implement shm_open(2) and shm_unlink(2) in the kernel:
- Each shared memory file descriptor is associated with a swap-backed vm
object which provides the backing store. Each descriptor starts off with
a size of zero, but the size can be altered via ftruncate(2). The shared
memory file descriptors also support fstat(2). read(2), write(2),
ioctl(2), select(2), poll(2), and kevent(2) are not supported on shared
memory file descriptors.
- shm_open(2) and shm_unlink(2) are now implemented as system calls that
manage shared memory file descriptors. The virtual namespace that maps
pathnames to shared memory file descriptors is implemented as a hash
table where the hash key is generated via the 32-bit Fowler/Noll/Vo hash
of the pathname.
- As an extension, the constant 'SHM_ANON' may be specified in place of the
path argument to shm_open(2). In this case, an unnamed shared memory
file descriptor will be created similar to the IPC_PRIVATE key for
shmget(2). Note that the shared memory object can still be shared among
processes by sharing the file descriptor via fork(2) or sendmsg(2), but
it is unnamed. This effectively serves to implement the getmemfd() idea
bandied about the lists several times over the years.
- The backing store for shared memory file descriptors are garbage
collected when they are not referenced by any open file descriptors or
the shm_open(2) virtual namespace.
Submitted by: dillon, peter (previous versions)
Submitted by: rwatson (I based this on his version)
Reviewed by: alc (suggested converting getmemfd() to shm_open())
- Introduce a finit() which is used to initailize the fields of struct file
in such a way that the ops vector is only valid after the data, type,
and flags are valid.
- Protect f_flag and f_count with atomic operations.
- Remove the global list of all files and associated accounting.
- Rewrite the unp garbage collection such that it no longer requires
the global list of all files and instead uses a list of all unp sockets.
- Mark sockets in the accept queue so we don't incorrectly gc them.
Tested by: kris, pho
Without it, code has two problems:
- behaviour of the old and new [l]stat are different with regard of
the /compat/linux
- directly accessing the userspace data from the kernel asks for
the panics.
Reported and tested by: Peter Holm
Reviewed by: rdivacky
MFC after: 3 days
for that argument. This will allow DDB to detect the broad category of
reason why the debugger has been entered, which it can use for the
purposes of deciding which DDB script to run.
Assign approximate why values to all current consumers of the
kdb_enter() interface.
January 1, 1601. The 1601 - 1970 period was in seconds rather than 100ns
units.
Remove duplication by having NdisGetCurrentSystemTime call ntoskrnl_time.
per-cpu area. cp_time[] goes away and a new function creates a merged
cp_time-like array for things like linprocfs, sysctl etc. The
atomic ops for updating cp_time[] in statclock go away, and the scope
of the thread lock is reduced.
sysctl kern.cp_time returns a backwards compatible cp_time[] array.
A new kern.cp_times sysctl returns the individual per-cpu stats.
I have pending changes to make top and vmstat optionally show per-cpu
stats.
I'm very aware that there are something like 5 or 6 other versions "out
there" for doing this - but none were handy when I needed them.
I did merge my changes with John Baldwin's, and ended up replacing a
few chunks of my stuff with his, and stealing some other code.
Reviewed by: jhb
Partly obtained from: jhb
LINUX_SIOCGIFCOUNT just returns 0 since it is not implemented in the
Linux 2.6.16.
LINUX_SIOCGIFINDEX/LINUX_SIOGIFINDEX are mapped to the FreeBSD native
SIOCGIFINDEX.
Tested by: Peter Kostouros <kpeter@melbpc.org.au>
Reviewed by: brooks, rpaulo (on net@)
Submitted by: rdivacky
MFC after: 1 week
characters (mostly "&"). Because top(1) shows only first six characters of
wait channel, without this change we saw only one meaningful character.
Requested by: kris & others
MFC after: 1 week
silent NULL pointer dereference in the i386 and sparc64 pmap_pinit()
when the kmem_alloc_nofault() failed to allocate address space. Both
functions now return error instead of panicing or dereferencing NULL.
As consequence, vmspace_exec() and vmspace_unshare() returns the errno
int. struct vmspace arg was added to vm_forkproc() to avoid dealing
with failed allocation when most of the fork1() job is already done.
The kernel stack for the thread is now set up in the thread_alloc(),
that itself may return NULL. Also, allocation of the first process
thread is performed in the fork1() to properly deal with stack
allocation failure. proc_linkup() is separated into proc_linkup()
called from fork1(), and proc_linkup0(), that is used to set up the
kernel process (was known as swapper).
In collaboration with: Peter Holm
Reviewed by: jhb
from Mac OS X Leopard--rationalize naming for entry points to
the following general forms:
mac_<object>_<method/action>
mac_<object>_check_<method/action>
The previous naming scheme was inconsistent and mostly
reversed from the new scheme. Also, make object types more
consistent and remove spaces from object types that contain
multiple parts ("posix_sem" -> "posixsem") to make mechanical
parsing easier. Introduce a new "netinet" object type for
certain IPv4/IPv6-related methods. Also simplify, slightly,
some entry point names.
All MAC policy modules will need to be recompiled, and modules
not updates as part of this commit will need to be modified to
conform to the new KPI.
Sponsored by: SPARTA (original patches against Mac OS X)
Obtained from: TrustedBSD Project, Apple Computer
to kproc_xxx as they actually make whole processes.
Thos makes way for us to add REAL kthread_create() and friends
that actually make theads. it turns out that most of these
calls actually end up being moved back to the thread version
when it's added. but we need to make this cosmetic change first.
I'd LOVE to do this rename in 7.0 so that we can eventually MFC the
new kthread_xxx() calls.
3 arguments, but we had forgotten the second argument. Also make the
Linux statfs64 struct depend on the architecture because it has an
extra 4 bytes padding on amd64 compared to i386.
The three argument fix is from David Taylor, the struct statfs64
stuff is my fault. With this patch I can install i386 Linux matlab
on an amd64 machine.
Submitted by: David Taylor <davidt_at_yadt.co.uk>
Approved by: re (kensmith)
64-bit counters) to a 4.x statfs structure (with long-sized counters).
- For block counters, we scale up the block size sufficiently large so
that the resulting block counts fit into a the long-sized (long for the
ABI, so 32-bit in freebsd32) counters. In 4.x the NFS client's statfs
VOP did this already. This can lie about the block size to 4.x binaries,
but it presents a more accurate picture of the ratios of free and
available space.
- For non-block counters, fix the freebsd32 stats converter to cap the
values at INT32_MAX rather than losing the upper 32-bits to match the
behavior of the 4.x statfs conversion routine in vfs_syscalls.c
Approved by: re (kensmith)
with Linux 2.6 emulation. This shall be reimplemented once FreeBSD gets
native scheduler affinity syscalls.
Submitted by: rdivacky
Reviewed by: jkim
Sponsored by: Google Summer of Code 2007
Approved by: re (kensmith)
previously conditionally acquired Giant based on debug.mpsafenet. As that
has now been removed, they are no longer required. Removing them
significantly simplifies error-handling in the socket layer, eliminated
quite a bit of unwinding of locking in error cases.
While here clean up the now unneeded opt_net.h, which previously was used
for the NET_WITH_GIANT kernel option. Clean up some related gotos for
consistency.
Reviewed by: bz, csjp
Tested by: kris
Approved by: re (kensmith)
be woken up by kthread_exit. This is racey and in some cases the kthread will
exit before ndis gets around to sleep so it will be stuck indefinitely. This
change reuses the kq_exit variable to indicate that the thread has gone and
will loop on tsleep with a timeout waiting for it. If the kthread has already
exited then it will not sleep at all.
Approved by: re (rwatson)
kernels exposed by the recent fixes to resource limits for 32-bit processes
on 64-bit kernels:
- Let ABIs expose their maximum stack size via a new pointer in sysentvec
and use that in preference to maxssiz during exec() rather than always
using maxssiz for all processses.
- Apply the ABI's limit fixup to the previous stack size when adjusting
RLIMIT_STACK to determine if the existing mapping for the stack needs to
be grown or shrunk (as well as how much it should be grown or shrunk).
Approved by: re (kensmith)
