Commit Graph

4 Commits

Author SHA1 Message Date
hannken 8c21bc6224 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>
2004-05-25 14:54:55 +00:00
hannken 067a3b897d 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.
2004-01-11 19:05:26 +00:00
wiz 68c32a13a8 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.
2003-12-11 17:12:11 +00:00
hannken fbae381aaa 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>
2003-12-10 11:40:11 +00:00