storage: Improve handling of LUKS backed btrfs

Single-device btrfs volumes now behave like other filesystems:
Unmounting all subvolumes will automatically lock the LUKS device, and
mounting the first subvolume will automatically unlock it.

Options in /etc/crypttab are now maintained correctly for btrfs
volumes with multiple subvolumes. For example, the LUKS device is only
"noauto" when all of the subvolumes are also "noauto", and it is
readonly exactly when all of the subvolumes are readonly.

Cockpit can't unfortunately always know whether a locked LUKS device
is part of a single-device or multi-device btrfs volume.  (Because
UDisks2 only tracks one parent of a fstab entry, we would need to fix
that.) We assume that they are single-device volumes (because they are
more common, probably) and let the user mount their subvolumes
directly.

If the assumption turns out to have been wrong, the mount operation is
cleanly aborted.

pkg/storaged/block/create-pages.jsx

@@ -35,7 +35,8 @@ import { make_swap_card } from "../swap/swap.jsx";
 import { make_encryption_card } from "../crypto/encryption.jsx";
 import { make_btrfs_device_card } from "../btrfs/device.jsx";
 import { make_btrfs_filesystem_card } from "../btrfs/filesystem.jsx";
-import { make_btrfs_subvolume_pages } from "../btrfs/subvolume.jsx";
+import { make_btrfs_subvolume_pages, make_btrfs_subvolume_pages_from_child_config } from "../btrfs/subvolume.jsx";
+import { is_multi_device_btrfs_volume } from "../btrfs/utils.jsx";
 
 import { new_page } from "../pages.jsx";
 
@@ -59,7 +60,7 @@ export function make_block_page(parent, block, card) {
                       (fstab_config[2].indexOf("subvol=") >= 0 || fstab_config[2].indexOf("subvolid=") >= 0));
 
     const block_btrfs_blockdev = content_block && client.blocks_fsys_btrfs[content_block.path];
-    const single_device_volume = block_btrfs_blockdev && block_btrfs_blockdev.data.num_devices === 1;
+    const single_device_volume = !is_multi_device_btrfs_volume(content_block || block);
 
     if (client.blocks_ptable[block.path]) {
         make_partition_table_page(parent, block, card);
@@ -85,8 +86,14 @@ export function make_block_page(parent, block, card) {
             // can not happen unless there is a bug in the code above.
             console.error("Assertion failure: is_crypto == false");
         }
-        if (fstab_config.length > 0 && !is_btrfs) {
-            card = make_filesystem_card(card, block, null, fstab_config);
+        if (fstab_config.length > 0) {
+            if (is_btrfs) {
+                if (single_device_volume)
+                    card = make_btrfs_filesystem_card(card, block, null);
+                else
+                    card = make_locked_encrypted_data_card(card, block);
+            } else
+                card = make_filesystem_card(card, block, null, fstab_config);
         } else {
             card = make_locked_encrypted_data_card(card, block);
         }
@@ -124,6 +131,8 @@ export function make_block_page(parent, block, card) {
         const page = new_page(parent, card);
         if (block_btrfs_blockdev && single_device_volume)
             make_btrfs_subvolume_pages(page, block_btrfs_blockdev);
+        else if (!content_block && is_btrfs && single_device_volume)
+            make_btrfs_subvolume_pages_from_child_config(page, block);
         return page;
     }
 }

pkg/storaged/btrfs/filesystem.jsx

@@ -27,9 +27,9 @@ import { DescriptionList } from "@patternfly/react-core/dist/esm/components/Desc
 import {
     new_card, ChildrenTable, StorageCard, StorageDescription
 } from "../pages.jsx";
+import { format_dialog } from "../block/format-dialog.jsx";
 import { StorageUsageBar, StorageLink } from "../storage-controls.jsx";
 import { btrfs_device_usage, btrfs_is_volume_mounted } from "./utils.jsx";
-import { btrfs_device_actions } from "./device.jsx";
 import { rename_dialog } from "./volume.jsx";
 
 const _ = cockpit.gettext;
@@ -43,17 +43,18 @@ export function make_btrfs_filesystem_card(next, backing_block, content_block) {
     return new_card({
         title: _("btrfs filesystem"),
         next,
-        actions: btrfs_device_actions(backing_block, content_block),
+        actions: [
+            { title: _("Format"), action: () => format_dialog(client, backing_block.path), danger: true },
+        ],
         component: BtrfsFilesystemCard,
         props: { backing_block, content_block },
     });
 }
 
 const BtrfsFilesystemCard = ({ card, backing_block, content_block }) => {
-    const block_btrfs = client.blocks_fsys_btrfs[content_block.path];
+    const block_btrfs = content_block && client.blocks_fsys_btrfs[content_block.path];
     const uuid = block_btrfs && block_btrfs.data.uuid;
     const label = block_btrfs && block_btrfs.data.label;
-    const use = btrfs_device_usage(client, uuid, block_btrfs.path);
 
     // Changing the label is only supported when the device is not mounted
     // otherwise we will get btrfs filesystem error ERROR: device /dev/vda5 is
@@ -66,18 +67,22 @@ const BtrfsFilesystemCard = ({ card, backing_block, content_block }) => {
         <StorageCard card={card}>
             <CardBody>
                 <DescriptionList className="pf-m-horizontal-on-sm">
+                    { block_btrfs &&
                     <StorageDescription title={_("Label")}
-                                                value={label}
-                                                action={
-                                                    <StorageLink onClick={() => rename_dialog(block_btrfs, label)}
-                                                               excuse={is_mounted ? _("Btrfs volume is mounted") : null}>
-                                                        {_("edit")}
-                                                    </StorageLink>}
+                                        value={label}
+                                        action={
+                                            <StorageLink onClick={() => rename_dialog(block_btrfs, label)}
+                                                         excuse={is_mounted ? _("Btrfs volume is mounted") : null}>
+                                                {_("edit")}
+                                            </StorageLink>}
                     />
+                    }
+                    { content_block &&
                     <StorageDescription title={_("UUID")} value={content_block.IdUUID} />
+                    }
                     { block_btrfs &&
                     <StorageDescription title={_("Usage")}>
-                        <StorageUsageBar key="s" stats={use} />
+                        <StorageUsageBar key="s" stats={btrfs_device_usage(client, uuid, block_btrfs.path)} />
                     </StorageDescription>
                     }
                 </DescriptionList>