device have reference count problems. We mark the underlying object
ono-persistent, and account for the reference count that the VM system
maintainsfor the special device close. This should fix the removable
device problem.
files are off the vendor branch, so this should not change anything.
A "U" marker generally means that the file was not changed in between
the 4.4Lite and Lite-2 releases, and does not need a merge. "C" generally
means that there was a change.
[note, new file: cd9660_mount.h]
This is a really ugly bandaid on the problem, but it works well enough for
'ps -u' to start working again. The problem was caused by the user
address space shrinking by a little bit and the UPAGES being "cast off" to
become a seperate entity rather than being at the top of the process's
vmspace. That optimization was part of John's most recent VM speedups.
Now, rather than decoding the VM space, it merely ensures the pages are
in core and accesses them the same way the ptrace(PT_READ_U..) code does,
ie: off the p->p_addr pointer.
Implement a "variable" directory structure. Files that do not make
sense for the given process do not "appear" and cannot be opened.
For example, "system" processes do not have "file", "regs" or "fpregs",
because they do not have a user area.
"attempt" to fill in the user area of a given process when it is being
accessed via /proc/pid/mem (the user struct is just after
VM_MAXUSER_ADDRESS in the process address space.)
Dont do IO to the U area while it's swapped, hold it in place if possible.
Lock off access to the "ctl" file if it's done a setuid like the other
pseudo-files in there.
Speed up for vfs_bio -- addition of a routine bqrelse to greatly diminish
overhead for merged cache.
Efficiency improvement for vfs_cluster. It used to do alot of redundant
calls to cluster_rbuild.
Correct the ordering for vrele of .text and release of credentials.
Use the selective tlb update for 486/586/P6.
Numerous fixes to the size of objects allocated for files. Additionally,
fixes in the various pagers.
Fixes for proper positioning of vnode_pager_setsize in msdosfs and ext2fs.
Fixes in the swap pager for exhausted resources. The pageout code
will not as readily thrash.
Change the page queue flags (PG_ACTIVE, PG_INACTIVE, PG_FREE, PG_CACHE) into
page queue indices (PQ_ACTIVE, PQ_INACTIVE, PQ_FREE, PQ_CACHE),
thereby improving efficiency of several routines.
Eliminate even more unnecessary vm_page_protect operations.
Significantly speed up process forks.
Make vm_object_page_clean more efficient, thereby eliminating the pause
that happens every 30seconds.
Make sequential clustered writes B_ASYNC instead of B_DELWRI even in the
case of filesystems mounted async.
Fix a panic with busy pages when write clustering is done for non-VMIO
buffers.
seems to work hre just fine though I can't check every file
that changed due to limmited h/w, however I've checked enught to be petty
happy withe hte code..
WARNING... struct lkm[mumble] has changed
so it might be an idea to recompile any lkm related programs
most devsw referenced functions are now static, as they are
in the same file as their devsw structure. I've also added DEVFS
support for nearly every device in the system, however
many of the devices have 'incorrect' names under DEVFS
because I couldn't quickly work out the correct naming conventions.
(but devfs won't be coming on line for a month or so anyhow so that doesn't
matter)
If you "OWN" a device which would normally have an entry in /dev
then search for the devfs_add_devsw() entries and munge to make them right..
check out similar devices to see what I might have done in them in you
can't see what's going on..
for a laugh compare conf.c conf.h defore and after... :)
I have not doen DEVFS entries for any DISKSLICE devices yet as that will be
a much more complicated job.. (pass 5 :)
pass 4 will be to make the devsw tables of type (cdevsw * )
rather than (cdevsw)
seems to work here..
complaints to the usual places.. :)
cd9660_rrip.c:
Added lots of bogus casts to hide type errors exposed by the prototypes.
(Different structs are assumed to have a common prefix.)
cd9660_vnops.c:
Finished staticizing.
add a few safety checks in specfs because
now it's possible to get entries in [cd]devsw[] which are ALL NULL
so it's better to discover this BEFORE jumping into the d_open() entry..
more check to come later.. this getsthe code to the stage where I
can start testing it, even if I haven't caught every little error case...
I guess I'll find them quick enough..
for certain common combinations of directory sizes, cluster sizes, and i/o
sizes (e.g., 4K, 4K, and 4K). The fix in rev. 1.21 was incomplete.
Reviewed by: dfr
Obtained from: party from NetBSD
The fix for this in Lite-2 is more complete, but these quick hacks of mine
are safer for now. I plan to integrate the additional Lite-2 stuff at some
later time. Should completely fix PR810.
it 1138 times (:-() in casts and a few more times in declarations.
This change is null for the i386.
The type has to be `typedef int vop_t(void *)' and not `typedef
int vop_t()' because `gcc -Wstrict-prototypes' warns about the
latter. Since vnode op functions are called with args of different
(struct pointer) types, neither of these function types is any use
for type checking of the arg, so it would be preferable not to use
the complete function type, especially since using the complete
type requires adding 1138 casts to avoid compiler warnings and
another 40+ casts to reverse the function pointer conversions before
calling the functions.
Should anybody out there wonder about this vendetta against global
variables, it is basically to make it more visible what our interfaces
in the kernel really are.
I'm almost convinced we should have a
#define PUBLIC /* public interface */
and use it in the #includes...
filesystem layer, as was done in lite-2. Merged in some other cosmetic
changes while I was at it. Rewrote most of msdosfs_access() to be more
like ufs_access() and to include the FS read-only check.
Obtained from: partially from 4.4BSD-lite2
calls.
Found by: gcc -Wstrict-prototypes after I supplied some of the 5000+
missing prototypes. Now I have 9000+ lines of warnings and errors
about bogus conversions of function pointers.
SunOS and SCO. You can then even use the pipe as a cheap fifo stack
(yuck!). A semantic change also important (but not limited) to iBCS2
compatibility.
Submitted by: swallace
wrong vp's ops vector being used by changing the VOP_LINK's argument order.
The special-case hack doesn't go far enough and breaks the generic
bypass routine used in some non-leaf filesystems. Pointed out by Kirk
McKusick.
don't go away when the kernel is compiled with -O.
The functions are backed up by extern versions in cd9660_util.c,
but these versions are disabled by `#ifdef __notanymore__'. They
could have been enabled by using `#if defined(__notanymore__) ||
!defined(__OPTIMIZE__)' but then I would have had to check that
they still work. The correct way to handle all this is to replace
`extern inline' by `EXTERN_INLINE' and define `EXTERN_INLINE' as
`extern inline' in most modules and as empty in one module.
associated files.
Submitted by: leo@dachau.marco.de (Matthias Pfaller)
Not-obtained from: NetBSD. Instead sent directly to me by Matthias.
(Sorry, this is to prevent people from claiming i might have gotten
this from NetBSD. :)
proc or any VM system structure will have to be rebuilt!!!
Much needed overhaul of the VM system. Included in this first round of
changes:
1) Improved pager interfaces: init, alloc, dealloc, getpages, putpages,
haspage, and sync operations are supported. The haspage interface now
provides information about clusterability. All pager routines now take
struct vm_object's instead of "pagers".
2) Improved data structures. In the previous paradigm, there is constant
confusion caused by pagers being both a data structure ("allocate a
pager") and a collection of routines. The idea of a pager structure has
escentially been eliminated. Objects now have types, and this type is
used to index the appropriate pager. In most cases, items in the pager
structure were duplicated in the object data structure and thus were
unnecessary. In the few cases that remained, a un_pager structure union
was created in the object to contain these items.
3) Because of the cleanup of #1 & #2, a lot of unnecessary layering can now
be removed. For instance, vm_object_enter(), vm_object_lookup(),
vm_object_remove(), and the associated object hash list were some of the
things that were removed.
4) simple_lock's removed. Discussion with several people reveals that the
SMP locking primitives used in the VM system aren't likely the mechanism
that we'll be adopting. Even if it were, the locking that was in the code
was very inadequate and would have to be mostly re-done anyway. The
locking in a uni-processor kernel was a no-op but went a long way toward
making the code difficult to read and debug.
5) Places that attempted to kludge-up the fact that we don't have kernel
thread support have been fixed to reflect the reality that we are really
dealing with processes, not threads. The VM system didn't have complete
thread support, so the comments and mis-named routines were just wrong.
We now use tsleep and wakeup directly in the lock routines, for instance.
6) Where appropriate, the pagers have been improved, especially in the
pager_alloc routines. Most of the pager_allocs have been rewritten and
are now faster and easier to maintain.
7) The pagedaemon pageout clustering algorithm has been rewritten and
now tries harder to output an even number of pages before and after
the requested page. This is sort of the reverse of the ideal pagein
algorithm and should provide better overall performance.
8) Unnecessary (incorrect) casts to caddr_t in calls to tsleep & wakeup
have been removed. Some other unnecessary casts have also been removed.
9) Some almost useless debugging code removed.
10) Terminology of shadow objects vs. backing objects straightened out.
The fact that the vm_object data structure escentially had this
backwards really confused things. The use of "shadow" and "backing
object" throughout the code is now internally consistent and correct
in the Mach terminology.
11) Several minor bug fixes, including one in the vm daemon that caused
0 RSS objects to not get purged as intended.
12) A "default pager" has now been created which cleans up the transition
of objects to the "swap" type. The previous checks throughout the code
for swp->pg_data != NULL were really ugly. This change also provides
the rudiments for future backing of "anonymous" memory by something
other than the swap pager (via the vnode pager, for example), and it
allows the decision about which of these pagers to use to be made
dynamically (although will need some additional decision code to do
this, of course).
13) (dyson) MAP_COPY has been deprecated and the corresponding "copy
object" code has been removed. MAP_COPY was undocumented and non-
standard. It was furthermore broken in several ways which caused its
behavior to degrade to MAP_PRIVATE. Binaries that use MAP_COPY will
continue to work correctly, but via the slightly different semantics
of MAP_PRIVATE.
14) (dyson) Sharing maps have been removed. It's marginal usefulness in a
threads design can be worked around in other ways. Both #12 and #13
were done to simplify the code and improve readability and maintain-
ability. (As were most all of these changes)
TODO:
1) Rewrite most of the vnode pager to use VOP_GETPAGES/PUTPAGES. Doing
this will reduce the vnode pager to a mere fraction of its current size.
2) Rewrite vm_fault and the swap/vnode pagers to use the clustering
information provided by the new haspage pager interface. This will
substantially reduce the overhead by eliminating a large number of
VOP_BMAP() calls. The VOP_BMAP() filesystem interface should be
improved to provide both a "behind" and "ahead" indication of
contiguousness.
3) Implement the extended features of pager_haspage in swap_pager_haspage().
It currently just says 0 pages ahead/behind.
4) Re-implement the swap device (swstrategy) in a more elegant way, perhaps
via a much more general mechanism that could also be used for disk
striping of regular filesystems.
5) Do something to improve the architecture of vm_object_collapse(). The
fact that it makes calls into the swap pager and knows too much about
how the swap pager operates really bothers me. It also doesn't allow
for collapsing of non-swap pager objects ("unnamed" objects backed by
other pagers).
regular user could panic the machine with a simple "tail /proc/curproc/mem"
command. The problem was twofold: both kernfs and procfs didn't fill in
the mnt_stat statfs struct (which would later lead to an integer divide
fault in the vnode pager), and kernfs bogusly paniced if a bmap was
attempted.
Reviewed by: John Dyson
These changes solve the problem in a general way by moving the
initialization out of the individual fs_mountroot's and into swaponvp().
Submitted by: Poul-Henning Kamp
msdosfs_lookup() did no validation to see if the caller was validated
to delete/rename/create files. msdosfs_setattr() did no validation
to see if the caller was allowed to change the file permissions (turn
on/off the write bit) or update the file modification time (utimes).
The routines were fixed to validate the calls just like ufs does.
Fix PR 303: msdosfs: moving a file into another directory causes panic.
" ... the code that does the rename already has the denode
locked when msdosfs_hashins() gets called, resulting in the panic
when the routine attempts to lock the denode again.
...
The attached patch changes the msdosfs_hashins() routine to not lock the
denode. The caller is now resposible for obtaining the lock instead
of having msdosfs_hashins() do it for them."
Fixed remaining known bugs in the buffer IO and VM system.
vfs_bio.c:
Fixed some race conditions and locking bugs. Improved performance
by removing some (now) unnecessary code and fixing some broken
logic.
Fixed process accounting of # of FS outputs.
Properly handle NFS interrupts (B_EINTR).
(various)
Replaced calls to clrbuf() with calls to an optimized routine
called vfs_bio_clrbuf().
(various FS sync)
Sync out modified vnode_pager backed pages.
ffs_vnops.c:
Do two passes: Sync out file data first, then indirect blocks.
vm_fault.c:
Fixed deadly embrace caused by acquiring locks in the wrong order.
vnode_pager.c:
Changed to use buffer I/O system for writing out modified pages. This
should fix the problem with the modification date previous not getting
updated. Also dramatically simplifies the code. Note that this is
going to change in the future and be implemented via VOP_PUTPAGES().
vm_object.c:
Fixed a pile of bugs related to cleaning (vnode) objects. The performance
of vm_object_page_clean() is terrible when dealing with huge objects,
but this will change when we implement a binary tree to keep the object
pages sorted.
vm_pageout.c:
Fixed broken clustering of pageouts. Fixed race conditions and other
lockup style bugs in the scanning of pages. Improved performance.
VFCF_NETWORK (this FS goes over the net)
VFCF_READONLY (read-write mounts do not make any sense)
VFCF_SYNTHETIC (data in this FS is not real)
VFCF_LOOPBACK (this FS aliases something else)
cd9660 is readonly; nullfs, umapfs, and union are loopback; NFS is netowkr;
procfs, kernfs, and fdesc are synthetic.
