Message ID | 1603449643-12851-9-git-send-email-kwankhede@nvidia.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | Add migration support for VFIO devices | expand |
Reviewed-by: Yan Zhao <yan.y.zhao@intel.com> On Fri, Oct 23, 2020 at 04:10:34PM +0530, Kirti Wankhede wrote: > Added .save_live_pending, .save_live_iterate and .save_live_complete_precopy > functions. These functions handles pre-copy and stop-and-copy phase. > > In _SAVING|_RUNNING device state or pre-copy phase: > - read pending_bytes. If pending_bytes > 0, go through below steps. > - read data_offset - indicates kernel driver to write data to staging > buffer. > - read data_size - amount of data in bytes written by vendor driver in > migration region. > - read data_size bytes of data from data_offset in the migration region. > - Write data packet to file stream as below: > {VFIO_MIG_FLAG_DEV_DATA_STATE, data_size, actual data, > VFIO_MIG_FLAG_END_OF_STATE } > > In _SAVING device state or stop-and-copy phase > a. read config space of device and save to migration file stream. This > doesn't need to be from vendor driver. Any other special config state > from driver can be saved as data in following iteration. > b. read pending_bytes. If pending_bytes > 0, go through below steps. > c. read data_offset - indicates kernel driver to write data to staging > buffer. > d. read data_size - amount of data in bytes written by vendor driver in > migration region. > e. read data_size bytes of data from data_offset in the migration region. > f. Write data packet as below: > {VFIO_MIG_FLAG_DEV_DATA_STATE, data_size, actual data} > g. iterate through steps b to f while (pending_bytes > 0) > h. Write {VFIO_MIG_FLAG_END_OF_STATE} > > When data region is mapped, its user's responsibility to read data from > data_offset of data_size before moving to next steps. > > Added fix suggested by Artem Polyakov to reset pending_bytes in > vfio_save_iterate(). > Added fix suggested by Zhi Wang to add 0 as data size in migration stream and > add END_OF_STATE delimiter to indicate phase complete. > > Suggested-by: Artem Polyakov <artemp@nvidia.com> > Suggested-by: Zhi Wang <zhi.wang.linux@gmail.com> > Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com> > Reviewed-by: Neo Jia <cjia@nvidia.com> > --- > hw/vfio/migration.c | 276 ++++++++++++++++++++++++++++++++++++++++++ > hw/vfio/trace-events | 6 + > include/hw/vfio/vfio-common.h | 1 + > 3 files changed, 283 insertions(+) > > diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c > index 94d2bdae5c54..be9e4aba541d 100644 > --- a/hw/vfio/migration.c > +++ b/hw/vfio/migration.c > @@ -148,6 +148,151 @@ static int vfio_migration_set_state(VFIODevice *vbasedev, uint32_t mask, > return 0; > } > > +static void *get_data_section_size(VFIORegion *region, uint64_t data_offset, > + uint64_t data_size, uint64_t *size) > +{ > + void *ptr = NULL; > + uint64_t limit = 0; > + int i; > + > + if (!region->mmaps) { > + if (size) { > + *size = MIN(data_size, region->size - data_offset); > + } > + return ptr; > + } > + > + for (i = 0; i < region->nr_mmaps; i++) { > + VFIOMmap *map = region->mmaps + i; > + > + if ((data_offset >= map->offset) && > + (data_offset < map->offset + map->size)) { > + > + /* check if data_offset is within sparse mmap areas */ > + ptr = map->mmap + data_offset - map->offset; > + if (size) { > + *size = MIN(data_size, map->offset + map->size - data_offset); > + } > + break; > + } else if ((data_offset < map->offset) && > + (!limit || limit > map->offset)) { > + /* > + * data_offset is not within sparse mmap areas, find size of > + * non-mapped area. Check through all list since region->mmaps list > + * is not sorted. > + */ > + limit = map->offset; > + } > + } > + > + if (!ptr && size) { > + *size = limit ? MIN(data_size, limit - data_offset) : data_size; > + } > + return ptr; > +} > + > +static int vfio_save_buffer(QEMUFile *f, VFIODevice *vbasedev, uint64_t *size) > +{ > + VFIOMigration *migration = vbasedev->migration; > + VFIORegion *region = &migration->region; > + uint64_t data_offset = 0, data_size = 0, sz; > + int ret; > + > + ret = vfio_mig_read(vbasedev, &data_offset, sizeof(data_offset), > + region->fd_offset + VFIO_MIG_STRUCT_OFFSET(data_offset)); > + if (ret < 0) { > + return ret; > + } > + > + ret = vfio_mig_read(vbasedev, &data_size, sizeof(data_size), > + region->fd_offset + VFIO_MIG_STRUCT_OFFSET(data_size)); > + if (ret < 0) { > + return ret; > + } > + > + trace_vfio_save_buffer(vbasedev->name, data_offset, data_size, > + migration->pending_bytes); > + > + qemu_put_be64(f, data_size); > + sz = data_size; > + > + while (sz) { > + void *buf; > + uint64_t sec_size; > + bool buf_allocated = false; > + > + buf = get_data_section_size(region, data_offset, sz, &sec_size); > + > + if (!buf) { > + buf = g_try_malloc(sec_size); > + if (!buf) { > + error_report("%s: Error allocating buffer ", __func__); > + return -ENOMEM; > + } > + buf_allocated = true; > + > + ret = vfio_mig_read(vbasedev, buf, sec_size, > + region->fd_offset + data_offset); > + if (ret < 0) { > + g_free(buf); > + return ret; > + } > + } > + > + qemu_put_buffer(f, buf, sec_size); > + > + if (buf_allocated) { > + g_free(buf); > + } > + sz -= sec_size; > + data_offset += sec_size; > + } > + > + ret = qemu_file_get_error(f); > + > + if (!ret && size) { > + *size = data_size; > + } > + > + return ret; > +} > + > +static int vfio_update_pending(VFIODevice *vbasedev) > +{ > + VFIOMigration *migration = vbasedev->migration; > + VFIORegion *region = &migration->region; > + uint64_t pending_bytes = 0; > + int ret; > + > + ret = vfio_mig_read(vbasedev, &pending_bytes, sizeof(pending_bytes), > + region->fd_offset + VFIO_MIG_STRUCT_OFFSET(pending_bytes)); > + if (ret < 0) { > + migration->pending_bytes = 0; > + return ret; > + } > + > + migration->pending_bytes = pending_bytes; > + trace_vfio_update_pending(vbasedev->name, pending_bytes); > + return 0; > +} > + > +static int vfio_save_device_config_state(QEMUFile *f, void *opaque) > +{ > + VFIODevice *vbasedev = opaque; > + > + qemu_put_be64(f, VFIO_MIG_FLAG_DEV_CONFIG_STATE); > + > + if (vbasedev->ops && vbasedev->ops->vfio_save_config) { > + vbasedev->ops->vfio_save_config(vbasedev, f); > + } > + > + qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); > + > + trace_vfio_save_device_config_state(vbasedev->name); > + > + return qemu_file_get_error(f); > +} > + > static void vfio_migration_cleanup(VFIODevice *vbasedev) > { > VFIOMigration *migration = vbasedev->migration; > @@ -210,9 +355,140 @@ static void vfio_save_cleanup(void *opaque) > trace_vfio_save_cleanup(vbasedev->name); > } > > +static void vfio_save_pending(QEMUFile *f, void *opaque, > + uint64_t threshold_size, > + uint64_t *res_precopy_only, > + uint64_t *res_compatible, > + uint64_t *res_postcopy_only) > +{ > + VFIODevice *vbasedev = opaque; > + VFIOMigration *migration = vbasedev->migration; > + int ret; > + > + ret = vfio_update_pending(vbasedev); > + if (ret) { > + return; > + } > + > + *res_precopy_only += migration->pending_bytes; > + > + trace_vfio_save_pending(vbasedev->name, *res_precopy_only, > + *res_postcopy_only, *res_compatible); > +} > + > +static int vfio_save_iterate(QEMUFile *f, void *opaque) > +{ > + VFIODevice *vbasedev = opaque; > + VFIOMigration *migration = vbasedev->migration; > + uint64_t data_size; > + int ret; > + > + qemu_put_be64(f, VFIO_MIG_FLAG_DEV_DATA_STATE); > + > + if (migration->pending_bytes == 0) { > + ret = vfio_update_pending(vbasedev); > + if (ret) { > + return ret; > + } > + > + if (migration->pending_bytes == 0) { > + qemu_put_be64(f, 0); > + qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); > + /* indicates data finished, goto complete phase */ > + return 1; > + } > + } > + > + ret = vfio_save_buffer(f, vbasedev, &data_size); > + if (ret) { > + error_report("%s: vfio_save_buffer failed %s", vbasedev->name, > + strerror(errno)); > + return ret; > + } > + > + qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); > + > + ret = qemu_file_get_error(f); > + if (ret) { > + return ret; > + } > + > + /* > + * Reset pending_bytes as .save_live_pending is not called during savevm or > + * snapshot case, in such case vfio_update_pending() at the start of this > + * function updates pending_bytes. > + */ > + migration->pending_bytes = 0; > + trace_vfio_save_iterate(vbasedev->name, data_size); > + return 0; > +} > + > +static int vfio_save_complete_precopy(QEMUFile *f, void *opaque) > +{ > + VFIODevice *vbasedev = opaque; > + VFIOMigration *migration = vbasedev->migration; > + uint64_t data_size; > + int ret; > + > + ret = vfio_migration_set_state(vbasedev, ~VFIO_DEVICE_STATE_RUNNING, > + VFIO_DEVICE_STATE_SAVING); > + if (ret) { > + error_report("%s: Failed to set state STOP and SAVING", > + vbasedev->name); > + return ret; > + } > + > + ret = vfio_save_device_config_state(f, opaque); > + if (ret) { > + return ret; > + } > + > + ret = vfio_update_pending(vbasedev); > + if (ret) { > + return ret; > + } > + > + while (migration->pending_bytes > 0) { > + qemu_put_be64(f, VFIO_MIG_FLAG_DEV_DATA_STATE); > + ret = vfio_save_buffer(f, vbasedev, &data_size); > + if (ret < 0) { > + error_report("%s: Failed to save buffer", vbasedev->name); > + return ret; > + } > + > + if (data_size == 0) { > + break; > + } > + > + ret = vfio_update_pending(vbasedev); > + if (ret) { > + return ret; > + } > + } > + > + qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); > + > + ret = qemu_file_get_error(f); > + if (ret) { > + return ret; > + } > + > + ret = vfio_migration_set_state(vbasedev, ~VFIO_DEVICE_STATE_SAVING, 0); > + if (ret) { > + error_report("%s: Failed to set state STOPPED", vbasedev->name); > + return ret; > + } > + > + trace_vfio_save_complete_precopy(vbasedev->name); > + return ret; > +} > + > static SaveVMHandlers savevm_vfio_handlers = { > .save_setup = vfio_save_setup, > .save_cleanup = vfio_save_cleanup, > + .save_live_pending = vfio_save_pending, > + .save_live_iterate = vfio_save_iterate, > + .save_live_complete_precopy = vfio_save_complete_precopy, > }; > > /* ---------------------------------------------------------------------- */ > diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events > index f148b5e828c1..9f5712dab1ea 100644 > --- a/hw/vfio/trace-events > +++ b/hw/vfio/trace-events > @@ -153,3 +153,9 @@ vfio_vmstate_change(const char *name, int running, const char *reason, uint32_t > vfio_migration_state_notifier(const char *name, const char *state) " (%s) state %s" > vfio_save_setup(const char *name) " (%s)" > vfio_save_cleanup(const char *name) " (%s)" > +vfio_save_buffer(const char *name, uint64_t data_offset, uint64_t data_size, uint64_t pending) " (%s) Offset 0x%"PRIx64" size 0x%"PRIx64" pending 0x%"PRIx64 > +vfio_update_pending(const char *name, uint64_t pending) " (%s) pending 0x%"PRIx64 > +vfio_save_device_config_state(const char *name) " (%s)" > +vfio_save_pending(const char *name, uint64_t precopy, uint64_t postcopy, uint64_t compatible) " (%s) precopy 0x%"PRIx64" postcopy 0x%"PRIx64" compatible 0x%"PRIx64 > +vfio_save_iterate(const char *name, int data_size) " (%s) data_size %d" > +vfio_save_complete_precopy(const char *name) " (%s)" > diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h > index 2bd593ba38bb..f4ebdae013ad 100644 > --- a/include/hw/vfio/vfio-common.h > +++ b/include/hw/vfio/vfio-common.h > @@ -65,6 +65,7 @@ typedef struct VFIOMigration { > uint32_t device_state; > int vm_running; > Notifier migration_state; > + uint64_t pending_bytes; > } VFIOMigration; > > typedef struct VFIOAddressSpace { > -- > 2.7.0 >
diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c index 94d2bdae5c54..be9e4aba541d 100644 --- a/hw/vfio/migration.c +++ b/hw/vfio/migration.c @@ -148,6 +148,151 @@ static int vfio_migration_set_state(VFIODevice *vbasedev, uint32_t mask, return 0; } +static void *get_data_section_size(VFIORegion *region, uint64_t data_offset, + uint64_t data_size, uint64_t *size) +{ + void *ptr = NULL; + uint64_t limit = 0; + int i; + + if (!region->mmaps) { + if (size) { + *size = MIN(data_size, region->size - data_offset); + } + return ptr; + } + + for (i = 0; i < region->nr_mmaps; i++) { + VFIOMmap *map = region->mmaps + i; + + if ((data_offset >= map->offset) && + (data_offset < map->offset + map->size)) { + + /* check if data_offset is within sparse mmap areas */ + ptr = map->mmap + data_offset - map->offset; + if (size) { + *size = MIN(data_size, map->offset + map->size - data_offset); + } + break; + } else if ((data_offset < map->offset) && + (!limit || limit > map->offset)) { + /* + * data_offset is not within sparse mmap areas, find size of + * non-mapped area. Check through all list since region->mmaps list + * is not sorted. + */ + limit = map->offset; + } + } + + if (!ptr && size) { + *size = limit ? MIN(data_size, limit - data_offset) : data_size; + } + return ptr; +} + +static int vfio_save_buffer(QEMUFile *f, VFIODevice *vbasedev, uint64_t *size) +{ + VFIOMigration *migration = vbasedev->migration; + VFIORegion *region = &migration->region; + uint64_t data_offset = 0, data_size = 0, sz; + int ret; + + ret = vfio_mig_read(vbasedev, &data_offset, sizeof(data_offset), + region->fd_offset + VFIO_MIG_STRUCT_OFFSET(data_offset)); + if (ret < 0) { + return ret; + } + + ret = vfio_mig_read(vbasedev, &data_size, sizeof(data_size), + region->fd_offset + VFIO_MIG_STRUCT_OFFSET(data_size)); + if (ret < 0) { + return ret; + } + + trace_vfio_save_buffer(vbasedev->name, data_offset, data_size, + migration->pending_bytes); + + qemu_put_be64(f, data_size); + sz = data_size; + + while (sz) { + void *buf; + uint64_t sec_size; + bool buf_allocated = false; + + buf = get_data_section_size(region, data_offset, sz, &sec_size); + + if (!buf) { + buf = g_try_malloc(sec_size); + if (!buf) { + error_report("%s: Error allocating buffer ", __func__); + return -ENOMEM; + } + buf_allocated = true; + + ret = vfio_mig_read(vbasedev, buf, sec_size, + region->fd_offset + data_offset); + if (ret < 0) { + g_free(buf); + return ret; + } + } + + qemu_put_buffer(f, buf, sec_size); + + if (buf_allocated) { + g_free(buf); + } + sz -= sec_size; + data_offset += sec_size; + } + + ret = qemu_file_get_error(f); + + if (!ret && size) { + *size = data_size; + } + + return ret; +} + +static int vfio_update_pending(VFIODevice *vbasedev) +{ + VFIOMigration *migration = vbasedev->migration; + VFIORegion *region = &migration->region; + uint64_t pending_bytes = 0; + int ret; + + ret = vfio_mig_read(vbasedev, &pending_bytes, sizeof(pending_bytes), + region->fd_offset + VFIO_MIG_STRUCT_OFFSET(pending_bytes)); + if (ret < 0) { + migration->pending_bytes = 0; + return ret; + } + + migration->pending_bytes = pending_bytes; + trace_vfio_update_pending(vbasedev->name, pending_bytes); + return 0; +} + +static int vfio_save_device_config_state(QEMUFile *f, void *opaque) +{ + VFIODevice *vbasedev = opaque; + + qemu_put_be64(f, VFIO_MIG_FLAG_DEV_CONFIG_STATE); + + if (vbasedev->ops && vbasedev->ops->vfio_save_config) { + vbasedev->ops->vfio_save_config(vbasedev, f); + } + + qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); + + trace_vfio_save_device_config_state(vbasedev->name); + + return qemu_file_get_error(f); +} + static void vfio_migration_cleanup(VFIODevice *vbasedev) { VFIOMigration *migration = vbasedev->migration; @@ -210,9 +355,140 @@ static void vfio_save_cleanup(void *opaque) trace_vfio_save_cleanup(vbasedev->name); } +static void vfio_save_pending(QEMUFile *f, void *opaque, + uint64_t threshold_size, + uint64_t *res_precopy_only, + uint64_t *res_compatible, + uint64_t *res_postcopy_only) +{ + VFIODevice *vbasedev = opaque; + VFIOMigration *migration = vbasedev->migration; + int ret; + + ret = vfio_update_pending(vbasedev); + if (ret) { + return; + } + + *res_precopy_only += migration->pending_bytes; + + trace_vfio_save_pending(vbasedev->name, *res_precopy_only, + *res_postcopy_only, *res_compatible); +} + +static int vfio_save_iterate(QEMUFile *f, void *opaque) +{ + VFIODevice *vbasedev = opaque; + VFIOMigration *migration = vbasedev->migration; + uint64_t data_size; + int ret; + + qemu_put_be64(f, VFIO_MIG_FLAG_DEV_DATA_STATE); + + if (migration->pending_bytes == 0) { + ret = vfio_update_pending(vbasedev); + if (ret) { + return ret; + } + + if (migration->pending_bytes == 0) { + qemu_put_be64(f, 0); + qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); + /* indicates data finished, goto complete phase */ + return 1; + } + } + + ret = vfio_save_buffer(f, vbasedev, &data_size); + if (ret) { + error_report("%s: vfio_save_buffer failed %s", vbasedev->name, + strerror(errno)); + return ret; + } + + qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); + + ret = qemu_file_get_error(f); + if (ret) { + return ret; + } + + /* + * Reset pending_bytes as .save_live_pending is not called during savevm or + * snapshot case, in such case vfio_update_pending() at the start of this + * function updates pending_bytes. + */ + migration->pending_bytes = 0; + trace_vfio_save_iterate(vbasedev->name, data_size); + return 0; +} + +static int vfio_save_complete_precopy(QEMUFile *f, void *opaque) +{ + VFIODevice *vbasedev = opaque; + VFIOMigration *migration = vbasedev->migration; + uint64_t data_size; + int ret; + + ret = vfio_migration_set_state(vbasedev, ~VFIO_DEVICE_STATE_RUNNING, + VFIO_DEVICE_STATE_SAVING); + if (ret) { + error_report("%s: Failed to set state STOP and SAVING", + vbasedev->name); + return ret; + } + + ret = vfio_save_device_config_state(f, opaque); + if (ret) { + return ret; + } + + ret = vfio_update_pending(vbasedev); + if (ret) { + return ret; + } + + while (migration->pending_bytes > 0) { + qemu_put_be64(f, VFIO_MIG_FLAG_DEV_DATA_STATE); + ret = vfio_save_buffer(f, vbasedev, &data_size); + if (ret < 0) { + error_report("%s: Failed to save buffer", vbasedev->name); + return ret; + } + + if (data_size == 0) { + break; + } + + ret = vfio_update_pending(vbasedev); + if (ret) { + return ret; + } + } + + qemu_put_be64(f, VFIO_MIG_FLAG_END_OF_STATE); + + ret = qemu_file_get_error(f); + if (ret) { + return ret; + } + + ret = vfio_migration_set_state(vbasedev, ~VFIO_DEVICE_STATE_SAVING, 0); + if (ret) { + error_report("%s: Failed to set state STOPPED", vbasedev->name); + return ret; + } + + trace_vfio_save_complete_precopy(vbasedev->name); + return ret; +} + static SaveVMHandlers savevm_vfio_handlers = { .save_setup = vfio_save_setup, .save_cleanup = vfio_save_cleanup, + .save_live_pending = vfio_save_pending, + .save_live_iterate = vfio_save_iterate, + .save_live_complete_precopy = vfio_save_complete_precopy, }; /* ---------------------------------------------------------------------- */ diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events index f148b5e828c1..9f5712dab1ea 100644 --- a/hw/vfio/trace-events +++ b/hw/vfio/trace-events @@ -153,3 +153,9 @@ vfio_vmstate_change(const char *name, int running, const char *reason, uint32_t vfio_migration_state_notifier(const char *name, const char *state) " (%s) state %s" vfio_save_setup(const char *name) " (%s)" vfio_save_cleanup(const char *name) " (%s)" +vfio_save_buffer(const char *name, uint64_t data_offset, uint64_t data_size, uint64_t pending) " (%s) Offset 0x%"PRIx64" size 0x%"PRIx64" pending 0x%"PRIx64 +vfio_update_pending(const char *name, uint64_t pending) " (%s) pending 0x%"PRIx64 +vfio_save_device_config_state(const char *name) " (%s)" +vfio_save_pending(const char *name, uint64_t precopy, uint64_t postcopy, uint64_t compatible) " (%s) precopy 0x%"PRIx64" postcopy 0x%"PRIx64" compatible 0x%"PRIx64 +vfio_save_iterate(const char *name, int data_size) " (%s) data_size %d" +vfio_save_complete_precopy(const char *name) " (%s)" diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h index 2bd593ba38bb..f4ebdae013ad 100644 --- a/include/hw/vfio/vfio-common.h +++ b/include/hw/vfio/vfio-common.h @@ -65,6 +65,7 @@ typedef struct VFIOMigration { uint32_t device_state; int vm_running; Notifier migration_state; + uint64_t pending_bytes; } VFIOMigration; typedef struct VFIOAddressSpace {