+ }
+
+ if (!reused) {
+ fd = qemu_open_old("/dev/vfio/vfio", O_RDWR);
}
- fd = qemu_open_old("/dev/vfio/vfio", O_RDWR);
if (fd < 0) {
error_setg_errno(errp, errno, "failed to open /dev/vfio/vfio");
ret = -errno;
@@ -1766,6 +1801,7 @@ static int vfio_connect_container(VFIOGroup *group,
AddressSpace *as,
container = g_malloc0(sizeof(*container));
container->space = space;
container->fd = fd;
+ container->reused = reused;
container->error = NULL;
container->dirty_pages_supported = false;
QLIST_INIT(&container->giommu_list);
@@ -1893,6 +1929,7 @@ static int vfio_connect_container(VFIOGroup *group,
AddressSpace *as,
}
container->initialized = true;
+ setenv_fd(name, fd);
return 0;
listener_release_exit:
@@ -1920,6 +1957,7 @@ static void vfio_disconnect_container(VFIOGroup *group)
QLIST_REMOVE(group, container_next);
group->container = NULL;
+ unsetenv_fdv("vfio_container_for_group_%d", group->groupid);
/*
* Explicitly release the listener first before unset container,
@@ -1978,7 +2016,12 @@ VFIOGroup *vfio_get_group(int groupid, AddressSpace *as,
Error **errp)
group = g_malloc0(sizeof(*group));
snprintf(path, sizeof(path), "/dev/vfio/%d", groupid);
- group->fd = qemu_open_old(path, O_RDWR);
+
+ group->fd = getenv_fd(path);
+ if (group->fd < 0) {
+ group->fd = qemu_open_old(path, O_RDWR);
+ }
+
if (group->fd < 0) {
error_setg_errno(errp, errno, "failed to open %s", path);
goto free_group_exit;
@@ -2012,6 +2055,8 @@ VFIOGroup *vfio_get_group(int groupid, AddressSpace *as,
Error **errp)
QLIST_INSERT_HEAD(&vfio_group_list, group, next);
+ setenv_fd(path, group->fd);
+
return group;
close_fd_exit:
@@ -2036,6 +2081,7 @@ void vfio_put_group(VFIOGroup *group)
vfio_disconnect_container(group);
QLIST_REMOVE(group, next);
trace_vfio_put_group(group->fd);
+ unsetenv_fdv("/dev/vfio/%d", group->groupid);
close(group->fd);
g_free(group);
@@ -2049,8 +2095,14 @@ int vfio_get_device(VFIOGroup *group, const char *name,
{
struct vfio_device_info dev_info = { .argsz = sizeof(dev_info) };
int ret, fd;
+ bool reused;
+
+ fd = getenv_fd(name);
+ reused = (fd >= 0);
+ if (!reused) {
+ fd = ioctl(group->fd, VFIO_GROUP_GET_DEVICE_FD, name);
+ }
- fd = ioctl(group->fd, VFIO_GROUP_GET_DEVICE_FD, name);
if (fd < 0) {
error_setg_errno(errp, errno, "error getting device from group %d",
group->groupid);
@@ -2095,6 +2147,8 @@ int vfio_get_device(VFIOGroup *group, const char *name,
vbasedev->num_irqs = dev_info.num_irqs;
vbasedev->num_regions = dev_info.num_regions;
vbasedev->flags = dev_info.flags;
+ vbasedev->reused = reused;
+ setenv_fd(name, fd);
trace_vfio_get_device(name, dev_info.flags, dev_info.num_regions,
dev_info.num_irqs);
@@ -2111,6 +2165,7 @@ void vfio_put_base_device(VFIODevice *vbasedev)
QLIST_REMOVE(vbasedev, next);
vbasedev->group = NULL;
trace_vfio_put_base_device(vbasedev->fd);
+ unsetenv_fd(vbasedev->name);
close(vbasedev->fd);
}
diff --git a/hw/vfio/cpr.c b/hw/vfio/cpr.c
new file mode 100644
index 0000000..28f8a76
--- /dev/null
+++ b/hw/vfio/cpr.c
@@ -0,0 +1,154 @@
+/*
+ * Copyright (c) 2021 Oracle and/or its affiliates.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include <sys/ioctl.h>
+#include <linux/vfio.h>
+#include "hw/vfio/vfio-common.h"
+#include "sysemu/kvm.h"
+#include "qapi/error.h"
+#include "trace.h"
+
+static int
+vfio_dma_unmap_vaddr_all(VFIOContainer *container, Error **errp)
+{
+ struct vfio_iommu_type1_dma_unmap unmap = {
+ .argsz = sizeof(unmap),
+ .flags = VFIO_DMA_UNMAP_FLAG_VADDR | VFIO_DMA_UNMAP_FLAG_ALL,
+ .iova = 0,
+ .size = 0,
+ };
+ if (ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, &unmap)) {
+ error_setg_errno(errp, errno, "vfio_dma_unmap_vaddr_all");
+ return -errno;
+ }
+ return 0;
+}
+
+static int vfio_dma_map_vaddr(VFIOContainer *container, hwaddr iova,
+ ram_addr_t size, void *vaddr,
+ Error **errp)
+{
+ struct vfio_iommu_type1_dma_map map = {
+ .argsz = sizeof(map),
+ .flags = VFIO_DMA_MAP_FLAG_VADDR,
+ .vaddr = (__u64)(uintptr_t)vaddr,
+ .iova = iova,
+ .size = size,
+ };
+ if (ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map)) {
+ error_setg_errno(errp, errno,
+ "vfio_dma_map_vaddr(iova %lu, size %ld, va %p)",
+ iova, size, vaddr);
+ return -errno;
+ }
+ return 0;
+}
+
+static int
+vfio_region_remap(MemoryRegionSection *section, void *handle, Error **errp)
+{
+ MemoryRegion *mr = section->mr;
+ VFIOContainer *container = handle;
+ const char *name = memory_region_name(mr);
+ ram_addr_t size = int128_get64(section->size);
+ hwaddr offset, iova, roundup;
+ void *vaddr;
+
+ if (vfio_listener_skipped_section(section) || memory_region_is_iommu(mr)) {
+ return 0;
+ }
+
+ offset = section->offset_within_address_space;
+ iova = TARGET_PAGE_ALIGN(offset);
+ roundup = iova - offset;
+ size = (size - roundup) & TARGET_PAGE_MASK;
+ vaddr = memory_region_get_ram_ptr(mr) +
+ section->offset_within_region + roundup;
+
+ trace_vfio_region_remap(name, container->fd, iova, iova + size - 1, vaddr);
+ return vfio_dma_map_vaddr(container, iova, size, vaddr, errp);
+}
+
+bool vfio_cpr_capable(VFIOContainer *container, Error **errp)
+{
+ if (!ioctl(container->fd, VFIO_CHECK_EXTENSION, VFIO_UPDATE_VADDR) ||
+ !ioctl(container->fd, VFIO_CHECK_EXTENSION, VFIO_UNMAP_ALL)) {
+ error_setg(errp, "VFIO container does not support VFIO_UPDATE_VADDR "
+ "or VFIO_UNMAP_ALL");
+ return false;
+ } else {
+ return true;
+ }
+}
+
+int vfio_cprsave(Error **errp)
+{
+ VFIOAddressSpace *space, *last_space;
+ VFIOContainer *container, *last_container;
+
+ QLIST_FOREACH(space, &vfio_address_spaces, list) {
+ QLIST_FOREACH(container, &space->containers, next) {
+ if (!vfio_cpr_capable(container, errp)) {
+ return 1;
+ }
+ }
+ }
+
+ QLIST_FOREACH(space, &vfio_address_spaces, list) {
+ QLIST_FOREACH(container, &space->containers, next) {
+ if (vfio_dma_unmap_vaddr_all(container, errp)) {
+ goto unwind;
+ }
+ }
+ }
+ return 0;
+
+unwind:
+ last_space = space;
+ last_container = container;
+ QLIST_FOREACH(space, &vfio_address_spaces, list) {
+ QLIST_FOREACH(container, &space->containers, next) {
+ Error *err;
+
+ if (space == last_space && container == last_container) {
+ break;
+ }
+ if (as_flat_walk(space->as, vfio_region_remap, container, &err)) {
+ error_prepend(errp, "%s", error_get_pretty(err));
+ error_free(err);
+ }
+ }
+ }
+ return 1;
+}
+
+int vfio_cprload(Error **errp)
+{
+ VFIOAddressSpace *space;
+ VFIOContainer *container;
+ VFIOGroup *group;
+ VFIODevice *vbasedev;
+
+ QLIST_FOREACH(space, &vfio_address_spaces, list) {
+ QLIST_FOREACH(container, &space->containers, next) {
+ if (!vfio_cpr_capable(container, errp)) {
+ return 1;
+ }
+ container->reused = false;
+ if (as_flat_walk(space->as, vfio_region_remap, container, errp)) {
+ return 1;
+ }
+ }
+ }
+ QLIST_FOREACH(group, &vfio_group_list, next) {
+ QLIST_FOREACH(vbasedev, &group->device_list, next) {
+ vbasedev->reused = false;
+ }
+ }
+ return 0;
+}
diff --git a/hw/vfio/meson.build b/hw/vfio/meson.build
index da9af29..e247b2b 100644
--- a/hw/vfio/meson.build
+++ b/hw/vfio/meson.build
@@ -5,6 +5,7 @@ vfio_ss.add(files(
'migration.c',
))
vfio_ss.add(when: 'CONFIG_VFIO_PCI', if_true: files(
+ 'cpr.c',
'display.c',
'pci-quirks.c',
'pci.c',
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index bc656e9..f3a9361 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -29,6 +29,8 @@
#include "hw/qdev-properties.h"
#include "hw/qdev-properties-system.h"
#include "migration/vmstate.h"
+#include "migration/cpr.h"
+#include "qemu/env.h"
#include "qemu/error-report.h"
#include "qemu/main-loop.h"
#include "qemu/module.h"
@@ -1657,6 +1659,7 @@ static void vfio_bars_prepare(VFIOPCIDevice *vdev)
static void vfio_bar_register(VFIOPCIDevice *vdev, int nr)
{
VFIOBAR *bar = &vdev->bars[nr];
+ PCIDevice *pdev = &vdev->pdev;
char *name;
if (!bar->size) {
@@ -1677,7 +1680,7 @@ static void vfio_bar_register(VFIOPCIDevice *vdev, int nr)
}
}
- pci_register_bar(&vdev->pdev, nr, bar->type, bar->mr);
+ pci_register_bar(pdev, nr, bar->type, bar->mr);
}
static void vfio_bars_register(VFIOPCIDevice *vdev)
@@ -2889,6 +2892,7 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
vfio_put_group(group);
goto error;
}
+ pdev->reused = vdev->vbasedev.reused;
vfio_populate_device(vdev, &err);
if (err) {
@@ -3158,6 +3162,10 @@ static void vfio_pci_reset(DeviceState *dev)
{
VFIOPCIDevice *vdev = VFIO_PCI(dev);
+ if (vdev->pdev.reused) {
+ return;
+ }
+
trace_vfio_pci_reset(vdev->vbasedev.name);
vfio_pci_pre_reset(vdev);
@@ -3265,6 +3273,61 @@ static Property vfio_pci_dev_properties[] = {
DEFINE_PROP_END_OF_LIST(),
};
+static void vfio_merge_config(VFIOPCIDevice *vdev)
+{
+ PCIDevice *pdev = &vdev->pdev;
+ int size = MIN(pci_config_size(pdev), vdev->config_size);
+ uint8_t *phys_config = g_malloc(size);
+ uint32_t mask;
+ int ret, i;
+
+ ret = pread(vdev->vbasedev.fd, phys_config, size, vdev->config_offset);
+ if (ret < size) {
+ ret = ret < 0 ? errno : EFAULT;
+ error_report("failed to read device config space: %s", strerror(ret));
+ return;
+ }
+
+ for (i = 0; i < size; i++) {
+ mask = vdev->emulated_config_bits[i];
+ pdev->config[i] = (pdev->config[i] & mask) | (phys_config[i] & ~mask);
+ }
+
+ g_free(phys_config);
+}
+
+static int vfio_pci_post_load(void *opaque, int version_id)
+{
+ VFIOPCIDevice *vdev = opaque;
+ PCIDevice *pdev = &vdev->pdev;
+ bool enabled;
+
+ vfio_merge_config(vdev);
+
+ pdev->reused = false;
+ enabled = pci_get_word(pdev->config + PCI_COMMAND) & PCI_COMMAND_MASTER;
+ memory_region_set_enabled(&pdev->bus_master_enable_region, enabled);
+
+ return 0;
+}
+
+static bool vfio_pci_needed(void *opaque)
+{
+ return cpr_mode() == CPR_MODE_RESTART;
+}
+
+static const VMStateDescription vfio_pci_vmstate = {
+ .name = "vfio-pci",
+ .unmigratable = 1,
+ .version_id = 0,
+ .minimum_version_id = 0,
+ .post_load = vfio_pci_post_load,
+ .needed = vfio_pci_needed,
+ .fields = (VMStateField[]) {
+ VMSTATE_END_OF_LIST()
+ }
+};
+
static void vfio_pci_dev_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
@@ -3272,6 +3335,7 @@ static void vfio_pci_dev_class_init(ObjectClass *klass,
void *data)
dc->reset = vfio_pci_reset;
device_class_set_props(dc, vfio_pci_dev_properties);
+ dc->vmsd = &vfio_pci_vmstate;
dc->desc = "VFIO-based PCI device assignment";
set_bit(DEVICE_CATEGORY_MISC, dc->categories);
pdc->realize = vfio_realize;
diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events
index 079f53a..0f8b166 100644
--- a/hw/vfio/trace-events
+++ b/hw/vfio/trace-events
@@ -118,6 +118,7 @@ vfio_region_sparse_mmap_header(const char *name, int index,
int nr_areas) "Devic
vfio_region_sparse_mmap_entry(int i, unsigned long start, unsigned long end)
"sparse entry %d [0x%lx - 0x%lx]"
vfio_get_dev_region(const char *name, int index, uint32_t type, uint32_t
subtype) "%s index %d, %08x/%0x8"
vfio_dma_unmap_overflow_workaround(void) ""
+vfio_region_remap(const char *name, int fd, uint64_t iova_start, uint64_t
iova_end, void *vaddr) "%s fd %d 0x%"PRIx64" - 0x%"PRIx64" [%p]"
# platform.c
vfio_platform_base_device_init(char *name, int groupid) "%s belongs to group
#%d"
diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
index bef3e49..add7f46 100644
--- a/include/hw/pci/pci.h
+++ b/include/hw/pci/pci.h
@@ -360,6 +360,7 @@ struct PCIDevice {
/* ID of standby device in net_failover pair */
char *failover_pair_id;
uint32_t acpi_index;
+ bool reused;
};
void pci_register_bar(PCIDevice *pci_dev, int region_num,
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index 00acb85..b46d850 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -85,6 +85,7 @@ typedef struct VFIOContainer {
Error *error;
bool initialized;
bool dirty_pages_supported;
+ bool reused;
uint64_t dirty_pgsizes;
uint64_t max_dirty_bitmap_size;
unsigned long pgsizes;
@@ -124,6 +125,7 @@ typedef struct VFIODevice {
bool no_mmap;
bool ram_block_discard_allowed;
bool enable_migration;
+ bool reused;
VFIODeviceOps *ops;
unsigned int num_irqs;
unsigned int num_regions;
@@ -200,6 +202,9 @@ VFIOGroup *vfio_get_group(int groupid, AddressSpace *as,
Error **errp);
void vfio_put_group(VFIOGroup *group);
int vfio_get_device(VFIOGroup *group, const char *name,
VFIODevice *vbasedev, Error **errp);
+int vfio_cprsave(Error **errp);
+int vfio_cprload(Error **errp);
+bool vfio_cpr_capable(VFIOContainer *container, Error **errp);
extern const MemoryRegionOps vfio_region_ops;
typedef QLIST_HEAD(VFIOGroupList, VFIOGroup) VFIOGroupList;
diff --git a/include/migration/cpr.h b/include/migration/cpr.h
index bffee19..1ea5046 100644
--- a/include/migration/cpr.h
+++ b/include/migration/cpr.h
@@ -10,6 +10,9 @@
#include "qapi/qapi-types-cpr.h"
+#define CPR_MODE_NONE ((CprMode)(-1))
+
+CprMode cpr_mode(void);
void cprsave(const char *file, CprMode mode, Error **errp);
void cprexec(strList *args, Error **errp);
void cprload(const char *file, Error **errp);
diff --git a/linux-headers/linux/vfio.h b/linux-headers/linux/vfio.h
index 609099e..bc3a66e 100644
--- a/linux-headers/linux/vfio.h
+++ b/linux-headers/linux/vfio.h
@@ -46,6 +46,12 @@
*/
#define VFIO_NOIOMMU_IOMMU 8
+/* Supports VFIO_DMA_UNMAP_FLAG_ALL */
+#define VFIO_UNMAP_ALL 9
+
+/* Supports VFIO DMA map and unmap with the VADDR flag */
+#define VFIO_UPDATE_VADDR 10
+
/*
* The IOCTL interface is designed for extensibility by embedding the
* structure length (argsz) and flags into structures passed between
@@ -1074,12 +1080,22 @@ struct vfio_iommu_type1_info_dma_avail {
*
* Map process virtual addresses to IO virtual addresses using the
* provided struct vfio_dma_map. Caller sets argsz. READ &/ WRITE required.
+ *
+ * If flags & VFIO_DMA_MAP_FLAG_VADDR, record the new base vaddr for iova, and
+ * unblock translation of host virtual addresses in the iova range. The vaddr
+ * must have previously been invalidated with VFIO_DMA_UNMAP_FLAG_VADDR. To
+ * maintain memory consistency within the user application, the updated vaddr
+ * must address the same memory object as originally mapped. Failure to do so
+ * will result in user memory corruption and/or device misbehavior. iova and
+ * size must match those in the original MAP_DMA call. Protection is not
+ * changed, and the READ & WRITE flags must be 0.
*/
struct vfio_iommu_type1_dma_map {
__u32 argsz;
__u32 flags;
#define VFIO_DMA_MAP_FLAG_READ (1 << 0) /* readable from device
*/
#define VFIO_DMA_MAP_FLAG_WRITE (1 << 1) /* writable from device */
+#define VFIO_DMA_MAP_FLAG_VADDR (1 << 2)
__u64 vaddr; /* Process virtual address */
__u64 iova; /* IO virtual address */
__u64 size; /* Size of mapping (bytes) */
@@ -1102,6 +1118,7 @@ struct vfio_bitmap {
* field. No guarantee is made to the user that arbitrary unmaps of iova
* or size different from those used in the original mapping call will
* succeed.
+ *
* VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP should be set to get the dirty bitmap
* before unmapping IO virtual addresses. When this flag is set, the user must
* provide a struct vfio_bitmap in data[]. User must provide zero-allocated
@@ -1111,11 +1128,21 @@ struct vfio_bitmap {
* indicates that the page at that offset from iova is dirty. A Bitmap of the
* pages in the range of unmapped size is returned in the user-provided
* vfio_bitmap.data.
+ *
+ * If flags & VFIO_DMA_UNMAP_FLAG_ALL, unmap all addresses. iova and size
+ * must be 0. This cannot be combined with the get-dirty-bitmap flag.
+ *
+ * If flags & VFIO_DMA_UNMAP_FLAG_VADDR, do not unmap, but invalidate host
+ * virtual addresses in the iova range. Tasks that attempt to translate an
+ * iova's vaddr will block. DMA to already-mapped pages continues. This
+ * cannot be combined with the get-dirty-bitmap flag.
*/
struct vfio_iommu_type1_dma_unmap {
__u32 argsz;
__u32 flags;
#define VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP (1 << 0)
+#define VFIO_DMA_UNMAP_FLAG_ALL (1 << 1)
+#define VFIO_DMA_UNMAP_FLAG_VADDR (1 << 2)
__u64 iova; /* IO virtual address */
__u64 size; /* Size of mapping (bytes) */
__u8 data[];
diff --git a/migration/cpr.c b/migration/cpr.c
index fb57dec..578466c 100644
--- a/migration/cpr.c
+++ b/migration/cpr.c
@@ -31,6 +31,13 @@
#include "hw/virtio/vhost.h"
#include "qemu/env.h"
+static CprMode cpr_active_mode = CPR_MODE_NONE;
+
+CprMode cpr_mode(void)
+{
+ return cpr_active_mode;
+}
+
QEMUFile *qf_file_open(const char *path, int flags, int mode,
const char *name, Error **errp)
{
@@ -92,6 +99,7 @@ void cprsave(const char *file, CprMode mode, Error **errp)
}
vm_stop(RUN_STATE_SAVE_VM);
+ cpr_active_mode = mode;
ret = qemu_save_device_state(f);
qemu_fclose(f);
if (ret < 0) {
@@ -105,6 +113,7 @@ err:
if (saved_vm_running) {
vm_start();
}
+ cpr_active_mode = CPR_MODE_NONE;
done:
return;
}
@@ -125,6 +134,13 @@ void cprexec(strList *args, Error **errp)
error_setg(errp, "runstate is not save-vm");
return;
}
+ if (cpr_active_mode != CPR_MODE_RESTART) {
+ error_setg(errp, "cprexec requires cprsave with restart mode");
+ return;
+ }
+ if (vfio_cprsave(errp)) {
+ return;
+ }
walkenv(FD_PREFIX, preserve_fd, 0);
qemu_system_exec_request(args);
}
@@ -158,6 +174,10 @@ void cprload(const char *file, Error **errp)
return;
}
+ if (vfio_cprload(errp)) {
+ return;
+ }
+
state = global_state_get_runstate();
if (state == RUN_STATE_RUNNING) {
vm_start();
--
1.8.3.1
- [PATCH V4 19/25] hostmem-memfd: cpr support, (continued)
- [PATCH V4 19/25] hostmem-memfd: cpr support, Steve Sistare, 2021/07/06
- [PATCH V4 18/25] vhost: reset vhost devices upon cprsave, Steve Sistare, 2021/07/06
- [PATCH V4 21/25] chardev: cpr for simple devices, Steve Sistare, 2021/07/06
- [PATCH V4 20/25] chardev: cpr framework, Steve Sistare, 2021/07/06
- [PATCH V4 22/25] chardev: cpr for pty, Steve Sistare, 2021/07/06
- [PATCH V4 23/25] chardev: cpr for sockets, Steve Sistare, 2021/07/06
- [PATCH V4 25/25] simplify savevm, Steve Sistare, 2021/07/06
- [PATCH V4 24/25] cpr: only-cpr-capable option, Steve Sistare, 2021/07/06
- [PATCH V4 04/25] cpr: HMP interfaces for reboot, Steve Sistare, 2021/07/06
- [PATCH V4 16/25] vfio-pci: cpr part 1,
Steve Sistare <=
- Re: [PATCH V4 00/25] Live Update, Marc-André Lureau, 2021/07/07