Commit Graph

116 Commits

Author SHA1 Message Date
David Woodhouse
62c4f0a2d5 Don't include linux/config.h from anywhere else in include/
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2006-04-26 12:56:16 +01:00
Kyle McMartin
1b52d7c221 [PARISC] Make ioremap default to _nocache
Since it is way more work to change most drivers to comply with parisc, take
the easy way out and make ioremap _NO_CACHE by default. This is in line with
what powerpc does.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-04-21 22:20:35 +00:00
Kyle McMartin
6ca773cf8b [PARISC] Add new entries to the syscall table
Most are easy, but sync_file_range needed special handling when entering
through the 32-bit syscall table.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-04-21 22:20:35 +00:00
Helge Deller
2fd8303816 [PARISC] Further work for multiple page sizes
More work towards supporing multiple page sizes on 64-bit. Convert
some assumptions that 64bit uses 3 level page tables into testing
PT_NLEVELS. Also some BUG() to BUG_ON() conversions and some cleanups
to assembler.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-04-21 22:20:34 +00:00
Yasunori Goto
c80d79d746 [PATCH] Configurable NODES_SHIFT
Current implementations define NODES_SHIFT in include/asm-xxx/numnodes.h for
each arch.  Its definition is sometimes configurable.  Indeed, ia64 defines 5
NODES_SHIFT values in the current git tree.  But it looks a bit messy.

SGI-SN2(ia64) system requires 1024 nodes, and the number of nodes already has
been changeable by config.  Suitable node's number may be changed in the
future even if it is other architecture.  So, I wrote configurable node's
number.

This patch set defines just default value for each arch which needs multi
nodes except ia64.  But, it is easy to change to configurable if necessary.

On ia64 the number of nodes can be already configured in generic ia64 and SN2
config.  But, NODES_SHIFT is defined for DIG64 and HP'S machine too.  So, I
changed it so that all platforms can be configured via CONFIG_NODES_SHIFT.  It
would be simpler.

See also: http://marc.theaimsgroup.com/?l=linux-kernel&m=114358010523896&w=2

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jack Steiner <steiner@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-11 06:18:39 -07:00
Kyle McMartin
4da9f131a7 [PARISC] Add atomic_sub_and_test
Define atomic_sub_and_test to fix build failures.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:59 +00:00
Kyle McMartin
2746ae14fe [PARISC] Make local_t use atomic_long_t
As done in asm-generic/local.h in mainline. Otherwise local_t was 32-bit
even on a 64-bit kernel.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:56 +00:00
Kyle McMartin
50a34dbd61 [PARISC] Add PREEMPT support
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:54 +00:00
Kyle McMartin
bc8846c522 [PARISC] More useful readwrite lock helpers
spinlock.c needs _can_lock helpers. Rewrite _is_locked helpers to be
_can_lock helpers.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:53 +00:00
Helge Deller
10267cdd0c [PARISC] Fixup CONFIG_EISA a bit
Fix up some ISA/EISA stuff.

(Note: isa_ accessors have been removed from asm/io.h)

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:52 +00:00
Helge Deller
a41d3862df [PARISC] Remove obsolete CONFIG_DEBUG_IOREMAP
Remove CONFIG_DEBUG_IOREMAP, it's now obsolete and won't work anyway.
Remove it from lib/KConfig since it was only available on parisc.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:50 +00:00
Helge Deller
29ef829532 [PARISC] Enable ioremap functionality unconditionally
Enable CONFIG_HPPA_IOREMAP by default and remove all now unnecessary code.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:48 +00:00
Helge Deller
b8ce0aadcd [PARISC] Add CONFIG_HPPA_IOREMAP to conditionally enable ioremap
Instead of making it a #define in asm/io.h, allow user to select
to turn on IOREMAP from the config menu.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:46 +00:00
Helge Deller
b31059f763 [PARISC] Add STRICT_MM_TYPECHECKS
Add STRICT_MM_TYPECHECKS to page.h as other architectures do.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:45 +00:00
James Bottomley
ba57583396 [PARISC] Add parisc implementation of flush_kernel_dcache_page()
We need to do a little renaming of our original syntax because
of the difference in arguments.

Signed-off-by: James Bottomley <jejb@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:44 +00:00
James Bottomley
ab43227c8a [PARISC] Add parisc implementation of flush_anon_page()
This should now allow SG_IO and fuse to function correctly on our
platform.

Signed-off-by: James Bottomley <jejb@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:43 +00:00
Thibaut VARENE
a81dd18eb9 [PARISC] Clarify pdc_stable license terms
pdc_stable.c is explicitly licensed under GPL version 2.

Signed-off-by: Thibaut VARENE <varenet@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-03-30 17:48:41 +00:00
Alexey Dobriyan
7f927fcc2f [PATCH] Typo fixes
Fix a lot of typos.  Eyeballed by jmc@ in OpenBSD.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 09:16:08 -08:00
Ingo Molnar
213b63b76a [PATCH] parisc: add ptr_to_compat()
Add ptr_to_compat() to parisc - needed by the new robust futex code.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Grant Grundler <iod00d@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:48 -08:00
KAMEZAWA Hiroyuki
0d833b4109 [PATCH] unify pfn_to_page: parisc pfn_to_page
PARISC can use generic funcs.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27 08:44:46 -08:00
Akinobu Mita
59e18a2e1c [PATCH] bitops: parisc: use generic bitops
- remove __{,test_and_}{set,clear,change}_bit() and test_bit()
- remove ffz()
- remove generic_fls64()
- remove generic_hweight{32,16,8}()
- remove generic_hweight64()
- remove sched_find_first_bit()
- remove find_{next,first}{,_zero}_bit()
- remove ext2_{set,clear,test,find_first_zero,find_next_zero}_bit()

Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:57:14 -08:00
Akinobu Mita
3156054b02 [PATCH] bitops: parisc: add ()-pair in __ffz() macro
Noticed by Michael Tokarev

add missing ()-pair in __ffz() macro for parisc

Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:57:10 -08:00
Davide Libenzi
f348d70a32 [PATCH] POLLRDHUP/EPOLLRDHUP handling for half-closed devices notifications
Implement the half-closed devices notifiation, by adding a new POLLRDHUP
(and its alias EPOLLRDHUP) bit to the existing poll/select sets.  Since the
existing POLLHUP handling, that does not report correctly half-closed
devices, was feared to be changed, this implementation leaves the current
POLLHUP reporting unchanged and simply add a new bit that is set in the few
places where it makes sense.  The same thing was discussed and conceptually
agreed quite some time ago:

http://lkml.org/lkml/2003/7/12/116

Since this new event bit is added to the existing Linux poll infrastruture,
even the existing poll/select system calls will be able to use it.  As far
as the existing POLLHUP handling, the patch leaves it as is.  The
pollrdhup-2.6.16.rc5-0.10.diff defines the POLLRDHUP for all the existing
archs and sets the bit in the six relevant files.  The other attached diff
is the simple change required to sys/epoll.h to add the EPOLLRDHUP
definition.

There is "a stupid program" to test POLLRDHUP delivery here:

 http://www.xmailserver.org/pollrdhup-test.c

It tests poll(2), but since the delivery is same epoll(2) will work equally.

Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25 08:22:56 -08:00
Al Viro
57f3ebccaa [PATCH] remove ISA legacy functions: remove the helpers
unused isa_...() helpers removed.

Adrian Bunk:
The asm-sh part was rediffed due to unrelated changes.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24 07:33:19 -08:00
Kyle McMartin
804f1594cc [PATCH] Move read_mostly definition to asm/cache.h
Seems like needless clutter having a bunch of #if defined(CONFIG_$ARCH) in
include/linux/cache.h.  Move the per architecture section definition to
asm/cache.h, and keep the if-not-defined dummy case in linux/cache.h to
catch architectures which don't implement the section.

Verified that symbols still go in .data.read_mostly on parisc,
and the compile doesn't break.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:10 -08:00
Michael S. Tsirkin
5f6164f309 [PATCH] add asm-generic/mman.h
Make new MADV_REMOVE, MADV_DONTFORK, MADV_DOFORK consistent across all
arches.  The idea is to make it possible to use them portably even before
distros include them in libc headers.

Move common flags to asm-generic/mman.h

Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-15 15:32:22 -08:00
Michael S. Tsirkin
f822566165 [PATCH] madvise MADV_DONTFORK/MADV_DOFORK
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 <mst@mellanox.co.il>
Acked-by: Hugh Dickins <hugh@veritas.com>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-14 16:09:34 -08:00
Kyle McMartin
68ee3eb829 [PARISC] New syscalls (inotify, *at, pselect6/ppoll, migrate_pages)
Wire up some new syscalls that have been merged upstream,
  o inotify
  o openat et al
  o pselect6/ppoll
  o migrate_pages

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-01-30 00:53:14 -05:00
Kyle McMartin
f671c45df2 [PARISC] Arch-specific compat signals
Add enough arch-specific compat signals code to enable parisc64
to compile and boot out of the mainline tree. There are likely still
many dragons here, but this is a start to squashing the last
big difference between the mainline tree and the parisc-linux tree.
The remaining bugs can be squashed as they come up.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-01-22 20:57:42 -05:00
Helge Deller
1bcdd85482 [PARISC] Add CONFIG_DEBUG_RODATA to protect read-only data
Add the parisc version of the "mark rodata section read only" patches.
Based on code from and Signed-off-by Arjan van de Ven
<arjan@infradead.org>, Ingo Molnar <mingo@elte.hu>, Andi Kleen <ak@muc.de>,
Andrew Morton <akpm@osdl.org>, Linus Torvalds <torvalds@osdl.org>.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-01-22 20:26:54 -05:00
Kyle McMartin
2e13b31e5b [PARISC] atomic64 support
Implement atomic64_t so atomic_long_t works on parisc. Also
clean up some of the coding style in atomic.h, and make sure
ATOMIC_INIT is cast properly.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-01-22 20:26:44 -05:00
Helge Deller
c475eea292 [PARISC] Drop unused do_check_pgt_cache()
Drop the unused do_check_pgt_cache routine from mm/init.c and its
prototype in asm/pgalloc.h

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-01-22 20:26:37 -05:00
Grant Grundler
2c9aadabf4 [PARISC] Remove unnecessary extern declarations from asm/pci.h
Remove two unnecessary extern declarations from asm/pci.h.
They collide with what gcc4.0 assumed was static (and should be static).
Found by Joel Soete.

Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-01-22 20:26:34 -05:00
Helge Deller
cb6fc18e9c [PARISC] Use kzalloc and other janitor-style cleanups
Helge,
  o Convert a bunch of kmalloc/memset uses to kzalloc.
  o pci.c: Add some __read_mostly annotations.
  o pci.c: Move constant pci_post_reset_delay to asm/pci.h
  o grfioctl.h: Add A4450A to comment of CRT_ID_VISUALIZE_EG.
  o Add some consts to perf.c/perf_images.h

Matthew,
  o sticore.c: Add some consts to suppress compile warnings.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Matthew Wilcox <willy@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-01-22 20:26:31 -05:00
Al Viro
f5a61d0c13 [PATCH] death of get_thread_info/put_thread_info
{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 <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-12 09:08:59 -08:00
Ingo Molnar
4dc7a0bbeb [PATCH] sched: add cacheflush() asm
Add per-arch sched_cacheflush() which is a write-back cacheflush used by
the migration-cost calibration code at bootup time.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-12 09:08:49 -08:00
Alexey Dobriyan
02d79800a2 [PARISC] Use C99 initializers in asm-parisc/processor.h
Cleanup asm-parisc/processor.h to use C99 initializers in
INIT_THREAD().

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-01-10 21:52:45 -05:00
Grant Grundler
9b9ff2e16a [PARISC] Make PCI_HOST_ADDR and PCI_BUS_ADDR symmetrical
Change to asm-parisc/pci.h makes the define of PCI_HOST_ADDR symmetrical
with PCI_BUS_ADDR. Also add a comment about PA_VIEW and LMMIO/ELMMIO/GMMIO.

Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-01-10 21:52:30 -05:00
Alexey Dobriyan
110957f0e5 [PARISC] Add __iomem to __raw_check_addr()
Add __iomem to __raw_check_addr(), which nukes ~13809 sparse
warnings on allmodconfig.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-01-10 21:51:57 -05:00
Helge Deller
e8b736c860 [PARISC] Add some defines for HugeTLB pages
Define some constants for HugeTLB pages, not that parisc-linux supports
it yet.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-01-10 21:51:51 -05:00
Matthew Wilcox
1b2425e3c7 [PARISC] Make local cache flushes take a void *
Make flush_data_cache_local, flush_instruction_cache_local and
flush_tlb_all_local take a void * so they don't have to be cast
when using on_each_cpu().  This becomes a problem when on_each_cpu
is a macro (as it is in current -mm).

Also move the prototype of flush_tlb_all_local into tlbflush.h and
remove its declaration from .c files.

Signed-off-by: Matthew Wilcox <willy@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-01-10 21:49:21 -05:00
Arjan van de Ven
2acbb8c657 [PATCH] mutex subsystem, add default include/asm-*/mutex.h files
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 <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2006-01-09 15:59:19 -08:00
Ingo Molnar
ffbf670f5c [PATCH] mutex subsystem, add atomic_xchg() to all arches
add atomic_xchg() to all the architectures. Needed by the new mutex code.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
2006-01-09 15:59:17 -08:00
Jeff Dike
f8aaeacec1 [PATCH] consolidate asm/futex.h
Most of the architectures have the same asm/futex.h.  This consolidates them
into asm-generic, with the arches including it from their own asm/futex.h.

In the case of UML, this reverts the old broken futex.h and goes back to using
the same one as almost everyone else.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:39 -08:00
Ravikiran G Thirumalai
1fd73c6b67 [PATCH] Kill L1_CACHE_SHIFT_MAX
Kill L1_CACHE_SHIFT from all arches.  Since L1_CACHE_SHIFT_MAX is not used
anymore with the introduction of INTERNODE_CACHE, kill L1_CACHE_SHIFT_MAX.

Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08 20:13:39 -08:00
Christoph Lameter
d3cb487149 [PATCH] atomic_long_t & include/asm-generic/atomic.h V2
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 <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:29 -08:00
Badari Pulavarty
f6b3ec238d [PATCH] madvise(MADV_REMOVE): remove pages from tmpfs shm backing store
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 Arcangeli

Databases 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 <pbadari@us.ibm.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Andrea Arcangeli <andrea@suse.de>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-06 08:33:22 -08:00
Stephen Hemminger
3821af2fe1 [FLS64]: generic version
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03 13:11:06 -08:00
Matthew Wilcox
29a622dd2b [PARISC] Always spinlock tlb flush operations to ensure preempt safety
Since taking a spinlock disables preempt, and we need to spinlock tlb flush
on SMP for N class, we might as well just spinlock on uniprocessor machines
too.

Signed-off-by: Matthew Wilcox <willy@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2005-11-17 16:44:14 -05:00
James Bottomley
08dc2ca61e [PARISC] Fix our spinlock implementation
We actually have two separate bad bugs

1. The read_lock implementation spins with disabled interrupts.  This is
completely wrong
2. Our spin_lock_irqsave should check to see if interrupts were enabled
before the call and re-enable interrupts around the inner spin loop.

The problem is that if we spin with interrupts off, we can't receive
IPIs. This has resulted in a bug where SMP machines suddenly spit
smp_call_function timeout messages and hang.

The scenario I've caught is

CPU0 does a flush_tlb_all holding the vmlist_lock for write.
CPU1 tries a cat of /proc/meminfo which tries to acquire vmlist_lock for
     read
CPU1 is now spinning with interrupts disabled
CPU0 tries to execute a smp_call_function to flush the local tlb caches

This is now a deadlock because CPU1 is spinning with interrupts disabled
and can never receive the IPI

Signed-off-by: James Bottomley <jejb@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2005-11-17 16:35:09 -05:00