(there are still some details to work out) but expect that to go
away soon. To support these basic changes (creation of lfs_putpages,
lfs_gop_write, mods to lfs_balloc) several other changes were made, to
wit:
* Create a writer daemon kernel thread whose purpose is to handle page
writes for the pagedaemon, but which also takes over some of the
functions of lfs_check(). This thread is started the first time an
LFS is mounted.
* Add a "flags" parameter to GOP_SIZE. Current values are
GOP_SIZE_READ, meaning that the call should return the size of the
in-core version of the file, and GOP_SIZE_WRITE, meaning that it
should return the on-disk size. One of GOP_SIZE_READ or
GOP_SIZE_WRITE must be specified.
* Instead of using malloc(...M_WAITOK) for everything, reserve enough
resources to get by and use malloc(...M_NOWAIT), using the reserves if
necessary. Use the pool subsystem for structures small enough that
this is feasible. This also obsoletes LFS_THROTTLE.
And a few that are not strictly necessary:
* Moves the LFS inode extensions off onto a separately allocated
structure; getting closer to LFS as an LKM. "Welcome to 1.6O."
* Unified GOP_ALLOC between FFS and LFS.
* Update LFS copyright headers to correct values.
* Actually cast to unsigned in lfs_shellsort, like the comment says.
* Keep track of which segments were empty before the previous
checkpoint; any segments that pass two checkpoints both dirty and
empty can be summarily cleaned. Do this. Right now lfs_segclean
still works, but this should be turned into an effectless
compatibility syscall.
malloc types into a structure, a pointer to which is passed around,
instead of an int constant. Allow the limit to be adjusted when the
malloc type is defined, or with a function call, as suggested by
Jonathan Stone.
(backout parts of rev.1.40)
otherwise, directory structures can be corrupted because checkpoints can
occur via eg. lfs_vflush before parent directory is written.
- move calls to softdep_setup_pagecache() (which can sleep to allocate
memory) outside the softdep lock.
- replace the softdep_flush_indir() hack (which tries to find another
vnode to fsync when we are holding lots of buffer-cache buffers locked
for long periods of time) with softdep_trackbufs() (which just kicks
the syncer and sleeps under the same circumstances). the former method
had a lock-ordering problem which would occasionally deadlock.
- relax the assertion in softdep_sync_metadata() which says that we should
never see D_ALLOCDIRECT deps for VREG vnodes. it's ok to see those
attached to indirect blocks.
also, there's no need to splbio() while allocating the buffer headers
to which pagecache dependencies are attached, so remove that.
fixes all the problems in PR 19288.
(backout rev.1.74)
it seems that there's no need to do it (anymore?) and LFS has trouble with it.
(VNON vnodes marked VDIROP will never reclaimed)
ok'ed by Frank van der Linden.
try to reclaim them.
(workaround for deadlock noted in the comment in lfs_reserveavail)
- in lfs_rename, mark vnodes which are being moved as well as directry vnodes.
- don't wait for locking buf in lfs_bwrite_ext to avoid deadlocks.
- skip lfs_reserve when we're doing dirop.
reserve more (for lfs_truncate) in set_dirop instead.
this mostly solves PR 18972. (and hopefully PR 19196)
mark inode IN_CLEANING rather then IN_MODIFIED.
otherwise cleaned (indirect) blocks belongs to the inode isn't written
until next sync.
- add assertions.
