Commit Graph

12693 Commits

Author SHA1 Message Date
Hiroki Sato
cf8b832511 Fix input validation in SO_SETFIB.
Reviewed by:	bz
MFC after:	1 day
2012-02-04 15:00:26 +00:00
Bjoern A. Zeeb
ee799639e8 Add SO_SETFIB option support on PF_INET6 sockets and allow inheriting the
FIB number from the process, as set by setfib(2), on socket creation.

Sponsored by:	Cisco Systems, Inc.
2012-02-03 11:00:53 +00:00
Konstantin Belousov
6af519cf18 Add kqueue support to /dev/klog.
Submitted by:	Mateusz Guzik <mjguzik gmail com>
PR:	  kern/156423
MFC after:	1 weeks
2012-02-01 14:34:52 +00:00
David Xu
fde809356a If multiple threads call kevent() to get AIO events on same kqueue fd,
it is possible that a single AIO event will be reported to multiple
threads, it is not threading friendly, and the existing API can not
control this behavior.
Allocate a kevent flags field sigev_notify_kevent_flags for AIO event
notification in sigevent, and allow user to pass EV_CLEAR, EV_DISPATCH
or EV_ONESHOT to AIO kernel code, user can control whether the event
should be cleared once it is retrieved by a thread. This change should
be comptaible with existing application, because the field should have
already been zero-filled, and no additional action will be taken by
kernel.

PR:	kern/156567
2012-02-01 02:53:06 +00:00
Konstantin Belousov
6ad1ff09cc A debugger which requested PT_FOLLOW_FORK should get the notification
about new child not only when doing PT_TO_SCX, but also for PT_CONTINUE.
If TDB_FORK flag is set, always issue a stop, the same as is done for
TDB_EXEC.

Reported by:	Dmitry Mikulin <dmitrym juniper net>
MFC after:	1 week
2012-01-30 20:00:29 +00:00
John Baldwin
2bd3e4c2c2 Refine the implementation of POSIX_FADV_NOREUSE for the read(2) case such
that instead of using direct I/O it allows read-ahead similar to
POSIX_FADV_NORMAL, but invokes VOP_ADVISE(POSIX_FADV_DONTNEED) after the
read(2) has completed to purge just-read data.  The write(2) path continues
to use direct I/O for POSIX_FADV_NOREUSE for now.  Note that NOREUSE works
optimally if an application reads and writes full fs blocks.
2012-01-30 19:35:15 +00:00
Doug Ambrisko
8e9fc27818 When detaching an AIO or LIO requests grab the lock and tell knlist_remove
that we have the lock now.  This cleans up a locking panic ASSERT when
knlist_empty is called without a lock when INVARIANTS etc. are turned.

Reviewed by:	kib jhb
MFC after:	1 week
2012-01-30 19:19:22 +00:00
Konstantin Belousov
62c625fdd2 Finally, try to enable the nxstacks on amd64 and powerpc64 for both 64bit
and 32bit ABIs. Also try to enable nxstacks for PAE/i386 when supported,
and some variants of powerpc32.

MFC after:	2 months (if ever)
2012-01-30 07:56:00 +00:00
Attilio Rao
5d7380f8e3 Avoid to check the same cache line/variable from all the locking
primitives by breaking stop_scheduler into a per-thread variable.
Also, store the new td_stopsched very close to td_*locks members as
they will be accessed mostly in the same codepaths as td_stopsched and
this results in avoiding a further cache-line pollution, possibly.

STOP_SCHEDULER() was pondered to use a new 'thread' argument, in order to
take advantage of already cached curthread, but in the end there should
not really be a performance benefit, while introducing a KPI breakage.

In collabouration with:	flo
Reviewed by:	avg
MFC after:	3 months (or never)
X-MFC:		r228424
2012-01-28 14:00:21 +00:00
Gleb Smirnoff
94fce84763 Fix size check, that prevents getting negative after casting
to a signed type

Reviewed by:	bde
2012-01-27 08:58:58 +00:00
Kenneth D. Merry
7e949c467c Xen netback driver rewrite.
share/man/man4/Makefile,
share/man/man4/xnb.4,
sys/dev/xen/netback/netback.c,
sys/dev/xen/netback/netback_unit_tests.c:

	Rewrote the netback driver for xen to attach properly via newbus
	and work properly in both HVM and PVM mode (only HVM is tested).
	Works with the in-tree FreeBSD netfront driver or the Windows
	netfront driver from SuSE.  Has not been extensively tested with
	a Linux netfront driver.  Does not implement LRO, TSO, or
	polling.  Includes unit tests that may be run through sysctl
	after compiling with XNB_DEBUG defined.

sys/dev/xen/blkback/blkback.c,
sys/xen/interface/io/netif.h:

	Comment elaboration.

sys/kern/uipc_mbuf.c:

	Fix page fault in kernel mode when calling m_print() on a
	null mbuf.  Since m_print() is only used for debugging, there
	are no performance concerns for extra error checking code.

sys/kern/subr_scanf.c:

	Add the "hh" and "ll" width specifiers from C99 to scanf().
	A few callers were already using "ll" even though scanf()
	was handling it as "l".

Submitted by:	Alan Somers <alans@spectralogic.com>
Submitted by:	John Suykerbuyk <johns@spectralogic.com>
Sponsored by:	Spectra Logic
MFC after:	1 week
Reviewed by:	ken
2012-01-26 16:35:09 +00:00
Gleb Smirnoff
434ea137cc Although aio_nbytes is size_t, later is is signed to
casted types: to ssize_t in filesystem code and to
int in buf code, thus supplying a negative argument
leads to kernel panic later. To fix that check user
supplied argument in the beginning of syscall.

Submitted by:	Maxim Dounin <mdounin mdounin.ru>, maxim@
2012-01-26 11:59:48 +00:00
Konstantin Belousov
abc942b56c When doing vflush(WRITECLOSE), clean vnode pages.
Unmounts do vfs_msync() before calling VFS_UNMOUNT(), but there is
still a race allowing a process to dirty pages after msync
finished. Remounts rw->ro just left dirty pages in system.

Reviewed by:	alc, tegge (long time ago)
Tested by:	pho
MFC after:	2 weeks
2012-01-25 20:54:09 +00:00
Konstantin Belousov
d5210589b7 Fix remaining calls to cache_enter() in both NFS clients to provide
appropriate timestamps.  Restore the assertions which verify that
NCF_TS is set when timestamp is asked for.

Reviewed by:  jhb (previous version)
MFC after:    2 weeks
2012-01-25 20:48:20 +00:00
Mikolaj Golub
45efc9b4aa Fix CTL flags in the declarations of KERN_PROC_ENV, AUXV and
PS_STRINGS sysctls: they are read only.

MFC after:	1 week
2012-01-25 20:15:58 +00:00
Konstantin Belousov
7a7e609a32 Apparently, both nfs clients do not use cache_enter_time()
consistently, creating some namecache entries without NCF_TS flag.
This causes panic due to failed assertion.

As a temporal relief, remove the assert. Return epoch timestamp for
the entries without timestamp if asked.

While there, consolidate the code which returns timestamps, into a
helper cache_out_ts().

Discussed with:	 jhb
MFC after: 2 weeks
2012-01-23 17:09:23 +00:00
Gleb Smirnoff
93a1b4c4cf Convert panic()s to KASSERT()s. This is an optimisation for
hashdestroy() since in absence of INVARIANTS a compiler
will drop the entire for() cycle.
2012-01-23 16:31:46 +00:00
Mikolaj Golub
8854fe3915 Change kern.proc.rlimit sysctl to:
- retrive only one, specified limit for a process, not the whole
  array, as it was previously (the sysctl has been added recently and
  has not been backported to stable yet, so this change is ok);

- allow to set a resource limit for another process.

Submitted by:	Andrey Zonov <andrey at zonov.org>
Discussed with:	kib
Reviewed by:	kib
MFC after:	2 weeks
2012-01-22 20:25:00 +00:00
Pawel Jakub Dawidek
9b9a01792d TDF_* flags should be used with td_flags field and TDP_* flags should be used
with td_pflags field. Correct two places where it was not the case.

Discussed with:	kib
MFC after:	1 week
2012-01-22 11:01:36 +00:00
Konstantin Belousov
c2b396f294 Remove the nc_time and nc_ticks elements from struct namecache, and
provide struct namecache_ts which is the old struct namecache. Only
allocate struct namecache_ts if non-null struct timespec *tsp was
passed to cache_enter_time, otherwise use struct namecache.

Change struct namecache allocation and deallocation macros into static
functions, since logic becomes somewhat twisty.  Provide accessor for
the nc_name member of struct namecache to hide difference between
struct namecache and namecache_ts.

The aim of the change is to not waste 20 bytes per small namecache
entry.

Reviewed by:	 jhb
MFC after: 2 weeks
X-MFC-note:  after r230394
2012-01-22 01:11:06 +00:00
Martin Matuska
6dfe0a3dc2 Use separate buffer for global path to avoid overflow of path buffer.
Reviewed by:	jamie@
MFC after:	3 weeks
2012-01-21 00:06:21 +00:00
John Baldwin
5aefb4cbbf Close a race in NFS lookup processing that could result in stale name cache
entries on one client when a directory was renamed on another client.  The
root cause for the stale entry being trusted is that each per-vnode nfsnode
structure has a single 'n_ctime' timestamp used to validate positive name
cache entries.  However, if there are multiple entries for a single vnode,
they all share a single timestamp.  To fix this, extend the name cache
to allow filesystems to optionally store a timestamp value in each name
cache entry.  The NFS clients now fetch the timestamp associated with
each name cache entry and use that to validate cache hits instead of the
timestamps previously stored in the nfsnode.  Another part of the fix is
that the NFS clients now use timestamps from the post-op attributes of
RPCs when adding name cache entries rather than pulling the timestamps out
of the file's attribute cache.  The latter is subject to races with other
lookups updating the attribute cache concurrently.  Some more details:
- Add a variant of nfsm_postop_attr() to the old NFS client that can return
  a vattr structure with a copy of the post-op attributes.
- Handle lookups of "." as a special case in the NFS clients since the name
  cache does not store name cache entries for ".", so we cannot get a
  useful timestamp.  It didn't really make much sense to recheck the
  attributes on the the directory to validate the namecache hit for "."
  anyway.
- ABI compat shims for the name cache routines are present in this commit
  so that it is safe to MFC.

MFC after:	2 weeks
2012-01-20 20:02:01 +00:00
Konstantin Belousov
2974cc36f7 Use shared lock for the executable vnode in the exec path after the
VV_TEXT changes are handled. Assert that vnode is exclusively locked at
the places that modify VV_TEXT.

Discussed with:	alc
MFC after:	3 weeks
2012-01-19 23:03:31 +00:00
Alan Cox
1dfab8025e Explain why it is safe to unlock the vnode.
Requested by:	kib
2012-01-17 16:20:50 +00:00
Kirk McKusick
cc672d3599 Make sure all intermediate variables holding mount flags (mnt_flag)
and that all internal kernel calls passing mount flags are declared
as uint64_t so that flags in the top 32-bits are not lost.

MFC after: 2 weeks
2012-01-17 01:08:01 +00:00
Alan Cox
292177e67a Improve abstraction. Eliminate direct access by elf*_load_section()
to an OBJT_VNODE-specific field of the vm object.  The same
information can be just as easily obtained from the struct vattr that
is in struct image_params if the latter is passed to
elf*_load_section().  Moreover, by replacing the vmspace and vm
object parameters to elf*_load_section() with a struct image_params
parameter, we actually reduce the size of the object code.

In collaboration with:	kib
2012-01-17 00:27:32 +00:00
Sergey Kandaurov
037f43d3ef Be pedantic and change // comment to C-style one.
Noticed by:		Bruce Evans
2012-01-16 20:42:56 +00:00
Kevin Lo
575cabed9e Fix a style bug
Spotted by:	avg
2012-01-16 14:54:48 +00:00
David Xu
29a06690ca Eliminate branch and insert an explicit reader memory barrier to ensure
that waiter bit is set before reading semaphore count.
2012-01-16 04:39:10 +00:00
Mikolaj Golub
fe7f89b71a Abrogate nchr argument in proc_getargv() and proc_getenvv(): we always want
to read strings completely to know the actual size.

As a side effect it fixes the issue with kern.proc.args and kern.proc.env
sysctls, which didn't return the size of available data when calling
sysctl(3) with the NULL argument for oldp.

Note, in get_ps_strings(), which does actual work for proc_getargv() and
proc_getenvv(), we still have a safety limit on the size of data read in
case of a corrupted procces stack.

Suggested by:	kib
MFC after:	3 days
2012-01-15 18:47:24 +00:00
Martin Matuska
9cbe30e1d5 Fix missing in r230129:
kern_jail.c: initialize fullpath_disabled to zero
vfs_cache.c: add missing dot in comment

Reported by:	kib
MFC after:	1 month
2012-01-15 18:08:15 +00:00
Ulrich Spörlein
9a14aa017b Convert files to UTF-8 2012-01-15 13:23:18 +00:00
Martin Matuska
f6e633a9e1 Introduce vn_path_to_global_path()
This function updates path string to vnode's full global path and checks
the size of the new path string against the pathlen argument.

In vfs_domount(), sys_unmount() and kern_jail_set() this new function
is used to update the supplied path argument to the respective global path.

Unbreaks jailed zfs(8) with enforce_statfs set to 1.

Reviewed by:	kib
MFC after:	1 month
2012-01-15 12:08:20 +00:00
Eitan Adler
886e862866 - Fix undefined behavior when device_get_name is null
- Make error message more informative

PR:		kern/149800
Submitted by:	olgeni
Approved by:	cperciva
MFC after:	1 week
2012-01-15 07:09:18 +00:00
Oleksandr Tymoshenko
4104e83567 Fix kernel modules loading for MIPS64 kernel:
On amd64, link_elf_obj.c must specify KERNBASE rather than
    VM_MIN_KERNEL_ADDRESS to vm_map_find() because kernel loadable
    modules must be mapped for execution in the same upper region
    of the kernel map as the kernel code and data segments.

    For MIPS32 KERNBASE lies below KVA area (it's less than
    VM_MIN_KERNEL_ADDRESS) so basically vm_map_find got whole
    KVA to look through. On MIPS64 it's not the case because
    KERNBASE is set to the very end of XKSEG, well out of KVA
    bounds, so vm_map_find always fails. We should use
    VM_MIN_KERNEL_ADDRESS as a base for vm_map_find.

Details obtained from: alc@
2012-01-14 00:36:07 +00:00
John Baldwin
fbcebf7f71 Convert the per-interface address list lock from a mutex to a reader/writer
lock.

Reviewed by:	bz
2012-01-09 19:34:12 +00:00
Andriy Gapon
90d8265326 enable stop_scheduler_on_panic by default
My plan is to make this behavior unconditional before 10.0 release.

X-MFC after:	r228424 (if ever)
2012-01-09 12:06:09 +00:00
Konstantin Belousov
3ab0160340 Avoid LOR between vfs_busy() lock and covered vnode lock on quotaon().
The vfs_busy() is after covered vnode lock in the global lock order, but
since quotaon() does recursive VFS call to open quota file, we usually
end up locking covered vnode after mp is busied in sys_quotactl().

Change the interface of VFS_QUOTACTL(), requiring that mp was unbusied
by fs code, and do not try to pick up vfs_busy() reference in ufs quotaon,
esp. if vfs_busy cannot succeed due to unmount being performed.

Reported and tested by:	pho
MFC after:	1 week
2012-01-08 23:06:53 +00:00
Alan Cox
2971897d51 Correct an error of omission in the implementation of the truncation
operation on POSIX shared memory objects and tmpfs.  Previously, neither of
these modules correctly handled the case in which the new size of the object
or file was not a multiple of the page size.  Specifically, they did not
handle partial page truncation of data stored on swap.  As a result, stale
data might later be returned to an application.

Interestingly, a data inconsistency was less likely to occur under tmpfs
than POSIX shared memory objects.  The reason being that a different mistake
by the tmpfs truncation operation helped avoid a data inconsistency.  If the
data was still resident in memory in a PG_CACHED page, then the tmpfs
truncation operation would reactivate that page, zero the truncated portion,
and leave the page pinned in memory.  More precisely, the benevolent error
was that the truncation operation didn't add the reactivated page to any of
the paging queues, effectively pinning the page.  This page would remain
pinned until the file was destroyed or the page was read or written.  With
this change, the page is now added to the inactive queue.

Discussed with:	jhb
Reviewed by:	kib (an earlier version)
MFC after:	3 weeks
2012-01-08 20:09:26 +00:00
Hiroki Sato
ca54e1aee3 Fix a typo. (s/nessesary/necessary/) 2012-01-08 18:48:36 +00:00
John Baldwin
71eeeaf256 Add 5 spare VOPs as placeholders to avoid breaking the KBI in the future
when new VOPs are MFC'd to a branch.

Reviewed by:	kib, bz
MFC after:	3 days
2012-01-06 20:06:45 +00:00
John Baldwin
908cac07ce Use proper argument structure types for the extattr post-VOP hooks.
The wrong structure happened to work since the only argument used was
the vnode which is in the same place in both VOP_SETATTR() and the two
extattr VOPs.

MFC after:	3 days
2012-01-06 20:05:48 +00:00
John Baldwin
948c460971 Fix a logic bug in change 228207 in the check for a thread's new user
priority being a realtime priority.

MFC after:	3 days
2012-01-05 19:02:52 +00:00
John Baldwin
137f91e80f Convert all users of IF_ADDR_LOCK to use new locking macros that specify
either a read lock or write lock.

Reviewed by:	bz
MFC after:	2 weeks
2012-01-05 19:00:36 +00:00
John Baldwin
7e3a96ea37 Some small fixes to CPU accounting for threads:
- Only initialize the per-cpu switchticks and switchtime in sched_throw()
  for the very first context switch on APs during boot.  This avoids a
  small gap between the middle of thread_exit() and sched_throw() where
  time is not accounted to any thread.
- In thread_exit(), update the timestamp bookkeeping to track the changes
  to mi_switch() introduced by td_rux so that the code once again matches
  the comment claiming it is mimicing mi_switch().  Specifically, only
  update the per-thread stats directly and depend on ruxagg() to update
  p_rux rather than adjusting p_rux directly.  While here, move the
  timestamp bookkeeping as late in the function as possible.

Reviewed by:	bde, kib
MFC after:	1 week
2012-01-03 21:03:28 +00:00
Ed Schouten
dc15eac046 Use strchr() and strrchr().
It seems strchr() and strrchr() are used more often than index() and
rindex(). Therefore, simply migrate all kernel code to use it.

For the XFS code, remove an empty line to make the code identical to
the code in the Linux kernel.
2012-01-02 12:12:10 +00:00
Konstantin Belousov
cdb7a43117 Avoid double-unlock or double unreference for ndp->ni_dvp when the vnode dp
lock upgrade right after the 'success' label fails.

In collaboration with:	pho
MFC after:	1 week
2012-01-01 18:45:59 +00:00
John Baldwin
0c0d27d5dd Cap the priority calculated from the current thread's running tick count
at SCHED_PRI_RANGE to prevent overflows in the priority value.  This can
happen due to irregularities with clock interrupts under certain
virtualization environments.

Tested by:	Larry Rosenman  ler lerctr org
MFC after:	2 weeks
2011-12-29 16:17:16 +00:00
Lawrence Stewart
6cedd609b7 Introduce the sysclock_getsnapshot() and sysclock_snap2bintime() KPIs. The
sysclock_getsnapshot() function allows the caller to obtain a snapshot of all
the system clock and timecounter state required to create time stamps at a later
point. The sysclock_snap2bintime() function converts a previously obtained
snapshot into a bintime time stamp according to the specified flags e.g. which
system clock, uptime vs absolute time, etc.

These KPIs enable useful functionality, including direct comparison of the
feedback and feed-forward system clocks and generation of multiple time stamps
with different formats from a single timecounter read.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

In collaboration with:	Julien Ridoux (jridoux at unimelb edu au)
2011-12-24 01:32:01 +00:00
John Baldwin
f0d6c5caf0 Add post-VOP hooks for VOP_DELETEEXTATTR() and VOP_SETEXTATTR() and use
these to trigger a NOTE_ATTRIB EVFILT_VNODE kevent when the extended
attributes of a vnode are changed.

Note that OS X already implements this behavior.

Reviewed by:	rwatson
MFC after:	2 weeks
2011-12-23 20:11:37 +00:00
John Baldwin
268e76d86e Use TASK_INITIALIZER() for dev_dtr_task rather than a dedicated SYSINIT(). 2011-12-22 16:01:10 +00:00
Andriy Gapon
167057914b ule: ensure that batch timeshare threads are scheduled fairly
With the previous code, if the range of priorities for timeshare batch
threads was greater than RQ_NQS, then the threads with low priorities in
the part of the range above RQ_NQS would be scheduled to the run-queues
as if they had high priorities at the beginning of the range.
In other words, threads with a nice level of +N could be scheduled as
if they had a nice level of -M.

Reported by:	George Mitchell <george@m5p.com>
Reviewed by:	jhb
Tested by:	George Mitchell <george@m5p.com> (earlier version)
MFC after:	1 week
2011-12-19 20:01:21 +00:00
Mikolaj Golub
547b155eb1 Fix style and white spaces.
MFC after:	1 week
2011-12-17 22:18:26 +00:00
Mikolaj Golub
fa3935bcea On start most of sysctl_kern_proc functions use the same pattern:
locate a process calling pfind() and do some additional checks like
p_candebug(). To reduce this code duplication a new function pget() is
introduced and used.

As the function may be useful not only in kern_proc.c it is in the
kernel name space.

Suggested by:	kib
Reviewed by:	kib
MFC after:	2 weeks
2011-12-17 16:59:22 +00:00
Andriy Gapon
f389bc9585 belatedly transfer copyrights from libkern/gets.c to kern_cons.c
MFC after:	2 months
MFC with:	r228642
2011-12-17 15:50:45 +00:00
Andriy Gapon
f6ce353e58 replace uses of libkern gets with cngets
MFC after:	2 months
2011-12-17 15:26:34 +00:00
Andriy Gapon
8e62854265 introduce cngets, a method for kernel to read a string from console
This is intended as a replacement for libkern's gets and mostly borrows
its implementation.  It uses cngrab/cnungrab to delimit kernel's access
to console input.

Note: libkern's gets obviously doesn't share any bits of implementation
iwth libc's gets.  They also have different APIs and the former doesn't
have the overflow problems of the latter.

Inspired by:	bde
MFC after:	2 months
2011-12-17 15:16:54 +00:00
Andriy Gapon
bf8696b408 introduce cngrab/cnungrab stub calls in some places where they make sense
MFC after:	2 months
2011-12-17 15:11:22 +00:00
Andriy Gapon
9976156f12 kern cons: introduce infrastructure for console grabbing by kernel
At the moment grab and ungrab methods of all console drivers are no-ops.

Current intended meaning of the calls is that the kernel takes control of
console input.  In the future the semantics may be extended to mean that
the calling thread takes full ownership of the console (e.g. console
output from other threads could be suspended).

Inspired by:	bde
MFC after:	2 months
2011-12-17 15:08:43 +00:00
John Baldwin
f427c78b19 Fire a kevent if necessary after seeking on a regular file. This fixes a
case where a kevent would not fire on a regular file if an application read
to EOF and then seeked backwards into the file.

Reviewed by:	kib
MFC after:	2 weeks
2011-12-16 20:10:00 +00:00
John Baldwin
338e7cf235 Use vm_mmap_to_errno().
Submitted by:	kib
2011-12-15 15:17:19 +00:00
Jilles Tjoelker
6d1c58f8a2 Fix select/poll/kqueue for write on reverse direction before first write.
The reverse direction of a pipe is lazily allocated on the first write in
that direction (because pipes are usually used in one direction only).  A
special case is needed to ensure the pipe appears writable before the first
write because there are 0 bytes of pending data in 0 bytes of buffer space
at that point, leaving 0 bytes of data that can be written with the normal
code.

Note that the first write returns [ENOMEM] if kern.ipc.maxpipekva is
exceeded and does not block or return [EAGAIN], so selecting true for write
is correct even in that case.

PR:		kern/93685
Submitted by:	gianni
MFC after:	2 weeks
2011-12-14 22:26:39 +00:00
John Baldwin
fb680e16f4 Add a helper API to allow in-kernel code to map portions of shared memory
objects created by shm_open(2) into the kernel's address space.  This
provides a convenient way for creating shared memory buffers between
userland and the kernel without requiring custom character devices.
2011-12-14 22:22:19 +00:00
David E. O'Brien
1c5151f3f8 Match other formatting. 2011-12-14 02:31:32 +00:00
David E. O'Brien
3d7618d8bf Disallow various debug.kdb sysctl's when securelevel is raised.
PR:	161350
2011-12-13 17:59:16 +00:00
Eitan Adler
9910b854c6 - Add a sysctl to allow non-root users the ability to set idle
priorities.

- While here fix up some style nits.

Discussed with: cperciva (breifly)
Reviewed by:	pjd (earlier version)
Reviewed by:	bde
Approved by:	jhb
MFC after:	1 month
2011-12-13 14:00:27 +00:00
Eitan Adler
3eb9ab5255 Document a large number of currently undocumented sysctls. While here
fix some style(9) issues and reduce redundancy.

PR:		kern/155491
PR:		kern/155490
PR:		kern/155489
Submitted by:	Galimov Albert <wtfcrap@mail.ru>
Approved by:	bde
Reviewed by:	jhb
MFC after:	1 week
2011-12-13 00:38:50 +00:00
Andriy Gapon
7a7ce668ef put sys/systm.h at its proper place or add it if missing
Reported by:	lstewart, tinderbox
Pointyhat to:	avg, attilio
MFC after:	1 week
MFC with:	r228430
2011-12-12 10:05:13 +00:00
Andriy Gapon
0e225211a0 kern_racct: move sys/systm.h inclusion to its proper place
This should fix the build failure introduced with r228424.
Also remove duplicate inclusion of sys/param.h.

Pointyhat to:	avg
MFC after:	1 week
2011-12-12 07:46:10 +00:00
Andriy Gapon
353705930f panic: add a switch and infrastructure for stopping other CPUs in SMP case
Historical behavior of letting other CPUs merily go on is a default for
time being.  The new behavior can be switched on via
kern.stop_scheduler_on_panic tunable and sysctl.

Stopping of the CPUs has (at least) the following benefits:
- more of the system state at panic time is preserved intact
- threads and interrupts do not interfere with dumping of the system
  state

Only one thread runs uninterrupted after panic if stop_scheduler_on_panic
is set.  That thread might call code that is also used in normal context
and that code might use locks to prevent concurrent execution of certain
parts.  Those locks might be held by the stopped threads and would never
be released.  To work around this issue, it was decided that instead of
explicit checks for panic context, we would rather put those checks
inside the locking primitives.

This change has substantial portions written and re-written by attilio
and kib at various times.  Other changes are heavily based on the ideas
and patches submitted by jhb and mdf.  bde has provided many insights
into the details and history of the current code.

The new behavior may cause problems for systems that use a USB keyboard
for interfacing with system console.  This is because of some unusual
locking patterns in the ukbd code which have to be used because on one
hand ukbd is below syscons, but on the other hand it has to interface
with other usb code that uses regular mutexes/Giant for its concurrency
protection.  Dumping to USB-connected disks may also be affected.

PR:			amd64/139614 (at least)
In cooperation with:	attilio, jhb, kib, mdf
Discussed with:		arch@, bde
Tested by:		Eugene Grosbein <eugen@grosbein.net>,
			gnn,
			Steven Hartland <killing@multiplay.co.uk>,
			glebius,
			Andrew Boyer <aboyer@averesystems.com>
			(various versions of the patch)
MFC after:		3 months (or never)
2011-12-11 21:02:01 +00:00
Peter Holm
cdea31e305 Move cpu_set_upcall(newtd, td) up before the first call of
thread_free(newtd).  This to avoid a possible page fault in
cpu_thread_clean() as seen on amd64 with syscall fuzzing.

Reviewed by:	kib
MFC after:	1 week
2011-12-09 17:19:41 +00:00
Eitan Adler
5a01b72672 - Fix ktrace leakage if error is set
PR:		kern/163098
Submitted by:	Loganaden Velvindron <loganaden@devio.us>
Approved by:	sbruno@
MFC after:	1 month
2011-12-08 03:20:38 +00:00
Alan Cox
ea3f07d3a0 Eliminate stale numbers from a comment. 2011-12-07 16:27:23 +00:00
Alan Cox
c749c003b8 Eliminate the possibility of 32-bit arithmetic overflow in the calculation
of vm_kmem_size that may occur if the system administrator has specified a
vm.vm_kmem_size tunable value that exceeds the hard cap.

PR:		162741
Submitted by:	Adam McDougall
Reviewed by:	bde@
MFC after:	3 weeks
2011-12-07 07:03:14 +00:00
Konstantin Belousov
93c26de0ad Most users of pipe(2) do not call fstat(2) on the returned pipe descriptors.
Optimize for the case, by lazily allocating the pipe inode number at the
fstat(2) time. If alloc_unr(9) returns failure, do not fail fstat(2), since
uses of inode numbers are even rare then fstat(2), but provide zero inode
forever. Note that alloc_unr() failure is unlikely due to total number
of pipes in the system limited by the number of file descriptors.

Based on the submission by:	gianni
MFC after:	2 weeks
2011-12-06 11:24:03 +00:00
Mikolaj Golub
9e94d5b83f Really protect kern.proc.ps_strings sysctls with p_candebug(). This
was intended to be in r228288.

Spotted by:	many
MFC after:	1 week
2011-12-06 06:40:14 +00:00
Mikolaj Golub
c65932be9d Protect kern.proc.auxv and kern.proc.ps_strings sysctls with p_candebug().
Citing jilles:

If we are ever going to do ASLR, the AUXV information tells an attacker
where the stack, executable and RTLD are located, which defeats much of
the point of randomizing the addresses in the first place.

Given that the AUXV information seems to be used by debuggers only anyway,
I think it would be good to move it to p_candebug() now.

The full virtual memory maps (KERN_PROC_VMMAP, procstat -v) are already
under p_candebug().

Suggested by:	jilles
Discussed with:	rwatson
MFC after:	1 week
2011-12-05 19:34:02 +00:00
Kevin Lo
2b69bb1f27 Add a missing curly bracket 2011-12-05 10:34:52 +00:00
Andriy Gapon
5e27a60372 critical_exit: ignore td_owepreempt if kdb_active is set
calling mi_switch in such a context results in a recursion via
kdb_switch

Suggested by:	jhb
Reviewed by:	jhb
MFC after:	5 weeks
2011-12-04 21:27:41 +00:00
Mikolaj Golub
0f60ecdaa4 In sysctl_kern_proc_ps_strings() there is no much sense in checking
for P_WEXIT and P_SYSTEM flags.

Reviewed by:	kib
2011-12-04 21:24:01 +00:00
Hans Petter Selasky
494b6fec82 Make sure the description of pause() is
equivalent to its implementation.
No code change.

Suggested by:	Bruce Evans
MFC after:	3 days
2011-12-03 15:51:15 +00:00
Eitan Adler
f565f395c6 - Fix typos s/(more|less) then|\1 than/
Submitted by:	Davide Italiano <davide.italiano@gmail.com>
Approved by:	brucec
MFC after:	3 days
2011-12-03 15:41:37 +00:00
Peter Holm
9a1d0cf68f Use umtx_copyin_timeout() to copy and check timeout parameter.
In collaboration with:	kib
MFC after:	1 week
2011-12-03 12:35:13 +00:00
Peter Holm
662ebe9b53 Add umtx_copyin_timeout() and move parameter checks here.
In collaboration with:	kib
MFC after:	1 week
2011-12-03 12:30:58 +00:00
Peter Holm
ff77dfb0c1 Rename copyin_timeout32 to umtx_copyin_timeout32 and move parameter
check here. Include check for negative seconds value.

In collaboration with:	kib
MFC after:	1 week
2011-12-03 12:28:33 +00:00
Marius Strobl
002214d6bb It doesn't make much sense to check whether child is NULL after already
having dereferenced it. We either should generally check the device_t's
supplied to bus functions before using them (which we seem to virtually
never do) or just assume that they are not NULL.
While at it make this code fit 78 columns.

Found with:	Coverity Prevent(tm)
CID:		4230
2011-12-02 22:03:27 +00:00
Marius Strobl
f60d6c2bdf - In device_probe_child(9) check the return value of device_set_driver(9)
when actually setting a driver as especially ENOMEM is fatal in these
  cases.
- Annotate other calls to device_set_devclass(9) and device_set_driver(9)
  without the return value being checked and that are okay to fail.

Reviewed by:	yongari (slightly earlier version)
2011-12-02 21:19:14 +00:00
John Baldwin
593dd43eee When changing the user priority of a thread, change the real priority
in addition to the user priority for threads whose current real priority
is equal to the previous user priority or if the new priority is a
real-time priority.  This allows priority changes of other threads to
have an immediate effect.

MFC after:	2 weeks
2011-12-02 19:59:46 +00:00
Konstantin Belousov
5ed954efd1 If alloc_unr() call in the pipe_create() failed, then pipe->pipe_ino is
-1. But, because ino_t is unsigned, this case was not covered by the
test ino > 0 in pipeclose(), leading to the free_unr(-1). Fix it by
explicitely comparing with 0 and -1. [1]

Do no access freed memory, the inode number was cached to prevent access
to cpipe after it possibly was freed, but I failed to commit the right
patch.

Noted by:	gianni [1]
Pointy hat to:	kib
MFC after:	3 days
2011-12-01 11:36:41 +00:00
Lawrence Stewart
66dcfed32a Revise the sysctl handling code and restructure the hierarchy of sysctls
introduced when feed-forward clock support is enabled in the kernel:

- Rename the "choice" variable to "available".

- Streamline the implementation of the "active" variable's sysctl handler
  function.

- Create a kern.sysclock sysctl node for general sysclock related configuration
  options. Place the "available" and "active" variables under this node.

- Create a kern.sysclock.ffclock sysctl node for feed-forward clock specific
  configuration options. Place the "version" and "ffcounter_bypass" variables
  under this node.

- Tweak some of the description strings.

Discussed with:	Julien Ridoux (jridoux at unimelb edu au)
2011-12-01 07:19:13 +00:00
Konstantin Belousov
dc874f9881 Rename vm_page_set_valid() to vm_page_set_valid_range().
The vm_page_set_valid() is the most reasonable name for the m->valid
accessor.

Reviewed by:	attilio, alc
2011-11-30 17:39:00 +00:00
Lawrence Stewart
6f83fc5112 Make sysclock_active publicly available to external consumers.
Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Discussed with:	Julien Ridoux (jridoux at unimelb edu au)
Submitted by:	Julien Ridoux (jridoux at unimelb edu au)
2011-11-29 08:43:04 +00:00
Lawrence Stewart
88394fe42c Do away with the somewhat clunky sysclock_ops structure and associated code,
reimplementing the [get]{bin,nano,micro}[up]time() wrapper functions in terms of
the new "fromclock" API instead.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Discussed with:	Julien Ridoux (jridoux at unimelb edu au)
Submitted by:	Julien Ridoux (jridoux at unimelb edu au)
2011-11-29 08:33:40 +00:00
Lawrence Stewart
e977bac333 Make the fbclock_[get]{bin,nano,micro}[up]time() function prototypes public so
that new APIs with some performance sensitivity can be built on top of them.
These functions should not be called directly except in special circumstances.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Discussed with:	Julien Ridoux (jridoux at unimelb edu au)
Submitted by:	Julien Ridoux (jridoux at unimelb edu au)
2011-11-29 06:53:36 +00:00
Lawrence Stewart
c2a4ee9906 Fix an oversight in r227747 by calling fbclock_bin{up}time() directly from the
fbclock_{nanouptime|microuptime|bintime|nanotime|microtime}() functions to avoid
indirecting through a sysclock_ops wrapper function.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Submitted by:	Julien Ridoux (jridoux at unimelb edu au)
2011-11-29 06:12:19 +00:00
Mikolaj Golub
9732458f35 Add sysctl to retrieve ps_strings structure location of another process.
Suggested by:	kib
Reviewed by:	kib
2011-11-27 17:05:26 +00:00
Mikolaj Golub
4fd6053b43 In sysctl_kern_proc_auxv the process was released too early: we still
need to hold it when checking process sv_flags.

MFC after:	2 weeks
2011-11-27 16:56:01 +00:00
Lawrence Stewart
66761af34f Export the "ffclock" feature for kernels compiled with feed-forward clock
support.

Suggested by:	netchild
Reviewed by:	netchild
2011-11-26 01:44:37 +00:00
Mikolaj Golub
9e7d058351 Add sysctl to get process resource limits.
Reviewed by:	kib
MFC after:	2 weeks
2011-11-24 20:43:37 +00:00
Konstantin Belousov
561984be06 Fix a race between getvnode() dereferencing half-constructed file
and dupfdopen().

Reported and tested by:	pho
MFC after:	3 days
2011-11-24 20:34:06 +00:00
Mikolaj Golub
7ad9baae41 Fix build without INVARIANTS.
Discussed with:	kib
2011-11-23 08:11:04 +00:00
Hans Petter Selasky
3b12bdb58f Rename device_delete_all_children() into device_delete_children().
Suggested by:	jhb @ and marius @
MFC after:	1 week
2011-11-22 21:56:55 +00:00
Hans Petter Selasky
5b288d2abf Style change.
Suggested by:	jhb @ and marius @
MFC after:	1 week
2011-11-22 21:53:19 +00:00
Mikolaj Golub
c5cfcb1c19 Add new sysctls, KERN_PROC_ENV and KERN_PROC_AUXV, to return
environment strings and ELF auxiliary vectors from a process stack.

Make sysctl_kern_proc_args to read not cached arguments from the
process stack.

Export proc_getargv() and proc_getenvv() so they can be reused by
procfs and linprocfs.

Suggested by:	kib
Reviewed by:	kib
Discussed with:	kib, rwatson, jilles
Tested by:	pho
MFC after:	2 weeks
2011-11-22 20:40:18 +00:00
Lawrence Stewart
65e359a15c - Add Pulse-Per-Second timestamping using raw ffcounter and corresponding
ffclock time in seconds.

- Add IOCTL to retrieve ffclock timestamps from userland.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Submitted by:	Julien Ridoux (jridoux at unimelb edu au)
2011-11-21 13:34:29 +00:00
Attilio Rao
9fde98bba3 Introduce the same mutex-wise fix in r227758 for sx locks.
The functions that offer file and line specifications are:
- sx_assert_
- sx_downgrade_
- sx_slock_
- sx_slock_sig_
- sx_sunlock_
- sx_try_slock_
- sx_try_xlock_
- sx_try_upgrade_
- sx_unlock_
- sx_xlock_
- sx_xlock_sig_
- sx_xunlock_

Now vm_map locking is fully converted and can avoid to know specifics
about locking procedures.
Reviewed by:	kib
MFC after:	1 month
2011-11-21 12:59:52 +00:00
Sergey Kandaurov
ca4aa8c363 Remove no more relevant XXXRW comments since accessing the vmspace is now
properly done with the acquired vmspace reference.

Pointed out by:		kib
2011-11-21 12:21:00 +00:00
Sergey Kandaurov
18be8527e9 Use the acquired reference to the vmspace instead of direct dereferencing
of p->p_vmspace like it is done in sysctl_kern_proc_vmmap().
2011-11-21 10:36:57 +00:00
Lawrence Stewart
cf13a58510 - Add the ffclock_getcounter(), ffclock_getestimate() and ffclock_setestimate()
system calls to provide feed-forward clock management capabilities to
  userspace processes. ffclock_getcounter() returns the current value of the
  kernel's feed-forward clock counter. ffclock_getestimate() returns the current
  feed-forward clock parameter estimates and ffclock_setestimate() updates the
  feed-forward clock parameter estimates.

- Document the syscalls in the ffclock.2 man page.

- Regenerate the script-derived syscall related files.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Submitted by:	Julien Ridoux (jridoux at unimelb edu au)
2011-11-21 01:26:10 +00:00
Attilio Rao
ccdf233323 Introduce macro stubs in the mutex implementation that will be always
defined and will allow consumers, willing to provide options, file and
line to locking requests, to not worry about options redefining the
interfaces.
This is typically useful when there is the need to build another
locking interface on top of the mutex one.

The introduced functions that consumers can use are:
- mtx_lock_flags_
- mtx_unlock_flags_
- mtx_lock_spin_flags_
- mtx_unlock_spin_flags_
- mtx_assert_
- thread_lock_flags_

Spare notes:
- Likely we can get rid of all the 'INVARIANTS' specification in the
  ppbus code by using the same macro as done in this patch (but this is
  left to the ppbus maintainer)
- all the other locking interfaces may require a similar cleanup, where
  the most notable case is sx which will allow a further cleanup of
  vm_map locking facilities
- The patch should be fully compatible with older branches, thus a MFC
  is previewed (infact it uses all the underlying mechanisms already
  present).

Comments review by:	eadler, Ben Kaduk
Discussed with:		kib, jhb
MFC after:	1 month
2011-11-20 16:33:09 +00:00
Hans Petter Selasky
9e3ae31c7a Given that the typical usage of pause() is pause("zzz", hz / N), where N can
be greater than hz in some cases, simply ignore a timeout value of zero.

Suggested by:	Bruce Evans
MFC after:	1 week
2011-11-20 08:36:18 +00:00
Hans Petter Selasky
f1a1612fc2 Minor style change:
Simplify the description of pause() and shorten the KASSERT message in pause.
Also add a clamp for the timo argument in the non-KASSERT case.

Suggested by:	Bruce Evans
MFC after:	1 week
2011-11-20 08:29:23 +00:00
Lawrence Stewart
9bce0f05fe - Provide a sysctl interface to change the active system clock at runtime.
- Wrap [get]{bin,nano,micro}[up]time() functions of sys/time.h to allow
  requesting time from either the feedback or the feed-forward clock. If a
  feedback (e.g. ntpd) and feed-forward (e.g. radclock) daemon are both running
  on the system, both kernel clocks are updated but only one serves time.

- Add similar wrappers for the feed-forward difference clock.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Submitted by:	Julien Ridoux (jridoux at unimelb edu au)
2011-11-20 05:32:12 +00:00
Lawrence Stewart
f464c5ccb5 Provide high-level functions to access the feed-forward absolute and difference
clocks. Each routine can output an upper bound on the absolute time or time
interval requested. Different flavours of absolute time can be requested, for
example with or without leap seconds, monotonic or not, etc.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Submitted by:	Julien Ridoux (jridoux at unimelb edu au)
2011-11-20 01:20:50 +00:00
Lawrence Stewart
b0fdc83713 Core structure and functions to support a feed-forward clock within the kernel.
Implement ffcounter, a monotonically increasing cumulative counter on top of the
active timecounter. Provide low-level functions to read the ffcounter and
convert it to absolute time or a time interval in seconds using the current
ffclock estimates, which track the drift of the oscillator. Add a ring of
fftimehands to track passing of time on each kernel tick and pick up updates of
ffclock estimates.

Committed on behalf of Julien Ridoux and Darryl Veitch from the University of
Melbourne, Australia, as part of the FreeBSD Foundation funded "Feed-Forward
Clock Synchronization Algorithms" project.

For more information, see http://www.synclab.org/radclock/

Submitted by:	Julien Ridoux (jridoux at unimelb edu au)
2011-11-19 14:10:16 +00:00
Hans Petter Selasky
3ddd1777d5 Simplify the usb_pause_mtx() function by factoring out the generic parts
to the kernel's pause() function. The pause() function can now be used
when cold != 0. Also assert that the timeout in system ticks must be
positive.

Suggested by:	Bruce Evans
MFC after:	1 week
2011-11-19 11:17:27 +00:00
Hans Petter Selasky
11bcf702f4 Move the device_delete_all_children() function from usb_util.c
to kern/subr_bus.c. Simplify this function so that it no longer
depends on malloc() to execute. Identify a few other places where
it makes sense to use device_delete_all_children().

MFC after:	1 week
2011-11-19 10:11:50 +00:00
Konstantin Belousov
f82360acf2 Existing VOP_VPTOCNP() interface has a fatal flow that is critical for
nullfs.  The problem is that resulting vnode is only required to be
held on return from the successfull call to vop, instead of being
referenced.

Nullfs VOP_INACTIVE() method reclaims the vnode, which in combination
with the VOP_VPTOCNP() interface means that the directory vnode
returned from VOP_VPTOCNP() is reclaimed in advance, causing
vn_fullpath() to error with EBADF or like.

Change the interface for VOP_VPTOCNP(), now the dvp must be
referenced. Convert all in-tree implementations of VOP_VPTOCNP(),
which is trivial, because vhold(9) and vref(9) are similar in the
locking prerequisites. Out-of-tree fs implementation of VOP_VPTOCNP(),
if any, should have no trouble with the fix.

Tested by:	pho
Reviewed by:	mckusick
MFC after:	3 weeks (subject of re approval)
2011-11-19 07:50:49 +00:00
Ed Schouten
51cfb9474f Regenerate system call tables. 2011-11-19 06:36:11 +00:00
Ed Schouten
d3a993d46b Improve *access*() parameter name consistency.
The current code mixes the use of `flags' and `mode'. This is a bit
confusing, since the faccessat() function as a `flag' parameter to store
the AT_ flag.

Make this less confusing by using the same name as used in the POSIX
specification -- `amode'.
2011-11-19 06:35:15 +00:00
Navdeep Parhar
059d10c7b6 Do not increment the parent firmware's reference count when any other
firmware image in the module is registered.  Instead, do it when the
other image is itself referenced.

This allows a module with multiple firmware images to be automatically
unloaded when none of the firmware images are in use.

Discussed with:	jhb@ (on -hackers)
2011-11-19 00:20:28 +00:00
Peter Holm
7bbcd22d38 Added check for negative seconds value. Found by syscall() fuzzing.
MFC after:	1 week
2011-11-18 19:14:42 +00:00
Konstantin Belousov
7b5190779b Consistently use process spin lock for protection of the
p->p_boundary_count. Race could cause the execve(2) from the threaded
process to hung since thread boundary counter was incorrect and
single-threading never finished.

Reported by:	pluknet, pho
Tested by:	pho
MFC after:	1 week
2011-11-18 09:12:26 +00:00
Kevin Lo
41f1dccceb Add unicode support to msdosfs and smbfs; original pathes from imura,
bug fixes by Kuan-Chung Chiu <buganini at gmail dot com>.

Tested by me in production for several days at work.
2011-11-18 03:05:20 +00:00
Pawel Jakub Dawidek
d576deedb5 Constify arguments for locking KPIs where possible.
This enables locking consumers to pass their own structures around as const and
be able to assert locks embedded into those structures.

Reviewed by:	ed, kib, jhb
2011-11-16 21:51:17 +00:00
Pawel Jakub Dawidek
a20358302f Constify stack argument for functions that don't modify it.
Reviewed by:	ed, kib, jhb
2011-11-16 19:06:55 +00:00
Marius Strobl
d7ecd801ed As it turns out, r186347 actually is insufficient to avoid the use of the
curthread-accessing part of mtx_{,un}lock(9) when using a r210623-style
curthread implementation on sparc64, crashing the kernel in its early
cycles as PCPU isn't set up, yet (and can't be set up as OFW is one of the
things we need for that, which leads to a chicken-and-egg problem). What
happens is that due to the fact that the idea of r210623 actually is to
allow the compiler to cache invocations of curthread, it factors out
obtaining curthread needed for both mtx_lock(9) and mtx_unlock(9) to
before the branch based on kobj_mutex_inited when compiling the kernel
without the debugging options. So change kobj_class_compile_static(9)
to just never acquire kobj_mtx, effectively restricting it to its
documented use, and add a kobj_init_static(9) for initializing objects
using a class compiled with the former and that also avoids using mutex(9)
(and malloc(9)). Also assert in both of these functions that they are
used in their intended way only.
While at it, inline kobj_register_method() and kobj_unregister_method()
as there wasn't much point for factoring them out in the first place
and so that a reader of the code has to figure out the locking for
fewer functions missing a KOBJ_ASSERT.
Tested on powerpc{,64} by andreast.

Reviewed by:	nwhitehorn (earlier version), jhb
MFC after:	3 days
2011-11-15 20:11:03 +00:00
David E. O'Brien
0e31b3c15f Reformat comment to be more readable in standard Xterm.
(while I'm here, wrap other long lines)
2011-11-15 01:48:53 +00:00
Robert Millan
ea4d9a14f1 Remove a few bits of FreeBSD 2.x compatibility code.
Approved by:	kib (mentor)
2011-11-14 18:21:27 +00:00
John Baldwin
7edec6214e - Split out a kern_posix_fadvise() from the posix_fadvise() system call so
it can be used by in-kernel consumers.
- Make kern_posix_fallocate() public.
- Use kern_posix_fadvise() and kern_posix_fallocate() to implement the
  freebsd32 wrappers for the two system calls.
2011-11-14 18:00:15 +00:00
Alfred Perlstein
cfb09e00e6 Constify args to copyiniov and copyinuio. 2011-11-14 07:12:10 +00:00
Konstantin Belousov
56be1b9a7a To limit amount of the kernel memory allocated, and to optimize the
iteration over the fdsets, kern_select() limits the length of the
fdsets copied in by the last valid file descriptor index. If any bit
is set in a mask above the limit, current implementation ignores the
filedescriptor, instead of returning EBADF.

Fix the issue by scanning the tails of fdset before entering the
select loop and returning EBADF if any bit above last valid
filedescriptor index is set. The performance impact of the additional
check is only imposed on the (somewhat) buggy applications that pass
bad file descriptors to select(2) or pselect(2).

PR:	kern/155606, kern/162379
Discussed with:	cognet, glebius
Tested by:	andreast (powerpc, all 64/32bit ABI combinations, big-endian),
       marius (sparc64, big-endian)
MFC after:    2 weeks
2011-11-13 10:28:01 +00:00
Konstantin Belousov
4d651f4e5f Style.
MFC after:	1 week
2011-11-11 04:13:47 +00:00
Konstantin Belousov
f403cfb19c Guard against the unlikely case of the alias path containing the '%' symbols.
Reported by:	arundel
MFC after:	1 week
2011-11-11 04:12:58 +00:00
Ryan Stone
493b584dbd Correct the types of the arguments to return probes of the syscall
provider.  Previously we were erroneously supplying the argument types of
the corresponding entry probe.

Reviewed by:	rpaulo
MFC after:	1 week
2011-11-11 03:49:42 +00:00
Ed Schouten
d09ebcec17 Simplify the code emitted by makeobjops.awk slightly.
Just place the default kobj_method inside the kobjop_desc structure.
There's no need to give these kobj_methods their own symbol. This shaves
off 10 KB of a GENERIC kernel binary.
2011-11-09 11:00:29 +00:00
Ed Schouten
3f3f6bc302 Make kobj_methods constant.
These structures hold no information that is modified during runtime. By
marking this constant, we see approximately 600 symbols become
read-only (amd64 GENERIC). While there, also mark the kobj_method
structures generated by makeobjops.awk static. They are only referenced
by the kobjop_desc structures within the same file.

Before:

	$ ls -l kernel
	-rwxr-xr-x  1 ed  wheel  15937309 Nov  8 16:29 kernel*
	$ size kernel
	    text    data     bss      dec    hex filename
	12260854 1358468 2848832 16468154 fb48ba kernel
	$ nm kernel | fgrep -c ' r '
	8240

After:

	$ ls -l kernel
	-rwxr-xr-x  1 ed  wheel  15922469 Nov  8 16:25 kernel*
	$ size kernel
	    text    data     bss      dec    hex filename
	12302869 1302660 2848704 16454233 fb1259 kernel
	$ nm kernel | fgrep -c ' r '
	8838
2011-11-08 15:38:21 +00:00
Ryan Stone
6f6924e5a6 The in-kernel CTF parser caches the result of its first attempt to parse
CTF data from a module.  On subsequent attempts to retrieve CTF data for
a module, return an error if there no CTF data.

This fixes a panic if you try to enable fbt probes on a module with CTF
data twice.

Submitted by:	Paul Ambrose (ambrosehua AT gmail DOT com)
MFC after:	3 days
2011-11-08 15:17:54 +00:00
Attilio Rao
ed1f6dc235 Introduce the option VFS_ALLOW_NONMPSAFE and turn it on by default on
all the architectures.
The option allows to mount non-MPSAFE filesystem. Without it, the
kernel will refuse to mount a non-MPSAFE filesytem.

This patch is part of the effort of killing non-MPSAFE filesystems
from the tree.

No MFC is expected for this patch.

Tested by:	gianni
Reviewed by:	kib
2011-11-08 10:18:07 +00:00
Mikolaj Golub
5384d08913 Add KVME_FLAG_SUPER and use it in sysctl_kern_proc_vmmap for marking
entries with superpages.

Submitted by:	Mel Flynn <mel.flynn+fbsd.hackers@mailing.thruhere.net>
Reviewed by:	alc, rwatson
2011-11-07 21:13:19 +00:00
Mikolaj Golub
bde886fba4 In lim_fork() assert that processes locks are held.
Suggested by:	kib
2011-11-07 21:09:04 +00:00
Ed Schouten
6472ac3d8a Mark all SYSCTL_NODEs static that have no corresponding SYSCTL_DECLs.
The SYSCTL_NODE macro defines a list that stores all child-elements of
that node. If there's no SYSCTL_DECL macro anywhere else, there's no
reason why it shouldn't be static.
2011-11-07 15:43:11 +00:00
Ed Schouten
d745c852be Mark MALLOC_DEFINEs static that have no corresponding MALLOC_DECLAREs.
This means that their use is restricted to a single C file.
2011-11-07 06:44:47 +00:00
Max Khon
4e313b699e Add KLD_DEBUG option. 2011-11-06 08:10:41 +00:00
John Baldwin
cd06ae5c1b Regen. 2011-11-04 04:06:31 +00:00
John Baldwin
936c09ac0f Add the posix_fadvise(2) system call. It is somewhat similar to
madvise(2) except that it operates on a file descriptor instead of a
memory region.  It is currently only supported on regular files.

Just as with madvise(2), the advice given to posix_fadvise(2) can be
divided into two types.  The first type provide hints about data access
patterns and are used in the file read and write routines to modify the
I/O flags passed down to VOP_READ() and VOP_WRITE().  These modes are
thus filesystem independent.  Note that to ease implementation (and
since this API is only advisory anyway), only a single non-normal
range is allowed per file descriptor.

The second type of hints are used to hint to the OS that data will or
will not be used.  These hints are implemented via a new VOP_ADVISE().
A default implementation is provided which does nothing for the WILLNEED
request and attempts to move any clean pages to the cache page queue for
the DONTNEED request.  This latter case required two other changes.
First, a new V_CLEANONLY flag was added to vinvalbuf().  This requests
vinvalbuf() to only flush clean buffers for the vnode from the buffer
cache and to not remove any backing pages from the vnode.  This is
used to ensure clean pages are not wired into the buffer cache before
attempting to move them to the cache page queue.  The second change adds
a new vm_object_page_cache() method.  This method is somewhat similar to
vm_object_page_remove() except that instead of freeing each page in the
specified range, it attempts to move clean pages to the cache queue if
possible.

To preserve the ABI of struct file, the f_cdevpriv pointer is now reused
in a union to point to the currently active advice region if one is
present for regular files.

Reviewed by:	jilles, kib, arch@
Approved by:	re (kib)
MFC after:	1 month
2011-11-04 04:02:50 +00:00
John Baldwin
dccc45e4c0 Move the cleanup of f_cdevpriv when the reference count of a devfs
file descriptor drops to zero out of _fdrop() and into devfs_close_f()
as it is only relevant for devfs file descriptors.

Reviewed by:	kib
MFC after:	1 week
2011-11-04 03:39:31 +00:00
Attilio Rao
2b10b1f872 Disable interrupt and preemption for smp_rendezvous() also in the
UP/!SMP case.
The callbacks may be relying on this feature and having 2 different
ways to deal with them is not correct.

Reported by:	rstone
Reviewed by:	jhb
MFC after:	2 weeks
2011-11-03 14:36:56 +00:00
Marcel Moolenaar
b2f1a8f2b3 Revert rev. 226893: subr_syscall.c is being included from C files and
on amd64 with FREEBSD32 enabled, this means that systrace_probe_func
gets defined twice.
2011-10-30 02:19:39 +00:00
Marcel Moolenaar
056f0ec755 Define systrace_probe_func in subr_syscall.c where it's used, instead
of defining it in MD code. This eliminates porting to other architectures.
2011-10-29 01:26:36 +00:00
Sergey Kandaurov
c241c5e49a Fix arguments list for proc:::signal-discard DTrace probe.
Reported by:	Anton Yuzhaninov <citrin citrin ru>
MFC after:	1 week
2011-10-28 15:22:51 +00:00
John Baldwin
62238a6791 Whitespace fix. 2011-10-27 17:43:36 +00:00
Alan Cox
703dec68bf Eliminate vestiges of page coloring in VM_ALLOC_NOOBJ calls to
vm_page_alloc().  While I'm here, for the sake of consistency, always
specify the allocation class, such as VM_ALLOC_NORMAL, as the first of
the flags.
2011-10-27 16:39:17 +00:00
Sergey Kandaurov
3bedc94069 Remove the long reprecated ``/stand/sysinstall'' from the init_path.
It can be put back using the INIT_PATH config option or init_path
loader variable, if still needed (which I doubt).

MFC after:	1 week
2011-10-27 10:25:11 +00:00
Alan Cox
f346986b76 contigmalloc(9) and contigfree(9) are now implemented in terms of other
more general VM system interfaces.  So, their implementation can now
reside in kern_malloc.c alongside the other functions that are declared
in malloc.h.
2011-10-27 02:52:24 +00:00
John Baldwin
c48fb4da4c - Fixup filenames in a few more places where they are used.
- Some whitespace fixes.
2011-10-26 15:17:42 +00:00
Pawel Jakub Dawidek
4c11f091df The v_data field is a pointer, so set it to NULL, not 0.
MFC after:	3 days
2011-10-25 14:01:17 +00:00
Marcel Moolenaar
421b7fe574 Don't terminate the interactive root mount prompt on mount failure.
This restores the previous behaviour. While here, match '?' and '.'
inputs exactly and improve the error message.

Requested by: avg@
Derived from a patch by: Arnaud Lacombe <lacombar@gmail.com>
2011-10-23 20:03:33 +00:00
Dag-Erling Smørgrav
e141be6f79 Revisit the capability failure trace points. The initial implementation
only logged instances where an operation on a file descriptor required
capabilities which the file descriptor did not have.  By adding a type enum
to struct ktr_cap_fail, we can catch other types of capability failures as
well, such as disallowed system calls or attempts to wrap a file descriptor
with more capabilities than it had to begin with.
2011-10-18 07:28:58 +00:00
Marcel Moolenaar
80f1c58b0a Fix double vision syndrome (read: double output) when in the
debugger without a panic.
2011-10-16 14:16:46 +00:00
Konstantin Belousov
126b36a21e Control the execution permission of the readable segments for
i386 binaries on the amd64 and ia64 with the sysctl, instead of
unconditionally enabling it.

Reviewed by:	marcel
2011-10-15 12:35:18 +00:00
Marcel Moolenaar
676eda08d0 In elf32_trans_prot() and when compiling for amd64 or ia64, add
PROT_EXECUTE when PROT_READ is needed. By default i386 allows
execution when reading is allowed and JDK 1.4.x depends on that.
2011-10-13 16:16:46 +00:00
Gleb Smirnoff
8d689e042f Make memguard(9) capable to guard uma(9) allocations. 2011-10-12 18:08:28 +00:00
Robert Watson
b160c14194 Correct a bug in export of capability-related information from the sysctls
supporting procstat -f: properly provide capability rights information to
userspace.  The bug resulted from a merge-o during upstreaming (or rather,
a failure to properly merge FreeBSD-side changed downstream).

Spotted by:     des, kibab
MFC after:      3 days
2011-10-12 12:08:03 +00:00
Adrian Chadd
df46ae53f6 Don't call fixup_filename() on each witness lock call.
This has been irking me for a while. This causes significant
CPU use on bottlenecked CPUs (eg my older EEEPC w/ an earlier
Celeron CPU and my MIPS24k boards) when they're passing
a lot of traffic.

Since the file/line values are only used for printing, this
should only affect display. It should have no operational
change on the code, besides reducing CPU use.
2011-10-12 09:21:02 +00:00
Dag-Erling Smørgrav
c601ad8eeb Add a new trace point, KTRFAC_CAPFAIL, which traces capability check
failures.  It is included in the default set for ktrace(1) and kdump(1).
2011-10-11 20:37:10 +00:00
Kirk McKusick
cd795a6e1f When unmounting a filesystem always wait for the vfs_busy lock to clear
so that if no vnodes in the filesystem are actively in use the unmount
will succeed rather than failing with EBUSY.

Reported by: Garrett Cooper
Reviewed by: Attilio Rao and Kostik Belousov
Tested by:   Garrett Cooper
PR:          kern/161016
MFC after:   3 weeks
2011-10-11 18:46:41 +00:00
Marius Strobl
f305d1b0db In device_get_children() avoid malloc(0) in order to increase portability
to other operating systems.

PR:     154287
2011-10-09 21:21:37 +00:00
Alan Cox
1549ed03ff Fix the handling of an empty kmem map by sysctl_kmem_map_free(). In
the unlikely event that sysctl_kmem_map_free() was performed on an
empty kmem map, it would incorrectly report the free space as zero.

Discussed with:	avg
MFC after:	1 week
2011-10-08 18:29:30 +00:00
Jonathan Anderson
25e33e625f Change one printf() to log().
As noted in kern/159780, printf() is not very jail-friendly, since it can't be easily monitored by jail management tools. This patch reports an error via log() instead, which, if nobody is watching the log file, still prints to the console.

Approved by: mentor (rwatson)
Submitted by: Eugene Grosbein <eugen@eg.sd.rdtc.ru>
MFC after: 5 days
2011-10-07 09:51:12 +00:00
David E. O'Brien
ef522f9515 Disallow various debug.kdb sysctl's when securelevel is raised.
PR:	161350
2011-10-07 05:47:30 +00:00
Xin LI
2b03effa01 Return proper errno when we hit error when doing sanity check.
This fixes dtrace crashes when module is not compiled with CTF
data.

Submitted by:	Paul Ambrose ambrosehua at gmail.com
MFC after:	1 week
2011-10-07 01:37:58 +00:00
Marius Strobl
880bf8b9bd - Currently, sched_balance_pair() may cause a CPU to send an IPI_PREEMPT to
itself, which sparc64 hardware doesn't support. One way to solve this
  would be to directly call sched_preempt() instead of issuing a self-IPI.
  However, quoting jhb@:
  "On the other hand, you can probably just skip the IPI entirely if we are
  going to send it to the current CPU.  Presumably, once this routine
  finishes, the current CPU will exit softlock (or will do so "soon") and
  will then pick the next thread to run based on the adjustments made in
  this routine, so there's no need to IPI the CPU running this routine
  anyway.  I think this is the better solution.  Right now what is probably
  happening on other platforms is as soon as this routine finishes the CPU
  processes its self-IPI and causes mi_switch() which will just switch back
  to the softclock thread it is already running."
- With r226054 and the the above change in place, sparc64 now no longer is
  incompatible with ULE and vice versa. However, powerpc/E500 still is.

Submitted by:	jhb
Reviewed by:	jeff
2011-10-06 11:48:13 +00:00
Edward Tomasz Napierala
4ce9c95bd8 Remove assertion against empty NFSv4 ACLs. An empty ACL is not exactly
valid - we don't allow for setting it on a file, for example - but it's
not something we should assert on.

For STABLE kernel, it changes nothing, because it's not compiled with
INVARIANTS.  If it was, it would fix crashes.  It also fixes an assert
in libc encountered with NFSv4 without nfsuserd(8) running.

Submitted by:	Yuri Pankov (earlier version)
MFC after:	1 month
2011-10-05 17:29:49 +00:00
Konstantin Belousov
a101072d7f Supply unique (st_dev, st_ino) value pair for the fstat(2) done on the pipes.
Reviewed by:	jhb, Peter Jeremy <peterjeremy acm org>
MFC after:	2 weeks
2011-10-05 16:56:06 +00:00
Konstantin Belousov
837b4d462d Move parts of the commit log for r166167, where Tor explained the
interaction between vnode locks and vfs_busy(), into comment.

MFC after:	1 week
2011-10-04 18:45:29 +00:00
Edward Tomasz Napierala
c0c0936205 Actually enforce limit for inheritable resources on fork.
MFC after:	3 days
2011-10-04 14:56:33 +00:00
Edward Tomasz Napierala
2d8696d1e8 Move some code inside the racct_proc_fork(); it spares a few lock operations
and it's more logical this way.

MFC after:	3 days
2011-10-03 17:40:55 +00:00
Konstantin Belousov
24f3dcfe50 Assert that exiting process does not return to usermode.
Reviewed by:	avg, jhb
MFC after:	1 week
2011-10-03 16:58:58 +00:00
Edward Tomasz Napierala
72a401d918 Fix another bug introduced in r225641, which caused rctl to access certain
fields in 'struct proc' before they got initialized in do_fork().

MFC after:	3 days
2011-10-03 16:23:20 +00:00
Edward Tomasz Napierala
ac6fafe6c2 Fix bug introduced in r225641, which would cause panic if racct_proc_fork()
returned error -- the racct_destroy_locked() would get called twice.

MFC after:	3 days
2011-10-03 15:32:15 +00:00
Konstantin Belousov
8e9a54ee46 The sigwait(3) function shall not return EINTR, according to the
POSIX/SUSvN. The sigwait(2) syscall does return EINTR, and libc.so.7
contains the wrapper sigwait(3) which hides EINTR from callers.  The
EINTR return is used by libthr to handle required cancellation point
in the sigwait(3).

To help the binaries linked against pre-libc.so.7, i.e. RELENG_6 and
earlier, to have right ABI for sigwait(3), transform EINTR return from
sigwait(2) into ERESTART.

Discussed with:	davidxu
MFC after:	1 week
2011-10-01 10:18:55 +00:00
Bjoern A. Zeeb
a06534c3c2 Fix handling of corrupt compress(1)ed data. [11:04]
Add missing length checks on unix socket addresses. [11:05]

Approved by:	so (cperciva)
Approved by:	re (kensmith)
Security:	FreeBSD-SA-11:04.compress
Security:	CVE-2011-2895 [11:04]
Security:	FreeBSD-SA-11:05.unix
2011-09-28 08:47:17 +00:00
Attilio Rao
79a5956c23 Revert r225372:
wdog_kern_pat() acquires eventhandler mutex, thus it cannot work in
kernel context (from where kdb_trap() runs).

The right way to fix this is both offering the
cpu-stop-on-panic-and-skip-locking logic and also a context for KDB
to officially run. We can re-enable this (or a similar) improvement
when these 2 patches hit the tree.

Sponsored by:	Sandvine Incorporated
Discussed with:	emaste, rstone
MFC after:	immediately
2011-09-27 13:42:11 +00:00
Konstantin Belousov
ce8bd78b2a Do not deliver SIGTRAP on exec as the normal signal, use ptracestop() on
syscall exit path. Otherwise, if SIGTRAP is ignored, that tdsendsignal()
do not want to deliver the signal, and debugger never get a notification
of exec.

Found and tested by:	Anton Yuzhaninov <citrin citrin ru>
Discussed with:	jhb
MFC after:	2 weeks
2011-09-27 13:17:02 +00:00
Alexander Motin
556a5850fa Fix interrupt counters dumping on SW_WATCHDOG fire. 2011-09-27 09:30:20 +00:00
Edward Tomasz Napierala
1dbf9dcc20 Fix error handling bug that would prevent MAC structures from getting
freed properly if resource limit got exceeded.

Approved by:	re (kib)
2011-09-17 20:48:49 +00:00
Edward Tomasz Napierala
b38520f09c Fix long-standing thinko regarding maxproc accounting. Basically,
we were accounting the newly created process to its parent instead
of the child itself.  This caused problems later, when the child
changed its credentials - the per-uid, per-jail etc counters were
not properly updated, because the maxproc counter in the child
process was 0.

Approved by:	re (kib)
2011-09-17 19:55:32 +00:00
Kip Macy
9eca9361f9 Auto-generated code from sys_ prefixing makesyscalls.sh change
Approved by:	re(bz)
2011-09-16 14:04:14 +00:00
Kip Macy
8451d0dd78 In order to maximize the re-usability of kernel code in user space this
patch modifies makesyscalls.sh to prefix all of the non-compatibility
calls (e.g. not linux_, freebsd32_) with sys_ and updates the kernel
entry points and all places in the code that use them. It also
fixes an additional name space collision between the kernel function
psignal and the libc function of the same name by renaming the kernel
psignal kern_psignal(). By introducing this change now we will ease future
MFCs that change syscalls.

Reviewed by:	rwatson
Approved by:	re (bz)
2011-09-16 13:58:51 +00:00
Adrian Chadd
d2849f27bc Ensure that ta_pending doesn't overflow u_short by capping its value at USHRT_MAX.
If it overflows before the taskqueue can run, the task will be
re-added to the taskqueue and cause a loop in the task list.

Reported by:	Arnaud Lacombe <lacombar@gmail.com>
Submitted by:	Ryan Stone <rysto32@gmail.com>
Reviewed by:	jhb
Approved by:	re (kib)
MFC after:	1 day
2011-09-15 08:42:06 +00:00
Rick Macklem
4d30adc494 Modify vfs_register() to use a hash calculation
on vfc_name to set vfc_typenum, so that vfc_typenum doesn't
change when file systems are loaded in different orders. This
keeps NFS file handles from changing, for file systems that
use vfc_typenum in their fsid. This change is controlled via
a loader.conf variable called vfs.typenumhash, since vfc_typenum
will change once when this is enabled. It defaults to 1 for
9.0, but will default to 0 when MFC'd to stable/8.

Tested by:	hrs
Reviewed by:	jhb, pjd (earlier version)
Approved by:	re (kib)
MFC after:	1 month
2011-09-13 21:01:26 +00:00
Attilio Rao
58379067a3 dump_write() returns ENXIO if the dump is trying to be written outside
of the device boundry.
While this is generally ok, the problem is that all the consumers
handle similar cases (and expect to catch) ENOSPC for this (for a
reference look at minidumpsys() and dumpsys() constructions). That
ends up in consumers not recognizing the issue and amd64 failing to
retry if the number of pages grows up during minidump.
Fix this by returning ENOSPC in dump_write() and while here add some
more diagnostic on involved values.

Sponsored by:	Sandvine Incorporated
In collabouration with:	emaste
Approved by:	re (kib)
MFC after:	10 days
2011-09-12 20:39:31 +00:00
Ed Schouten
ca0856d3d1 Fix error return codes for ioctls on init/lock state devices.
In revision 223722 we introduced support for driver ioctls on init/lock
state devices. Unfortunately the call to ttydevsw_cioctl() clobbers the
value of the error variable, meaning that in many cases ioctl() will now
return ENOTTY, even though the ioctl() was processed properly.

Reported by:	Boris Samorodov <bsam ipt ru>
Patch by:	jilles@
Approved by:	re@ (kib@)
2011-09-12 10:07:21 +00:00
Konstantin Belousov
26ccf4f10f Inline the syscallenter() and syscallret(). This reduces the time measured
by the syscall entry speed microbenchmarks by ~10% on amd64.

Submitted by:	jhb
Approved by:	re (bz)
MFC after:	2 weeks
2011-09-11 16:05:09 +00:00
Attilio Rao
fa2b39a18d Improve the informations reported in case of busy buffers during the shutdown:
- Axe out the SHOW_BUSYBUFS option and uses a tunable for selectively
enable/disable it, which is defaulted for not printing anything (0
value) but can be changed for printing (1 value) and be verbose (2
value)
- Improves the informations outputed: right now, there is no track of
the actual struct buf object or vnode which are referenced by the
shutdown process, but it is printed the related struct bufobj object
which is not really helpful
- Add more verbosity about the state of the struct buf lock and the
vnode informations, with the latter to be activated separately by the
sysctl

Sponsored by:	Sandvine Incorporated
Reviewed by:	emaste, kib
Approved by:	re (ksmith)
MFC after:	10 days
2011-09-08 12:56:26 +00:00
Edward Tomasz Napierala
ba1b206990 Fix whitespace.
Submitted by:	amdmi3
Approved by:	re (rwatson)
2011-09-07 07:52:45 +00:00
Edward Tomasz Napierala
3044751e35 Work around a kernel panic triggered by forkbomb with an rctl rule
such as j:name:maxproc:sigkill=100.  Proper fix - deferring psignal
to a taskqueue - is somewhat complicated and thus will happen
after 9.0.

Approved by:	re (kib)
2011-09-06 17:22:40 +00:00
Attilio Rao
9f39e22e6d Interrupts are disabled/enabled when entering and exiting the KDB context.
While this is generally good, it brings along a serie of problems,
like clocks going off sync and in presence of SW_WATCHDOG, watchdogs
firing without a good reason (missed hardclock wdog ticks update).

Fix the latter by kicking the watchdog just before to re-enable the interrupts.
Also, while here, not rely on users to stop the watchdog manually when
entering DDB but do that when entering KDB context.

Sponsored by: Sandvine Incorporated
Reviewed by:	emaste, rstone
Approved by:	re (kib)
MFC after:	1 week
2011-09-04 13:07:02 +00:00
Edward Tomasz Napierala
cff08ec0f4 Since r224036 the cputime and wallclock are supposed to be in seconds,
not microseconds.  Make it so.

Approved by:	re (kib)
2011-09-04 05:04:34 +00:00
Edward Tomasz Napierala
2419d7f93b Fix panic that happens when fork(2) fails due to a limit other than
the rctl one - for example, it happens when someone reaches maximum
number of processes in the system.

Approved by:	re (kib)
2011-09-03 08:08:24 +00:00
Robert Watson
9b6dd12e5d Correct several issues in the integration of POSIX shared memory objects
and the new setmode and setowner fileops in FreeBSD 9.0:

- Add new MAC Framework entry point mac_posixshm_check_create() to allow
  MAC policies to authorise shared memory use.  Provide a stub policy and
  test policy templates.

- Add missing Biba and MLS implementations of mac_posixshm_check_setmode()
  and mac_posixshm_check_setowner().

- Add 'accmode' argument to mac_posixshm_check_open() -- unlike the
  mac_posixsem_check_open() entry point it was modeled on, the access mode
  is required as shared memory access can be read-only as well as writable;
  this isn't true of POSIX semaphores.

- Implement full range of POSIX shared memory entry points for Biba and MLS.

Sponsored by:   Google Inc.
Obtained from:	TrustedBSD Project
Approved by:    re (kib)
2011-09-02 17:40:39 +00:00
Robert Watson
4cf7545589 Attempt to make break-to-debugger and alternative break-to-debugger more
accessible:

(1) Always compile in support for breaking into the debugger if options
    KDB is present in the kernel.

(2) Disable both by default, but allow them to be enabled via tunables
    and sysctls debug.kdb.break_to_debugger and
    debug.kdb.alt_break_to_debugger.

(3) options BREAK_TO_DEBUGGER and options ALT_BREAK_TO_DEBUGGER continue
    to behave as before -- only now instead of compiling in
    break-to-debugger support, they change the default values of the
    above sysctls to enable those features by default.  Current kernel
    configurations should, therefore, continue to behave as expected.

(4) Migrate alternative break-to-debugger state machine logic out of
    individual device drivers into centralised KDB code.  This has a
    number of upsides, but also one downside: it's now tricky to release
    sio spin locks when entering the debugger, so we don't.  However,
    similar logic does not exist in other device drivers, including uart.

(5) dcons requires some special handling; unlike other console types, it
    allows overriding KDB's own debugger selection, so we need a new
    interface to KDB to allow that to work.

GENERIC kernels in -CURRENT will now support break-to-debugger as long as
appropriate boot/run-time options are set, which should improve the
debuggability of BETA kernels significantly.

MFC after:	3 weeks
Reviewed by:	kib, nwhitehorn
Approved by:	re (bz)
2011-08-26 21:46:36 +00:00
Xin LI
cd39bb098e Fix format strings for KTR_STATE in 4BSD ad ULE schedulers.
Submitted by:	Ivan Klymenko <fidaj@ukr.net>
PR:		kern/159904, kern/159905
MFC after:	2 weeks
Approved by:	re (kib)
2011-08-26 18:00:07 +00:00
Jamie Gritton
e6d5cb63fa Delay the recursive decrement of pr_uref when jails are made invisible
but not removed; decrement it instead when the child jail actually
goes away. This avoids letting the counter go below zero in the case
where dying (pr_uref==0) jails are "resurrected", and an associated
KASSERT panic.

Submitted by:	Steven Hartland
Approved by:	re (bz)
MFC after:	1 week
2011-08-26 16:03:34 +00:00
Attilio Rao
6aba400a70 Fix a deficiency in the selinfo interface:
If a selinfo object is recorded (via selrecord()) and then it is
quickly destroyed, with the waiters missing the opportunity to awake,
at the next iteration they will find the selinfo object destroyed,
causing a PF#.

That happens because the selinfo interface has no way to drain the
waiters before to destroy the registered selinfo object. Also this
race is quite rare to get in practice, because it would require a
selrecord(), a poll request by another thread and a quick destruction
of the selrecord()'ed selinfo object.

Fix this by adding the seldrain() routine which should be called
before to destroy the selinfo objects (in order to avoid such case),
and fix the present cases where it might have already been called.
Sometimes, the context is safe enough to prevent this type of race,
like it happens in device drivers which installs selinfo objects on
poll callbacks. There, the destruction of the selinfo object happens
at driver detach time, when all the filedescriptors should be already
closed, thus there cannot be a race.
For this case, mfi(4) device driver can be set as an example, as it
implements a full correct logic for preventing this from happening.

Sponsored by:	Sandvine Incorporated
Reported by:	rstone
Tested by:	pluknet
Reviewed by:	jhb, kib
Approved by:	re (bz)
MFC after:	3 weeks
2011-08-25 15:51:54 +00:00
Bjoern A. Zeeb
b233773bb9 Increase the defaults for the maximum socket buffer limit,
and the maximum TCP send and receive buffer limits from 256kB
to 2MB.

For sb_max_adj we need to add the cast as already used in the sysctl
handler to not overflow the type doing the maths.

Note that this is just the defaults.  They will allow more memory
to be consumed per socket/connection if needed but not change the
default "idle" memory consumption.   All values are still tunable
by sysctls.

Suggested by:	gnn
Discussed on:	arch (Mar and Aug 2011)
MFC after:	3 weeks
Approved by:	re (kib)
2011-08-25 09:20:13 +00:00
Martin Matuska
82378711f9 Generalize ffs_pages_remove() into vn_pages_remove().
Remove mapped pages for all dataset vnodes in zfs_rezget() using
new vn_pages_remove() to fix mmapped files changed by
zfs rollback or zfs receive -F.

PR:		kern/160035, kern/156933
Reviewed by:	kib, pjd
Approved by:	re (kib)
MFC after:	1 week
2011-08-25 08:17:39 +00:00
Attilio Rao
e75baa2802 callout_cpu_switch() allows preemption when dropping the outcoming
callout cpu lock (and after having dropped it).
If the newly scheduled thread wants to acquire the old queue it will
just spin forever.

Fix this by disabling preemption and interrupts entirely (because fast
interrupt handlers may incur in the same problem too) while switching
locks.

Reported by:	hrs, Mike Tancsa <mike AT sentex DOT net>,
		Chip Camden <sterling AT camdensoftware DOT com>
Tested by:	hrs, Mike Tancsa <mike AT sentex DOT net>,
		Chip Camden <sterling AT camdensoftware DOT com>,
		Nicholas Esborn <nick AT desert DOT net>
Approved by:	re (kib)
MFC after:	10 days
2011-08-21 10:52:50 +00:00
Konstantin Belousov
aab4f50170 Prevent the hiwatermark for the unix domain socket from becoming
effectively negative. Often seen as upstream fastcgi connection timeouts
in nginx when using sendfile over unix domain sockets for communication.

Sendfile(2) may send more bytes then currently allowed by the
hiwatermark of the socket, e.g. because the so_snd sockbuf lock is
dropped after sbspace() call in the kern_sendfile() loop. In this case,
recalculated hiwatermark will overflow. Since lowatermark is renewed
as half of the hiwatermark by sendfile code, and both are unsigned,
the send buffer never reaches the free space requested by lowatermark,
causing indefinite wait in sendfile.

Reviewed by:	rwatson
Approved by:	re (bz)
MFC after:	2 weeks
2011-08-20 16:12:29 +00:00
Robert Watson
311fa10b52 r222015 introduced a new assertion that the size of a fixed-length sbuf
buffer is greater than 1.  This triggered panics in at least one spot in
the kernel (the MAC Framework) which passes non-negative, rather than >1
buffer sizes based on the size of a user buffer passed into a system
call.  While 0-size buffers aren't particularly useful, they also aren't
strictly incorrect, so loosen the assertion.

Discussed with:	phk (fears I might be EDOOFUS but willing to go along)
Spotted by:	pho + stress2
Approved by:	re (kib)
2011-08-19 08:29:10 +00:00
Jonathan Anderson
f8ca0a757a Auto-generated system call code based on r224987.
Approved by:	re (implicit)
2011-08-18 23:08:52 +00:00
Jonathan Anderson
cfb5f76865 Add experimental support for process descriptors
A "process descriptor" file descriptor is used to manage processes
without using the PID namespace. This is required for Capsicum's
Capability Mode, where the PID namespace is unavailable.

New system calls pdfork(2) and pdkill(2) offer the functional equivalents
of fork(2) and kill(2). pdgetpid(2) allows querying the PID of the remote
process for debugging purposes. The currently-unimplemented pdwait(2) will,
in the future, allow querying rusage/exit status. In the interim, poll(2)
may be used to check (and wait for) process termination.

When a process is referenced by a process descriptor, it does not issue
SIGCHLD to the parent, making it suitable for use in libraries---a common
scenario when using library compartmentalisation from within large
applications (such as web browsers). Some observers may note a similarity
to Mach task ports; process descriptors provide a subset of this behaviour,
but in a UNIX style.

This feature is enabled by "options PROCDESC", but as with several other
Capsicum kernel features, is not enabled by default in GENERIC 9.0.

Reviewed by: jhb, kib
Approved by: re (kib), mentor (rwatson)
Sponsored by: Google Inc
2011-08-18 22:51:30 +00:00
John Baldwin
f55d3fbe84 One of the general principles of the sysctl(3) API is that a user can
query the needed size for a sysctl result by passing in a NULL old
pointer and a valid oldsize.  The kern.proc.args sysctl handler broke
this assumption by not calling SYSCTL_OUT() if the old pointer was
NULL.

Approved by:	re (kib)
MFC after:	3 days
2011-08-18 22:20:45 +00:00
Konstantin Belousov
68889ed699 Fix build breakage. Initialize error variables explicitely for !MAC case.
Pointy hat to:	kib
Approved by:	re (bz)
2011-08-17 12:37:14 +00:00
Konstantin Belousov
9c00bb9190 Add the fo_chown and fo_chmod methods to struct fileops and use them
to implement fchown(2) and fchmod(2) support for several file types
that previously lacked it. Add MAC entries for chown/chmod done on
posix shared memory and (old) in-kernel posix semaphores.

Based on the submission by:	glebius
Reviewed by:	rwatson
Approved by:	re (bz)
2011-08-16 20:07:47 +00:00
Jonathan Anderson
d6f7248983 poll(2) implementation for capabilities.
When calling poll(2) on a capability, unwrap first and then poll the
underlying object.

Approved by: re (kib), mentor (rwatson)
Sponsored by: Google Inc
2011-08-16 14:14:56 +00:00
Robert Watson
359b396113 Trim some warnings and notes from capabilities.conf -- these are left over
from Capsicum development, and no longer apply.

Approved by:	re (kib)
Sponsored by:	Google Inc
2011-08-13 17:22:16 +00:00
Robert Watson
fd9a5f73f6 When falloc() was broken into separate falloc_noinstall() and finstall(),
a bug was introduced in kern_openat() such that the error from the vnode
open operation was overwritten before it was passed as an argument to
dupfdopen().  This broke operations on /dev/{stdin,stdout,stderr}.  Fix
by preserving the original error number across finstall() so that it is
still available.

Approved by:	re (kib)
Reported by:	cognet
2011-08-13 16:03:40 +00:00
Robert Watson
854d7b9fc8 Update use of the FEATURE() macro in sys_capability.c to reflect the move
to two different kernel options for capability mode vs. capabilities.

Approved by:	re (bz)
2011-08-13 13:34:01 +00:00
Robert Watson
73516dbd27 Now that capability support has been committed, update and expand the
comment at the type of sys_capability.c to describe its new contents.

Approved by:  re (xxx)
2011-08-13 13:26:40 +00:00
Robert Watson
74536eddbe Regenerate system call files following r224812 changes to capabilities.conf.
A no-op for non-Capsicum kernels; for Capsicum kernels, completes the
enabling of fooat(2) system calls using capabilities.  With this change,
and subject to bug fixes, Capsicum capability support is now complete for
9.0.

Approved by:    re (kib)
Submitted by:   jonathan
Sponsored by:   Google Inc
2011-08-13 12:14:40 +00:00
Jonathan Anderson
bc69c09054 Allow openat(2), fstatat(2), etc. in capability mode.
namei() and lookup() can now perform "strictly relative" lookups.
Such lookups, performed when in capability mode or when looking up
relative to a directory capability, enforce two policies:
 - absolute paths are disallowed (including symlinks to absolute paths)
 - paths containing '..' components are disallowed

These constraints make it safe to enable openat() and friends.
These system calls are instrumental in supporting Capsicum
components such as the capability-mode-aware runtime linker.

Finally, adjust comments in capabilities.conf to reflect the actual state
of the world (e.g. shm_open(2) already has the appropriate constraints,
getdents(2) already requires CAP_SEEK).

Approved by: re (bz), mentor (rwatson)
Sponsored by: Google Inc.
2011-08-13 10:43:21 +00:00
Jonathan Anderson
69d377fe1b Allow Capsicum capabilities to delegate constrained
access to file system subtrees to sandboxed processes.

- Use of absolute paths and '..' are limited in capability mode.
- Use of absolute paths and '..' are limited when looking up relative
  to a capability.
- When a name lookup is performed, identify what operation is to be
  performed (such as CAP_MKDIR) as well as check for CAP_LOOKUP.

With these constraints, openat() and friends are now safe in capability
mode, and can then be used by code such as the capability-mode runtime
linker.

Approved by: re (bz), mentor (rwatson)
Sponsored by: Google Inc
2011-08-13 09:21:16 +00:00
Jonathan Anderson
d1b6899e83 Rename CAP_*_KEVENT to CAP_*_EVENT.
Change the names of a couple of capability rights to be less
FreeBSD-specific.

Approved by: re (kib), mentor (rwatson)
Sponsored by: Google Inc
2011-08-12 14:26:47 +00:00
Jonathan Anderson
d6d2cfa24b Only call fdclose() on successfully-opened FDs.
Since kern_openat() now uses falloc_noinstall() and finstall() separately,
there are cases where we could get to cleanup code without ever creating
a file descriptor. In those cases, we should not call fdclose() on FD -1.

Approved by: re (kib), mentor (rwatson)
Sponsored by: Google Inc
2011-08-11 13:29:59 +00:00
Robert Watson
a9d2f8d84f Second-to-last commit implementing Capsicum capabilities in the FreeBSD
kernel for FreeBSD 9.0:

Add a new capability mask argument to fget(9) and friends, allowing system
call code to declare what capabilities are required when an integer file
descriptor is converted into an in-kernel struct file *.  With options
CAPABILITIES compiled into the kernel, this enforces capability
protection; without, this change is effectively a no-op.

Some cases require special handling, such as mmap(2), which must preserve
information about the maximum rights at the time of mapping in the memory
map so that they can later be enforced in mprotect(2) -- this is done by
narrowing the rights in the existing max_protection field used for similar
purposes with file permissions.

In namei(9), we assert that the code is not reached from within capability
mode, as we're not yet ready to enforce namespace capabilities there.
This will follow in a later commit.

Update two capability names: CAP_EVENT and CAP_KEVENT become
CAP_POST_KEVENT and CAP_POLL_KEVENT to more accurately indicate what they
represent.

Approved by:	re (bz)
Submitted by:	jonathan
Sponsored by:	Google Inc
2011-08-11 12:30:23 +00:00
Martin Matuska
d16eac5c57 Revert r224655 and r224614 because vn_fullpath* does not always work
on nullfs mounts.

Change shall be reconsidered after 9.0 is released.

Requested by:	re (kib)
Approved by:	re (kib)
2011-08-08 14:02:08 +00:00
Martin Matuska
5388625fff The change in r224615 didn't take into account that vn_fullpath_global()
doesn't operate on locked vnode. This could cause a panic.

Fix by unlocking vnode, re-locking afterwards and verifying that it wasn't
renamed or deleted. To improve readability and reduce code size, move code
to a new static function vfs_verify_global_path().

In addition, fix missing giant unlock in unmount().

Reported by:	David Wolfskill <david@catwhisker.org>
Reviewed by:	kib
Approved by:	re (bz)
MFC after:	2 weeks
2011-08-05 11:12:50 +00:00
Martin Matuska
435d46675d Always disable mount and unmount for jails with enforce_statfs==2.
A working statfs(2) is required for umount(8) in jail.

Reviewed by:	pjd, kib
Approved by:	re (kib)
MFC after:	2 weeks
2011-08-02 19:44:40 +00:00
Martin Matuska
f6c1d63e47 For mount, discover f_mntonname from supplied path argument
using vn_fullpath_global(). This fixes f_mntonname if mounting
inside chroot, jail or with relative path as argument.

For unmount in jail, use vn_fullpath_global() to discover
global path from supplied path argument. This fixes unmount in jail.

Reviewed by:	pjd, kib
Approved by:	re (kib)
MFC after:	2 weeks
2011-08-02 19:13:56 +00:00
Konstantin Belousov
d0a724c5ea Fix the LK_NOSHARE lockmgr flag interaction with LK_UPGRADE and
LK_DOWNGRADE lock ops. Namely, the ops should be NOP since LK_NOSHARE
locks are always exclusive.

Reported by:	rmacklem
Reviewed by:	attilio
Tested by:	pho
Approved by:	re (kensmith)
MFC after:	1 week
2011-08-01 19:07:03 +00:00
Gleb Smirnoff
062393fe00 Don't leak kld_sx lock in kldunloadf().
Approved by:	re (kib)
2011-07-31 13:49:15 +00:00
Andriy Gapon
35edc49853 smp_rendezvous: master cpu should wait until all slaves are fully done
This is a followup to r222032 and a reimplementation of it.
While that revision fixed the race for the smp_rv_waiters[2] exit
sentinel, it still left a possibility for a target CPU to access
stale or wrong smp_rv_func_arg in smp_rv_teardown_func.
To fix this race the slave CPUs signal when they are really fully
done with the rendezvous and the master CPU waits until all slaves
are done.

Diagnosed by:	kib
Reviewed by:	jhb, mlaier, neel
Approved by:	re (kib)
MFC after:	2 weeks
2011-07-30 20:29:39 +00:00
Konstantin Belousov
889dffba25 Fix the devmtx lock leak from make_dev(9) when the old device cloning
failed due to invalid or duplicated path being generated.

Reviewed by:	jh
Approved by:	re (kensmith)
MFC after:	1 week
2011-07-30 14:12:37 +00:00
Andriy Gapon
7a0b13ed28 remove RESTARTABLE_PANICS option
This is done per request/suggestion from John Baldwin
who introduced the option.  Trying to resume normal
system operation after a panic is very unpredictable
and dangerous.  It will become even more dangerous
when we allow a thread in panic(9) to penetrate all
lock contexts.
I understand that the only purpose of this option was
for testing scenarios potentially resulting in panic.

Suggested by:	jhb
Reviewed by:	attilio, jhb
X-MFC-After:	never
Approved by:	re (kib)
2011-07-25 09:12:48 +00:00
Kirk McKusick
d716efa9f7 Move the MNTK_SUJ flag in mnt_kern_flag to MNT_SUJ in mnt_flag
so that it is visible to userland programs. This change enables
the `mount' command with no arguments to be able to show if a
filesystem is mounted using journaled soft updates as opposed
to just normal soft updates.

Approved by: re (bz)
2011-07-24 18:27:09 +00:00
Kirk McKusick
6beb3bb4eb This update changes the mnt_flag field in the mount structure from
32 bits to 64 bits and eliminates the unused mnt_xflag field.  The
existing mnt_flag field is completely out of bits, so this update
gives us room to expand. Note that the f_flags field in the statfs
structure is already 64 bits, so the expanded mnt_flag field can
be exported without having to make any changes in the statfs structure.

Approved by: re (bz)
2011-07-24 17:43:09 +00:00
Jonathan Anderson
7a270867e7 Turn on AUDIT_ARG_RIGHTS() for cap_new(2).
Now that the code is in place to audit capability method rights, start
using it to audit the 'rights' argument to cap_new(2).

Approved by: re (kib), mentor (rwatson)
Sponsored by: Google Inc
2011-07-22 12:50:21 +00:00
Jonathan Anderson
c30b9b5169 Export capability information via sysctls.
When reporting on a capability, flag the fact that it is a capability,
but also unwrap to report all of the usual information about the
underlying file.

Approved by: re (kib), mentor (rwatson)
Sponsored by: Google Inc
2011-07-20 09:53:35 +00:00
Attilio Rao
6338c57958 Remove explicit MAXCPU usage from sys/pcpu.h avoiding a namespace
pollution.  That is a step further in the direction of building correct
policies for userland and modules on how to deal with the number of
maxcpus at runtime.

Reported by:	jhb
Reviewed and tested by:	pluknet
Approved by:	re (kib)
2011-07-19 16:50:55 +00:00
Attilio Rao
edf26ab83e Remove pc_name member of struct pcpu.
pc_name is only included when KTR option is and it does introduce a
subdle KBI breakage that totally breaks vmstat when world and kernel are
not in sync.
Besides, it is not used somewhere.

In collabouration with:	pluknet
Reviewed by:	jhb
Approved by:	re (kib)
2011-07-19 14:57:59 +00:00
Bjoern A. Zeeb
925af54487 Rename ki_ocomm to ki_tdname and OCOMMLEN to TDNAMLEN.
Provide backward compatibility defines under BURN_BRIDGES.

Suggested by:	jhb
Reviewed by:	emaste
Sponsored by:	Sandvine Incorporated
Approved by:	re (kib)
2011-07-18 20:06:15 +00:00
John Baldwin
2417d97ebb - Export each thread's individual resource usage in in struct kinfo_proc's
ki_rusage member when KERN_PROC_INC_THREAD is passed to one of the
  process sysctls.
- Correctly account for the current thread's cputime in the thread when
  doing the runtime fixup in calcru().
- Use TIDs as the key to lookup the previous thread to compute IO stat
  deltas in IO mode in top when thread display is enabled.

Reviewed by:	kib
Approved by:	re (kib)
2011-07-18 17:33:08 +00:00
Attilio Rao
521ea19d1c - Remove the eintrcnt/eintrnames usage and introduce the concept of
sintrcnt/sintrnames which are symbols containing the size of the 2
  tables.
- For amd64/i386 remove the storage of intr* stuff from assembly files.
  This area can be widely improved by applying the same to other
  architectures and likely finding an unified approach among them and
  move the whole code to be MI. More work in this area is expected to
  happen fairly soon.

No MFC is previewed for this patch.

Tested by:	pluknet
Reviewed by:	jhb
Approved by:	re (kib)
2011-07-18 15:19:40 +00:00
Robert Watson
ff66f6a404 Define two new sysctl node flags: CTLFLAG_CAPRD and CTLFLAG_CAPRW, which
may be jointly referenced via the mask CTLFLAG_CAPRW.  Sysctls with these
flags are available in Capsicum's capability mode; other sysctl nodes are
not.

Flag several useful sysctls as available in capability mode, such as memory
layout sysctls required by the run-time linker and malloc(3).  Also expose
access to randomness and available kernel features.

A few sysctls are enabled to support name->MIB conversion; these may leak
information to capability mode by virtue of providing resolution on names
not flagged for access in capability mode.  This is, generally, not a huge
problem, but might be something to resolve in the future.  Flag these cases
with XXX comments.

Submitted by:	jonathan
Sponsored by:	Google, Inc.
2011-07-17 23:05:24 +00:00
Ryan Stone
05a4755ef6 Fix a LOR between hwpmc and the kernel linker. When a system-wide
sampling mode PMC is allocated, hwpmc calls linker_hwpmc_list_objects()
while already holding an exclusive lock on pmc-sx lock.  list_objects()
tries to acquire an exclusive lock on the kld_sx lock.  When a KLD module
is loaded or unloaded successfully, kern_kld(un)load calls into the pmc
hook while already holding an exclusive lock on the kld_sx lock.  Calling
the pmc hook requires acquiring a shared lock on the pmc-sx lock.

Fix this by only acquiring a shared lock on the kld_sx lock in
linker_hwpmc_list_objects(), and also downgrading to a shared lock on the
kld_sx lock in kern_kld(un)load before calling into the pmc hook.  In
kern_kldload this required moving some modifications of the linker_file_t
to happen before calling into the pmc hook.

This fixes the deadlock by ensuring that the hwpmc -> list_objects() case
is always able to proceed.  Without this patch, I was able to deadlock a
multicore system within minutes by constantly loading and unloading an KLD
module while I simultaneously started a sampling mode PMC in a loop.

MFC after:	1 month
2011-07-17 21:53:42 +00:00
Jonathan Anderson
63ba8b5ede Auto-generated system call code with cap_new(), cap_getrights().
Approved by: mentor (rwatson), re (Capsicum blanket)
Sponsored by: Google Inc
2011-07-15 18:33:12 +00:00
Jonathan Anderson
cfb9df5541 Add cap_new() and cap_getrights() system calls.
Implement two previously-reserved Capsicum system calls:
- cap_new() creates a capability to wrap an existing file descriptor
- cap_getrights() queries the rights mask of a capability.

Approved by: mentor (rwatson), re (Capsicum blanket)
Sponsored by: Google Inc
2011-07-15 18:26:19 +00:00
Jonathan Anderson
745bae379d Add implementation for capabilities.
Code to actually implement Capsicum capabilities, including fileops and
kern_capwrap(), which creates a capability to wrap an existing file
descriptor.

We also modify kern_close() and closef() to handle capabilities.

Finally, remove cap_filelist from struct capability, since we don't
actually need it.

Approved by: mentor (rwatson), re (Capsicum blanket)
Sponsored by: Google Inc
2011-07-15 09:37:14 +00:00