CVS commit: src/sys

[Andrew Doran <ad%netbsd.org@localhost>]

Module Name:    src
Committed By:   ad
Date:           Tue Apr 29 23:51:05 UTC 2008

Modified Files:
        src/sys/coda: coda_psdev.c
        src/sys/compat/common: vfs_syscalls_20.c
        src/sys/fs/puffs: puffs_msgif.c
        src/sys/fs/union: union_vnops.c
        src/sys/kern: vfs_lookup.c vfs_subr.c vfs_subr2.c vfs_syscalls.c
        src/sys/miscfs/procfs: procfs_linux.c
        src/sys/miscfs/syncfs: sync_vnops.c
        src/sys/nfs: nfs_export.c
        src/sys/sys: mount.h
        src/sys/ufs/lfs: lfs_bio.c lfs_vfsops.c
        src/sys/ufs/mfs: mfs_vfsops.c

Log Message:
kern/38135 vfs_busy/vfs_trybusy confusion

The symptom was that sometimes file systems would occasionally not appear
in output from 'df' or 'mount' if the system was busy. Resolution:

- Make mount locks work somewhat like vm_map locks.
- vfs_trybusy() now only fails if the mount is gone, or if someone is
  unmounting the file system. Simple contention on mnt_lock doesn't
  cause it to fail.
- vfs_busy() will wait even if the file system is being unmounted.


To generate a diff of this commit:
cvs rdiff -r1.43 -r1.44 src/sys/coda/coda_psdev.c
cvs rdiff -r1.26 -r1.27 src/sys/compat/common/vfs_syscalls_20.c
cvs rdiff -r1.68 -r1.69 src/sys/fs/puffs/puffs_msgif.c
cvs rdiff -r1.30 -r1.31 src/sys/fs/union/union_vnops.c
cvs rdiff -r1.104 -r1.105 src/sys/kern/vfs_lookup.c
cvs rdiff -r1.337 -r1.338 src/sys/kern/vfs_subr.c
cvs rdiff -r1.20 -r1.21 src/sys/kern/vfs_subr2.c
cvs rdiff -r1.352 -r1.353 src/sys/kern/vfs_syscalls.c
cvs rdiff -r1.50 -r1.51 src/sys/miscfs/procfs/procfs_linux.c
cvs rdiff -r1.22 -r1.23 src/sys/miscfs/syncfs/sync_vnops.c
cvs rdiff -r1.34 -r1.35 src/sys/nfs/nfs_export.c
cvs rdiff -r1.174 -r1.175 src/sys/sys/mount.h
cvs rdiff -r1.111 -r1.112 src/sys/ufs/lfs/lfs_bio.c
cvs rdiff -r1.257 -r1.258 src/sys/ufs/lfs/lfs_vfsops.c
cvs rdiff -r1.93 -r1.94 src/sys/ufs/mfs/mfs_vfsops.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.