a simple attempt instead of an authoritative answer. The failure of the
rootspec test could me machine-dependant. Thanks to martin@ for pointing
that out.
iterator and the length of the old child array, but introduce a
new variable, 'olen', for the latter purpose.
In sysctl_alloc(), name a constant.
Introduce sysctl_log_print(), a handy debug routine.
No functional changes intended.
yet in service, have a correct pointer to their parent, sysctl_parent.
This fixes a bug where sysctl_teardown(9) could not clean up a
network interface's sysctl(9) trees when I detached it, because
the wrong log had been recorded.
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!
and vtime > 0. It should be allowed to go to sleep for the sleep interval
indicated in vtime. Reported by der Mouse a long while ago, and this is what
other unixes do.
Factor out common code of chroot-like syscalls into change_root() and export
that function for use in other parts of the kernel.
Rename change_dir() to chdir_lookup() as the latter describes better what
the function does. While there, move the namei_data initialisation into
chdir_lookup(), too. And export chdir_lookup().
mq_prio_max is dynamic, and sorted list is used for custom setup, when
user manually sets higher priority range.
- Cache mq->mq_attrib in some places. Change msg_ptr type to uint8_t.
- Update copyright, misc.
taking a reference to curlwp's by calling fd_hold(). If lwp_create()
is called from fork1(), then l2 != curlwp, but l2's and not curlwp's
filedesc_t whose reference we should take.
This change stops the problem I describe in
<http://mail-index.netbsd.org/tech-kern/2009/07/09/msg005422.html>,
where /dev/rsd0a is never properly closed after fsck / runs on it.
This change seems to quiet my USB backup drive, sd0 at scsibus0 at
umass0, which had stopped spinning down when it was not in use:
The unit probably stayed open after mount(8) tried (and failed:
errant fstab entry) to mount it.
I am confident that this change is an improvement, but I doubt that
it is the last word on the matter. I hate to get under the filedesc_t
abstraction by fiddling with fd_refcnt, and there may be something
I have missed, so somebody with greater understanding of the file
descriptors code should have a look.
must not allocate a pmf_event_workitem_t using kmem_alloc(9). Use
pool_cache(9), instead, because it is safe in interrupt context.
Thanks, rmind@, for catching the problem and suggesting the solution.
latter might lose its KAUTH_GENERIC_ISSUSER check soon, add an internal
function, mqueue_access(), and call genfs_can_access() from it instead
so we don't pollute the main code path once we need to add a special
kauth(9) check for message queues.
No functional change, error codes preserved.
Related mailing list thread:
http://mail-index.netbsd.org/tech-kern/2009/06/21/msg005311.html
check_console, veriexecclose, veriexec_delete, veriexec_file_add,
emul_find_root, coff_load_shlib (sh3 version), coff_load_shlib,
compat_20_sys_statfs, compat_20_netbsd32_statfs,
ELFNAME2(netbsd32,probe_noteless), darwin_sys_statfs,
ibcs2_sys_statfs, ibcs2_sys_statvfs, linux_sys_uselib,
osf1_sys_statfs, sunos_sys_statfs, sunos32_sys_statfs,
ultrix_sys_statfs, do_sys_mount, fss_create_files (3 of 4),
adosfs_mount, cd9660_mount, coda_ioctl, coda_mount, ext2fs_mount,
ffs_mount, filecore_mount, hfs_mount, lfs_mount, msdosfs_mount,
ntfs_mount, sysvbfs_mount, udf_mount, union_mount, sys_chflags,
sys_lchflags, sys_chmod, sys_lchmod, sys_chown, sys_lchown,
sys___posix_chown, sys___posix_lchown, sys_link, do_sys_pstatvfs,
sys_quotactl, sys_revoke, sys_truncate, do_sys_utimes, sys_extattrctl,
sys_extattr_set_file, sys_extattr_set_link, sys_extattr_get_file,
sys_extattr_get_link, sys_extattr_delete_file,
sys_extattr_delete_link, sys_extattr_list_file, sys_extattr_list_link,
sys_setxattr, sys_lsetxattr, sys_getxattr, sys_lgetxattr,
sys_listxattr, sys_llistxattr, sys_removexattr, sys_lremovexattr
All have been scrutinized (several times, in fact) and compile-tested,
but not all have been explicitly tested in action.
XXX: While I haven't (intentionally) changed the use or nonuse of
XXX: TRYEMULROOT in any of these places, I'm not convinced all the
XXX: uses are correct; an audit might be desirable.
case functionality of namei in a simple package with only a couple flags.
A substantial majority of the namei call sites in the kernel can use
this interface; this will isolate those areas from the changes arising
as the internals of namei are fumigated.
activity of other threads will perform the TLB flush for the processes using
emap as a side effect. To track that, global and per-CPU generation numbers
are used. This idea was suggested by Andrew Doran; various improvements to
it by me. Notes:
- For now, zero-copy on pipe is not yet enabled.
- TCP socket code would likely need more work.
- Additional UVM loaning improvements are needed.
Proposed on <tech-kern>, silence there.
Quickly reviewed by <ad>.
(void *)pew is one way to get a struct work *, but let's
write&pew->pew_work, instead. It is more defensive and persuasive.
Make miscellaneous changes in support of tearing down arbitrary
stacks of filesystems and devices during shutdown:
1 Move struct shutdown_state, shutdown_first(), and shutdown_next(),
from kern_pmf.c to subr_autoconf.c. Rename detach_all() to
config_detach_all(), and move it from kern_pmf.c to subr_autoconf.c.
Export all of those routines.
2 In pmf_system_shutdown(), do not suspend user process scheduling, and
do not detach all devices: I am going to do that in cpu_reboot(),
instead. (Soon I will do it in an MI cpu_reboot() routine.) Do still
call PMF shutdown hooks.
3 In config_detach(), add a DIAGNOSTIC assertion: if we're exiting
config_detach() at the bottom, alldevs_nwrite had better not be 0,
because config_detach() is a writer of the device list.
4 In deviter_release(), check to see if we're iterating the device list
for reading, *first*, and if so, decrease the number of readers. Used
to be that if we happened to be reading during shutdown, we ran the
shutdown branch. Thus the number of writers reached 0, the number
of readers remained > 0, and no writer could iterate again. Under
certain circumstances that would cause a hang during shutdown.
filesystem is mounted. Synchronize access to the number with a
mutex. When a struct mount, mp, is allocated, assign the current
generation number to mp->mnt_gen. Introduce vfs_unmount_forceone()
that forcefully unmounts the most recently mounted filesystem.
Refactor: extract vfs_shutdown1() from vfs_shutdown(). Extract
vfs_sync_all() from vfs_shutdown1().
Print more progress indications while we're unmounting all of the
filesystems during shutdown.
We increase the reference count on mp before calling dounmount(mp),
but we do not decrease it if dounmount(mp) fails, and neither does
dounmount(mp). So decrease the reference count if dounmount(mp)
fails.
Change the loop terminating condition in vfs_unmountall1() to (mp
!= (void *)&mountlist) from !CIRCLEQ_EMPTY(&mountlist), because we
may not ever empty the list, especially if we're not forcing the
filesystems to unmount.
the other routines of the same spirit.
Adjust file-system code to use it.
Keep vaccess() for KPI compatibility and to keep element of least
surprise. A "diagnostic" message warning that vaccess() is deprecated will
be printed when it's used (obviously, only in DIAGNOSTIC kernels).
No objections on tech-kern@:
http://mail-index.netbsd.org/tech-kern/2009/06/21/msg005310.html
by making the pps count time stamp and the update
time stamp u_int64.
The time delta between two PPS events can now
be correctly calculated avoiding any unaccounted
for wraps with 32-bit counters.
When I originally wrote this, I was going for maximum flexibility.
However, after a private discussion with dholland@, I see how this
will cause problems with the future world order of namei whenever
that might be. At the moment, I don't need the extra flexibility,
but if something comes up this may have to be revisited.
mq_send() should fail due to permissions. Noted by Stathis Kamperis!
- Check for empty message queue name (POSIX does not allow this for regular
files, and it's weird), check for DTYPE_MQUEUE, fix permission check in
mq_unlink(), clean up.
these commits move all path handling into module_do_load() from
kobj_load_file(). This way the final path used to load a module
is available for loading <module>.plist, which will store parameters
for a module. The end goal of this project is good support for
MODULAR device drivers.
- Avoid atomics in more places.
- Remove the per-descriptor mutex, and just use filedesc_t::fd_lock.
It was only being used to synchronize close, and in any case we needed
to take fd_lock to free the descriptor slot.
- Optimize certain paths for the <NDFDFILE case.
- Sprinkle more comments and assertions.
- Cache more stuff in filedesc_t.
- Fix numerous minor bugs spotted along the way.
- Restructure how the open files array is maintained, for clarity and so
that we can eliminate the membar_consumer() call in fd_getfile(). This is
mostly syntactic sugar; the main functional change is that fd_nfiles now
lives alongside the open file array.
Some measurements with libmicro:
- simple file syscalls are like close() are between 1 to 10% faster.
- some nice improvements, e.g. poll(1000) which is ~50% faster.
- Fix a preemption bug in CURCPU_IDLE_P() that can lead to a bogus
assertion failure on DEBUG kernels.
- Fix MP/preemption races with timecounter detachment.
- Fix a preemption bug in CURCPU_IDLE_P() that can lead to a bogus
assertion failure on DEBUG kernels.
- Fix MP/preemption races with timecounter detachment.
this fixes the following deadlock.
a thread doing getcleanvnode:
pick a vnode
acqure v_interlock
v_usecount++
call vclean
now, another thread doing cache_lookup:
picks the vnode
vtryget succeed
vn_lock succeed
now in vclean:
set VI_XLOCK (too late to be noticed by the competing thread)
wait on the vnode lock (this might violate locking order)
the use of a flag bit was suggested by Andrew Doran. PR/41374.
Without it, on ports where splhigh() is inline, the compiler will optimise
the second SOFTINT_PENDING test in softint_schedule(). A dissasembly
of softint_schedule() with and without the volatile sh_flags confirm this
on sparc.
Because of this there is a race that could lead to the softhand_t
being enqueued twice on si_q, leading to a corrupted queue and
some handler being SOFTINT_PENDING but never called.
Should fix PR kern/38637
way they can be included without having to include DDB.
(arguably all print routines should be behind #ifdef DEBUGPRINT
and options DDB should define that macro, but I'll tackle that later)
a new struct mount-allocation routine, vfs_mountalloc(9). Documentation
updates will follow.
Attention: Synchronization Oversight Committee! In mount_domount(),
I postpone the call mutex_enter(&mp->mnt_updating) until right before
the VFS_MOUNT(9) call because (1) that looks to me like the earliest
possible opportunity for mp to become visible to any other LWP, because
it was just kmem_zalloc(9)'d and (2) it made extracting the common code
much easier. Tell me if my reasoning is faulty.
proc_enterpgrp() with proc_leavepgrp() to free process group and/or
session without proc_lock held.
- Rename SESSHOLD() and SESSRELE() to to proc_sesshold() and
proc_sessrele(). The later releases proc_lock now.
Quick OK by <ad>.
sometimes do not serve as memory barriers, allowing memory references to
bleed outside of critical sections. It's possible that this is the
reason for pkgbuild's longstanding crashiness.
For rwlocks, always enable the explicit membars. They were disabled only
on x86, and since they are not in the fast-path it's not a big deal.
TODO: convert these to an atomic_membar_foo() or similar that does ordering
between regular data references and atomic references.
- Add interrupt shielding (direct hardware interrupts away from the
specified CPUs). Not documented just yet but will be soon.
- Redo /dev/cpu time_t compat so no kernel changes are needed.
x86:
- Make intr_establish, intr_disestablish safe to use when !cold.
- Distribute hardware interrupts among the CPUs, instead of directing
everything to the boot CPU.
- Add MD code for interrupt sheilding. This works in most cases but there is
a bug where delivery is not accepted by an LAPIC after redistribution. It
also needs re-balancing to make things fair after interrupts are turned
back on for a CPU.
over and over to detach all of the devices. Stop when we cannot detach
even a single device in a cycle. Call shutdown hooks on all of the
devices that remain attached.
This is another step toward the detach/unmount cycle that will help us
tear down arbitrary stacks of filesystems, ccd(4), raid(4), and vnd(4).
filesystem at all, false otherwise. This will support tearing down
stacks of filesystems, ccd(4), raid(4), and vnd(4).
Change the misleading variable name 'allerror' to 'any_error'. Make it
a bool.
manu