man/systemd-vmspawn.xml

@@ -125,17 +125,6 @@
           <xi:include href="version-info.xml" xpointer="v260"/></listitem>
         </varlistentry>
 
-        <varlistentry>
-          <term><option>-x</option></term>
-          <term><option>--ephemeral</option></term>
-
-          <listitem><para>If specified, the VM is run with a temporary snapshot of its file system that is removed
-          immediately when the VM terminates. Only works with <option>--image=</option> currently.
-
-          Note that <option>--ephemeral</option> will not work with <option>--extra-drive=</option>.</para>
-
-          <xi:include href="version-info.xml" xpointer="v260"/></listitem>
-        </varlistentry>
       </variablelist>
     </refsect2>
 

src/nspawn/nspawn.c

@@ -107,7 +107,6 @@
 #include "shift-uid.h"
 #include "signal-util.h"
 #include "siphash24.h"
-#include "snapshot-util.h"
 #include "socket-util.h"
 #include "stat-util.h"
 #include "stdio-util.h"
@@ -5916,7 +5915,7 @@ static int do_cleanup(void) {
 }
 
 static int run(int argc, char *argv[]) {
-        bool remove_image = false, veth_created = false;
+        bool remove_directory = false, remove_image = false, veth_created = false;
         _cleanup_close_ int master = -EBADF, userns_fd = -EBADF, mount_fd = -EBADF;
         _cleanup_fdset_free_ FDSet *fds = NULL;
         int r, ret = EXIT_SUCCESS;
@@ -5924,7 +5923,6 @@ static int run(int argc, char *argv[]) {
         struct ExposeArgs expose_args = {};
         _cleanup_(release_lock_file) LockFile tree_global_lock = LOCK_FILE_INIT, tree_local_lock = LOCK_FILE_INIT;
         _cleanup_(rmdir_and_freep) char *rootdir = NULL;
-        _cleanup_(rm_rf_subvolume_and_freep) char *snapshot_dir = NULL;
         _cleanup_(loop_device_unrefp) LoopDevice *loop = NULL;
         _cleanup_(dissected_image_unrefp) DissectedImage *dissected_image = NULL;
         _cleanup_(sd_netlink_unrefp) sd_netlink *nfnl = NULL;
@@ -6066,27 +6064,63 @@ static int run(int argc, char *argv[]) {
                 }
 
                 if (arg_ephemeral) {
+                        _cleanup_free_ char *np = NULL;
+
                         r = chase_and_update(&arg_directory, 0);
                         if (r < 0)
                                 goto finish;
 
-                        r = create_ephemeral_snapshot(
-                                        arg_directory,
-                                        arg_privileged ? RUNTIME_SCOPE_SYSTEM : RUNTIME_SCOPE_USER,
-                                        arg_read_only,
-                                        &tree_global_lock,
-                                        &tree_local_lock,
-                                        &snapshot_dir);
+                        /* If the specified path is a mount point we generate the new snapshot immediately
+                         * inside it under a random name. However if the specified is not a mount point we
+                         * create the new snapshot in the parent directory, just next to it. */
+                        r = path_is_mount_point(arg_directory);
                         if (r < 0) {
-                                log_error_errno(r, "Failed to create ephemeral snapshot: %m");
+                                log_error_errno(r, "Failed to determine whether directory %s is mount point: %m", arg_directory);
+                                goto finish;
+                        }
+                        if (r > 0)
+                                r = tempfn_random_child(arg_directory, "machine.", &np);
+                        else
+                                r = tempfn_random(arg_directory, "machine.", &np);
+                        if (r < 0) {
+                                log_error_errno(r, "Failed to generate name for directory snapshot: %m");
                                 goto finish;
                         }
 
-                        r = free_and_strdup(&arg_directory, snapshot_dir);
+                        /* We take an exclusive lock on this image, since it's our private, ephemeral copy
+                         * only owned by us and no one else. */
+                        r = image_path_lock(
+                                        arg_privileged ? RUNTIME_SCOPE_SYSTEM : RUNTIME_SCOPE_USER,
+                                        np,
+                                        LOCK_EX|LOCK_NB,
+                                        arg_privileged ? &tree_global_lock : NULL,
+                                        &tree_local_lock);
                         if (r < 0) {
-                                log_oom();
+                                log_error_errno(r, "Failed to lock %s: %m", np);
                                 goto finish;
                         }
+
+                        {
+                                BLOCK_SIGNALS(SIGINT);
+                                r = btrfs_subvol_snapshot_at(AT_FDCWD, arg_directory, AT_FDCWD, np,
+                                                             (arg_read_only ? BTRFS_SNAPSHOT_READ_ONLY : 0) |
+                                                             BTRFS_SNAPSHOT_FALLBACK_COPY |
+                                                             BTRFS_SNAPSHOT_FALLBACK_DIRECTORY |
+                                                             BTRFS_SNAPSHOT_RECURSIVE |
+                                                             BTRFS_SNAPSHOT_QUOTA |
+                                                             BTRFS_SNAPSHOT_SIGINT);
+                        }
+                        if (r == -EINTR) {
+                                log_error_errno(r, "Interrupted while copying file system tree to %s, removed again.", np);
+                                goto finish;
+                        }
+                        if (r < 0) {
+                                log_error_errno(r, "Failed to create snapshot %s from %s: %m", np, arg_directory);
+                                goto finish;
+                        }
+
+                        free_and_replace(arg_directory, np);
+                        remove_directory = true;
                 } else {
                         r = chase_and_update(&arg_directory, arg_template ? CHASE_NONEXISTENT : 0);
                         if (r < 0)
@@ -6437,6 +6471,14 @@ finish:
 
         pager_close();
 
+        if (remove_directory && arg_directory) {
+                int k;
+
+                k = rm_rf(arg_directory, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME);
+                if (k < 0)
+                        log_warning_errno(k, "Cannot remove '%s', ignoring: %m", arg_directory);
+        }
+
         if (remove_image && arg_image) {
                 if (unlink(arg_image) < 0)
                         log_warning_errno(errno, "Can't remove image file '%s', ignoring: %m", arg_image);

src/shared/meson.build

@@ -177,7 +177,6 @@ shared_sources = files(
         'sleep-config.c',
         'smack-util.c',
         'smbios11.c',
-        'snapshot-util.c',
         'socket-label.c',
         'socket-netlink.c',
         'specifier.c',

src/shared/snapshot-util.c

@@ -1,65 +0,0 @@
-/* SPDX-License-Identifier: LGPL-2.1-or-later */
-
-#include <sys/file.h>
-
-#include "alloc-util.h"
-#include "btrfs-util.h"
-#include "discover-image.h"
-#include "log.h"
-#include "mountpoint-util.h"
-#include "snapshot-util.h"
-#include "signal-util.h"
-#include "tmpfile-util.h"
-
-int create_ephemeral_snapshot(
-                const char *directory,
-                RuntimeScope scope,
-                bool read_only,
-                LockFile *tree_global_lock,
-                LockFile *tree_local_lock,
-                char **ret_new_path) {
-
-        _cleanup_free_ char *np = NULL;
-        int r;
-
-        /* If the specified path is a mount point we generate the new snapshot immediately
-         * inside it under a random name. However if the specified is not a mount point we
-         * create the new snapshot in the parent directory, just next to it. */
-        r = path_is_mount_point(directory);
-        if (r < 0)
-                return log_debug_errno(r, "Failed to determine whether directory %s is mount point: %m", directory);
-        if (r > 0)
-                r = tempfn_random_child(directory, "snapshot.", &np);
-        else
-                r = tempfn_random(directory, "snapshot.", &np);
-        if (r < 0)
-                return log_debug_errno(r, "Failed to generate name for directory snapshot: %m");
-
-        /* We take an exclusive lock on this image, since it's our private, ephemeral copy
-         * only owned by us and no one else. */
-        r = image_path_lock(
-                        scope,
-                        np,
-                        LOCK_EX|LOCK_NB,
-                        scope == RUNTIME_SCOPE_SYSTEM ? tree_global_lock : NULL,
-                        tree_local_lock);
-        if (r < 0)
-                return log_debug_errno(r, "Failed to lock %s: %m", np);
-
-        {
-                BLOCK_SIGNALS(SIGINT);
-                r = btrfs_subvol_snapshot_at(AT_FDCWD, directory, AT_FDCWD, np,
-                                             (read_only ? BTRFS_SNAPSHOT_READ_ONLY : 0) |
-                                             BTRFS_SNAPSHOT_FALLBACK_COPY |
-                                             BTRFS_SNAPSHOT_FALLBACK_DIRECTORY |
-                                             BTRFS_SNAPSHOT_RECURSIVE |
-                                             BTRFS_SNAPSHOT_QUOTA |
-                                             BTRFS_SNAPSHOT_SIGINT);
-        }
-        if (r < 0)
-                return log_debug_errno(r, "Failed to create snapshot %s from %s: %m", np, directory);
-
-        *ret_new_path = TAKE_PTR(np);
-
-        return 0;
-}

src/shared/snapshot-util.h

@@ -1,21 +0,0 @@
-/* SPDX-License-Identifier: LGPL-2.1-or-later */
-#pragma once
-
-#include "runtime-scope.h"
-
-/* create_ephemeral_snapshot - create a snapshot of the given directory.
- *
- * It will use a btrfs snapshot when available with fallback to traditional dir copy. It will set the global
- * and local lock files based on the passed runtime scope. On success the new directory path is returned via
- * `ret_new_path`.
- *
- * The caller is responsible for the cleanup of the directory, using `_cleanup_(rm_rf_subvolume_and_freep)`
- * is recommended.
- */
-int create_ephemeral_snapshot(
-                const char *directory,
-                RuntimeScope scope,
-                bool read_only,
-                LockFile *tree_global_lock,
-                LockFile *tree_local_lock,
-                char **ret_new_path);

src/vmspawn/vmspawn-settings.h

@@ -35,7 +35,6 @@ typedef enum SettingsMask {
         SETTING_START_MODE        = UINT64_C(1) << 0,
         SETTING_MACHINE_ID        = UINT64_C(1) << 6,
         SETTING_BIND_MOUNTS       = UINT64_C(1) << 11,
-        SETTING_EPHEMERAL         = UINT64_C(1) << 24,
         SETTING_DIRECTORY         = UINT64_C(1) << 26,
         SETTING_CREDENTIALS       = UINT64_C(1) << 30,
         _SETTING_FORCE_ENUM_WIDTH = UINT64_MAX

src/vmspawn/vmspawn.c

@@ -62,7 +62,6 @@
 #include "random-util.h"
 #include "rm-rf.h"
 #include "signal-util.h"
-#include "snapshot-util.h"
 #include "socket-util.h"
 #include "stat-util.h"
 #include "stdio-util.h"
@@ -146,7 +145,6 @@ static char **arg_bind_user = NULL;
 static char *arg_bind_user_shell = NULL;
 static bool arg_bind_user_shell_copy = false;
 static char **arg_bind_user_groups = NULL;
-static bool arg_ephemeral = false;
 static RuntimeScope arg_runtime_scope = _RUNTIME_SCOPE_INVALID;
 
 STATIC_DESTRUCTOR_REGISTER(arg_directory, freep);
@@ -192,7 +190,6 @@ static int help(void) {
                "     --system              Interact with system manager\n"
                "\n%3$sImage:%4$s\n"
                "  -D --directory=PATH      Root directory for the VM\n"
-               "  -x --ephemeral           Run VM with snapshot of the disk or directory\n"
                "  -i --image=FILE|DEVICE   Root file system disk image or device for the VM\n"
                "     --image-format=FORMAT Specify disk image format (raw, qcow2; default: raw)\n"
                "\n%3$sHost Configuration:%4$s\n"
@@ -330,7 +327,6 @@ static int parse_argv(int argc, char *argv[]) {
                 { "no-pager",          no_argument,       NULL, ARG_NO_PAGER          },
                 { "image",             required_argument, NULL, 'i'                   },
                 { "image-format",      required_argument, NULL, ARG_IMAGE_FORMAT      },
-                { "ephemeral",         no_argument,       NULL, 'x'                   },
                 { "directory",         required_argument, NULL, 'D'                   },
                 { "machine",           required_argument, NULL, 'M'                   },
                 { "slice",             required_argument, NULL, 'S'                   },
@@ -386,7 +382,7 @@ static int parse_argv(int argc, char *argv[]) {
         assert(argv);
 
         optind = 0;
-        while ((c = getopt_long(argc, argv, "+hD:i:xM:nqs:G:S:", options, NULL)) >= 0)
+        while ((c = getopt_long(argc, argv, "+hD:i:M:nqs:G:S:", options, NULL)) >= 0)
                 switch (c) {
                 case 'h':
                         return help();
@@ -433,10 +429,6 @@ static int parse_argv(int argc, char *argv[]) {
                         }
                         break;
 
-                case 'x':
-                        arg_ephemeral = true;
-                        break;
-
                 case ARG_NO_PAGER:
                         arg_pager_flags |= PAGER_DISABLE;
                         break;
@@ -802,9 +794,6 @@ static int parse_argv(int argc, char *argv[]) {
         if (!strv_isempty(arg_bind_user_groups) && strv_isempty(arg_bind_user))
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot use --bind-user-group= without --bind-user=");
 
-        if (arg_ephemeral && arg_extra_drives.n_drives > 0)
-                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot use --ephemeral with --extra-drive=");
-
         if (argc > optind) {
                 arg_kernel_cmdline_extra = strv_copy(argv + optind);
                 if (!arg_kernel_cmdline_extra)
@@ -1854,8 +1843,6 @@ static int run_virtual_machine(int kvm_device_fd, int vhost_device_fd) {
         _cleanup_(ovmf_config_freep) OvmfConfig *ovmf_config = NULL;
         _cleanup_free_ char *qemu_binary = NULL, *mem = NULL, *kernel = NULL;
         _cleanup_(rm_rf_physical_and_freep) char *ssh_private_key_path = NULL, *ssh_public_key_path = NULL;
-        _cleanup_(rm_rf_subvolume_and_freep) char *snapshot_directory = NULL;
-        _cleanup_(release_lock_file) LockFile tree_global_lock = LOCK_FILE_INIT, tree_local_lock = LOCK_FILE_INIT;
         _cleanup_close_ int notify_sock_fd = -EBADF;
         _cleanup_strv_free_ char **cmdline = NULL;
         _cleanup_free_ int *pass_fds = NULL;
@@ -2332,8 +2319,7 @@ static int run_virtual_machine(int kvm_device_fd, int vhost_device_fd) {
                 if (!escaped_image)
                         return log_oom();
 
-                if (strv_extendf(&cmdline, "if=none,id=vmspawn,file=%s,format=%s,discard=%s,snapshot=%s",
-                                 escaped_image, image_format_to_string(arg_image_format), on_off(arg_discard_disk), on_off(arg_ephemeral)) < 0)
+                if (strv_extendf(&cmdline, "if=none,id=vmspawn,file=%s,format=%s,discard=%s", escaped_image, image_format_to_string(arg_image_format), on_off(arg_discard_disk)) < 0)
                         return log_oom();
 
                 _cleanup_free_ char *image_fn = NULL;
@@ -2380,21 +2366,6 @@ static int run_virtual_machine(int kvm_device_fd, int vhost_device_fd) {
                 if (!GREEDY_REALLOC(children, n_children + 1))
                         return log_oom();
 
-                if (arg_ephemeral) {
-                        r = create_ephemeral_snapshot(arg_directory,
-                                                      arg_runtime_scope,
-                                                      /* read-only */ false,
-                                                      &tree_global_lock,
-                                                      &tree_local_lock,
-                                                      &snapshot_directory);
-                        if (r < 0)
-                                return r;
-
-                        arg_directory = strdup(snapshot_directory);
-                        if (!arg_directory)
-                                return log_oom();
-                }
-
                 r = start_virtiofsd(
                                 unit,
                                 arg_directory,
@@ -3094,11 +3065,6 @@ static int determine_names(void) {
                         if (r < 0)
                                 return log_error_errno(r, "Failed to extract file name from '%s': %m", arg_directory);
                 }
-                /* Add a random suffix when this is an ephemeral machine, so that we can run many
-                 * instances at once without manually having to specify -M each time. */
-                if (arg_ephemeral)
-                        if (strextendf(&arg_machine, "-%016" PRIx64, random_u64()) < 0)
-                                return log_oom();
 
                 hostname_cleanup(arg_machine);
                 if (!hostname_is_valid(arg_machine, 0))