In the next patches we are going to add FreeBSD support for QEMU Guest
Agent. In the result, code in commands-posix.c will be too cumbersome.
Move Linux-specific FS freeze/thaw code to a separate file commands-linux.c
keeping common POSIX code in commands-posix.c.
Reviewed-by: Konstantin Kostiuk <kkostiuk@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
---
qga/commands-common.h | 35 +++++
qga/commands-linux.c | 286 +++++++++++++++++++++++++++++++++++++++++
qga/commands-posix.c | 289 +++---------------------------------------
qga/meson.build | 3 +
4 files changed, 340 insertions(+), 273 deletions(-)
create mode 100644 qga/commands-linux.c
diff --git a/qga/commands-common.h b/qga/commands-common.h
index d0e4a9696f..181fc330aa 100644
--- a/qga/commands-common.h
+++ b/qga/commands-common.h
@@ -10,6 +10,40 @@
#define QGA_COMMANDS_COMMON_H
#include "qga-qapi-types.h"
+#include "guest-agent-core.h"
+#include "qemu/queue.h"
+
+#if defined(__linux__)
+#include <linux/fs.h>
+#ifdef FIFREEZE
+#define CONFIG_FSFREEZE
+#endif
+#ifdef FITRIM
+#define CONFIG_FSTRIM
+#endif
+#endif /* __linux__ */
+
+#if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM)
+typedef struct FsMount {
+ char *dirname;
+ char *devtype;
+ unsigned int devmajor, devminor;
+ QTAILQ_ENTRY(FsMount) next;
+} FsMount;
+
+typedef QTAILQ_HEAD(FsMountList, FsMount) FsMountList;
+
+bool build_fs_mount_list(FsMountList *mounts, Error **errp);
+void free_fs_mount_list(FsMountList *mounts);
+#endif /* CONFIG_FSFREEZE || CONFIG_FSTRIM */
+
+#if defined(CONFIG_FSFREEZE)
+int64_t qmp_guest_fsfreeze_do_freeze_list(bool has_mountpoints,
+ strList *mountpoints,
+ FsMountList mounts,
+ Error **errp);
+int qmp_guest_fsfreeze_do_thaw(Error **errp);
+#endif /* CONFIG_FSFREEZE */
typedef struct GuestFileHandle GuestFileHandle;
@@ -29,4 +63,5 @@ GuestFileRead *guest_file_read_unsafe(GuestFileHandle *gfh,
*/
char *qga_get_host_name(Error **errp);
+void ga_wait_child(pid_t pid, int *status, Error **errp);
#endif
diff --git a/qga/commands-linux.c b/qga/commands-linux.c
new file mode 100644
index 0000000000..214e408fcd
--- /dev/null
+++ b/qga/commands-linux.c
@@ -0,0 +1,286 @@
+/*
+ * QEMU Guest Agent Linux-specific command implementations
+ *
+ * Copyright IBM Corp. 2011
+ *
+ * Authors:
+ * Michael Roth <mdroth@linux.vnet.ibm.com>
+ * Michal Privoznik <mprivozn@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "commands-common.h"
+#include "cutils.h"
+#include <mntent.h>
+#include <sys/ioctl.h>
+
+#if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM)
+static int dev_major_minor(const char *devpath,
+ unsigned int *devmajor, unsigned int *devminor)
+{
+ struct stat st;
+
+ *devmajor = 0;
+ *devminor = 0;
+
+ if (stat(devpath, &st) < 0) {
+ slog("failed to stat device file '%s': %s", devpath, strerror(errno));
+ return -1;
+ }
+ if (S_ISDIR(st.st_mode)) {
+ /* It is bind mount */
+ return -2;
+ }
+ if (S_ISBLK(st.st_mode)) {
+ *devmajor = major(st.st_rdev);
+ *devminor = minor(st.st_rdev);
+ return 0;
+ }
+ return -1;
+}
+
+static bool build_fs_mount_list_from_mtab(FsMountList *mounts, Error **errp)
+{
+ struct mntent *ment;
+ FsMount *mount;
+ char const *mtab = "/proc/self/mounts";
+ FILE *fp;
+ unsigned int devmajor, devminor;
+
+ fp = setmntent(mtab, "r");
+ if (!fp) {
+ error_setg(errp, "failed to open mtab file: '%s'", mtab);
+ return false;
+ }
+
+ while ((ment = getmntent(fp))) {
+ /*
+ * An entry which device name doesn't start with a '/' is
+ * either a dummy file system or a network file system.
+ * Add special handling for smbfs and cifs as is done by
+ * coreutils as well.
+ */
+ if ((ment->mnt_fsname[0] != '/') ||
+ (strcmp(ment->mnt_type, "smbfs") == 0) ||
+ (strcmp(ment->mnt_type, "cifs") == 0)) {
+ continue;
+ }
+ if (dev_major_minor(ment->mnt_fsname, &devmajor, &devminor) == -2) {
+ /* Skip bind mounts */
+ continue;
+ }
+
+ mount = g_new0(FsMount, 1);
+ mount->dirname = g_strdup(ment->mnt_dir);
+ mount->devtype = g_strdup(ment->mnt_type);
+ mount->devmajor = devmajor;
+ mount->devminor = devminor;
+
+ QTAILQ_INSERT_TAIL(mounts, mount, next);
+ }
+
+ endmntent(fp);
+ return true;
+}
+
+static void decode_mntname(char *name, int len)
+{
+ int i, j = 0;
+ for (i = 0; i <= len; i++) {
+ if (name[i] != '\\') {
+ name[j++] = name[i];
+ } else if (name[i + 1] == '\\') {
+ name[j++] = '\\';
+ i++;
+ } else if (name[i + 1] >= '0' && name[i + 1] <= '3' &&
+ name[i + 2] >= '0' && name[i + 2] <= '7' &&
+ name[i + 3] >= '0' && name[i + 3] <= '7') {
+ name[j++] = (name[i + 1] - '0') * 64 +
+ (name[i + 2] - '0') * 8 +
+ (name[i + 3] - '0');
+ i += 3;
+ } else {
+ name[j++] = name[i];
+ }
+ }
+}
+
+/*
+ * Walk the mount table and build a list of local file systems
+ */
+bool build_fs_mount_list(FsMountList *mounts, Error **errp)
+{
+ FsMount *mount;
+ char const *mountinfo = "/proc/self/mountinfo";
+ FILE *fp;
+ char *line = NULL, *dash;
+ size_t n;
+ char check;
+ unsigned int devmajor, devminor;
+ int ret, dir_s, dir_e, type_s, type_e, dev_s, dev_e;
+
+ fp = fopen(mountinfo, "r");
+ if (!fp) {
+ return build_fs_mount_list_from_mtab(mounts, errp);
+ }
+
+ while (getline(&line, &n, fp) != -1) {
+ ret = sscanf(line, "%*u %*u %u:%u %*s %n%*s%n%c",
+ &devmajor, &devminor, &dir_s, &dir_e, &check);
+ if (ret < 3) {
+ continue;
+ }
+ dash = strstr(line + dir_e, " - ");
+ if (!dash) {
+ continue;
+ }
+ ret = sscanf(dash, " - %n%*s%n %n%*s%n%c",
+ &type_s, &type_e, &dev_s, &dev_e, &check);
+ if (ret < 1) {
+ continue;
+ }
+ line[dir_e] = 0;
+ dash[type_e] = 0;
+ dash[dev_e] = 0;
+ decode_mntname(line + dir_s, dir_e - dir_s);
+ decode_mntname(dash + dev_s, dev_e - dev_s);
+ if (devmajor == 0) {
+ /* btrfs reports major number = 0 */
+ if (strcmp("btrfs", dash + type_s) != 0 ||
+ dev_major_minor(dash + dev_s, &devmajor, &devminor) < 0) {
+ continue;
+ }
+ }
+
+ mount = g_new0(FsMount, 1);
+ mount->dirname = g_strdup(line + dir_s);
+ mount->devtype = g_strdup(dash + type_s);
+ mount->devmajor = devmajor;
+ mount->devminor = devminor;
+
+ QTAILQ_INSERT_TAIL(mounts, mount, next);
+ }
+ free(line);
+
+ fclose(fp);
+ return true;
+}
+#endif /* CONFIG_FSFREEZE || CONFIG_FSTRIM */
+
+#ifdef CONFIG_FSFREEZE
+/*
+ * Walk list of mounted file systems in the guest, and freeze the ones which
+ * are real local file systems.
+ */
+int64_t qmp_guest_fsfreeze_do_freeze_list(bool has_mountpoints,
+ strList *mountpoints,
+ FsMountList mounts,
+ Error **errp)
+{
+ struct FsMount *mount;
+ strList *list;
+ int fd, ret, i = 0;
+
+ QTAILQ_FOREACH_REVERSE(mount, &mounts, next) {
+ /* To issue fsfreeze in the reverse order of mounts, check if the
+ * mount is listed in the list here */
+ if (has_mountpoints) {
+ for (list = mountpoints; list; list = list->next) {
+ if (strcmp(list->value, mount->dirname) == 0) {
+ break;
+ }
+ }
+ if (!list) {
+ continue;
+ }
+ }
+
+ fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
+ if (fd == -1) {
+ error_setg_errno(errp, errno, "failed to open %s", mount->dirname);
+ return -1;
+ }
+
+ /* we try to cull filesystems we know won't work in advance, but other
+ * filesystems may not implement fsfreeze for less obvious reasons.
+ * these will report EOPNOTSUPP. we simply ignore these when tallying
+ * the number of frozen filesystems.
+ * if a filesystem is mounted more than once (aka bind mount) a
+ * consecutive attempt to freeze an already frozen filesystem will
+ * return EBUSY.
+ *
+ * any other error means a failure to freeze a filesystem we
+ * expect to be freezable, so return an error in those cases
+ * and return system to thawed state.
+ */
+ ret = ioctl(fd, FIFREEZE);
+ if (ret == -1) {
+ if (errno != EOPNOTSUPP && errno != EBUSY) {
+ error_setg_errno(errp, errno, "failed to freeze %s",
+ mount->dirname);
+ close(fd);
+ return -1;
+ }
+ } else {
+ i++;
+ }
+ close(fd);
+ }
+ return i;
+}
+
+int qmp_guest_fsfreeze_do_thaw(Error **errp)
+{
+ int ret;
+ FsMountList mounts;
+ FsMount *mount;
+ int fd, i = 0, logged;
+ Error *local_err = NULL;
+
+ QTAILQ_INIT(&mounts);
+ if (!build_fs_mount_list(&mounts, &local_err)) {
+ error_propagate(errp, local_err);
+ return -1;
+ }
+
+ QTAILQ_FOREACH(mount, &mounts, next) {
+ logged = false;
+ fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
+ if (fd == -1) {
+ continue;
+ }
+ /* we have no way of knowing whether a filesystem was actually unfrozen
+ * as a result of a successful call to FITHAW, only that if an error
+ * was returned the filesystem was *not* unfrozen by that particular
+ * call.
+ *
+ * since multiple preceding FIFREEZEs require multiple calls to FITHAW
+ * to unfreeze, continuing issuing FITHAW until an error is returned,
+ * in which case either the filesystem is in an unfreezable state, or,
+ * more likely, it was thawed previously (and remains so afterward).
+ *
+ * also, since the most recent successful call is the one that did
+ * the actual unfreeze, we can use this to provide an accurate count
+ * of the number of filesystems unfrozen by guest-fsfreeze-thaw, which
+ * may * be useful for determining whether a filesystem was unfrozen
+ * during the freeze/thaw phase by a process other than qemu-ga.
+ */
+ do {
+ ret = ioctl(fd, FITHAW);
+ if (ret == 0 && !logged) {
+ i++;
+ logged = true;
+ }
+ } while (ret == 0);
+ close(fd);
+ }
+
+ free_fs_mount_list(&mounts);
+
+ return i;
+}
+#endif /* CONFIG_FSFREEZE */
diff --git a/qga/commands-posix.c b/qga/commands-posix.c
index 16d67e9f6d..9574b83c92 100644
--- a/qga/commands-posix.c
+++ b/qga/commands-posix.c
@@ -16,11 +16,9 @@
#include <sys/utsname.h>
#include <sys/wait.h>
#include <dirent.h>
-#include "guest-agent-core.h"
#include "qga-qapi-commands.h"
#include "qapi/error.h"
#include "qapi/qmp/qerror.h"
-#include "qemu/queue.h"
#include "qemu/host-utils.h"
#include "qemu/sockets.h"
#include "qemu/base64.h"
@@ -70,7 +68,7 @@
#endif
#endif
-static void ga_wait_child(pid_t pid, int *status, Error **errp)
+void ga_wait_child(pid_t pid, int *status, Error **errp)
{
pid_t rpid;
@@ -629,16 +627,7 @@ void qmp_guest_file_flush(int64_t handle, Error **errp)
#if defined(__linux__)
#if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM)
-typedef struct FsMount {
- char *dirname;
- char *devtype;
- unsigned int devmajor, devminor;
- QTAILQ_ENTRY(FsMount) next;
-} FsMount;
-
-typedef QTAILQ_HEAD(FsMountList, FsMount) FsMountList;
-
-static void free_fs_mount_list(FsMountList *mounts)
+void free_fs_mount_list(FsMountList *mounts)
{
FsMount *mount, *temp;
@@ -653,157 +642,6 @@ static void free_fs_mount_list(FsMountList *mounts)
g_free(mount);
}
}
-
-static int dev_major_minor(const char *devpath,
- unsigned int *devmajor, unsigned int *devminor)
-{
- struct stat st;
-
- *devmajor = 0;
- *devminor = 0;
-
- if (stat(devpath, &st) < 0) {
- slog("failed to stat device file '%s': %s", devpath, strerror(errno));
- return -1;
- }
- if (S_ISDIR(st.st_mode)) {
- /* It is bind mount */
- return -2;
- }
- if (S_ISBLK(st.st_mode)) {
- *devmajor = major(st.st_rdev);
- *devminor = minor(st.st_rdev);
- return 0;
- }
- return -1;
-}
-
-/*
- * Walk the mount table and build a list of local file systems
- */
-static bool build_fs_mount_list_from_mtab(FsMountList *mounts, Error **errp)
-{
- struct mntent *ment;
- FsMount *mount;
- char const *mtab = "/proc/self/mounts";
- FILE *fp;
- unsigned int devmajor, devminor;
-
- fp = setmntent(mtab, "r");
- if (!fp) {
- error_setg(errp, "failed to open mtab file: '%s'", mtab);
- return false;
- }
-
- while ((ment = getmntent(fp))) {
- /*
- * An entry which device name doesn't start with a '/' is
- * either a dummy file system or a network file system.
- * Add special handling for smbfs and cifs as is done by
- * coreutils as well.
- */
- if ((ment->mnt_fsname[0] != '/') ||
- (strcmp(ment->mnt_type, "smbfs") == 0) ||
- (strcmp(ment->mnt_type, "cifs") == 0)) {
- continue;
- }
- if (dev_major_minor(ment->mnt_fsname, &devmajor, &devminor) == -2) {
- /* Skip bind mounts */
- continue;
- }
-
- mount = g_new0(FsMount, 1);
- mount->dirname = g_strdup(ment->mnt_dir);
- mount->devtype = g_strdup(ment->mnt_type);
- mount->devmajor = devmajor;
- mount->devminor = devminor;
-
- QTAILQ_INSERT_TAIL(mounts, mount, next);
- }
-
- endmntent(fp);
- return true;
-}
-
-static void decode_mntname(char *name, int len)
-{
- int i, j = 0;
- for (i = 0; i <= len; i++) {
- if (name[i] != '\\') {
- name[j++] = name[i];
- } else if (name[i + 1] == '\\') {
- name[j++] = '\\';
- i++;
- } else if (name[i + 1] >= '0' && name[i + 1] <= '3' &&
- name[i + 2] >= '0' && name[i + 2] <= '7' &&
- name[i + 3] >= '0' && name[i + 3] <= '7') {
- name[j++] = (name[i + 1] - '0') * 64 +
- (name[i + 2] - '0') * 8 +
- (name[i + 3] - '0');
- i += 3;
- } else {
- name[j++] = name[i];
- }
- }
-}
-
-static bool build_fs_mount_list(FsMountList *mounts, Error **errp)
-{
- FsMount *mount;
- char const *mountinfo = "/proc/self/mountinfo";
- FILE *fp;
- char *line = NULL, *dash;
- size_t n;
- char check;
- unsigned int devmajor, devminor;
- int ret, dir_s, dir_e, type_s, type_e, dev_s, dev_e;
-
- fp = fopen(mountinfo, "r");
- if (!fp) {
- return build_fs_mount_list_from_mtab(mounts, errp);
- }
-
- while (getline(&line, &n, fp) != -1) {
- ret = sscanf(line, "%*u %*u %u:%u %*s %n%*s%n%c",
- &devmajor, &devminor, &dir_s, &dir_e, &check);
- if (ret < 3) {
- continue;
- }
- dash = strstr(line + dir_e, " - ");
- if (!dash) {
- continue;
- }
- ret = sscanf(dash, " - %n%*s%n %n%*s%n%c",
- &type_s, &type_e, &dev_s, &dev_e, &check);
- if (ret < 1) {
- continue;
- }
- line[dir_e] = 0;
- dash[type_e] = 0;
- dash[dev_e] = 0;
- decode_mntname(line + dir_s, dir_e - dir_s);
- decode_mntname(dash + dev_s, dev_e - dev_s);
- if (devmajor == 0) {
- /* btrfs reports major number = 0 */
- if (strcmp("btrfs", dash + type_s) != 0 ||
- dev_major_minor(dash + dev_s, &devmajor, &devminor) < 0) {
- continue;
- }
- }
-
- mount = g_new0(FsMount, 1);
- mount->dirname = g_strdup(line + dir_s);
- mount->devtype = g_strdup(dash + type_s);
- mount->devmajor = devmajor;
- mount->devminor = devminor;
-
- QTAILQ_INSERT_TAIL(mounts, mount, next);
- }
- free(line);
-
- fclose(fp);
- return true;
-}
#endif
#if defined(CONFIG_FSFREEZE)
@@ -1708,20 +1546,13 @@ int64_t qmp_guest_fsfreeze_freeze(Error **errp)
return qmp_guest_fsfreeze_freeze_list(false, NULL, errp);
}
-/*
- * Walk list of mounted file systems in the guest, and freeze the ones which
- * are real local file systems.
- */
int64_t qmp_guest_fsfreeze_freeze_list(bool has_mountpoints,
strList *mountpoints,
Error **errp)
{
- int ret = 0, i = 0;
- strList *list;
+ int ret;
FsMountList mounts;
- struct FsMount *mount;
Error *local_err = NULL;
- int fd;
slog("guest-fsfreeze called");
@@ -1740,122 +1571,34 @@ int64_t qmp_guest_fsfreeze_freeze_list(bool has_mountpoints,
/* cannot risk guest agent blocking itself on a write in this state */
ga_set_frozen(ga_state);
- QTAILQ_FOREACH_REVERSE(mount, &mounts, next) {
- /* To issue fsfreeze in the reverse order of mounts, check if the
- * mount is listed in the list here */
- if (has_mountpoints) {
- for (list = mountpoints; list; list = list->next) {
- if (strcmp(list->value, mount->dirname) == 0) {
- break;
- }
- }
- if (!list) {
- continue;
- }
- }
-
- fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
- if (fd == -1) {
- error_setg_errno(errp, errno, "failed to open %s", mount->dirname);
- goto error;
- }
-
- /* we try to cull filesystems we know won't work in advance, but other
- * filesystems may not implement fsfreeze for less obvious reasons.
- * these will report EOPNOTSUPP. we simply ignore these when tallying
- * the number of frozen filesystems.
- * if a filesystem is mounted more than once (aka bind mount) a
- * consecutive attempt to freeze an already frozen filesystem will
- * return EBUSY.
- *
- * any other error means a failure to freeze a filesystem we
- * expect to be freezable, so return an error in those cases
- * and return system to thawed state.
- */
- ret = ioctl(fd, FIFREEZE);
- if (ret == -1) {
- if (errno != EOPNOTSUPP && errno != EBUSY) {
- error_setg_errno(errp, errno, "failed to freeze %s",
- mount->dirname);
- close(fd);
- goto error;
- }
- } else {
- i++;
- }
- close(fd);
- }
+ ret = qmp_guest_fsfreeze_do_freeze_list(has_mountpoints, mountpoints,
+ mounts, errp);
free_fs_mount_list(&mounts);
/* We may not issue any FIFREEZE here.
* Just unset ga_state here and ready for the next call.
*/
- if (i == 0) {
+ if (ret == 0) {
ga_unset_frozen(ga_state);
+ } else if (ret < 0) {
+ qmp_guest_fsfreeze_thaw(NULL);
}
- return i;
-
-error:
- free_fs_mount_list(&mounts);
- qmp_guest_fsfreeze_thaw(NULL);
- return 0;
+ return ret;
}
-/*
- * Walk list of frozen file systems in the guest, and thaw them.
- */
int64_t qmp_guest_fsfreeze_thaw(Error **errp)
{
int ret;
- FsMountList mounts;
- FsMount *mount;
- int fd, i = 0, logged;
- Error *local_err = NULL;
- QTAILQ_INIT(&mounts);
- if (!build_fs_mount_list(&mounts, &local_err)) {
- error_propagate(errp, local_err);
- return 0;
+ ret = qmp_guest_fsfreeze_do_thaw(errp);
+ if (ret >= 0) {
+ ga_unset_frozen(ga_state);
+ execute_fsfreeze_hook(FSFREEZE_HOOK_THAW, errp);
+ } else {
+ ret = 0;
}
- QTAILQ_FOREACH(mount, &mounts, next) {
- logged = false;
- fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
- if (fd == -1) {
- continue;
- }
- /* we have no way of knowing whether a filesystem was actually unfrozen
- * as a result of a successful call to FITHAW, only that if an error
- * was returned the filesystem was *not* unfrozen by that particular
- * call.
- *
- * since multiple preceding FIFREEZEs require multiple calls to FITHAW
- * to unfreeze, continuing issuing FITHAW until an error is returned,
- * in which case either the filesystem is in an unfreezable state, or,
- * more likely, it was thawed previously (and remains so afterward).
- *
- * also, since the most recent successful call is the one that did
- * the actual unfreeze, we can use this to provide an accurate count
- * of the number of filesystems unfrozen by guest-fsfreeze-thaw, which
- * may * be useful for determining whether a filesystem was unfrozen
- * during the freeze/thaw phase by a process other than qemu-ga.
- */
- do {
- ret = ioctl(fd, FITHAW);
- if (ret == 0 && !logged) {
- i++;
- logged = true;
- }
- } while (ret == 0);
- close(fd);
- }
-
- ga_unset_frozen(ga_state);
- free_fs_mount_list(&mounts);
-
- execute_fsfreeze_hook(FSFREEZE_HOOK_THAW, errp);
-
- return i;
+ return ret;
}
static void guest_fsfreeze_cleanup(void)
diff --git a/qga/meson.build b/qga/meson.build
index a0ffd6d268..932b4e7ca8 100644
--- a/qga/meson.build
+++ b/qga/meson.build
@@ -72,6 +72,9 @@ qga_ss.add(when: 'CONFIG_POSIX', if_true: files(
'commands-posix.c',
'commands-posix-ssh.c',
))
+qga_ss.add(when: 'CONFIG_LINUX', if_true: files(
+ 'commands-linux.c',
+))
qga_ss.add(when: 'CONFIG_WIN32', if_true: files(
'channel-win32.c',
'commands-win32.c',
--
2.34.1
Hi
On Thu, Oct 13, 2022 at 1:23 PM Alexander Ivanov <
alexander.ivanov@virtuozzo.com> wrote:
> In the next patches we are going to add FreeBSD support for QEMU Guest
> Agent. In the result, code in commands-posix.c will be too cumbersome.
>
> Move Linux-specific FS freeze/thaw code to a separate file commands-linux.c
> keeping common POSIX code in commands-posix.c.
>
> Reviewed-by: Konstantin Kostiuk <kkostiuk@redhat.com>
> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
> ---
> qga/commands-common.h | 35 +++++
> qga/commands-linux.c | 286 +++++++++++++++++++++++++++++++++++++++++
> qga/commands-posix.c | 289 +++---------------------------------------
> qga/meson.build | 3 +
> 4 files changed, 340 insertions(+), 273 deletions(-)
> create mode 100644 qga/commands-linux.c
>
> diff --git a/qga/commands-common.h b/qga/commands-common.h
> index d0e4a9696f..181fc330aa 100644
> --- a/qga/commands-common.h
> +++ b/qga/commands-common.h
> @@ -10,6 +10,40 @@
> #define QGA_COMMANDS_COMMON_H
>
> #include "qga-qapi-types.h"
> +#include "guest-agent-core.h"
> +#include "qemu/queue.h"
> +
> +#if defined(__linux__)
> +#include <linux/fs.h>
> +#ifdef FIFREEZE
> +#define CONFIG_FSFREEZE
> +#endif
> +#ifdef FITRIM
> +#define CONFIG_FSTRIM
> +#endif
> +#endif /* __linux__ */
> +
> +#if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM)
> +typedef struct FsMount {
> + char *dirname;
> + char *devtype;
> + unsigned int devmajor, devminor;
> + QTAILQ_ENTRY(FsMount) next;
> +} FsMount;
> +
> +typedef QTAILQ_HEAD(FsMountList, FsMount) FsMountList;
> +
> +bool build_fs_mount_list(FsMountList *mounts, Error **errp);
> +void free_fs_mount_list(FsMountList *mounts);
> +#endif /* CONFIG_FSFREEZE || CONFIG_FSTRIM */
> +
> +#if defined(CONFIG_FSFREEZE)
> +int64_t qmp_guest_fsfreeze_do_freeze_list(bool has_mountpoints,
> + strList *mountpoints,
> + FsMountList mounts,
> + Error **errp);
> +int qmp_guest_fsfreeze_do_thaw(Error **errp);
> +#endif /* CONFIG_FSFREEZE */
>
> typedef struct GuestFileHandle GuestFileHandle;
>
> @@ -29,4 +63,5 @@ GuestFileRead *guest_file_read_unsafe(GuestFileHandle
> *gfh,
> */
> char *qga_get_host_name(Error **errp);
>
> +void ga_wait_child(pid_t pid, int *status, Error **errp);
>
This doesn't belong here, afaict.
> #endif
> diff --git a/qga/commands-linux.c b/qga/commands-linux.c
> new file mode 100644
> index 0000000000..214e408fcd
> --- /dev/null
> +++ b/qga/commands-linux.c
> @@ -0,0 +1,286 @@
> +/*
> + * QEMU Guest Agent Linux-specific command implementations
> + *
> + * Copyright IBM Corp. 2011
> + *
> + * Authors:
> + * Michael Roth <mdroth@linux.vnet.ibm.com>
> + * Michal Privoznik <mprivozn@redhat.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or
> later.
> + * See the COPYING file in the top-level directory.
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qapi/error.h"
> +#include "commands-common.h"
> +#include "cutils.h"
> +#include <mntent.h>
> +#include <sys/ioctl.h>
> +
> +#if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM)
> +static int dev_major_minor(const char *devpath,
> + unsigned int *devmajor, unsigned int *devminor)
> +{
> + struct stat st;
> +
> + *devmajor = 0;
> + *devminor = 0;
> +
> + if (stat(devpath, &st) < 0) {
> + slog("failed to stat device file '%s': %s", devpath,
> strerror(errno));
> + return -1;
> + }
> + if (S_ISDIR(st.st_mode)) {
> + /* It is bind mount */
> + return -2;
> + }
> + if (S_ISBLK(st.st_mode)) {
> + *devmajor = major(st.st_rdev);
> + *devminor = minor(st.st_rdev);
> + return 0;
> + }
> + return -1;
> +}
> +
> +static bool build_fs_mount_list_from_mtab(FsMountList *mounts, Error
> **errp)
> +{
> + struct mntent *ment;
> + FsMount *mount;
> + char const *mtab = "/proc/self/mounts";
> + FILE *fp;
> + unsigned int devmajor, devminor;
> +
> + fp = setmntent(mtab, "r");
> + if (!fp) {
> + error_setg(errp, "failed to open mtab file: '%s'", mtab);
> + return false;
> + }
> +
> + while ((ment = getmntent(fp))) {
> + /*
> + * An entry which device name doesn't start with a '/' is
> + * either a dummy file system or a network file system.
> + * Add special handling for smbfs and cifs as is done by
> + * coreutils as well.
> + */
> + if ((ment->mnt_fsname[0] != '/') ||
> + (strcmp(ment->mnt_type, "smbfs") == 0) ||
> + (strcmp(ment->mnt_type, "cifs") == 0)) {
> + continue;
> + }
> + if (dev_major_minor(ment->mnt_fsname, &devmajor, &devminor) ==
> -2) {
> + /* Skip bind mounts */
> + continue;
> + }
> +
> + mount = g_new0(FsMount, 1);
> + mount->dirname = g_strdup(ment->mnt_dir);
> + mount->devtype = g_strdup(ment->mnt_type);
> + mount->devmajor = devmajor;
> + mount->devminor = devminor;
> +
> + QTAILQ_INSERT_TAIL(mounts, mount, next);
> + }
> +
> + endmntent(fp);
> + return true;
> +}
> +
> +static void decode_mntname(char *name, int len)
> +{
> + int i, j = 0;
> + for (i = 0; i <= len; i++) {
> + if (name[i] != '\\') {
> + name[j++] = name[i];
> + } else if (name[i + 1] == '\\') {
> + name[j++] = '\\';
> + i++;
> + } else if (name[i + 1] >= '0' && name[i + 1] <= '3' &&
> + name[i + 2] >= '0' && name[i + 2] <= '7' &&
> + name[i + 3] >= '0' && name[i + 3] <= '7') {
> + name[j++] = (name[i + 1] - '0') * 64 +
> + (name[i + 2] - '0') * 8 +
> + (name[i + 3] - '0');
> + i += 3;
> + } else {
> + name[j++] = name[i];
> + }
> + }
> +}
> +
> +/*
> + * Walk the mount table and build a list of local file systems
> + */
> +bool build_fs_mount_list(FsMountList *mounts, Error **errp)
> +{
> + FsMount *mount;
> + char const *mountinfo = "/proc/self/mountinfo";
> + FILE *fp;
> + char *line = NULL, *dash;
> + size_t n;
> + char check;
> + unsigned int devmajor, devminor;
> + int ret, dir_s, dir_e, type_s, type_e, dev_s, dev_e;
> +
> + fp = fopen(mountinfo, "r");
> + if (!fp) {
> + return build_fs_mount_list_from_mtab(mounts, errp);
> + }
> +
> + while (getline(&line, &n, fp) != -1) {
> + ret = sscanf(line, "%*u %*u %u:%u %*s %n%*s%n%c",
> + &devmajor, &devminor, &dir_s, &dir_e, &check);
> + if (ret < 3) {
> + continue;
> + }
> + dash = strstr(line + dir_e, " - ");
> + if (!dash) {
> + continue;
> + }
> + ret = sscanf(dash, " - %n%*s%n %n%*s%n%c",
> + &type_s, &type_e, &dev_s, &dev_e, &check);
> + if (ret < 1) {
> + continue;
> + }
> + line[dir_e] = 0;
> + dash[type_e] = 0;
> + dash[dev_e] = 0;
> + decode_mntname(line + dir_s, dir_e - dir_s);
> + decode_mntname(dash + dev_s, dev_e - dev_s);
> + if (devmajor == 0) {
> + /* btrfs reports major number = 0 */
> + if (strcmp("btrfs", dash + type_s) != 0 ||
> + dev_major_minor(dash + dev_s, &devmajor, &devminor) < 0) {
> + continue;
> + }
> + }
> +
> + mount = g_new0(FsMount, 1);
> + mount->dirname = g_strdup(line + dir_s);
> + mount->devtype = g_strdup(dash + type_s);
> + mount->devmajor = devmajor;
> + mount->devminor = devminor;
> +
> + QTAILQ_INSERT_TAIL(mounts, mount, next);
> + }
> + free(line);
> +
> + fclose(fp);
> + return true;
> +}
> +#endif /* CONFIG_FSFREEZE || CONFIG_FSTRIM */
> +
> +#ifdef CONFIG_FSFREEZE
> +/*
> + * Walk list of mounted file systems in the guest, and freeze the ones
> which
> + * are real local file systems.
> + */
> +int64_t qmp_guest_fsfreeze_do_freeze_list(bool has_mountpoints,
> + strList *mountpoints,
> + FsMountList mounts,
> + Error **errp)
> +{
> + struct FsMount *mount;
> + strList *list;
> + int fd, ret, i = 0;
> +
> + QTAILQ_FOREACH_REVERSE(mount, &mounts, next) {
> + /* To issue fsfreeze in the reverse order of mounts, check if the
> + * mount is listed in the list here */
> + if (has_mountpoints) {
> + for (list = mountpoints; list; list = list->next) {
> + if (strcmp(list->value, mount->dirname) == 0) {
> + break;
> + }
> + }
> + if (!list) {
> + continue;
> + }
> + }
> +
> + fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
> + if (fd == -1) {
> + error_setg_errno(errp, errno, "failed to open %s",
> mount->dirname);
> + return -1;
> + }
> +
> + /* we try to cull filesystems we know won't work in advance, but
> other
> + * filesystems may not implement fsfreeze for less obvious
> reasons.
> + * these will report EOPNOTSUPP. we simply ignore these when
> tallying
> + * the number of frozen filesystems.
> + * if a filesystem is mounted more than once (aka bind mount) a
> + * consecutive attempt to freeze an already frozen filesystem will
> + * return EBUSY.
> + *
> + * any other error means a failure to freeze a filesystem we
> + * expect to be freezable, so return an error in those cases
> + * and return system to thawed state.
> + */
> + ret = ioctl(fd, FIFREEZE);
> + if (ret == -1) {
> + if (errno != EOPNOTSUPP && errno != EBUSY) {
> + error_setg_errno(errp, errno, "failed to freeze %s",
> + mount->dirname);
> + close(fd);
> + return -1;
> + }
> + } else {
> + i++;
> + }
> + close(fd);
> + }
> + return i;
> +}
> +
> +int qmp_guest_fsfreeze_do_thaw(Error **errp)
> +{
> + int ret;
> + FsMountList mounts;
> + FsMount *mount;
> + int fd, i = 0, logged;
> + Error *local_err = NULL;
> +
> + QTAILQ_INIT(&mounts);
> + if (!build_fs_mount_list(&mounts, &local_err)) {
> + error_propagate(errp, local_err);
> + return -1;
> + }
> +
> + QTAILQ_FOREACH(mount, &mounts, next) {
> + logged = false;
> + fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
> + if (fd == -1) {
> + continue;
> + }
> + /* we have no way of knowing whether a filesystem was actually
> unfrozen
> + * as a result of a successful call to FITHAW, only that if an
> error
> + * was returned the filesystem was *not* unfrozen by that
> particular
> + * call.
> + *
> + * since multiple preceding FIFREEZEs require multiple calls to
> FITHAW
> + * to unfreeze, continuing issuing FITHAW until an error is
> returned,
> + * in which case either the filesystem is in an unfreezable
> state, or,
> + * more likely, it was thawed previously (and remains so
> afterward).
> + *
> + * also, since the most recent successful call is the one that did
> + * the actual unfreeze, we can use this to provide an accurate
> count
> + * of the number of filesystems unfrozen by guest-fsfreeze-thaw,
> which
> + * may * be useful for determining whether a filesystem was
> unfrozen
> + * during the freeze/thaw phase by a process other than qemu-ga.
> + */
> + do {
> + ret = ioctl(fd, FITHAW);
> + if (ret == 0 && !logged) {
> + i++;
> + logged = true;
> + }
> + } while (ret == 0);
> + close(fd);
> + }
> +
> + free_fs_mount_list(&mounts);
> +
> + return i;
> +}
> +#endif /* CONFIG_FSFREEZE */
> diff --git a/qga/commands-posix.c b/qga/commands-posix.c
> index 16d67e9f6d..9574b83c92 100644
> --- a/qga/commands-posix.c
> +++ b/qga/commands-posix.c
> @@ -16,11 +16,9 @@
> #include <sys/utsname.h>
> #include <sys/wait.h>
> #include <dirent.h>
> -#include "guest-agent-core.h"
> #include "qga-qapi-commands.h"
> #include "qapi/error.h"
> #include "qapi/qmp/qerror.h"
> -#include "qemu/queue.h"
> #include "qemu/host-utils.h"
> #include "qemu/sockets.h"
> #include "qemu/base64.h"
> @@ -70,7 +68,7 @@
> #endif
> #endif
>
> -static void ga_wait_child(pid_t pid, int *status, Error **errp)
> +void ga_wait_child(pid_t pid, int *status, Error **errp)
> {
> pid_t rpid;
>
> @@ -629,16 +627,7 @@ void qmp_guest_file_flush(int64_t handle, Error
> **errp)
> #if defined(__linux__)
>
> #if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM)
> -typedef struct FsMount {
> - char *dirname;
> - char *devtype;
> - unsigned int devmajor, devminor;
> - QTAILQ_ENTRY(FsMount) next;
> -} FsMount;
> -
> -typedef QTAILQ_HEAD(FsMountList, FsMount) FsMountList;
> -
> -static void free_fs_mount_list(FsMountList *mounts)
> +void free_fs_mount_list(FsMountList *mounts)
> {
> FsMount *mount, *temp;
>
> @@ -653,157 +642,6 @@ static void free_fs_mount_list(FsMountList *mounts)
> g_free(mount);
> }
> }
> -
> -static int dev_major_minor(const char *devpath,
> - unsigned int *devmajor, unsigned int *devminor)
> -{
> - struct stat st;
> -
> - *devmajor = 0;
> - *devminor = 0;
> -
> - if (stat(devpath, &st) < 0) {
> - slog("failed to stat device file '%s': %s", devpath,
> strerror(errno));
> - return -1;
> - }
> - if (S_ISDIR(st.st_mode)) {
> - /* It is bind mount */
> - return -2;
> - }
> - if (S_ISBLK(st.st_mode)) {
> - *devmajor = major(st.st_rdev);
> - *devminor = minor(st.st_rdev);
> - return 0;
> - }
> - return -1;
> -}
> -
> -/*
> - * Walk the mount table and build a list of local file systems
> - */
> -static bool build_fs_mount_list_from_mtab(FsMountList *mounts, Error
> **errp)
> -{
> - struct mntent *ment;
> - FsMount *mount;
> - char const *mtab = "/proc/self/mounts";
> - FILE *fp;
> - unsigned int devmajor, devminor;
> -
> - fp = setmntent(mtab, "r");
> - if (!fp) {
> - error_setg(errp, "failed to open mtab file: '%s'", mtab);
> - return false;
> - }
> -
> - while ((ment = getmntent(fp))) {
> - /*
> - * An entry which device name doesn't start with a '/' is
> - * either a dummy file system or a network file system.
> - * Add special handling for smbfs and cifs as is done by
> - * coreutils as well.
> - */
> - if ((ment->mnt_fsname[0] != '/') ||
> - (strcmp(ment->mnt_type, "smbfs") == 0) ||
> - (strcmp(ment->mnt_type, "cifs") == 0)) {
> - continue;
> - }
> - if (dev_major_minor(ment->mnt_fsname, &devmajor, &devminor) ==
> -2) {
> - /* Skip bind mounts */
> - continue;
> - }
> -
> - mount = g_new0(FsMount, 1);
> - mount->dirname = g_strdup(ment->mnt_dir);
> - mount->devtype = g_strdup(ment->mnt_type);
> - mount->devmajor = devmajor;
> - mount->devminor = devminor;
> -
> - QTAILQ_INSERT_TAIL(mounts, mount, next);
> - }
> -
> - endmntent(fp);
> - return true;
> -}
> -
> -static void decode_mntname(char *name, int len)
> -{
> - int i, j = 0;
> - for (i = 0; i <= len; i++) {
> - if (name[i] != '\\') {
> - name[j++] = name[i];
> - } else if (name[i + 1] == '\\') {
> - name[j++] = '\\';
> - i++;
> - } else if (name[i + 1] >= '0' && name[i + 1] <= '3' &&
> - name[i + 2] >= '0' && name[i + 2] <= '7' &&
> - name[i + 3] >= '0' && name[i + 3] <= '7') {
> - name[j++] = (name[i + 1] - '0') * 64 +
> - (name[i + 2] - '0') * 8 +
> - (name[i + 3] - '0');
> - i += 3;
> - } else {
> - name[j++] = name[i];
> - }
> - }
> -}
> -
> -static bool build_fs_mount_list(FsMountList *mounts, Error **errp)
> -{
> - FsMount *mount;
> - char const *mountinfo = "/proc/self/mountinfo";
> - FILE *fp;
> - char *line = NULL, *dash;
> - size_t n;
> - char check;
> - unsigned int devmajor, devminor;
> - int ret, dir_s, dir_e, type_s, type_e, dev_s, dev_e;
> -
> - fp = fopen(mountinfo, "r");
> - if (!fp) {
> - return build_fs_mount_list_from_mtab(mounts, errp);
> - }
> -
> - while (getline(&line, &n, fp) != -1) {
> - ret = sscanf(line, "%*u %*u %u:%u %*s %n%*s%n%c",
> - &devmajor, &devminor, &dir_s, &dir_e, &check);
> - if (ret < 3) {
> - continue;
> - }
> - dash = strstr(line + dir_e, " - ");
> - if (!dash) {
> - continue;
> - }
> - ret = sscanf(dash, " - %n%*s%n %n%*s%n%c",
> - &type_s, &type_e, &dev_s, &dev_e, &check);
> - if (ret < 1) {
> - continue;
> - }
> - line[dir_e] = 0;
> - dash[type_e] = 0;
> - dash[dev_e] = 0;
> - decode_mntname(line + dir_s, dir_e - dir_s);
> - decode_mntname(dash + dev_s, dev_e - dev_s);
> - if (devmajor == 0) {
> - /* btrfs reports major number = 0 */
> - if (strcmp("btrfs", dash + type_s) != 0 ||
> - dev_major_minor(dash + dev_s, &devmajor, &devminor) < 0) {
> - continue;
> - }
> - }
> -
> - mount = g_new0(FsMount, 1);
> - mount->dirname = g_strdup(line + dir_s);
> - mount->devtype = g_strdup(dash + type_s);
> - mount->devmajor = devmajor;
> - mount->devminor = devminor;
> -
> - QTAILQ_INSERT_TAIL(mounts, mount, next);
> - }
> - free(line);
> -
> - fclose(fp);
> - return true;
> -}
> #endif
>
> #if defined(CONFIG_FSFREEZE)
> @@ -1708,20 +1546,13 @@ int64_t qmp_guest_fsfreeze_freeze(Error **errp)
> return qmp_guest_fsfreeze_freeze_list(false, NULL, errp);
> }
>
> -/*
> - * Walk list of mounted file systems in the guest, and freeze the ones
> which
> - * are real local file systems.
> - */
> int64_t qmp_guest_fsfreeze_freeze_list(bool has_mountpoints,
> strList *mountpoints,
> Error **errp)
> {
> - int ret = 0, i = 0;
> - strList *list;
> + int ret;
> FsMountList mounts;
> - struct FsMount *mount;
> Error *local_err = NULL;
> - int fd;
>
> slog("guest-fsfreeze called");
>
> @@ -1740,122 +1571,34 @@ int64_t qmp_guest_fsfreeze_freeze_list(bool
> has_mountpoints,
> /* cannot risk guest agent blocking itself on a write in this state */
> ga_set_frozen(ga_state);
>
> - QTAILQ_FOREACH_REVERSE(mount, &mounts, next) {
> - /* To issue fsfreeze in the reverse order of mounts, check if the
> - * mount is listed in the list here */
> - if (has_mountpoints) {
> - for (list = mountpoints; list; list = list->next) {
> - if (strcmp(list->value, mount->dirname) == 0) {
> - break;
> - }
> - }
> - if (!list) {
> - continue;
> - }
> - }
> -
> - fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
> - if (fd == -1) {
> - error_setg_errno(errp, errno, "failed to open %s",
> mount->dirname);
> - goto error;
> - }
> -
> - /* we try to cull filesystems we know won't work in advance, but
> other
> - * filesystems may not implement fsfreeze for less obvious
> reasons.
> - * these will report EOPNOTSUPP. we simply ignore these when
> tallying
> - * the number of frozen filesystems.
> - * if a filesystem is mounted more than once (aka bind mount) a
> - * consecutive attempt to freeze an already frozen filesystem will
> - * return EBUSY.
> - *
> - * any other error means a failure to freeze a filesystem we
> - * expect to be freezable, so return an error in those cases
> - * and return system to thawed state.
> - */
> - ret = ioctl(fd, FIFREEZE);
> - if (ret == -1) {
> - if (errno != EOPNOTSUPP && errno != EBUSY) {
> - error_setg_errno(errp, errno, "failed to freeze %s",
> - mount->dirname);
> - close(fd);
> - goto error;
> - }
> - } else {
> - i++;
> - }
> - close(fd);
> - }
> + ret = qmp_guest_fsfreeze_do_freeze_list(has_mountpoints, mountpoints,
> + mounts, errp);
>
> free_fs_mount_list(&mounts);
> /* We may not issue any FIFREEZE here.
> * Just unset ga_state here and ready for the next call.
> */
> - if (i == 0) {
> + if (ret == 0) {
> ga_unset_frozen(ga_state);
> + } else if (ret < 0) {
> + qmp_guest_fsfreeze_thaw(NULL);
> }
> - return i;
> -
> -error:
> - free_fs_mount_list(&mounts);
> - qmp_guest_fsfreeze_thaw(NULL);
> - return 0;
> + return ret;
> }
>
> -/*
> - * Walk list of frozen file systems in the guest, and thaw them.
> - */
> int64_t qmp_guest_fsfreeze_thaw(Error **errp)
> {
> int ret;
> - FsMountList mounts;
> - FsMount *mount;
> - int fd, i = 0, logged;
> - Error *local_err = NULL;
>
> - QTAILQ_INIT(&mounts);
> - if (!build_fs_mount_list(&mounts, &local_err)) {
> - error_propagate(errp, local_err);
> - return 0;
> + ret = qmp_guest_fsfreeze_do_thaw(errp);
> + if (ret >= 0) {
> + ga_unset_frozen(ga_state);
> + execute_fsfreeze_hook(FSFREEZE_HOOK_THAW, errp);
> + } else {
> + ret = 0;
> }
>
> - QTAILQ_FOREACH(mount, &mounts, next) {
> - logged = false;
> - fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
> - if (fd == -1) {
> - continue;
> - }
> - /* we have no way of knowing whether a filesystem was actually
> unfrozen
> - * as a result of a successful call to FITHAW, only that if an
> error
> - * was returned the filesystem was *not* unfrozen by that
> particular
> - * call.
> - *
> - * since multiple preceding FIFREEZEs require multiple calls to
> FITHAW
> - * to unfreeze, continuing issuing FITHAW until an error is
> returned,
> - * in which case either the filesystem is in an unfreezable
> state, or,
> - * more likely, it was thawed previously (and remains so
> afterward).
> - *
> - * also, since the most recent successful call is the one that did
> - * the actual unfreeze, we can use this to provide an accurate
> count
> - * of the number of filesystems unfrozen by guest-fsfreeze-thaw,
> which
> - * may * be useful for determining whether a filesystem was
> unfrozen
> - * during the freeze/thaw phase by a process other than qemu-ga.
> - */
> - do {
> - ret = ioctl(fd, FITHAW);
> - if (ret == 0 && !logged) {
> - i++;
> - logged = true;
> - }
> - } while (ret == 0);
> - close(fd);
> - }
> -
> - ga_unset_frozen(ga_state);
> - free_fs_mount_list(&mounts);
> -
> - execute_fsfreeze_hook(FSFREEZE_HOOK_THAW, errp);
> -
> - return i;
> + return ret;
> }
>
> static void guest_fsfreeze_cleanup(void)
> diff --git a/qga/meson.build b/qga/meson.build
> index a0ffd6d268..932b4e7ca8 100644
> --- a/qga/meson.build
> +++ b/qga/meson.build
> @@ -72,6 +72,9 @@ qga_ss.add(when: 'CONFIG_POSIX', if_true: files(
> 'commands-posix.c',
> 'commands-posix-ssh.c',
> ))
> +qga_ss.add(when: 'CONFIG_LINUX', if_true: files(
> + 'commands-linux.c',
> +))
> qga_ss.add(when: 'CONFIG_WIN32', if_true: files(
> 'channel-win32.c',
> 'commands-win32.c',
> --
> 2.34.1
>
>
--
Marc-André Lureau
Hi
On 13.10.2022 14:10, Marc-André Lureau wrote:
> Hi
>
> On Thu, Oct 13, 2022 at 1:23 PM Alexander Ivanov
> <alexander.ivanov@virtuozzo.com> wrote:
>
> In the next patches we are going to add FreeBSD support for QEMU Guest
> Agent. In the result, code in commands-posix.c will be too cumbersome.
>
> Move Linux-specific FS freeze/thaw code to a separate file
> commands-linux.c
> keeping common POSIX code in commands-posix.c.
>
> Reviewed-by: Konstantin Kostiuk <kkostiuk@redhat.com>
> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
> Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
> ---
> qga/commands-common.h | 35 +++++
> qga/commands-linux.c | 286 +++++++++++++++++++++++++++++++++++++++++
> qga/commands-posix.c | 289
> +++---------------------------------------
> qga/meson.build | 3 +
> 4 files changed, 340 insertions(+), 273 deletions(-)
> create mode 100644 qga/commands-linux.c
>
> diff --git a/qga/commands-common.h b/qga/commands-common.h
> index d0e4a9696f..181fc330aa 100644
> --- a/qga/commands-common.h
> +++ b/qga/commands-common.h
> @@ -10,6 +10,40 @@
> #define QGA_COMMANDS_COMMON_H
>
> #include "qga-qapi-types.h"
> +#include "guest-agent-core.h"
> +#include "qemu/queue.h"
> +
> +#if defined(__linux__)
> +#include <linux/fs.h>
> +#ifdef FIFREEZE
> +#define CONFIG_FSFREEZE
> +#endif
> +#ifdef FITRIM
> +#define CONFIG_FSTRIM
> +#endif
> +#endif /* __linux__ */
> +
> +#if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM)
> +typedef struct FsMount {
> + char *dirname;
> + char *devtype;
> + unsigned int devmajor, devminor;
> + QTAILQ_ENTRY(FsMount) next;
> +} FsMount;
> +
> +typedef QTAILQ_HEAD(FsMountList, FsMount) FsMountList;
> +
> +bool build_fs_mount_list(FsMountList *mounts, Error **errp);
> +void free_fs_mount_list(FsMountList *mounts);
> +#endif /* CONFIG_FSFREEZE || CONFIG_FSTRIM */
> +
> +#if defined(CONFIG_FSFREEZE)
> +int64_t qmp_guest_fsfreeze_do_freeze_list(bool has_mountpoints,
> + strList *mountpoints,
> + FsMountList mounts,
> + Error **errp);
> +int qmp_guest_fsfreeze_do_thaw(Error **errp);
> +#endif /* CONFIG_FSFREEZE */
>
> typedef struct GuestFileHandle GuestFileHandle;
>
> @@ -29,4 +63,5 @@ GuestFileRead
> *guest_file_read_unsafe(GuestFileHandle *gfh,
> */
> char *qga_get_host_name(Error **errp);
>
> +void ga_wait_child(pid_t pid, int *status, Error **errp);
>
>
> This doesn't belong here, afaict.
What do you mean, this patch or this place in the header file?
I moved this function to the global scope because it was used in
commands-posix.c
and commands-linux.c in the first version of the patchset. But now we
can leave
the function static in commands-posix.c. Should I do it?
>
> #endif
> diff --git a/qga/commands-linux.c b/qga/commands-linux.c
> new file mode 100644
> index 0000000000..214e408fcd
> --- /dev/null
> +++ b/qga/commands-linux.c
> @@ -0,0 +1,286 @@
> +/*
> + * QEMU Guest Agent Linux-specific command implementations
> + *
> + * Copyright IBM Corp. 2011
> + *
> + * Authors:
> + * Michael Roth <mdroth@linux.vnet.ibm.com>
> + * Michal Privoznik <mprivozn@redhat.com>
> + *
> + * This work is licensed under the terms of the GNU GPL, version
> 2 or later.
> + * See the COPYING file in the top-level directory.
> + */
> +
> +#include "qemu/osdep.h"
> +#include "qapi/error.h"
> +#include "commands-common.h"
> +#include "cutils.h"
> +#include <mntent.h>
> +#include <sys/ioctl.h>
> +
> +#if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM)
> +static int dev_major_minor(const char *devpath,
> + unsigned int *devmajor, unsigned int
> *devminor)
> +{
> + struct stat st;
> +
> + *devmajor = 0;
> + *devminor = 0;
> +
> + if (stat(devpath, &st) < 0) {
> + slog("failed to stat device file '%s': %s", devpath,
> strerror(errno));
> + return -1;
> + }
> + if (S_ISDIR(st.st_mode)) {
> + /* It is bind mount */
> + return -2;
> + }
> + if (S_ISBLK(st.st_mode)) {
> + *devmajor = major(st.st_rdev);
> + *devminor = minor(st.st_rdev);
> + return 0;
> + }
> + return -1;
> +}
> +
> +static bool build_fs_mount_list_from_mtab(FsMountList *mounts,
> Error **errp)
> +{
> + struct mntent *ment;
> + FsMount *mount;
> + char const *mtab = "/proc/self/mounts";
> + FILE *fp;
> + unsigned int devmajor, devminor;
> +
> + fp = setmntent(mtab, "r");
> + if (!fp) {
> + error_setg(errp, "failed to open mtab file: '%s'", mtab);
> + return false;
> + }
> +
> + while ((ment = getmntent(fp))) {
> + /*
> + * An entry which device name doesn't start with a '/' is
> + * either a dummy file system or a network file system.
> + * Add special handling for smbfs and cifs as is done by
> + * coreutils as well.
> + */
> + if ((ment->mnt_fsname[0] != '/') ||
> + (strcmp(ment->mnt_type, "smbfs") == 0) ||
> + (strcmp(ment->mnt_type, "cifs") == 0)) {
> + continue;
> + }
> + if (dev_major_minor(ment->mnt_fsname, &devmajor,
> &devminor) == -2) {
> + /* Skip bind mounts */
> + continue;
> + }
> +
> + mount = g_new0(FsMount, 1);
> + mount->dirname = g_strdup(ment->mnt_dir);
> + mount->devtype = g_strdup(ment->mnt_type);
> + mount->devmajor = devmajor;
> + mount->devminor = devminor;
> +
> + QTAILQ_INSERT_TAIL(mounts, mount, next);
> + }
> +
> + endmntent(fp);
> + return true;
> +}
> +
> +static void decode_mntname(char *name, int len)
> +{
> + int i, j = 0;
> + for (i = 0; i <= len; i++) {
> + if (name[i] != '\\') {
> + name[j++] = name[i];
> + } else if (name[i + 1] == '\\') {
> + name[j++] = '\\';
> + i++;
> + } else if (name[i + 1] >= '0' && name[i + 1] <= '3' &&
> + name[i + 2] >= '0' && name[i + 2] <= '7' &&
> + name[i + 3] >= '0' && name[i + 3] <= '7') {
> + name[j++] = (name[i + 1] - '0') * 64 +
> + (name[i + 2] - '0') * 8 +
> + (name[i + 3] - '0');
> + i += 3;
> + } else {
> + name[j++] = name[i];
> + }
> + }
> +}
> +
> +/*
> + * Walk the mount table and build a list of local file systems
> + */
> +bool build_fs_mount_list(FsMountList *mounts, Error **errp)
> +{
> + FsMount *mount;
> + char const *mountinfo = "/proc/self/mountinfo";
> + FILE *fp;
> + char *line = NULL, *dash;
> + size_t n;
> + char check;
> + unsigned int devmajor, devminor;
> + int ret, dir_s, dir_e, type_s, type_e, dev_s, dev_e;
> +
> + fp = fopen(mountinfo, "r");
> + if (!fp) {
> + return build_fs_mount_list_from_mtab(mounts, errp);
> + }
> +
> + while (getline(&line, &n, fp) != -1) {
> + ret = sscanf(line, "%*u %*u %u:%u %*s %n%*s%n%c",
> + &devmajor, &devminor, &dir_s, &dir_e, &check);
> + if (ret < 3) {
> + continue;
> + }
> + dash = strstr(line + dir_e, " - ");
> + if (!dash) {
> + continue;
> + }
> + ret = sscanf(dash, " - %n%*s%n %n%*s%n%c",
> + &type_s, &type_e, &dev_s, &dev_e, &check);
> + if (ret < 1) {
> + continue;
> + }
> + line[dir_e] = 0;
> + dash[type_e] = 0;
> + dash[dev_e] = 0;
> + decode_mntname(line + dir_s, dir_e - dir_s);
> + decode_mntname(dash + dev_s, dev_e - dev_s);
> + if (devmajor == 0) {
> + /* btrfs reports major number = 0 */
> + if (strcmp("btrfs", dash + type_s) != 0 ||
> + dev_major_minor(dash + dev_s, &devmajor,
> &devminor) < 0) {
> + continue;
> + }
> + }
> +
> + mount = g_new0(FsMount, 1);
> + mount->dirname = g_strdup(line + dir_s);
> + mount->devtype = g_strdup(dash + type_s);
> + mount->devmajor = devmajor;
> + mount->devminor = devminor;
> +
> + QTAILQ_INSERT_TAIL(mounts, mount, next);
> + }
> + free(line);
> +
> + fclose(fp);
> + return true;
> +}
> +#endif /* CONFIG_FSFREEZE || CONFIG_FSTRIM */
> +
> +#ifdef CONFIG_FSFREEZE
> +/*
> + * Walk list of mounted file systems in the guest, and freeze the
> ones which
> + * are real local file systems.
> + */
> +int64_t qmp_guest_fsfreeze_do_freeze_list(bool has_mountpoints,
> + strList *mountpoints,
> + FsMountList mounts,
> + Error **errp)
> +{
> + struct FsMount *mount;
> + strList *list;
> + int fd, ret, i = 0;
> +
> + QTAILQ_FOREACH_REVERSE(mount, &mounts, next) {
> + /* To issue fsfreeze in the reverse order of mounts,
> check if the
> + * mount is listed in the list here */
> + if (has_mountpoints) {
> + for (list = mountpoints; list; list = list->next) {
> + if (strcmp(list->value, mount->dirname) == 0) {
> + break;
> + }
> + }
> + if (!list) {
> + continue;
> + }
> + }
> +
> + fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
> + if (fd == -1) {
> + error_setg_errno(errp, errno, "failed to open %s",
> mount->dirname);
> + return -1;
> + }
> +
> + /* we try to cull filesystems we know won't work in
> advance, but other
> + * filesystems may not implement fsfreeze for less
> obvious reasons.
> + * these will report EOPNOTSUPP. we simply ignore these
> when tallying
> + * the number of frozen filesystems.
> + * if a filesystem is mounted more than once (aka bind
> mount) a
> + * consecutive attempt to freeze an already frozen
> filesystem will
> + * return EBUSY.
> + *
> + * any other error means a failure to freeze a filesystem we
> + * expect to be freezable, so return an error in those cases
> + * and return system to thawed state.
> + */
> + ret = ioctl(fd, FIFREEZE);
> + if (ret == -1) {
> + if (errno != EOPNOTSUPP && errno != EBUSY) {
> + error_setg_errno(errp, errno, "failed to freeze %s",
> + mount->dirname);
> + close(fd);
> + return -1;
> + }
> + } else {
> + i++;
> + }
> + close(fd);
> + }
> + return i;
> +}
> +
> +int qmp_guest_fsfreeze_do_thaw(Error **errp)
> +{
> + int ret;
> + FsMountList mounts;
> + FsMount *mount;
> + int fd, i = 0, logged;
> + Error *local_err = NULL;
> +
> + QTAILQ_INIT(&mounts);
> + if (!build_fs_mount_list(&mounts, &local_err)) {
> + error_propagate(errp, local_err);
> + return -1;
> + }
> +
> + QTAILQ_FOREACH(mount, &mounts, next) {
> + logged = false;
> + fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
> + if (fd == -1) {
> + continue;
> + }
> + /* we have no way of knowing whether a filesystem was
> actually unfrozen
> + * as a result of a successful call to FITHAW, only that
> if an error
> + * was returned the filesystem was *not* unfrozen by that
> particular
> + * call.
> + *
> + * since multiple preceding FIFREEZEs require multiple
> calls to FITHAW
> + * to unfreeze, continuing issuing FITHAW until an error
> is returned,
> + * in which case either the filesystem is in an
> unfreezable state, or,
> + * more likely, it was thawed previously (and remains so
> afterward).
> + *
> + * also, since the most recent successful call is the one
> that did
> + * the actual unfreeze, we can use this to provide an
> accurate count
> + * of the number of filesystems unfrozen by
> guest-fsfreeze-thaw, which
> + * may * be useful for determining whether a filesystem
> was unfrozen
> + * during the freeze/thaw phase by a process other than
> qemu-ga.
> + */
> + do {
> + ret = ioctl(fd, FITHAW);
> + if (ret == 0 && !logged) {
> + i++;
> + logged = true;
> + }
> + } while (ret == 0);
> + close(fd);
> + }
> +
> + free_fs_mount_list(&mounts);
> +
> + return i;
> +}
> +#endif /* CONFIG_FSFREEZE */
> diff --git a/qga/commands-posix.c b/qga/commands-posix.c
> index 16d67e9f6d..9574b83c92 100644
> --- a/qga/commands-posix.c
> +++ b/qga/commands-posix.c
> @@ -16,11 +16,9 @@
> #include <sys/utsname.h>
> #include <sys/wait.h>
> #include <dirent.h>
> -#include "guest-agent-core.h"
> #include "qga-qapi-commands.h"
> #include "qapi/error.h"
> #include "qapi/qmp/qerror.h"
> -#include "qemu/queue.h"
> #include "qemu/host-utils.h"
> #include "qemu/sockets.h"
> #include "qemu/base64.h"
> @@ -70,7 +68,7 @@
> #endif
> #endif
>
> -static void ga_wait_child(pid_t pid, int *status, Error **errp)
> +void ga_wait_child(pid_t pid, int *status, Error **errp)
> {
> pid_t rpid;
>
> @@ -629,16 +627,7 @@ void qmp_guest_file_flush(int64_t handle,
> Error **errp)
> #if defined(__linux__)
>
> #if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM)
> -typedef struct FsMount {
> - char *dirname;
> - char *devtype;
> - unsigned int devmajor, devminor;
> - QTAILQ_ENTRY(FsMount) next;
> -} FsMount;
> -
> -typedef QTAILQ_HEAD(FsMountList, FsMount) FsMountList;
> -
> -static void free_fs_mount_list(FsMountList *mounts)
> +void free_fs_mount_list(FsMountList *mounts)
> {
> FsMount *mount, *temp;
>
> @@ -653,157 +642,6 @@ static void free_fs_mount_list(FsMountList
> *mounts)
> g_free(mount);
> }
> }
> -
> -static int dev_major_minor(const char *devpath,
> - unsigned int *devmajor, unsigned int
> *devminor)
> -{
> - struct stat st;
> -
> - *devmajor = 0;
> - *devminor = 0;
> -
> - if (stat(devpath, &st) < 0) {
> - slog("failed to stat device file '%s': %s", devpath,
> strerror(errno));
> - return -1;
> - }
> - if (S_ISDIR(st.st_mode)) {
> - /* It is bind mount */
> - return -2;
> - }
> - if (S_ISBLK(st.st_mode)) {
> - *devmajor = major(st.st_rdev);
> - *devminor = minor(st.st_rdev);
> - return 0;
> - }
> - return -1;
> -}
> -
> -/*
> - * Walk the mount table and build a list of local file systems
> - */
> -static bool build_fs_mount_list_from_mtab(FsMountList *mounts,
> Error **errp)
> -{
> - struct mntent *ment;
> - FsMount *mount;
> - char const *mtab = "/proc/self/mounts";
> - FILE *fp;
> - unsigned int devmajor, devminor;
> -
> - fp = setmntent(mtab, "r");
> - if (!fp) {
> - error_setg(errp, "failed to open mtab file: '%s'", mtab);
> - return false;
> - }
> -
> - while ((ment = getmntent(fp))) {
> - /*
> - * An entry which device name doesn't start with a '/' is
> - * either a dummy file system or a network file system.
> - * Add special handling for smbfs and cifs as is done by
> - * coreutils as well.
> - */
> - if ((ment->mnt_fsname[0] != '/') ||
> - (strcmp(ment->mnt_type, "smbfs") == 0) ||
> - (strcmp(ment->mnt_type, "cifs") == 0)) {
> - continue;
> - }
> - if (dev_major_minor(ment->mnt_fsname, &devmajor,
> &devminor) == -2) {
> - /* Skip bind mounts */
> - continue;
> - }
> -
> - mount = g_new0(FsMount, 1);
> - mount->dirname = g_strdup(ment->mnt_dir);
> - mount->devtype = g_strdup(ment->mnt_type);
> - mount->devmajor = devmajor;
> - mount->devminor = devminor;
> -
> - QTAILQ_INSERT_TAIL(mounts, mount, next);
> - }
> -
> - endmntent(fp);
> - return true;
> -}
> -
> -static void decode_mntname(char *name, int len)
> -{
> - int i, j = 0;
> - for (i = 0; i <= len; i++) {
> - if (name[i] != '\\') {
> - name[j++] = name[i];
> - } else if (name[i + 1] == '\\') {
> - name[j++] = '\\';
> - i++;
> - } else if (name[i + 1] >= '0' && name[i + 1] <= '3' &&
> - name[i + 2] >= '0' && name[i + 2] <= '7' &&
> - name[i + 3] >= '0' && name[i + 3] <= '7') {
> - name[j++] = (name[i + 1] - '0') * 64 +
> - (name[i + 2] - '0') * 8 +
> - (name[i + 3] - '0');
> - i += 3;
> - } else {
> - name[j++] = name[i];
> - }
> - }
> -}
> -
> -static bool build_fs_mount_list(FsMountList *mounts, Error **errp)
> -{
> - FsMount *mount;
> - char const *mountinfo = "/proc/self/mountinfo";
> - FILE *fp;
> - char *line = NULL, *dash;
> - size_t n;
> - char check;
> - unsigned int devmajor, devminor;
> - int ret, dir_s, dir_e, type_s, type_e, dev_s, dev_e;
> -
> - fp = fopen(mountinfo, "r");
> - if (!fp) {
> - return build_fs_mount_list_from_mtab(mounts, errp);
> - }
> -
> - while (getline(&line, &n, fp) != -1) {
> - ret = sscanf(line, "%*u %*u %u:%u %*s %n%*s%n%c",
> - &devmajor, &devminor, &dir_s, &dir_e, &check);
> - if (ret < 3) {
> - continue;
> - }
> - dash = strstr(line + dir_e, " - ");
> - if (!dash) {
> - continue;
> - }
> - ret = sscanf(dash, " - %n%*s%n %n%*s%n%c",
> - &type_s, &type_e, &dev_s, &dev_e, &check);
> - if (ret < 1) {
> - continue;
> - }
> - line[dir_e] = 0;
> - dash[type_e] = 0;
> - dash[dev_e] = 0;
> - decode_mntname(line + dir_s, dir_e - dir_s);
> - decode_mntname(dash + dev_s, dev_e - dev_s);
> - if (devmajor == 0) {
> - /* btrfs reports major number = 0 */
> - if (strcmp("btrfs", dash + type_s) != 0 ||
> - dev_major_minor(dash + dev_s, &devmajor,
> &devminor) < 0) {
> - continue;
> - }
> - }
> -
> - mount = g_new0(FsMount, 1);
> - mount->dirname = g_strdup(line + dir_s);
> - mount->devtype = g_strdup(dash + type_s);
> - mount->devmajor = devmajor;
> - mount->devminor = devminor;
> -
> - QTAILQ_INSERT_TAIL(mounts, mount, next);
> - }
> - free(line);
> -
> - fclose(fp);
> - return true;
> -}
> #endif
>
> #if defined(CONFIG_FSFREEZE)
> @@ -1708,20 +1546,13 @@ int64_t qmp_guest_fsfreeze_freeze(Error
> **errp)
> return qmp_guest_fsfreeze_freeze_list(false, NULL, errp);
> }
>
> -/*
> - * Walk list of mounted file systems in the guest, and freeze the
> ones which
> - * are real local file systems.
> - */
> int64_t qmp_guest_fsfreeze_freeze_list(bool has_mountpoints,
> strList *mountpoints,
> Error **errp)
> {
> - int ret = 0, i = 0;
> - strList *list;
> + int ret;
> FsMountList mounts;
> - struct FsMount *mount;
> Error *local_err = NULL;
> - int fd;
>
> slog("guest-fsfreeze called");
>
> @@ -1740,122 +1571,34 @@ int64_t
> qmp_guest_fsfreeze_freeze_list(bool has_mountpoints,
> /* cannot risk guest agent blocking itself on a write in this
> state */
> ga_set_frozen(ga_state);
>
> - QTAILQ_FOREACH_REVERSE(mount, &mounts, next) {
> - /* To issue fsfreeze in the reverse order of mounts,
> check if the
> - * mount is listed in the list here */
> - if (has_mountpoints) {
> - for (list = mountpoints; list; list = list->next) {
> - if (strcmp(list->value, mount->dirname) == 0) {
> - break;
> - }
> - }
> - if (!list) {
> - continue;
> - }
> - }
> -
> - fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
> - if (fd == -1) {
> - error_setg_errno(errp, errno, "failed to open %s",
> mount->dirname);
> - goto error;
> - }
> -
> - /* we try to cull filesystems we know won't work in
> advance, but other
> - * filesystems may not implement fsfreeze for less
> obvious reasons.
> - * these will report EOPNOTSUPP. we simply ignore these
> when tallying
> - * the number of frozen filesystems.
> - * if a filesystem is mounted more than once (aka bind
> mount) a
> - * consecutive attempt to freeze an already frozen
> filesystem will
> - * return EBUSY.
> - *
> - * any other error means a failure to freeze a filesystem we
> - * expect to be freezable, so return an error in those cases
> - * and return system to thawed state.
> - */
> - ret = ioctl(fd, FIFREEZE);
> - if (ret == -1) {
> - if (errno != EOPNOTSUPP && errno != EBUSY) {
> - error_setg_errno(errp, errno, "failed to freeze %s",
> - mount->dirname);
> - close(fd);
> - goto error;
> - }
> - } else {
> - i++;
> - }
> - close(fd);
> - }
> + ret = qmp_guest_fsfreeze_do_freeze_list(has_mountpoints,
> mountpoints,
> + mounts, errp);
>
> free_fs_mount_list(&mounts);
> /* We may not issue any FIFREEZE here.
> * Just unset ga_state here and ready for the next call.
> */
> - if (i == 0) {
> + if (ret == 0) {
> ga_unset_frozen(ga_state);
> + } else if (ret < 0) {
> + qmp_guest_fsfreeze_thaw(NULL);
> }
> - return i;
> -
> -error:
> - free_fs_mount_list(&mounts);
> - qmp_guest_fsfreeze_thaw(NULL);
> - return 0;
> + return ret;
> }
>
> -/*
> - * Walk list of frozen file systems in the guest, and thaw them.
> - */
> int64_t qmp_guest_fsfreeze_thaw(Error **errp)
> {
> int ret;
> - FsMountList mounts;
> - FsMount *mount;
> - int fd, i = 0, logged;
> - Error *local_err = NULL;
>
> - QTAILQ_INIT(&mounts);
> - if (!build_fs_mount_list(&mounts, &local_err)) {
> - error_propagate(errp, local_err);
> - return 0;
> + ret = qmp_guest_fsfreeze_do_thaw(errp);
> + if (ret >= 0) {
> + ga_unset_frozen(ga_state);
> + execute_fsfreeze_hook(FSFREEZE_HOOK_THAW, errp);
> + } else {
> + ret = 0;
> }
>
> - QTAILQ_FOREACH(mount, &mounts, next) {
> - logged = false;
> - fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
> - if (fd == -1) {
> - continue;
> - }
> - /* we have no way of knowing whether a filesystem was
> actually unfrozen
> - * as a result of a successful call to FITHAW, only that
> if an error
> - * was returned the filesystem was *not* unfrozen by that
> particular
> - * call.
> - *
> - * since multiple preceding FIFREEZEs require multiple
> calls to FITHAW
> - * to unfreeze, continuing issuing FITHAW until an error
> is returned,
> - * in which case either the filesystem is in an
> unfreezable state, or,
> - * more likely, it was thawed previously (and remains so
> afterward).
> - *
> - * also, since the most recent successful call is the one
> that did
> - * the actual unfreeze, we can use this to provide an
> accurate count
> - * of the number of filesystems unfrozen by
> guest-fsfreeze-thaw, which
> - * may * be useful for determining whether a filesystem
> was unfrozen
> - * during the freeze/thaw phase by a process other than
> qemu-ga.
> - */
> - do {
> - ret = ioctl(fd, FITHAW);
> - if (ret == 0 && !logged) {
> - i++;
> - logged = true;
> - }
> - } while (ret == 0);
> - close(fd);
> - }
> -
> - ga_unset_frozen(ga_state);
> - free_fs_mount_list(&mounts);
> -
> - execute_fsfreeze_hook(FSFREEZE_HOOK_THAW, errp);
> -
> - return i;
> + return ret;
> }
>
> static void guest_fsfreeze_cleanup(void)
> diff --git a/qga/meson.build b/qga/meson.build
> index a0ffd6d268..932b4e7ca8 100644
> --- a/qga/meson.build
> +++ b/qga/meson.build
> @@ -72,6 +72,9 @@ qga_ss.add(when: 'CONFIG_POSIX', if_true: files(
> 'commands-posix.c',
> 'commands-posix-ssh.c',
> ))
> +qga_ss.add(when: 'CONFIG_LINUX', if_true: files(
> + 'commands-linux.c',
> +))
> qga_ss.add(when: 'CONFIG_WIN32', if_true: files(
> 'channel-win32.c',
> 'commands-win32.c',
> --
> 2.34.1
>
>
>
> --
> Marc-André Lureau
Hi
On Fri, Oct 14, 2022 at 11:56 AM Alexander Ivanov <
alexander.ivanov@virtuozzo.com> wrote:
> Hi
> On 13.10.2022 14:10, Marc-André Lureau wrote:
>
> Hi
>
> On Thu, Oct 13, 2022 at 1:23 PM Alexander Ivanov <
> alexander.ivanov@virtuozzo.com> wrote:
>
>> In the next patches we are going to add FreeBSD support for QEMU Guest
>> Agent. In the result, code in commands-posix.c will be too cumbersome.
>>
>> Move Linux-specific FS freeze/thaw code to a separate file
>> commands-linux.c
>> keeping common POSIX code in commands-posix.c.
>>
>> Reviewed-by: Konstantin Kostiuk <kkostiuk@redhat.com>
>> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
>> Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
>> ---
>> qga/commands-common.h | 35 +++++
>> qga/commands-linux.c | 286 +++++++++++++++++++++++++++++++++++++++++
>> qga/commands-posix.c | 289 +++---------------------------------------
>> qga/meson.build | 3 +
>> 4 files changed, 340 insertions(+), 273 deletions(-)
>> create mode 100644 qga/commands-linux.c
>>
>> diff --git a/qga/commands-common.h b/qga/commands-common.h
>> index d0e4a9696f..181fc330aa 100644
>> --- a/qga/commands-common.h
>> +++ b/qga/commands-common.h
>> @@ -10,6 +10,40 @@
>> #define QGA_COMMANDS_COMMON_H
>>
>> #include "qga-qapi-types.h"
>> +#include "guest-agent-core.h"
>> +#include "qemu/queue.h"
>> +
>> +#if defined(__linux__)
>> +#include <linux/fs.h>
>> +#ifdef FIFREEZE
>> +#define CONFIG_FSFREEZE
>> +#endif
>> +#ifdef FITRIM
>> +#define CONFIG_FSTRIM
>> +#endif
>> +#endif /* __linux__ */
>> +
>> +#if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM)
>> +typedef struct FsMount {
>> + char *dirname;
>> + char *devtype;
>> + unsigned int devmajor, devminor;
>> + QTAILQ_ENTRY(FsMount) next;
>> +} FsMount;
>> +
>> +typedef QTAILQ_HEAD(FsMountList, FsMount) FsMountList;
>> +
>> +bool build_fs_mount_list(FsMountList *mounts, Error **errp);
>> +void free_fs_mount_list(FsMountList *mounts);
>> +#endif /* CONFIG_FSFREEZE || CONFIG_FSTRIM */
>> +
>> +#if defined(CONFIG_FSFREEZE)
>> +int64_t qmp_guest_fsfreeze_do_freeze_list(bool has_mountpoints,
>> + strList *mountpoints,
>> + FsMountList mounts,
>> + Error **errp);
>> +int qmp_guest_fsfreeze_do_thaw(Error **errp);
>> +#endif /* CONFIG_FSFREEZE */
>>
>> typedef struct GuestFileHandle GuestFileHandle;
>>
>> @@ -29,4 +63,5 @@ GuestFileRead *guest_file_read_unsafe(GuestFileHandle
>> *gfh,
>> */
>> char *qga_get_host_name(Error **errp);
>>
>> +void ga_wait_child(pid_t pid, int *status, Error **errp);
>>
>
> This doesn't belong here, afaict.
>
> What do you mean, this patch or this place in the header file?
>
I mean that this change doesn't look necessary with this patch.
> I moved this function to the global scope because it was used in
> commands-posix.c
>
> and commands-linux.c in the first version of the patchset. But now we can
> leave
>
> the function static in commands-posix.c. Should I do it?
>
yes, don't change it if not needed, thanks !
>
>
>
>> #endif
>> diff --git a/qga/commands-linux.c b/qga/commands-linux.c
>> new file mode 100644
>> index 0000000000..214e408fcd
>> --- /dev/null
>> +++ b/qga/commands-linux.c
>> @@ -0,0 +1,286 @@
>> +/*
>> + * QEMU Guest Agent Linux-specific command implementations
>> + *
>> + * Copyright IBM Corp. 2011
>> + *
>> + * Authors:
>> + * Michael Roth <mdroth@linux.vnet.ibm.com>
>> + * Michal Privoznik <mprivozn@redhat.com>
>> + *
>> + * This work is licensed under the terms of the GNU GPL, version 2 or
>> later.
>> + * See the COPYING file in the top-level directory.
>> + */
>> +
>> +#include "qemu/osdep.h"
>> +#include "qapi/error.h"
>> +#include "commands-common.h"
>> +#include "cutils.h"
>> +#include <mntent.h>
>> +#include <sys/ioctl.h>
>> +
>> +#if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM)
>> +static int dev_major_minor(const char *devpath,
>> + unsigned int *devmajor, unsigned int
>> *devminor)
>> +{
>> + struct stat st;
>> +
>> + *devmajor = 0;
>> + *devminor = 0;
>> +
>> + if (stat(devpath, &st) < 0) {
>> + slog("failed to stat device file '%s': %s", devpath,
>> strerror(errno));
>> + return -1;
>> + }
>> + if (S_ISDIR(st.st_mode)) {
>> + /* It is bind mount */
>> + return -2;
>> + }
>> + if (S_ISBLK(st.st_mode)) {
>> + *devmajor = major(st.st_rdev);
>> + *devminor = minor(st.st_rdev);
>> + return 0;
>> + }
>> + return -1;
>> +}
>> +
>> +static bool build_fs_mount_list_from_mtab(FsMountList *mounts, Error
>> **errp)
>> +{
>> + struct mntent *ment;
>> + FsMount *mount;
>> + char const *mtab = "/proc/self/mounts";
>> + FILE *fp;
>> + unsigned int devmajor, devminor;
>> +
>> + fp = setmntent(mtab, "r");
>> + if (!fp) {
>> + error_setg(errp, "failed to open mtab file: '%s'", mtab);
>> + return false;
>> + }
>> +
>> + while ((ment = getmntent(fp))) {
>> + /*
>> + * An entry which device name doesn't start with a '/' is
>> + * either a dummy file system or a network file system.
>> + * Add special handling for smbfs and cifs as is done by
>> + * coreutils as well.
>> + */
>> + if ((ment->mnt_fsname[0] != '/') ||
>> + (strcmp(ment->mnt_type, "smbfs") == 0) ||
>> + (strcmp(ment->mnt_type, "cifs") == 0)) {
>> + continue;
>> + }
>> + if (dev_major_minor(ment->mnt_fsname, &devmajor, &devminor) ==
>> -2) {
>> + /* Skip bind mounts */
>> + continue;
>> + }
>> +
>> + mount = g_new0(FsMount, 1);
>> + mount->dirname = g_strdup(ment->mnt_dir);
>> + mount->devtype = g_strdup(ment->mnt_type);
>> + mount->devmajor = devmajor;
>> + mount->devminor = devminor;
>> +
>> + QTAILQ_INSERT_TAIL(mounts, mount, next);
>> + }
>> +
>> + endmntent(fp);
>> + return true;
>> +}
>> +
>> +static void decode_mntname(char *name, int len)
>> +{
>> + int i, j = 0;
>> + for (i = 0; i <= len; i++) {
>> + if (name[i] != '\\') {
>> + name[j++] = name[i];
>> + } else if (name[i + 1] == '\\') {
>> + name[j++] = '\\';
>> + i++;
>> + } else if (name[i + 1] >= '0' && name[i + 1] <= '3' &&
>> + name[i + 2] >= '0' && name[i + 2] <= '7' &&
>> + name[i + 3] >= '0' && name[i + 3] <= '7') {
>> + name[j++] = (name[i + 1] - '0') * 64 +
>> + (name[i + 2] - '0') * 8 +
>> + (name[i + 3] - '0');
>> + i += 3;
>> + } else {
>> + name[j++] = name[i];
>> + }
>> + }
>> +}
>> +
>> +/*
>> + * Walk the mount table and build a list of local file systems
>> + */
>> +bool build_fs_mount_list(FsMountList *mounts, Error **errp)
>> +{
>> + FsMount *mount;
>> + char const *mountinfo = "/proc/self/mountinfo";
>> + FILE *fp;
>> + char *line = NULL, *dash;
>> + size_t n;
>> + char check;
>> + unsigned int devmajor, devminor;
>> + int ret, dir_s, dir_e, type_s, type_e, dev_s, dev_e;
>> +
>> + fp = fopen(mountinfo, "r");
>> + if (!fp) {
>> + return build_fs_mount_list_from_mtab(mounts, errp);
>> + }
>> +
>> + while (getline(&line, &n, fp) != -1) {
>> + ret = sscanf(line, "%*u %*u %u:%u %*s %n%*s%n%c",
>> + &devmajor, &devminor, &dir_s, &dir_e, &check);
>> + if (ret < 3) {
>> + continue;
>> + }
>> + dash = strstr(line + dir_e, " - ");
>> + if (!dash) {
>> + continue;
>> + }
>> + ret = sscanf(dash, " - %n%*s%n %n%*s%n%c",
>> + &type_s, &type_e, &dev_s, &dev_e, &check);
>> + if (ret < 1) {
>> + continue;
>> + }
>> + line[dir_e] = 0;
>> + dash[type_e] = 0;
>> + dash[dev_e] = 0;
>> + decode_mntname(line + dir_s, dir_e - dir_s);
>> + decode_mntname(dash + dev_s, dev_e - dev_s);
>> + if (devmajor == 0) {
>> + /* btrfs reports major number = 0 */
>> + if (strcmp("btrfs", dash + type_s) != 0 ||
>> + dev_major_minor(dash + dev_s, &devmajor, &devminor) < 0)
>> {
>> + continue;
>> + }
>> + }
>> +
>> + mount = g_new0(FsMount, 1);
>> + mount->dirname = g_strdup(line + dir_s);
>> + mount->devtype = g_strdup(dash + type_s);
>> + mount->devmajor = devmajor;
>> + mount->devminor = devminor;
>> +
>> + QTAILQ_INSERT_TAIL(mounts, mount, next);
>> + }
>> + free(line);
>> +
>> + fclose(fp);
>> + return true;
>> +}
>> +#endif /* CONFIG_FSFREEZE || CONFIG_FSTRIM */
>> +
>> +#ifdef CONFIG_FSFREEZE
>> +/*
>> + * Walk list of mounted file systems in the guest, and freeze the ones
>> which
>> + * are real local file systems.
>> + */
>> +int64_t qmp_guest_fsfreeze_do_freeze_list(bool has_mountpoints,
>> + strList *mountpoints,
>> + FsMountList mounts,
>> + Error **errp)
>> +{
>> + struct FsMount *mount;
>> + strList *list;
>> + int fd, ret, i = 0;
>> +
>> + QTAILQ_FOREACH_REVERSE(mount, &mounts, next) {
>> + /* To issue fsfreeze in the reverse order of mounts, check if the
>> + * mount is listed in the list here */
>> + if (has_mountpoints) {
>> + for (list = mountpoints; list; list = list->next) {
>> + if (strcmp(list->value, mount->dirname) == 0) {
>> + break;
>> + }
>> + }
>> + if (!list) {
>> + continue;
>> + }
>> + }
>> +
>> + fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
>> + if (fd == -1) {
>> + error_setg_errno(errp, errno, "failed to open %s",
>> mount->dirname);
>> + return -1;
>> + }
>> +
>> + /* we try to cull filesystems we know won't work in advance, but
>> other
>> + * filesystems may not implement fsfreeze for less obvious
>> reasons.
>> + * these will report EOPNOTSUPP. we simply ignore these when
>> tallying
>> + * the number of frozen filesystems.
>> + * if a filesystem is mounted more than once (aka bind mount) a
>> + * consecutive attempt to freeze an already frozen filesystem
>> will
>> + * return EBUSY.
>> + *
>> + * any other error means a failure to freeze a filesystem we
>> + * expect to be freezable, so return an error in those cases
>> + * and return system to thawed state.
>> + */
>> + ret = ioctl(fd, FIFREEZE);
>> + if (ret == -1) {
>> + if (errno != EOPNOTSUPP && errno != EBUSY) {
>> + error_setg_errno(errp, errno, "failed to freeze %s",
>> + mount->dirname);
>> + close(fd);
>> + return -1;
>> + }
>> + } else {
>> + i++;
>> + }
>> + close(fd);
>> + }
>> + return i;
>> +}
>> +
>> +int qmp_guest_fsfreeze_do_thaw(Error **errp)
>> +{
>> + int ret;
>> + FsMountList mounts;
>> + FsMount *mount;
>> + int fd, i = 0, logged;
>> + Error *local_err = NULL;
>> +
>> + QTAILQ_INIT(&mounts);
>> + if (!build_fs_mount_list(&mounts, &local_err)) {
>> + error_propagate(errp, local_err);
>> + return -1;
>> + }
>> +
>> + QTAILQ_FOREACH(mount, &mounts, next) {
>> + logged = false;
>> + fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
>> + if (fd == -1) {
>> + continue;
>> + }
>> + /* we have no way of knowing whether a filesystem was actually
>> unfrozen
>> + * as a result of a successful call to FITHAW, only that if an
>> error
>> + * was returned the filesystem was *not* unfrozen by that
>> particular
>> + * call.
>> + *
>> + * since multiple preceding FIFREEZEs require multiple calls to
>> FITHAW
>> + * to unfreeze, continuing issuing FITHAW until an error is
>> returned,
>> + * in which case either the filesystem is in an unfreezable
>> state, or,
>> + * more likely, it was thawed previously (and remains so
>> afterward).
>> + *
>> + * also, since the most recent successful call is the one that
>> did
>> + * the actual unfreeze, we can use this to provide an accurate
>> count
>> + * of the number of filesystems unfrozen by guest-fsfreeze-thaw,
>> which
>> + * may * be useful for determining whether a filesystem was
>> unfrozen
>> + * during the freeze/thaw phase by a process other than qemu-ga.
>> + */
>> + do {
>> + ret = ioctl(fd, FITHAW);
>> + if (ret == 0 && !logged) {
>> + i++;
>> + logged = true;
>> + }
>> + } while (ret == 0);
>> + close(fd);
>> + }
>> +
>> + free_fs_mount_list(&mounts);
>> +
>> + return i;
>> +}
>> +#endif /* CONFIG_FSFREEZE */
>> diff --git a/qga/commands-posix.c b/qga/commands-posix.c
>> index 16d67e9f6d..9574b83c92 100644
>> --- a/qga/commands-posix.c
>> +++ b/qga/commands-posix.c
>> @@ -16,11 +16,9 @@
>> #include <sys/utsname.h>
>> #include <sys/wait.h>
>> #include <dirent.h>
>> -#include "guest-agent-core.h"
>> #include "qga-qapi-commands.h"
>> #include "qapi/error.h"
>> #include "qapi/qmp/qerror.h"
>> -#include "qemu/queue.h"
>> #include "qemu/host-utils.h"
>> #include "qemu/sockets.h"
>> #include "qemu/base64.h"
>> @@ -70,7 +68,7 @@
>> #endif
>> #endif
>>
>> -static void ga_wait_child(pid_t pid, int *status, Error **errp)
>> +void ga_wait_child(pid_t pid, int *status, Error **errp)
>> {
>> pid_t rpid;
>>
>> @@ -629,16 +627,7 @@ void qmp_guest_file_flush(int64_t handle, Error
>> **errp)
>> #if defined(__linux__)
>>
>> #if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM)
>> -typedef struct FsMount {
>> - char *dirname;
>> - char *devtype;
>> - unsigned int devmajor, devminor;
>> - QTAILQ_ENTRY(FsMount) next;
>> -} FsMount;
>> -
>> -typedef QTAILQ_HEAD(FsMountList, FsMount) FsMountList;
>> -
>> -static void free_fs_mount_list(FsMountList *mounts)
>> +void free_fs_mount_list(FsMountList *mounts)
>> {
>> FsMount *mount, *temp;
>>
>> @@ -653,157 +642,6 @@ static void free_fs_mount_list(FsMountList *mounts)
>> g_free(mount);
>> }
>> }
>> -
>> -static int dev_major_minor(const char *devpath,
>> - unsigned int *devmajor, unsigned int
>> *devminor)
>> -{
>> - struct stat st;
>> -
>> - *devmajor = 0;
>> - *devminor = 0;
>> -
>> - if (stat(devpath, &st) < 0) {
>> - slog("failed to stat device file '%s': %s", devpath,
>> strerror(errno));
>> - return -1;
>> - }
>> - if (S_ISDIR(st.st_mode)) {
>> - /* It is bind mount */
>> - return -2;
>> - }
>> - if (S_ISBLK(st.st_mode)) {
>> - *devmajor = major(st.st_rdev);
>> - *devminor = minor(st.st_rdev);
>> - return 0;
>> - }
>> - return -1;
>> -}
>> -
>> -/*
>> - * Walk the mount table and build a list of local file systems
>> - */
>> -static bool build_fs_mount_list_from_mtab(FsMountList *mounts, Error
>> **errp)
>> -{
>> - struct mntent *ment;
>> - FsMount *mount;
>> - char const *mtab = "/proc/self/mounts";
>> - FILE *fp;
>> - unsigned int devmajor, devminor;
>> -
>> - fp = setmntent(mtab, "r");
>> - if (!fp) {
>> - error_setg(errp, "failed to open mtab file: '%s'", mtab);
>> - return false;
>> - }
>> -
>> - while ((ment = getmntent(fp))) {
>> - /*
>> - * An entry which device name doesn't start with a '/' is
>> - * either a dummy file system or a network file system.
>> - * Add special handling for smbfs and cifs as is done by
>> - * coreutils as well.
>> - */
>> - if ((ment->mnt_fsname[0] != '/') ||
>> - (strcmp(ment->mnt_type, "smbfs") == 0) ||
>> - (strcmp(ment->mnt_type, "cifs") == 0)) {
>> - continue;
>> - }
>> - if (dev_major_minor(ment->mnt_fsname, &devmajor, &devminor) ==
>> -2) {
>> - /* Skip bind mounts */
>> - continue;
>> - }
>> -
>> - mount = g_new0(FsMount, 1);
>> - mount->dirname = g_strdup(ment->mnt_dir);
>> - mount->devtype = g_strdup(ment->mnt_type);
>> - mount->devmajor = devmajor;
>> - mount->devminor = devminor;
>> -
>> - QTAILQ_INSERT_TAIL(mounts, mount, next);
>> - }
>> -
>> - endmntent(fp);
>> - return true;
>> -}
>> -
>> -static void decode_mntname(char *name, int len)
>> -{
>> - int i, j = 0;
>> - for (i = 0; i <= len; i++) {
>> - if (name[i] != '\\') {
>> - name[j++] = name[i];
>> - } else if (name[i + 1] == '\\') {
>> - name[j++] = '\\';
>> - i++;
>> - } else if (name[i + 1] >= '0' && name[i + 1] <= '3' &&
>> - name[i + 2] >= '0' && name[i + 2] <= '7' &&
>> - name[i + 3] >= '0' && name[i + 3] <= '7') {
>> - name[j++] = (name[i + 1] - '0') * 64 +
>> - (name[i + 2] - '0') * 8 +
>> - (name[i + 3] - '0');
>> - i += 3;
>> - } else {
>> - name[j++] = name[i];
>> - }
>> - }
>> -}
>> -
>> -static bool build_fs_mount_list(FsMountList *mounts, Error **errp)
>> -{
>> - FsMount *mount;
>> - char const *mountinfo = "/proc/self/mountinfo";
>> - FILE *fp;
>> - char *line = NULL, *dash;
>> - size_t n;
>> - char check;
>> - unsigned int devmajor, devminor;
>> - int ret, dir_s, dir_e, type_s, type_e, dev_s, dev_e;
>> -
>> - fp = fopen(mountinfo, "r");
>> - if (!fp) {
>> - return build_fs_mount_list_from_mtab(mounts, errp);
>> - }
>> -
>> - while (getline(&line, &n, fp) != -1) {
>> - ret = sscanf(line, "%*u %*u %u:%u %*s %n%*s%n%c",
>> - &devmajor, &devminor, &dir_s, &dir_e, &check);
>> - if (ret < 3) {
>> - continue;
>> - }
>> - dash = strstr(line + dir_e, " - ");
>> - if (!dash) {
>> - continue;
>> - }
>> - ret = sscanf(dash, " - %n%*s%n %n%*s%n%c",
>> - &type_s, &type_e, &dev_s, &dev_e, &check);
>> - if (ret < 1) {
>> - continue;
>> - }
>> - line[dir_e] = 0;
>> - dash[type_e] = 0;
>> - dash[dev_e] = 0;
>> - decode_mntname(line + dir_s, dir_e - dir_s);
>> - decode_mntname(dash + dev_s, dev_e - dev_s);
>> - if (devmajor == 0) {
>> - /* btrfs reports major number = 0 */
>> - if (strcmp("btrfs", dash + type_s) != 0 ||
>> - dev_major_minor(dash + dev_s, &devmajor, &devminor) < 0)
>> {
>> - continue;
>> - }
>> - }
>> -
>> - mount = g_new0(FsMount, 1);
>> - mount->dirname = g_strdup(line + dir_s);
>> - mount->devtype = g_strdup(dash + type_s);
>> - mount->devmajor = devmajor;
>> - mount->devminor = devminor;
>> -
>> - QTAILQ_INSERT_TAIL(mounts, mount, next);
>> - }
>> - free(line);
>> -
>> - fclose(fp);
>> - return true;
>> -}
>> #endif
>>
>> #if defined(CONFIG_FSFREEZE)
>> @@ -1708,20 +1546,13 @@ int64_t qmp_guest_fsfreeze_freeze(Error **errp)
>> return qmp_guest_fsfreeze_freeze_list(false, NULL, errp);
>> }
>>
>> -/*
>> - * Walk list of mounted file systems in the guest, and freeze the ones
>> which
>> - * are real local file systems.
>> - */
>> int64_t qmp_guest_fsfreeze_freeze_list(bool has_mountpoints,
>> strList *mountpoints,
>> Error **errp)
>> {
>> - int ret = 0, i = 0;
>> - strList *list;
>> + int ret;
>> FsMountList mounts;
>> - struct FsMount *mount;
>> Error *local_err = NULL;
>> - int fd;
>>
>> slog("guest-fsfreeze called");
>>
>> @@ -1740,122 +1571,34 @@ int64_t qmp_guest_fsfreeze_freeze_list(bool
>> has_mountpoints,
>> /* cannot risk guest agent blocking itself on a write in this state
>> */
>> ga_set_frozen(ga_state);
>>
>> - QTAILQ_FOREACH_REVERSE(mount, &mounts, next) {
>> - /* To issue fsfreeze in the reverse order of mounts, check if the
>> - * mount is listed in the list here */
>> - if (has_mountpoints) {
>> - for (list = mountpoints; list; list = list->next) {
>> - if (strcmp(list->value, mount->dirname) == 0) {
>> - break;
>> - }
>> - }
>> - if (!list) {
>> - continue;
>> - }
>> - }
>> -
>> - fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
>> - if (fd == -1) {
>> - error_setg_errno(errp, errno, "failed to open %s",
>> mount->dirname);
>> - goto error;
>> - }
>> -
>> - /* we try to cull filesystems we know won't work in advance, but
>> other
>> - * filesystems may not implement fsfreeze for less obvious
>> reasons.
>> - * these will report EOPNOTSUPP. we simply ignore these when
>> tallying
>> - * the number of frozen filesystems.
>> - * if a filesystem is mounted more than once (aka bind mount) a
>> - * consecutive attempt to freeze an already frozen filesystem
>> will
>> - * return EBUSY.
>> - *
>> - * any other error means a failure to freeze a filesystem we
>> - * expect to be freezable, so return an error in those cases
>> - * and return system to thawed state.
>> - */
>> - ret = ioctl(fd, FIFREEZE);
>> - if (ret == -1) {
>> - if (errno != EOPNOTSUPP && errno != EBUSY) {
>> - error_setg_errno(errp, errno, "failed to freeze %s",
>> - mount->dirname);
>> - close(fd);
>> - goto error;
>> - }
>> - } else {
>> - i++;
>> - }
>> - close(fd);
>> - }
>> + ret = qmp_guest_fsfreeze_do_freeze_list(has_mountpoints, mountpoints,
>> + mounts, errp);
>>
>> free_fs_mount_list(&mounts);
>> /* We may not issue any FIFREEZE here.
>> * Just unset ga_state here and ready for the next call.
>> */
>> - if (i == 0) {
>> + if (ret == 0) {
>> ga_unset_frozen(ga_state);
>> + } else if (ret < 0) {
>> + qmp_guest_fsfreeze_thaw(NULL);
>> }
>> - return i;
>> -
>> -error:
>> - free_fs_mount_list(&mounts);
>> - qmp_guest_fsfreeze_thaw(NULL);
>> - return 0;
>> + return ret;
>> }
>>
>> -/*
>> - * Walk list of frozen file systems in the guest, and thaw them.
>> - */
>> int64_t qmp_guest_fsfreeze_thaw(Error **errp)
>> {
>> int ret;
>> - FsMountList mounts;
>> - FsMount *mount;
>> - int fd, i = 0, logged;
>> - Error *local_err = NULL;
>>
>> - QTAILQ_INIT(&mounts);
>> - if (!build_fs_mount_list(&mounts, &local_err)) {
>> - error_propagate(errp, local_err);
>> - return 0;
>> + ret = qmp_guest_fsfreeze_do_thaw(errp);
>> + if (ret >= 0) {
>> + ga_unset_frozen(ga_state);
>> + execute_fsfreeze_hook(FSFREEZE_HOOK_THAW, errp);
>> + } else {
>> + ret = 0;
>> }
>>
>> - QTAILQ_FOREACH(mount, &mounts, next) {
>> - logged = false;
>> - fd = qga_open_cloexec(mount->dirname, O_RDONLY, 0);
>> - if (fd == -1) {
>> - continue;
>> - }
>> - /* we have no way of knowing whether a filesystem was actually
>> unfrozen
>> - * as a result of a successful call to FITHAW, only that if an
>> error
>> - * was returned the filesystem was *not* unfrozen by that
>> particular
>> - * call.
>> - *
>> - * since multiple preceding FIFREEZEs require multiple calls to
>> FITHAW
>> - * to unfreeze, continuing issuing FITHAW until an error is
>> returned,
>> - * in which case either the filesystem is in an unfreezable
>> state, or,
>> - * more likely, it was thawed previously (and remains so
>> afterward).
>> - *
>> - * also, since the most recent successful call is the one that
>> did
>> - * the actual unfreeze, we can use this to provide an accurate
>> count
>> - * of the number of filesystems unfrozen by guest-fsfreeze-thaw,
>> which
>> - * may * be useful for determining whether a filesystem was
>> unfrozen
>> - * during the freeze/thaw phase by a process other than qemu-ga.
>> - */
>> - do {
>> - ret = ioctl(fd, FITHAW);
>> - if (ret == 0 && !logged) {
>> - i++;
>> - logged = true;
>> - }
>> - } while (ret == 0);
>> - close(fd);
>> - }
>> -
>> - ga_unset_frozen(ga_state);
>> - free_fs_mount_list(&mounts);
>> -
>> - execute_fsfreeze_hook(FSFREEZE_HOOK_THAW, errp);
>> -
>> - return i;
>> + return ret;
>> }
>>
>> static void guest_fsfreeze_cleanup(void)
>> diff --git a/qga/meson.build b/qga/meson.build
>> index a0ffd6d268..932b4e7ca8 100644
>> --- a/qga/meson.build
>> +++ b/qga/meson.build
>> @@ -72,6 +72,9 @@ qga_ss.add(when: 'CONFIG_POSIX', if_true: files(
>> 'commands-posix.c',
>> 'commands-posix-ssh.c',
>> ))
>> +qga_ss.add(when: 'CONFIG_LINUX', if_true: files(
>> + 'commands-linux.c',
>> +))
>> qga_ss.add(when: 'CONFIG_WIN32', if_true: files(
>> 'channel-win32.c',
>> 'commands-win32.c',
>> --
>> 2.34.1
>>
>>
>
> --
> Marc-André Lureau
>
>
--
Marc-André Lureau
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