From 56a60bd1b230c86195778e4fda2f44052faae10c Mon Sep 17 00:00:00 2001

Message-Id: <56a60bd1b230c86195778e4fda2f44052faae10c@dist-git>

From: Jiri Denemark <jdenemar@redhat.com>

Date: Wed, 7 Jun 2017 00:08:25 +0200

Subject: [PATCH] qemu: Introduce virQEMUSaveData structure

The new structure encapsulates save image header and associated data

(domain XML).

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>

Reviewed-by: Pavel Hrdina <phrdina@redhat.com>

(cherry picked from commit 47e60ac306273559b8c14527ea15a92c6ac6dd91)

https://bugzilla.redhat.com/show_bug.cgi?id=1441662

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>

---

 src/qemu/qemu_driver.c | 165 ++++++++++++++++++++++++++-----------------------

 1 file changed, 86 insertions(+), 79 deletions(-)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c

index 1629f27470..7ce0f01f70 100644

--- a/src/qemu/qemu_driver.c

+++ b/src/qemu/qemu_driver.c

@@ -2816,6 +2816,14 @@ struct _virQEMUSaveHeader {

     uint32_t unused[15];

 };

+typedef struct _virQEMUSaveData virQEMUSaveData;

+typedef virQEMUSaveData *virQEMUSaveDataPtr;

+struct _virQEMUSaveData {

+    virQEMUSaveHeader header;

+    char *xml;

+};

+

+

 static inline void

 bswap_header(virQEMUSaveHeaderPtr hdr)

 {

@@ -2827,31 +2835,39 @@ bswap_header(virQEMUSaveHeaderPtr hdr)

 static void

-virQEMUSaveDataFree(virQEMUSaveHeaderPtr header)

+virQEMUSaveDataFree(virQEMUSaveDataPtr data)

 {

-    if (!header)

+    if (!data)

         return;

-    VIR_FREE(header);

+    VIR_FREE(data->xml);

+    VIR_FREE(data);

 }

-static virQEMUSaveHeaderPtr

-virQEMUSaveDataNew(char *domXML ATTRIBUTE_UNUSED,

+/**

+ * This function steals @domXML on success.

+ */

+static virQEMUSaveDataPtr

+virQEMUSaveDataNew(char *domXML,

                    bool running,

                    int compressed)

 {

-    virQEMUSaveHeaderPtr header = NULL;

+    virQEMUSaveDataPtr data = NULL;

+    virQEMUSaveHeaderPtr header;

-    if (VIR_ALLOC(header) < 0)

+    if (VIR_ALLOC(data) < 0)

         return NULL;

+    VIR_STEAL_PTR(data->xml, domXML);

+

+    header = &data->header;

     memcpy(header->magic, QEMU_SAVE_PARTIAL, sizeof(header->magic));

     header->version = QEMU_SAVE_VERSION;

     header->was_running = running ? 1 : 0;

     header->compressed = compressed;

-    return header;

+    return data;

 }

@@ -2865,17 +2881,17 @@ virQEMUSaveDataNew(char *domXML ATTRIBUTE_UNUSED,

  * Returns -1 on failure, or 0 on success.

  */

 static int

-virQEMUSaveDataWrite(virQEMUSaveHeaderPtr header,

-                     const char *xml,

+virQEMUSaveDataWrite(virQEMUSaveDataPtr data,

                      int fd,

                      const char *path)

 {

+    virQEMUSaveHeaderPtr header = &data->header;

     size_t len;

     int ret = -1;

     size_t zerosLen = 0;

     char *zeros = NULL;

-    len = strlen(xml) + 1;

+    len = strlen(data->xml) + 1;

     if (header->data_len > 0) {

         if (len > header->data_len) {

@@ -2898,7 +2914,7 @@ virQEMUSaveDataWrite(virQEMUSaveHeaderPtr header,

         goto cleanup;

     }

-    if (safewrite(fd, xml, header->data_len) != header->data_len ||

+    if (safewrite(fd, data->xml, header->data_len) != header->data_len ||

         safewrite(fd, zeros, zerosLen) != zerosLen) {

         virReportSystemError(errno,

                              _("failed to write domain xml to '%s'"),

@@ -2915,10 +2931,12 @@ virQEMUSaveDataWrite(virQEMUSaveHeaderPtr header,

 static int

-virQEMUSaveDataFinish(virQEMUSaveHeaderPtr header,

+virQEMUSaveDataFinish(virQEMUSaveDataPtr data,

                       int *fd,

                       const char *path)

 {

+    virQEMUSaveHeaderPtr header = &data->header;

+

     memcpy(header->magic, QEMU_SAVE_MAGIC, sizeof(header->magic));

     if (safewrite(*fd, header, sizeof(*header)) != sizeof(*header) ||

@@ -3128,8 +3146,7 @@ static int

 qemuDomainSaveMemory(virQEMUDriverPtr driver,

                      virDomainObjPtr vm,

                      const char *path,

-                     const char *domXML,

-                     virQEMUSaveHeaderPtr header,

+                     virQEMUSaveDataPtr data,

                      const char *compressedpath,

                      unsigned int flags,

                      qemuDomainAsyncJob asyncJob)

@@ -3164,7 +3181,7 @@ qemuDomainSaveMemory(virQEMUDriverPtr driver,

     if (!(wrapperFd = virFileWrapperFdNew(&fd, path, wrapperFlags)))

         goto cleanup;

-    if (virQEMUSaveDataWrite(header, domXML, fd, path) < 0)

+    if (virQEMUSaveDataWrite(data, fd, path) < 0)

         goto cleanup;

     /* Perform the migration */

@@ -3186,7 +3203,7 @@ qemuDomainSaveMemory(virQEMUDriverPtr driver,

         goto cleanup;

     if ((fd = qemuOpenFile(driver, vm, path, O_WRONLY, NULL, NULL)) < 0 ||

-        virQEMUSaveDataFinish(header, &fd, path) < 0)

+        virQEMUSaveDataFinish(data, &fd, path) < 0)

         goto cleanup;

     ret = 0;

@@ -3218,7 +3235,7 @@ qemuDomainSaveInternal(virQEMUDriverPtr driver, virDomainPtr dom,

     virObjectEventPtr event = NULL;

     qemuDomainObjPrivatePtr priv = vm->privateData;

     virCapsPtr caps;

-    virQEMUSaveHeaderPtr header = NULL;

+    virQEMUSaveDataPtr data = NULL;

     if (!(caps = virQEMUDriverGetCapabilities(driver, false)))

         goto cleanup;

@@ -3284,10 +3301,11 @@ qemuDomainSaveInternal(virQEMUDriverPtr driver, virDomainPtr dom,

         goto endjob;

     }

-    if (!(header = virQEMUSaveDataNew(xml, was_running, compressed)))

+    if (!(data = virQEMUSaveDataNew(xml, was_running, compressed)))

         goto endjob;

+    xml = NULL;

-    ret = qemuDomainSaveMemory(driver, vm, path, xml, header, compressedpath,

+    ret = qemuDomainSaveMemory(driver, vm, path, data, compressedpath,

                                flags, QEMU_ASYNC_JOB_SAVE);

     if (ret < 0)

         goto endjob;

@@ -3321,7 +3339,7 @@ qemuDomainSaveInternal(virQEMUDriverPtr driver, virDomainPtr dom,

  cleanup:

     VIR_FREE(xml);

-    virQEMUSaveDataFree(header);

+    virQEMUSaveDataFree(data);

     qemuDomainEventQueue(driver, event);

     virObjectUnref(caps);

     return ret;

@@ -6238,8 +6256,7 @@ qemuDomainSaveImageUpdateDef(virQEMUDriverPtr driver,

  * @driver: qemu driver data

  * @path: path of the save image

  * @ret_def: returns domain definition created from the XML stored in the image

- * @ret_header: returns structure filled with data from the image header

- * @xmlout: returns the XML from the image file (may be NULL)

+ * @ret_data: returns structure filled with data from the image header

  * @bypass_cache: bypass cache when opening the file

  * @wrapperFd: returns the file wrapper structure

  * @open_write: open the file for writing (for updates)

@@ -6253,16 +6270,15 @@ static int ATTRIBUTE_NONNULL(3) ATTRIBUTE_NONNULL(4)

 qemuDomainSaveImageOpen(virQEMUDriverPtr driver,

                         const char *path,

                         virDomainDefPtr *ret_def,

-                        virQEMUSaveHeaderPtr *ret_header,

-                        char **xmlout,

+                        virQEMUSaveDataPtr *ret_data,

                         bool bypass_cache,

                         virFileWrapperFdPtr *wrapperFd,

                         bool open_write,

                         bool unlink_corrupt)

 {

     int fd = -1;

-    char *xml = NULL;

-    virQEMUSaveHeaderPtr header = NULL;

+    virQEMUSaveDataPtr data = NULL;

+    virQEMUSaveHeaderPtr header;

     virDomainDefPtr def = NULL;

     int oflags = open_write ? O_RDWR : O_RDONLY;

     virCapsPtr caps = NULL;

@@ -6287,9 +6303,10 @@ qemuDomainSaveImageOpen(virQEMUDriverPtr driver,

                                            VIR_FILE_WRAPPER_BYPASS_CACHE)))

         goto error;

-    if (VIR_ALLOC(header) < 0)

+    if (VIR_ALLOC(data) < 0)

         goto error;

+    header = &data->header;

     if (saferead(fd, header, sizeof(*header)) != sizeof(*header)) {

         if (unlink_corrupt) {

             if (VIR_CLOSE(fd) < 0 || unlink(path) < 0) {

@@ -6341,32 +6358,27 @@ qemuDomainSaveImageOpen(virQEMUDriverPtr driver,

     if (header->data_len <= 0) {

         virReportError(VIR_ERR_OPERATION_FAILED,

-                       _("invalid XML length: %d"), header->data_len);

+                       _("invalid header data length: %d"), header->data_len);

         goto error;

     }

-    if (VIR_ALLOC_N(xml, header->data_len) < 0)

+    if (VIR_ALLOC_N(data->xml, header->data_len) < 0)

         goto error;

-    if (saferead(fd, xml, header->data_len) != header->data_len) {

+    if (saferead(fd, data->xml, header->data_len) != header->data_len) {

         virReportError(VIR_ERR_OPERATION_FAILED,

-                       "%s", _("failed to read XML"));

+                       "%s", _("failed to read domain XML"));

         goto error;

     }

     /* Create a domain from this XML */

-    if (!(def = virDomainDefParseString(xml, caps, driver->xmlopt, NULL,

+    if (!(def = virDomainDefParseString(data->xml, caps, driver->xmlopt, NULL,

                                         VIR_DOMAIN_DEF_PARSE_INACTIVE |

                                         VIR_DOMAIN_DEF_PARSE_SKIP_VALIDATE)))

         goto error;

-    if (xmlout)

-        *xmlout = xml;

-    else

-        VIR_FREE(xml);

-

     *ret_def = def;

-    *ret_header = header;

+    *ret_data = data;

     virObjectUnref(caps);

@@ -6374,8 +6386,7 @@ qemuDomainSaveImageOpen(virQEMUDriverPtr driver,

  error:

     virDomainDefFree(def);

-    VIR_FREE(xml);

-    virQEMUSaveDataFree(header);

+    virQEMUSaveDataFree(data);

     VIR_FORCE_CLOSE(fd);

     virObjectUnref(caps);

@@ -6387,7 +6398,7 @@ qemuDomainSaveImageStartVM(virConnectPtr conn,

                            virQEMUDriverPtr driver,

                            virDomainObjPtr vm,

                            int *fd,

-                           virQEMUSaveHeaderPtr header,

+                           virQEMUSaveDataPtr data,

                            const char *path,

                            bool start_paused,

                            qemuDomainAsyncJob asyncJob)

@@ -6399,6 +6410,7 @@ qemuDomainSaveImageStartVM(virConnectPtr conn,

     virCommandPtr cmd = NULL;

     char *errbuf = NULL;

     virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);

+    virQEMUSaveHeaderPtr header = &data->header;

     if ((header->version == 2) &&

         (header->compressed != QEMU_SAVE_FORMAT_RAW)) {

@@ -6508,12 +6520,11 @@ qemuDomainRestoreFlags(virConnectPtr conn,

     qemuDomainObjPrivatePtr priv = NULL;

     virDomainDefPtr def = NULL;

     virDomainObjPtr vm = NULL;

-    char *xml = NULL;

     char *xmlout = NULL;

     const char *newxml = dxml;

     int fd = -1;

     int ret = -1;

-    virQEMUSaveHeaderPtr header = NULL;

+    virQEMUSaveDataPtr data = NULL;

     virFileWrapperFdPtr wrapperFd = NULL;

     bool hook_taint = false;

@@ -6524,7 +6535,7 @@ qemuDomainRestoreFlags(virConnectPtr conn,

     virNWFilterReadLockFilterUpdates();

-    fd = qemuDomainSaveImageOpen(driver, path, &def, &header, &xml,

+    fd = qemuDomainSaveImageOpen(driver, path, &def, &data,

                                  (flags & VIR_DOMAIN_SAVE_BYPASS_CACHE) != 0,

                                  &wrapperFd, false, false);

     if (fd < 0)

@@ -6540,7 +6551,7 @@ qemuDomainRestoreFlags(virConnectPtr conn,

                                    VIR_HOOK_QEMU_OP_RESTORE,

                                    VIR_HOOK_SUBOP_BEGIN,

                                    NULL,

-                                   dxml ? dxml : xml,

+                                   dxml ? dxml : data->xml,

                                    &xmlout)) < 0)

             goto cleanup;

@@ -6570,9 +6581,9 @@ qemuDomainRestoreFlags(virConnectPtr conn,

     def = NULL;

     if (flags & VIR_DOMAIN_SAVE_RUNNING)

-        header->was_running = 1;

+        data->header.was_running = 1;

     else if (flags & VIR_DOMAIN_SAVE_PAUSED)

-        header->was_running = 0;

+        data->header.was_running = 0;

     if (hook_taint) {

         priv = vm->privateData;

@@ -6582,7 +6593,7 @@ qemuDomainRestoreFlags(virConnectPtr conn,

     if (qemuProcessBeginJob(driver, vm, VIR_DOMAIN_JOB_OPERATION_RESTORE) < 0)

         goto cleanup;

-    ret = qemuDomainSaveImageStartVM(conn, driver, vm, &fd, header, path,

+    ret = qemuDomainSaveImageStartVM(conn, driver, vm, &fd, data, path,

                                      false, QEMU_ASYNC_JOB_START);

     if (virFileWrapperFdClose(wrapperFd) < 0)

         VIR_WARN("Failed to close %s", path);

@@ -6592,8 +6603,7 @@ qemuDomainRestoreFlags(virConnectPtr conn,

  cleanup:

     virDomainDefFree(def);

     VIR_FORCE_CLOSE(fd);

-    VIR_FREE(xml);

-    virQEMUSaveDataFree(header);

+    virQEMUSaveDataFree(data);

     VIR_FREE(xmlout);

     virFileWrapperFdFree(wrapperFd);

     if (vm && ret < 0)

@@ -6618,12 +6628,12 @@ qemuDomainSaveImageGetXMLDesc(virConnectPtr conn, const char *path,

     char *ret = NULL;

     virDomainDefPtr def = NULL;

     int fd = -1;

-    virQEMUSaveHeaderPtr header = NULL;

+    virQEMUSaveDataPtr data = NULL;

     /* We only take subset of virDomainDefFormat flags.  */

     virCheckFlags(VIR_DOMAIN_XML_SECURE, NULL);

-    fd = qemuDomainSaveImageOpen(driver, path, &def, &header, NULL,

+    fd = qemuDomainSaveImageOpen(driver, path, &def, &data,

                                  false, NULL, false, false);

     if (fd < 0)

@@ -6635,7 +6645,7 @@ qemuDomainSaveImageGetXMLDesc(virConnectPtr conn, const char *path,

     ret = qemuDomainDefFormatXML(driver, def, flags);

  cleanup:

-    virQEMUSaveDataFree(header);

+    virQEMUSaveDataFree(data);

     virDomainDefFree(def);

     VIR_FORCE_CLOSE(fd);

     return ret;

@@ -6650,8 +6660,7 @@ qemuDomainSaveImageDefineXML(virConnectPtr conn, const char *path,

     virDomainDefPtr def = NULL;

     virDomainDefPtr newdef = NULL;

     int fd = -1;

-    char *xml = NULL;

-    virQEMUSaveHeaderPtr header = NULL;

+    virQEMUSaveDataPtr data = NULL;

     int state = -1;

     virCheckFlags(VIR_DOMAIN_SAVE_RUNNING |

@@ -6662,7 +6671,7 @@ qemuDomainSaveImageDefineXML(virConnectPtr conn, const char *path,

     else if (flags & VIR_DOMAIN_SAVE_PAUSED)

         state = 0;

-    fd = qemuDomainSaveImageOpen(driver, path, &def, &header, &xml,

+    fd = qemuDomainSaveImageOpen(driver, path, &def, &data,

                                  false, NULL, true, false);

     if (fd < 0)

@@ -6671,25 +6680,25 @@ qemuDomainSaveImageDefineXML(virConnectPtr conn, const char *path,

     if (virDomainSaveImageDefineXMLEnsureACL(conn, def) < 0)

         goto cleanup;

-    if (STREQ(xml, dxml) &&

-        (state < 0 || state == header->was_running)) {

+    if (STREQ(data->xml, dxml) &&

+        (state < 0 || state == data->header.was_running)) {

         /* no change to the XML */

         ret = 0;

         goto cleanup;

     }

     if (state >= 0)

-        header->was_running = state;

+        data->header.was_running = state;

     if (!(newdef = qemuDomainSaveImageUpdateDef(driver, def, dxml)))

         goto cleanup;

-    VIR_FREE(xml);

+    VIR_FREE(data->xml);

-    if (!(xml = qemuDomainDefFormatXML(driver, newdef,

-                                       VIR_DOMAIN_XML_INACTIVE |

-                                       VIR_DOMAIN_XML_SECURE |

-                                       VIR_DOMAIN_XML_MIGRATABLE)))

+    if (!(data->xml = qemuDomainDefFormatXML(driver, newdef,

+                                             VIR_DOMAIN_XML_INACTIVE |

+                                             VIR_DOMAIN_XML_SECURE |

+                                             VIR_DOMAIN_XML_MIGRATABLE)))

         goto cleanup;

     if (lseek(fd, 0, SEEK_SET) != 0) {

@@ -6697,7 +6706,7 @@ qemuDomainSaveImageDefineXML(virConnectPtr conn, const char *path,

         goto cleanup;

     }

-    if (virQEMUSaveDataWrite(header, xml, fd, path) < 0)

+    if (virQEMUSaveDataWrite(data, fd, path) < 0)

         goto cleanup;

     if (VIR_CLOSE(fd) < 0) {

@@ -6711,8 +6720,7 @@ qemuDomainSaveImageDefineXML(virConnectPtr conn, const char *path,

     virDomainDefFree(def);

     virDomainDefFree(newdef);

     VIR_FORCE_CLOSE(fd);

-    VIR_FREE(xml);

-    virQEMUSaveDataFree(header);

+    virQEMUSaveDataFree(data);

     return ret;

 }

@@ -6731,12 +6739,11 @@ qemuDomainObjRestore(virConnectPtr conn,

     qemuDomainObjPrivatePtr priv = vm->privateData;

     int fd = -1;

     int ret = -1;

-    char *xml = NULL;

     char *xmlout = NULL;

-    virQEMUSaveHeaderPtr header = NULL;

+    virQEMUSaveDataPtr data = NULL;

     virFileWrapperFdPtr wrapperFd = NULL;

-    fd = qemuDomainSaveImageOpen(driver, path, &def, &header, &xml,

+    fd = qemuDomainSaveImageOpen(driver, path, &def, &data,

                                  bypass_cache, &wrapperFd, false, true);

     if (fd < 0) {

         if (fd == -3)

@@ -6750,7 +6757,7 @@ qemuDomainObjRestore(virConnectPtr conn,

         if ((hookret = virHookCall(VIR_HOOK_DRIVER_QEMU, def->name,

                                    VIR_HOOK_QEMU_OP_RESTORE,

                                    VIR_HOOK_SUBOP_BEGIN,

-                                   NULL, xml, &xmlout)) < 0)

+                                   NULL, data->xml, &xmlout)) < 0)

             goto cleanup;

         if (hookret == 0 && !virStringIsEmpty(xmlout)) {

@@ -6784,14 +6791,13 @@ qemuDomainObjRestore(virConnectPtr conn,

     virDomainObjAssignDef(vm, def, true, NULL);

     def = NULL;

-    ret = qemuDomainSaveImageStartVM(conn, driver, vm, &fd, header, path,

+    ret = qemuDomainSaveImageStartVM(conn, driver, vm, &fd, data, path,

                                      start_paused, asyncJob);

     if (virFileWrapperFdClose(wrapperFd) < 0)

         VIR_WARN("Failed to close %s", path);

  cleanup:

-    VIR_FREE(xml);

-    virQEMUSaveDataFree(header);

+    virQEMUSaveDataFree(data);

     VIR_FREE(xmlout);

     virDomainDefFree(def);

     VIR_FORCE_CLOSE(fd);

@@ -14364,7 +14370,7 @@ qemuDomainSnapshotCreateActiveExternal(virConnectPtr conn,

     virQEMUDriverConfigPtr cfg = NULL;

     int compressed;

     char *compressedpath = NULL;

-    virQEMUSaveHeaderPtr header = NULL;

+    virQEMUSaveDataPtr data = NULL;

     /* If quiesce was requested, then issue a freeze command, and a

      * counterpart thaw command when it is actually sent to agent.

@@ -14436,10 +14442,11 @@ qemuDomainSnapshotCreateActiveExternal(virConnectPtr conn,

         if (!(xml = qemuDomainDefFormatLive(driver, vm->def, true, true)))

             goto cleanup;

-        if (!(header = virQEMUSaveDataNew(xml, resume, compressed)))

+        if (!(data = virQEMUSaveDataNew(xml, resume, compressed)))

             goto cleanup;

+        xml = NULL;

-        if ((ret = qemuDomainSaveMemory(driver, vm, snap->def->file, xml, header,

+        if ((ret = qemuDomainSaveMemory(driver, vm, snap->def->file, data,

                                         compressedpath, 0,

                                         QEMU_ASYNC_JOB_SNAPSHOT)) < 0)

             goto cleanup;

@@ -14509,7 +14516,7 @@ qemuDomainSnapshotCreateActiveExternal(virConnectPtr conn,

             ret = -1;

     }

-    virQEMUSaveDataFree(header);

+    virQEMUSaveDataFree(data);

     VIR_FREE(xml);

     VIR_FREE(compressedpath);

     virObjectUnref(cfg);

-- 

2.13.1