BUS_DMASYNC_ definitions remain as before. The does not change the ABI,
and reverts the API to be a bit more compatible and flexible. This has
survived a full 'make universe'.
Approved by: re (bmah)
used by DDB and we cannot know in advance whether it's save to
sleep. It often enough isn't. We may want to pre-allocate space
to cover the most common cases without having to use malloc at
all, but that requires some analysis. We leave that for later.
Approved by: re@ (blanket)
o If the address was not within user space we jumped to fusufault
where we would clear pcb_onfault and return 0. There are two
bugs here:
1. We never got to the point where we assigned the address of
pcb_onfault to r15, which means that we would clobber some
random memory location, including I/O space or ROM.
2. We're supposed to return -1 on error.
o Make sure we have proper memory ordering for setting pcb_onfault,
doing the memory access to user space and clearing pcb_onfault.
For the fu* family of functions this means that we need a mf
instruction, because we don't have acquire semantics on stores
and release semantics on loads (hence st;ld cannot be ordered
without intermediate mf).
While here, implement casuptr() so that we are a (small) step
closer to supporting libthr and deobfuscate the non-implementation
of {f|s}uswintr.
Approved by: re@ (blanket)
VM_ALLOC_INTERRUPT to VM_ALLOC_SYSTEM. There was no mention of
this in commit log as it was considered harmless. Guess what:
it does harm. WITNESS showed that we can not safely grab the
page queue lock in vm_page_alloc() in all cases as we may have
to sleep on it. Revert the request to VM_ALLOC_INTERRUPT to
circumvent this. We panic if vm_page_alloc returns 0. I'm not
entirely happy about this, but we have bigger fish to fry.
Approved by: re@ (blanket)
aic79xx.c:
In ahd_handle_ign_wide_residue():
o Use SCB_XFERLEN_ODD SCB field to determine transfer
"oddness" rather than the DATA_COUNT_ODD logic.
SCB_XFERLEN_ODD is toggled on every ignore wide
residue message so that multiple ignore wide residue
messages for the same transaction are properly supported.
o If the sg list has been exausted, the sequencer
doesn't bother to update the residual data count
since it is known to be zero. Perform the zeroing
manually before calculating the remaining data count.
o Use multibyte in/out macros instead of shifting/masking
by hand.
aic79xx_inline.h:
In ahd_setup_scb_common(), setup the SCB_XFERLEN_ODD field.
aic79xx.reg:
Use the SCB_TASK_ATTRIBUTE field as a bit field in the
non-packetized case. We currently only define one bit,
SCB_XFERLEN_ODD.
Remove the ODD_SEG bit field that was used to carry the odd
transfer length information through the SG cache. This
is obviated by SCB_XFERLEN_ODD field.
Remove the DATA_COUNT_ODD scratch ram byte that was used
dynamicaly compute data transfer oddness. This is obviated
by SCB_XFERLEN_ODD field.
aic79xx.seq:
Remove all updates to the DATA_COUNT_ODD scratch ram field.
Remove all uses of ODD_SEG. These two save quite a few
sequencer instructions.
Use SCB_XFERLEN_ODD to validate the end of transfer
ignore wide residue message case.
aic7xxx.c:
In ahc_handle_ign_wide_residue():
o Use SCB_XFERLEN_ODD SCB field to determine transfer
"oddness" rather than the DATA_COUNT_ODD logic.
SCB_XFERLEN_ODD is toggled on every ignore wide
residue message so that multiple ignore wide residue
messages for the same transaction are properly supported.
o If the sg list has been exausted, the sequencer
doesn't bother to update the residual data count
since it is known to be zero. Perform the zeroing
manually before calculating the remaining data count.
o Ensure that SG_LIST_NULL is cleared in the
residual sg pointer for "mid-transfer" ignore
wide residue cases.
o Use multibyte in/out macros instead of shifting/masking
by hand.
aic7xxx.h:
Modify the SCB_GET_LUN() macro to mask the lun hardware
SCB field with LID. This leaves two bits in the LUN
field that can be used for other purposes.
aic7xxx.reg:
Change LID to be 0x3F. This is the maximum supported
lun size for non-packetized SCSI. Map the top bit
of the lun to SCB_XFERLEN_ODD. The host must set
this bit whenever a transfer is an odd length.
Remove the ODD_SEG bit field that was used to carry the odd
transfer length information through the SG cache. This
is obviated by SCB_XFERLEN_ODD field.
Remove the DATA_COUNT_ODD scratch ram byte that was used
dynamicaly compute data transfer oddness. This is obviated
by SCB_XFERLEN_ODD field.
aic7xxx.seq:
Be more careful in our handling of the SCB_LUN field. It
must be masked with LID if only lun information is desired.
Remove all updates to the DATA_COUNT_ODD scratch ram field.
Remove all uses of ODD_SEG. These two save quite a few
sequencer instructions.
Use SCB_XFERLEN_ODD to validate the end of transfer
ignore wide residue message case.
aic7xxx_inline.h:
In ahc_queue_scb(), setup the SCB_XFERLEN_ODD field.
Approved by: RE
FAILDIS in the SEQCTL register, not the HCNTRL register.
aic7xxx.c:
Remeber SEQCTL settings in the "seqctl" field of our
softc. seqctl defaults to just having FASTMODE set,
but the bus attachments can override this.
aic7xxx.h:
Add the seqctl softc field.
aic7xxx_pci.c:
Update the seqctl softc field and manually update SEQCTL
when to many PCI errors occur
Approved by: RE
to be more efficient by having the sequencer copy the
single byte of valid lun data into the long lun field.
aic79xx.c:
Memset our hardware SCB to 0 so that untouched
fields don't confuse diagnostic output. With the
old method for handling the Rev A bug, if the long
lun field was not 0, this could result in bogus
lun information being sent to drives.
Use the same SCB transfer size for all chip types
now that the long lun is not DMA'ed to the chip.
aic79xx.seq:
Add code to copy lun information for Rev.A hardware.
aic79xx_inline.h:
Remove host update of the long_lun field on every
packetized command.
Sort IDs based on chip type.
Remove IROC IDs. We'll switch to using the IROC masks
if/when we want to start attaching to IROC controllers.
Approved by: RE
either COMMENT or DESCR from the command line. When a port is
installed, one gets both +COMMENT and +DESCR files with a trailing
'\n' character. However, +COMMENT does not contain a trailing '\n'
when it is installed from a package due to this behavior of pkg_create.
Therefore, make sure it behaves exactly the same regardless of
where got its information; either command line or files. The modified
functions are used by pkg_create.
PR: 52097
Reviewed by: bento, kris,
portmgr, re,
Michael Nottebrock <michaelnottebrock@gmx.net>,
Martin Horcicka <horcicka@FreeBSD.cz>
Approved by: re (scottl)
MFC after: 1 week
thread is not dead, the join loop is guaranteed to execute at least
once, so there is no need to pick up the thread list lock after
we return from suspenstion only to release it after the loop.
Approved by: re/blanket libthr
because we could fail due to a small buffer and loop and rerun. If this
happens, then the vsnprintf() will have already taken the arguments off
the va_list. For i386 and others, this doesn't matter because the
va_list type is a passed as a copy. But on powerpc and amd64, this is
fatal because the va_list is a reference to an external structure that
keeps the vararg state due to the more complicated argument passing system.
On amd64, arguments can be passed as follows:
First 6 int/pointer type arguments go in registers, the rest go on
the memory stack.
Float and double are similar, except using SSE registers.
long double (80 bit precision) are similar except using the x87 stack.
Where the 'next argument' comes from depends on how many have been
processed so far and what type it is. For amd64, gcc keeps this state
somewhere that is referenced by the va_list.
I found a description that showed the va_copy was required here:
http://mirrors.ccs.neu.edu/cgi-bin/unixhelp/man-cgi?va_end+9
The single unix spec doesn't mention va_copy() at all.
Anyway, the problem was that the sysctl kern.geom.conf* nodes would panic
due to walking off the end of the va_arg lists in vsnprintf. A better fix
would be to have sbuf_vprintf() use a single pass and call kvprintf()
with a callback function that stored the results and grew the buffer
as needed.
Approved by: re (scottl)
joined and then the joiner thread. There isn't an easy (sane?) way
to make it use the correct order without introducing races involving
the target thread and finding which (active or dead) list it is on. So,
after locking the canceled thread it will try to lock the joined thread
and if it fails release the first lock and try again from the top.
Introduce a new function, _spintrylock, which is simply a wrapper arround
umtx_trylock(), to help accomplish this.
Approved by: re/blanket libthr
Modify the thread creation and thread searching routine
to lock the thread lists with the new locks instead of GIANT_LOCK.
Approved by: re/blanket libthr
list is protected by a spinlock_t, but the dead list uses a pthread_mutex
because it is necessary to synchronize other threads with the garbage
collector thread. Lock/Unlock macros are used so it's easier to make
changes to the locks in the future.
The 'dead thread list' lock is intended to replace the gc mutex.
This doesn't have any practical ramifications. It simply makes it
clearer what the purpose of the lock is. The gc will use this lock,
instead of the gc mutex, to synchronize access to the dead list with
other threads.
Modify _pthread_exit() to use these two new locks instead of GIANT_LOCK,
and also to properly lock and protect thread state changes,
especially with respect to a joining thread.
The gc thread was also re-arranged to be more organized and less nested.
_pthread_join() was also modified to use the thread list locks. However,
locking and unlocking here needs special care because a thread could find
itself in a position where it's joining an exiting thread that is
waiting on the dead list lock, which this thread (joiner) holds. If the
joiner doesn't take care to lock *and* unlock in the same order they
(the joiner and the joinee) could deadlock against each other.
Approved by: re/blanket libthr
pthread_cond_t) internaly in addition to the low-level spinlock_t. The
garbage collector mutex and condition variable are two such examples. This
might lead to critical sections nested within critical sections. Implement
a reference counting mechanism so that signals are masked only on the first
entry and unmasked on the last exit.
I'm not sure I like the idea of nested critical sections, but if
the library is going to use the pthread primitives it might be necessary.
Approved by: re/blanket libthr
error) on amd64 when doing pointer subtraction. This bug is already
fixed in gcc-3.3 (waiting for after the branch), and the hack will be
backed out at the first opportunity. This is in the ipv6 code path.
Approved by: re (scottl)
is not pretty, but it fixes the code so that it no longer violates the
vnode locking rules in the VFS API and doesn't trip any of the locking
assertions enabled by the DEBUG_VFS_LOCKS kernel configuration option.
There is one report that this patch fixed a "locking against myself"
panic on an NFS server that was tripped by a diskless client.
Approved by: re (scottl)
structure, which is new to the 82550 and 82551, is used to transmit
a packet. This appears to fix the packet truncation problem that was
observed when using 82550-based fxp cards to transmit ICMP or fragmented
UDP packets of certain lengths which only had one to three bytes in the
second and final mbuf of the packet. This matches a note in the "Intel
8255x 10/100 Mbps Ethernet Controller Family Open Source Software Developer
Manual", which says that the hardware parse bit should be set when sending
these types of packets.
There have also been unconfirmed reports of similar problems when
transmitting TCP packets, which should not be affected by the above
mentioned change because the hardware parse bit was already being set
if the stack requested hardware checksumming of the packet. If the
problem remains, the use of the IPCB structure can be disabled to
cause the driver to fall back to using the older 82559 interface with
82550-based cards by setting
hint.fxp.UNIT_NUMBER.ipcbxmit_disable
to a non-zero value at boot time, or using kenv to set this variable
before using kldload to load the fxp driver.
Approved by: re (jhb)
kernel's VA regions, we cannot limit the use of break-based
syscalls to user mode only. The signal trampolines are in the
gateway page, which is mapped into the process address space in
region 5 and thus is kernel space.
We don't special case the gateway page here. Allow break-based
syscalls from anywhere in the kernel VA space.
Approved by: re@ (blanket)
set on realtek cards, but they work without it (and don't work with
it). The standard seems to imply that this is just a hint anyway, so
this should be harmless. It doesn't appear to be set on any other
cardbus cards that I have (or have seen).
This should make the rl based CardBus cards work again. I've been
running it for about a month now.
Approved by: re@ (jhb)
to userland with interrupts disabled until we restore PSR. However,
it has been observed that interrupts do actually happen before they
are enabled again. This is a bit surprising and I don't know yet
what's going on exactly. Nevertheless, the code was not crafted
carefully enough to allow interrupts to happen and we could
clobber the kernel stack of another thread when interrupts did
happen.
This is what happens: we restore the (memory) stack pointer (sp)
and the register stack base prior to restoring ar.k6 and ar.k7.
This is not a problem if interrupts don't happen between setting
sp/ar.bspstore and ar.k6/ar.k7. Alas, interrupts can happen.
Since sp/ar.bspstore already point to the userland stacks, we
need to switch to the kernel stack in interrupt. However, ar.k6
and ar.k7 have not been set, which means that we were switching
to some unrelated kstack and happily clobbered the trapframe
present there if the thread to which the kstack belonged was
in kernel mode or otherwise we could have our trapframe clobbered
if that other thread enters the kernel. Nasty either way.
We now carefully restore ar.k6 prior to restoring ar.bspstore and
likewise for ar.k7 and sp. All we need is the guarantee that an
interrupt does not clobber ar.k6 or ar.k7 before we're back in
userland. That has been achieved by restoring ar.k6/ar.k7
unconditionally (see exception.s)
While here, remove the disabling of interrupts on EPC entry. It
was added as a way to "resolve" the crashes until it was understood
what was going on. I think I achieved the latter, so we can remove
the patch. Note that setting up a trapframe with interrupts
enabled has it's own share of corner cases, but it's better to
properly fixed those than to keep a mostly wrong patch around
because we're afraid to remove it...
Approved by: re@ (blanket)
PSR only to achieve setting PSR.i back to it's previous value. It
makes it impossible to change any of the 30+ other unrelated bits
when done between intr_disable() and intr_restore(). That's bad.
Instead have intr_disable() return 1 when interrupts were previously
enabled and 0 otherwise and only enable interrupts in intr_restore()
when given a non-0 value.
This change specifically disallows using intr_restore() to disable
interrupts. The reason is simple: interrupts only need to be restored
after they are being disabled, which means that intr_restore() is
called with interrupts disabled and we only need to enable them if
they were previously enabled.
This change does not fix any bugs, other than that it bugged me...
Approved by: re@ (blanket)
and user mode. We need to take into account that the EPC syscall path
introduces a grey area in which one can argue either way, including a
third: neither.
We now use the region in which the IP address lies. Regions 5, 6 and 7
are kernel VA regions and if the IP lies any any of those regions we
assume we're in kernel mode. Hence, we can be in kernel mode even if
we're not on the kernel stack and/or have user privileges. There're
gremlins living in the twilight zone :-)
For the EPC syscall path this particularly means that the process
leaves user mode the moment it calls into the gateway page. This
makes the most sense because from a process' point of view the call
represents a request to the kernel for some service and that service
has been performed if the call returns. With the metric we picked,
this also means that we're back in user mode IFF the call returns.
Approved by: re@ (blanket)
give the cvs tree a surviving a 'make world'. One of the two diff chunks
is already in gcc-3.3, the other has been committed to gcc's HEAD and
is in the pipeline for gcc-3.3.1 (but has not been committed yet).
The first chunk simplifies an excessively complex assembler statement
when generating switch jump tables. The use of '.' causes as(1) to choke
on big files. Use a simpler form instead. This is only an issue for
TARGET_64BIT mode.
The second chunk fixes an internal compiler error when compiling
libc/stdio/vfprinf.c. While this is supposedly only an issue for
64 bit mode, it does touch the 32 bit i386 code paths, so this patch
is only applied for TARGET_ARCH == amd64 to keep the risks down.
Breaking gcc at the 11th hour would suck.
This will be removed when it is time to import gcc-3.3.
Discussed with: kan
Approved by: re (jhb)
when returning from an interrupt. Both registers are used on interrupt
to switch to the right kernel stack, but other than that they are not
used. This means we only have to make sure they contain proper values
while in user mode. As such, we conditionally restored these registers
based on whether we returned to userland or not. A nice property of
conditionally restoring ar.k6 and ar.k7 is that it introduces two
invariants: ar.k6 always points to the bottom of the kernel stack and
ar.k7 always points to the top of the kernel stack (immediately below
the PCB we have there).
However, the EPC syscall path introduces an irregularity: there's no
"thin red line" between user and kernel. There's a grey area that's a
couple of instructions wide. Any interruption in that grey area is
bound to see an inconsistent state. One such state is that we're in
kernel space for all practical purposes, but we still need to have
ar.k6 and ar.k7 restored as if we're in userland.
Thus: restore ar.k6 and ar.k7 unconditionally at the cost of losing
a valuable invariant. Both registers now hold the extend of the
usable portion of the kernel stack at any interrupt nesting, which
when in userland mean the bottom and the top of the kstack.
