fstab-generator: if usr= is specified, mount it to /sysusr/usr/ first

This changes the fstab-generator to handle mounting of /usr/ a bit
differently than before. Instead of immediately mounting the fs to
/sysroot/usr/ we'll first mount it to /sysusr/usr/ and then add a
separate bind mount that mounts it from /sysusr/usr/ to /sysroot/usr/.

This way we can access /usr independently of the root fs, without for
waiting to be mounted via the /sysusr/ hierarchy. This is useful for
invoking systemd-repart while a root fs doesn't exist yet and for
creating it, with partition data read from the /usr/ hierarchy.

This introduces a new generic target initrd-usr-fs.target that may be
used to generically order services against /sysusr/ to become available.
This commit is contained in:
Lennart Poettering
2021-04-20 18:26:17 +02:00
parent ee7561d014
commit 29a24ab28e
7 changed files with 100 additions and 17 deletions
+1
View File
@@ -37,6 +37,7 @@
#define SPECIAL_INITRD_FS_TARGET "initrd-fs.target"
#define SPECIAL_INITRD_ROOT_DEVICE_TARGET "initrd-root-device.target"
#define SPECIAL_INITRD_ROOT_FS_TARGET "initrd-root-fs.target"
#define SPECIAL_INITRD_USR_FS_TARGET "initrd-usr-fs.target"
#define SPECIAL_REMOTE_FS_TARGET "remote-fs.target" /* LSB's $remote_fs */
#define SPECIAL_REMOTE_FS_PRE_TARGET "remote-fs-pre.target"
#define SPECIAL_SWAP_TARGET "swap.target"