that use it. Specifically, vop_stdlock uses the lock pointed to by
vp->v_vnlock. By default, getnewvnode sets up vp->v_vnlock to
reference vp->v_lock. Filesystems that wish to use the default
do not need to allocate a lock at the front of their node structure
(as some still did) or do a lockinit. They can simply start using
vn_lock/VOP_UNLOCK. Filesystems that wish to manage their own locks,
but still use the vop_stdlock functions (such as nullfs) can simply
replace vp->v_vnlock with a pointer to the lock that they wish to
have used for the vnode. Such filesystems are responsible for
setting the vp->v_vnlock back to the default in their vop_reclaim
routine (e.g., vp->v_vnlock = &vp->v_lock).
In theory, this set of changes cleans up the existing filesystem
lock interface and should have no function change to the existing
locking scheme.
Sponsored by: DARPA & NAI Labs.
configuration. Root privileges override DAC on local file systems and
therefore root does not generally need to be a member of a group to
access files owned by that group. In the NFS case, require explicit
authorization for root to have these privileges.
Leave root in operator for dump/restore broadcast reasons; leave root
in wheel until discrepencies in the "no users in wheel means any user
can su" policy are resolved (possibly indefinitely).
with the exception of indirect function calls, are assumed to be
intra load module and thus that GP will be the same. This avoids
saving, setting and restoring GP for each function call and
reduces the kernel with ~320KB. There's obviously a performance
benefit as well.
Note that since we generally don't know if calls will be intra or
inter load module when we're compiling kernel modules, -mconstant-gp
cannot be used for modules.
Fix the "@gprel relocation against dynamic symbol xxx" linker error.
Variables defined in the link unit and small enough to be put in the
short data section will have a gp-relative access sequence (using the
@gprel relocation). It is invalid to have @gprel relocations in shared
libraries, because they are to be resolved by the static linker and
not the dynamic linker. The -fpic option will cause @ltoff relocations
for @gprel relocations, but the side-effects are untested (if any).
Instead, disable/eliminate the short data section to achieve the same.
middle of this header.
o Remove unneeded conditionals to hide SIG* in the POSIX case.
(C allows implementations to define additional SIG* constants.)
o Add comments about missing features.
o Move the location of the sigset_t typedef.
o Update standards visibility conditionals.
o Fix some assumptions about what pid_t and uid_t are defined as.
o Remove size_t typedef and use __size_t in struct sigaltstack
instead.
