volfs(7FS) File Systems volfs(7FS)NAMEvolfs - Volume Management file system
DESCRIPTION
Note - The Volume Management file system might not be included in
future Solaris releases.
volfs is the Volume Management file system rooted at root_dir. The
default location for root-dir is /vol, but this can be overridden using
the -d option of vold (see vold(1M)). This file system is maintained by
the Volume Management daemon, vold, and will be considered to be /vol
for this description. Refer to vold(1M) for details on how to use the
volfssmf(5) service.
Media and removable media devices (without media) can be accessed in a
logical manner (no association with a particular piece of hardware), or
a physical manner (associated with a particular piece of hardware).
Logical names for media are referred to through /vol/dsk and /vol/rdsk.
/vol/dsk provides block access to random access devices. /vol/rdsk pro‐
vides character access to random access devices.
The /vol/rdsk and /vol/dsk directories are mirrors of one another. Any
change to one is reflected in the other immediately. The dev_t for a
volume will be the same for both the block and character device.
The default permissions for /vol are mode=0555, owner=root, group=sys.
The default permissions for /vol/dsk and /vol/rdsk are mode=01777,
owner=root, group=sys.
Physical references to media or removable media devices (without
media) are obtained through /vol/dev. This hierarchy reflects the
structure of the /dev name space. The default permissions for all
directories in the /vol/dev hierarchy are mode=0555, owner=root,
group=sys.
mkdir(2), rmdir(2), unlink(2) (rm), symlink(2) (ln -s), link(2) (ln),
and rename(2) (mv) are supported, subject to normal file and directory
permissions.
The following system calls are not supported in the /vol filesystem:
creat(2), only when creating a file, and mknod(2).
If the media does not contain file systems that can be automatically
mounted by rmmount(1M), users can gain access to the media through the
following /vol locations:
┌───────────────────────────────────┬────────────────────────────────────┐
│ Location │ State of Media │
├───────────────────────────────────┼────────────────────────────────────┤
│/vol/dev/diskette0/unnamed_floppy │ formatted unnamed floppy-block │
│ │ device access │
├───────────────────────────────────┼────────────────────────────────────┤
│/vol/dev/rdiskette0/unnamed_floppy │ formatted unnamed floppy-raw │
│ │ device access │
├───────────────────────────────────┼────────────────────────────────────┤
│/vol/dev/diskette0/unlabeled │ unlabeled floppy-block device │
│ │ access │
├───────────────────────────────────┼────────────────────────────────────┤
│/vol/dev/rdiskette0/unlabeled │ unlabeled floppy-raw device access │
├───────────────────────────────────┼────────────────────────────────────┤
│/vol/dev/dsk/c0t6/unnamed_cdrom │ CD-ROM-block device access │
├───────────────────────────────────┼────────────────────────────────────┤
│/vol/dev/rdsk/c0t6/unnamed_cdrom │ CD-ROM-raw device access │
└───────────────────────────────────┴────────────────────────────────────┘
For more information on the location of CD-ROM and floppy media, see
System Administration Guide: Basic Administration or rmmount(1M).
Partitions
Some media support the concept of a partition. If the label identifies
partitions on the media, the name of the media becomes a directory with
partitions under it. Only valid partitions are represented. Partitions
cannot be moved out of a directory.
For example, if disk volume 'foo' has three valid partitions, 0, 2, and
5, then:
/vol/dsk/foo/s0
/vol/dsk/foo/s2
/vol/dsk/foo/s5
for block access and
/vol/rdsk/foo/s0
/vol/rdsk/foo/s2
/vol/rdsk/foo/s5
for character access.
If a volume is relabeled to reflect different partitions, the name
space changes to reflect the new partition layout.
A format program can check to see if there are others with the volume
open and not allow the format to occur if it is. Volume Management,
however, does not explicitly prevent the rewriting of a label while
others have the volume open. If a partition of a volume is open, and
the volume is relabeled to remove that partition, it will appear
exactly as if the volume were missing. A notify event will be generated
and the user may cancel the operation with volcancel(1), if desired.
SEE ALSOvolcancel(1), volcheck(1), volmissing(1)rmmount(1M), vold(1M),
rmmount.conf(4), vold.conf(4)
System Administration Guide: Basic Administration
SunOS 5.10 30 Jan 2006 volfs(7FS)
