Commit Graph

210 Commits

Author SHA1 Message Date
Alan Cox
75337a5677 Guard against address wrap in kernacc(). Otherwise, a program accessing a
bad address range through /dev/kmem can panic the machine.

Submitted by: Mark W. Krentel
Reported by: Kris Kennaway
MFC after: 1 week
2005-01-22 19:21:29 +00:00
Warner Losh
60727d8b86 /* -> /*- for license, minor formatting changes 2005-01-07 02:29:27 +00:00
David Schultz
6004362e66 Don't include sys/user.h merely for its side-effect of recursively
including other headers.
2004-11-27 06:51:39 +00:00
David Schultz
9799b417d5 Disable U area swapping and remove the routines that create, destroy,
copy, and swap U areas.

Reviewed by:	arch@
2004-11-20 02:29:00 +00:00
Alan Cox
d19ef81437 The synchronization provided by vm object locking has eliminated the
need for most calls to vm_page_busy().  Specifically, most calls to
vm_page_busy() occur immediately prior to a call to vm_page_remove().
In such cases, the containing vm object is locked across both calls.
Consequently, the setting of the vm page's PG_BUSY flag is not even
visible to other threads that are following the synchronization
protocol.

This change (1) eliminates the calls to vm_page_busy() that
immediately precede a call to vm_page_remove() or functions, such as
vm_page_free() and vm_page_rename(), that call it and (2) relaxes the
requirement in vm_page_remove() that the vm page's PG_BUSY flag is
set.  Now, the vm page's PG_BUSY flag is set only when the vm object
lock is released while the vm page is still in transition.  Typically,
this is when it is undergoing I/O.
2004-11-03 20:17:31 +00:00
Alan Cox
ddf4bb37c8 Use VM_ALLOC_NOBUSY instead of calling vm_page_wakeup(). 2004-10-24 18:46:32 +00:00
David Schultz
8daa8c602a The zone from which proc structures are allocated is marked
UMA_ZONE_NOFREE to guarantee type stability, so proc_fini() should
never be called.  Move an assertion from proc_fini() to proc_dtor()
and garbage-collect the rest of the unreachable code.  I have retained
vm_proc_dispose(), since I consider its disuse a bug.
2004-09-19 18:34:17 +00:00
Alan Cox
94ddc7076d Push Giant deep into vm_forkproc(), acquiring it only if the process has
mapped System V shared memory segments (see shmfork_myhook()) or requires
the allocation of an ldt (see vm_fault_wire()).
2004-09-03 05:11:32 +00:00
Alan Cox
9be60284a6 Giant is no longer required by vm_waitproc() and vmspace_exitfree().
Eliminate it acquisition and release around vm_waitproc() in kern_wait().
2004-07-30 20:31:02 +00:00
Alan Cox
1a276a3f91 - Use atomic ops for updating the vmspace's refcnt and exitingcnt.
- Push down Giant into shmexit().  (Giant is acquired only if the vmspace
   contains shm segments.)
 - Eliminate the acquisition of Giant from proc_rwmem().
 - Reduce the scope of Giant in exit1(), uncovering the destruction of the
   address space.
2004-07-27 03:53:41 +00:00
John Baldwin
d202e0cccc - Don't use a variable to point to the user area that we only use once.
Just use p2->p_uarea directly instead.
- Remove an old and mostly bogus assertion regarding p2->p_sigacts.
- Use RANGEOF macro ala fork1() to clean up bzero/bcopy of p_stats.
2004-07-02 03:45:07 +00:00
David Schultz
17d9d0d049 Update a stale comment. The heuristic to swap processes out based on
the number of pages already paged out was broken in rev 1.10 and
removed in rev 1.11.
2004-06-27 01:58:12 +00:00
Julian Elischer
fa88511615 Nice, is a property of a process as a whole..
I mistakenly moved it to the ksegroup when breaking up the process
structure. Put it back in the proc structure.
2004-06-16 00:26:31 +00:00
Brian Feldman
d9b2500eef In r1.190, vslock() and vsunlock() were bogusly made to do a "user wire"
and a "system unwire."  Make this a "system wire" and "system unwire."

Reviewed by:	alc
2004-05-07 11:43:24 +00:00
Warner Losh
05eb3785e7 Remove advertising clause from University of California Regent's license,
per letter dated July 22, 1999.

Approved by: core
2004-04-06 20:15:37 +00:00
Don Lewis
bb734798af Make overflow/wraparound checking more robust and unbreak len=0 in
vslock(), mlock(), and munlock().

Reviewed by:	bde
2004-03-15 09:11:23 +00:00
Don Lewis
f0ea4612ef Style(9) changes.
Pointed out by:	bde
2004-03-15 06:43:51 +00:00
Don Lewis
ce8660e395 Revert to the original vslock() and vsunlock() API with the following
exceptions:
	Retain the recently added vslock() error return.

	The type of the len argument should be size_t, not u_int.

Suggested by:	bde
2004-03-15 06:42:40 +00:00
Alan Cox
fcffa790e9 Retire pmap_pinit2(). Alpha was the last platform that used it. However,
ever since alpha/alpha/pmap.c revision 1.81 introduced the list allpmaps,
there has been no reason for having this function on Alpha.  Briefly,
when pmap_growkernel() relied upon the list of all processes to find and
update the various pmaps to reflect a growth in the kernel's valid
address space, pmap_init2() served to avoid a race between pmap
initialization and pmap_growkernel().  Specifically, pmap_pinit2() was
responsible for initializing the kernel portions of the pmap and
pmap_pinit2() was called after the process structure contained a pointer
to the new pmap for use by pmap_growkernel().  Thus, an update to the
kernel's address space might be applied to the new pmap unnecessarily,
but an update would never be lost.
2004-03-07 21:06:48 +00:00
Don Lewis
169299398a Undo the merger of mlock()/vslock and munlock()/vsunlock() and the
introduction of kern_mlock() and kern_munlock() in
        src/sys/kern/kern_sysctl.c      1.150
        src/sys/vm/vm_extern.h          1.69
        src/sys/vm/vm_glue.c            1.190
        src/sys/vm/vm_mmap.c            1.179
because different resource limits are appropriate for transient and
"permanent" page wiring requests.

Retain the kern_mlock() and kern_munlock() API in the revived
vslock() and vsunlock() functions.

Combine the best parts of each of the original sets of implementations
with further code cleanup.  Make the mclock() and vslock()
implementations as similar as possible.

Retain the RLIMIT_MEMLOCK check in mlock().  Move the most strigent
test, which can return EAGAIN, last so that requests that have no
hope of ever being satisfied will not be retried unnecessarily.

Disable the test that can return EAGAIN in the vslock() implementation
because it will cause the sysctl code to wedge.

Tested by:	Cy Schubert <Cy.Schubert AT komquats.com>
2004-03-05 22:03:11 +00:00
Don Lewis
47934cef8f Split the mlock() kernel code into two parts, mlock(), which unpacks
the syscall arguments and does the suser() permission check, and
kern_mlock(), which does the resource limit checking and calls
vm_map_wire().  Split munlock() in a similar way.

Enable the RLIMIT_MEMLOCK checking code in kern_mlock().

Replace calls to vslock() and vsunlock() in the sysctl code with
calls to kern_mlock() and kern_munlock() so that the sysctl code
will obey the wired memory limits.

Nuke the vslock() and vsunlock() implementations, which are no
longer used.

Add a member to struct sysctl_req to track the amount of memory
that is wired to handle the request.

Modify sysctl_wire_old_buffer() to return an error if its call to
kern_mlock() fails.  Only wire the minimum of the length specified
in the sysctl request and the length specified in its argument list.
It is recommended that sysctl handlers that use sysctl_wire_old_buffer()
should specify reasonable estimates for the amount of data they
want to return so that only the minimum amount of memory is wired
no matter what length has been specified by the request.

Modify the callers of sysctl_wire_old_buffer() to look for the
error return.

Modify sysctl_old_user to obey the wired buffer length and clean up
its implementation.

Reviewed by:	bms
2004-02-26 00:27:04 +00:00
John Baldwin
91d5354a2c Locking for the per-process resource limits structure.
- struct plimit includes a mutex to protect a reference count.  The plimit
  structure is treated similarly to struct ucred in that is is always copy
  on write, so having a reference to a structure is sufficient to read from
  it without needing a further lock.
- The proc lock protects the p_limit pointer and must be held while reading
  limits from a process to keep the limit structure from changing out from
  under you while reading from it.
- Various global limits that are ints are not protected by a lock since
  int writes are atomic on all the archs we support and thus a lock
  wouldn't buy us anything.
- All accesses to individual resource limits from a process are abstracted
  behind a simple lim_rlimit(), lim_max(), and lim_cur() API that return
  either an rlimit, or the current or max individual limit of the specified
  resource from a process.
- dosetrlimit() was renamed to kern_setrlimit() to match existing style of
  other similar syscall helper functions.
- The alpha OSF/1 compat layer no longer calls getrlimit() and setrlimit()
  (it didn't used the stackgap when it should have) but uses lim_rlimit()
  and kern_setrlimit() instead.
- The svr4 compat no longer uses the stackgap for resource limits calls,
  but uses lim_rlimit() and kern_setrlimit() instead.
- The ibcs2 compat no longer uses the stackgap for resource limits.  It
  also no longer uses the stackgap for accessing sysctl's for the
  ibcs2_sysconf() syscall but uses kernel_sysctl() instead.  As a result,
  ibcs2_sysconf() no longer needs Giant.
- The p_rlimit macro no longer exists.

Submitted by:	mtm (mostly, I only did a few cleanups and catchups)
Tested on:	i386
Compiled on:	alpha, amd64
2004-02-04 21:52:57 +00:00
Bruce Evans
9a44a82b61 Fixed breakage of scheduling in rev.1.29 of subr_4bsd.c. The
"scheduler" here has very little to do with scheduling.  It is actually
the swapper, and it really must be the last SYSINIT'ed item like its
comment says, since proc0 metamorphoses into swapper by calling
scheduler() last in mi_start(), and scheduler() never returns..  Rev.1.29
of subr_4bsd.c broke this by adding another SI_ORDER_FIRST item
(kproc_start() for schedcpu_thread() onto the SI_SUB_RUN_SCHEDULER_LIST.
The sorting of SYSINITs with identical orders (at all levels) is
apparently nondeterministic, so this resulted in schedule() sometimes
being called second last and schedcpu_thread() not being called at all.

This quick fix just changes the code to almost match the comment
(SI_ORDER_FIRST -> SI_ORDER_ANY).  "LAST" is misspelled "ANY", and
there is no way to ensure that there is only 1 very lst SYSINIT.
A more complete fix would remove the SYSINIT obfuscation.
2004-01-29 12:35:11 +00:00
Alan Cox
d88346020b - The Open Group Base Specifications Issue 6 specifies that an munmap(2)
must return EINVAL if size is zero.  Submitted by: tegge
 - In order to avoid a race condition in multithreaded applications, the
   check and removal operations by munmap(2) must be in the same critical
   section.  To accomodate this, vm_map_check_protection() is modified to
   require its caller to obtain at least a read lock on the map.
2003-11-10 01:37:40 +00:00
Bruce M Simpson
5d264f84f3 Revert previous commit. Come back vslock(), all is forgiven.
Pointy hat to:	bms
2003-10-05 12:41:08 +00:00
Bruce M Simpson
aac7652ecd Retire vslock() and vsunlock() with extreme prejudice.
Discussed with:	pete
2003-10-05 09:47:54 +00:00
Alan Cox
ef13663bb6 Three unrelated changes to vm_proc_new(): (1) add vm object locking on the
U pages object; (2) reorganize such that the U pages object is created and
filled in one block; and (3) remove an unnecessary clearing of PG_ZERO.
2003-08-18 01:31:43 +00:00
Marcel Moolenaar
710338e94f In vm_thread_swap{in|out}(), remove the alpha specific conditional
compilation and replace it with a call to cpu_thread_swap{in|out}().
This allows us to add similar code on ia64 without cluttering the
code even more.
2003-08-16 23:15:15 +00:00
Bruce M Simpson
abd498aa71 Add the mlockall() and munlockall() system calls.
- All those diffs to syscalls.master for each architecture *are*
   necessary. This needed clarification; the stub code generation for
   mlockall() was disabled, which would prevent applications from
   linking to this API (suggested by mux)
 - Giant has been quoshed. It is no longer held by the code, as
   the required locking has been pushed down within vm_map.c.
 - Callers must specify VM_MAP_WIRE_HOLESOK or VM_MAP_WIRE_NOHOLES
   to express their intention explicitly.
 - Inspected at the vmstat, top and vm pager sysctl stats level.
   Paging-in activity is occurring correctly, using a test harness.
 - The RES size for a process may appear to be greater than its SIZE.
   This is believed to be due to mappings of the same shared library
   page being wired twice. Further exploration is needed.
 - Believed to back out of allocations and locks correctly
   (tested with WITNESS, MUTEX_PROFILING, INVARIANTS and DIAGNOSTIC).

PR:             kern/43426, standards/54223
Reviewed by:    jake, alc
Approved by:    jake (mentor)
MFC after:	2 weeks
2003-08-11 07:14:08 +00:00
Poul-Henning Kamp
8f60c087e6 Change the layout policy of the swap_pager from a hardcoded width
striping to a per device round-robin algorithm.

Because of the policy of not attempting to retain previous swap
allocation on page-out, this means that a newly added swap device
almost instantly takes its 1/N share of the I/O load but it takes
somewhat longer for it to assume it's 1/N share of the pages if there
is plenty of space on the other devices.

Change the 8G total swapspace limitation to 8G per device instead
by using a per device blist rather than one global blist.  This
reduces the memory footprint by 75% (typically a couple hundred
kilobytes) for the common case with one swapdevice but NSWAPDEV=4.

Remove the compile time constant limit of number of swap devices,
there is no limit now.  Instead of a fixed size array, store the
per swapdev structure in a TAILQ.

Total swap space is still addressed by a 32 bit page number and
therefore the upper limit is now 2^42 bytes = 16TB (for i386).

We still do not allocate the first page of each device in order to
give some amount of protection to any bsdlabel at the start of the
device.

A new device is appended after the existing devices in the swap space,
no attempt is made to fill in holes left behind by swapoff (this can
trivially be changed should it ever become a problem).

The sysctl vm.nswapdev now reflects the number of currently configured
swap devices.

Rename vm_swap_size to swap_pager_avail for consistency with other
exported names.

Change argument type for vm_proc_swapin_all() and swap_pager_isswapped()
to be a struct swdevt pointer rather than an index.

Not changed: we are still using blists to manage the free space,
but since the swapspace is no longer fragmented by the striping
different resource managers might fare better.
2003-08-03 13:35:31 +00:00
Peter Wemm
15a7ad60fb Add #include "opt_kstack_pages.h" and "opt_kstack_max_pages.h" to remain
in sync with the backend machdep code.  When cpu_thread_init() does not
have the same idea of KSTACK_PAGES as the thing that created the kstack,
all hell breaks loose.

Bad alc! no cookie! :-)
2003-07-31 01:25:05 +00:00
Alan Cox
a04a7f2242 Use #ifdef __alpha__, not __alpha. 2003-06-15 00:12:42 +00:00
Alan Cox
49a2507bd1 Migrate the thread stack management functions from the machine-dependent
to the machine-independent parts of the VM.  At the same time, this
introduces vm object locking for the non-i386 platforms.

Two details:

1. KSTACK_GUARD has been removed in favor of KSTACK_GUARD_PAGES.  The
different machine-dependent implementations used various combinations
of KSTACK_GUARD and KSTACK_GUARD_PAGES.  To disable guard page, set
KSTACK_GUARD_PAGES to 0.

2. Remove the (unnecessary) clearing of PG_ZERO in vm_thread_new.  In
5.x, (but not 4.x,) PG_ZERO can only be set if VM_ALLOC_ZERO is passed
to vm_page_alloc() or vm_page_grab().
2003-06-14 23:23:55 +00:00
Alan Cox
89f4fca265 Move the *_new_altkstack() and *_dispose_altkstack() functions out of the
various pmap implementations into the machine-independent vm.  They were
all identical.
2003-06-14 06:20:25 +00:00
Alan Cox
8630c1173e Add vm object locking to various pagers' "get pages" methods, i386 stack
management functions, and a u area management function.
2003-06-13 03:02:28 +00:00
David E. O'Brien
874651b13c Use __FBSDID(). 2003-06-11 23:50:51 +00:00
Peter Wemm
77e2a274d0 GC unused cpu_wait() function 2003-06-11 05:20:33 +00:00
Poul-Henning Kamp
0b074f6c93 Remove unused variables
Found by:       FlexeLint
2003-05-31 19:51:05 +00:00
John Baldwin
90af4afacb - Merge struct procsig with struct sigacts.
- Move struct sigacts out of the u-area and malloc() it using the
  M_SUBPROC malloc bucket.
- Add a small sigacts_*() API for managing sigacts structures: sigacts_alloc(),
  sigacts_free(), sigacts_copy(), sigacts_share(), and sigacts_shared().
- Remove the p_sigignore, p_sigacts, and p_sigcatch macros.
- Add a mutex to struct sigacts that protects all the members of the struct.
- Add sigacts locking.
- Remove Giant from nosys(), kill(), killpg(), and kern_sigaction() now
  that sigacts is locked.
- Several in-kernel functions such as psignal(), tdsignal(), trapsignal(),
  and thread_stopped() are now MP safe.

Reviewed by:	arch@
Approved by:	re (rwatson)
2003-05-13 20:36:02 +00:00
Alexander Kabaev
104a9b7e3e Deprecate machine/limits.h in favor of new sys/limits.h.
Change all in-tree consumers to include <sys/limits.h>

Discussed on:	standards@
Partially submitted by: Craig Rodrigues <rodrigc@attbi.com>
2003-04-29 13:36:06 +00:00
Alan Cox
17cd3642fe - Lock the vm_object when performing swap_pager_isswapped().
- Assert that the vm_object is locked in swap_pager_isswapped().
2003-04-28 17:13:53 +00:00
John Baldwin
8f88740381 - Don't bother using the proc lock to test just P_SYSTEM as that is set in
fork1() and never changes.
- The proc lock is enough to cover reading p_state, so push down sched_lock
  into the PRS_NORMAL case of the switch on p_state.
2003-04-25 20:06:30 +00:00
Alan Cox
6a07e90d63 - Lock the vm_object when iterating over its list of resident pages. 2003-04-25 16:30:02 +00:00
John Baldwin
11edc1e0d7 Fix compiling in the NO_SWAPPING case.
Submitted by:	bde (partially)
2003-04-23 18:21:41 +00:00
John Baldwin
664f718ba1 - Always call faultin() in _PHOLD() if PS_INMEM is clear. This closes a
race where a thread could assume that a process was swapped in by
  PHOLD() when it actually wasn't fully swapped in yet.
- In faultin(), always msleep() if PS_SWAPPINGIN is set instead of doing
  this check after bumping p_lock in the PS_INMEM == 0 case.  Also,
  sched_lock is only needed for setting and clearning swapping PS_*
  flags and the swap thread inhibitor.
- Don't set and clear the thread swap inhibitor in the same loops as the
  pmap_swapin/out_thread() since we have to do it under sched_lock.
  Instead, mimic the treatment of the PS_INMEM flag and use separate loops
  to set the inhibitors when clearing PS_INMEM and clear the inhibitors
  when setting PS_INMEM.
- swapout() now returns with the proc lock held as it holds the lock
  while adjusting the swapping-related PS_* flags so that the proc lock
  can be used to test those flags.
- Only use the proc lock to check the swapping-related PS_* flags in
  several places.
- faultin() no longer requires sched_lock to be held by callers.
- Rename PS_SWAPPING to PS_SWAPPINGOUT to be less ambiguous now that we
  have PS_SWAPPINGIN.
2003-04-22 20:00:26 +00:00
Tom Rhodes
9faaf3b3c8 Add some tunable descriptions.
Submitted by:	hmp
Discussed with:	bde
2003-04-17 15:44:22 +00:00
Tom Rhodes
2a3eeaa240 Pre-content whitespace commit.
Discussed with:	bde
2003-04-17 15:39:12 +00:00
Alfred Perlstein
c3dfdfd132 use 'void *' instead of 'caddr_t' for useracc, kernacc, vslock and vsunlock. 2003-01-21 11:34:57 +00:00
Matthew Dillon
2d5c7e4506 Close the remaining user address mapping races for physical
I/O, CAM, and AIO.  Still TODO: streamline useracc() checks.

Reviewed by:	alc, tegge
MFC after:	7 days
2003-01-20 17:46:48 +00:00
Alan Cox
dc907f6632 - Hold the page queues lock around vm_page_wakeup(). 2002-12-24 04:24:58 +00:00