Seigo Tanimura (tanimura) posted the initial delta.
I've polished it quite a bit reducing the need for locking and
adapting it for KSE.
Locks:
1 mutex in each filedesc
protects all the fields.
protects "struct file" initialization, while a struct file
is being changed from &badfileops -> &pipeops or something
the filedesc should be locked.
1 mutex in each struct file
protects the refcount fields.
doesn't protect anything else.
the flags used for garbage collection have been moved to
f_gcflag which was the FILLER short, this doesn't need
locking because the garbage collection is a single threaded
container.
could likely be made to use a pool mutex.
1 sx lock for the global filelist.
struct file * fhold(struct file *fp);
/* increments reference count on a file */
struct file * fhold_locked(struct file *fp);
/* like fhold but expects file to locked */
struct file * ffind_hold(struct thread *, int fd);
/* finds the struct file in thread, adds one reference and
returns it unlocked */
struct file * ffind_lock(struct thread *, int fd);
/* ffind_hold, but returns file locked */
I still have to smp-safe the fget cruft, I'll get to that asap.
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.
Sorry john! (your next MFC will be a doosie!)
Reviewed by: peter@freebsd.org, dillon@freebsd.org
X-MFC after: ha ha ha ha
systems were repo-copied from sys/miscfs to sys/fs.
- Renamed the following file systems and their modules:
fdesc -> fdescfs, portal -> portalfs, union -> unionfs.
- Renamed corresponding kernel options:
FDESC -> FDESCFS, PORTAL -> PORTALFS, UNION -> UNIONFS.
- Install header files for the above file systems.
- Removed bogus -I${.CURDIR}/../../sys CFLAGS from userland
Makefiles.
other "system" header files.
Also help the deprecation of lockmgr.h by making it a sub-include of
sys/lock.h and removing sys/lockmgr.h form kernel .c files.
Sort sys/*.h includes where possible in affected files.
OK'ed by: bde (with reservations)
Make 7 filesystems which don't really know about VOP_BMAP rely
on the default vector, rather than more or less complete local
vop_nopbmap() implementations.
file types to requiring all file types to properly implement fo_stat.
This makes any new file type additions much easier as this code no
longer has to be modified to accomodate it.
o Instead of using curproc in fdesc_allocvp, pass a `struct proc' pointer as
a new fifth parameter.
the gating of system calls that cause modifications to the underlying
filesystem. The gating can be enabled by any filesystem that needs
to consistently suspend operations by adding the vop_stdgetwritemount
to their set of vnops. Once gating is enabled, the function
vfs_write_suspend stops all new write operations to a filesystem,
allows any filesystem modifying system calls already in progress
to complete, then sync's the filesystem to disk and returns. The
function vfs_write_resume allows the suspended write operations to
begin again. Gating is not added by default for all filesystems as
for SMP systems it adds two extra locks to such critical kernel
paths as the write system call. Thus, gating should only be added
as needed.
Details on the use and current status of snapshots in FFS can be
found in /sys/ufs/ffs/README.snapshot so for brevity and timelyness
is not included here. Unless and until you create a snapshot file,
these changes should have no effect on your system (famous last words).
Don't fake any file types, just set vap->va_type to IFTOVT(stb.st_mode).
If something does not report its mode, vap->va_type is set to VNON
accordingly.
problems when fetch(1) was passed `-o -'. The rationale of this change
is that applications attempting to change underlying vnodes for /dev/fd
nodes are improperly written and the use of this interface should not
ever have been encouraged. Proper alternatives are fchmod, fchown and
others.
PR: 18952
- Remove stale, unused fdescnode->fd_link structure member.
stderr nodes. More specific items of this patch:
o Removed support for symbolic links, and the need for
fdesc_readlink().
o Put all the code from fdesc_attr() into fdesc_getattr() and removed
fdesc_attr(). This also made it easier to properly give all nodes
unique inode numbers.
o The removal of all non-fd nodes allowed the removal of the fdesc_read(),
fdesc_write(), and fdesc_ioctl() nodes, since we no longer have nodes
that get special handling.
o Correct the component name validity-checking in fdesc_lookup(). It
previously detected the end of the string by checking for a terminating
NUL, now it uses cnp->cn_namelen.
o Handle kqueue files as FIFOs. This is probably the closest file type
to represent this type of file there is, and it is unfortunately not
very representative of a kqueue. Creation time is not supported by
kqueue, so ctime, mtime and atime are all set to the current time when
getattr() was called.
o Also set st_[mca]time to the current time since there's no data in
socket structures that can be used to fill this in (FIFOs).
o Simplify fdesc_readdir() since it only has to report the numbered
fd nodes. Add `.' and `..' directory links as well.
o Remove read bits from directories as they tend to confuse programs
like tar(1).
Reviewed by: phk
Discussed with: bde (earlier on, not quite review)
The cdevsw_add() function now finds the major number(s) in the
struct cdevsw passed to it. cdevsw_add_generic() is no longer
needed, cdevsw_add() does the same thing.
cdevsw_add() will print an message if the d_maj field looks bogus.
Remove nblkdev and nchrdev variables. Most places they were used
bogusly. Instead check a dev_t for validity by seeing if devsw()
or bdevsw() returns NULL.
Move bdevsw() and devsw() functions to kern/kern_conf.c
Bump __FreeBSD_version to 400006
This commit removes:
72 bogus makedev() calls
26 bogus SYSINIT functions
if_xe.c bogusly accessed cdevsw[], author/maintainer please fix.
I4b and vinum not changed. Patches emailed to authors. LINT
probably broken until they catch up.
and missing arg checking.
Panic instead of returning bogus error codes or forgetting to check
all cases if fdesc_readdir() gets called for a non-directory. This
can't happen.
Rename vn_default_error to vop_defaultop all over the place.
Move vn_bwrite from vfs_bio.c to vfs_default.c and call it vop_stdbwrite.
Use vop_null instead of nullop.
Move vop_nopoll from vfs_subr.c to vfs_default.c
Move vop_sharedlock from vfs_subr.c to vfs_default.c
Move vop_nolock from vfs_subr.c to vfs_default.c
Move vop_nounlock from vfs_subr.c to vfs_default.c
Move vop_noislocked from vfs_subr.c to vfs_default.c
Use vop_ebadf instead of *_ebadf.
Add vop_defaultop for getpages on master vnode in MFS.
1. Add defaults for more VOPs
VOP_LOCK vop_nolock
VOP_ISLOCKED vop_noislocked
VOP_UNLOCK vop_nounlock
and remove direct reference in filesystems.
2. Rename the nfsv2 vnop tables to improve sorting order.
1. Remove VOP_UPDATE, it is (also) an UFS/{FFS,LFS,EXT2FS,MFS}
intereface function, and now lives in the ufsmount structure.
2. Remove VOP_SEEK, it was unused.
3. Add mode default vops:
VOP_ADVLOCK vop_einval
VOP_CLOSE vop_null
VOP_FSYNC vop_null
VOP_IOCTL vop_enotty
VOP_MMAP vop_einval
VOP_OPEN vop_null
VOP_PATHCONF vop_einval
VOP_READLINK vop_einval
VOP_REALLOCBLKS vop_eopnotsupp
And remove identical functionality from filesystems
4. Add vop_stdpathconf, which returns the canonical stuff. Use
it in the filesystems. (XXX: It's probably wrong that specfs
and fifofs sets this vop, shouldn't it come from the "host"
filesystem, for instance ufs or cd9660 ?)
5. Try to make system wide VOP functions have vop_* names.
6. Initialize the um_* vectors in LFS.
(Recompile your LKMS!!!)
1. Add new file "sys/kern/vfs_default.c" where default actions for
VOPs go. Implement proper defaults for ABORTOP, BWRITE, LEASE,
POLL, REVOKE and STRATEGY. Various stuff spread over the entire
tree belongs here.
2. Change VOP_BLKATOFF to a normal function in cd9660.
3. Kill VOP_BLKATOFF, VOP_TRUNCATE, VOP_VFREE, VOP_VALLOC. These
are private interface functions between UFS and the underlying
storage manager layer (FFS/LFS/MFS/EXT2FS). The functions now
live in struct ufsmount instead.
4. Remove a kludge of VOP_ functions in all filesystems, that did
nothing but obscure the simplicity and break the expandability.
If a filesystem doesn't implement VOP_FOO, it shouldn't have an
entry for it in its vnops table. The system will try to DTRT
if it is not implemented. There are still some cruft left, but
the bulk of it is done.
5. Fix another VCALL in vfs_cache.c (thanks Bruce!)
1. Remove comment stating the blatantly obvious.
2. Align in two columns.
3. Sort all but the default element alphabetically.
4. Remove XXX comments pointing out entries not needed.
