[PATCH qemu v3 3/4] savevm-async: include reason when file open fails

[Erik Fastermann <e.fastermann@proxmox.com>]

blk_new_open() reports why it could not open the file, but the error was
discarded.

Signed-off-by: Erik Fastermann <e.fastermann@proxmox.com>
---
 ...m-async-for-background-state-snapshots.patch | 17 ++++++++++-------
 ...E-add-optional-buffer-size-to-QEMUFile.patch |  6 +++---
 ...euse-migration-blocker-check-for-snaps.patch |  2 +-
 3 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/debian/patches/pve/0017-PVE-add-savevm-async-for-background-state-snapshots.patch b/debian/patches/pve/0017-PVE-add-savevm-async-for-background-state-snapshots.patch
index a4571d8..30400a1 100644
--- a/debian/patches/pve/0017-PVE-add-savevm-async-for-background-state-snapshots.patch
+++ b/debian/patches/pve/0017-PVE-add-savevm-async-for-background-state-snapshots.patch
@@ -39,7 +39,8 @@ Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
 Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
 [EF: drop QIOChannel reference
      free migration vmdesc
-     release resources on start failure path]
+     release resources on start failure path
+     include reason when file open fails]
 Signed-off-by: Erik Fastermann <e.fastermann@proxmox.com>
 ---
  hmp-commands-info.hx         |  13 +
@@ -47,13 +48,13 @@ Signed-off-by: Erik Fastermann <e.fastermann@proxmox.com>
  include/migration/snapshot.h |   2 +
  include/monitor/hmp.h        |   3 +
  migration/meson.build        |   1 +
- migration/savevm-async.c     | 636 +++++++++++++++++++++++++++++++++++
+ migration/savevm-async.c     | 638 +++++++++++++++++++++++++++++++++++
  monitor/hmp-cmds.c           |  38 +++
  qapi/migration.json          |  34 ++
  qapi/misc.json               |  25 ++
  qemu-options.hx              |  12 +
  system/vl.c                  |  10 +
- 11 files changed, 791 insertions(+)
+ 11 files changed, 793 insertions(+)
  create mode 100644 migration/savevm-async.c
 
 diff --git a/hmp-commands-info.hx b/hmp-commands-info.hx
@@ -151,10 +152,10 @@ index 0222d5ea6e..90d62d5723 100644
  ), gnutls, zlib)
 diff --git a/migration/savevm-async.c b/migration/savevm-async.c
 new file mode 100644
-index 0000000000..ef014e93e8
+index 0000000000..bf8509b261
 --- /dev/null
 +++ b/migration/savevm-async.c
-@@ -0,0 +1,636 @@
+@@ -0,0 +1,638 @@
 +#include "qemu/osdep.h"
 +#include "migration/channel-savevm-async.h"
 +#include "migration/migration.h"
@@ -571,7 +572,8 @@ index 0000000000..ef014e93e8
 +    qdict_put_str(options, "driver", "raw");
 +    snap_state.target = blk_new_open(statefile, NULL, options, bdrv_oflags, &local_err);
 +    if (!snap_state.target) {
-+        error_setg(errp, "failed to open '%s'", statefile);
++        error_setg(errp, "failed to open '%s' - %s", statefile,
++                   local_err ? error_get_pretty(local_err) : "unknown error");
 +        goto fail;
 +    }
 +    target_bs = blk_bs(snap_state.target);
@@ -733,7 +735,8 @@ index 0000000000..ef014e93e8
 +    be = blk_new_open(filename, NULL, options, 0, &local_err);
 +
 +    if (!be) {
-+        error_setg(errp, "Could not open VM state file");
++        error_setg(errp, "Could not open VM state file - %s",
++                   local_err ? error_get_pretty(local_err) : "unknown error");
 +        goto the_end;
 +    }
 +
diff --git a/debian/patches/pve/0018-PVE-add-optional-buffer-size-to-QEMUFile.patch b/debian/patches/pve/0018-PVE-add-optional-buffer-size-to-QEMUFile.patch
index 55b3359..caea753 100644
--- a/debian/patches/pve/0018-PVE-add-optional-buffer-size-to-QEMUFile.patch
+++ b/debian/patches/pve/0018-PVE-add-optional-buffer-size-to-QEMUFile.patch
@@ -186,10 +186,10 @@ index a390554208..eda093b16a 100644
  
  G_DEFINE_AUTOPTR_CLEANUP_FUNC(QEMUFile, qemu_fclose)
 diff --git a/migration/savevm-async.c b/migration/savevm-async.c
-index ef014e93e8..f3179b8ad0 100644
+index bf8509b261..94849f5219 100644
 --- a/migration/savevm-async.c
 +++ b/migration/savevm-async.c
-@@ -425,7 +425,7 @@ void qmp_savevm_start(const char *statefile, bool has_skip_vm_start,
+@@ -426,7 +426,7 @@ void qmp_savevm_start(const char *statefile, bool has_skip_vm_start,
  
      QIOChannel *ioc = QIO_CHANNEL(qio_channel_savevm_async_new(snap_state.target,
                                                                 &snap_state.bs_pos));
@@ -198,7 +198,7 @@ index ef014e93e8..f3179b8ad0 100644
      object_unref(ioc);
  
      if (!snap_state.file) {
-@@ -591,7 +591,7 @@ int load_snapshot_from_blockdev(const char *filename, Error **errp)
+@@ -593,7 +593,7 @@ int load_snapshot_from_blockdev(const char *filename, Error **errp)
  
      /* restore the VM state */
      QIOChannel *ioc = QIO_CHANNEL(qio_channel_savevm_async_new(be, &bs_pos));
diff --git a/debian/patches/pve/0046-savevm-async-reuse-migration-blocker-check-for-snaps.patch b/debian/patches/pve/0046-savevm-async-reuse-migration-blocker-check-for-snaps.patch
index 9801a2a..153a569 100644
--- a/debian/patches/pve/0046-savevm-async-reuse-migration-blocker-check-for-snaps.patch
+++ b/debian/patches/pve/0046-savevm-async-reuse-migration-blocker-check-for-snaps.patch
@@ -136,7 +136,7 @@ index b6888daced..80eb0dcd1f 100644
  bool migration_in_postcopy(void);
  bool migration_postcopy_is_alive(MigrationStatus state);
 diff --git a/migration/savevm-async.c b/migration/savevm-async.c
-index f3179b8ad0..41eabea480 100644
+index 94849f5219..4ed5d510bf 100644
 --- a/migration/savevm-async.c
 +++ b/migration/savevm-async.c
 @@ -391,7 +391,7 @@ void qmp_savevm_start(const char *statefile, bool has_skip_vm_start,
-- 
2.47.3