Commit Graph

10929 Commits

Author SHA1 Message Date
John Baldwin
910826246c Tweak the wording for vfs_mark_atime() since the I/O it is avoiding by not
updating va_atime via VOP_SETATTR() isn't always synchronous.  For some
filesystems it is asynchronous.

Suggested by:  bde
2009-01-23 22:13:00 +00:00
John Baldwin
645f1f4ea3 Push down Giant in the vlnru kproc main loop so that it is only acquired
around calls to vlrureclaim() on non-MPSAFE filesystems.  Specifically,
vnlru no longer needs Giant for the common case of waking up and deciding
there is nothing for it to do.

MFC after:	2 weeks
2009-01-23 22:08:54 +00:00
John Baldwin
e588eeb1dc Use the correct type for the timeout parameter to the 32-bit
compat version aio_waitcomplete().

Reminded by:	bz
Submitted by:	jamie
MFC after:	3 days
2009-01-23 13:23:17 +00:00
John Baldwin
1c570a0c09 Fix a few style bogons.
Submitted by:	bde
2009-01-21 20:08:17 +00:00
Konstantin Belousov
e9aff35739 Move the code from ufs_lookup.c used to do dotdot lookup, into
the helper function. It is supposed to be useful for any filesystem
that has to unlock dvp to walk to the ".." entry in lookup routine.

Requested by:	jhb
Tested by:	pho
MFC after:	1 month
2009-01-21 14:51:38 +00:00
John Baldwin
beace17649 Move the VA_MARKATIME flag for VOP_SETATTR() out into its own VOP:
VOP_MARKATIME() since unlike the rest of VOP_SETATTR(), VA_MARKATIME
can be performed while holding a shared vnode lock (the same functionality
is done internally by VOP_READ which can run with a shared vnode lock).
Add missing locking of the vnode interlock to the ufs implementation and
remove a special note and test from the NFS client about not supporting the
feature.

Inspired by:	ups
Tested by:	pho
2009-01-21 14:42:00 +00:00
Andrew Thompson
018cecb61b Add functions WITNESS so it can be asserted that the lock is not released for a
section of code, this uses WITNESS_NORELEASE() and WITNESS_RELEASEOK() to mark
the boundaries. Both functions require the lock to be held when calling.

This is intended for scenarios like a bus asserting that the bus lock is not
dropped during a driver call. There doesn't appear to be a man page to
document this in.

Reviewed by:	jhb
2009-01-21 04:19:18 +00:00
Konstantin Belousov
9316467d05 FFS puts the extended attributes blocks at the negative blocks for the
vnode, from -1 down. When vinvalbuf(vp, V_ALT) is done for the vnode, it
incorrectly does vm_object_page_remove(0, 0), removing all pages from
the underlying vm object, not only the pages that back the extended
attributes data.

Change vinvalbuf() to not remove any pages from the object when
V_NORMAL or V_ALT are specified. Instead, the only in-tree caller
in ffs_inode.c:ffs_truncate() that specifies V_ALT explicitely
removes the corresponding page range. The V_NORMAL caller
does vnode_pager_setsize(vp, 0) immediately after the call to
vinvalbuf(V_NORMAL) already.

Reported by:	csjp
Reviewed by:	ups
MFC after:	3 weeks
2009-01-20 11:27:45 +00:00
Stephen McKay
58c1607e03 Add a limit on namecache entries.
In normal operation, the number of cache entries is roughly equal to the
number of active vnodes.  However, when most of the recently accessed
vnodes have many hard links, the number of cache entries can be 32000
times as large, exhausting kernel memory and provoking a panic in
kmem_malloc().

MFC after: 2 weeks
2009-01-20 04:21:21 +00:00
Alexander Motin
129c5c814d Teach m_copyback() to use trailing space of the last mbuf in chain. 2009-01-18 20:19:55 +00:00
Jeff Roberson
8f51ad55e7 - Implement generic macros for producing KTR records that are compatible
with src/tools/sched/schedgraph.py.  This allows developers to quickly
   create a graphical view of ktr data for any resource in the system.
 - Add sched_tdname() and the pcpu field 'name' for quickly and uniformly
   identifying records associated with a thread or cpu.
 - Reimplement the KTR_SCHED traces using the new generic facility.

Obtained from:	attilio
Discussed with:	jhb
Sponsored by:	Nokia
2009-01-17 07:17:57 +00:00
Konstantin Belousov
137cf3b682 Lock the semaphore identifier lock during semaphore initialization to
guarantee atomicity of the operation for other semaphore consumers.
In particular, this should guard against access to the semaphore with
not done or partially done MAC label assignment.

Reviewed by:	rwatson
MFC after:	1 month
2009-01-15 12:15:46 +00:00
Konstantin Belousov
90a017ba64 It seems that there are at least three issues with IPC_RMID operation
on SysV semaphores.

  The squeeze of the semaphore array in the kern_semctl() modifies
  sem_base for the semaphores with sem_base greater then sem_base of
  the removed semaphore, as well as the values of the semaphores,
  without locking their mutex. This can lead to (killable) hangs or
  unexpected behaviour of the processes performing any sem operations
  while other process does IPC_RMID.

  The semexit_myhook() eventhandler unlocks SEMUNDO_LOCK() while
  accessing *suptr. This allows for IPC_RMID for the sem id to be
  performed in parallel with undo hook referenced by the current undo
  structure. This leads to the panic("semexit - semid not allocated") [1].

  The semaphore creation is protected by Giant, while IPC_RMID is done
  while only semaphore mutex is held. This seems to result in invalid
  values for semtot, causing random ENOSPC error returns [2].

Redo the locking of the semaphores lifetime cycle. Delegate the
sem_mtx to the sole purpose of protecting semget() and
semctl(IPC_RMID). Introduce new sem_undo_mtx to protect SEM_UNDO
handling. Remove the Giant remnants from the code.
Note that  mac_sysvsem_check_semget() and mac_sysvsem_create() are
now called while sem_mtx is held, as well as mac_sysvsem_cleanup() [3].

When semaphore is removed, acquire semaphore locks for all semaphores
with sem_base that is going to be changed by squeeze of the sema
array. The lock order is not important there, because the region is
protected by sem_mtx.

Organize both used and free sem_undo structures into the lists,
protected by sem_undo_mtx. In semexit_myhook(), remove sem_undo
structure that is being processed, from used list, without putting it
onto the free to prevent modifications by other threads. This allows
for sem_undo_lock to be dropped to acquire individial semaphore locks
without violating lock order. Since IPC_RMID may no longer find this
sem_undo, do tolerate references to unallocated semaphores in undo
structure, and check sequential number to not undo unrelated semaphore
with the same id.

While there, convert functions definitions to ANSI C and fix small
style(9) glitches.

Reported by:	Omer Faruk Sen <omerfsen gmail com> [1], pho [2]
Reviewed by:	rwatson [3]
Tested by:	pho
MFC after:	1 month
2009-01-14 15:20:13 +00:00
John Baldwin
b7f1c1d210 Add a new KTR tracepoint in the KTR_CALLOUT class to note when a callout
routine finishes executing.

MFC after:	1 week
2009-01-13 15:56:53 +00:00
Konstantin Belousov
d19b99278c Do not call namei() while having another user-controlled vnode
locked. Lookup could attempt to recursively lock that vnode.

Do not call vn_start_write(V_WAIT) while vnode is locked, this may
result in a deadlock with suspension.

vfs_busy() the mountpoint before dropping vnode lock for vnode
that was used to look up the mountpoint, to prevent unmount in
between.

Reported and tested by:	pho
Reviewed by:	rwatson
MFC after:	3 weeks
2009-01-08 12:47:30 +00:00
Ed Schouten
fdef61da21 Remove Giant locking from domains list.
During boot, the domain list is locked with Giant. It is not possible to
register any protocols after the system has booted, so the lock is only
used to protect insertion of entries.

There is already a mutex in uipc_domain.c called dom_mtx. Use this mutex
to lock the list, instead of using Giant. It won't matter anything with
respect to performance, but we'll never get rid of Giant if we don't
remove from places where we don't need it.

Approved by:	rwatson
MFC after:	3 weeks
2009-01-04 19:22:53 +00:00
Robert Watson
192a6120fc Remove two further uses (debugging and NULLing) of pr_ousrreq, missed due
to svn commit in the wrong directory.

Spotted by:	bz
2009-01-04 19:16:36 +00:00
Bjoern A. Zeeb
eb76156548 Back out r186615; the sanitizing of the pointers in the error case
is not needed and seems that it will not be needed either.

Pointy hat:	mine, mine, mine and not pho's
2009-01-04 12:18:18 +00:00
Konstantin Belousov
641e2829b6 Extend the struct vm_page wire_count to u_int to avoid the overflow
of the counter, that may happen when too many sendfile(2) calls are
being executed with this vnode [1].

To keep the size of the struct vm_page and offsets of the fields
accessed by out-of-tree modules, swap the types and locations
of the wire_count and cow fields. Add safety checks to detect cow
overflow and force fallback to the normal copy code for zero-copy
sockets. [2]

Reported by:	Anton Yuzhaninov <citrin citrin ru> [1]
Suggested by:	alc [2]
Reviewed by:	alc
MFC after:	2 weeks
2009-01-03 13:24:08 +00:00
Ed Schouten
bcca92c0e5 Fix a corner case in my previous commit.
Even though there are not many setups that have absolutely no console
device, make sure a close() on a TTY doesn't dereference a null pointer.
2009-01-02 23:39:29 +00:00
Ed Schouten
916501c81c Don't let /dev/console be revoked if the TTY below is being closed.
During startup some of the syscons TTY's are used to set attributes like
the screensaver and mouse options. These actions cause /dev/console to
be rendered unusable.

Fix the issue by leaving the TTY opened when it is used as the console
device.

Reported by:	imp
2009-01-02 23:32:43 +00:00
Robert Watson
b523ec24b9 White space and comment tweaks.
MFC after:	3 weeks
2009-01-01 20:03:22 +00:00
Robert Watson
877e88123e Temporary workaround for the limitations of the mbuf flowid field: zero
the field in the mbuf constructors, since otherwise we have no way to
tell if they are valid.  In the future, Kip has plans to add a flag
specifically to indicate validity, which is the preferred model.
2009-01-01 20:03:01 +00:00
Ed Schouten
4cfe479098 Don't clobber sysctl_root()'s error number.
When sysctl() is being called with a buffer that is too small, it will
return ENOMEM. Unfortunately the changes I made the other day sets the
error number to 0, because it just returns the error number of the
copyout(). Revert this part of the change.
2009-01-01 00:19:51 +00:00
Ivan Voras
98a4431181 Document the relationship between enum VM_GUEST and the vm_guest_sysctl_names
array.

Approved by:	gnn (original version)
2008-12-30 23:49:54 +00:00
Peter Holm
1d347f061f Added missing second part of cleaning j->ip[46] as requested by bz
Approved by:	kib (mentor)
Pointy hat:	pho
2008-12-30 20:39:47 +00:00
Peter Holm
bc971b2c82 Make sure that unused j->ip[46] are cleared
Reviewed by:	bz
Approved by:	kib (mentor)
2008-12-30 17:54:25 +00:00
Robert Watson
a9f3c7d2ff Rename mbcnt to mbcnt_delta in uipc_send() -- unlike other local
variables named mbcnt in uipc_usrreq.c, this instance is a delta
rather than a cache of sb_mbcnt.

MFC after:	3 weeks
2008-12-30 16:09:57 +00:00
Konstantin Belousov
7efa697d80 Clear the pointers to the file in the struct filedesc before file is closed
in fdfree. Otherwise, sysctl_kern_proc_filedesc may dereference stale
struct file * values.

Reported and tested by:	pho
MFC after:	1 month
2008-12-30 12:51:56 +00:00
Konstantin Belousov
83e73926ad In r185557, the check for existing negative entry for the given name
did not compared nc_dvp with supplied parent directory vnode pointer.
Add the check and note that now branches for vp != NULL and vp == NULL
are the same, thus can be merged.

Reported and reviewed by:	kan
Tested by:	pho
MFC after:	2 weeks
2008-12-30 12:51:14 +00:00
Ed Schouten
71b6d504c1 Fix compilation. Also move ogetkerninfo() to kern_xxx.c.
It seems I forgot to remove `int error' from a single piece of code. I'm
also moving ogetkerninfo() to kern_xxx.c, because it belongs to the
class of compat system information system calls, not the generic sysctl
code.
2008-12-29 19:24:00 +00:00
Ed Schouten
ddf9d24349 Push down Giant inside sysctl. Also add some more assertions to the code.
In the existing code we didn't really enforce that callers hold Giant
before calling userland_sysctl(), even though there is no guarantee it
is safe. Fix this by just placing Giant locks around the call to the oid
handler. This also means we only pick up Giant for a very short period
of time. Maybe we should add MPSAFE flags to sysctl or phase it out all
together.

I've also added SYSCTL_LOCK_ASSERT(). We have to make sure sysctl_root()
and name2oid() are called with the sysctl lock held.

Reviewed by:	Jille Timmermans <jille quis cx>
2008-12-29 12:58:45 +00:00
Konstantin Belousov
22a448c4d9 vm_map_lock_read() does not increment map->timestamp, so we should
compare map->timestamp with saved timestamp after map read lock is
reacquired, not with saved timestamp + 1. The only consequence of the +1
was unconditional lookup of the next map entry, though.

Tested by:	pho
Approved by:	des
MFC after:	2 weeks
2008-12-29 12:45:11 +00:00
Kip Macy
08a2459ee1 drop rnh lock before destroying it 2008-12-28 14:32:27 +00:00
Bjoern A. Zeeb
34820bbf06 Hide detect_virtual() along with the accompanying string
arrays under #ifndef XEN to make XEN config compile again.
In case of Xen vm_guest is hard coded.

Move the list for the vm_guest sysctl out of the restictive
bounds as the sysctl is there in either case.
2008-12-27 17:19:16 +00:00
Peter Holm
ab62a2d023 Prevent overflow of uio_resid.
Approved by:	kib
2008-12-27 10:13:43 +00:00
Robert Watson
9c232f86ca Following the recent security advisory, add a comment describing our
invariants and approach for protocol switch methods in protsw_init(),
and also some KASSERT's for non-domain init entries in protocol
switch tables: pru_abort and pru_send must both be implemented.

For now, leave those assertions #if 0'd, since there are a few
protocols that violate them in non-harmful ways.  Whether or not we
should enforce pru_abort being implemented for non-stream protocols
is an interesting question: currently abort is only invoked on stream
sockets in situations where un-accepted sockets must be abruptly
closed (i.e., close() on a listen socket with pending connections),
but in principle it is useful for datagram sockets and most datagram
socket types implement it.

MFC after:	3 weeks
2008-12-25 11:32:38 +00:00
Joe Marcus Clarke
4769218f4b Do not KASSERT when vp->v_dd is NULL. Only directories which have had ".."
looked up would have v_dd set to a non-NULL value.  This fixes a panic
seen when running installworld on a diskless system with a separate /usr
file system.

Submitted by:	cracauer
Approved by:	kib
2008-12-23 20:43:42 +00:00
Konstantin Belousov
86dcb537c9 Keep the hold on the vnode during VOP_VPTOCNP() call, allowing the vop
implementation to drop vnode lock, if needed.

Reported and tested by:	pho
2008-12-23 20:04:31 +00:00
Ivan Voras
59d9578919 Add missing newlines to flags tags of CPU topology, for prettier
output.

Reviewed by:	jeff (original version)
Approved by:	gnn (mentor) (original version)
2008-12-23 16:19:59 +00:00
Colin Percival
f0b40b1c97 Prevent cross-site forgery attacks on ftpd(8) due to splitting
long commands into multiple requests. [08:12]

Avoid calling uninitialized function pointers in protocol switch
code. [08:13]

Merry Christmas everybody...

Approved by:	so (cperciva)
Approved by:	re (kensmith)
Security:	FreeBSD-SA-08:12.ftpd, FreeBSD-SA-08:13.protosw
2008-12-23 01:23:09 +00:00
Ed Schouten
3a4d0c86aa Revert r185891.
In r185891 I removed the newlines from messages written to /dev/console,
because it made startup messages from rc-scripts harder to read. This,
unfortunately, causes the kernel message that is printed after a
non-terminated log message to be concatenated.

This could be fixed, but on short term it's better to just revert the
change.

Reported by:	Jaakko Heinonen <jh saunalahti fi>
2008-12-21 21:54:01 +00:00
Ed Schouten
67dd0ccbee Set PTS_FINISHED before waking up any threads.
Inside ptsdrv_{in,out}wakeup() we call KNOTE_LOCKED() to wake up any
kevent(2) users. Because the kqueue handlers are executed synchronously,
we must set PTS_FINISHED before calling ptsdrv_{in,out}wakeup().

Discovered by:	nork
2008-12-21 21:16:57 +00:00
Ed Schouten
9d34a1338c Let wchan names more closely match pre-MPSAFE TTY behaviour.
Right now the wchan strings "ttyinp" and "ttybgw" only differ one
character from the strings we used prior to MPSAFE TTY. Just rename them
back to their pre-MPSAFE TTY counterparts.

Also rename "ttylck" to "ttymtx", which should make it more clear that a
process is blocked on the TTY mutex, not some other form of locking.
2008-12-20 09:36:40 +00:00
Nathan Whitehorn
91416fb268 Modularize the Open Firmware client interface to allow run-time switching
of OFW access semantics, in order to allow future support for real-mode
OF access and flattened device frees. OF client interface modules are
implemented using KOBJ, in a similar way to the PPC PMAP modules.

Because we need Open Firmware to be available before mutexes can be used on
sparc64, changes are also included to allow KOBJ to be used very early in
the boot process by only using the mutex once we know it has been initialized.

Reviewed by:    marius, grehan
2008-12-20 00:33:10 +00:00
Ivan Voras
bb501b18e8 Further beautify the lock strings to be more pleasing to the eye and
self documenting within 6 characters.

Reviewed by:	ed (older version)
Approved by:	gnn (older version)
2008-12-19 14:49:14 +00:00
Ruslan Ermilov
98bd6a1982 Removed a comment made obsolete by revisions 157927 and 174292. 2008-12-18 15:56:12 +00:00
Ivan Voras
3610a2260b By popular request, stringify kern.vm_guest sysctl. Now it returns a
short, self-documenting string describing the detected virtual
environment.

Approved by:	gnn (mentor) (earlier version)
2008-12-18 15:34:38 +00:00
Ivan Voras
0e469db660 Remove spaces in wait object names to make top (1) output prettier and
unbreak scripts that examine ps (1) output.

Reviewed by:	ed
Approved by:	gnn (mentor)
2008-12-18 15:25:33 +00:00
Konstantin Belousov
548066ea66 The quotactl, statfs and fstatfs syscall implementations may dereference
NULL pointer to struct mount if the looked up vnode is reclaimed. Also,
these syscalls only mnt_ref() the mp, still allowing it to be unmounted;
only struct mount memory is kept from being reused.

Lock the vnode when doing name lookup, then reference its mount point,
unlock the vnode and vfs_busy the mountpoint. This sequence shall take
care of both races.

Reported and tested by:	pho
Discussed with:	attilio
MFC after:	1 month
2008-12-18 12:01:19 +00:00
Konstantin Belousov
2cfddad734 Do not return success and doomed vnode from lookup. LK_UPGRADE allows
the vnode to be reclaimed.

Tested by:	pho
MFC after:	1 month
2008-12-18 11:58:12 +00:00
Ivan Voras
3dc309114a Introduce a sysctl kern.vm_guest that reflects what the kernel knows about
it running under a virtual environment. This also introduces a globally
accessible variable vm_guest that can be used where appropriate in the
kernel to inspect this environment.

To make it easier for the long run, an enum VM_GUEST is also introduced,
which could possibly be factored out in a header somewhere (but the
question is where - vm/vm_param.h? sys/param.h?) so it eventually becomes
a part of the standard KPI. In any case, it's a start.

The purpose of all this isn't to absolutely detect that the OS is running
under a virtual environment (cf. "redpill") but to allow the parts of the
kernel and the userland that care about this particular aspect and can do
something useful depending on it to have a standardised interface. Reducing
kern.hz is one example but there are other things that could be done like
avoiding context switches, not using CPU instructions that are known to be
slow in emulation, possibly different strategies in VM (memory) allocation,
CPU scheduling, etc.

It isn't clear if the JAILS/VIMAGE functionality should also be exposed
by this particular mechanism (probably not since they're not "full"
virtual hardware environments). Sometime in the future another sysctl and
a variable could be introduced to reflect if the kernel supports any kind
of virtual hosting (e.g. VMWare VMI, Xen dom0).

Reviewed by:	silence from src-commiters@, virtualization@, kmacy@
Approved by:	gnn (mentor)
Security:	Obscurity doesn't help.
2008-12-17 19:57:12 +00:00
Peter Wemm
a3ac8c94cf Remove sysctl debug.elf_trace and the trace field in auxargs. They go
nowhere.  It used to be the equivalent of $LD_DEBUG in rtld-elf.
Elf_Auxargs is an internal structure.
2008-12-17 16:54:29 +00:00
Warner Losh
35c2a5a852 Minor style(9) nit. 2008-12-17 16:25:20 +00:00
Konstantin Belousov
6f3475454e Remove two remnant uses of AT_DEBUG. 2008-12-17 13:13:35 +00:00
Attilio Rao
4a0f807602 1) Fix a deadlock in the VFS:
- threadA runs vfs_rel(mp1)
- threadB does unmount the mp1 fs, sets MNTK_UNMOUNT and drop MNT_ILOCK()
- threadA runs vfs_busy(mp1) and, as long as, MNTK_UNMOUNT is set, sleeps
  waiting for threadB to complete the unmount
- threadB, in vfs_mount_destroy(), finds mnt_lock > 0 and sleeps waiting
  for the refcount to expire.

Fix the deadlock by adding a flag called MNTK_REFEXPIRE which signals the
unmounter is waiting for mnt_ref to expire.
The vfs_busy contenders got awake, fails, and if they retry the
MNTK_REFEXPIRE won't allow them to sleep again.

2) Simplify significantly the code of vfs_mount_destroy() trimming
   unnecessary codes:
   - as long as any reference exited, it is no-more possible to have
     write-op (primarty and secondary) in progress.
   - it is no needed to drop and reacquire the mount lock.
   - filling the structures with dummy values is unuseful as long as
     it is going to be freed.

Tested by:	pho, Andrea Barberio <insomniac at slackware dot it>
Discussed with:	kib
2008-12-16 23:16:10 +00:00
Alexander Motin
d288bcc4df If possible, try to obtain max_mhz on cpufreq attach instead of first request.
On HyperThreading CPUs logical cores have same frequency, so setting it
on any core will change the other's one. In most cases first request
to the second core will be the "set" request, done after setting frequency
of the first core. In such case second CPU will obtain throttled frequency
of the first core as it's max_mhz making cpufreq broken due to different
frequency sets.
2008-12-16 01:24:05 +00:00
Alexander Motin
a9385ad10f Change ttyhook_register() second argument from thread to process pointer.
Thread was not really needed there, while previous ng_tty implementation
that used thread pointer had locking issues (using sx while holding mutex).
2008-12-13 21:17:46 +00:00
Joseph Koshy
6fe00c7876 - Bug fix: prevent a thread from migrating between CPUs between the
time it is marked for user space callchain capture in the NMI
  handler and the time the callchain capture callback runs.

- Improve code and control flow clarity by invoking hwpmc(4)'s user
  space callchain capture callback directly from low-level code.

Reviewed by:	jhb (kern/subr_trap.c)
Testing (various patch revisions): gnn,
		Fabien Thomas <fabien dot thomas at netasq dot com>,
		Artem Belevich <artemb at gmail dot com>
2008-12-13 13:07:12 +00:00
Ed Schouten
d4892ee51e Add FIONREAD to pseudo-terminal master devices.
All ioctl()'s that aren't implemented by pts(4) are forwarded to the TTY
itself. Unfortunately this is not correct for FIONREAD, because it will
give the wrong amount of bytes that are available to read.

Tested by:	keramida
Reminded by:	keramida
2008-12-13 07:23:55 +00:00
Konstantin Belousov
cd2983ca71 Uio_yield() already does DROP_GIANT/PICKUP_GIANT, no need to repeat this
around the call.

Noted by:  bde
2008-12-12 14:03:04 +00:00
Konstantin Belousov
c7462f4387 Reference the vmspace of the process being inspected by procfs, linprocfs
and sysctl kern_proc_vmmap handlers.

Reported and tested by:	pho
Reviewed by:	rwatson, des
MFC after:	1 week
2008-12-12 12:12:36 +00:00
Konstantin Belousov
af80b2c901 The userland_sysctl() function retries sysctl_root() until returned
error is not EAGAIN. Several sysctls that inspect another process use
p_candebug() for checking access right for the curproc. p_candebug()
returns EAGAIN for some reasons, in particular, for the process doing
exec() now. If execing process tries to lock Giant, we get a livelock,
because sysctl handlers are covered by Giant, and often do not sleep.

Break the livelock by dropping Giant and allowing other threads to
execute in the EAGAIN loop.

Also, do not return EAGAIN from p_candebug() when process is executing,
use more appropriate EBUSY error [1].

Reported and tested by:	pho
Suggested by:	rwatson [1]
Reviewed by:	rwatson, des
MFC after:	1 week
2008-12-12 12:06:28 +00:00
Joe Marcus Clarke
b9022449b3 Add a new VOP, VOP_VPTOCNP, which translates a vnode to its component name
on a best-effort basis.  Teach vn_fullpath to use this new VOP if a
regular VFS cache lookup fails.  This VOP is designed to supplement the
VFS cache to provide a better chance that a vnode-to-name lookup will
succeed.

Currently, an implementation for devfs is being committed.  The default
implementation is to return ENOENT.

A big thanks to kib for the mentorship on this, and to pho for running it
through his stress test suite.

Reviewed by:	arch
Approved by:	kib
2008-12-12 00:57:38 +00:00
Ed Schouten
1ff90be789 Add kqueue()-support to pseudo-terminal master devices.
One thing I didn't expect many applications to use, was kqueue() on
pseudo-terminal master devices. There are applications that use kqueue()
on the TTY itself (rtorrent, etc). That doesn't mean we shouldn't
implement this. Libraries like libevent use kqueue() by default, which
means they wouldn't be able to use kqueue().

The old TTY layer implements a very broken version of kqueue() by
performing the actual polling on the TTY device.

Discussed with:	peter
2008-12-11 21:44:02 +00:00
Bjoern A. Zeeb
9ea9ef7e89 Order #includes - also to reduce diffs with vimage branches in p4.
Sponsored by:	The FreeBSD Foundation
2008-12-11 16:09:31 +00:00
Bjoern A. Zeeb
0f1fe22db5 Correctly check the number of prison states to not access anything
outside the prison_states array.
When checking if there is a name configured for the prison, check the
first character to not be '\0' instead of checking if the char array
is present, which it always is. Note, that this is different for the
*jailname in the syscall.

Found with:	Coverity Prevent(tm)
CID:		4156, 4155
MFC after:	4 weeks (just that I get the mail)
2008-12-11 01:04:25 +00:00
Marko Zec
385195c062 Conditionally compile out V_ globals while instantiating the appropriate
container structures, depending on VIMAGE_GLOBALS compile time option.

Make VIMAGE_GLOBALS a new compile-time option, which by default will not
be defined, resulting in instatiations of global variables selected for
V_irtualization (enclosed in #ifdef VIMAGE_GLOBALS blocks) to be
effectively compiled out.  Instantiate new global container structures
to hold V_irtualized variables: vnet_net_0, vnet_inet_0, vnet_inet6_0,
vnet_ipsec_0, vnet_netgraph_0, and vnet_gif_0.

Update the VSYM() macro so that depending on VIMAGE_GLOBALS the V_
macros resolve either to the original globals, or to fields inside
container structures, i.e. effectively

#ifdef VIMAGE_GLOBALS
#define V_rt_tables rt_tables
#else
#define V_rt_tables vnet_net_0._rt_tables
#endif

Update SYSCTL_V_*() macros to operate either on globals or on fields
inside container structs.

Extend the internal kldsym() lookups with the ability to resolve
selected fields inside the virtualization container structs.  This
applies only to the fields which are explicitly registered for kldsym()
visibility via VNET_MOD_DECLARE() and vnet_mod_register(), currently
this is done only in sys/net/if.c.

Fix a few broken instances of MODULE_GLOBAL() macro use in SCTP code,
and modify the MODULE_GLOBAL() macro to resolve to V_ macros, which in
turn result in proper code being generated depending on VIMAGE_GLOBALS.

De-virtualize local static variables in sys/contrib/pf/net/pf_subr.c
which were prematurely V_irtualized by automated V_ prepending scripts
during earlier merging steps.  PF virtualization will be done
separately, most probably after next PF import.

Convert a few variable initializations at instantiation to
initialization in init functions, most notably in ipfw.  Also convert
TUNABLE_INT() initializers for V_ variables to TUNABLE_FETCH_INT() in
initializer functions.

Discussed at:	devsummit Strassburg
Reviewed by:	bz, julian
Approved by:	julian (mentor)
Obtained from:	//depot/projects/vimage-commit2/...
X-MFC after:	never
Sponsored by:	NLnet Foundation, The FreeBSD Foundation
2008-12-10 23:12:39 +00:00
Bjoern A. Zeeb
629386598e Make sure nmbclusters are initialized before maxsockets
by running the tunable_mbinit() SYSINIT at SI_ORDER_MIDDLE
before the init_maxsockets() SYSINT at SI_ORDER_ANY.

Reviewed by:		rwatson, zec
Sponsored by:		The FreeBSD Foundation
MFC after:		4 weeks
2008-12-10 22:17:09 +00:00
Bjoern A. Zeeb
36b5ba0c49 Style changes only. Put the return type on an extra line[1] and
add an empty line at the beginning as we do not have any local
variables.

Submitted by:	rwatson [1]
Reviewed by:	rwatson
MFC after:	4 weeks
2008-12-10 22:10:37 +00:00
Ed Schouten
d16ebcd4fe Remove added newlines from logged messages written to /dev/console.
The /dev/console device node logs all strings that are written to it.
When the string does not contain a trailing newline, it appends one. I
can imagine this was useful a long time ago, but with our current
rc-scripts, it generates a whole bunch of messages that look like:

| Configuring syscons:
|  blanktime
| .

By not appending the newlines, the output of `dmesg -a' is now (almost?)
exactly the same as what the user will see on the console device
(syscons, uart).
2008-12-10 21:48:05 +00:00
John Baldwin
3858a1f4f5 - Add 32-bit compat system calls for VFS_AIO. The system calls live in the
aio code and are registered via the recently added SYSCALL32_*() helpers.
- Since the aio code likes to invoke fuword and suword a lot down in the
  "bowels" of system calls, add a structure holding a set of operations for
  things like storing errors, copying in the aiocb structure, storing
  status, etc.  The 32-bit system calls use a separate operations vector to
  handle fuword32 vs fuword, etc.  Also, the oldsigevent handling is now
  done by having seperate operation vectors with different aiocb copyin
  routines.
- Split out kern_foo() functions for the various AIO system calls so the
  32-bit front ends can manage things like copying in and converting
  timespec structures, etc.
- For both the native and 32-bit aio_suspend() and lio_listio() calls,
  just use copyin() to read the array of aiocb pointers instead of using
  a for loop that iterated over fuword/fuword32.  The error handling in
  the old case was incomplete (lio_listio() just ignored any aiocb's that
  it got an EFAULT trying to read rather than reporting an error), and
  possibly slower.

MFC after:	1 month
2008-12-10 20:56:19 +00:00
Kip Macy
e1d881ba31 add RW_SYSINIT_FLAGS macro and rw_sysinit_flags initialization function 2008-12-08 21:46:55 +00:00
Jung-uk Kim
9bd2cbe43f - Detect Bochs BIOS variants and use HZ_VM as well.
- Free kernel environment variable after its use.
- Fix style(9) nits.
2008-12-08 18:39:59 +00:00
Konstantin Belousov
118d0afa28 Do drop vm map lock earlier in the sysctl_kern_proc_vmmap(), to avoid
locking a vnode while having vm map locked.

Reported and tested by:	pho
MFC after:	1 week
2008-12-08 12:29:30 +00:00
Kip Macy
3120b9d428 - convert radix node head lock from mutex to rwlock
- make radix node head lock not recursive
 - fix LOR in rtexpunge
 - fix LOR in rtredirect

Reviewed by:	sam
2008-12-07 21:15:43 +00:00
Konstantin Belousov
aeb325719a Several threads in a process may do vfork() simultaneously. Then, all
parent threads sleep on the parent' struct proc until corresponding
child releases the vmspace. Each sleep is interlocked with proc mutex of
the child, that triggers assertion in the sleepq_add(). The assertion
requires that at any time, all simultaneous sleepers for the channel use
the same interlock.

Silent the assertion by using conditional variable allocated in the
child. Broadcast the variable event on exec() and exit().

Since struct proc * sleep wait channel is overloaded for several
unrelated events, I was unable to remove wakeups from the places where
cv_broadcast() is added, except exec().

Reported and tested by:	ganbold
Suggested and reviewed by:	jhb
MFC after:	2 week
2008-12-05 20:50:24 +00:00
John Baldwin
75444a8590 When the SYSINIT() to load a module invokes the MOD_LOAD event successfully,
move that module to the head of the associated linker file's list of modules.
The end result is that once all the modules are loaded, they are sorted in
the reverse of their load order.  This causes the kernel linker to invoke
the MOD_QUIESCE and MOD_UNLOAD events in the reverse of the order that
MOD_LOAD was invoked.  This means that the ordering of MOD_LOAD events that
is set by the SI_* paramters to DECLARE_MODULE() are now honored in the same
order they would be for SYSUNINIT() for the MOD_QUIESCE and MOD_UNLOAD
events.

MFC after:	1 month
2008-12-05 16:47:30 +00:00
John Baldwin
b4824b48b4 - Invoke MOD_QUIESCE on all modules in a linker file (kld) before
unloading any modules.  As a result, if any module veto's an unload
  request via MOD_QUIESCE, the entire set of modules for that linker
  file will remain loaded and active now rather than leaving the kld
  in a weird state where some modules are loaded and some are unloaded.
- This also moves the logic for handling the "forced" unload flag out of
  kern_module.c and into kern_linker.c which is a bit cleaner.
- Add a module_name() routine that returns the name of a module and use that
  instead of printing pointer values in debug messages when a module fails
  MOD_QUIESCE or MOD_UNLOAD.

MFC after:	1 month
2008-12-05 13:40:25 +00:00
Bjoern A. Zeeb
118258f5c2 Fix a credential reference leak. [1]
Close subtle but relatively unlikely race conditions when
propagating the vnode write error to other active sessions
tracing to the same vnode, without holding a reference on
the vnode anymore. [2]

PR:		kern/126368 [1]
Submitted by:	rwatson [2]
Reviewed by:	kib, rwatson
MFC after:	4 weeks
2008-12-03 15:54:35 +00:00
Bjoern A. Zeeb
4b79449e2f Rather than using hidden includes (with cicular dependencies),
directly include only the header files needed. This reduces the
unneeded spamming of various headers into lots of files.

For now, this leaves us with very few modules including vnet.h
and thus needing to depend on opt_route.h.

Reviewed by:	brooks, gnn, des, zec, imp
Sponsored by:	The FreeBSD Foundation
2008-12-02 21:37:28 +00:00
Konstantin Belousov
d6568724e1 Shared lookup makes it possible to create several negative cache
entries for one name. Then, creating inode with that name would remove
one entry, leaving others dormant. Reclaiming the vnode would uncover
negative entries, causing false return of ENOENT from the calls like
stat, that do not create inode.

Prevent creation of the duplicated negative entries.

Reported and debugged with:	pho
Reviewed by:	jhb
X-MFC:	after shared lookup changes
2008-12-02 11:14:16 +00:00
Peter Wemm
43151ee6cf Merge user/peter/kinfo branch as of r185547 into head.
This changes struct kinfo_filedesc and kinfo_vmentry such that they are
same on both 32 and 64 bit platforms like i386/amd64 and won't require
sysctl wrapping.

Two new OIDs are assigned.  The old ones are available under
COMPAT_FREEBSD7 - but it isn't that simple.  The superceded interface
was never actually released on 7.x.

The other main change is to pack the data passed to userland via the
sysctl.  kf_structsize and kve_structsize are reduced for the copyout.
If you have a process with 100,000+ sockets open, the unpacked records
require a 132MB+ copyout.  With packing, it is "only" ~35MB.  (Still
seriously unpleasant, but not quite as devastating).  A similar problem
exists for the vmentry structure - have lots and lots of shared libraries
and small mmaps and its copyout gets expensive too.

My immediate problem is valgrind.  It traditionally achieves this
functionality by parsing procfs output, in a packed format.  Secondly, when
tracing 32 bit binaries on amd64 under valgrind, it uses a cross compiled
32 bit binary which ran directly into the differing data structures in 32
vs 64 bit mode.  (valgrind uses this to track file descriptor operations
and this therefore affected every single 32 bit binary)

I've added two utility functions to libutil to unpack the structures into
a fixed record length and to make it a little more convenient to use.
2008-12-02 06:50:26 +00:00
Alexander Kabaev
6ee7dd87ba Shared memory objects that have size which is not necessarily equal to
exact multiple of system page size should still be allowed to be mapped
in their entirety to match the regular vnode backed file behavior.

Reported by: ed
Reviewed by: jhb
2008-12-01 22:33:50 +00:00
Ken Smith
f34015d47b Catch up with the disappearance of sys/dev/hfa. 2008-12-01 14:34:42 +00:00
Attilio Rao
ccc55b33b7 Fix an inverted check introduced in r184554.
Submitted by:	tegge
Pointy hat to:	me
2008-12-01 03:00:26 +00:00
David Xu
6d9b63d6c8 Revision 184199 had not been fully reverted, add missing piece.
Reported by: phk
2008-12-01 01:54:55 +00:00
Bjoern A. Zeeb
d465a41d3b Unbreak the no-networks (no INET/6) build that I broke with
the commit in r185435.

Pointyhat:	no, but I could need a ski cap for the winter
2008-11-29 16:17:39 +00:00
Bjoern A. Zeeb
413628a7e3 MFp4:
Bring in updated jail support from bz_jail branch.

This enhances the current jail implementation to permit multiple
addresses per jail. In addtion to IPv4, IPv6 is supported as well.
Due to updated checks it is even possible to have jails without
an IP address at all, which basically gives one a chroot with
restricted process view, no networking,..

SCTP support was updated and supports IPv6 in jails as well.

Cpuset support permits jails to be bound to specific processor
sets after creation.

Jails can have an unrestricted (no duplicate protection, etc.) name
in addition to the hostname. The jail name cannot be changed from
within a jail and is considered to be used for management purposes
or as audit-token in the future.

DDB 'show jails' command was added to aid debugging.

Proper compat support permits 32bit jail binaries to be used on 64bit
systems to manage jails. Also backward compatibility was preserved where
possible: for jail v1 syscalls, as well as with user space management
utilities.

Both jail as well as prison version were updated for the new features.
A gap was intentionally left as the intermediate versions had been
used by various patches floating around the last years.

Bump __FreeBSD_version for the afore mentioned and in kernel changes.

Special thanks to:
- Pawel Jakub Dawidek (pjd) for his multi-IPv4 patches
  and Olivier Houchard (cognet) for initial single-IPv6 patches.
- Jeff Roberson (jeff) and Randall Stewart (rrs) for their
  help, ideas and review on cpuset and SCTP support.
- Robert Watson (rwatson) for lots and lots of help, discussions,
  suggestions and review of most of the patch at various stages.
- John Baldwin (jhb) for his help.
- Simon L. Nielsen (simon) as early adopter testing changes
  on cluster machines as well as all the testers and people
  who provided feedback the last months on freebsd-jail and
  other channels.
- My employer, CK Software GmbH, for the support so I could work on this.

Reviewed by:	(see above)
MFC after:	3 months (this is just so that I get the mail)
X-MFC Before:   7.2-RELEASE if possible
2008-11-29 14:32:14 +00:00
Konstantin Belousov
6179164448 In the nfsrv_fhtovp(), after the vfs_getvfs() function found the pointer
to the fs, but before a vnode on the fs is locked, unmount may free fs
structures, causing access to destroyed data and freed memory.

Introduce a vfs_busymp() function that looks up and busies found
fs while mountlist_mtx is held. Use it in nfsrv_fhtovp() and in the
implementation of the handle syscalls.

Two other uses of the vfs_getvfs() in the vfs_subr.c, namely in
sysctl_vfs_ctl and vfs_getnewfsid seems to be ok. In particular,
sysctl_vfs_ctl is protected by Giant by being a non-sleeping sysctl
handler, that prevents Giant-locked unmount code to interfere with it.

Noted by:	tegge
Reviewed by:	dfr
Tested by:	pho
MFC after:	1 month
2008-11-29 13:34:59 +00:00
Pawel Jakub Dawidek
0c6a80e78d Improve KASSERT() call a bit:
- Print flags in hex.
- Note that flags can be fine and panic can be due unexpected error condition.
- Remove redundant new line character.

Eventhough panic message excess 80 characters keep it in one line so it is
easier to grep.
2008-11-29 12:40:14 +00:00
Bjoern A. Zeeb
b9f0b66c75 With the permissions of phk@ change the license on kern_jail.c
to a 2 clause BSD license.
2008-11-28 19:23:46 +00:00
Ed Schouten
1cbae70533 Fix matching of message queues by name.
The mqfs_search() routine uses strncmp() to match message queue objects
by name. This is because it can be called from environments where the
file name is not null terminated (the VFS for example).

Unfortunately it doesn't compare the lengths of the message queue names,
which means if a system has "Queue12345", the name "Queue" will also
match.

I noticed this when a student of mine handed in an exercise using
message queues with names "Queue2" and "Queue".

Reviewed by:	rink
2008-11-28 14:53:18 +00:00
Konstantin Belousov
b7a813fc21 Explicitely note that destroy_dev() sleeps.
Requested by:	ed (some time ago), Jaakko Heinonen <jh saunalahti fi>
2008-11-27 16:47:25 +00:00
Ganbold Tsagaankhuu
559b717f5e Remove unused variable.
Found with:     Coverity Prevent(tm)
CID: 3664

Approved by: kib
2008-11-27 04:40:37 +00:00
Marko Zec
97021c2464 Merge more of currently non-functional (i.e. resolving to
whitespace) macros from p4/vimage branch.

Do a better job at enclosing all instantiations of globals
scheduled for virtualization in #ifdef VIMAGE_GLOBALS blocks.

De-virtualize and mark as const saorder_state_alive and
saorder_state_any arrays from ipsec code, given that they are never
updated at runtime, so virtualizing them would be pointless.

Reviewed by:  bz, julian
Approved by:  julian (mentor)
Obtained from:        //depot/projects/vimage-commit2/...
X-MFC after:  never
Sponsored by: NLnet Foundation, The FreeBSD Foundation
2008-11-26 22:32:07 +00:00
Joe Marcus Clarke
ef61995ebd Move vn_fullpath1() outside of FILEDESC locking. This is being done in
advance of teaching vn_fullpath1() how to query file systems for
vnode-to-name mappings when cache lookups fail.

Thanks to kib for guidance and patience on this process.

Reviewed by:	kib
Approved by:	kib
2008-11-25 15:36:15 +00:00
Ed Maste
6ffb78d173 Correct typo in comment: thier -> their 2008-11-24 19:28:52 +00:00
David Malone
27d68f904f It's possible that the dump device has gone away after it was
configured, change the message to let people know this is a
possibility. I've slightly changed the message from the one
submitted by Pekka to keep the printf on one line.

Submitted by:	Pekka Savola <pekkas@netcore.fi>
2008-11-23 21:05:22 +00:00
Konstantin Belousov
b4cf0e62f4 Add sv_flags field to struct sysentvec with intention to provide description
of the ABI of the currently executing image. Change some places to test
the flags instead of explicit comparing with address of known sysentvec
structures to determine ABI features.

Discussed with:	dchagin, imp, jhb, peter
2008-11-22 12:36:15 +00:00