Require both the prison mutex and allprison_lock when pr_ref or
pr_uref go to/from zero. Adding a non-first or removing a non-last
reference remain lock-free. This means that a shared hold on
allprison_lock is sufficient for prison_isalive() to be useful, which
removes a number of cases of lock/check/unlock on the prison mutex.
Expand the locking in kern_jail_set() to keep allprison_lock held
exclusive until the new prison is valid, thus making invalid prisons
invisible to any thread holding allprison_lock (except of course the
one creating or destroying the prison). This renders prison_isvalid()
nearly redundant, now used only in asserts.
Differential Revision: https://reviews.freebsd.org/D28419
Differential Revision: https://reviews.freebsd.org/D28458
prison_isvalid() checks if a prison record can be used at all, i.e.
pr_ref > 0. This filters out prisons that aren't fully created, and
those that are either in the process of being dismantled, or will be
at the next opportunity. While the check for pr_ref > 0 is simple
enough to make without a convenience function, this prepares the way
for other measures of prison validity.
prison_isalive() checks not only validity as far as the useablity of
the prison structure, but also whether the prison is visible to user
space. It replaces a test for pr_uref > 0, which is currently only
used within kern_jail.c, and not often there.
Both of these functions also assert that either the prison mutex or
allprison_lock is held, since it's generally the case that unlocked
prisons aren't guaranteed to remain useable for any length of time.
This isn't entirely true, for example a thread can assume its own
prison is good, but most exceptions will exist inside of kern_jail.c.
Alter shmget_allocate_segment and shmget_existing to take the values
they want from struct shmget_args rather than passing the struct
around. In general, uap structures should only be the interface to
sys_<foo> functions.
This makes on small functional change and records the allocated space
rather than the requested space. If this turns out to be a problem (e.g.
if software tries to find undersized segments by exact size rather than
using keys), we can correct that easily.
Reviewed by: kib
Obtained from: CheriBSD
MFC after: 1 week
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D27077
Copy the CP, PTRIN, etc macros from freebsd32.h into a sys/abi_compat.h
and replace existing definitation with includes where required. This
eliminates duplicate code and allows Linux and FreeBSD compatability
headers to be included in the same files.
Input from: cem, jhb
Obtained from: CheriBSD
MFC after: 2 weeks
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D24275
reudundant complicated checks and additional locking required only for
anonymous memory. Introduce vm_object_allocate_anon() to create these
objects. DEFAULT and SWAP objects now have the correct settings for
non-anonymous consumers and so individual consumers need not modify the
default flags to create super-pages and avoid ONEMAPPING/NOSPLIT.
Reviewed by: alc, dougm, kib, markj
Tested by: pho
Differential Revision: https://reviews.freebsd.org/D22119
Based on the description in Linux man page.
Reviewed by: markj, ngie (previous version)
Sponsored by: Mellanox Technologies
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D18837
This also removes a lot of #ifdefs and cleans up a warning when the
AUDIT kernel option is defined, but neither KDTRACE_HOOKS nor MAC are.
Reported and tested by: danger
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
opt_compat.h is mentioned in nearly 180 files. In-progress network
driver compabibility improvements may add over 100 more so this is
closer to "just about everywhere" than "only some files" per the
guidance in sys/conf/options.
Keep COMPAT_LINUX32 in opt_compat.h as it is confined to a subset of
sys/compat/linux/*.c. A fake _COMPAT_LINUX option ensure opt_compat.h
is created on all architectures.
Move COMPAT_LINUXKPI to opt_dontuse.h as it is only used to control the
set of compiled files.
Reviewed by: kib, cem, jhb, jtl
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14941
It is random collection of fixes for issues not yet corrected,
reported at https://tsyrklevi.ch/clang_analyzer/freebsd_013017/. Many
issues from that list were already corrected. Most of them are for
compat32, old compat32 or affect both primary host ABI and compat32.
The freebsd32_kldstat(), for instance, was already fixed by using
malloc(M_ZERO). Patch includes correction to report the supplied
version back, which is just pedantic.
Reviewed by: brooks, emaste (previous version)
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D14868
The description of kern.ipc.shmsegs was wrong since 2005. I updated the
others (which were more correct) to match.
PR: 225933
Reviewed by: cem
MFC after: 3 days
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14391
Stop leaking kernel pointers though theses sysctls and make sure that the
padding in the structures is zeroed on allocation to avoid other leaks.
Reviewed by: gordon, kib
Obtained from: CheriBSD
MFC after: 1 week
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D13459
Both files originated in NetBSD:
sysv_ipc.c CVS 1.9:
Most of their changes don't apply to us as we already have similar
changes. This is a better reference for future merges.
sysv_shm.c CVS 1.39:
Most of their changes don't apply to our code but interestingly this
revision merged our changes and is a better point for reference.
Move the VCS tags to the position recommended in our committers guide
(section 8),
No functional change.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
map the 'which' argument into a suitable audit event identifier for the
specific operation requested.
Obtained from: TrustedBSD Project
MFC after: 3 weeks
Sponsored by: DARPA, AFRL
It looks like our "struct shmid_ds::shm_nattch" deviates from the
standard in the sense that it is a signed integer, whereas POSIX
requires that it is unsigned, having a special type shmatt_t.
Patch up our native and 32-bit copies to use a new shmatt_t that is an
unsigned integer. As it's unsigned, we can relax the comparisons that
are performed on it. Leave the Linux, iBCS2, etc. copies of the
structure alone.
Reviewed by: ngie
Differential Revision: https://reviews.freebsd.org/D6655
This is a minor follow-up to r297422, prompted by a Coverity warning. (It's
not a real defect, just a code smell.) OSD slot array reservations are an
array of pointers (void **) but were cast to void* and back unnecessarily.
Keep the correct type from reservation to use.
osd.9 is updated to match, along with a few trivial igor fixes.
Reported by: Coverity
CID: 1353811
Sponsored by: EMC / Isilon Storage Division
sysvmsg, sysvsem, and sysvshm, with the following bahavior:
inherit: allow full access to the IPC primitives. This is the same as
the current setup with allow.sysvipc is on. Jails and the base system
can see (and moduly) each other's objects, which is generally considered
a bad thing (though may be useful in some circumstances).
disable: all no access, same as the current setup with allow.sysvipc off.
new: A jail may see use the IPC objects that it has created. It also
gets its own IPC key namespace, so different jails may have their own
objects using the same key value. The parent jail (or base system) can
see the jail's IPC objects, but not its keys.
PR: 48471
Submitted by: based on work by kikuchan98@gmail.com
MFC after: 5 days
rounddown2 tends to produce longer lines than the original code
and when the code has a high indentation level it was not really
advantageous to do the replacement.
This tries to strike a balance between readability using the macros
and flexibility of having the expressions, so not everything is
converted.
This removes the need for manually changing this flag for Google Chrome
users. It also improves compatibility with Linux applications running under
Linuxulator compatibility layer, and possibly also helps in porting software
from Linux.
Generally speaking, the flag allows applications to create the shared memory
segment, attach it, remove it, and then continue to use it and to reattach it
later. This means that the kernel will automatically "clean up" after the
application exits.
It could be argued that it's against POSIX. However, SUSv3 says this
about IPC_RMID: "Remove the shared memory identifier specified by shmid from
the system and destroy the shared memory segment and shmid_ds data structure
associated with it." From my reading, we break it in any case by deferring
removal of the segment until it's detached; we won't break it any more
by also deferring removal of the identifier.
This is the behaviour exhibited by Linux since... probably always, and
also by OpenBSD since the following commit:
revision 1.54
date: 2011/10/27 07:56:28; author: robert; state: Exp; lines: +3 -8;
Allow segments to be used even after they were marked for deletion with
the IPC_RMID flag.
This is permitted as an extension beyond the standards and this is similar
to what other operating systems like linux do.
MFC after: 1 month
Relnotes: yes
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D3603
Use the same scheme implemented to manage credentials.
Code needing to look at process's credentials (as opposed to thred's) is
provided with *_proc variants of relevant functions.
Places which possibly had to take the proc lock anyway still use the proc
pointer to access limits.
The point of this is to be able to add RACCT (with RACCT_DISABLED)
to GENERIC, to avoid having to rebuild the kernel to use rctl(8).
Differential Revision: https://reviews.freebsd.org/D2369
Reviewed by: kib@
MFC after: 1 month
Relnotes: yes
Sponsored by: The FreeBSD Foundation
- Use real locking, replace Giant with global sx protecting the
subsystem. Since the subsystem' lock is no longer dropped during
the sleepsk, remove not needed SHMSEG_WANTED segment flag, and
revert r278963.
- To do proper code simplification possible after the change of the
lock, restructure several functions into _locked body and
originally-named wrapper which calls into _locked variant. This
allows to eliminate the 'goto done2' spread over the code.
- Merge shm_find_segment_by_shmid() and shm_find_segment_by_shmidx().
- Consistently change all function prototypes to ANSI C.
Reviewed by: mjg (who has earlier version of the similar patch to
introduce real locking)
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
The kernel tracks syscall users so that modules can safely unregister them.
But if the module is not unloadable or was compiled into the kernel, there is
no need to do this.
Achieve this by adding SY_THR_STATIC_KLD macro which expands to SY_THR_STATIC
during kernel build and 0 otherwise.
Reviewed by: kib (previous version)
MFC after: 2 weeks
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
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
an address in the first 2GB of the process's address space. This flag should
have the same semantics as the same flag on Linux.
To facilitate this, add a new parameter to vm_map_find() that specifies an
optional maximum virtual address. While here, fix several callers of
vm_map_find() to use a VMFS_* constant for the findspace argument instead of
TRUE and FALSE.
Reviewed by: alc
Approved by: re (kib)
- Add a new address space allocation method (VMFS_OPTIMAL_SPACE) for
vm_map_find() that will try to alter the alignment of a mapping to match
any existing superpage mappings of the object being mapped. If no
suitable address range is found with the necessary alignment,
vm_map_find() will fall back to using the simple first-fit strategy
(VMFS_ANY_SPACE).
- Change mmap() without MAP_FIXED, shmat(), and the GEM mapping ioctl to
use VMFS_OPTIMAL_SPACE instead of VMFS_ANY_SPACE.
Reviewed by: alc (earlier version)
MFC after: 2 weeks
future further optimizations where the vm_object lock will be held
in read mode most of the time the page cache resident pool of pages
are accessed for reading purposes.
The change is mostly mechanical but few notes are reported:
* The KPI changes as follow:
- VM_OBJECT_LOCK() -> VM_OBJECT_WLOCK()
- VM_OBJECT_TRYLOCK() -> VM_OBJECT_TRYWLOCK()
- VM_OBJECT_UNLOCK() -> VM_OBJECT_WUNLOCK()
- VM_OBJECT_LOCK_ASSERT(MA_OWNED) -> VM_OBJECT_ASSERT_WLOCKED()
(in order to avoid visibility of implementation details)
- The read-mode operations are added:
VM_OBJECT_RLOCK(), VM_OBJECT_TRYRLOCK(), VM_OBJECT_RUNLOCK(),
VM_OBJECT_ASSERT_RLOCKED(), VM_OBJECT_ASSERT_LOCKED()
* The vm/vm_pager.h namespace pollution avoidance (forcing requiring
sys/mutex.h in consumers directly to cater its inlining functions
using VM_OBJECT_LOCK()) imposes that all the vm/vm_pager.h
consumers now must include also sys/rwlock.h.
* zfs requires a quite convoluted fix to include FreeBSD rwlocks into
the compat layer because the name clash between FreeBSD and solaris
versions must be avoided.
At this purpose zfs redefines the vm_object locking functions
directly, isolating the FreeBSD components in specific compat stubs.
The KPI results heavilly broken by this commit. Thirdy part ports must
be updated accordingly (I can think off-hand of VirtualBox, for example).
Sponsored by: EMC / Isilon storage division
Reviewed by: jeff
Reviewed by: pjd (ZFS specific review)
Discussed with: alc
Tested by: pho
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)
won't happen before 9.0. This commit adds "#ifdef RACCT" around all the
"PROC_LOCK(p); racct_whatever(p, ...); PROC_UNLOCK(p)" instances, in order
to avoid useless locking/unlocking in kernels built without "options RACCT".
