Add rump.fssconfig

branches: 1.1.78;
The file system snapshot pseudo driver.

Uses a hook in spec_strategy() to save data written from a mounted
file system to its block device and a hook in dounmount().

Not enabled by default in any kernel config.

Approved by: Frank van der Linden <fvdl@netbsd.org>

Improve wording, enhance the example

branches: 1.11.8;
Describe the differences between file system internal and external snapshots.

Fix typo.

Fix wording: s/ffs file systems/FFS file systems/
Proposed by Snader_LB

branches: 1.8.2;
File system snapshots are no longer experimental.
Forgot to chang this man page in Nov 2011.

branches: 1.7.4; 1.7.22;
Convert TNF licenses to new 2 clause variant

branches: 1.6.24;
Give Dd the full month name as argument.

Note file system internal snapshots.

Add ffs internal snapshots. Written by Marshall Kirk McKusick for FreeBSD.

- Not enabled by default. Needs kernel option FFS_SNAPSHOT.
- Change parameters of ffs_blkfree.
- Let the copy-on-write functions return an error so spec_strategy
may fail if the copy-on-write fails.
- Change genfs_*lock*() to use vp->v_vnlock instead of &vp->v_lock.
- Add flag B_METAONLY to VOP_BALLOC to return indirect block buffer.
- Add a function ffs_checkfreefile needed for snapshot creation.
- Add special handling of snapshot files:
Snapshots may not be opened for writing and the attributes are read-only.
Use the mtime as the time this snapshot was taken.
Deny mtime updates for snapshot files.
- Add function transferlockers to transfer any waiting processes from
one lock to another.
- Add vfsop VFS_SNAPSHOT to take a snapshot and make it accessible through
a vnode.
- Add snapshot support to ls, fsck_ffs and dump.

Welcome to 2.0F.

Approved by: Jason R. Thorpe <thorpej@netbsd.org>

Update the file system snapshot driver:
- Document the kernel thread.
- Rename some functions and variables.
- Return EROFS where appropriate.
- Use shifts instead of 64-bit divide.
- Use a simple_lock to make it MP-safe.
- Add M_CANFAIL to malloc to avoid panic on large cluster size.
- Allow sparse file for backing store and use VOP_BALLOC() to allocate
space. Default size of backing store is the size of the file system.

Drop trailing spaces; new sentence, new line; fix width
argument to avoid confusion (indent is only magic for -offset); add a comma
for easier reading.

The file system snapshot pseudo driver.

Uses a hook in spec_strategy() to save data written from a mounted
file system to its block device and a hook in dounmount().

Not enabled by default in any kernel config.

Approved by: Frank van der Linden <fvdl@netbsd.org>

Use stat() information to decide if the backing store is a directory.
Depending on open() returning EISDIR fails for mount points.

branches: 1.12.6;
Add rump.fssconfig

Update command line parsing to match reality. Only one of -c, -u, or
-l can be specified, and the -x option is available only for -c.

branches: 1.10.12;
include the headers you need

branches: 1.9.2;
Initialize `fss_flags' before setting an individual bit.
Not a real problem as there is only one valid bit yet.

From Edgar Fuss via tech-kern@netbsd.org

branches: 1.8.2; 1.8.4;
static + __dead

fss(4): Allow FSSIOCSET to set the initial flags. Add a new flag
"FSS_UNLINK_ON_CREATE" to unlink the backing store before
the snapshot gets created.

With this change dump(8) no longer dumps the zero-sized, but named
snapshot it is working on. Same applies to fsck_ffs(8).

branches: 1.6.6; 1.6.18;
Remove clause 3 and 4 from TNF licenses

branches: 1.5.18;
Support user controllable flags for the snapshot driver:
- Add FSSIOFSET and FSSIOFGET ioctl() to set/get the flags.
- Add FSS_UNCONFIG_ON_CLOSE flag to unconfigure the snapshot device
on the last close.

Reviewed by: Jason R. Thorpe <thorpej@netbsd.org>

branches: 1.4.2;
Add ffs internal snapshots. Written by Marshall Kirk McKusick for FreeBSD.

- Not enabled by default. Needs kernel option FFS_SNAPSHOT.
- Change parameters of ffs_blkfree.
- Let the copy-on-write functions return an error so spec_strategy
may fail if the copy-on-write fails.
- Change genfs_*lock*() to use vp->v_vnlock instead of &vp->v_lock.
- Add flag B_METAONLY to VOP_BALLOC to return indirect block buffer.
- Add a function ffs_checkfreefile needed for snapshot creation.
- Add special handling of snapshot files:
Snapshots may not be opened for writing and the attributes are read-only.
Use the mtime as the time this snapshot was taken.
Deny mtime updates for snapshot files.
- Add function transferlockers to transfer any waiting processes from
one lock to another.
- Add vfsop VFS_SNAPSHOT to take a snapshot and make it accessible through
a vnode.
- Add snapshot support to ls, fsck_ffs and dump.

Welcome to 2.0F.

Approved by: Jason R. Thorpe <thorpej@netbsd.org>

Replace the statfs() family of system calls with statvfs().
Retain binary compatibility.

Update the file system snapshot driver:
- Document the kernel thread.
- Rename some functions and variables.
- Return EROFS where appropriate.
- Use shifts instead of 64-bit divide.
- Use a simple_lock to make it MP-safe.
- Add M_CANFAIL to malloc to avoid panic on large cluster size.
- Allow sparse file for backing store and use VOP_BALLOC() to allocate
space. Default size of backing store is the size of the file system.

The file system snapshot pseudo driver.

Uses a hook in spec_strategy() to save data written from a mounted
file system to its block device and a hook in dounmount().

Not enabled by default in any kernel config.

Approved by: Frank van der Linden <fvdl@netbsd.org>

Include rump-vs-host ops files

branches: 1.1.2;
file fssconfig_hostops.c was initially added on branch pgoyette-localcount.

Include rump-vs-host ops files

branches: 1.1.2;
file fssconfig_rumpops.c was initially added on branch pgoyette-localcount.

Include rump-vs-host ops files

branches: 1.1.2;
file prog_ops.h was initially added on branch pgoyette-localcount.