adjusted via sysctl. file systems that have hash tables which are
sized based on the value of this variable now resize those hash tables
using the new value. the max number of FFS softdeps is also recalculated.
convert various file systems to use the <sys/queue.h> macros for
their hash tables.
for FreeBSD project. Besides huge speed boost compared with socketpair-based
pipes, this implementation also uses pagable kernel memory instead of mbufs.
Significant differences to FreeBSD version:
* uses uvm_loan() facility for direct write
* async/SIGIO handling correct also for sync writer, async reader
* limits settable via sysctl, amountpipekva and nbigpipes available via sysctl
* pipes are unidirectional - this is enforced on file descriptor level
for now only, the code would be updated to take advantage of it
eventually
* uses lockmgr(9)-based locks instead of home brew variant
* scatter-gather write is handled correctly for direct write case, data
is transferred by PIPE_DIRECT_CHUNK bytes maximum, to avoid running out of kva
All FreeBSD/NetBSD specific code is within appropriate #ifdef, in preparation
to feed changes back to FreeBSD tree.
This pipe implementation is optional for now, add 'options NEW_PIPE'
to your kernel config to use it.
only signal handler array sharable between threads
move other random signal stuff from struct proc to struct sigctx
This addresses kern/10981 by Matthew Orgass.
to support arbitrary number of ptys without need of kernel recompile
(the extra device special files in /dev/ still need to be created, of course)
upper limit of supported ptys is controlled via new sysctl variable
kern.maxptys (KERN_MAXPTYS), which is raise-only and defaults to 512.
instead test for (p->p_flag & I_INMEM), and don't access the U-area
(via p->p_stats) if that bit is clear. Fixes the hangs people have
seen when the system is paging and the user runs top/ps/w.
vslock the user pages for the data being copied out to userspace,
so that we won't sleep while holding a lock in case we need to
fault the pages in.
- Sprinkle some const and ANSI'ify some things while here.
* Handle KERN_PROC_SESSION that has been defined in <sys/sysctl.h> from
day one.
* Add handlers for KERN_PROC_GID and KERN_PROC_RGID.
* If "op" doesn't valid, return EINVAL.
"KERN_SYSVIPC_SEM_INFO" and "KERN_SYSVIPC_SHM_INFO" to return the
info and data structures for the relevent SysV IPC types. The return
structures use fixed-size types and should be compat32 safe. All
user-visible changes are protected with
#if !defined(_POSIX_C_SOURCE) && !defined(_XOPEN_SOURCE)
Make all variable declarations extern in msg.h, sem.h and shm.h and
add relevent variable declarations to sysv_*.c and remove unneeded
header files from those .c files.
Make compat14 SysV IPC conversion functions and sysctl_file() static.
Change the data pointer to "void *" in sysctl_clockrate(),
sysctl_ntptime(), sysctl_file() and sysctl_doeproc().
p_cpu member to struct proc. Use this in certain places when
accessing scheduler state, etc. For the single-processor case,
just initialize p_cpu in fork1() to avoid having to set it in the
low-level context switch code on platforms which will never have
multiprocessing.
While I'm here, comment a few places where there are known issues
for the SMP implementation.
by Anders Magnusson.
Honor elem_count in the KERN_PROC2 case, as well as overall buffer
space. The only user-land code to use this set the elem_count to
"buffer_space / elem_size", so we've had no incorrect behaviour to date.
errors from ps(1) and some other kernel grovellers, and return some
data that has previously only been accessable with /dev/kmem read
access. The sysctls are:
+ KERN_PROC2 - return an array of fixed sized "struct kinfo_proc2"
structures that contain most of the useful user-level data in
"struct proc" and "struct user". The sysctl also takes the size of
each element, so that if "struct kinfo_proc2" grows over time old
binaries will still be able to request a fixed size amount of data.
+ KERN_PROC_ARGS - return the argv or envv for a particular process id.
envv will only be returned if the process has the same user id as the
requestor or if the requestor is root.
+ KERN_FSCALE - return the current kernel fixpt scale factor.
+ KERN_CCPU - return the scheduler exponential decay value.
+ KERN_CP_TIME - return cpu time state counters.
With input and suggestions from many people on tech-kern.
cause a core to drop, and whether the core dropped, or, if it did
not, why not (i.e. error number). Logs process ID, name, signal that
hit it, and whether the core dump was successful.
logging only happens if kern_logsigexit is non-zero, and it can be
changed by the new sysctl(3) value KERN_LOGSIGEXIT. The name of this
sysctl and its function are taken from FreeBSD, at the suggestion
of Greg Woods in PR 6224. Default behavior is zero for a normal
kernel, and one for a kernel compiled with DIAGNOSTIC.
are handled as arrays; that is, a truncated old value is returned, alongside
with ENOMEM, if the buffer is too small.
- in all int, quad, and single struct cases, and all specials handled inside
this file, oldlenp semantics are now as documented in the manual page, that
is, a NULL oldp, but non-NULL oldlenp returns the needed size
[I had to change the oldlenp handling, so I thought I should make it as
advertized. Formerly, the subroutines would not know when a NULL oldlenp
was passed, do the work anyway, and the value would be thrown away.]
This is needed as a first step to make gethostname() and getdomainname()
conform to its own manual page and SUSV2. (See pr 7836 by Simon Burge)
be used uninitialized when name[0] != PROC_CURPROC and
proclists[0]->pd_list == NULL; actually, this can never happen
(proclists[0] == &allproc), but the compiler can not know this, so it
complains
core filename format, which allow to change the name of the core dump,
and to relocate it in a directory. Credits to Bill Sommerfeld for giving me
the idea :)
The default core filename format can be changed by options DEFCORENAME and/or
kern.defcorename
Create a new sysctl tree, proc, which holds per-process values (for now
the corename format, and resources limits). Process is designed by its pid
at the second level name. These values are inherited on fork, and the corename
fomat is reset to defcorename on suid/sgid exec.
Create a p_sugid() function, to take appropriate actions on suid/sgid
exec (for now set the P_SUGID flag and reset the per-proc corename).
Adjust dosetrlimit() to allow changing limits of one proc by another, with
credential controls.
calls to reflect this. Also, block statclock rather than softclock during
in the proclist locking functions, to address a problem reported on
current-users by Sean Doran.
write lock when doing PID allocation, and during the process exit path.
Use a read lock every where else, including within schedcpu() (interrupt
context). Note that holding the write lock implies blocking schedcpu()
from running (blocks softclock).
PID allocation is now MP-safe.
Note this actually fixes a bug on single processor systems that was probably
extremely difficult to tickle; it was possible that schedcpu() would run
off a bad pointer if the right clock interrupt happened to come in the
middle of a LIST_INSERT_HEAD() or LIST_REMOVE() to/from allproc.
and PID allocation MP-safe. A new process state is added: SDEAD. This
state indicates that a process is dead, but not yet a zombie (has not
yet been processed by the process reaper).
SDEAD processes exist on both the zombproc list (via p_list) and deadproc
(via p_hash; the proc has been removed from the pidhash earlier in the exit
path). When the reaper deals with a process, it changes the state to
SZOMB, so that wait4 can process it.
Add a P_ZOMBIE() macro, which treats a proc in SZOMB or SDEAD as a zombie,
and update various parts of the kernel to reflect the new state.
lukem