Merge pull request #21070 from medhefgo/boot-save

sd-boot: Add support to boot last select entry

man/bootctl.xml

@@ -99,8 +99,8 @@
         <term><option>set-default</option> <replaceable>ID</replaceable></term>
         <term><option>set-oneshot</option> <replaceable>ID</replaceable></term>
 
-        <listitem><para>Sets the default boot loader entry. Takes a single boot loader entry ID string as
+        <listitem><para>Sets the default boot loader entry. Takes a single boot loader entry ID string or a glob
-        argument. The <option>set-oneshot</option> command will set the default entry only for the next boot,
+        pattern as argument. The <option>set-oneshot</option> command will set the default entry only for the next boot,
         the <option>set-default</option> will set it persistently for all future boots.</para></listitem>
 
         <listitem><para>Optionally, the boot loader entry ID may be specified as one of: <option>@default</option>,
@@ -111,8 +111,12 @@
         see <ulink url="https://systemd.io/BOOT_LOADER_SPECIFICATION">Boot Loader Specification</ulink> for details.
         These special IDs are primarily useful as a quick way to persistently make the currently booted boot loader
         entry the default choice, or to upgrade the default boot loader entry for the next boot to the default boot
-        loader entry for all future boots, but may be used for other operations too.
+        loader entry for all future boots, but may be used for other operations too.</para>
-        When an empty string ("") is specified as an ID, then the corresponding EFI variable will be unset.
+
+        <para>If set to <option>@saved</option> the chosen entry will be saved as an EFI variable
+        on every boot and automatically selected the next time the boot loader starts.</para>
+
+        <para>When an empty string ("") is specified as an ID, then the corresponding EFI variable will be unset.
         </para></listitem>
       </varlistentry>
 

man/loader.conf.xml

@@ -60,6 +60,9 @@
         selected entry will be stored as an EFI variable, overriding this option.
         </para>
 
+        <para>If set to <literal>@saved</literal> the chosen entry will be saved as an EFI variable
+        on every boot and automatically selected the next time the boot loader starts.</para>
+
         <table>
           <title>Automatically detected entries will use the following names:</title>
 

src/boot/bootctl.c

@@ -1834,7 +1834,7 @@ static int parse_loader_entry_target_arg(const char *arg1, char16_t **ret_target
                 if (r < 0)
                         return log_error_errno(r, "Failed to get EFI variable 'LoaderEntryDefault': %m");
 
-        } else if (arg1[0] == '@')
+        } else if (arg1[0] == '@' && !streq(arg1, "@saved"))
                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Unsupported special entry identifier: %s", arg1);
         else {
                 encoded = utf8_to_utf16(arg1, strlen(arg1));

src/boot/efi/boot.c

@@ -67,13 +67,17 @@ typedef struct {
         UINT32 timeout_sec; /* Actual timeout used (efi_main() override > efivar > config). */
         UINT32 timeout_sec_config;
         UINT32 timeout_sec_efivar;
-        CHAR16 *entry_default_pattern;
+        CHAR16 *entry_default_config;
+        CHAR16 *entry_default_efivar;
         CHAR16 *entry_oneshot;
+        CHAR16 *entry_saved;
         CHAR16 *options_edit;
         BOOLEAN editor;
         BOOLEAN auto_entries;
         BOOLEAN auto_firmware;
         BOOLEAN force_menu;
+        BOOLEAN use_saved_entry;
+        BOOLEAN use_saved_entry_efivar;
         INT64 console_mode;
         INT64 console_mode_efivar;
         RandomSeedMode random_seed_mode;
@@ -435,7 +439,7 @@ static void print_status(Config *config, CHAR16 *loaded_image_path) {
         UINT64 key;
         UINTN x_max, y_max;
         SecureBootMode secure;
-        _cleanup_freepool_ CHAR16 *device_part_uuid = NULL, *default_efivar = NULL;
+        _cleanup_freepool_ CHAR16 *device_part_uuid = NULL;
 
         assert(config);
         assert(loaded_image_path);
@@ -445,7 +449,6 @@ static void print_status(Config *config, CHAR16 *loaded_image_path) {
 
         secure = secure_boot_mode();
         (void) efivar_get(LOADER_GUID, L"LoaderDevicePartUUID", &device_part_uuid);
-        (void) efivar_get(LOADER_GUID, L"LoaderEntryDefault", &default_efivar);
 
         /* We employ some unusual indentation here for readability. */
 
@@ -486,9 +489,10 @@ static void print_status(Config *config, CHAR16 *loaded_image_path) {
             Print(L"     timeout (EFI var): %lu s\n", config->timeout_sec_efivar);
         }
 
-        ps_string(L"               default: %s\n", config->entry_default_pattern);
+        ps_string(L"               default: %s\n", config->entry_default_config);
+        ps_string(L"     default (EFI var): %s\n", config->entry_default_efivar);
         ps_string(L"    default (one-shot): %s\n", config->entry_oneshot);
-        ps_string(L"     default (EFI var): %s\n", default_efivar);
+        ps_string(L"           saved entry: %s\n", config->entry_saved);
           ps_bool(L"                editor: %s\n", config->editor);
           ps_bool(L"          auto-entries: %s\n", config->auto_entries);
           ps_bool(L"         auto-firmware: %s\n", config->auto_firmware);
@@ -586,6 +590,7 @@ static BOOLEAN menu_run(
         INT16 idx;
         BOOLEAN exit = FALSE, run = TRUE, firmware_setup = FALSE;
         INT64 console_mode_initial = ST->ConOut->Mode->Mode, console_mode_efivar_saved = config->console_mode_efivar;
+        INTN default_efivar_saved = config->idx_default_efivar;
 
         graphics_mode(FALSE);
         ST->ConIn->Reset(ST->ConIn, FALSE);
@@ -831,20 +836,20 @@ static BOOLEAN menu_run(
                 case KEYPRESS(0, 0, 'd'):
                 case KEYPRESS(0, 0, 'D'):
                         if (config->idx_default_efivar != (INTN)idx_highlight) {
-                                /* store the selected entry in a persistent EFI variable */
+                                FreePool(config->entry_default_efivar);
-                                efivar_set(
+                                config->entry_default_efivar = StrDuplicate(config->entries[idx_highlight]->id);
-                                        LOADER_GUID,
+                                if (!config->entry_default_efivar) {
-                                        L"LoaderEntryDefault",
+                                        log_oom();
-                                        config->entries[idx_highlight]->id,
+                                        return FALSE;
-                                        EFI_VARIABLE_NON_VOLATILE);
+                                }
                                 config->idx_default_efivar = idx_highlight;
                                 status = StrDuplicate(L"Default boot entry selected.");
                         } else {
-                                /* clear the default entry EFI variable */
+                                config->entry_default_efivar = mfree(config->entry_default_efivar);
-                                efivar_set(LOADER_GUID, L"LoaderEntryDefault", NULL, EFI_VARIABLE_NON_VOLATILE);
                                 config->idx_default_efivar = -1;
                                 status = StrDuplicate(L"Default boot entry cleared.");
                         }
+                        config->use_saved_entry_efivar = FALSE;
                         refresh = TRUE;
                         break;
 
@@ -954,6 +959,9 @@ static BOOLEAN menu_run(
 
         /* Update EFI vars after we left the menu to reduce NVRAM writes. */
 
+        if (default_efivar_saved != config->idx_default_efivar)
+                efivar_set(LOADER_GUID, L"LoaderEntryDefault", config->entry_default_efivar, EFI_VARIABLE_NON_VOLATILE);
+
         if (console_mode_efivar_saved != config->console_mode_efivar) {
                 if (config->console_mode_efivar == CONSOLE_MODE_KEEP)
                         efivar_set(LOADER_GUID, L"LoaderConfigConsoleMode", NULL, EFI_VARIABLE_NON_VOLATILE);
@@ -1109,9 +1117,12 @@ static void config_defaults_load_from_file(Config *config, CHAR8 *content) {
                 }
 
                 if (strcmpa((CHAR8 *)"default", key) == 0) {
-                        FreePool(config->entry_default_pattern);
+                        if (value[0] == '@' && strcmpa((CHAR8 *)"@saved", value) != 0) {
-                        config->entry_default_pattern = stra_to_str(value);
+                                log_error_stall(L"Unsupported special entry identifier: %a", value);
-                        StrLwr(config->entry_default_pattern);
+                                continue;
+                        }
+                        FreePool(config->entry_default_config);
+                        config->entry_default_config = stra_to_str(value);
                         continue;
                 }
 
@@ -1537,6 +1548,18 @@ static void config_load_defaults(Config *config, EFI_FILE *root_dir) {
         err = efivar_get_uint_string(LOADER_GUID, L"LoaderConfigConsoleMode", &value);
         if (!EFI_ERROR(err))
                 config->console_mode_efivar = value;
+
+        err = efivar_get(LOADER_GUID, L"LoaderEntryOneShot", &config->entry_oneshot);
+        if (!EFI_ERROR(err))
+                /* Unset variable now, after all it's "one shot". */
+                (void) efivar_set(LOADER_GUID, L"LoaderEntryOneShot", NULL, EFI_VARIABLE_NON_VOLATILE);
+
+        (void) efivar_get(LOADER_GUID, L"LoaderEntryDefault", &config->entry_default_efivar);
+
+        config->use_saved_entry = streq_ptr(config->entry_default_config, L"@saved");
+        config->use_saved_entry_efivar = streq_ptr(config->entry_default_efivar, L"@saved");
+        if (config->use_saved_entry || config->use_saved_entry_efivar)
+                (void) efivar_get(LOADER_GUID, L"LoaderEntryLastBooted", &config->entry_saved);
 }
 
 static void config_load_entries(
@@ -1622,69 +1645,45 @@ static void config_sort_entries(Config *config) {
         sort_pointer_array((void**) config->entries, config->entry_count, (compare_pointer_func_t) config_entry_compare);
 }
 
-static INTN config_entry_find(Config *config, CHAR16 *id) {
+static INTN config_entry_find(Config *config, CHAR16 *needle) {
         assert(config);
-        assert(id);
+
+        if (!needle)
+                return -1;
 
         for (UINTN i = 0; i < config->entry_count; i++)
-                if (StrCmp(config->entries[i]->id, id) == 0)
+                if (MetaiMatch(config->entries[i]->id, needle))
                         return (INTN) i;
 
         return -1;
 }
 
 static void config_default_entry_select(Config *config) {
-        _cleanup_freepool_ CHAR16 *entry_default = NULL;
-        EFI_STATUS err;
         INTN i;
 
         assert(config);
 
-        /*
+        i = config_entry_find(config, config->entry_oneshot);
-         * The EFI variable to specify a boot entry for the next, and only the
+        if (i >= 0) {
-         * next reboot. The variable is always cleared directly after it is read.
+                config->idx_default = i;
-         */
-        err = efivar_get(LOADER_GUID, L"LoaderEntryOneShot", &config->entry_oneshot);
-        if (!EFI_ERROR(err)) {
-                efivar_set(LOADER_GUID, L"LoaderEntryOneShot", NULL, EFI_VARIABLE_NON_VOLATILE);
-
-                i = config_entry_find(config, config->entry_oneshot);
-                if (i >= 0) {
-                        config->idx_default = i;
-                        return;
-                }
-        }
-
-        /*
-         * The EFI variable to select the default boot entry overrides the
-         * configured pattern. The variable can be set and cleared by pressing
-         * the 'd' key in the loader selection menu.
-         */
-        err = efivar_get(LOADER_GUID, L"LoaderEntryDefault", &entry_default);
-        if (!EFI_ERROR(err)) {
-                i = config_entry_find(config, entry_default);
-                if (i >= 0) {
-                        config->idx_default = i;
-                        config->idx_default_efivar = i;
-                        return;
-                }
-        }
-
-        if (config->entry_count == 0)
                 return;
+        }
 
-        /*
+        i = config_entry_find(config, config->use_saved_entry_efivar ? config->entry_saved : config->entry_default_efivar);
-         * Match the pattern from the end of the list to the start, find last
+        if (i >= 0) {
-         * entry (largest number) matching the given pattern.
+                config->idx_default = i;
-         */
+                config->idx_default_efivar = i;
-        if (config->entry_default_pattern) {
+                return;
-                i = config->entry_count;
+        }
-                while (i--) {
+
-                        if (MetaiMatch(config->entries[i]->id, config->entry_default_pattern)) {
+        if (config->use_saved_entry)
-                                config->idx_default = i;
+                /* No need to do the same thing twice. */
-                                return;
+                i = config->use_saved_entry_efivar ? -1 : config_entry_find(config, config->entry_saved);
-                        }
+        else
-                }
+                i = config_entry_find(config, config->entry_default_config);
+        if (i >= 0) {
+                config->idx_default = i;
+                return;
         }
 
         /* select the last suitable entry */
@@ -2224,7 +2223,7 @@ static void config_free(Config *config) {
         for (UINTN i = 0; i < config->entry_count; i++)
                 config_entry_free(config->entries[i]);
         FreePool(config->entries);
-        FreePool(config->entry_default_pattern);
+        FreePool(config->entry_default_config);
         FreePool(config->options_edit);
         FreePool(config->entry_oneshot);
 }
@@ -2256,6 +2255,29 @@ static void config_write_entries_to_variable(Config *config) {
         (void) efivar_set_raw(LOADER_GUID, L"LoaderEntries", buffer, sz, 0);
 }
 
+static void save_selected_entry(const Config *config, const ConfigEntry *entry) {
+        assert(config);
+        assert(entry);
+        assert(!entry->call);
+
+        /* Always export the selected boot entry to the system in a volatile var. */
+        (void) efivar_set(LOADER_GUID, L"LoaderEntrySelected", entry->id, 0);
+
+        /* Do not save or delete if this was a oneshot boot. */
+        if (streq_ptr(config->entry_oneshot, entry->id))
+                return;
+
+        if (config->use_saved_entry_efivar || (!config->entry_default_efivar && config->use_saved_entry)) {
+                /* Avoid unnecessary NVRAM writes. */
+                if (streq_ptr(config->entry_saved, entry->id))
+                        return;
+
+                (void) efivar_set(LOADER_GUID, L"LoaderEntryLastBooted", entry->id, EFI_VARIABLE_NON_VOLATILE);
+        } else
+                /* Delete the non-volatile var if not needed. */
+                (void) efivar_set(LOADER_GUID, L"LoaderEntryLastBooted", NULL, EFI_VARIABLE_NON_VOLATILE);
+}
+
 static void export_variables(
                 EFI_LOADED_IMAGE *loaded_image,
                 const CHAR16 *loaded_image_path,
@@ -2434,9 +2456,7 @@ EFI_STATUS efi_main(EFI_HANDLE image, EFI_SYSTEM_TABLE *sys_table) {
                 }
 
                 config_entry_bump_counters(entry, root_dir);
-
+                save_selected_entry(&config, entry);
-                /* Export the selected boot entry to the system */
-                (void) efivar_set(LOADER_GUID, L"LoaderEntrySelected", entry->id, 0);
 
                 /* Optionally, read a random seed off the ESP and pass it to the OS */
                 (void) process_random_seed(root_dir, config.random_seed_mode);