Lines Matching full:lower
26 non-directory objects may report an st_dev from the lower filesystem or
85 Upper and Lower
89 and a 'lower' filesystem. When a name exists in both filesystems, the
91 'lower' filesystem is either hidden or, in the case of directories,
94 It would be more correct to refer to an upper and lower 'directory
98 lower.
100 The lower filesystem can be any filesystem supported by Linux and does
101 not need to be writable. The lower filesystem can even be another
113 upper and lower filesystems and refers to a non-directory in either,
114 then the lower object is hidden - the name refers only to the upper
117 Where both upper and lower objects are directories, a merged directory
123 mount -t overlay overlay -olowerdir=/lower,upperdir=/upper,\
134 exists, else the lower.
138 directory only. These attributes of the lower directory are hidden.
143 By default, all access to the upper, lower and work directories is the
152 caller without certain key capabilities or lower privilege will not
157 caller can fill cache, then a lower privilege can read the directory
166 In order to support rm and rmdir without changing the lower
173 matching name in the lower level is ignored, and the whiteout itself
178 directory in the lower filesystem with the same name is ignored.
184 lower directories are each read and the name lists merged in the
185 obvious way (upper is read first, then lower - entries that already
210 underlying directory (upper or lower).
215 When renaming a directory that is on the lower layer or merged (i.e. the
265 indexed by the file handle of the lower inode and a file handle of the
270 lower directory. In that case, lookup returns an error and warns about
273 Because lower layer redirects cannot be verified with the index, enabling
282 files etc.) are presented either from the upper or lower filesystem as
283 appropriate. When a file in the lower filesystem is accessed in a way
285 some metadata etc., the file is first copied from the lower filesystem
297 data is copied from the lower to the upper filesystem. Finally any
317 compared to direct access on underlying lower or upper filesystems
324 b) check if mounting task would be allowed real operation on lower or
340 mount -t overlay overlay -olowerdir=/lower,upperdir=/upper,... /merged
344 cp -a /lower /upper
351 Multiple lower layers
354 Multiple lower layers can now be given using the colon (":") as a
362 The specified lower directories will be stacked beginning from the
384 Do not use metacopy=on with untrusted upper/lower directories. Otherwise
386 appropriate REDIRECT and METACOPY xattrs, and gain access to file on lower
400 Lower layers may be shared among several overlay mounts and that is indeed
401 a very common practice. An overlay mount may use the same lower layer
402 path as another overlay mount and it may use a lower layer path that is
403 beneath or above the path of another overlay lower layer path.
414 different lower layer path, is allowed, unless the "inodes index" feature
418 handle of the lower layer root directory, along with the UUID of the lower
421 the lower root directory file handle and lower filesystem UUID are compared
423 lower root origin, mount will fail with ESTALE. An overlayfs mount with
424 "inodes index" enabled will fail with EOPNOTSUPP if the lower filesystem
425 does not support NFS export, lower filesystem does not have a valid UUID or
429 mount time. So if same upper is mounted with different set of lower, mount
435 the copied layers will fail the verification of the lower root file handle.
447 done in the case when the file resides on a lower layer.
449 b) If a file residing on a lower layer is opened for read-only and then
461 If this feature is disabled, then rename(2) on a lower or merged directory
494 the upper or the lower trees.
502 behavior on offline changes of the underlying lower layer is different
505 On every copy_up, an NFS file handle of the lower inode, along with the
506 UUID of the lower filesystem, are encoded and stored in an extended
510 that found a lower directory at the lookup path or at the path pointed
512 that the found lower directory file handle and lower filesystem UUID
514 found lower directory does not match the stored origin, that directory
525 With the "nfs_export" feature, on copy_up of any lower object, an index
536 1. For a non-upper object, encode a lower file handle from lower inode
537 2. For an indexed object, encode a lower file handle from copy_up origin
542 - Header including path type information (e.g. lower/upper)
553 3. For a lower file handle, lookup the handle in index directory by name.
565 When overlay filesystem has multiple lower layers, a middle layer
566 directory may have a "redirect" to lower directory. Because middle layer
567 "redirects" are not indexed, a lower file handle that was encoded from the
569 layer directory. Similarly, a lower file handle that was encoded from a
572 directories that cannot be decoded from a lower file handle, these