Cleanup: setting an outstanding error on a mapping was open coded too many
times. Factor it out in mapping_set_error().
Signed-off-by: Guillaume Chazarain <guichaz@yahoo.fr>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The ever-vigilant users of linode.com noticed that an idle 2.6 UML has a
persistent load average of ~.4.
It turns out that because the UML timer handler processed softirqs before
actually delivering the tick, the tick was counted in the context of the idle
thread about half the time.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
hostfs needed some style goodness.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch allows hostfs_setattr() to work on unlinked open files by calling
set_attr() (the userspace part) with the inode's fd.
Without this, applications that depend on doing attribute changes to unlinked
open files will fail.
It works by using the fd versions instead of the path ones (for example
fchmod() instead of chmod(), fchown() instead of chown()) when an fd is
available.
Signed-off-by: Alberto Bertogli <albertito@gmail.com>
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use SLAB_PANIC and delete duplicated panic().
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Ian Molton <spyro@f2s.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch is add white list into modpost.c for some functions and
ia64's section to fix section mismatchs.
sparse_index_alloc() and zone_wait_table_init() calls bootmem allocator
at boot time, and kmalloc/vmalloc at hotplug time. If config
memory hotplug is on, there are references of bootmem allocater(init text)
from them (normal text). This is cause of section mismatch.
Bootmem is called by many functions and it must be
used only at boot time. I think __init of them should keep for
section mismatch check. So, I would like to register sparse_index_alloc()
and zone_wait_table_init() into white list.
In addition, ia64's .machvec section is function table of some platform
dependent code. It is mixture of .init.text and normal text. These
reference of __init functions are valid too.
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is to fix many section mismatches of code related to memory hotplug.
I checked compile with memory hotplug on/off on ia64 and x86-64 box.
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are two problems with the existing redzone implementation.
Firstly, it's causing misalignment of structures which contain a 64-bit
integer, such as netfilter's 'struct ipt_entry' -- causing netfilter
modules to fail to load because of the misalignment. (In particular, the
first check in
net/ipv4/netfilter/ip_tables.c::check_entry_size_and_hooks())
On ppc32 and sparc32, amongst others, __alignof__(uint64_t) == 8.
With slab debugging, we use 32-bit redzones. And allocated slab objects
aren't sufficiently aligned to hold a structure containing a uint64_t.
By _just_ setting ARCH_KMALLOC_MINALIGN to __alignof__(u64) we'd disable
redzone checks on those architectures. By using 64-bit redzones we avoid that
loss of debugging, and also fix the other problem while we're at it.
When investigating this, I noticed that on 64-bit platforms we're using a
32-bit value of RED_ACTIVE/RED_INACTIVE in the 64-bit memory location set
aside for the redzone. Which means that the four bytes immediately before
or after the allocated object at 0x00,0x00,0x00,0x00 for LE and BE
machines, respectively. Which is probably not the most useful choice of
poison value.
One way to fix both of those at once is just to switch to 64-bit
redzones in all cases.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'server-cluster-locking-api' of git://linux-nfs.org/~bfields/linux:
gfs2: nfs lock support for gfs2
lockd: add code to handle deferred lock requests
lockd: always preallocate block in nlmsvc_lock()
lockd: handle test_lock deferrals
lockd: pass cookie in nlmsvc_testlock
lockd: handle fl_grant callbacks
lockd: save lock state on deferral
locks: add fl_grant callback for asynchronous lock return
nfsd4: Convert NFSv4 to new lock interface
locks: add lock cancel command
locks: allow {vfs,posix}_lock_file to return conflicting lock
locks: factor out generic/filesystem switch from setlock code
locks: factor out generic/filesystem switch from test_lock
locks: give posix_test_lock same interface as ->lock
locks: make ->lock release private data before returning in GETLK case
locks: create posix-to-flock helper functions
locks: trivial removal of unnecessary parentheses
The newly merged SLUB allocator patches had been generated before the
removal of "struct subsystem", and ended up applying fine, but wouldn't
build based on the current tree as a result.
Fix up that merge error - not that SLUB is likely really ready for
showtime yet, but at least I can fix the trivial stuff.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'drm-patches' of master.kernel.org:/pub/scm/linux/kernel/git/airlied/drm-2.6:
drm/i915: Add 965GM pci id update
drm: just use io_remap_pfn_range on all archs..
drm: fix DRM_CONSISTENT mapping
drm: fix up mmap locking in preparation for ttm changes
drm: fix driver deadlock with AIGLX and reclaim_buffers_locked
drm: fix warning in drm_fops.c
drm: allow for more generic drm ioctls
drm: fix alpha domain handling
via: fix CX700 pci id
drm: make drm_io_prot static.
drm: remove via_mm.h
drm: add missing NULL assignment
drm/radeon: Fix u32 overflows when determining AGP base address in card space.
drm: port over use_vmalloc code from git hashtab
drm: fix crash with fops lock and fixup sarea/page size locking
drm: bring bufs code from git tree.
drm: move protection stuff into separate function
drm: Use ARRAY_SIZE macro when appropriate
drm: update README.drm (bugzilla #7933)
drm: remove unused exports
* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
[NET]: rfkill: add support for input key to control wireless radio
[NET] net/core: Fix error handling
[TG3]: Update version and reldate.
[TG3]: Eliminate spurious interrupts.
[TG3]: Add ASPM workaround.
[Bluetooth] Correct SCO buffer for another Broadcom based dongle
[Bluetooth] Add support for Targus ACB10US USB dongle
[Bluetooth] Disconnect L2CAP connection after last RFCOMM DLC
[Bluetooth] Check that device is in rfcomm_dev_list before deleting
[Bluetooth] Use in-kernel sockets API
[Bluetooth] Attach host adapters to the Bluetooth bus
[Bluetooth] Fix L2CAP and HCI setsockopt() information leaks
* master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6:
[SERIAL] sunsu: Fix section mismatch warnings.
[SPARC64]: pgtable_cache_init() should be __init.
[SPARC64]: Fix section mismatch warnings in arch/sparc64/kernel/prom.c
[SPARC64]: Fix section mismatch warnings in arch/sparc64/kernel/pci.c
[SPARC64]: Fix section mismatch warnings in arch/sparc64/kernel/console.c
[MM]: sparse_init() should be __init.
[SPARC64]: Update defconfig.
[VIDEO]: Add Sun XVR-2500 framebuffer driver.
[VIDEO]: Add Sun XVR-500 framebuffer driver.
[SPARC64]: SUN4U PCI-E controller support.
[SPARC]: Fix comment typo in smp4m_blackbox_current().
[SCSI] SUNESP: sun_esp.c needs linux/delay.h
Fix up conflict in arch/sparc64/mm/init.c manually due to removal of
pgtable_cache_init() through the -mm patches (even though that patch was
also by David ;)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband:
IPoIB: Convert to NAPI
IB: Return "maybe missed event" hint from ib_req_notify_cq()
IB: Add CQ comp_vector support
IB/ipath: Fix a race condition when generating ACKs
IB/ipath: Fix two more spin lock problems
IB/fmr_pool: Add prefix to all printks
IB/srp: Set proc_name
IB/srp: Add orig_dgid sysfs attribute to scsi_host
IPoIB/cm: Don't crash if remote side uses one QP for both directions
RDMA/cxgb3: Support for new abort logic
RDMA/cxgb3: Initialize cpu_idx field in cpl_close_listserv_req message
RDMA/cxgb3: Fail qp creation if the requested max_inline is too large
RDMA/cxgb3: Fix TERM codes
IPoIB/cm: Fix error handling in ipoib_cm_dev_open()
IB/ipath: Don't corrupt pending mmap list when unmapped objects are freed
IB/mthca: Work around kernel QP starvation
IB/ipath: Don't put QP in timeout queue if waiting to send
IB/ipath: Don't call spin_lock_irq() from interrupt context
Commit a836f5856a removes the shutdown
member of the bitbang structure, breaking the build of spi_s3c24xx.c.
Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rename config for TANBAC TB0219 GPIO support to something more appropriate.
Fixes this:
drivers/char/Kconfig:906:warning: type of 'TANBAC_TB0219' redefined from 'boolean' to 'tristate'
drivers/char/Kconfig:907:warning: choice values currently only support a single
prompt
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As seen on powerpc-cell et al:
CC [M] drivers/usb/host/ehci-hcd.o
In file included from drivers/usb/host/ehci-hcd.c:941:
drivers/usb/host/ehci-ps3.c:79: error: conflicting types for 'dev_dbg'
include/linux/device.h:576: error: previous definition of 'dev_dbg' was here
make[4]: *** [drivers/usb/host/ehci-hcd.o] Error 1
CC [M] drivers/usb/host/ohci-hcd.o
In file included from drivers/usb/host/ohci-hcd.c:921:
drivers/usb/host/ohci-ps3.c:83: error: conflicting types for 'dev_dbg'
include/linux/device.h:576: error: previous definition of 'dev_dbg' was here
dev_dbg() will check format string for you in dummy case also, so remove
buggers.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greg KH <greg@kroah.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Geoff Levand <geoffrey.levand@am.sony.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The last zlib_inflate update broke certain corner cases for ppp_deflate
decompression handling. This patch fixes some logic to make things work
properly again. Users other than ppp_deflate (the only Z_PACKET_FLUSH
user) should be unaffected.
Fixes bug 8405 (confirmed by Stefan)
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Cc: Stefan Wenk <stefan.wenk@gmx.at>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
alpha:
drivers/media/video/cx88/cx88-video.c: In function 'cx8800_initdev':
drivers/media/video/cx88/cx88-video.c:1782: error: 'DMA_32BIT_MASK' undeclared (first use in this function)
drivers/media/video/cx88/cx88-video.c:1782: error: (Each undeclared identifier is reported only once
drivers/media/video/cx88/cx88-video.c:1782: error: for each function it appears in.)
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
strlcpy already accounts for the trailing zero in its length
computation, so there is no need to substract one to the buffer size.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert an arch that does not currently implement sub-jiffy timekeeping to
use the generic timekeeping code.
v850 looks like it has some intent to implement sub-jiffy timekeeping, so
it may not yet be appropriate to try to convert, but I figured I'd get the
maintainer's input and submit the patch for comment.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Declare strlcpy and strlcat more correctly.
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With the current timekeeping, !CONFIG_UML_REAL_TIME_CLOCK has
inconsistent behavior. Previously, gettimeofday could be (and was)
isolated from the clock ticking. Now, it's not, so when
CONFIG_UML_REAL_TIME_CLOCK is disabled, gettimeofday must progress in
lockstep with the clock, making it fully virtual.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It turns out that the message complaining about a lack of tmpfs space
on the host can be misunderstood as referring to the UML.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When doing a full address space flush, only look at areas covered by a VMA.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
More trimming of the page fault path.
Permissions are passed around in a single int rather than one bit per
int. The permission values are copied from libc so that they can be
passed to mmap and mprotect without any further conversion.
The register sets used by do_syscall_stub and copy_context_skas0 are
initialized once, at boot time, rather than once per call.
wait_stub_done checks whether it is getting the signals it expects by
comparing the wait status to a mask containing bits for the signals of
interest rather than comparing individually to the signal numbers. It
also has one check for a wait failure instead of two. The caller is
expected to do the initial continue of the stub. This gets rid of an
argument and some logic. The fname argument is gone, as that can be
had from a stack trace.
user_signal() is collapsed into userspace() as it is basically one or
two lines of code afterwards.
The physical memory remapping stuff is gone, as it is unused.
flush_tlb_page is inlined.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I missed removing another piece of debugging in an earlier patch.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Give the page fault code a specialized path. There is only one page to look
at, so there's no point in going into the general page table walking code.
There's only going to be one host operation, so there are no opportunities for
merging. So, we go straight to the pte we want, figure out what needs doing,
and do it.
While I was in here, I fixed the wart where the address passed to unmap was a
void *, but an unsigned long to map and protect.
This gives me just under 10% on a kernel build.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Allow deadlocks to be avoided in the AIO code by setting the pipe to the I/O
thread non-blocking.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rename os_{read_write}_file_k back to os_{read_write}_file, delete
the originals and their bogus infrastructure, and fix all the callers.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I accidentally left the remnants of some debugging in an earlier patch.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Formatting fixes ahead of renaming os_{read_write}_file_k to
os_{read_write}_file and fixing all the callers.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert all remaining os_{read_write}_file users to use the simple
{read,write} wrappers, os_{read_write}_file_k.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Code running on the initial UML stack can't receive or process signals since
current must be valid when IRQs are handled, and there is no current for this
stack.
So, instead of using UML_LONGJMP and UML_SETJMP, which are careful to save and
restore signal state, and, as a side-effect, handle any deferred signals,
start_idle_thread must use the bare equivalents, which don't do anything with
signals.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dump core after a panic. This will provide better debugging information than
is currently available.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sanitise gfp flags; it actually is an atomic context, so drop the
GFP_KERNEL part.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Instead of writing entire structures between UML and the I/O thread, we send
pointers. This cuts down on the amount of data being copied and possibly
allows more requests to be pending between the two.
This requires that the requests be kmalloced and freed instead of living on
the stack.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Send as many I/O requests to the I/O thread as possible, even though it will
still only handle one at a time. This provides an opportunity to reduce
latency by starting one request before the previous one has been finished in
the driver.
Request handling is somewhat modernized by requesting sg pieces of a request
and handling them separately, finishing off the entire request after all the
pieces are done.
When a request queue stalls, normally because its pipe to the I/O thread is
full, it is put on the restart list. This list is processed by starting up
the queues on it whenever there is some indication that progress might be
possible again. Currently, this happens in the driver interrupt routine.
Some requests have been finished, so there is likely to be room in the pipe
again.
This almost doubles throughput when copying data between devices, but made no
noticable difference on anything else I tried.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch converts calls in the os layer to os_{read,write}_file to calls
directly to libc read() and write() where it is clear that the I/O buffer is
in the kernel.
We can do that here instead of calling os_{read,write}_file_k since we are in
libc code and can call libc directly.
With the change in the calls, error handling needs to be changed to refer to
errno directly rather than the return value of the call.
CATCH_EINTR wrappers were also added where needed.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch lays some groundwork for the next one, which converts calls to
os_{read,write}_file into {read,write}, by doing some tidying in the affected
areas.
do_not_aio gets restructured to make the final result a bit cleaner.
There are also whitespace and other formatting fixes, fixes in error messages,
and a typo fix.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch starts the removal of a very old, very broken piece of code. This
stems from the problem of passing a userspace buffer into read() or write() on
the host. If that buffer had not yet been faulted in, read and write will
return -EFAULT.
To avoid this problem, the solution was to fault the buffer in before the
system call by touching the pages that hold the buffer by doing a copy-user of
a byte to each page. This is obviously bogus, but it does usually work, in tt
mode, since the kernel and process are in the same address space and userspace
addresses can be accessed directly in the kernel.
In skas mode, where the kernel and process are in separate address spaces, it
is completely bogus because the userspace address, which is invalid in the
kernel, is passed into the system call instead of the corresponding physical
address, which would be valid. Here, it appears that this code, on every host
read() or write(), tries to fault in a random process page. This doesn't seem
to cause any correctness problems, but there is a performance impact. This
patch, and the ones following, result in a 10-15% performance gain on a kernel
build.
This code can't be immediately tossed out because when it is, you can't log
in. Apparently, there is some code in the console driver which depends on
this somehow.
However, we can start removing it by switching the code which does I/O using
kernel addresses to using plain read() and write(). This patch introduces
os_read_file_k and os_write_file_k for use with kernel buffers and converts
all call locations which use obvious kernel buffers to use them. These
include I/O using buffers which are local variables which are on the stack or
kmalloc-ed. Later patches will handle the less obvious cases, followed by a
mass conversion back to the original interface.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It turns out that essentially none of the x86_64 bugs.c is needed. So, we can
delete most of it.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
