whether or not the receive pipe is stopped. This ensures that we
do not attempt to start the same transfer twice, and it allows
ucomstop() to skip the restarting of the read pipe if it was not
originally running, such as when called indirectly from ucomreadcb().
PR: kern/79420
MFC after: 1 day
with E may be called with a shared lock held. This list really could
be made per filesystem if we had any filesystems which differed from
ffs in locking guarantees. VFS itself is not sensitive to this except
where vgone() etc. are concerned.
Sponsored by: Isilon Systems, Inc.
potential lock order reversal. Also, don't unlock the vnode if this
fails, lockmgr has already unlocked it for us.
- Restructure vget() now that vn_lock() does all of VI_DOOMED checking
for us and also handles the case where there is no real lock type.
- If VI_OWEINACT is set, we need to upgrade the lock request to EXCLUSIVE
so that we can call inactive. It's not legal to vget a vnode that hasn't
had INACTIVE called yet.
Sponsored by: Isilon Systems, Inc.
as I'd like to get rid of the vxthread.
- Handle lock requests which don't actually want a lock as this is a
much more convenient place to handle this condition than in vget().
These requests simply want to know that VI_DOOMED isn't set.
- Correct a test at the end of vn_lock, if error !=0 should be
if error == 0, this has been broken since I comitted the VI_DOOMED
changes, but no one ran into it because vget() duplicated this
functionality.
Sponsored by: Isilon Systems, Inc.
getopt() may be called several times - make sure to set optreset
to reset it. Cleanup handling of non-option arguments.
Remove some misleading comments.
Patch: 7.171
Submitted by: Max Okumoto <okumoto@ucsd.edu>
on every line that starts with a dot use a minimal perfect hash
function and a single strcmp() on the first word after the dot
to find out whether it is really a directive call and, if yes, which
one. Then directly dispatch to a handler function for that directive
(or fall through to the dependency handling code). This makes the
directive parse a little bit more strict about the syntax: the directive
word must be followed by a character that is not alphanumerical and not
an underline (making .undefFOO illegal); .endif and .else can only be
followed by comments.
save file was /var/db/entropy, which also happens to
be the directory where the individual entropy files
created by /usr/libexec/save-entropy are stored.
Change the suggestion to be /var/db/entropy-file
instead.
In an error condition where the shutdown file is not
created, the error message accessed a variable that
doesn't exist.
PR: conf/75722
Submitted by: Nicolas Rachinsky <list@rachinsky.de>
rc.conf[.local]. Fix this, and leave the default as 2048.
Update the copyright year to include the present.
Update the assignment of the copyright to be me personally,
instead of "The FreeBSD Project" which is not a legal entity,
and therefore not a proper assignee. My intention remains the
same however, that this code continue to be BSD licensed, and
freely available to anyone that wants it under those terms.
PR: conf/75722
Submitted by: Nicolas Rachinsky <list@rachinsky.de>
layer, but with a twist.
The twist has to do with the fact that Microsoft supports structured
exception handling in kernel mode. On the i386 arch, exception handling
is implemented by hanging an exception registration list off the
Thread Environment Block (TEB), and the TEB is accessed via the %fs
register. The problem is, we use %fs as a pointer to the pcpu stucture,
which means any driver that tries to write through %fs:0 will overwrite
the curthread pointer and make a serious mess of things.
To get around this, Project Evil now creates a special entry in
the GDT on each processor. When we call into Windows code, a context
switch routine will fix up %fs so it points to our new descriptor,
which in turn points to a fake TEB. When the Windows code returns,
or calls out to an external routine, we swap %fs back again. Currently,
Project Evil makes use of GDT slot 7, which is all 0s by default.
I fully expect someone to jump up and say I can't do that, but I
couldn't find any code that makes use of this entry anywhere. Sadly,
this was the only method I could come up with that worked on both
UP and SMP. (Modifying the LDT works on UP, but becomes incredibly
complicated on SMP.) If necessary, the context switching stuff can
be yanked out while preserving the convention calling wrappers.
(Fortunately, it looks like Microsoft uses some special epilog/prolog
code on amd64 to implement exception handling, so the same nastiness
won't be necessary on that arch.)
The advantages are:
- Any driver that uses %fs as though it were a TEB pointer won't
clobber pcpu.
- All the __stdcall/__fastcall/__regparm stuff that's specific to
gcc goes away.
Also, while I'm here, switch NdisGetSystemUpTime() back to using
nanouptime() again. It turns out nanouptime() is way more accurate
than just using ticks(). On slower machines, the Atheros drivers
I tested seem to take a long time to associate due to the loss
in accuracy.
systems that boot with this value at the lowest setting. Change the
default boot config back to "leave frequency as BIOS set it". Also, fix
buglet where acpi_throttle wouldn't be used if p4tcc was present but
disabled by the user.
MFC after: 1 week
a return instruction. (The latter is discouraged by the Opteron
optimization manual because it disables branch prediction for the return
instruction.)
Reviewed by: bde
