15 Feb, 2006
1 commit
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Currently, copy-on-write may change the physical address of a page even if the
user requested that the page is pinned in memory (either by mlock or by
get_user_pages). This happens if the process forks meanwhile, and the parent
writes to that page. As a result, the page is orphaned: in case of
get_user_pages, the application will never see any data hardware DMA's into
this page after the COW. In case of mlock'd memory, the parent is not getting
the realtime/security benefits of mlock.In particular, this affects the Infiniband modules which do DMA from and into
user pages all the time.This patch adds madvise options to control whether memory range is inherited
across fork. Useful e.g. for when hardware is doing DMA from/into these
pages. Could also be useful to an application wanting to speed up its forks
by cutting large areas out of consideration.Signed-off-by: Michael S. Tsirkin
Acked-by: Hugh Dickins
Cc: Michael Kerrisk
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
04 Feb, 2006
1 commit
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"[PATCH] m68knommu: fix find_next_zero_bit in bitops.h" fixed a typo in
m68knommu implementation of find_next_zero_bit().grep(1) shows that cris, frv, h8300, v850 are also affected.
Signed-off-by: Alexey Dobriyan
Cc: Mikael Starvik
Cc: David Howells
Cc: Yoshinori Sato
Cc: Miles Bader
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
19 Jan, 2006
1 commit
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Handle TIF_RESTORE_SIGMASK as added by David Woodhouse's patch entitled:
[PATCH] 2/3 Add TIF_RESTORE_SIGMASK support for arch/powerpc
[PATCH] 3/3 Generic sys_rt_sigsuspendIt does the following:
(1) Declares TIF_RESTORE_SIGMASK for FRV.
(2) Invokes it over to do_signal() when TIF_RESTORE_SIGMASK is set.
(3) Makes do_signal() support TIF_RESTORE_SIGMASK, using the signal mask saved
in current->saved_sigmask.(4) Discards sys_rt_sigsuspend() from the arch, using the generic one instead.
(5) Makes sys_sigsuspend() save the signal mask and set TIF_RESTORE_SIGMASK
rather than attempting to fudge the return registers.(6) Makes sys_sigsuspend() return -ERESTARTNOHAND rather than looping
intrinsically.(7) Makes setup_frame(), setup_rt_frame() and handle_signal() return 0 or
-EFAULT rather than true/false to be consistent with the rest of the
kernel.Due to the fact do_signal() is then only called from one place:
(8) Make do_signal() no longer have a return value is it was just being
ignored; force_sig() takes care of this.(9) Discards the old sigmask argument to do_signal() as it's no longer
necessary.This patch depends on the FRV signalling patches as well as the
sys_rt_sigsuspend patch.Signed-off-by: David Howells
Signed-off-by: David Woodhouse
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
13 Jan, 2006
1 commit
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{get,put}_thread_info() were introduced in 2.5.4 and never
had been called by anything in the tree.Signed-off-by: Al Viro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
11 Jan, 2006
1 commit
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Most arches copied the i386 ioctl.h. Combine them into a generic header.
Signed-off-by: Brian Gerst
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
10 Jan, 2006
2 commits
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add the per-arch mutex.h files for the remaining architectures.
We default to asm-generic/mutex-dec.h, because that performs
quite well on most arches. Arches that do not have atomic
decrement/increment instructions should switch to mutex-xchg.h
instead. Arches can also provide their own implementation for
the mutex fastpath primitives.Signed-off-by: Arjan van de Ven
Signed-off-by: Ingo Molnar -
add atomic_xchg() to all the architectures. Needed by the new mutex code.
Signed-off-by: Ingo Molnar
Signed-off-by: Arjan van de Ven
09 Jan, 2006
5 commits
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Fix a number of miscellanous items:
(1) Declare lock sections in the linker script.
(2) Recurse in the correct manner in the arch makefile.
(3) asm/bug.h requires asm/linkage.h to be included first. One C file puts
asm/bug.h first.(4) Add an empty RTC header file to avoid missing header file errors.
(5) sg_dma_address() should use the dma_address member of a scatter list.
(6) Add trivial pci_unmap support.
(7) Add pgprot_noncached()
(8) Discard u_quad_t.
(9) Use ~0UL rather than ULONG_MAX in unistd.h in case the latter isn't
declared.(10) Add an empty VGA header file to avoid missing header file errors.
(11) Add an XOR header file to use the generic XOR stuff.
Signed-off-by: David Howells
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Make the get_user macro cast the source pointer to an appropriate type for the
specified size.Signed-off-by: David Howells
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Add stubs for FRV module support.
Signed-off-by: David Howells
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Supply various I/O access primitives that are missing for the FRV arch:
(*) mmiowb()
(*) read*_relaxed()
(*) ioport_*map()
(*) ioread*(), iowrite*(), ioread*_rep() and iowrite*_rep()
(*) pci_io*map()
(*) check_signature()
The patch also makes __is_PCI_addr() more efficient.
Signed-off-by: David Howells
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Drop support for 8-bit and 16-bit xchg and cmpxchg emulation and implements
32-bit xchg with the SWAP/SWAPI instruction.Signed-off-by: David Howells
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
07 Jan, 2006
4 commits
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The attached patch improves the signal handling:
(1) It makes do_signal() static as it isn't called from anywhere outside of
the arch code.(2) It removes the regs argument to all the static functions within that file,
using __frame instead (which is the same thing held in a global register).Signed-off-by: David Howells
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The attached patch implements futex operations for the FRV architecture. The
operations are applicable to both MMU and no-MMU modes; though the EFAULT
handling will be a little bit of wasted space on the latter.Signed-off-by: David Howells
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Several counters already have the need to use 64 atomic variables on 64 bit
platforms (see mm_counter_t in sched.h). We have to do ugly ifdefs to fall
back to 32 bit atomic on 32 bit platforms.The VM statistics patch that I am working on will also make more extensive
use of atomic64.This patch introduces a new type atomic_long_t by providing definitions in
asm-generic/atomic.h that works similar to the c "long" type. Its 32 bits
on 32 bit platforms and 64 bits on 64 bit platforms.Also cleans up the determination of the mm_counter_t in sched.h.
Signed-off-by: Christoph Lameter
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Here is the patch to implement madvise(MADV_REMOVE) - which frees up a
given range of pages & its associated backing store. Current
implementation supports only shmfs/tmpfs and other filesystems return
-ENOSYS."Some app allocates large tmpfs files, then when some task quits and some
client disconnect, some memory can be released. However the only way to
release tmpfs-swap is to MADV_REMOVE". - Andrea ArcangeliDatabases want to use this feature to drop a section of their bufferpool
(shared memory segments) - without writing back to disk/swap space.This feature is also useful for supporting hot-plug memory on UML.
Concerns raised by Andrew Morton:
- "We have no plan for holepunching! If we _do_ have such a plan (or
might in the future) then what would the API look like? I think
sys_holepunch(fd, start, len), so we should start out with that."- Using madvise is very weird, because people will ask "why do I need to
mmap my file before I can stick a hole in it?"- None of the other madvise operations call into the filesystem in this
manner. A broad question is: is this capability an MM operation or a
filesytem operation? truncate, for example, is a filesystem operation
which sometimes has MM side-effects. madvise is an mm operation and with
this patch, it gains FS side-effects, only they're really, really
significant ones."Comments:
- Andrea suggested the fs operation too but then it's more efficient to
have it as a mm operation with fs side effects, because they don't
immediatly know fd and physical offset of the range. It's possible to
fixup in userland and to use the fs operation but it's more expensive,
the vmas are already in the kernel and we can use them.Short term plan & Future Direction:
- We seem to need this interface only for shmfs/tmpfs files in the short
term. We have to add hooks into the filesystem for correctness and
completeness. This is what this patch does.- In the future, plan is to support both fs and mmap apis also. This
also involves (other) filesystem specific functions to be implemented.- Current patch doesn't support VM_NONLINEAR - which can be addressed in
the future.Signed-off-by: Badari Pulavarty
Cc: Hugh Dickins
Cc: Andrea Arcangeli
Cc: Michael Kerrisk
Cc: Ulrich Drepper
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
04 Jan, 2006
1 commit
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Signed-off-by: Stephen Hemminger
Signed-off-by: David S. Miller
29 Nov, 2005
1 commit
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The attached patch implements a bunch of small changes to the FRV arch to
make it work again.It deals with the following problems:
(1) SEM_DEBUG should be SEMAPHORE_DEBUG.
(2) The argument list to pcibios_penalize_isa_irq() has changed.
(3) CONFIG_HIGHMEM can't be used directly in #if as it may not be defined.
(4) page->private is no longer directly accessible.
(5) linux/hardirq.h assumes asm/hardirq.h will include linux/irq.h
(6) The IDE MMIO access functions are given pointers, not integers, and so
get type casting errors.(7) __pa() is passed an explicit u64 type in drivers/char/mem.c, but that
can't be cast directly to a pointer on a 32-bit platform.(8) SEMAPHORE_DEBUG should not be contingent on WAITQUEUE_DEBUG as that no
longer exists.(9) PREEMPT_ACTIVE is too low a value.
Signed-off-by: David Howells
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
14 Nov, 2005
2 commits
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Introduce an atomic_inc_not_zero operation. Make this a special case of
atomic_add_unless because lockless pagecache actually wants
atomic_inc_not_negativeone due to its offset refcount.Signed-off-by: Nick Piggin
Cc: "Paul E. McKenney"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Introduce an atomic_cmpxchg operation.
Signed-off-by: Nick Piggin
Cc: "Paul E. McKenney"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
07 Nov, 2005
1 commit
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Fix more include file problems that surfaced since I submitted the previous
fix-missing-includes.patch. This should now allow not to include sched.h
from module.h, which is done by a followup patch.Signed-off-by: Tim Schmielau
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
31 Oct, 2005
2 commits
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__MUTEX_INITIALIZER() has no users, and equates to the more commonly used
DECLARE_MUTEX(), thus making it pretty much redundant. Remove it for good.Signed-off-by: Arthur Othieno
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch removes page_pte_prot and page_pte macros from all
architectures. Some architectures define both, some only page_pte (broken)
and others none. These macros are not used anywhere.page_pte_prot(page, prot) is identical to mk_pte(page, prot) and
page_pte(page) is identical to page_pte_prot(page, __pgprot(0)).* The following architectures define both page_pte_prot and page_pte
arm, arm26, ia64, sh64, sparc, sparc64
* The following architectures define only page_pte (broken)
frv, i386, m32r, mips, sh, x86-64
* All other architectures define neither
Signed-off-by: Tejun Heo
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
28 Oct, 2005
1 commit
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Signed-off-by: Al Viro
Signed-off-by: Linus Torvalds
22 Sep, 2005
1 commit
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As recently done by Russell King for ARM, commit
4732efbeb997189d9f9b04708dc26bf8613ed721 introduces a generic asm/futex.h copied
along most arches, which includes a "-ENOSYS support" to be changed if needed.
However, it includes an unused var (taken from the "real" version) which GCC
warns about.Remove it from all arches having that file version (i.e. same GIT id).
$ git-diff-tree -r HEAD
and
$ git-ls-tree -r HEAD include/|grep 9feff4ce1424bc390608326240be369eb13aa648may be more interesting than looking at the patch itself, to make sure I've
just copied the arm header to all other archs having the original dummy version
of this file.Cc: Jakub Jelinek
Signed-off-by: Paolo 'Blaisorblade' Giarrusso
Signed-off-by: Linus Torvalds
13 Sep, 2005
1 commit
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As written in Documentation/feature-removal-schedule.txt, remove the
io_remap_page_range() kernel API.Signed-off-by: Randy Dunlap
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
08 Sep, 2005
8 commits
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This patch gathers all the struct flock64 definitions (and the operations),
puts them under !CONFIG_64BIT and cleans up the arch files.Signed-off-by: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch just gathers together all the struct flock definitions except
xtensa into asm-generic/fcntl.h.Signed-off-by: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch puts the most popular of each fcntl operation/flag into
asm-generic/fcntl.h and cleans up the arch files.Signed-off-by: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch puts the most popular of each open flag into asm-generic/fcntl.h
and cleans up the arch files.Signed-off-by: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This set of patches creates asm-generic/fcntl.h and consolidates as much as
possible from the asm-*/fcntl.h files into it.This patch just gathers all the identical bits of the asm-*/fcntl.h files into
asm-generic/fcntl.h.Signed-off-by: Stephen Rothwell
Signed-off-by: Yoichi Yuasa
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Remove the deprecated (and unused) verify_area() from various uaccess.h
headers.Signed-off-by: Jesper Juhl
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The size of auxiliary vector is fixed at 42 in linux/sched.h. But it isn't
very obvious when looking at linux/elf.h. This patch adds AT_VECTOR_SIZE
so that we can change it if necessary when a new vector is added.Because of include file ordering problems, doing this necessitated the
extraction of the AT_* symbols into a standalone header file.Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
ATM pthread_cond_signal is unnecessarily slow, because it wakes one waiter
(which at least on UP usually means an immediate context switch to one of
the waiter threads). This waiter wakes up and after a few instructions it
attempts to acquire the cv internal lock, but that lock is still held by
the thread calling pthread_cond_signal. So it goes to sleep and eventually
the signalling thread is scheduled in, unlocks the internal lock and wakes
the waiter again.Now, before 2003-09-21 NPTL was using FUTEX_REQUEUE in pthread_cond_signal
to avoid this performance issue, but it was removed when locks were
redesigned to the 3 state scheme (unlocked, locked uncontended, locked
contended).Following scenario shows why simply using FUTEX_REQUEUE in
pthread_cond_signal together with using lll_mutex_unlock_force in place of
lll_mutex_unlock is not enough and probably why it has been disabled at
that time:The number is value in cv->__data.__lock.
thr1 thr2 thr3
0 pthread_cond_wait
1 lll_mutex_lock (cv->__data.__lock)
0 lll_mutex_unlock (cv->__data.__lock)
0 lll_futex_wait (&cv->__data.__futex, futexval)
0 pthread_cond_signal
1 lll_mutex_lock (cv->__data.__lock)
1 pthread_cond_signal
2 lll_mutex_lock (cv->__data.__lock)
2 lll_futex_wait (&cv->__data.__lock, 2)
2 lll_futex_requeue (&cv->__data.__futex, 0, 1, &cv->__data.__lock)
# FUTEX_REQUEUE, not FUTEX_CMP_REQUEUE
2 lll_mutex_unlock_force (cv->__data.__lock)
0 cv->__data.__lock = 0
0 lll_futex_wake (&cv->__data.__lock, 1)
1 lll_mutex_lock (cv->__data.__lock)
0 lll_mutex_unlock (cv->__data.__lock)
# Here, lll_mutex_unlock doesn't know there are threads waiting
# on the internal cv's lockNow, I believe it is possible to use FUTEX_REQUEUE in pthread_cond_signal,
but it will cost us not one, but 2 extra syscalls and, what's worse, one of
these extra syscalls will be done for every single waiting loop in
pthread_cond_*wait.We would need to use lll_mutex_unlock_force in pthread_cond_signal after
requeue and lll_mutex_cond_lock in pthread_cond_*wait after lll_futex_wait.Another alternative is to do the unlocking pthread_cond_signal needs to do
(the lock can't be unlocked before lll_futex_wake, as that is racy) in the
kernel.I have implemented both variants, futex-requeue-glibc.patch is the first
one and futex-wake_op{,-glibc}.patch is the unlocking inside of the kernel.
The kernel interface allows userland to specify how exactly an unlocking
operation should look like (some atomic arithmetic operation with optional
constant argument and comparison of the previous futex value with another
constant).It has been implemented just for ppc*, x86_64 and i?86, for other
architectures I'm including just a stub header which can be used as a
starting point by maintainers to write support for their arches and ATM
will just return -ENOSYS for FUTEX_WAKE_OP. The requeue patch has been
(lightly) tested just on x86_64, the wake_op patch on ppc64 kernel running
32-bit and 64-bit NPTL and x86_64 kernel running 32-bit and 64-bit NPTL.With the following benchmark on UP x86-64 I get:
for i in nptl-orig nptl-requeue nptl-wake_op; do echo time elf/ld.so --library-path .:$i /tmp/bench; \
for j in 1 2; do echo ( time elf/ld.so --library-path .:$i /tmp/bench ) 2>&1; done; done
time elf/ld.so --library-path .:nptl-orig /tmp/bench
real 0m0.655s user 0m0.253s sys 0m0.403s
real 0m0.657s user 0m0.269s sys 0m0.388s
time elf/ld.so --library-path .:nptl-requeue /tmp/bench
real 0m0.496s user 0m0.225s sys 0m0.271s
real 0m0.531s user 0m0.242s sys 0m0.288s
time elf/ld.so --library-path .:nptl-wake_op /tmp/bench
real 0m0.380s user 0m0.176s sys 0m0.204s
real 0m0.382s user 0m0.175s sys 0m0.207sThe benchmark is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00001.txt
Older futex-requeue-glibc.patch version is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00002.txt
Older futex-wake_op-glibc.patch version is at:
http://sourceware.org/ml/libc-alpha/2005-03/txt00003.txt
Will post a new version (just x86-64 fixes so that the patch
applies against pthread_cond_signal.S) to libc-hacker ml soon.Attached is the kernel FUTEX_WAKE_OP patch as well as a simple-minded
testcase that will not test the atomicity of the operation, but at least
check if the threads that should have been woken up are woken up and
whether the arithmetic operation in the kernel gave the expected results.Acked-by: Ingo Molnar
Cc: Ulrich Drepper
Cc: Jamie Lokier
Cc: Rusty Russell
Signed-off-by: Yoichi Yuasa
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
05 Sep, 2005
2 commits
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This is used only in slab.c and each architecture gets to define whcih
underlying type is to be used.Seems a bit silly - move it to slab.c and use the same type for all
architectures: unsigned int.Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Someone mentioned that almost all the architectures used basically the same
implementation of get_order. This patch consolidates them into
asm-generic/page.h and includes that in the appropriate places. The
exceptions are ia64 and ppc which have their own (presumably optimised)
versions.Signed-off-by: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
30 Aug, 2005
1 commit
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Allows overriding of sysctl_{wmem,rmrm}_max
Signed-off-by: Patrick McHardy
Signed-off-by: David S. Miller
27 Jul, 2005
1 commit
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When the kernel is working well and we want to restart cleanly
kernel_restart is the function to use. But in many instances
the kernel wants to reboot when thing are expected to be working
very badly such as from panic or a software watchdog handler.This patch adds the function emergency_restart() so that
callers can be clear what semantics they expect when calling
restart. emergency_restart() is expected to be callable
from interrupt context and possibly reliable in even more
trying circumstances.This is an initial generic implementation for all architectures.
Signed-off-by: Eric W. Biederman
Signed-off-by: Linus Torvalds
28 Jun, 2005
2 commits
-
With CONFIG_PCI=n:
In file included from include/linux/pci.h:917,
from lib/iomap.c:6:
include/asm/pci.h:104: warning: `enum pci_dma_burst_strategy' declared inside parameter list
include/asm/pci.h:104: warning: its scope is only this definition or declaration, which is probably not what you want.
include/asm/pci.h: In function `pci_dma_burst_advice':
include/asm/pci.h:106: dereferencing pointer to incomplete type
include/asm/pci.h:106: `PCI_DMA_BURST_INFINITY' undeclared (first use in this function)
include/asm/pci.h:106: (Each undeclared identifier is reported only once
include/asm/pci.h:106: for each function it appears in.)
make[1]: *** [lib/iomap.o] Error 1Signed-off-by: Andrew Morton
Signed-off-by: Greg Kroah-Hartman -
After seeing, at best, "guesses" as to the following kind
of information in several drivers, I decided that we really
need a way for platforms to specifically give advice in this
area for what works best with their PCI controller implementation.Basically, this new interface gives DMA bursting advice on
PCI. There are three forms of the advice:1) Burst as much as possible, it is not necessary to end bursts
on some particular boundary for best performance.2) Burst on some byte count multiple. A DMA burst to some multiple of
number of bytes may be done, but it is important to end the burst
on an exact multiple for best performance.The best example of this I am aware of are the PPC64 PCI
controllers, where if you end a burst mid-cacheline then
chip has to refetch the data and the IOMMU translations
which hurts performance a lot.3) Burst on a single byte count multiple. Bursts shall end
exactly on the next multiple boundary for best performance.Sparc64 and Alpha's PCI controllers operate this way. They
disconnect any device which tries to burst across a cacheline
boundary.Actually, newer sparc64 PCI controllers do not have this behavior.
That is why the "pdev" is passed into the interface, so I can
add code later to check which PCI controller the system is using
and give advice accordingly.Signed-off-by: David S. Miller
Signed-off-by: Greg Kroah-Hartman
