From bad0001eeb34484c4595c3862e14a4ee22a3abee Mon Sep 17 00:00:00 2001 From: Alexander Ivanov Date: Mon, 17 Oct 2022 09:28:21 +0200 Subject: [PATCH] qga: Add UFS freeze/thaw support for FreeBSD MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit UFS supports FS freezing through ioctl UFSSUSPEND on /dev/ufssuspend. Frozen FS can be thawed by closing /dev/ufssuspend file descriptior. Use getmntinfo to get a list of mounted FS. Reviewed-by: Konstantin Kostiuk Reviewed-by: Marc-André Lureau Signed-off-by: Alexander Ivanov Signed-off-by: Konstantin Kostiuk --- qga/commands-bsd.c | 169 +++++++++++++++++++++++ qga/commands-common.h | 11 ++ qga/commands-posix.c | 308 ++++++++++++++++++++---------------------- qga/main.c | 7 +- qga/meson.build | 3 + 5 files changed, 334 insertions(+), 164 deletions(-) create mode 100644 qga/commands-bsd.c diff --git a/qga/commands-bsd.c b/qga/commands-bsd.c new file mode 100644 index 0000000000..ca06692179 --- /dev/null +++ b/qga/commands-bsd.c @@ -0,0 +1,169 @@ +/* + * QEMU Guest Agent BSD-specific command implementations + * + * Copyright (c) Virtuozzo International GmbH. + * + * Authors: + * Alexander Ivanov + * + * 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 "qga-qapi-commands.h" +#include "qapi/qmp/qerror.h" +#include "qapi/error.h" +#include "qemu/queue.h" +#include "commands-common.h" +#include +#include +#include +#include +#include + +#if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM) +bool build_fs_mount_list(FsMountList *mounts, Error **errp) +{ + FsMount *mount; + struct statfs *mntbuf, *mntp; + struct stat statbuf; + int i, count, ret; + + count = getmntinfo(&mntbuf, MNT_NOWAIT); + if (count == 0) { + error_setg_errno(errp, errno, "getmntinfo failed"); + return false; + } + + for (i = 0; i < count; i++) { + mntp = &mntbuf[i]; + ret = stat(mntp->f_mntonname, &statbuf); + if (ret != 0) { + error_setg_errno(errp, errno, "stat failed on %s", + mntp->f_mntonname); + return false; + } + + mount = g_new0(FsMount, 1); + + mount->dirname = g_strdup(mntp->f_mntonname); + mount->devtype = g_strdup(mntp->f_fstypename); + mount->devmajor = major(mount->dev); + mount->devminor = minor(mount->dev); + mount->fsid = mntp->f_fsid; + mount->dev = statbuf.st_dev; + + QTAILQ_INSERT_TAIL(mounts, mount, next); + } + return true; +} +#endif /* CONFIG_FSFREEZE || CONFIG_FSTRIM */ + +#if defined(CONFIG_FSFREEZE) +static int ufssuspend_fd = -1; +static int ufssuspend_cnt; + +int64_t qmp_guest_fsfreeze_do_freeze_list(bool has_mountpoints, + strList *mountpoints, + FsMountList mounts, + Error **errp) +{ + int ret; + strList *list; + struct FsMount *mount; + + if (ufssuspend_fd != -1) { + error_setg(errp, "filesystems have already frozen"); + return -1; + } + + ufssuspend_cnt = 0; + ufssuspend_fd = qemu_open(_PATH_UFSSUSPEND, O_RDWR, errp); + if (ufssuspend_fd == -1) { + return -1; + } + + 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 (g_str_equal(list->value, mount->dirname)) { + break; + } + } + if (!list) { + continue; + } + } + + /* Only UFS supports suspend */ + if (!g_str_equal(mount->devtype, "ufs")) { + continue; + } + + ret = ioctl(ufssuspend_fd, UFSSUSPEND, &mount->fsid); + if (ret == -1) { + /* + * ioctl returns EBUSY for all the FS except the first one + * that was suspended + */ + if (errno == EBUSY) { + continue; + } + error_setg_errno(errp, errno, "failed to freeze %s", + mount->dirname); + goto error; + } + ufssuspend_cnt++; + } + return ufssuspend_cnt; +error: + close(ufssuspend_fd); + ufssuspend_fd = -1; + return -1; + +} + +/* + * We don't need to call UFSRESUME ioctl because all the frozen FS + * are thawed on /dev/ufssuspend closing. + */ +int qmp_guest_fsfreeze_do_thaw(Error **errp) +{ + int ret = ufssuspend_cnt; + ufssuspend_cnt = 0; + if (ufssuspend_fd != -1) { + close(ufssuspend_fd); + ufssuspend_fd = -1; + } + return ret; +} + +GuestFilesystemInfoList *qmp_guest_get_fsinfo(Error **errp) +{ + error_setg(errp, QERR_UNSUPPORTED); + return NULL; +} + +GuestDiskInfoList *qmp_guest_get_disks(Error **errp) +{ + error_setg(errp, QERR_UNSUPPORTED); + return NULL; +} + +GuestDiskStatsInfoList *qmp_guest_get_diskstats(Error **errp) +{ + error_setg(errp, QERR_UNSUPPORTED); + return NULL; +} + +GuestCpuStatsList *qmp_guest_get_cpustats(Error **errp) +{ + error_setg(errp, QERR_UNSUPPORTED); + return NULL; +} +#endif /* CONFIG_FSFREEZE */ diff --git a/qga/commands-common.h b/qga/commands-common.h index cb51b1c6e9..d0583c6ddb 100644 --- a/qga/commands-common.h +++ b/qga/commands-common.h @@ -23,11 +23,22 @@ #endif #endif /* __linux__ */ +#ifdef __FreeBSD__ +#include +#ifdef UFSSUSPEND +#define CONFIG_FSFREEZE +#endif +#endif /* __FreeBSD__ */ + #if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM) typedef struct FsMount { char *dirname; char *devtype; unsigned int devmajor, devminor; +#if defined(__FreeBSD__) + dev_t dev; + fsid_t fsid; +#endif QTAILQ_ENTRY(FsMount) next; } FsMount; diff --git a/qga/commands-posix.c b/qga/commands-posix.c index d24f2fafd8..6875ea8888 100644 --- a/qga/commands-posix.c +++ b/qga/commands-posix.c @@ -33,20 +33,12 @@ #if defined(__linux__) #include -#include #include #include #ifdef CONFIG_LIBUDEV #include #endif - -#ifdef FIFREEZE -#define CONFIG_FSFREEZE -#endif -#ifdef FITRIM -#define CONFIG_FSTRIM -#endif #endif #ifdef __FreeBSD__ @@ -623,9 +615,6 @@ void qmp_guest_file_flush(int64_t handle, Error **errp) } } -/* linux-specific implementations. avoid this if at all possible. */ -#if defined(__linux__) - #if defined(CONFIG_FSFREEZE) || defined(CONFIG_FSTRIM) void free_fs_mount_list(FsMountList *mounts) { @@ -644,6 +633,156 @@ void free_fs_mount_list(FsMountList *mounts) } #endif +#if defined(CONFIG_FSFREEZE) +typedef enum { + FSFREEZE_HOOK_THAW = 0, + FSFREEZE_HOOK_FREEZE, +} FsfreezeHookArg; + +static const char *fsfreeze_hook_arg_string[] = { + "thaw", + "freeze", +}; + +static void execute_fsfreeze_hook(FsfreezeHookArg arg, Error **errp) +{ + int status; + pid_t pid; + const char *hook; + const char *arg_str = fsfreeze_hook_arg_string[arg]; + Error *local_err = NULL; + + hook = ga_fsfreeze_hook(ga_state); + if (!hook) { + return; + } + if (access(hook, X_OK) != 0) { + error_setg_errno(errp, errno, "can't access fsfreeze hook '%s'", hook); + return; + } + + slog("executing fsfreeze hook with arg '%s'", arg_str); + pid = fork(); + if (pid == 0) { + setsid(); + reopen_fd_to_null(0); + reopen_fd_to_null(1); + reopen_fd_to_null(2); + + execl(hook, hook, arg_str, NULL); + _exit(EXIT_FAILURE); + } else if (pid < 0) { + error_setg_errno(errp, errno, "failed to create child process"); + return; + } + + ga_wait_child(pid, &status, &local_err); + if (local_err) { + error_propagate(errp, local_err); + return; + } + + if (!WIFEXITED(status)) { + error_setg(errp, "fsfreeze hook has terminated abnormally"); + return; + } + + status = WEXITSTATUS(status); + if (status) { + error_setg(errp, "fsfreeze hook has failed with status %d", status); + return; + } +} + +/* + * Return status of freeze/thaw + */ +GuestFsfreezeStatus qmp_guest_fsfreeze_status(Error **errp) +{ + if (ga_is_frozen(ga_state)) { + return GUEST_FSFREEZE_STATUS_FROZEN; + } + + return GUEST_FSFREEZE_STATUS_THAWED; +} + +int64_t qmp_guest_fsfreeze_freeze(Error **errp) +{ + return qmp_guest_fsfreeze_freeze_list(false, NULL, errp); +} + +int64_t qmp_guest_fsfreeze_freeze_list(bool has_mountpoints, + strList *mountpoints, + Error **errp) +{ + int ret; + FsMountList mounts; + Error *local_err = NULL; + + slog("guest-fsfreeze called"); + + execute_fsfreeze_hook(FSFREEZE_HOOK_FREEZE, &local_err); + if (local_err) { + error_propagate(errp, local_err); + return -1; + } + + QTAILQ_INIT(&mounts); + if (!build_fs_mount_list(&mounts, &local_err)) { + error_propagate(errp, local_err); + return -1; + } + + /* cannot risk guest agent blocking itself on a write in this state */ + ga_set_frozen(ga_state); + + 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 (ret == 0) { + ga_unset_frozen(ga_state); + } else if (ret < 0) { + qmp_guest_fsfreeze_thaw(NULL); + } + return ret; +} + +int64_t qmp_guest_fsfreeze_thaw(Error **errp) +{ + int ret; + + 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; + } + + return ret; +} + +static void guest_fsfreeze_cleanup(void) +{ + Error *err = NULL; + + if (ga_is_frozen(ga_state) == GUEST_FSFREEZE_STATUS_FROZEN) { + qmp_guest_fsfreeze_thaw(&err); + if (err) { + slog("failed to clean up frozen filesystems: %s", + error_get_pretty(err)); + error_free(err); + } + } +} +#endif + +/* linux-specific implementations. avoid this if at all possible. */ +#if defined(__linux__) #if defined(CONFIG_FSFREEZE) static char *get_pci_driver(char const *syspath, int pathlen, Error **errp) @@ -1467,153 +1606,6 @@ GuestFilesystemInfoList *qmp_guest_get_fsinfo(Error **errp) free_fs_mount_list(&mounts); return ret; } - - -typedef enum { - FSFREEZE_HOOK_THAW = 0, - FSFREEZE_HOOK_FREEZE, -} FsfreezeHookArg; - -static const char *fsfreeze_hook_arg_string[] = { - "thaw", - "freeze", -}; - -static void execute_fsfreeze_hook(FsfreezeHookArg arg, Error **errp) -{ - int status; - pid_t pid; - const char *hook; - const char *arg_str = fsfreeze_hook_arg_string[arg]; - Error *local_err = NULL; - - hook = ga_fsfreeze_hook(ga_state); - if (!hook) { - return; - } - if (access(hook, X_OK) != 0) { - error_setg_errno(errp, errno, "can't access fsfreeze hook '%s'", hook); - return; - } - - slog("executing fsfreeze hook with arg '%s'", arg_str); - pid = fork(); - if (pid == 0) { - setsid(); - reopen_fd_to_null(0); - reopen_fd_to_null(1); - reopen_fd_to_null(2); - - execl(hook, hook, arg_str, NULL); - _exit(EXIT_FAILURE); - } else if (pid < 0) { - error_setg_errno(errp, errno, "failed to create child process"); - return; - } - - ga_wait_child(pid, &status, &local_err); - if (local_err) { - error_propagate(errp, local_err); - return; - } - - if (!WIFEXITED(status)) { - error_setg(errp, "fsfreeze hook has terminated abnormally"); - return; - } - - status = WEXITSTATUS(status); - if (status) { - error_setg(errp, "fsfreeze hook has failed with status %d", status); - return; - } -} - -/* - * Return status of freeze/thaw - */ -GuestFsfreezeStatus qmp_guest_fsfreeze_status(Error **errp) -{ - if (ga_is_frozen(ga_state)) { - return GUEST_FSFREEZE_STATUS_FROZEN; - } - - return GUEST_FSFREEZE_STATUS_THAWED; -} - -int64_t qmp_guest_fsfreeze_freeze(Error **errp) -{ - return qmp_guest_fsfreeze_freeze_list(false, NULL, errp); -} - -int64_t qmp_guest_fsfreeze_freeze_list(bool has_mountpoints, - strList *mountpoints, - Error **errp) -{ - int ret; - FsMountList mounts; - Error *local_err = NULL; - - slog("guest-fsfreeze called"); - - execute_fsfreeze_hook(FSFREEZE_HOOK_FREEZE, &local_err); - if (local_err) { - error_propagate(errp, local_err); - return -1; - } - - QTAILQ_INIT(&mounts); - if (!build_fs_mount_list(&mounts, &local_err)) { - error_propagate(errp, local_err); - return -1; - } - - /* cannot risk guest agent blocking itself on a write in this state */ - ga_set_frozen(ga_state); - - 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 (ret == 0) { - ga_unset_frozen(ga_state); - } else if (ret < 0) { - qmp_guest_fsfreeze_thaw(NULL); - } - return ret; -} - -int64_t qmp_guest_fsfreeze_thaw(Error **errp) -{ - int ret; - - 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; - } - - return ret; -} - -static void guest_fsfreeze_cleanup(void) -{ - Error *err = NULL; - - if (ga_is_frozen(ga_state) == GUEST_FSFREEZE_STATUS_FROZEN) { - qmp_guest_fsfreeze_thaw(&err); - if (err) { - slog("failed to clean up frozen filesystems: %s", - error_get_pretty(err)); - error_free(err); - } - } -} #endif /* CONFIG_FSFREEZE */ #if defined(CONFIG_FSTRIM) diff --git a/qga/main.c b/qga/main.c index 0d27c97d38..b3580508fa 100644 --- a/qga/main.c +++ b/qga/main.c @@ -37,12 +37,7 @@ #include "qga/service-win32.h" #include "qga/vss-win32.h" #endif -#ifdef __linux__ -#include -#ifdef FIFREEZE -#define CONFIG_FSFREEZE -#endif -#endif +#include "commands-common.h" #ifndef _WIN32 #ifdef __FreeBSD__ diff --git a/qga/meson.build b/qga/meson.build index 932b4e7ca8..3cfb9166e5 100644 --- a/qga/meson.build +++ b/qga/meson.build @@ -75,6 +75,9 @@ qga_ss.add(when: 'CONFIG_POSIX', if_true: files( qga_ss.add(when: 'CONFIG_LINUX', if_true: files( 'commands-linux.c', )) +qga_ss.add(when: 'CONFIG_BSD', if_true: files( + 'commands-bsd.c', +)) qga_ss.add(when: 'CONFIG_WIN32', if_true: files( 'channel-win32.c', 'commands-win32.c',