- first program lock a region in a file,
- second program wait on the lock,
- first program extend the region,
- second program interrupted by a signal.
particularly annoying hack, namely having the linker bash the moduledata
to set the container pointer, preventing it being const. In the process,
a stack of warnings were fixed and will probably allow a revisit of the
const C_SYSINIT() changes. This explicitly registers modules in files or
preload areas with the module system first, and let them initialize via
SYSINIT/DECLARE_MODULE later in their SI_ORDER_xxx order. The kludge of
finding the containing file is no longer needed since the registration
of modules onto the modules list is done in the context of initializing
the linker file.
Made a new (inline) function devsw(dev_t dev) and substituted it.
Changed to the BDEV variant to this format as well: bdevsw(dev_t dev)
DEVFS will eventually benefit from this change too.
Virtualize bdevsw[] from cdevsw. bdevsw() is now an (inline)
function.
Join CDEV_MODULE and BDEV_MODULE to DEV_MODULE (please pay attention
to the order of the cmaj/bmaj arguments!)
Join CDEV_DRIVER_MODULE and BDEV_DRIVER_MODULE to DEV_DRIVER_MODULE
(ditto!)
(Next step will be to convert all bdev dev_t's to cdev dev_t's
before they get to do any damage^H^H^H^H^H^Hwork in the kernel.)
for elf kernels (it is broken for all kernels due to lack of egcs support).
Renaming of many assembler labels is avoided by declaring by declaring
the labels that need to be visible to gprof as having type "function"
and depending on the elf version of gprof being zealous about discarding
the others. A few type declarations are still missing, mainly for SMP.
PR: 9413
Submitted by: Assar Westerlund <assar@sics.se> (initial parts)
INIT_PATH config option.
Also fix two bugs which caused an infinite loop in none of the programs
in the init_path were found. That code was obviously not tested!
piecemeal, middle-of-file writes for NFS. These hacks have caused no
end of trouble, especially when combined with mmap(). I've removed
them. Instead, NFS will issue a read-before-write to fully
instantiate the struct buf containing the write. NFS does, however,
optimize piecemeal appends to files. For most common file operations,
you will not notice the difference. The sole remaining fragment in
the VFS/BIO system is b_dirtyoff/end, which NFS uses to avoid cache
coherency issues with read-merge-write style operations. NFS also
optimizes the write-covers-entire-buffer case by avoiding the
read-before-write. There is quite a bit of room for further
optimization in these areas.
The VM system marks pages fully-valid (AKA vm_page_t->valid =
VM_PAGE_BITS_ALL) in several places, most noteably in vm_fault. This
is not correct operation. The vm_pager_get_pages() code is now
responsible for marking VM pages all-valid. A number of VM helper
routines have been added to aid in zeroing-out the invalid portions of
a VM page prior to the page being marked all-valid. This operation is
necessary to properly support mmap(). The zeroing occurs most often
when dealing with file-EOF situations. Several bugs have been fixed
in the NFS subsystem, including bits handling file and directory EOF
situations and buf->b_flags consistancy issues relating to clearing
B_ERROR & B_INVAL, and handling B_DONE.
getblk() and allocbuf() have been rewritten. B_CACHE operation is now
formally defined in comments and more straightforward in
implementation. B_CACHE for VMIO buffers is based on the validity of
the backing store. B_CACHE for non-VMIO buffers is based simply on
whether the buffer is B_INVAL or not (B_CACHE set if B_INVAL clear,
and vise-versa). biodone() is now responsible for setting B_CACHE
when a successful read completes. B_CACHE is also set when a bdwrite()
is initiated and when a bwrite() is initiated. VFS VOP_BWRITE
routines (there are only two - nfs_bwrite() and bwrite()) are now
expected to set B_CACHE. This means that bowrite() and bawrite() also
set B_CACHE indirectly.
There are a number of places in the code which were previously using
buf->b_bufsize (which is DEV_BSIZE aligned) when they should have
been using buf->b_bcount. These have been fixed. getblk() now clears
B_DONE on return because the rest of the system is so bad about
dealing with B_DONE.
Major fixes to NFS/TCP have been made. A server-side bug could cause
requests to be lost by the server due to nfs_realign() overwriting
other rpc's in the same TCP mbuf chain. The server's kernel must be
recompiled to get the benefit of the fixes.
Submitted by: Matthew Dillon <dillon@apollo.backplane.com>
"use" and replaces it with equivalent inline code. The reason is that
Perl has some very nasty circular dependancies, and I am trying to
get the System Perl upgraded by one maintenance level.
The basic rule, until I can find a way to solve this, is that
the build tools MAY NOT use any library code; it must all be inline.
range attributes after they have been extracted from the master.
Hook up the i686 MP code to do this for each AP.
Be more careful about printing the default memory type for the i686.
Suggestions from: luoqi
This patch also moves the bogus comment (the comment is still not quite
right) and (as a side effect) removes some verbose initialisations (we
depend on static initialisation to 0 for almost everything in proc0).
The alpha kernels are bootable again. The change won't affect i386's
until machdep.c is changed.
Submitted by: bde
In heavy-writing situations, QUEUE_LRU can contain a large number
of DELWRI buffers at its head. These buffers must be moved
to the tail if they cannot be written async in order to reduce
the scanning time required to skip past these buffers in later
getnewbuf() calls.
Submitted by: Matthew Dillon <dillon@apollo.backplane.com>
This is a seriously beefed up chroot kind of thing. The process
is jailed along the same lines as a chroot does it, but with
additional tough restrictions imposed on what the superuser can do.
For all I know, it is safe to hand over the root bit inside a
prison to the customer living in that prison, this is what
it was developed for in fact: "real virtual servers".
Each prison has an ip number associated with it, which all IP
communications will be coerced to use and each prison has its own
hostname.
Needless to say, you need more RAM this way, but the advantage is
that each customer can run their own particular version of apache
and not stomp on the toes of their neighbors.
It generally does what one would expect, but setting up a jail
still takes a little knowledge.
A few notes:
I have no scripts for setting up a jail, don't ask me for them.
The IP number should be an alias on one of the interfaces.
mount a /proc in each jail, it will make ps more useable.
/proc/<pid>/status tells the hostname of the prison for
jailed processes.
Quotas are only sensible if you have a mountpoint per prison.
There are no privisions for stopping resource-hogging.
Some "#ifdef INET" and similar may be missing (send patches!)
If somebody wants to take it from here and develop it into
more of a "virtual machine" they should be most welcome!
Tools, comments, patches & documentation most welcome.
Have fun...
Sponsored by: http://www.rndassociates.com/
Run for almost a year by: http://www.servetheweb.com/
- %fs register is added to trapframe and saved/restored upon kernel entry/exit.
- Per-cpu pages are no longer mapped at the same virtual address.
- Each cpu now has a separate gdt selector table. A new segment selector
is added to point to per-cpu pages, per-cpu global variables are now
accessed through this new selector (%fs). The selectors in gdt table are
rearranged for cache line optimization.
- fask_vfork is now on as default for both UP and SMP.
- Some aio code cleanup.
Reviewed by: Alan Cox <alc@cs.rice.edu>
John Dyson <dyson@iquest.net>
Julian Elischer <julian@whistel.com>
Bruce Evans <bde@zeta.org.au>
David Greenman <dg@root.com>
1:
s/suser/suser_xxx/
2:
Add new function: suser(struct proc *), prototyped in <sys/proc.h>.
3:
s/suser_xxx(\([a-zA-Z0-9_]*\)->p_ucred, \&\1->p_acflag)/suser(\1)/
The remaining suser_xxx() calls will be scrutinized and dealt with
later.
There may be some unneeded #include <sys/cred.h>, but they are left
as an exercise for Bruce.
More changes to the suser() API will come along with the "jail" code.
Get rid of the spl wrapper kludge, it doesn't seem to be needed between
init calls since all that's running is the domain/protocol timers and they
are safe since domain list modifications are splnet() protected (which
blocks the timers)
Interrupts under the new scheme are managed by the i386 nexus with the
awareness of the resource manager. There is further room for optimizing
the interfaces still. All the users of register_intr()/intr_create()
should be gone, with the exception of pcic and i386/isa/clock.c.
1. Make read-ahead work for pread and aio_read.
2. Fix one place where a comparison of uio_offset with -1
wasn't updated to use FOF_OFFSET.
3. Honor O_APPEND in the FOF_OFFSET case.
In addition, use the variable name "ioflag" in both vn_read and
vn_write to avoid possible confusion between the variable "flag"
and the parameter "flags".
Submitted by: Bruce Evans <bde@zeta.org.au> and me
i386 platform boots, it is no longer ISA-centric, and is fully dynamic.
Most old drivers compile and run without modification via 'compatability
shims' to enable a smoother transition. eisa, isapnp and pccard* are
not yet using the new resource manager. Once fully converted, all drivers
will be loadable, including PCI and ISA.
(Some other changes appear to have snuck in, including a port of Soren's
ATA driver to the Alpha. Soren, back this out if you need to.)
This is a checkpoint of work-in-progress, but is quite functional.
The bulk of the work was done over the last few years by Doug Rabson and
Garrett Wollman.
Approved by: core
