blockdev: add page (#13922)

Co-authored-by: Managor <42655600+Managor@users.noreply.github.com>
Co-authored-by: Wiktor Perskawiec <git@spageektti.cc>

pages/linux/blockdev.md

@@ -0,0 +1,36 @@
+# blockdev
+
+> Manage, query, and manipulate block devices.
+> More information: <https://manned.org/blockdev>.
+
+- Print a report for all devices:
+
+`sudo blockdev --report`
+
+- Print a report for a specific device:
+
+`sudo blockdev --report {{/dev/sdXY}}`
+
+- Get the size of a device in 512-byte sectors:
+
+`sudo blockdev --getsz {{/dev/sdXY}}`
+
+- Set read-only:
+
+`sudo blockdev --setro {{/dev/sdXY}}`
+
+- Set read-write:
+
+`sudo blockdev --setrw {{/dev/sdXY}}`
+
+- Flush buffers:
+
+`sudo blockdev --flushbufs {{/dev/sdXY}}`
+
+- Get the physical block size:
+
+`sudo blockdev --getpbsz {{/dev/sdXY}}`
+
+- Set the read-ahead value to 128 sectors:
+
+`sudo blockdev --setra 128 {{/dev/sdXY}}`