btrfs-device: add page (#5170)

pages/linux/btrfs-device.md

@@ -0,0 +1,24 @@
+# btrfs device
+
+> Manage devices in a btrfs filesystem.
+> More information: <https://btrfs.wiki.kernel.org/index.php/Manpage/btrfs-device>.
+
+- Add one or more devices to a btrfs filesystem:
+
+`sudo btrfs device add {{path/to/block_device1}} [{{path/to/block_device2}}] {{path/to/btrfs_filesystem}}`
+
+- Remove a device from a btrfs filesystem:
+
+`sudo btrfs device remove {{path/to/device|device_id}} [{{...}}]`
+
+- Display error statistics:
+
+`sudo btrfs device stats {{path/to/btrfs_filesystem}}`
+
+- Scan all disks and inform the kernel of all detected btrfs filesystems:
+
+`sudo btrfs device scan --all-devices`
+
+- Display detailed per-disk allocation statistics:
+
+`sudo btrfs device usage {{path/to/btrfs_filesystem}}`