connect. This check was added as part of the defense against the "land"
attack, to prevent attacks which guess the ISS from going into ESTABLISHED.
The "src == dst" check will still prevent the single-homed case of the
"land" attack, and guessing ISS's should be hard anyway.
Submitted by: David Borman <dab@bsdi.com>
In vfs_bio.c, remove b_generation count usage,
remove redundant reassignbuf,
remove redundant spl(s),
manage page PG_ZERO flags more correctly,
utilize in invalid value for b_offset until it
is properly initialized. Add asserts
for #ifdef DIAGNOSTIC, when b_offset is
improperly used.
when a process is not performing I/O, and just waiting
on a buffer generally, make the sleep priority
low.
only check page validity in getblk for B_VMIO buffers.
In vfs_cluster, add b_offset asserts, correct pointer calculation
for clustered reads. Improve readability of certain parts of
the code. Remove redundant spl(s).
In vfs_subr, correct usage of vfs_bio_awrite (From Andrew Gallatin
<gallatin@cs.duke.edu>). More vtruncbuf problems fixed.
work reliably yet (I've had panics), but it does seem to occasionally
be able to transmit and receive syntactically-correct packets.
Also fixes one of if_ethersubr.c's legion style bugs, and removes
the hostcache code from standard kernels---the code that depends on it
is not going to happen any time soon, I'm afraid.
Don't try to flush buffers if the drive says it has none.
More error checking and reporting.
Hack: if drive hangs, it can be reset by issuing a mt -f device offline.
I've been able to make several 4G backups. However there is still problems
with some configurations. It is not clear if it is hardware or driver
problems yet.
me any problems until after the previous commit. This problem then
caused a severe case of creeping crud on my diskdrive, and hosed
my system so bad, that I needed to do a complete reinstall. Sorry!!!
I assume that others have manifest this bug.
problems. Tor Egge and others have helped with various VM bugs
lately, but don't blame him -- blame me!!!
pmap.c:
1) Create an object for kernel page table allocations. This
fixes a bogus allocation method previously used for such, by
grabbing pages from the kernel object, using bogus pindexes.
(This was a code cleanup, and perhaps a minor system stability
issue.)
pmap.c:
2) Pre-set the modify and accessed bits when prudent. This will
decrease bus traffic under certain circumstances.
vfs_bio.c, vfs_cluster.c:
3) Rather than calculating the beginning virtual byte offset
multiple times, stick the offset into the buffer header, so
that the calculated offset can be reused. (Long long multiplies
are often expensive, and this is a probably unmeasurable performance
improvement, and code cleanup.)
vfs_bio.c:
4) Handle write recursion more intelligently (but not perfectly) so
that it is less likely to cause a system panic, and is also
much more robust.
vfs_bio.c:
5) getblk incorrectly wrote out blocks that are incorrectly sized.
The problem is fixed, and writes blocks out ONLY when B_DELWRI
is true.
vfs_bio.c:
6) Check that already constituted buffers have fully valid pages. If
not, then make sure that the B_CACHE bit is not set. (This was
a major source of Sig-11 type problems.)
vfs_bio.c:
7) Fix a potential system deadlock due to an incorrectly specified
sleep priority while waiting for a buffer write operation. The
change that I made opens the system up to serious problems, and
we need to examine the issue of process sleep priorities.
vfs_cluster.c, vfs_bio.c:
8) Make clustered reads work more correctly (and more completely)
when buffers are already constituted, but not fully valid.
(This was another system reliability issue.)
vfs_subr.c, ffs_inode.c:
9) Create a vtruncbuf function, which is used by filesystems that
can truncate files. The vinvalbuf forced a file sync type operation,
while vtruncbuf only invalidates the buffers past the new end of file,
and also invalidates the appropriate pages. (This was a system reliabiliy
and performance issue.)
10) Modify FFS to use vtruncbuf.
vm_object.c:
11) Make the object rundown mechanism for OBJT_VNODE type objects work
more correctly. Included in that fix, create pager entries for
the OBJT_DEAD pager type, so that paging requests that might slip
in during race conditions are properly handled. (This was a system
reliability issue.)
vm_page.c:
12) Make some of the page validation routines be a little less picky
about arguments passed to them. Also, support page invalidation
change the object generation count so that we handle generation
counts a little more robustly.
vm_pageout.c:
13) Further reduce pageout daemon activity when the system doesn't
need help from it. There should be no additional performance
decrease even when the pageout daemon is running. (This was
a significant performance issue.)
vnode_pager.c:
14) Teach the vnode pager to handle race conditions during vnode
deallocations.
on the IOAPIC being connected to the 8254 timer interrupt.
Verify that timer interrupts are delivered. If they aren't, attempt
a fallback to mixed mode (i.e. routing the timer interrupt via the 8259 PIC).
Gee, I wish there was a better way to run makesyscalls.sh so that
a make world finds missing things like this. Running it manually
sucks.
Pointed out by: Peter Dufault
unsigned integral type. Changing it doesn't seem to cause any
sign extension bugs in /usr/src. In the kernel, this is partly
because `struct speedtab' and its lookup function are too bogus
to use speed_t's for speeds - they use ints.
Reminded by: PR 5786
previous commit. Opportunities to clean pages were often missed,
and leaving of the idle state was sometimes delayed until the next
interrupt (after any that occurred while cleaning).
Fixed an unstaticization, a syntax error and a style bug in the
previous commit.
of a disk, because that slice does not exist, try again mounting from the
compatability slice.
This handles the case where a disk has been initialised by 'disklabel
auto', which places a bogus and invalid slice entry on the disk.
The bootstrap is not smart enough to reject this slice, and pretends to
boot from it. Believing the the bootstrap at this point is unwise.
Booting from non-'wd' disks thus prepared is still broken, as
'disklabel -rwB xdN auto' does not initialise the disk type field, and
the bootstrap mistakenly claims that the disk is handled by 'wd'.
Behaviour is now consistent with DEVFS expected characteristics.
(and even run). These files don't necessarily make sense for a
FreeBSD/Alpha kernel build. That will come later and these files
will be changed accordingly.
the other syscall files are generated into. This new file is to be
included by src/lib/libc/sys/Makefile.inc to automatically pick up
syscall names.
The other file, netbsd_syscall.mk, is the hand-generated NetBSD
equivalent to be included by src/lib/libc/sys/Makefile.inc when
_NETBSD_SYSCALLS is defined during the build of libc/libc_r.
during the libc/libc_r to automatically pick up syscall names on
the assumption that default asm code needs to generated for them.
In the up-coming changes to the libc makefiles, there is the option
to provide a machine dependent asm source file which will turn off
the automatic generation of the default. There is also an option
to just stop code being generated for a syscall. In most cases,
though, the default asm code is all that is required, so this
change makes that the most convenient was to do business.
Idea suggested by: bde
Changes to support building with _POSIX_SOURCE set to 199309L:
1. Add sys/_posix.h to handle those preprocessor defs that POSIX
says have effects when defined before including any header files;
2. Change POSIX4_VISIBLE back to _POSIX4_VISIBLE
3. Add _POSIX4_VISIBLE_HISTORICALLY for pre-existing BSD features now
defined in POSIX. These show up when:
_POSIX_SOURCE and _POSIX_C_SOURCE are not set or
_POSIX_C_SOURCE is set >= 199309L
and vanish when:
_POSIX_SOURCE is set or _POSIX_C_SOURCE is < 199309L.
4. Explain these in man 9 posix4;
5. Include _posix.h and conditionalize on new feature test.
slice number passed in by the bootblocks. This means the kernel will
not use the compatability slice to obtain the root filesystem when
booting from a sliced disk.
Use the extraction macros from reboot.h rather than stating them in full
again.
1) When freeing pages, it is a good idea to protect them off.
(This is probably gratuitious, but good form.)
2) Allow collapsing pages in the backing object that are
PQ_CACHE. This will improve memory utilization.
3) Correct the collapse code so that pages that were on the
cache queue are moved to the inactive queue. This is
done when pages are marked dirty (so that those pages
will be properly paged out instead of freed), so that
cached pages will not be paradoxically marked dirty.
has been some bitrot and incorrect assumptions in the vfs_bio code. These
problems have manifest themselves worse on NFS type filesystems, but can
still affect local filesystems under certain circumstances. Most of
the problems have involved mmap consistancy, and as a side-effect broke
the vfs.ioopt code. This code might have been committed seperately, but
almost everything is interrelated.
1) Allow (pmap_object_init_pt) prefaulting of buffer-busy pages that
are fully valid.
2) Rather than deactivating erroneously read initial (header) pages in
kern_exec, we now free them.
3) Fix the rundown of non-VMIO buffers that are in an inconsistent
(missing vp) state.
4) Fix the disassociation of pages from buffers in brelse. The previous
code had rotted and was faulty in a couple of important circumstances.
5) Remove a gratuitious buffer wakeup in vfs_vmio_release.
6) Remove a crufty and currently unused cluster mechanism for VBLK
files in vfs_bio_awrite. When the code is functional, I'll add back
a cleaner version.
7) The page busy count wakeups assocated with the buffer cache usage were
incorrectly cleaned up in a previous commit by me. Revert to the
original, correct version, but with a cleaner implementation.
8) The cluster read code now tries to keep data associated with buffers
more aggressively (without breaking the heuristics) when it is presumed
that the read data (buffers) will be soon needed.
9) Change to filesystem lockmgr locks so that they use LK_NOPAUSE. The
delay loop waiting is not useful for filesystem locks, due to the
length of the time intervals.
10) Correct and clean-up spec_getpages.
11) Implement a fully functional nfs_getpages, nfs_putpages.
12) Fix nfs_write so that modifications are coherent with the NFS data on
the server disk (at least as well as NFS seems to allow.)
13) Properly support MS_INVALIDATE on NFS.
14) Properly pass down MS_INVALIDATE to lower levels of the VM code from
vm_map_clean.
15) Better support the notion of pages being busy but valid, so that
fewer in-transit waits occur. (use p->busy more for pageouts instead
of PG_BUSY.) Since the page is fully valid, it is still usable for
reads.
16) It is possible (in error) for cached pages to be busy. Make the
page allocation code handle that case correctly. (It should probably
be a printf or panic, but I want the system to handle coding errors
robustly. I'll probably add a printf.)
17) Correct the design and usage of vm_page_sleep. It didn't handle
consistancy problems very well, so make the design a little less
lofty. After vm_page_sleep, if it ever blocked, it is still important
to relookup the page (if the object generation count changed), and
verify it's status (always.)
18) In vm_pageout.c, vm_pageout_clean had rotted, so clean that up.
19) Push the page busy for writes and VM_PROT_READ into vm_pageout_flush.
20) Fix vm_pager_put_pages and it's descendents to support an int flag
instead of a boolean, so that we can pass down the invalidate bit.
put alot of it's context into a data structure. This allows
significant shortening of its codepath, and will significantly
decrease it's cache footprint.
Also, add some stats to vmmeter. Note that you'll have to
rebuild/recompile vmstat, systat, etc... Otherwise, you'll
get "very interesting" paging stats.
f00f_hack has run.
Use the global r_idt descriptor in f00f_hack when in SMP mode,
so the APs find the relocated interrupt descriptor table.
Submitted by: Partially from David A Adkins <adkin003@tc.umn.edu>
dynamically depending on the line speed(s). This should give the old
sizes and watermarks until drivers are changed.
Display the input watermarks in pstat and sicontrol.
Fix for RTPRIO scheduler to eliminate invalid context switches.
POSIX.4 headers and sysctl variables. Nothing should change
unless POSIX4 is defined or _POSIX_VERSION is set to 199309.
interrupts are masked, and EOI is sent iff the corresponding ISR bit
is set in the local apic. If the CPU cannot obtain the interrupt
service lock (currently the global kernel lock) the interrupt is
forwarded to the CPU holding that lock.
Clock interrupts now have higher priority than other slow interrupts.
the signal handling latency for cpu-bound processes that performs very
few system calls.
The IPI for forcing an additional software trap is no longer dependent upon
BETTER_CLOCK being defined.
than rolling it's own. This means that it now uses the "safe"
exec_map_first_page() to get the ld.so headers rather than risking a panic
on a page fault failure (eg: NFS server goes down).
Since all the ELF tools go to a lot of trouble to make sure everything
lives in the first page for executables, this is a win. I have not seen
any ELF executable on any system where all the headers didn't fit in the
first page with lots of room to spare.
I have been running variations of this code for some time on my pure ELF
systems.
a complement to all ops that return a vpp, VFS_VRELE. This is
initially only for file systems that implement the following ops
that do a WILLRELE:
vop_create, vop_whiteout, vop_mknod, vop_remove, vop_link,
vop_rename, vop_mkdir, vop_rmdir, vop_symlink
This is initial DNA that doesn't do anything yet. VFS_VRELE is
implemented but not called.
A default vfs_vrele was created for fs implementations that use the
standard vnode management routines.
VFS_VRELE implementations were made for the following file systems:
Standard (vfs_vrele)
ffs mfs nfs msdosfs devfs ext2fs
Custom
union umapfs
Just EOPNOTSUPP
fdesc procfs kernfs portal cd9660
These implementations may change as VOP changes are implemented.
In the next phase, in the vop implementations calls to vrele and the vrele
part of vput will be moved to the top layer vfs_vnops and made visible
to all layers. vput will be replaced by unlock in these cases. Unlocking
will still be done in the per fs layer but the refcount decrement will be
triggered at the top because it doesn't hurt to hold a vnode reference a
little longer. This will have minimal impact on the structure of the
existing code.
This will only be done for vnode arguments that are released by the various
fs vop implementations.
Wider use of VFS_VRELE will likely require restructuring of the code.
Reviewed by: phk, dyson, terry et. al.
Submitted by: Michael Hancock <michaelh@cet.co.jp>
|In the process of evaluating the getpages/putpages issues I discovered
|that mmap on MSDOSFS does not work. This is because I blindly merged
|NetBSD changes in msdosfs_bmap and msdosfs_strategy. Apparently, their
|blocksize is always DEV_BSIZE (even in files), while in FreeBSD
|blocksize in files is v_mount->mnt_stat.f_iosize (i.e. clustersize in
|MSDOSFS case). The patch is below.
Submitted by: Dmitrij Tejblum <dima@tejblum.dnttm.rssi.ru>
It does endeed work, but there is still some problems to solve.
I get a "nonrecovered data error" from time to time, but besides
this it has backed up several Gigs allready.
Please report any success/failure directly to me.
Thanks to Warner Losh for providing a drive to use in writing
this driver!
2) Do not unnecessarily force page blocking when paging
pages out.
3) Further improve swap pager performance and correctness,
including fixing the paging in progress deadlock (except
in severe I/O error conditions.)
4) Enable vfs_ioopt=1 as a default.
5) Fix and enable the page prezeroing in SMP mode.
All in all, SMP systems especially should show a significant
improvement in "snappyness."
it runs at a constant frequency. This was less of an issue before,
because the TSC only interpolated in the HZ intervals, but now where
the timecounter is used all the way, this becomes much more visible.
Nit: Fix a printf which triggered the bde-filter.
since there might be permanent entries still left after
calls to DeleteLink (it will be nullified by DeleteLink
if all entries are deleted, won't it ?)
2) in PacketAliasSetAddress, set the aliasing address
even when PKT_ALIAS_RESET_ON_ADDR_CHANGE is in effect.
Just don't clean up links in this case.
Submitted by: Ari Suutari <ari@suutari.iki.fi>
via: Charles Mott <cmott@srv.net>
PR: 5041
- 'mv longnamedfile1 longnamedfile2' would cause longnamedfile2 to lose its
long name.
- Long names have trailing spaces/dots stripped for lookup as well as
assignment.
- A lockup when the mdsosfs was accessed from within the Linux emulator is fixed.
- A bug whereby long filenames were recognised by Microsoft operating systems but
not FreeBSD is fixed.
Submitted by: Dmitrij Tejblum <dima@tejblum.dnttm.rssi.ru>
These diffs implement the first stage of a VOP_{GET|PUT}PAGES pushdown
for local media FS's.
See ffs_putpages in /sys/ufs/ufs/ufs_readwrite.c for implementation
details for generic *_{get|put}pages for local media FS's. Support
is trivial to add for any FS that formerly relied on the default
behaviour of the vnode_pager in in EOPNOTSUPP cases (just copy the
ffs_getpages() code for the FS in question's *_{get|put}pages).
Obviously, it would be better if each local media FS implemented a
more optimal method, instead of calling an exported interface from
the /sys/vm/vnode_pager.c, but this is a necessary first step in
getting the FS's to a point where they can be supplied with better
implementations on a case-by-case basis.
Obviously, the cd9660_putpages() can be rather trivial (since it
is a read-only FS type 8-)).
A slight (temporary) modification is made to print a diagnostic message
in the case where the underlying filesystem attempts to engage in the
previous behaviour. Failure is likely to be ungraceful.
Submitted by: terry@freebsd.org (Terry Lambert)
Fixed pedantic semantics errors (in ANSI C, static arrays must have
a size, and static objects should be consistently declared as static
unless you know more than anyone should have to know about the
linkage rules).
There is now less need for the vfs.usermount sysctl. msdosfs already
has this change, modulo a missing LK_RETRY, via NetBSD. At least
ext2fs is missing this and many other changes from Lite2.
Obtained from: Lite2
times consistently wrong (up to 1 tick too late), but recent changes
fixed the setting of the main clock, making other times inconsistent.
The inconsistencies tended to show up as a negative resource usage
for the process that set the time.
Fixed the check for setting the clock backwards. A stale timestamp
(`time') was checked, so it was possible to set the clock backwards
by up to almost 1 tick. Until recently, this bug was compensated
for by setting the clock consistently wrong.
Merged the comment about setting the clock backwards from Lite2.
Removed latency micro-optimizations/speed pessimizations in settime().
microtime() and set_timecounter() are relatively expensive, and
they must be called together with clock updates blocked to get a
consistent `delta', so significant latency optimizations are not
possible.
Removed some stale comments.
sources can't include it. However, until recently it was included
by <sys/stat.h>, so it should have been (almost) entirely inside
_POSIX_SOURCE ifdefs for <sys/stat.h> to be (almost) POSIX.1 conformant,
but it was only about half inside _POSIX_SOURCE ifdefs.
longstanding namespace pollution. The need for the pollution
(unconditional use of timespecs) went away in the first round of
Lite2 merges (rev.1.7 for stat.h), but <sys.time.h> was still
unconditionally included, and a stale comment about the need for
the pollution was not removed.
