[PATCH 4/5] qemu: Split of code related to handling of the save image file
Peter Krempa
pkrempa at redhat.com
Thu Aug 6 09:55:15 UTC 2020
There's a lot of helper code related to the save image handling. Extract
it to qemu_saveimage.c/h.
Signed-off-by: Peter Krempa <pkrempa at redhat.com>
---
po/POTFILES.in | 1 +
src/qemu/meson.build | 1 +
src/qemu/qemu_driver.c | 843 +++-----------------------------------
src/qemu/qemu_saveimage.c | 764 ++++++++++++++++++++++++++++++++++
src/qemu/qemu_saveimage.h | 116 ++++++
5 files changed, 928 insertions(+), 797 deletions(-)
create mode 100644 src/qemu/qemu_saveimage.c
create mode 100644 src/qemu/qemu_saveimage.h
diff --git a/po/POTFILES.in b/po/POTFILES.in
index c5b43df7b5..6f47371b01 100644
--- a/po/POTFILES.in
+++ b/po/POTFILES.in
@@ -170,6 +170,7 @@
@SRCDIR at src/qemu/qemu_namespace.c
@SRCDIR at src/qemu/qemu_process.c
@SRCDIR at src/qemu/qemu_qapi.c
+ at SRCDIR@src/qemu/qemu_saveimage.c
@SRCDIR at src/qemu/qemu_slirp.c
@SRCDIR at src/qemu/qemu_tpm.c
@SRCDIR at src/qemu/qemu_validate.c
diff --git a/src/qemu/meson.build b/src/qemu/meson.build
index 7faba16049..7d5249978a 100644
--- a/src/qemu/meson.build
+++ b/src/qemu/meson.build
@@ -29,6 +29,7 @@ qemu_driver_sources = [
'qemu_namespace.c',
'qemu_process.c',
'qemu_qapi.c',
+ 'qemu_saveimage.c',
'qemu_security.c',
'qemu_slirp.c',
'qemu_tpm.c',
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 8f61759f53..a6b8c79168 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -51,6 +51,7 @@
#include "qemu_checkpoint.h"
#include "qemu_backup.h"
#include "qemu_namespace.h"
+#include "qemu_saveimage.h"
#include "virerror.h"
#include "virlog.h"
@@ -135,6 +136,16 @@ VIR_LOG_INIT("qemu.qemu_driver");
#define QEMU_NB_BANDWIDTH_PARAM 7
+VIR_ENUM_DECL(qemuDumpFormat);
+VIR_ENUM_IMPL(qemuDumpFormat,
+ VIR_DOMAIN_CORE_DUMP_FORMAT_LAST,
+ "elf",
+ "kdump-zlib",
+ "kdump-lzo",
+ "kdump-snappy",
+);
+
+
static void qemuProcessEventHandler(void *data, void *opaque);
static int qemuStateCleanup(void);
@@ -2771,339 +2782,6 @@ qemuDomainGetControlInfo(virDomainPtr dom,
}
-/* It would be nice to replace 'Qemud' with 'Qemu' but
- * this magic string is ABI, so it can't be changed
- */
-#define QEMU_SAVE_MAGIC "LibvirtQemudSave"
-#define QEMU_SAVE_PARTIAL "LibvirtQemudPart"
-#define QEMU_SAVE_VERSION 2
-
-G_STATIC_ASSERT(sizeof(QEMU_SAVE_MAGIC) == sizeof(QEMU_SAVE_PARTIAL));
-
-typedef enum {
- QEMU_SAVE_FORMAT_RAW = 0,
- QEMU_SAVE_FORMAT_GZIP = 1,
- QEMU_SAVE_FORMAT_BZIP2 = 2,
- /*
- * Deprecated by xz and never used as part of a release
- * QEMU_SAVE_FORMAT_LZMA
- */
- QEMU_SAVE_FORMAT_XZ = 3,
- QEMU_SAVE_FORMAT_LZOP = 4,
- /* Note: add new members only at the end.
- These values are used in the on-disk format.
- Do not change or re-use numbers. */
-
- QEMU_SAVE_FORMAT_LAST
-} virQEMUSaveFormat;
-
-VIR_ENUM_DECL(qemuSaveCompression);
-VIR_ENUM_IMPL(qemuSaveCompression,
- QEMU_SAVE_FORMAT_LAST,
- "raw",
- "gzip",
- "bzip2",
- "xz",
- "lzop",
-);
-
-VIR_ENUM_DECL(qemuDumpFormat);
-VIR_ENUM_IMPL(qemuDumpFormat,
- VIR_DOMAIN_CORE_DUMP_FORMAT_LAST,
- "elf",
- "kdump-zlib",
- "kdump-lzo",
- "kdump-snappy",
-);
-
-typedef struct _virQEMUSaveHeader virQEMUSaveHeader;
-typedef virQEMUSaveHeader *virQEMUSaveHeaderPtr;
-struct _virQEMUSaveHeader {
- char magic[sizeof(QEMU_SAVE_MAGIC)-1];
- uint32_t version;
- uint32_t data_len;
- uint32_t was_running;
- uint32_t compressed;
- uint32_t cookieOffset;
- uint32_t unused[14];
-};
-
-typedef struct _virQEMUSaveData virQEMUSaveData;
-typedef virQEMUSaveData *virQEMUSaveDataPtr;
-struct _virQEMUSaveData {
- virQEMUSaveHeader header;
- char *xml;
- char *cookie;
-};
-
-
-static inline void
-bswap_header(virQEMUSaveHeaderPtr hdr)
-{
- hdr->version = GUINT32_SWAP_LE_BE(hdr->version);
- hdr->data_len = GUINT32_SWAP_LE_BE(hdr->data_len);
- hdr->was_running = GUINT32_SWAP_LE_BE(hdr->was_running);
- hdr->compressed = GUINT32_SWAP_LE_BE(hdr->compressed);
- hdr->cookieOffset = GUINT32_SWAP_LE_BE(hdr->cookieOffset);
-}
-
-
-static void
-virQEMUSaveDataFree(virQEMUSaveDataPtr data)
-{
- if (!data)
- return;
-
- VIR_FREE(data->xml);
- VIR_FREE(data->cookie);
- VIR_FREE(data);
-}
-
-G_DEFINE_AUTOPTR_CLEANUP_FUNC(virQEMUSaveData, virQEMUSaveDataFree);
-
-/**
- * This function steals @domXML on success.
- */
-static virQEMUSaveDataPtr
-virQEMUSaveDataNew(char *domXML,
- qemuDomainSaveCookiePtr cookieObj,
- bool running,
- int compressed,
- virDomainXMLOptionPtr xmlopt)
-{
- virQEMUSaveDataPtr data = NULL;
- virQEMUSaveHeaderPtr header;
-
- if (VIR_ALLOC(data) < 0)
- return NULL;
-
- data->xml = g_steal_pointer(&domXML);
-
- if (cookieObj &&
- !(data->cookie = virSaveCookieFormat((virObjectPtr) cookieObj,
- virDomainXMLOptionGetSaveCookie(xmlopt))))
- goto error;
-
- 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 data;
-
- error:
- virQEMUSaveDataFree(data);
- return NULL;
-}
-
-
-/* virQEMUSaveDataWrite:
- *
- * Writes libvirt's header (including domain XML) into a saved image of a
- * running domain. If @header has data_len filled in (because it was previously
- * read from the file), the function will make sure the new data will fit
- * within data_len.
- *
- * Returns -1 on failure, or 0 on success.
- */
-static int
-virQEMUSaveDataWrite(virQEMUSaveDataPtr data,
- int fd,
- const char *path)
-{
- virQEMUSaveHeaderPtr header = &data->header;
- size_t len;
- size_t xml_len;
- size_t cookie_len = 0;
- size_t zerosLen = 0;
- g_autofree char *zeros = NULL;
-
- xml_len = strlen(data->xml) + 1;
- if (data->cookie)
- cookie_len = strlen(data->cookie) + 1;
-
- len = xml_len + cookie_len;
-
- if (header->data_len == 0) {
- /* This 64kb padding allows the user to edit the XML in
- * a saved state image and have the new XML be larger
- * that what was originally saved
- */
- header->data_len = len + (64 * 1024);
- } else {
- if (len > header->data_len) {
- virReportError(VIR_ERR_OPERATION_FAILED, "%s",
- _("new xml too large to fit in file"));
- return -1;
- }
- }
-
- zerosLen = header->data_len - len;
- zeros = g_new0(char, zerosLen);
-
- if (data->cookie)
- header->cookieOffset = xml_len;
-
- if (safewrite(fd, header, sizeof(*header)) != sizeof(*header)) {
- virReportSystemError(errno,
- _("failed to write header to domain save file '%s'"),
- path);
- return -1;
- }
-
- if (safewrite(fd, data->xml, xml_len) != xml_len) {
- virReportSystemError(errno,
- _("failed to write domain xml to '%s'"),
- path);
- return -1;
- }
-
- if (data->cookie &&
- safewrite(fd, data->cookie, cookie_len) != cookie_len) {
- virReportSystemError(errno,
- _("failed to write cookie to '%s'"),
- path);
- return -1;
- }
-
- if (safewrite(fd, zeros, zerosLen) != zerosLen) {
- virReportSystemError(errno,
- _("failed to write padding to '%s'"),
- path);
- return -1;
- }
-
- return 0;
-}
-
-
-static int
-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) ||
- VIR_CLOSE(*fd) < 0) {
- virReportSystemError(errno,
- _("failed to write header to domain save file '%s'"),
- path);
- return -1;
- }
-
- return 0;
-}
-
-
-static virCommandPtr
-qemuCompressGetCommand(virQEMUSaveFormat compression)
-{
- virCommandPtr ret = NULL;
- const char *prog = qemuSaveCompressionTypeToString(compression);
-
- if (!prog) {
- virReportError(VIR_ERR_OPERATION_FAILED,
- _("Invalid compressed save format %d"),
- compression);
- return NULL;
- }
-
- ret = virCommandNew(prog);
- virCommandAddArg(ret, "-dc");
-
- if (compression == QEMU_SAVE_FORMAT_LZOP)
- virCommandAddArg(ret, "--ignore-warn");
-
- return ret;
-}
-
-
-/* Helper function to execute a migration to file with a correct save header
- * the caller needs to make sure that the processors are stopped and do all other
- * actions besides saving memory */
-static int
-qemuDomainSaveMemory(virQEMUDriverPtr driver,
- virDomainObjPtr vm,
- const char *path,
- virQEMUSaveDataPtr data,
- virCommandPtr compressor,
- unsigned int flags,
- qemuDomainAsyncJob asyncJob)
-{
- g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver);
- bool needUnlink = false;
- int ret = -1;
- int fd = -1;
- int directFlag = 0;
- virFileWrapperFdPtr wrapperFd = NULL;
- unsigned int wrapperFlags = VIR_FILE_WRAPPER_NON_BLOCKING;
-
- /* Obtain the file handle. */
- if ((flags & VIR_DOMAIN_SAVE_BYPASS_CACHE)) {
- wrapperFlags |= VIR_FILE_WRAPPER_BYPASS_CACHE;
- directFlag = virFileDirectFdFlag();
- if (directFlag < 0) {
- virReportError(VIR_ERR_OPERATION_FAILED, "%s",
- _("bypass cache unsupported by this system"));
- goto cleanup;
- }
- }
-
- fd = virQEMUFileOpenAs(cfg->user, cfg->group, false, path,
- O_WRONLY | O_TRUNC | O_CREAT | directFlag,
- &needUnlink);
- if (fd < 0)
- goto cleanup;
-
- if (qemuSecuritySetImageFDLabel(driver->securityManager, vm->def, fd) < 0)
- goto cleanup;
-
- if (!(wrapperFd = virFileWrapperFdNew(&fd, path, wrapperFlags)))
- goto cleanup;
-
- if (virQEMUSaveDataWrite(data, fd, path) < 0)
- goto cleanup;
-
- /* Perform the migration */
- if (qemuMigrationSrcToFile(driver, vm, fd, compressor, asyncJob) < 0)
- goto cleanup;
-
- /* Touch up file header to mark image complete. */
-
- /* Reopen the file to touch up the header, since we aren't set
- * up to seek backwards on wrapperFd. The reopened fd will
- * trigger a single page of file system cache pollution, but
- * that's acceptable. */
- if (VIR_CLOSE(fd) < 0) {
- virReportSystemError(errno, _("unable to close %s"), path);
- goto cleanup;
- }
-
- if (qemuDomainFileWrapperFDClose(vm, wrapperFd) < 0)
- goto cleanup;
-
- if ((fd = qemuDomainOpenFile(driver, vm, path, O_WRONLY, NULL)) < 0 ||
- virQEMUSaveDataFinish(data, &fd, path) < 0)
- goto cleanup;
-
- ret = 0;
-
- cleanup:
- VIR_FORCE_CLOSE(fd);
- if (qemuDomainFileWrapperFDClose(vm, wrapperFd) < 0)
- ret = -1;
- virFileWrapperFdFree(wrapperFd);
-
- if (ret < 0 && needUnlink)
- unlink(path);
-
- return ret;
-}
-
/* The vm must be active + locked. Vm will be unlocked and
* potentially free'd after this returns (eg transient VMs are freed
* shutdown). So 'vm' must not be referenced by the caller after
@@ -3192,8 +2870,8 @@ qemuDomainSaveInternal(virQEMUDriverPtr driver,
goto endjob;
xml = NULL;
- ret = qemuDomainSaveMemory(driver, vm, path, data, compressor,
- flags, QEMU_ASYNC_JOB_SAVE);
+ ret = qemuSaveImageCreate(driver, vm, path, data, compressor,
+ flags, QEMU_ASYNC_JOB_SAVE);
if (ret < 0)
goto endjob;
@@ -3231,87 +2909,6 @@ qemuDomainSaveInternal(virQEMUDriverPtr driver,
}
-/* qemuGetCompressionProgram:
- * @imageFormat: String representation from qemu.conf for the compression
- * image format being used (dump, save, or snapshot).
- * @compresspath: Pointer to a character string to store the fully qualified
- * path from virFindFileInPath.
- * @styleFormat: String representing the style of format (dump, save, snapshot)
- * @use_raw_on_fail: Boolean indicating how to handle the error path. For
- * callers that are OK with invalid data or inability to
- * find the compression program, just return a raw format
- * and let the path remain as NULL.
- *
- * Returns:
- * virQEMUSaveFormat - Integer representation of the compression
- * program to be used for particular style
- * (e.g. dump, save, or snapshot).
- * QEMU_SAVE_FORMAT_RAW - If there is no qemu.conf imageFormat value or
- * no there was an error, then just return RAW
- * indicating none.
- */
-static int ATTRIBUTE_NONNULL(2)
-qemuGetCompressionProgram(const char *imageFormat,
- virCommandPtr *compressor,
- const char *styleFormat,
- bool use_raw_on_fail)
-{
- int ret;
- const char *prog;
-
- *compressor = NULL;
-
- if (!imageFormat)
- return QEMU_SAVE_FORMAT_RAW;
-
- if ((ret = qemuSaveCompressionTypeFromString(imageFormat)) < 0)
- goto error;
-
- if (ret == QEMU_SAVE_FORMAT_RAW)
- return QEMU_SAVE_FORMAT_RAW;
-
- if (!(prog = virFindFileInPath(imageFormat)))
- goto error;
-
- *compressor = virCommandNew(prog);
- virCommandAddArg(*compressor, "-c");
- if (ret == QEMU_SAVE_FORMAT_XZ)
- virCommandAddArg(*compressor, "-3");
-
- return ret;
-
- error:
- if (ret < 0) {
- if (use_raw_on_fail)
- VIR_WARN("Invalid %s image format specified in "
- "configuration file, using raw",
- styleFormat);
- else
- virReportError(VIR_ERR_OPERATION_FAILED,
- _("Invalid %s image format specified "
- "in configuration file"),
- styleFormat);
- } else {
- if (use_raw_on_fail)
- VIR_WARN("Compression program for %s image format in "
- "configuration file isn't available, using raw",
- styleFormat);
- else
- virReportError(VIR_ERR_OPERATION_FAILED,
- _("Compression program for %s image format "
- "in configuration file isn't available"),
- styleFormat);
- }
-
- /* Use "raw" as the format if the specified format is not valid,
- * or the compress program is not available. */
- if (use_raw_on_fail)
- return QEMU_SAVE_FORMAT_RAW;
-
- return -1;
-}
-
-
static int
qemuDomainSaveFlags(virDomainPtr dom, const char *path, const char *dxml,
unsigned int flags)
@@ -3328,9 +2925,9 @@ qemuDomainSaveFlags(virDomainPtr dom, const char *path, const char *dxml,
VIR_DOMAIN_SAVE_PAUSED, -1);
cfg = virQEMUDriverGetConfig(driver);
- if ((compressed = qemuGetCompressionProgram(cfg->saveImageFormat,
- &compressor,
- "save", false)) < 0)
+ if ((compressed = qemuSaveImageGetCompressionProgram(cfg->saveImageFormat,
+ &compressor,
+ "save", false)) < 0)
goto cleanup;
if (!(vm = qemuDomainObjFromDomain(dom)))
@@ -3399,9 +2996,9 @@ qemuDomainManagedSave(virDomainPtr dom, unsigned int flags)
}
cfg = virQEMUDriverGetConfig(driver);
- if ((compressed = qemuGetCompressionProgram(cfg->saveImageFormat,
- &compressor,
- "save", false)) < 0)
+ if ((compressed = qemuSaveImageGetCompressionProgram(cfg->saveImageFormat,
+ &compressor,
+ "save", false)) < 0)
goto cleanup;
if (!(name = qemuDomainManagedSavePath(driver, vm)))
@@ -3613,9 +3210,9 @@ doCoreDump(virQEMUDriverPtr driver,
* format in "save" and "dump". This path doesn't need the compression
* program to exist and can ignore the return value - it only cares to
* get the compressor */
- ignore_value(qemuGetCompressionProgram(cfg->dumpImageFormat,
- &compressor,
- "dump", true));
+ ignore_value(qemuSaveImageGetCompressionProgram(cfg->dumpImageFormat,
+ &compressor,
+ "dump", true));
/* Create an empty file with appropriate ownership. */
if (dump_flags & VIR_DUMP_BYPASS_CACHE) {
@@ -6420,354 +6017,6 @@ static int qemuNodeGetSecurityModel(virConnectPtr conn,
}
-/**
- * qemuDomainSaveImageUpdateDef:
- * @driver: qemu driver data
- * @def: def of the domain from the save image
- * @newxml: user provided replacement XML
- *
- * Returns the new domain definition in case @newxml is ABI compatible with the
- * guest.
- */
-static virDomainDefPtr
-qemuDomainSaveImageUpdateDef(virQEMUDriverPtr driver,
- virDomainDefPtr def,
- const char *newxml)
-{
- virDomainDefPtr ret = NULL;
- virDomainDefPtr newdef_migr = NULL;
- virDomainDefPtr newdef = NULL;
-
- if (!(newdef = virDomainDefParseString(newxml, driver->xmlopt, NULL,
- VIR_DOMAIN_DEF_PARSE_INACTIVE)))
- goto cleanup;
-
- if (!(newdef_migr = qemuDomainDefCopy(driver, NULL,
- newdef,
- QEMU_DOMAIN_FORMAT_LIVE_FLAGS |
- VIR_DOMAIN_XML_MIGRATABLE)))
- goto cleanup;
-
- if (!virDomainDefCheckABIStability(def, newdef_migr, driver->xmlopt)) {
- virErrorPtr save_err;
-
- virErrorPreserveLast(&save_err);
-
- /* Due to a bug in older version of external snapshot creation
- * code, the XML saved in the save image was not a migratable
- * XML. To ensure backwards compatibility with the change of the
- * saved XML type, we need to check the ABI compatibility against
- * the user provided XML if the check against the migratable XML
- * fails. Snapshots created prior to v1.1.3 have this issue. */
- if (!virDomainDefCheckABIStability(def, newdef, driver->xmlopt)) {
- virErrorRestore(&save_err);
- goto cleanup;
- }
- virFreeError(save_err);
-
- /* use the user provided XML */
- ret = g_steal_pointer(&newdef);
- } else {
- ret = g_steal_pointer(&newdef_migr);
- }
-
- cleanup:
- virDomainDefFree(newdef);
- virDomainDefFree(newdef_migr);
-
- return ret;
-}
-
-
-/**
- * qemuDomainSaveImageOpen:
- * @driver: qemu driver data
- * @qemuCaps: pointer to qemuCaps if the domain is running or NULL
- * @path: path of the save image
- * @ret_def: returns domain definition created from the XML stored in the image
- * @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)
- * @unlink_corrupt: remove the image file if it is corrupted
- *
- * Returns the opened fd of the save image file and fills the appropriate fields
- * on success. On error returns -1 on most failures, -3 if corrupt image was
- * unlinked (no error raised).
- */
-static int ATTRIBUTE_NONNULL(3) ATTRIBUTE_NONNULL(4)
-qemuDomainSaveImageOpen(virQEMUDriverPtr driver,
- virQEMUCapsPtr qemuCaps,
- const char *path,
- virDomainDefPtr *ret_def,
- virQEMUSaveDataPtr *ret_data,
- bool bypass_cache,
- virFileWrapperFdPtr *wrapperFd,
- bool open_write,
- bool unlink_corrupt)
-{
- VIR_AUTOCLOSE fd = -1;
- int ret = -1;
- g_autoptr(virQEMUSaveData) data = NULL;
- virQEMUSaveHeaderPtr header;
- g_autoptr(virDomainDef) def = NULL;
- int oflags = open_write ? O_RDWR : O_RDONLY;
- size_t xml_len;
- size_t cookie_len;
-
- if (bypass_cache) {
- int directFlag = virFileDirectFdFlag();
- if (directFlag < 0) {
- virReportError(VIR_ERR_OPERATION_FAILED, "%s",
- _("bypass cache unsupported by this system"));
- return -1;
- }
- oflags |= directFlag;
- }
-
- if ((fd = qemuDomainOpenFile(driver, NULL, path, oflags, NULL)) < 0)
- return -1;
-
- if (bypass_cache &&
- !(*wrapperFd = virFileWrapperFdNew(&fd, path,
- VIR_FILE_WRAPPER_BYPASS_CACHE)))
- return -1;
-
- data = g_new0(virQEMUSaveData, 1);
-
- header = &data->header;
- if (saferead(fd, header, sizeof(*header)) != sizeof(*header)) {
- if (unlink_corrupt) {
- if (unlink(path) < 0) {
- virReportSystemError(errno,
- _("cannot remove corrupt file: %s"),
- path);
- return -1;
- } else {
- return -3;
- }
- }
-
- virReportError(VIR_ERR_OPERATION_FAILED,
- "%s", _("failed to read qemu header"));
- return -1;
- }
-
- if (memcmp(header->magic, QEMU_SAVE_MAGIC, sizeof(header->magic)) != 0) {
- if (memcmp(header->magic, QEMU_SAVE_PARTIAL, sizeof(header->magic)) == 0) {
- if (unlink_corrupt) {
- if (unlink(path) < 0) {
- virReportSystemError(errno,
- _("cannot remove corrupt file: %s"),
- path);
- return -1;
- } else {
- return -3;
- }
- }
-
- virReportError(VIR_ERR_OPERATION_FAILED, "%s",
- _("save image is incomplete"));
- return -1;
- }
-
- virReportError(VIR_ERR_OPERATION_FAILED, "%s",
- _("image magic is incorrect"));
- return -1;
- }
-
- if (header->version > QEMU_SAVE_VERSION) {
- /* convert endianness and try again */
- bswap_header(header);
- }
-
- if (header->version > QEMU_SAVE_VERSION) {
- virReportError(VIR_ERR_OPERATION_FAILED,
- _("image version is not supported (%d > %d)"),
- header->version, QEMU_SAVE_VERSION);
- return -1;
- }
-
- if (header->data_len <= 0) {
- virReportError(VIR_ERR_OPERATION_FAILED,
- _("invalid header data length: %d"), header->data_len);
- return -1;
- }
-
- if (header->cookieOffset)
- xml_len = header->cookieOffset;
- else
- xml_len = header->data_len;
-
- cookie_len = header->data_len - xml_len;
-
- data->xml = g_new0(char, xml_len);
-
- if (saferead(fd, data->xml, xml_len) != xml_len) {
- virReportError(VIR_ERR_OPERATION_FAILED,
- "%s", _("failed to read domain XML"));
- return -1;
- }
-
- if (cookie_len > 0) {
- data->cookie = g_new0(char, cookie_len);
-
- if (saferead(fd, data->cookie, cookie_len) != cookie_len) {
- virReportError(VIR_ERR_OPERATION_FAILED, "%s",
- _("failed to read cookie"));
- return -1;
- }
- }
-
- /* Create a domain from this XML */
- if (!(def = virDomainDefParseString(data->xml, driver->xmlopt, qemuCaps,
- VIR_DOMAIN_DEF_PARSE_INACTIVE |
- VIR_DOMAIN_DEF_PARSE_SKIP_VALIDATE)))
- return -1;
-
- *ret_def = g_steal_pointer(&def);
- *ret_data = g_steal_pointer(&data);
-
- ret = fd;
- fd = -1;
-
- return ret;
-}
-
-static int ATTRIBUTE_NONNULL(4) ATTRIBUTE_NONNULL(5) ATTRIBUTE_NONNULL(6)
-qemuDomainSaveImageStartVM(virConnectPtr conn,
- virQEMUDriverPtr driver,
- virDomainObjPtr vm,
- int *fd,
- virQEMUSaveDataPtr data,
- const char *path,
- bool start_paused,
- qemuDomainAsyncJob asyncJob)
-{
- qemuDomainObjPrivatePtr priv = vm->privateData;
- int ret = -1;
- bool started = false;
- virObjectEventPtr event;
- VIR_AUTOCLOSE intermediatefd = -1;
- g_autoptr(virCommand) cmd = NULL;
- g_autofree char *errbuf = NULL;
- g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver);
- virQEMUSaveHeaderPtr header = &data->header;
- g_autoptr(qemuDomainSaveCookie) cookie = NULL;
- int rc = 0;
-
- if (virSaveCookieParseString(data->cookie, (virObjectPtr *)&cookie,
- virDomainXMLOptionGetSaveCookie(driver->xmlopt)) < 0)
- goto cleanup;
-
- if ((header->version == 2) &&
- (header->compressed != QEMU_SAVE_FORMAT_RAW)) {
- if (!(cmd = qemuCompressGetCommand(header->compressed)))
- goto cleanup;
-
- intermediatefd = *fd;
- *fd = -1;
-
- virCommandSetInputFD(cmd, intermediatefd);
- virCommandSetOutputFD(cmd, fd);
- virCommandSetErrorBuffer(cmd, &errbuf);
- virCommandDoAsyncIO(cmd);
-
- if (virCommandRunAsync(cmd, NULL) < 0) {
- *fd = intermediatefd;
- intermediatefd = -1;
- goto cleanup;
- }
- }
-
- /* No cookie means libvirt which saved the domain was too old to mess up
- * the CPU definitions.
- */
- if (cookie &&
- qemuDomainFixupCPUs(vm, &cookie->cpu) < 0)
- goto cleanup;
-
- if (cookie && !cookie->slirpHelper)
- priv->disableSlirp = true;
-
- if (qemuProcessStart(conn, driver, vm, cookie ? cookie->cpu : NULL,
- asyncJob, "stdio", *fd, path, NULL,
- VIR_NETDEV_VPORT_PROFILE_OP_RESTORE,
- VIR_QEMU_PROCESS_START_PAUSED |
- VIR_QEMU_PROCESS_START_GEN_VMID) == 0)
- started = true;
-
- if (intermediatefd != -1) {
- virErrorPtr orig_err = NULL;
-
- if (!started) {
- /* if there was an error setting up qemu, the intermediate
- * process will wait forever to write to stdout, so we
- * must manually kill it and ignore any error related to
- * the process
- */
- virErrorPreserveLast(&orig_err);
- VIR_FORCE_CLOSE(intermediatefd);
- VIR_FORCE_CLOSE(*fd);
- }
-
- rc = virCommandWait(cmd, NULL);
- VIR_DEBUG("Decompression binary stderr: %s", NULLSTR(errbuf));
- virErrorRestore(&orig_err);
- }
- if (VIR_CLOSE(*fd) < 0) {
- virReportSystemError(errno, _("cannot close file: %s"), path);
- rc = -1;
- }
-
- virDomainAuditStart(vm, "restored", started);
- if (!started || rc < 0)
- goto cleanup;
-
- /* qemuProcessStart doesn't unset the qemu error reporting infrastructure
- * in case of migration (which is used in this case) so we need to reset it
- * so that the handle to virtlogd is not held open unnecessarily */
- qemuMonitorSetDomainLog(qemuDomainGetMonitor(vm), NULL, NULL, NULL);
-
- event = virDomainEventLifecycleNewFromObj(vm,
- VIR_DOMAIN_EVENT_STARTED,
- VIR_DOMAIN_EVENT_STARTED_RESTORED);
- virObjectEventStateQueue(driver->domainEventState, event);
-
-
- /* If it was running before, resume it now unless caller requested pause. */
- if (header->was_running && !start_paused) {
- if (qemuProcessStartCPUs(driver, vm,
- VIR_DOMAIN_RUNNING_RESTORED,
- asyncJob) < 0) {
- if (virGetLastErrorCode() == VIR_ERR_OK)
- virReportError(VIR_ERR_OPERATION_FAILED,
- "%s", _("failed to resume domain"));
- goto cleanup;
- }
- if (virDomainObjSave(vm, driver->xmlopt, cfg->stateDir) < 0) {
- VIR_WARN("Failed to save status on vm %s", vm->def->name);
- goto cleanup;
- }
- } else {
- int detail = (start_paused ? VIR_DOMAIN_EVENT_SUSPENDED_PAUSED :
- VIR_DOMAIN_EVENT_SUSPENDED_RESTORED);
- event = virDomainEventLifecycleNewFromObj(vm,
- VIR_DOMAIN_EVENT_SUSPENDED,
- detail);
- virObjectEventStateQueue(driver->domainEventState, event);
- }
-
- ret = 0;
-
- cleanup:
- if (ret < 0 && started) {
- qemuProcessStop(driver, vm, VIR_DOMAIN_SHUTOFF_FAILED,
- asyncJob, VIR_QEMU_PROCESS_STOP_MIGRATED);
- }
- return ret;
-}
-
static int
qemuDomainRestoreFlags(virConnectPtr conn,
const char *path,
@@ -6793,9 +6042,9 @@ qemuDomainRestoreFlags(virConnectPtr conn,
virNWFilterReadLockFilterUpdates();
- fd = qemuDomainSaveImageOpen(driver, NULL, path, &def, &data,
- (flags & VIR_DOMAIN_SAVE_BYPASS_CACHE) != 0,
- &wrapperFd, false, false);
+ fd = qemuSaveImageOpen(driver, NULL, path, &def, &data,
+ (flags & VIR_DOMAIN_SAVE_BYPASS_CACHE) != 0,
+ &wrapperFd, false, false);
if (fd < 0)
goto cleanup;
@@ -6822,7 +6071,7 @@ qemuDomainRestoreFlags(virConnectPtr conn,
if (newxml) {
virDomainDefPtr tmp;
- if (!(tmp = qemuDomainSaveImageUpdateDef(driver, def, newxml)))
+ if (!(tmp = qemuSaveImageUpdateDef(driver, def, newxml)))
goto cleanup;
virDomainDefFree(def);
@@ -6851,8 +6100,8 @@ qemuDomainRestoreFlags(virConnectPtr conn,
flags) < 0)
goto cleanup;
- ret = qemuDomainSaveImageStartVM(conn, driver, vm, &fd, data, path,
- false, QEMU_ASYNC_JOB_START);
+ ret = qemuSaveImageStartVM(conn, driver, vm, &fd, data, path,
+ false, QEMU_ASYNC_JOB_START);
qemuProcessEndJob(driver, vm);
@@ -6889,8 +6138,8 @@ qemuDomainSaveImageGetXMLDesc(virConnectPtr conn, const char *path,
virCheckFlags(VIR_DOMAIN_SAVE_IMAGE_XML_SECURE, NULL);
- fd = qemuDomainSaveImageOpen(driver, NULL, path, &def, &data,
- false, NULL, false, false);
+ fd = qemuSaveImageOpen(driver, NULL, path, &def, &data,
+ false, NULL, false, false);
if (fd < 0)
goto cleanup;
@@ -6927,8 +6176,8 @@ qemuDomainSaveImageDefineXML(virConnectPtr conn, const char *path,
else if (flags & VIR_DOMAIN_SAVE_PAUSED)
state = 0;
- fd = qemuDomainSaveImageOpen(driver, NULL, path, &def, &data,
- false, NULL, true, false);
+ fd = qemuSaveImageOpen(driver, NULL, path, &def, &data,
+ false, NULL, true, false);
if (fd < 0)
goto cleanup;
@@ -6946,7 +6195,7 @@ qemuDomainSaveImageDefineXML(virConnectPtr conn, const char *path,
if (state >= 0)
data->header.was_running = state;
- if (!(newdef = qemuDomainSaveImageUpdateDef(driver, def, dxml)))
+ if (!(newdef = qemuSaveImageUpdateDef(driver, def, dxml)))
goto cleanup;
VIR_FREE(data->xml);
@@ -7011,8 +6260,8 @@ qemuDomainManagedSaveGetXMLDesc(virDomainPtr dom, unsigned int flags)
goto cleanup;
}
- if ((fd = qemuDomainSaveImageOpen(driver, priv->qemuCaps, path, &def, &data,
- false, NULL, false, false)) < 0)
+ if ((fd = qemuSaveImageOpen(driver, priv->qemuCaps, path, &def, &data,
+ false, NULL, false, false)) < 0)
goto cleanup;
ret = qemuDomainDefFormatXML(driver, priv->qemuCaps, def, flags);
@@ -7076,8 +6325,8 @@ qemuDomainObjRestore(virConnectPtr conn,
virQEMUSaveDataPtr data = NULL;
virFileWrapperFdPtr wrapperFd = NULL;
- fd = qemuDomainSaveImageOpen(driver, NULL, path, &def, &data,
- bypass_cache, &wrapperFd, false, true);
+ fd = qemuSaveImageOpen(driver, NULL, path, &def, &data,
+ bypass_cache, &wrapperFd, false, true);
if (fd < 0) {
if (fd == -3)
ret = 1;
@@ -7098,7 +6347,7 @@ qemuDomainObjRestore(virConnectPtr conn,
VIR_DEBUG("Using hook-filtered domain XML: %s", xmlout);
- if (!(tmp = qemuDomainSaveImageUpdateDef(driver, def, xmlout)))
+ if (!(tmp = qemuSaveImageUpdateDef(driver, def, xmlout)))
goto cleanup;
virDomainDefFree(def);
@@ -7124,8 +6373,8 @@ qemuDomainObjRestore(virConnectPtr conn,
virDomainObjAssignDef(vm, def, true, NULL);
def = NULL;
- ret = qemuDomainSaveImageStartVM(conn, driver, vm, &fd, data, path,
- start_paused, asyncJob);
+ ret = qemuSaveImageStartVM(conn, driver, vm, &fd, data, path,
+ start_paused, asyncJob);
cleanup:
virQEMUSaveDataFree(data);
@@ -15333,9 +14582,9 @@ qemuDomainSnapshotCreateActiveExternal(virQEMUDriverPtr driver,
JOB_MASK(QEMU_JOB_SUSPEND) |
JOB_MASK(QEMU_JOB_MIGRATION_OP)));
- if ((compressed = qemuGetCompressionProgram(cfg->snapshotImageFormat,
- &compressor,
- "snapshot", false)) < 0)
+ if ((compressed = qemuSaveImageGetCompressionProgram(cfg->snapshotImageFormat,
+ &compressor,
+ "snapshot", false)) < 0)
goto cleanup;
if (!(xml = qemuDomainDefFormatLive(driver, priv->qemuCaps,
@@ -15350,9 +14599,9 @@ qemuDomainSnapshotCreateActiveExternal(virQEMUDriverPtr driver,
goto cleanup;
xml = NULL;
- if ((ret = qemuDomainSaveMemory(driver, vm, snapdef->file, data,
- compressor, 0,
- QEMU_ASYNC_JOB_SNAPSHOT)) < 0)
+ if ((ret = qemuSaveImageCreate(driver, vm, snapdef->file, data,
+ compressor, 0,
+ QEMU_ASYNC_JOB_SNAPSHOT)) < 0)
goto cleanup;
/* the memory image was created, remove it on errors */
diff --git a/src/qemu/qemu_saveimage.c b/src/qemu/qemu_saveimage.c
new file mode 100644
index 0000000000..52468056ad
--- /dev/null
+++ b/src/qemu/qemu_saveimage.c
@@ -0,0 +1,764 @@
+/*
+ * qemu_saveimage.c: Infrastructure for saving qemu state to a file
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+
+#include "qemu_saveimage.h"
+#include "qemu_domain.h"
+#include "qemu_migration.h"
+#include "qemu_process.h"
+#include "qemu_security.h"
+
+#include "domain_audit.h"
+
+#include "virerror.h"
+#include "virlog.h"
+#include "viralloc.h"
+#include "virqemu.h"
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#define VIR_FROM_THIS VIR_FROM_QEMU
+
+VIR_LOG_INIT("qemu.qemu_saveimage");
+
+typedef enum {
+ QEMU_SAVE_FORMAT_RAW = 0,
+ QEMU_SAVE_FORMAT_GZIP = 1,
+ QEMU_SAVE_FORMAT_BZIP2 = 2,
+ /*
+ * Deprecated by xz and never used as part of a release
+ * QEMU_SAVE_FORMAT_LZMA
+ */
+ QEMU_SAVE_FORMAT_XZ = 3,
+ QEMU_SAVE_FORMAT_LZOP = 4,
+ /* Note: add new members only at the end.
+ These values are used in the on-disk format.
+ Do not change or re-use numbers. */
+
+ QEMU_SAVE_FORMAT_LAST
+} virQEMUSaveFormat;
+
+VIR_ENUM_DECL(qemuSaveCompression);
+VIR_ENUM_IMPL(qemuSaveCompression,
+ QEMU_SAVE_FORMAT_LAST,
+ "raw",
+ "gzip",
+ "bzip2",
+ "xz",
+ "lzop",
+);
+
+static inline void
+qemuSaveImageBswapHeader(virQEMUSaveHeaderPtr hdr)
+{
+ hdr->version = GUINT32_SWAP_LE_BE(hdr->version);
+ hdr->data_len = GUINT32_SWAP_LE_BE(hdr->data_len);
+ hdr->was_running = GUINT32_SWAP_LE_BE(hdr->was_running);
+ hdr->compressed = GUINT32_SWAP_LE_BE(hdr->compressed);
+ hdr->cookieOffset = GUINT32_SWAP_LE_BE(hdr->cookieOffset);
+}
+
+
+void
+virQEMUSaveDataFree(virQEMUSaveDataPtr data)
+{
+ if (!data)
+ return;
+
+ VIR_FREE(data->xml);
+ VIR_FREE(data->cookie);
+ VIR_FREE(data);
+}
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC(virQEMUSaveData, virQEMUSaveDataFree);
+
+/**
+ * This function steals @domXML on success.
+ */
+virQEMUSaveDataPtr
+virQEMUSaveDataNew(char *domXML,
+ qemuDomainSaveCookiePtr cookieObj,
+ bool running,
+ int compressed,
+ virDomainXMLOptionPtr xmlopt)
+{
+ virQEMUSaveDataPtr data = NULL;
+ virQEMUSaveHeaderPtr header;
+
+ if (VIR_ALLOC(data) < 0)
+ return NULL;
+
+ data->xml = g_steal_pointer(&domXML);
+
+ if (cookieObj &&
+ !(data->cookie = virSaveCookieFormat((virObjectPtr) cookieObj,
+ virDomainXMLOptionGetSaveCookie(xmlopt))))
+ goto error;
+
+ 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 data;
+
+ error:
+ virQEMUSaveDataFree(data);
+ return NULL;
+}
+
+
+/* virQEMUSaveDataWrite:
+ *
+ * Writes libvirt's header (including domain XML) into a saved image of a
+ * running domain. If @header has data_len filled in (because it was previously
+ * read from the file), the function will make sure the new data will fit
+ * within data_len.
+ *
+ * Returns -1 on failure, or 0 on success.
+ */
+int
+virQEMUSaveDataWrite(virQEMUSaveDataPtr data,
+ int fd,
+ const char *path)
+{
+ virQEMUSaveHeaderPtr header = &data->header;
+ size_t len;
+ size_t xml_len;
+ size_t cookie_len = 0;
+ size_t zerosLen = 0;
+ g_autofree char *zeros = NULL;
+
+ xml_len = strlen(data->xml) + 1;
+ if (data->cookie)
+ cookie_len = strlen(data->cookie) + 1;
+
+ len = xml_len + cookie_len;
+
+ if (header->data_len == 0) {
+ /* This 64kb padding allows the user to edit the XML in
+ * a saved state image and have the new XML be larger
+ * that what was originally saved
+ */
+ header->data_len = len + (64 * 1024);
+ } else {
+ if (len > header->data_len) {
+ virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+ _("new xml too large to fit in file"));
+ return -1;
+ }
+ }
+
+ zerosLen = header->data_len - len;
+ zeros = g_new0(char, zerosLen);
+
+ if (data->cookie)
+ header->cookieOffset = xml_len;
+
+ if (safewrite(fd, header, sizeof(*header)) != sizeof(*header)) {
+ virReportSystemError(errno,
+ _("failed to write header to domain save file '%s'"),
+ path);
+ return -1;
+ }
+
+ if (safewrite(fd, data->xml, xml_len) != xml_len) {
+ virReportSystemError(errno,
+ _("failed to write domain xml to '%s'"),
+ path);
+ return -1;
+ }
+
+ if (data->cookie &&
+ safewrite(fd, data->cookie, cookie_len) != cookie_len) {
+ virReportSystemError(errno,
+ _("failed to write cookie to '%s'"),
+ path);
+ return -1;
+ }
+
+ if (safewrite(fd, zeros, zerosLen) != zerosLen) {
+ virReportSystemError(errno,
+ _("failed to write padding to '%s'"),
+ path);
+ return -1;
+ }
+
+ return 0;
+}
+
+
+static int
+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) ||
+ VIR_CLOSE(*fd) < 0) {
+ virReportSystemError(errno,
+ _("failed to write header to domain save file '%s'"),
+ path);
+ return -1;
+ }
+
+ return 0;
+}
+
+
+static virCommandPtr
+qemuSaveImageGetCompressionCommand(virQEMUSaveFormat compression)
+{
+ virCommandPtr ret = NULL;
+ const char *prog = qemuSaveCompressionTypeToString(compression);
+
+ if (!prog) {
+ virReportError(VIR_ERR_OPERATION_FAILED,
+ _("Invalid compressed save format %d"),
+ compression);
+ return NULL;
+ }
+
+ ret = virCommandNew(prog);
+ virCommandAddArg(ret, "-dc");
+
+ if (compression == QEMU_SAVE_FORMAT_LZOP)
+ virCommandAddArg(ret, "--ignore-warn");
+
+ return ret;
+}
+
+
+/* Helper function to execute a migration to file with a correct save header
+ * the caller needs to make sure that the processors are stopped and do all other
+ * actions besides saving memory */
+int
+qemuSaveImageCreate(virQEMUDriverPtr driver,
+ virDomainObjPtr vm,
+ const char *path,
+ virQEMUSaveDataPtr data,
+ virCommandPtr compressor,
+ unsigned int flags,
+ qemuDomainAsyncJob asyncJob)
+{
+ g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver);
+ bool needUnlink = false;
+ int ret = -1;
+ int fd = -1;
+ int directFlag = 0;
+ virFileWrapperFdPtr wrapperFd = NULL;
+ unsigned int wrapperFlags = VIR_FILE_WRAPPER_NON_BLOCKING;
+
+ /* Obtain the file handle. */
+ if ((flags & VIR_DOMAIN_SAVE_BYPASS_CACHE)) {
+ wrapperFlags |= VIR_FILE_WRAPPER_BYPASS_CACHE;
+ directFlag = virFileDirectFdFlag();
+ if (directFlag < 0) {
+ virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+ _("bypass cache unsupported by this system"));
+ goto cleanup;
+ }
+ }
+
+ fd = virQEMUFileOpenAs(cfg->user, cfg->group, false, path,
+ O_WRONLY | O_TRUNC | O_CREAT | directFlag,
+ &needUnlink);
+ if (fd < 0)
+ goto cleanup;
+
+ if (qemuSecuritySetImageFDLabel(driver->securityManager, vm->def, fd) < 0)
+ goto cleanup;
+
+ if (!(wrapperFd = virFileWrapperFdNew(&fd, path, wrapperFlags)))
+ goto cleanup;
+
+ if (virQEMUSaveDataWrite(data, fd, path) < 0)
+ goto cleanup;
+
+ /* Perform the migration */
+ if (qemuMigrationSrcToFile(driver, vm, fd, compressor, asyncJob) < 0)
+ goto cleanup;
+
+ /* Touch up file header to mark image complete. */
+
+ /* Reopen the file to touch up the header, since we aren't set
+ * up to seek backwards on wrapperFd. The reopened fd will
+ * trigger a single page of file system cache pollution, but
+ * that's acceptable. */
+ if (VIR_CLOSE(fd) < 0) {
+ virReportSystemError(errno, _("unable to close %s"), path);
+ goto cleanup;
+ }
+
+ if (qemuDomainFileWrapperFDClose(vm, wrapperFd) < 0)
+ goto cleanup;
+
+ if ((fd = qemuDomainOpenFile(driver, vm, path, O_WRONLY, NULL)) < 0 ||
+ virQEMUSaveDataFinish(data, &fd, path) < 0)
+ goto cleanup;
+
+ ret = 0;
+
+ cleanup:
+ VIR_FORCE_CLOSE(fd);
+ if (qemuDomainFileWrapperFDClose(vm, wrapperFd) < 0)
+ ret = -1;
+ virFileWrapperFdFree(wrapperFd);
+
+ if (ret < 0 && needUnlink)
+ unlink(path);
+
+ return ret;
+}
+
+
+/* qemuSaveImageGetCompressionProgram:
+ * @imageFormat: String representation from qemu.conf for the compression
+ * image format being used (dump, save, or snapshot).
+ * @compresspath: Pointer to a character string to store the fully qualified
+ * path from virFindFileInPath.
+ * @styleFormat: String representing the style of format (dump, save, snapshot)
+ * @use_raw_on_fail: Boolean indicating how to handle the error path. For
+ * callers that are OK with invalid data or inability to
+ * find the compression program, just return a raw format
+ * and let the path remain as NULL.
+ *
+ * Returns:
+ * virQEMUSaveFormat - Integer representation of the compression
+ * program to be used for particular style
+ * (e.g. dump, save, or snapshot).
+ * QEMU_SAVE_FORMAT_RAW - If there is no qemu.conf imageFormat value or
+ * no there was an error, then just return RAW
+ * indicating none.
+ */
+int
+qemuSaveImageGetCompressionProgram(const char *imageFormat,
+ virCommandPtr *compressor,
+ const char *styleFormat,
+ bool use_raw_on_fail)
+{
+ int ret;
+ const char *prog;
+
+ *compressor = NULL;
+
+ if (!imageFormat)
+ return QEMU_SAVE_FORMAT_RAW;
+
+ if ((ret = qemuSaveCompressionTypeFromString(imageFormat)) < 0)
+ goto error;
+
+ if (ret == QEMU_SAVE_FORMAT_RAW)
+ return QEMU_SAVE_FORMAT_RAW;
+
+ if (!(prog = virFindFileInPath(imageFormat)))
+ goto error;
+
+ *compressor = virCommandNew(prog);
+ virCommandAddArg(*compressor, "-c");
+ if (ret == QEMU_SAVE_FORMAT_XZ)
+ virCommandAddArg(*compressor, "-3");
+
+ return ret;
+
+ error:
+ if (ret < 0) {
+ if (use_raw_on_fail)
+ VIR_WARN("Invalid %s image format specified in "
+ "configuration file, using raw",
+ styleFormat);
+ else
+ virReportError(VIR_ERR_OPERATION_FAILED,
+ _("Invalid %s image format specified "
+ "in configuration file"),
+ styleFormat);
+ } else {
+ if (use_raw_on_fail)
+ VIR_WARN("Compression program for %s image format in "
+ "configuration file isn't available, using raw",
+ styleFormat);
+ else
+ virReportError(VIR_ERR_OPERATION_FAILED,
+ _("Compression program for %s image format "
+ "in configuration file isn't available"),
+ styleFormat);
+ }
+
+ /* Use "raw" as the format if the specified format is not valid,
+ * or the compress program is not available. */
+ if (use_raw_on_fail)
+ return QEMU_SAVE_FORMAT_RAW;
+
+ return -1;
+}
+
+
+/**
+ * qemuSaveImageOpen:
+ * @driver: qemu driver data
+ * @qemuCaps: pointer to qemuCaps if the domain is running or NULL
+ * @path: path of the save image
+ * @ret_def: returns domain definition created from the XML stored in the image
+ * @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)
+ * @unlink_corrupt: remove the image file if it is corrupted
+ *
+ * Returns the opened fd of the save image file and fills the appropriate fields
+ * on success. On error returns -1 on most failures, -3 if corrupt image was
+ * unlinked (no error raised).
+ */
+int
+qemuSaveImageOpen(virQEMUDriverPtr driver,
+ virQEMUCapsPtr qemuCaps,
+ const char *path,
+ virDomainDefPtr *ret_def,
+ virQEMUSaveDataPtr *ret_data,
+ bool bypass_cache,
+ virFileWrapperFdPtr *wrapperFd,
+ bool open_write,
+ bool unlink_corrupt)
+{
+ VIR_AUTOCLOSE fd = -1;
+ int ret = -1;
+ g_autoptr(virQEMUSaveData) data = NULL;
+ virQEMUSaveHeaderPtr header;
+ g_autoptr(virDomainDef) def = NULL;
+ int oflags = open_write ? O_RDWR : O_RDONLY;
+ size_t xml_len;
+ size_t cookie_len;
+
+ if (bypass_cache) {
+ int directFlag = virFileDirectFdFlag();
+ if (directFlag < 0) {
+ virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+ _("bypass cache unsupported by this system"));
+ return -1;
+ }
+ oflags |= directFlag;
+ }
+
+ if ((fd = qemuDomainOpenFile(driver, NULL, path, oflags, NULL)) < 0)
+ return -1;
+
+ if (bypass_cache &&
+ !(*wrapperFd = virFileWrapperFdNew(&fd, path,
+ VIR_FILE_WRAPPER_BYPASS_CACHE)))
+ return -1;
+
+ data = g_new0(virQEMUSaveData, 1);
+
+ header = &data->header;
+ if (saferead(fd, header, sizeof(*header)) != sizeof(*header)) {
+ if (unlink_corrupt) {
+ if (unlink(path) < 0) {
+ virReportSystemError(errno,
+ _("cannot remove corrupt file: %s"),
+ path);
+ return -1;
+ } else {
+ return -3;
+ }
+ }
+
+ virReportError(VIR_ERR_OPERATION_FAILED,
+ "%s", _("failed to read qemu header"));
+ return -1;
+ }
+
+ if (memcmp(header->magic, QEMU_SAVE_MAGIC, sizeof(header->magic)) != 0) {
+ if (memcmp(header->magic, QEMU_SAVE_PARTIAL, sizeof(header->magic)) == 0) {
+ if (unlink_corrupt) {
+ if (unlink(path) < 0) {
+ virReportSystemError(errno,
+ _("cannot remove corrupt file: %s"),
+ path);
+ return -1;
+ } else {
+ return -3;
+ }
+ }
+
+ virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+ _("save image is incomplete"));
+ return -1;
+ }
+
+ virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+ _("image magic is incorrect"));
+ return -1;
+ }
+
+ if (header->version > QEMU_SAVE_VERSION) {
+ /* convert endianness and try again */
+ qemuSaveImageBswapHeader(header);
+ }
+
+ if (header->version > QEMU_SAVE_VERSION) {
+ virReportError(VIR_ERR_OPERATION_FAILED,
+ _("image version is not supported (%d > %d)"),
+ header->version, QEMU_SAVE_VERSION);
+ return -1;
+ }
+
+ if (header->data_len <= 0) {
+ virReportError(VIR_ERR_OPERATION_FAILED,
+ _("invalid header data length: %d"), header->data_len);
+ return -1;
+ }
+
+ if (header->cookieOffset)
+ xml_len = header->cookieOffset;
+ else
+ xml_len = header->data_len;
+
+ cookie_len = header->data_len - xml_len;
+
+ data->xml = g_new0(char, xml_len);
+
+ if (saferead(fd, data->xml, xml_len) != xml_len) {
+ virReportError(VIR_ERR_OPERATION_FAILED,
+ "%s", _("failed to read domain XML"));
+ return -1;
+ }
+
+ if (cookie_len > 0) {
+ data->cookie = g_new0(char, cookie_len);
+
+ if (saferead(fd, data->cookie, cookie_len) != cookie_len) {
+ virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+ _("failed to read cookie"));
+ return -1;
+ }
+ }
+
+ /* Create a domain from this XML */
+ if (!(def = virDomainDefParseString(data->xml, driver->xmlopt, qemuCaps,
+ VIR_DOMAIN_DEF_PARSE_INACTIVE |
+ VIR_DOMAIN_DEF_PARSE_SKIP_VALIDATE)))
+ return -1;
+
+ *ret_def = g_steal_pointer(&def);
+ *ret_data = g_steal_pointer(&data);
+
+ ret = fd;
+ fd = -1;
+
+ return ret;
+}
+
+int
+qemuSaveImageStartVM(virConnectPtr conn,
+ virQEMUDriverPtr driver,
+ virDomainObjPtr vm,
+ int *fd,
+ virQEMUSaveDataPtr data,
+ const char *path,
+ bool start_paused,
+ qemuDomainAsyncJob asyncJob)
+{
+ qemuDomainObjPrivatePtr priv = vm->privateData;
+ int ret = -1;
+ bool started = false;
+ virObjectEventPtr event;
+ VIR_AUTOCLOSE intermediatefd = -1;
+ g_autoptr(virCommand) cmd = NULL;
+ g_autofree char *errbuf = NULL;
+ g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver);
+ virQEMUSaveHeaderPtr header = &data->header;
+ g_autoptr(qemuDomainSaveCookie) cookie = NULL;
+ int rc = 0;
+
+ if (virSaveCookieParseString(data->cookie, (virObjectPtr *)&cookie,
+ virDomainXMLOptionGetSaveCookie(driver->xmlopt)) < 0)
+ goto cleanup;
+
+ if ((header->version == 2) &&
+ (header->compressed != QEMU_SAVE_FORMAT_RAW)) {
+ if (!(cmd = qemuSaveImageGetCompressionCommand(header->compressed)))
+ goto cleanup;
+
+ intermediatefd = *fd;
+ *fd = -1;
+
+ virCommandSetInputFD(cmd, intermediatefd);
+ virCommandSetOutputFD(cmd, fd);
+ virCommandSetErrorBuffer(cmd, &errbuf);
+ virCommandDoAsyncIO(cmd);
+
+ if (virCommandRunAsync(cmd, NULL) < 0) {
+ *fd = intermediatefd;
+ intermediatefd = -1;
+ goto cleanup;
+ }
+ }
+
+ /* No cookie means libvirt which saved the domain was too old to mess up
+ * the CPU definitions.
+ */
+ if (cookie &&
+ qemuDomainFixupCPUs(vm, &cookie->cpu) < 0)
+ goto cleanup;
+
+ if (cookie && !cookie->slirpHelper)
+ priv->disableSlirp = true;
+
+ if (qemuProcessStart(conn, driver, vm, cookie ? cookie->cpu : NULL,
+ asyncJob, "stdio", *fd, path, NULL,
+ VIR_NETDEV_VPORT_PROFILE_OP_RESTORE,
+ VIR_QEMU_PROCESS_START_PAUSED |
+ VIR_QEMU_PROCESS_START_GEN_VMID) == 0)
+ started = true;
+
+ if (intermediatefd != -1) {
+ virErrorPtr orig_err = NULL;
+
+ if (!started) {
+ /* if there was an error setting up qemu, the intermediate
+ * process will wait forever to write to stdout, so we
+ * must manually kill it and ignore any error related to
+ * the process
+ */
+ virErrorPreserveLast(&orig_err);
+ VIR_FORCE_CLOSE(intermediatefd);
+ VIR_FORCE_CLOSE(*fd);
+ }
+
+ rc = virCommandWait(cmd, NULL);
+ VIR_DEBUG("Decompression binary stderr: %s", NULLSTR(errbuf));
+ virErrorRestore(&orig_err);
+ }
+ if (VIR_CLOSE(*fd) < 0) {
+ virReportSystemError(errno, _("cannot close file: %s"), path);
+ rc = -1;
+ }
+
+ virDomainAuditStart(vm, "restored", started);
+ if (!started || rc < 0)
+ goto cleanup;
+
+ /* qemuProcessStart doesn't unset the qemu error reporting infrastructure
+ * in case of migration (which is used in this case) so we need to reset it
+ * so that the handle to virtlogd is not held open unnecessarily */
+ qemuMonitorSetDomainLog(qemuDomainGetMonitor(vm), NULL, NULL, NULL);
+
+ event = virDomainEventLifecycleNewFromObj(vm,
+ VIR_DOMAIN_EVENT_STARTED,
+ VIR_DOMAIN_EVENT_STARTED_RESTORED);
+ virObjectEventStateQueue(driver->domainEventState, event);
+
+
+ /* If it was running before, resume it now unless caller requested pause. */
+ if (header->was_running && !start_paused) {
+ if (qemuProcessStartCPUs(driver, vm,
+ VIR_DOMAIN_RUNNING_RESTORED,
+ asyncJob) < 0) {
+ if (virGetLastErrorCode() == VIR_ERR_OK)
+ virReportError(VIR_ERR_OPERATION_FAILED,
+ "%s", _("failed to resume domain"));
+ goto cleanup;
+ }
+ if (virDomainObjSave(vm, driver->xmlopt, cfg->stateDir) < 0) {
+ VIR_WARN("Failed to save status on vm %s", vm->def->name);
+ goto cleanup;
+ }
+ } else {
+ int detail = (start_paused ? VIR_DOMAIN_EVENT_SUSPENDED_PAUSED :
+ VIR_DOMAIN_EVENT_SUSPENDED_RESTORED);
+ event = virDomainEventLifecycleNewFromObj(vm,
+ VIR_DOMAIN_EVENT_SUSPENDED,
+ detail);
+ virObjectEventStateQueue(driver->domainEventState, event);
+ }
+
+ ret = 0;
+
+ cleanup:
+ if (ret < 0 && started) {
+ qemuProcessStop(driver, vm, VIR_DOMAIN_SHUTOFF_FAILED,
+ asyncJob, VIR_QEMU_PROCESS_STOP_MIGRATED);
+ }
+ return ret;
+}
+
+
+/**
+ * qemuSaveImageUpdateDef:
+ * @driver: qemu driver data
+ * @def: def of the domain from the save image
+ * @newxml: user provided replacement XML
+ *
+ * Returns the new domain definition in case @newxml is ABI compatible with the
+ * guest.
+ */
+virDomainDefPtr
+qemuSaveImageUpdateDef(virQEMUDriverPtr driver,
+ virDomainDefPtr def,
+ const char *newxml)
+{
+ virDomainDefPtr ret = NULL;
+ virDomainDefPtr newdef_migr = NULL;
+ virDomainDefPtr newdef = NULL;
+
+ if (!(newdef = virDomainDefParseString(newxml, driver->xmlopt, NULL,
+ VIR_DOMAIN_DEF_PARSE_INACTIVE)))
+ goto cleanup;
+
+ if (!(newdef_migr = qemuDomainDefCopy(driver, NULL,
+ newdef,
+ QEMU_DOMAIN_FORMAT_LIVE_FLAGS |
+ VIR_DOMAIN_XML_MIGRATABLE)))
+ goto cleanup;
+
+ if (!virDomainDefCheckABIStability(def, newdef_migr, driver->xmlopt)) {
+ virErrorPtr save_err;
+
+ virErrorPreserveLast(&save_err);
+
+ /* Due to a bug in older version of external snapshot creation
+ * code, the XML saved in the save image was not a migratable
+ * XML. To ensure backwards compatibility with the change of the
+ * saved XML type, we need to check the ABI compatibility against
+ * the user provided XML if the check against the migratable XML
+ * fails. Snapshots created prior to v1.1.3 have this issue. */
+ if (!virDomainDefCheckABIStability(def, newdef, driver->xmlopt)) {
+ virErrorRestore(&save_err);
+ goto cleanup;
+ }
+ virFreeError(save_err);
+
+ /* use the user provided XML */
+ ret = g_steal_pointer(&newdef);
+ } else {
+ ret = g_steal_pointer(&newdef_migr);
+ }
+
+ cleanup:
+ virDomainDefFree(newdef);
+ virDomainDefFree(newdef_migr);
+
+ return ret;
+}
diff --git a/src/qemu/qemu_saveimage.h b/src/qemu/qemu_saveimage.h
new file mode 100644
index 0000000000..f9fecbcc46
--- /dev/null
+++ b/src/qemu/qemu_saveimage.h
@@ -0,0 +1,116 @@
+/*
+ * qemu_saveimage.h: Infrastructure for saving qemu state to a file
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include "virconftypes.h"
+#include "datatypes.h"
+
+#include "qemu_conf.h"
+#include "qemu_domainjob.h"
+#include "qemu_domain.h"
+
+/* It would be nice to replace 'Qemud' with 'Qemu' but
+ * this magic string is ABI, so it can't be changed
+ */
+#define QEMU_SAVE_MAGIC "LibvirtQemudSave"
+#define QEMU_SAVE_PARTIAL "LibvirtQemudPart"
+#define QEMU_SAVE_VERSION 2
+
+G_STATIC_ASSERT(sizeof(QEMU_SAVE_MAGIC) == sizeof(QEMU_SAVE_PARTIAL));
+
+typedef struct _virQEMUSaveHeader virQEMUSaveHeader;
+typedef virQEMUSaveHeader *virQEMUSaveHeaderPtr;
+struct _virQEMUSaveHeader {
+ char magic[sizeof(QEMU_SAVE_MAGIC)-1];
+ uint32_t version;
+ uint32_t data_len;
+ uint32_t was_running;
+ uint32_t compressed;
+ uint32_t cookieOffset;
+ uint32_t unused[14];
+};
+
+
+typedef struct _virQEMUSaveData virQEMUSaveData;
+typedef virQEMUSaveData *virQEMUSaveDataPtr;
+struct _virQEMUSaveData {
+ virQEMUSaveHeader header;
+ char *xml;
+ char *cookie;
+};
+
+
+virDomainDefPtr
+qemuSaveImageUpdateDef(virQEMUDriverPtr driver,
+ virDomainDefPtr def,
+ const char *newxml);
+
+int
+qemuSaveImageStartVM(virConnectPtr conn,
+ virQEMUDriverPtr driver,
+ virDomainObjPtr vm,
+ int *fd,
+ virQEMUSaveDataPtr data,
+ const char *path,
+ bool start_paused,
+ qemuDomainAsyncJob asyncJob)
+ ATTRIBUTE_NONNULL(4) ATTRIBUTE_NONNULL(5) ATTRIBUTE_NONNULL(6);
+
+int
+qemuSaveImageOpen(virQEMUDriverPtr driver,
+ virQEMUCapsPtr qemuCaps,
+ const char *path,
+ virDomainDefPtr *ret_def,
+ virQEMUSaveDataPtr *ret_data,
+ bool bypass_cache,
+ virFileWrapperFdPtr *wrapperFd,
+ bool open_write,
+ bool unlink_corrupt)
+ ATTRIBUTE_NONNULL(3) ATTRIBUTE_NONNULL(4);
+
+int
+qemuSaveImageGetCompressionProgram(const char *imageFormat,
+ virCommandPtr *compressor,
+ const char *styleFormat,
+ bool use_raw_on_fail)
+ ATTRIBUTE_NONNULL(2);
+
+int
+qemuSaveImageCreate(virQEMUDriverPtr driver,
+ virDomainObjPtr vm,
+ const char *path,
+ virQEMUSaveDataPtr data,
+ virCommandPtr compressor,
+ unsigned int flags,
+ qemuDomainAsyncJob asyncJob);
+
+int
+virQEMUSaveDataWrite(virQEMUSaveDataPtr data,
+ int fd,
+ const char *path);
+
+virQEMUSaveDataPtr
+virQEMUSaveDataNew(char *domXML,
+ qemuDomainSaveCookiePtr cookieObj,
+ bool running,
+ int compressed,
+ virDomainXMLOptionPtr xmlopt);
+
+void
+virQEMUSaveDataFree(virQEMUSaveDataPtr data);
--
2.26.2
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