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auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=alex.williamson@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=216.205.24.124; envelope-from=alex.williamson@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/10/22 08:33:10 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: cohuck@redhat.com, cjia@nvidia.com, zhi.wang.linux@gmail.com, aik@ozlabs.ru, Zhengxiao.zx@Alibaba-inc.com, shuangtai.tst@alibaba-inc.com, qemu-devel@nongnu.org, peterx@redhat.com, eauger@redhat.com, yi.l.liu@intel.com, quintela@redhat.com, ziye.yang@intel.com, armbru@redhat.com, mlevitsk@redhat.com, pasic@linux.ibm.com, felipe@nutanix.com, zhi.a.wang@intel.com, mcrossley@nvidia.com, kevin.tian@intel.com, yan.y.zhao@intel.com, dgilbert@redhat.com, changpeng.liu@intel.com, eskultet@redhat.com, Ken.Xue@amd.com, jonathan.davies@nutanix.com, pbonzini@redhat.com, dnigam@nvidia.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Thu, 22 Oct 2020 23:11:39 +0530 Kirti Wankhede wrote: > On 10/22/2020 10:05 PM, Alex Williamson wrote: > > On Thu, 22 Oct 2020 16:41:55 +0530 > > Kirti Wankhede wrote: > > > >> VM state change handler is called on change in VM's state. Based on > >> VM state, VFIO device state should be changed. > >> Added read/write helper functions for migration region. > >> Added function to set device_state. > >> > >> Signed-off-by: Kirti Wankhede > >> Reviewed-by: Neo Jia > >> Reviewed-by: Dr. David Alan Gilbert > >> --- > >> hw/vfio/migration.c | 158 ++++++++++++++++++++++++++++++++++++++++++ > >> hw/vfio/trace-events | 2 + > >> include/hw/vfio/vfio-common.h | 4 ++ > >> 3 files changed, 164 insertions(+) > >> > >> diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c > >> index 5f74a3ad1d72..34f39c7e2e28 100644 > >> --- a/hw/vfio/migration.c > >> +++ b/hw/vfio/migration.c > >> @@ -10,6 +10,7 @@ > >> #include "qemu/osdep.h" > >> #include > >> > >> +#include "sysemu/runstate.h" > >> #include "hw/vfio/vfio-common.h" > >> #include "cpu.h" > >> #include "migration/migration.h" > >> @@ -22,6 +23,157 @@ > >> #include "exec/ram_addr.h" > >> #include "pci.h" > >> #include "trace.h" > >> +#include "hw/hw.h" > >> + > >> +static inline int vfio_mig_access(VFIODevice *vbasedev, void *val, int count, > >> + off_t off, bool iswrite) > >> +{ > >> + int ret; > >> + > >> + ret = iswrite ? pwrite(vbasedev->fd, val, count, off) : > >> + pread(vbasedev->fd, val, count, off); > >> + if (ret < count) { > >> + error_report("vfio_mig_%s %d byte %s: failed at offset 0x%lx, err: %s", > >> + iswrite ? "write" : "read", count, > >> + vbasedev->name, off, strerror(errno)); > >> + return (ret < 0) ? ret : -EINVAL; > >> + } > >> + return 0; > >> +} > >> + > >> +static int vfio_mig_rw(VFIODevice *vbasedev, __u8 *buf, size_t count, > >> + off_t off, bool iswrite) > >> +{ > >> + int ret, done = 0; > >> + __u8 *tbuf = buf; > >> + > >> + while (count) { > >> + int bytes = 0; > >> + > >> + if (count >= 8 && !(off % 8)) { > >> + bytes = 8; > >> + } else if (count >= 4 && !(off % 4)) { > >> + bytes = 4; > >> + } else if (count >= 2 && !(off % 2)) { > >> + bytes = 2; > >> + } else { > >> + bytes = 1; > >> + } > >> + > >> + ret = vfio_mig_access(vbasedev, tbuf, bytes, off, iswrite); > >> + if (ret) { > >> + return ret; > >> + } > >> + > >> + count -= bytes; > >> + done += bytes; > >> + off += bytes; > >> + tbuf += bytes; > >> + } > >> + return done; > >> +} > >> + > >> +#define vfio_mig_read(f, v, c, o) vfio_mig_rw(f, (__u8 *)v, c, o, false) > >> +#define vfio_mig_write(f, v, c, o) vfio_mig_rw(f, (__u8 *)v, c, o, true) > >> + > >> +#define VFIO_MIG_STRUCT_OFFSET(f) \ > >> + offsetof(struct vfio_device_migration_info, f) > >> +/* > >> + * Change the device_state register for device @vbasedev. Bits set in @mask > >> + * are preserved, bits set in @value are set, and bits not set in either @mask > >> + * or @value are cleared in device_state. If the register cannot be accessed, > >> + * the resulting state would be invalid, or the device enters an error state, > >> + * an error is returned. > >> + */ > >> + > >> +static int vfio_migration_set_state(VFIODevice *vbasedev, uint32_t mask, > >> + uint32_t value) > >> +{ > >> + VFIOMigration *migration = vbasedev->migration; > >> + VFIORegion *region = &migration->region; > >> + off_t dev_state_off = region->fd_offset + > >> + VFIO_MIG_STRUCT_OFFSET(device_state); > >> + uint32_t device_state; > >> + int ret; > >> + > >> + ret = vfio_mig_read(vbasedev, &device_state, sizeof(device_state), > >> + dev_state_off); > >> + if (ret < 0) { > >> + return ret; > >> + } > >> + > >> + device_state = (device_state & mask) | value; > >> + > >> + if (!VFIO_DEVICE_STATE_VALID(device_state)) { > >> + return -EINVAL; > >> + } > >> + > >> + ret = vfio_mig_write(vbasedev, &device_state, sizeof(device_state), > >> + dev_state_off); > >> + if (ret < 0) { > >> + int rret; > >> + > >> + rret = vfio_mig_read(vbasedev, &device_state, sizeof(device_state), > >> + dev_state_off); > >> + > >> + if ((rret < 0) || (VFIO_DEVICE_STATE_IS_ERROR(device_state))) { > >> + hw_error("%s: Device in error state 0x%x", vbasedev->name, > >> + device_state); > >> + return rret ? rret : -EIO; > >> + } > >> + return ret; > >> + } > >> + > >> + migration->device_state = device_state; > >> + trace_vfio_migration_set_state(vbasedev->name, device_state); > >> + return 0; > >> +} > >> + > >> +static void vfio_vmstate_change(void *opaque, int running, RunState state) > >> +{ > >> + VFIODevice *vbasedev = opaque; > >> + VFIOMigration *migration = vbasedev->migration; > >> + uint32_t value, mask; > >> + int ret; > >> + > >> + if ((vbasedev->migration->vm_running == running)) { > >> + return; > >> + } > >> + > >> + if (running) { > >> + /* > >> + * Here device state can have one of _SAVING, _RESUMING or _STOP bit. > >> + * Transition from _SAVING to _RUNNING can happen if there is migration > >> + * failure, in that case clear _SAVING bit. > >> + * Transition from _RESUMING to _RUNNING occurs during resuming > >> + * phase, in that case clear _RESUMING bit. > >> + * In both the above cases, set _RUNNING bit. > >> + */ > >> + mask = ~VFIO_DEVICE_STATE_MASK; > >> + value = VFIO_DEVICE_STATE_RUNNING; > >> + } else { > >> + /* > >> + * Here device state could be either _RUNNING or _SAVING|_RUNNING. Reset > >> + * _RUNNING bit > >> + */ > >> + mask = ~VFIO_DEVICE_STATE_RUNNING; > >> + value = 0; > >> + } > >> + > >> + ret = vfio_migration_set_state(vbasedev, mask, value); > >> + if (ret) { > >> + /* > >> + * Migration should be aborted in this case, but vm_state_notify() > >> + * currently does not support reporting failures. > >> + */ > >> + error_report("%s: Failed to set device state 0x%x", vbasedev->name, > >> + (migration->device_state & mask) | value); > >> + qemu_file_set_error(migrate_get_current()->to_dst_file, ret); > >> + } > >> + vbasedev->migration->vm_running = running; > >> + trace_vfio_vmstate_change(vbasedev->name, running, RunState_str(state), > >> + (migration->device_state & mask) | value); > >> +} > >> > >> static void vfio_migration_region_exit(VFIODevice *vbasedev) > >> { > >> @@ -71,6 +223,8 @@ static int vfio_migration_init(VFIODevice *vbasedev, > >> } > >> > >> vbasedev->migration = migration; > >> + migration->vm_state = qemu_add_vm_change_state_handler(vfio_vmstate_change, > >> + vbasedev); > >> return 0; > >> > >> err: > >> @@ -118,6 +272,10 @@ add_blocker: > >> > >> void vfio_migration_finalize(VFIODevice *vbasedev) > >> { > >> + if (vbasedev->migration->vm_state) { > >> + qemu_del_vm_change_state_handler(vbasedev->migration->vm_state); > >> + } > > > > > > This looks like a segfault, vfio_migration_teardown() is eventually > > called unconditionally. The next patch modifies this function further, > > but never checks that vbasedev->migration is non-NULL. Thanks, > > > > Yup. > Updated patch 4, 5 and 6. So now vfio_migration_finalize() looks like: > > void vfio_migration_finalize(VFIODevice *vbasedev) > { > VFIOMigration *migration = vbasedev->migration; > > if (migration) { > if (migration->migration_state.notify) { > > remove_migration_state_change_notifier(&migration->migration_state); > } > > if (migration->vm_state) { > qemu_del_vm_change_state_handler(migration->vm_state); > } We should be able to remove these based only on migration being non-NULL, their setup cannot fail once we've setup the migration pointer. Thanks, Alex > > vfio_migration_region_exit(vbasedev); > g_free(vbasedev->migration); > vbasedev->migration = NULL; > } > > if (vbasedev->migration_blocker) { > migrate_del_blocker(vbasedev->migration_blocker); > error_free(vbasedev->migration_blocker); > vbasedev->migration_blocker = NULL; > } > } > > Thanks, > Kirti > > > Alex > > > > > >> + > >> if (vbasedev->migration_blocker) { > >> migrate_del_blocker(vbasedev->migration_blocker); > >> error_free(vbasedev->migration_blocker); > >> diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events > >> index 9ced5ec6277c..41de81f12f60 100644 > >> --- a/hw/vfio/trace-events > >> +++ b/hw/vfio/trace-events > >> @@ -148,3 +148,5 @@ vfio_display_edid_write_error(void) "" > >> > >> # migration.c > >> vfio_migration_probe(const char *name, uint32_t index) " (%s) Region %d" > >> +vfio_migration_set_state(const char *name, uint32_t state) " (%s) state %d" > >> +vfio_vmstate_change(const char *name, int running, const char *reason, uint32_t dev_state) " (%s) running %d reason %s device state %d" > >> diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h > >> index 8275c4c68f45..9a571f1fb552 100644 > >> --- a/include/hw/vfio/vfio-common.h > >> +++ b/include/hw/vfio/vfio-common.h > >> @@ -29,6 +29,7 @@ > >> #ifdef CONFIG_LINUX > >> #include > >> #endif > >> +#include "sysemu/sysemu.h" > >> > >> #define VFIO_MSG_PREFIX "vfio %s: " > >> > >> @@ -58,7 +59,10 @@ typedef struct VFIORegion { > >> } VFIORegion; > >> > >> typedef struct VFIOMigration { > >> + VMChangeStateEntry *vm_state; > >> VFIORegion region; > >> + uint32_t device_state; > >> + int vm_running; > >> } VFIOMigration; > >> > >> typedef struct VFIOAddressSpace { > > >