Commit Graph

239 Commits

Author SHA1 Message Date
Mateusz Guzik
84267cacf4 sysctl: don't modify oid_running for static nodes
It is necessary to prevent nodes from being destroyed while used, but static
ones cannot be destroyed.
2014-12-28 19:24:01 +00:00
Mateusz Guzik
f84f8f9468 Now that sysctl_root is only called with sysctl lock in shared mode, update
its assertion to require that.

Update comment missed in r273400: sysctl_xlock/unlock -> sysctl_xlock/xunlock

Noted by: jhb
2014-10-26 01:47:55 +00:00
Dag-Erling Smørgrav
b0d69dfad9 In all cases except CTLTYPE_STRING, penv is NULL here, so passing it
indiscriminately to printf() and freeenv() is incorrect.  Add a NULL
check before freeenv(); as for printf(), we could use req.newptr
instead, but we'd have to select the correct format string based on
the type, and that's too much work for an error message, so just
remove it.
2014-10-23 22:42:56 +00:00
Mateusz Guzik
fca7732078 Mark some more sysctl stuff shared-locked and MPSAFE. 2014-10-21 21:08:45 +00:00
Mateusz Guzik
b564c5d6aa Make sysctl name2oid shared-locked as well.
This is a follow-up to r273401.
2014-10-21 19:45:08 +00:00
Mateusz Guzik
efe0abddf5 Implement shared locking for sysctl. 2014-10-21 19:05:44 +00:00
Mateusz Guzik
580a011762 Rename sysctl_lock and _unlock to sysctl_xlock and _xunlock. 2014-10-21 19:02:26 +00:00
Davide Italiano
2be111bf7d Follow up to r225617. In order to maximize the re-usability of kernel code
in userland rename in-kernel getenv()/setenv() to kern_setenv()/kern_getenv().
This fixes a namespace collision with libc symbols.

Submitted by:   kmacy
Tested by:      make universe
2014-10-16 18:04:43 +00:00
Mateusz Guzik
30d58d6b39 Don't make a temporary copy of fixed sysctl strings. 2014-07-10 21:46:57 +00:00
Hans Petter Selasky
604bf9d37e When getting the initial value of numeric tunables use the
getenv_xxx() functions instead of strtoq(), because the getenv_xxx()
functions include wrappers for various postfixes like G/M/K, which
strtoq() doesn't do.
2014-07-05 06:12:48 +00:00
Hans Petter Selasky
6a3287f889 Fix regression issue after r267961. Handle special string case for
SYSCTLs like previously.

MFC after:	2 weeks
Reported by:	several people
2014-06-28 03:59:04 +00:00
Hans Petter Selasky
af3b2549c4 Pull in r267961 and r267973 again. Fix for issues reported will follow. 2014-06-28 03:56:17 +00:00
Glen Barber
37a107a407 Revert r267961, r267973:
These changes prevent sysctl(8) from returning proper output,
such as:

 1) no output from sysctl(8)
 2) erroneously returning ENOMEM with tools like truss(1)
    or uname(1)
 truss: can not get etype: Cannot allocate memory
2014-06-27 22:05:21 +00:00
Hans Petter Selasky
3da1cf1e88 Extend the meaning of the CTLFLAG_TUN flag to automatically check if
there is an environment variable which shall initialize the SYSCTL
during early boot. This works for all SYSCTL types both statically and
dynamically created ones, except for the SYSCTL NODE type and SYSCTLs
which belong to VNETs. A new flag, CTLFLAG_NOFETCH, has been added to
be used in the case a tunable sysctl has a custom initialisation
function allowing the sysctl to still be marked as a tunable. The
kernel SYSCTL API is mostly the same, with a few exceptions for some
special operations like iterating childrens of a static/extern SYSCTL
node. This operation should probably be made into a factored out
common macro, hence some device drivers use this. The reason for
changing the SYSCTL API was the need for a SYSCTL parent OID pointer
and not only the SYSCTL parent OID list pointer in order to quickly
generate the sysctl path. The motivation behind this patch is to avoid
parameter loading cludges inside the OFED driver subsystem. Instead of
adding special code to the OFED driver subsystem to post-load tunables
into dynamically created sysctls, we generalize this in the kernel.

Other changes:
- Corrected a possibly incorrect sysctl name from "hw.cbb.intr_mask"
to "hw.pcic.intr_mask".
- Removed redundant TUNABLE statements throughout the kernel.
- Some minor code rewrites in connection to removing not needed
TUNABLE statements.
- Added a missing SYSCTL_DECL().
- Wrapped two very long lines.
- Avoid malloc()/free() inside sysctl string handling, in case it is
called to initialize a sysctl from a tunable, hence malloc()/free() is
not ready when sysctls from the sysctl dataset are registered.
- Bumped FreeBSD version to indicate SYSCTL API change.

MFC after:	2 weeks
Sponsored by:	Mellanox Technologies
2014-06-27 16:33:43 +00:00
Robert Watson
4a14441044 Update kernel inclusions of capability.h to use capsicum.h instead; some
further refinement is required as some device drivers intended to be
portable over FreeBSD versions rely on __FreeBSD_version to decide whether
to include capability.h.

MFC after:	3 weeks
2014-03-16 10:55:57 +00:00
Gleb Smirnoff
b5c32cf481 Remove identical vnet sysctl handlers, and handle CTLFLAG_VNET
in the sysctl_root().

Note: SYSCTL_VNET_* macros can be removed as well. All is
  needed to virtualize a sysctl oid is set CTLFLAG_VNET on it.
  But for now keep macros in place to avoid large code churn.

Sponsored by:	Nginx, Inc.
2014-02-07 13:47:33 +00:00
Scott Long
f510415d84 Add a helpful message that can help point to why a sysctl tree removal failed
Obtained from:	Netflix
MFC after:	3 days
2013-08-09 01:04:44 +00:00
Marius Strobl
db9066f798 - Use strdup(9) instead of reimplementing it.
- Use __DECONST instead of strange casts.
- Reduce code duplication and simplify name2oid().

PR:		176373
Submitted by:	Christoph Mallon
MFC after:	1 week
2013-03-01 18:49:14 +00:00
Marius Strobl
18716f9f4b Update comments to reflect r246689. 2013-02-11 23:05:10 +00:00
Marius Strobl
bdc5f0172e Make SYSCTL_{LONG,QUAD,ULONG,UQUAD}(9) work as advertised and also handle
constant values.

Reviewed by:	kib
MFC after:	3 days
2013-02-11 21:50:00 +00:00
Alan Cox
5730afc9b6 Handle spurious page faults that may occur in no-fault sections of the
kernel.

When access restrictions are added to a page table entry, we flush the
corresponding virtual address mapping from the TLB.  In contrast, when
access restrictions are removed from a page table entry, we do not
flush the virtual address mapping from the TLB.  This is exactly as
recommended in AMD's documentation.  In effect, when access
restrictions are removed from a page table entry, AMD's MMUs will
transparently refresh a stale TLB entry.  In short, this saves us from
having to perform potentially costly TLB flushes.  In contrast,
Intel's MMUs are allowed to generate a spurious page fault based upon
the stale TLB entry.  Usually, such spurious page faults are handled
by vm_fault() without incident.  However, when we are executing
no-fault sections of the kernel, we are not allowed to execute
vm_fault().  This change introduces special-case handling for spurious
page faults that occur in no-fault sections of the kernel.

In collaboration with:	kib
Tested by:		gibbs (an earlier version)

I would also like to acknowledge Hiroki Sato's assistance in
diagnosing this problem.

MFC after:	1 week
2012-03-22 04:52:51 +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
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
Matthew D Fleming
3d08a76bbc Use a name instead of a magic number for kern_yield(9) when the priority
should not change.  Fetch the td_user_pri under the thread lock.  This
is probably not necessary but a magic number also seems preferable to
knowing the implementation details here.

Requested by:	Jason Behmer < jason DOT behmer AT isilon DOT com >
2011-05-13 05:27:58 +00:00
Jeff Roberson
e4cd31dd3c - Merge changes to the base system to support OFED. These include
a wider arg2 for sysctl, updates to vlan code, IFT_INFINIBAND,
   and other miscellaneous small features.
2011-03-21 09:40:01 +00:00
Matthew D Fleming
e7ceb1e99b Based on discussions on the svn-src mailing list, rework r218195:
- entirely eliminate some calls to uio_yeild() as being unnecessary,
   such as in a sysctl handler.

 - move should_yield() and maybe_yield() to kern_synch.c and move the
   prototypes from sys/uio.h to sys/proc.h

 - add a slightly more generic kern_yield() that can replace the
   functionality of uio_yield().

 - replace source uses of uio_yield() with the functional equivalent,
   or in some cases do not change the thread priority when switching.

 - fix a logic inversion bug in vlrureclaim(), pointed out by bde@.

 - instead of using the per-cpu last switched ticks, use a per thread
   variable for should_yield().  With PREEMPTION, the only reasonable
   use of this is to determine if a lock has been held a long time and
   relinquish it.  Without PREEMPTION, this is essentially the same as
   the per-cpu variable.
2011-02-08 00:16:36 +00:00
Matthew D Fleming
00f0e671ff Explicitly wire the user buffer rather than doing it implicitly in
sbuf_new_for_sysctl(9).  This allows using an sbuf with a SYSCTL_OUT
drain for extremely large amounts of data where the caller knows that
appropriate references are held, and sleeping is not an issue.

Inspired by:	rwatson
2011-01-27 00:34:12 +00:00
Matthew D Fleming
73d6f8516d Remove the CTLFLAG_NOLOCK as it seems to be both unused and
unfunctional.  Wiring the user buffer has only been done explicitly
since r101422.

Mark the kern.disks sysctl as MPSAFE since it is and it seems to have
been mis-using the NOLOCK flag.

Partially break the KPI (but not the KBI) for the sysctl_req 'lock'
field since this member should be private and the "REQ_LOCKED" state
seems meaningless now.
2011-01-26 22:48:09 +00:00
Matthew D Fleming
cbc134ad03 Introduce signed and unsigned version of CTLTYPE_QUAD, renaming
existing uses.  Rename sysctl_handle_quad() to sysctl_handle_64().
2011-01-19 23:00:25 +00:00
Matthew D Fleming
2fee06f087 Specify a CTLTYPE_FOO so that a future sysctl(8) change does not need
to rely on the format string.
2011-01-18 21:14:18 +00:00
Matthew D Fleming
dd6312a7c1 Fix uninitialized variable warning that shows on Tinderbox but not my
setup. (??)

Submitted by:	Michael Butler <imb at protected-networks dot net>
2010-11-29 21:53:21 +00:00
Matthew D Fleming
ccecef29d1 Do not hold the sysctl lock across a call to the handler. This fixes a
general LOR issue where the sysctl lock had no good place in the
hierarchy.  One specific instance is #284 on
http://sources.zabbadoz.net/freebsd/lor.html .

Reviewed by:	jhb
MFC after:	1 month
X-MFC-note:	split oid_refcnt field for oid_running to preserve KBI
2010-11-29 18:18:07 +00:00
Matthew D Fleming
d0bb6f258b Slightly modify the logic in sysctl_find_oid to reduce the indentation.
There should be no functional change.

MFC after:	3 days
2010-11-29 18:18:00 +00:00
Matthew D Fleming
5127ecb89c Use the SYSCTL_CHILDREN macro in kern_sysctl.c to help de-obfuscate the
code.

MFC after:	3 days
2010-11-29 18:17:53 +00:00
Matthew D Fleming
4e6571599b Re-add r212370 now that the LOR in powerpc64 has been resolved:
Add a drain function for struct sysctl_req, and use it for a variety
of handlers, some of which had to do awkward things to get a large
enough SBUF_FIXEDLEN buffer.

Note that some sysctl handlers were explicitly outputting a trailing
NUL byte.  This behaviour was preserved, though it should not be
necessary.

Reviewed by:    phk (original patch)
2010-09-16 16:13:12 +00:00
Matthew D Fleming
404a593e28 Revert r212370, as it causes a LOR on powerpc. powerpc does a few
unexpected things in copyout(9) and so wiring the user buffer is not
sufficient to perform a copyout(9) while holding a random mutex.

Requested by: nwhitehorn
2010-09-13 18:48:23 +00:00
Matthew D Fleming
dd67e2103c Add a drain function for struct sysctl_req, and use it for a variety of
handlers, some of which had to do awkward things to get a large enough
FIXEDLEN buffer.

Note that some sysctl handlers were explicitly outputting a trailing NUL
byte.  This behaviour was preserved, though it should not be necessary.

Reviewed by:	phk
2010-09-09 18:33:46 +00:00
Bjoern A. Zeeb
eb79e1c76e Make it possible to change the vnet sysctl variables on jails
with their own virtual network stack. Jails only inheriting a
network stack cannot change anything that cannot be changed from
within a prison.

Reviewed by:	rwatson, zec
Approved by:	re (kib)
2009-08-13 10:26:34 +00:00
Robert Watson
530c006014 Merge the remainder of kern_vimage.c and vimage.h into vnet.c and
vnet.h, we now use jails (rather than vimages) as the abstraction
for virtualization management, and what remained was specific to
virtual network stacks.  Minor cleanups are done in the process,
and comments updated to reflect these changes.

Reviewed by:	bz
Approved by:	re (vimage blanket)
2009-08-01 19:26:27 +00:00
Bjoern A. Zeeb
a08362ce46 sysctl_msec_to_ticks is used with both virtualized and
non-vrtiualized sysctls so we cannot used one common function.

Add a macro to convert the arg1 in the virtualized case to
vnet.h to not expose the maths to all over the code.

Add a wrapper for the single virtualized call, properly handling
arg1 and call the default implementation from there.

Convert the two over places to use the new macro.

Reviewed by:	rwatson
Approved by:	re (kib)
2009-07-21 21:58:55 +00:00
Robert Watson
eddfbb763d Build on Jeff Roberson's linker-set based dynamic per-CPU allocator
(DPCPU), as suggested by Peter Wemm, and implement a new per-virtual
network stack memory allocator.  Modify vnet to use the allocator
instead of monolithic global container structures (vinet, ...).  This
change solves many binary compatibility problems associated with
VIMAGE, and restores ELF symbols for virtualized global variables.

Each virtualized global variable exists as a "reference copy", and also
once per virtual network stack.  Virtualized global variables are
tagged at compile-time, placing the in a special linker set, which is
loaded into a contiguous region of kernel memory.  Virtualized global
variables in the base kernel are linked as normal, but those in modules
are copied and relocated to a reserved portion of the kernel's vnet
region with the help of a the kernel linker.

Virtualized global variables exist in per-vnet memory set up when the
network stack instance is created, and are initialized statically from
the reference copy.  Run-time access occurs via an accessor macro, which
converts from the current vnet and requested symbol to a per-vnet
address.  When "options VIMAGE" is not compiled into the kernel, normal
global ELF symbols will be used instead and indirection is avoided.

This change restores static initialization for network stack global
variables, restores support for non-global symbols and types, eliminates
the need for many subsystem constructors, eliminates large per-subsystem
structures that caused many binary compatibility issues both for
monitoring applications (netstat) and kernel modules, removes the
per-function INIT_VNET_*() macros throughout the stack, eliminates the
need for vnet_symmap ksym(2) munging, and eliminates duplicate
definitions of virtualized globals under VIMAGE_GLOBALS.

Bump __FreeBSD_version and update UPDATING.

Portions submitted by:  bz
Reviewed by:            bz, zec
Discussed with:         gnn, jamie, jeff, jhb, julian, sam
Suggested by:           peter
Approved by:            re (kensmith)
2009-07-14 22:48:30 +00:00
Bjoern A. Zeeb
ebd8672cc3 Add explicit includes for jail.h to the files that need them and
remove the "hidden" one from vimage.h.
2009-06-17 15:01:01 +00:00
Jamie Gritton
9ed47d01eb Get vnets from creds instead of threads where they're available, and from
passed threads instead of curthread.

Reviewed by:	zec, julian
Approved by:	bz (mentor)
2009-06-15 19:01:53 +00:00
Robert Watson
bcf11e8d00 Move "options MAC" from opt_mac.h to opt_global.h, as it's now in GENERIC
and used in a large number of files, but also because an increasing number
of incorrect uses of MAC calls were sneaking in due to copy-and-paste of
MAC-aware code without the associated opt_mac.h include.

Discussed with:	pjd
2009-06-05 14:55:22 +00:00
Dag-Erling Smørgrav
433e2f4763 Remove do-nothing code that was required to dirty the old buffer on Alpha.
Coverity ID:	838
Approved by:	jhb, alc
2009-05-15 21:34:58 +00:00
Konstantin Belousov
6b72d8db47 Revert r192094. The revision caused problems for sysctl(3) consumers
that expect that oldlen is filled with required buffer length even when
supplied buffer is too short and returned error is ENOMEM.

Redo the fix for kern.proc.filedesc, by reverting the req->oldidx when
remaining buffer space is too short for the current kinfo_file structure.
Also, only ignore ENOMEM. We have to convert ENOMEM to no error condition
to keep existing interface for the sysctl, though.

Reported by:	ed, Florian Smeets <flo kasimir com>
Tested by:	pho
2009-05-15 14:41:44 +00:00
John Baldwin
3e829b18d6 - Use a separate sx lock to try to limit the number of concurrent userland
sysctl requests to avoid wiring too much user memory.  Only grab this
  lock if the user's old buffer is larger than a page as a tradeoff to
  allow more concurrency for common small requests.
- Just use a shared lock on the sysctl tree for user sysctl requests now.

MFC after:	1 week
2009-05-14 22:01:32 +00:00
Konstantin Belousov
e401a6a54e Do not advance req->oldidx when sysctl_old_user returning an
error due to copyout failure or short buffer.

The later breaks the usermode iterators of the sysctl results that pack
arbitrary number of variable-sized structures. Iterator expects that
kernel filled exactly oldlen bytes, and tries to interpret half-filled
or garbage structure at the end of the buffer. In particular,
kinfo_getfile(3) segfaulted.

Reported and tested by:	pho
MFC after:	3 weeks
2009-05-14 10:54:57 +00:00
Marko Zec
f6dfe47a14 Permit buiding kernels with options VIMAGE, restricted to only a single
active network stack instance.  Turning on options VIMAGE at compile
time yields the following changes relative to default kernel build:

1) V_ accessor macros for virtualized variables resolve to structure
fields via base pointers, instead of being resolved as fields in global
structs or plain global variables.  As an example, V_ifnet becomes:

    options VIMAGE:          ((struct vnet_net *) vnet_net)->_ifnet
    default build:           vnet_net_0._ifnet
    options VIMAGE_GLOBALS:  ifnet

2) INIT_VNET_* macros will declare and set up base pointers to be used
by V_ accessor macros, instead of resolving to whitespace:

    INIT_VNET_NET(ifp->if_vnet); becomes

    struct vnet_net *vnet_net = (ifp->if_vnet)->mod_data[VNET_MOD_NET];

3) Memory for vnet modules registered via vnet_mod_register() is now
allocated at run time in sys/kern/kern_vimage.c, instead of per vnet
module structs being declared as globals.  If required, vnet modules
can now request the framework to provide them with allocated bzeroed
memory by filling in the vmi_size field in their vmi_modinfo structures.

4) structs socket, ifnet, inpcbinfo, tcpcb and syncache_head are
extended to hold a pointer to the parent vnet.  options VIMAGE builds
will fill in those fields as required.

5) curvnet is introduced as a new global variable in options VIMAGE
builds, always pointing to the default and only struct vnet.

6) struct sysctl_oid has been extended with additional two fields to
store major and minor virtualization module identifiers, oid_v_subs and
oid_v_mod.  SYSCTL_V_* family of macros will fill in those fields
accordingly, and store the offset in the appropriate vnet container
struct in oid_arg1.
In sysctl handlers dealing with virtualized sysctls, the
SYSCTL_RESOLVE_V_ARG1() macro will compute the address of the target
variable and make it available in arg1 variable for further processing.

Unused fields in structs vnet_inet, vnet_inet6 and vnet_ipfw have
been deleted.

Reviewed by:	bz, rwatson
Approved by:	julian (mentor)
2009-04-30 13:36:26 +00:00
John Baldwin
a56be37e68 Add a new type of KTRACE record for sysctl(3) invocations. It uses the
internal sysctl_sysctl_name() handler to map the MIB array to a string
name and logs this name in the trace log.  This can be useful to see
exactly which sysctls a thread is invoking.

MFC after:	1 month
2009-03-11 21:48:36 +00:00