support -ve lengths (lock area before current offset).
Nothing in libc or the kernel allowed for this, so some random part
of the file would get locked (no idea which bits).
Although this could probably be fixed in libc, the stubs for posix file
locks for emulations could easily get into the kernel with -ve lengths.
So fixing in the kernel avoids those problems.
This also fixes PR/41620 (attempting to lock negative offsets) - which
is what I was looking into!
Re-init the condvar after memcpy'ing so that the TAILQ is valid.
regress/sys/kern/lockf now completes rather than failing in cv_wait_sig
with KASSERT(cv_has_waiters()).
we no longer need to guard against access from hardware interrupt handlers.
Additionally, if cloning a process with CLONE_SIGHAND, arrange to have the
child process share the parent's lock so that signal state may be kept in
sync. Partially addresses PR kern/37437.
This make uid_find(), chgproccnt(), chgsbsize() and lf_alloc(), lf_free()
functions lock-less.
- Increase the size of uihashtbl in case of MP system, as suggested by <ad>.
- Add HASH_SLIST type for hashinit().
Reviewed by <ad>.
chgsbsize() as mentioned in the PR can be called from an interrupt context
via tcp_close(). Avoid calling uid_find() in chgsbsize().
- Instead of storing so_uid in struct socketvar, store *so_uidinfo
- Add a simple lock to struct uidinfo.
to pool_init. Untouched pools are ones that either in arch-specific
code, or aren't initialiased during initial system startup.
Convert struct session, ucred and lockf to pools.
We cannot store LWP pointers permanently in lock structures, for two reasons:
1) They are somewhat ephemeral. Dangling pointers are bad.
2) A different LWP may issue the unlock, and in this case, we were not actually
doing the unlock at all. This was causing processes to exit without undoing
fcntl(2) locks. Furthermore, the locks are process-specific to begin with,
so the test was just plain wrong.
Instead, we go back to storing a proc pointer for POSIX locks. In addition, we
add an extra pointer to the LWP, which is used in deadlock detection. After
the lock is granted, this pointer is 0ed and there is no reference to the LWP.
Now evolution can inc my mail again.
