From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39618) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gALFb-0002rn-Sz for qemu-devel@nongnu.org; Wed, 10 Oct 2018 16:38:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gALFa-0002V0-P3 for qemu-devel@nongnu.org; Wed, 10 Oct 2018 16:38:35 -0400 From: Aaron Lindsay Date: Wed, 10 Oct 2018 16:37:24 -0400 Message-Id: <20181010203735.27918-4-aclindsa@gmail.com> In-Reply-To: <20181010203735.27918-1-aclindsa@gmail.com> References: <20181010203735.27918-1-aclindsa@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [Qemu-devel] [PATCH v6 03/14] migration: Add post_save function to VMStateDescription List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-arm@nongnu.org, Peter Maydell , Alistair Francis , Wei Huang , Peter Crosthwaite Cc: qemu-devel@nongnu.org, Michael Spradling , Digant Desai , Aaron Lindsay In some cases it may be helpful to modify state before saving it for migration, and then modify the state back after it has been saved. The existing pre_save function provides half of this functionality. This patch adds a post_save function to provide the second half. Signed-off-by: Aaron Lindsay --- docs/devel/migration.rst | 9 +++++++-- include/migration/vmstate.h | 1 + migration/vmstate.c | 10 +++++++++- 3 files changed, 17 insertions(+), 3 deletions(-) diff --git a/docs/devel/migration.rst b/docs/devel/migration.rst index 687570754d..2a2533c9b3 100644 --- a/docs/devel/migration.rst +++ b/docs/devel/migration.rst @@ -419,8 +419,13 @@ The functions to do that are inside a vmstate definition, and are called: This function is called before we save the state of one device. -Example: You can look at hpet.c, that uses the three function to -massage the state that is transferred. +- ``void (*post_save)(void *opaque);`` + + This function is called after we save the state of one device + (even upon failure, unless the call to pre_save returned and error). + +Example: You can look at hpet.c, that uses the first three functions +to massage the state that is transferred. The ``VMSTATE_WITH_TMP`` macro may be useful when the migration data doesn't match the stored device data well; it allows an diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h index 2b501d0466..f6053b94e4 100644 --- a/include/migration/vmstate.h +++ b/include/migration/vmstate.h @@ -185,6 +185,7 @@ struct VMStateDescription { int (*pre_load)(void *opaque); int (*post_load)(void *opaque, int version_id); int (*pre_save)(void *opaque); + void (*post_save)(void *opaque); bool (*needed)(void *opaque); VMStateField *fields; const VMStateDescription **subsections; diff --git a/migration/vmstate.c b/migration/vmstate.c index 0bc240a317..9afc9298f3 100644 --- a/migration/vmstate.c +++ b/migration/vmstate.c @@ -387,6 +387,9 @@ int vmstate_save_state_v(QEMUFile *f, const VMStateDescription *vmsd, if (ret) { error_report("Save of field %s/%s failed", vmsd->name, field->name); + if (vmsd->post_save) { + vmsd->post_save(opaque); + } return ret; } @@ -412,7 +415,12 @@ int vmstate_save_state_v(QEMUFile *f, const VMStateDescription *vmsd, json_end_array(vmdesc); } - return vmstate_subsection_save(f, vmsd, opaque, vmdesc); + ret = vmstate_subsection_save(f, vmsd, opaque, vmdesc); + + if (vmsd->post_save) { + vmsd->post_save(opaque); + } + return ret; } static const VMStateDescription * -- 2.19.1