Commit Graph

870 Commits

Author SHA1 Message Date
Paul Saab
9730a5daab Add MAP_NOCORE to mmap(2), and MADV_NOCORE and MADV_CORE to madvise(2).
This
This feature allows you to specify if mmap'd data is included in
an application's corefile.

Change the type of eflags in struct vm_map_entry from u_char to
vm_eflags_t (an unsigned int).

Reviewed by:	dillon,jdp,alfred
Approved by:	jkh
2000-02-28 04:10:35 +00:00
Matthew Dillon
1f6889a1eb Fix null-pointer dereference crash when the system is intentionally
run out of KVM through a mmap()/fork() bomb that allocates hundreds
    of thousands of vm_map_entry structures.

    Add panic to make null-pointer dereference crash a little more verbose.

    Add a new sysctl, vm.max_proc_mmap, which specifies the maximum number
    of mmap()'d spaces (discrete vm_map_entry's in the process).  The value
    defaults to around 9000 for a 128MB machine.  The test is scaled for the
    number of processes sharing a vmspace (aka linux threads).  Setting
    the value to 0 disables the feature.

PR: kern/16573
Approved by: jkh
2000-02-16 21:11:33 +00:00
Matthew Dillon
6e8b65472e The swapdev_vp changes made to rip out the swap specfs interaction
also broke diskless swapping.  Moving the swapdev_vp initialization
    to more commonly run code solves the problem.

PR: kern/16165
Additional testing by: David Gilbert <dgilbert@velocet.ca>
2000-01-25 17:49:12 +00:00
Matthew Dillon
ff359f84c9 Fix a deadlock between msync(..., MS_INVALIDATE) and vm_fault. The
invalidation code cannot wait for paging to complete while holding a
    vnode lock, so we don't wait.  Instead we simply allow the lower level
    code to simply block on any busy pages it encounters.  I think Yahoo
    may be the only entity in the entire world that actually uses this
    msync feature :-).

Bug reported by:  Paul Saab <paul@mu.org>
2000-01-21 20:17:01 +00:00
Poul-Henning Kamp
ba4ad1fcea Give vn_isdisk() a second argument where it can return a suitable errno.
Suggested by:	bde
2000-01-10 12:04:27 +00:00
Guido van Rooij
00d76afede Use MAP_NOSYNC for vnodes without any links in their filesystem.
This is necessary for vmware: it does not use an anonymous mmap for
the memory of the virtual system. In stead it creates a temp file an
unlinks it. For a 50 MB file, this results in a ot of syncing
every 30 seconds.

Reviewed by:	Matthew Dillon <dillon@backplane.com>
2000-01-03 19:13:53 +00:00
Peter Wemm
c447342094 Change #ifdef KERNEL to #ifdef _KERNEL in the public headers. "KERNEL"
is an application space macro and the applications are supposed to be free
to use it as they please (but cannot).  This is consistant with the other
BSD's who made this change quite some time ago.  More commits to come.
1999-12-29 05:07:58 +00:00
Peter Wemm
ea3aecf5b4 Fix the swap backed vn case - this was broken by my rev 1.128 to
swap_pager.c and related commits.

Essentially swap_pager.c is backed out to before the changes, but
swapdev_vp is converted into a real vnode with just VOP_STRATEGY().
It no longer abuses specfs vnops and no longer needs a dev_t and
/dev/drum (or /dev/swapdev) for the intermediate layer.

This essentially restores the vnode interface as the interface to the
bottom of the swap pager, and vm_swap.c provides a clean vnode interface.

This will need to be revisited when we swap to files (vnodes) - which
is the other reason for keeping the vnode interface between the swap pager
and the swap devices.

OK'ed by:	dillon
1999-12-28 07:30:55 +00:00
Eivind Eklund
762e6b856c Introduce NDFREE (and remove VOP_ABORTOP) 1999-12-15 23:02:35 +00:00
Matthew Dillon
4f79d873c1 Add MAP_NOSYNC feature to mmap(), and MADV_NOSYNC and MADV_AUTOSYNC to
madvise().

    This feature prevents the update daemon from gratuitously flushing
    dirty pages associated with a mapped file-backed region of memory.  The
    system pager will still page the memory as necessary and the VM system
    will still be fully coherent with the filesystem.  Modifications made
    by other means to the same area of memory, for example by write(), are
    unaffected.  The feature works on a page-granularity basis.

    MAP_NOSYNC allows one to use mmap() to share memory between processes
    without incuring any significant filesystem overhead, putting it in
    the same performance category as SysV Shared memory and anonymous memory.

Reviewed by: julian, alc, dg
1999-12-12 03:19:33 +00:00
Eivind Eklund
6bdfe06ad9 Lock reporting and assertion changes.
* lockstatus() and VOP_ISLOCKED() gets a new process argument and a new
  return value: LK_EXCLOTHER, when the lock is held exclusively by another
  process.
* The ASSERT_VOP_(UN)LOCKED family is extended to use what this gives them
* Extend the vnode_if.src format to allow more exact specification than
  locked/unlocked.

This commit should not do any semantic changes unless you are using
DEBUG_VFS_LOCKS.

Discussed with:	grog, mch, peter, phk
Reviewed by:	peter
1999-12-11 16:13:02 +00:00
Luoqi Chen
91c28bfde0 User ldt sharing. 1999-12-06 04:53:08 +00:00
Poul-Henning Kamp
c464420c89 Report swapdevices as cdevs rather than bdevs.
Remove unused dev2budev() function.
1999-11-29 21:37:18 +00:00
Alan Cox
2b71c841f5 Remove nonsensical vm_map_{clear,set}_recursive() calls
from vm_map_pageable().  At the point they called, vm_map_pageable()
holds a read (or shared) lock on the map.  The purpose
of vm_map_{clear,set}_recursive() is to disable/enable repeated
write (or exclusive) lock requests by the same process.
1999-11-25 20:21:52 +00:00
Alan Cox
2ed14a92db Correct the following error: vm_map_pageable() on a COW'ed (post-fork)
vm_map always failed because vm_map_lookup() looked at
 "vm_map_entry->wired_count" instead of "(vm_map_entry->eflags &
 MAP_ENTRY_USER_WIRED)".  The effect was that many page
 wiring operations by sysctl were (silently) failing.
1999-11-23 06:51:28 +00:00
Poul-Henning Kamp
24e7ab7c0b Isolate the swapdev_vp "not quite" vnode in the only source file which
needs it now that /dev/drum is gone.

Reviewed by: eivind, peter
1999-11-22 15:27:09 +00:00
Peter Wemm
cdacc6ab42 Remove the non-functional "swap device" userland front-end to the
multiplexed underlying swap devices (/dev/drum).  The only thing it did
was to allow root to open /dev/drum, but not do anything with it.
Various utilities used to grovel around in here, but Matt has written
a much nicer (and clean) front-end to this for libkvm, and nothing uses
the old system any more.

The VM system was calling VOP_STRATEGY() on the vp of the first underlying
swap device (not the /dev/drum one, the first real device), and using
the VOP system to indirectly (and only) call swstrategy() to choose
an underlying device and enqueue it on that device.  I have changed it
to avoid diverting through the VOP system and to call the only possible
target directly, saving a little bit of time and some complexity.

In all, nothing much changes, except some scaffolding to support the
roundabout way of calling swstrategy() is gone.

Matt gave me the ok to do this some time ago, and I apologize for taking
so long to get around to it.
1999-11-18 06:55:40 +00:00
Alan Cox
e6ce529511 Two changes: (1) Use vm_page_unqueue_nowakeup in vm_page_alloc
instead of duplicating the code.  (2) If a wired page is passed
to vm_page_free_toq, panic instead of printing a friendly warning.
(If we don't panic here, we'll just panic later in vm_page_unwire
obscuring the problem.)
1999-11-10 05:23:19 +00:00
Alan Cox
98b5130932 Remove unused declarations. 1999-11-08 00:53:34 +00:00
Alan Cox
79e1e3b9b4 Remove unused #include's.
Submitted by:	phk
1999-11-07 20:03:54 +00:00
Alan Cox
1ab41ed97c The functions declared by this header file no longer exist.
Submitted by:	phk (in part)
1999-11-07 06:46:48 +00:00
Alan Cox
12a69a6af4 Reverse the sense of the test in the KASSERT's from the last commit. 1999-10-30 09:09:02 +00:00
Alan Cox
be72f78813 The core of this patch is to vm/vm_page.h. The effects are two-fold: (1) to
eliminate an extra (useless) level of indirection in half of the page
queue accesses and (2) to use a single name for each queue throughout,
instead of, e.g., "vm_page_queue_active" in some places and
"vm_page_queues[PQ_ACTIVE]" in others.

Reviewed by:	dillon
1999-10-30 07:37:14 +00:00
Poul-Henning Kamp
02c58685a4 Change useracc() and kernacc() to use VM_PROT_{READ|WRITE|EXECUTE} for the
"rw" argument, rather than hijacking B_{READ|WRITE}.

Fix two bugs (physio & cam) resulting by the confusion caused by this.

Submitted by:   Tor.Egge@fast.no
Reviewed by:    alc, ken (partly)
1999-10-30 06:32:05 +00:00
Poul-Henning Kamp
923502ff91 useracc() the prequel:
Merge the contents (less some trivial bordering the silly comments)
of <vm/vm_prot.h> and <vm/vm_inherit.h> into <vm/vm.h>.  This puts
the #defines for the vm_inherit_t and vm_prot_t types next to their
typedefs.

This paves the road for the commit to follow shortly: change
useracc() to use VM_PROT_{READ|WRITE} rather than B_{READ|WRITE}
as argument.
1999-10-29 18:09:36 +00:00
Alan Cox
02577fa23e Remove the last vestiges of "vm_map_t phys_map". It's been unused
since i386/i386/machdep.c rev 1.45 (or 1994 :-) ).
1999-10-29 05:17:20 +00:00
Alan Cox
6877f580de Shrink "struct vm_object" by not spending a full 32 bits
on "objtype_t".
1999-10-27 17:47:24 +00:00
Poul-Henning Kamp
6ee0a468fe Fix a panic(8) implementation:
hexdump -C < /dev/drum
by simply refusing to do I/O from userland.
a panic.  I'm not sure we even need /dev/drum anymore, it seems
to have been broken for a long time thi
1999-10-08 19:10:18 +00:00
Poul-Henning Kamp
9753e1c4c4 Introduce swopen to prevent blockdevice opens and insist on minor==0. 1999-10-04 13:09:30 +00:00
Poul-Henning Kamp
03bf3ccb9c Give the swap device a D_DISK flag against my better judgement.
TODO: add an open routing which fails for bdev opens.
1999-10-04 12:27:58 +00:00
Dmitrij Tejblum
62dc52f5dd Plug an accounting leak: count pages in ZONE_INTERRUPT zones as wired. 1999-09-30 07:35:50 +00:00
Poul-Henning Kamp
d6a0e38a1b Remove five now unused fields from struct cdevsw. They should never
have been there in the first place.  A GENERIC kernel shrinks almost 1k.

Add a slightly different safetybelt under nostop for tty drivers.

Add some missing FreeBSD tags
1999-09-25 18:24:47 +00:00
Matthew Dillon
b430905573 cleanup madvise code, add a few more sanity checks.
Reviewed by:	Alan Cox <alc@cs.rice.edu>,  dg@root.com
1999-09-21 05:00:48 +00:00
Matthew Dillon
40360b1bbb Final commit to remove vnode->v_lastr. vm_fault now handles read
clustering issues (replacing code that used to be in
    ufs/ufs/ufs_readwrite.c).  vm_fault also now uses the new VM page counter
    inlines.

    This completes the changeover from vnode->v_lastr to vm_entry_t->v_lastr
    for VM, and fp->f_nextread and fp->f_seqcount (which have been in the
    tree for a while).  Determination of the I/O strategy (sequential, random,
    and so forth) is now handled on a descriptor-by-descriptor basis for
    base I/O calls, and on a memory-region-by-memory-region and
    process-by-process basis for VM faults.

Reviewed by:	David Greenman <dg@root.com>, Alan Cox <alc@cs.rice.edu>
1999-09-21 00:36:16 +00:00
Matthew Dillon
4cc712004c Fix bug in pipe code relating to writes of mmap'd but illegal address
spaces which cross a segment boundry in the page table.  pmap_kextract()
    is not designed for access to the user space portion of the page
    table and cannot handle the null-page-directory-entry case.

    The fix is to have vm_fault_quick() return a success or failure which
    is then used to avoid calling pmap_kextract().
1999-09-20 19:08:48 +00:00
Matthew Dillon
479112dfd9 Remove inappropriate VOP_FSYNC from vm_object_page_clean(). The fsync
syncs the entire underlying file rather then just the requested range,
    resulting in huge inefficiencies when the VM system is articulated in
    a certain way.  The VOP_FSYNC was also found to massively reduce NFS
    performance in certain cases.

    Change MADV_DONTNEED and MADV_FREE to call vm_page_dontneed() instead
    of vm_page_deactivate().  Using vm_page_deactivate() causes all
    inactive and cache pages to be recycled before the dontneed/free page
    is recycled, effectively flushing our entire VM inactive & cache
    queues continuously even if only a few pages are being actively MADV
    free'd and reused (such as occurs with a sequential scan of a
    memory-mapped file).

Reviewed by:	Alan Cox <alc@cs.rice.edu>, David Greenman <dg@root.com>
1999-09-17 05:48:36 +00:00
Matthew Dillon
3f873b513b Add 'lastr' field to vm_map_entry in preparation for its removal
from the vnode.  (The changeover is undergoing final testing and
    will be committed soon).

Reviewed by:	Alan Cox <alc@cs.rice.edu>, David Greenman <dg@root.com>
1999-09-17 05:40:17 +00:00
Matthew Dillon
24579ca1d7 The vnode pager (used when you do file-backed mmaps) must use the
underlying physical sector size when aligning I/O transfer sizes.
    It cannot assume 512 bytes.

    We assume the underlying sector size is a power of 2.  If it isn't,
    mmap() will break badly anyway (in the same way mmap broke with NFS
    when NFS tried to cache piecemeal write ranges in buffers, before
    we enforced read-buffer-before-write-piecemeal for NFS).

Reviewed by:	Alan Cox <alc@cs.rice.edu>, David Greenman <dg@root.com>
1999-09-17 05:17:59 +00:00
Matthew Dillon
4dcc5c2d1d Fix a number of spl bugs related to reserving and freeing swap space.
Swap space can be freed from an interrupt and so swap reservation and
    freeing must occur at splvm.

    Add swap_pager_reserve() code to support a new swap pre-reservation
    capability for the VN device.

    Generally cleanup the swap code by simplifying the swp_pager_meta_build()
    static function and consolidating the SWAPBLK_NONE test from a bit test
    to an absolute compare.  The bit test was left over from a rejected
    swap allocation scheme that was not ultimately committed.  A few other
    minor cleanups were also made.

    Reorganize the swap strategy code, again for VN support, to not
    reallocate swap when writing as this messes up pre-reservation and
    can fragment I/O unnecessarily as VN-baesd disk is messed around with.

Reviewed by:	Alan Cox <alc@cs.rice.edu>, David Greenman <dg@root.com>
1999-09-17 05:09:24 +00:00
Matthew Dillon
2eab8b3609 Add required BUF_KERNPROC to flushchainbuf() to disassociate the
current process from the exclusive lock prior to initiating I/O.

    This fixes a panic related to swap-backed VN disks

Reviewed by:	Alan Cox <alc@cs.rice.edu>, David Greenman <dg@root.com>
1999-09-17 05:03:27 +00:00
Matthew Dillon
90ecac61c0 Reviewed by: Alan Cox <alc@cs.rice.edu>, David Greenman <dg@root.com>
Replace various VM related page count calculations strewn over the
    VM code with inlines to aid in readability and to reduce fragility
    in the code where modules depend on the same test being performed
    to properly sleep and wakeup.

    Split out a portion of the page deactivation code into an inline
    in vm_page.c to support vm_page_dontneed().

    add vm_page_dontneed(), which handles the madvise MADV_DONTNEED
    feature in a related commit coming up for vm_map.c/vm_object.c.  This
    code prevents degenerate cases where an essentially active page may
    be rotated through a subset of the paging lists, resulting in premature
    disposal.
1999-09-17 04:56:40 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Poul-Henning Kamp
dbafb3660f Simplify the handling of VCHR and VBLK vnodes using the new dev_t:
Make the alias list a SLIST.

        Drop the "fast recycling" optimization of vnodes (including
        the returning of a prexisting but stale vnode from checkalias).
        It doesn't buy us anything now that we don't hardlimit
        vnodes anymore.

        Rename checkalias2() and checkalias() to addalias() and
        addaliasu() - which takes dev_t and udev_t arg respectively.

        Make the revoke syscalls use vcount() instead of VALIASED.

        Remove VALIASED flag, we don't need it now and it is faster
        to traverse the much shorter lists than to maintain the
        flag.

        vfs_mountedon() can check the dev_t directly, all the vnodes
        point to the same one.

Print the devicename in specfs/vprint().

Remove a couple of stale LFS vnode flags.

Remove unimplemented/unused LK_DRAINED;
1999-08-26 14:53:31 +00:00
Brian Feldman
076dab2983 When the SYSINIT() was removed, it was replaced with a make_dev on-demand
creation of /dev/drum via calling swapon. However, the make_dev has a
bogus (insofar that it hasn't been added yet) cdevsw, so later we end
up crashing with a null pointer dereference on the swap vp's specinfo.
The specinfo points to a dev_t with a major of 254 (uninitialized), and
we get a crash on its d_strategy being called.

The simple solution to this is to call cdevsw_add before the make_dev
is ever used. This fixes the panic which occurred upon swapping.
1999-08-24 05:58:35 +00:00
Bruce Evans
af647dde33 Use devtoname to print dev_t's instead of casting them to u_long for
misprinting with %lx.

Cast pointers to intptr_t instead of casting them to long.  Cosmetic.
1999-08-23 23:55:03 +00:00
Poul-Henning Kamp
9dcbe2404a Convert DEVFS hooks in (most) drivers to make_dev().
Diskslice/label code not yet handled.

Vinum, i4b, alpha, pc98 not dealt with (left to respective Maintainers)

Add the correct hook for devfs to kern_conf.c

The net result of this excercise is that a lot less files depends on DEVFS,
and devtoname() gets more sensible output in many cases.

A few drivers had minor additional cleanups performed relating to cdevsw
registration.

A few drivers don't register a cdevsw{} anymore, but only use make_dev().
1999-08-23 20:59:21 +00:00
Alan Cox
e394748e8e Correct the inconsistent formatting in struct vm_map.
Addendum to rev 1.47: submitted by dillon.
1999-08-23 18:16:05 +00:00
Alan Cox
b7d742995e struct vm_map:
The lock structure cannot be the first element of the vm_map
	because this can result in livelock between two or more system
	processes trying to kmem_alloc_wait.
1999-08-23 18:08:34 +00:00
Alan Cox
aeea9b3695 Remove two unused variable declarations. 1999-08-22 00:01:46 +00:00
Alan Cox
14068cfed2 vm_page_alloc and contigmalloc1:
Verify that free pages are not dirty.

Submitted by:	dillon
1999-08-20 06:32:00 +00:00