Commit graph android_kernel_sony_sdm845/drivers/char/mem.c
Message SHA1
make /dev/kmem a config option
Make /dev/kmem a config option; /dev/kmem is VERY rarely used, and when
used, it's generally for no good (rootkits tend to be the most common
users).  With this config option, users have the choice to disable
/dev/kmem, saving some size as well.

A patch to disable /dev/kmem has been in the Fedora and RHEL kernels for
4+ years now without any known problems or legit users of /dev/kmem.

[akpm@linux-foundation.org: make CONFIG_DEVKMEM default to y]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Arjan van de Ven   authored and   Linus Torvalds   commited 2008-04-29 08:05:59 -07:00
b781ecb6a3
x86: PAT use reserve free memtype in mmap of /dev/mem
Use reserve_memtype and free_memtype wrappers for /dev/mem mmaps. The memtype
is slightly complicated here, given that we have to support existing X mappings.
We fallback on UC_MINUS for that.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

venkatesh.pallipadi@intel.com   authored and   Ingo Molnar   commited 2008-04-24 23:40:47 +02:00
e7f260a276
x86: PAT phys_mem_access_prot_allowed for dev/mem mmap
Introduce phys_mem_access_prot_allowed(), which checks whether the mapping
is possible, without any conflicts and returns success or failure based on that.
phys_mem_access_prot() by itself does not allow failure case. This ability
to return error is needed for PAT where we may have aliasing conflicts.

x86 setup __HAVE_PHYS_MEM_ACCESS_PROT and move x86 specific code out of
/dev/mem into arch specific area.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

venkatesh.pallipadi@intel.com   authored and   Ingo Molnar   commited 2008-04-24 23:40:47 +02:00
f0970c13b6
x86: PAT avoid aliasing in /dev/mem read/write
Add xlate and unxlate around /dev/mem read/write. This sets up the mapping
that can be used for /dev/mem read and write without aliasing worries.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

venkatesh.pallipadi@intel.com   authored and   Ingo Molnar   commited 2008-04-24 23:40:47 +02:00
e045fb2a98
devmem: add range_is_allowed() check to mmap of /dev/mem
Earlier patch that introduced CONFIG_NONPROMISC_DEVMEM, did the
range_is_allowed() check only for read and write. Add range_is_allowed()
check to mmap of /dev/mem as well.

Changes the paramaters of range_is_allowed() to pfn and size to handle
more than 32 bits of physical address on 32 bit arch cleanly.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Venki Pallipadi   authored and   Ingo Molnar   commited 2008-04-24 23:40:47 +02:00
e2beb3eae6
x86: introduce /dev/mem restrictions with a config option
This patch introduces a restriction on /dev/mem: Only non-memory can be
read or written unless the newly introduced config option is set.

The X server needs access to /dev/mem for the PCI space, but it doesn't need
access to memory; both the file permissions and SELinux permissions of /dev/mem
just make X effectively super-super powerful. With the exception of the
BIOS area, there's just no valid app that uses /dev/mem on actual memory.
Other popular users of /dev/mem are rootkits and the like.
(note: mmap access of memory via /dev/mem was already not allowed since
a really long time)

People who want to use /dev/mem for kernel debugging can enable the config
option.

The restrictions of this patch have been in the Fedora and RHEL kernels for
at least 4 years without any problems.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Arjan van de Ven   authored and   Ingo Molnar   commited 2008-04-24 23:40:47 +02:00
ae531c26c5
x86 merge fallout: uml
Don't undef __i386__/__x86_64__ in uml anymore, make sure that (few) places
that required adjusting the ifdefs got those.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Al Viro   authored and   Linus Torvalds   commited 2007-10-29 07:41:32 -07:00
ca5cd877ae
mm: bdi init hooks
provide BDI constructor/destructor hooks

[akpm@linux-foundation.org: compile fix]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Peter Zijlstra   authored and   Linus Torvalds   commited 2007-10-17 08:42:45 -07:00
e0bf68ddec
remove ZERO_PAGE
The commit b5810039a5 contains the note

  A last caveat: the ZERO_PAGE is now refcounted and managed with rmap
  (and thus mapcounted and count towards shared rss).  These writes to
  the struct page could cause excessive cacheline bouncing on big
  systems.  There are a number of ways this could be addressed if it is
  an issue.

And indeed this cacheline bouncing has shown up on large SGI systems.
There was a situation where an Altix system was essentially livelocked
tearing down ZERO_PAGE pagetables when an HPC app aborted during startup.
This situation can be avoided in userspace, but it does highlight the
potential scalability problem with refcounting ZERO_PAGE, and corner
cases where it can really hurt (we don't want the system to livelock!).

There are several broad ways to fix this problem:
1. add back some special casing to avoid refcounting ZERO_PAGE
2. per-node or per-cpu ZERO_PAGES
3. remove the ZERO_PAGE completely

I will argue for 3. The others should also fix the problem, but they
result in more complex code than does 3, with little or no real benefit
that I can see.

Why? Inserting a ZERO_PAGE for anonymous read faults appears to be a
false optimisation: if an application is performance critical, it would
not be doing many read faults of new memory, or at least it could be
expected to write to that memory soon afterwards. If cache or memory use
is critical, it should not be working with a significant number of
ZERO_PAGEs anyway (a more compact representation of zeroes should be
used).

As a sanity check -- mesuring on my desktop system, there are never many
mappings to the ZERO_PAGE (eg. 2 or 3), thus memory usage here should not
increase much without it.

When running a make -j4 kernel compile on my dual core system, there are
about 1,000 mappings to the ZERO_PAGE created per second, but about 1,000
ZERO_PAGE COW faults per second (less than 1 ZERO_PAGE mapping per second
is torn down without being COWed). So removing ZERO_PAGE will save 1,000
page faults per second when running kbuild, while keeping it only saves
less than 1 page clearing operation per second. 1 page clear is cheaper
than a thousand faults, presumably, so there isn't an obvious loss.

Neither the logical argument nor these basic tests give a guarantee of no
regressions. However, this is a reasonable opportunity to try to remove
the ZERO_PAGE from the pagefault path. If it is found to cause regressions,
we can reintroduce it and just avoid refcounting it.

The /dev/zero ZERO_PAGE usage and TLB tricks also get nuked.  I don't see
much use to them except on benchmarks.  All other users of ZERO_PAGE are
converted just to use ZERO_PAGE(0) for simplicity. We can look at
replacing them all and maybe ripping out ZERO_PAGE completely when we are
more satisfied with this solution.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus "snif" Torvalds <torvalds@linux-foundation.org>

Nick Piggin   authored and   Linus Torvalds   commited 2007-10-16 09:42:53 -07:00
557ed1fa26
Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus: (62 commits)
  [MIPS] PNX8550: Cleanup proc code.
  [MIPS] WRPPMC: Fix build.
  [MIPS] Yosemite: Fix modpost warnings.
  [MIPS] Change names of local variables to silence sparse
  [MIPS] SB1: Fix modpost warning.
  [MIPS] PNX: Fix modpost warnings.
  [MIPS] Alchemy: Fix modpost warnings.
  [MIPS] Non-FPAFF: Fix warning.
  [MIPS] DEC: Fix modpost warning.
  [MIPS] MIPSsim: Enable MIPSsim virtual network driver.
  [MIPS] Delete Ocelot 3 support.
  [MIPS] remove LASAT Networks platforms support
  [MIPS] Early check for SMTC kernel on non-MT processor
  [MIPS] Add debugfs files to show fpuemu statistics
  [MIPS] Add some debugfs files to debug unaligned accesses
  [MIPS] rbtx4938: Fix secondary PCIC and glue internal NICs
  [MIPS] tc35815: Load MAC address via platform_device
  [MIPS] Move FPU affinity code into separate file.
  [MIPS] Make ioremap() work on TX39/49 special unmapped segment
  [MIPS] rbtx4938: Update and minimize defconfig
  ...

Linus Torvalds   commited 2007-07-10 14:48:43 -07:00
0f166396e7
[MIPS] Hook for platforms to define cachability of /dev/mem regions
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Ralf Baechle   commited 2007-07-10 17:32:56 +01:00
24e9d0b96d
splice: divorce the splice structure/function definitions from the pipe header
We need to move even more stuff into the header so that folks can use
the splice_to_pipe() implementation instead of open-coding a lot of
pipe knowledge (see relay implementation), so move to our own header
file finally.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

Jens Axboe   commited 2007-07-10 08:04:14 +02:00
d6b29d7cee
Make /dev/port conditional on config symbol
Instead of having /dev/port support dependent in multiple places on a
string of preprocessor symbols, define a new configuration directive for
it.  This ensures that all four places remain consistent with each other.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Russell King   authored and   Linus Torvalds   commited 2007-05-08 11:15:07 -07:00
4f911d64e0
header cleaning: don't include smp_lock.h when not used
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Randy Dunlap   authored and   Linus Torvalds   commited 2007-05-08 11:15:07 -07:00
e63340ae6b
fix bogon in /dev/mem mmap'ing on nommu
While digging through my MAP_FIXED changes, I found that rather obvious
bug in /dev/mem mmap implementation for nommu archs. get_unmapped_area()
is expected to return an address, not a pfn.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-By: David Howells <dhowells@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Benjamin Herrenschmidt   authored and   Linus Torvalds   commited 2007-04-17 16:36:27 -07:00
8a93258ce3
Revert "[PATCH] Fix up mmap_kmem"
This reverts commit 99a10a60ba.

As per Hugh Dickins:

  "Nadia Derbey has reported that mmap of /dev/kmem no longer works with
   the kernel virtual address as offset, and Franck has confirmed that
   his patch came from a misunderstanding of what an offset means to
   /dev/kmem - whereas his patch description seems to say that he was
   correcting the offset on a few plaforms, there was no such problem to
   correct, and his patch was in fact changing its API on all platforms."

Suggested-by: Hugh Dickins <hugh@veritas.com>
Cc: Franck Bui-Huu <fbuihuu@gmail.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Andi Kleen <ak@suse.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Linus Torvalds   commited 2007-01-22 08:53:24 -08:00
6d3154cc11
[PATCH] read_zero_pagealigned() locking fix
Ramiro Voicu hits the BUG_ON(!pte_none(*pte)) in zeromap_pte_range: kernel
bugzilla 7645.  Right: read_zero_pagealigned uses down_read of mmap_sem,
but another thread's racing read of /dev/zero, or a normal fault, can
easily set that pte again, in between zap_page_range and zeromap_page_range
getting there.  It's been wrong ever since 2.4.3.

The simple fix is to use down_write instead, but that would serialize reads
of /dev/zero more than at present: perhaps some app would be badly
affected.  So instead let zeromap_page_range return the error instead of
BUG_ON, and read_zero_pagealigned break to the slower clear_user loop in
that case - there's no need to optimize for it.

Use -EEXIST for when a pte is found: BUG_ON in mmap_zero (the other user of
zeromap_page_range), though it really isn't interesting there.  And since
mmap_zero wants -EAGAIN for out-of-memory, the zeromaps better return that
than -ENOMEM.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: Ramiro Voicu: <Ramiro.Voicu@cern.ch>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Hugh Dickins   authored and   Linus Torvalds   commited 2006-12-10 09:55:39 -08:00
5fcf7bb73f
[PATCH] struct path: convert char-drivers
Signed-off-by: Josef Sipek <jsipek@fsl.cs.sunysb.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Josef Sipek   authored and   Linus Torvalds   commited 2006-12-08 08:28:44 -08:00
a7113a9662
Driver core: change mem class_devices to be real devices
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Greg Kroah-Hartman   commited 2006-12-01 14:52:00 -08:00
ebf644c462
Include proper header file for PFN_DOWN()
The recent commit (99a10a60ba) to fix up
mmap_kmem() broke compiles because it used PFN_DOWN() without including
<linux/pfn.h>.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Linus Torvalds   commited 2006-10-13 08:42:10 -07:00
b8a3ad5b53
[PATCH] Fix up mmap_kmem
vma->vm_pgoff is an pfn _offset_ relatif to the begining
of the memory start. The previous code was doing at first:

	vma->vm_pgoff << PAGE_SHIFT

which results into a wrong physical address since some
platforms have a physical mem start that can be different
from 0. After that the previous call __pa() on this
wrong physical address, however __pa() is used to convert
a _virtual_ address into a physical one.

This patch rewrites this convertion. It calculates the
pfn of PAGE_OFFSET which is the pfn of the mem start
then it adds the vma->vm_pgoff to it.

It also uses virt_to_phys() instead of __pa() since the
latter shouldn't be used by drivers.

Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Franck Bui-Huu   authored and   Linus Torvalds   commited 2006-10-13 08:35:38 -07:00
99a10a60ba
[PATCH] mem driver: fix conditional on isa i/o support
This change corrects the logic on the preprocessor conditionals that
include support for ISA port i/o (/dev/ioports) into the mem character
driver.

This fixes the following error when building for powerpc platforms with
CONFIG_PCI=n.

  drivers/built-in.o: undefined reference to `pci_io_base'

Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com>
Acked-by: Linas Vepstas <lins@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Geoff Levand   authored and   Linus Torvalds   commited 2006-09-29 09:18:22 -07:00
153dcc54df
[PATCH] NOMMU: Set BDI capabilities for /dev/mem and /dev/kmem
Set the backing device info capabilities for /dev/mem and /dev/kmem to
permit direct sharing under no-MMU conditions and full mapping capabilities
under MMU conditions.  Make the BDI used by these available to all directly
mappable character devices.

Also comment the capabilities for /dev/zero.

[akpm@osdl.org: ifdef reductions]
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

David Howells   authored and   Linus Torvalds   commited 2006-09-27 08:26:14 -07:00
5da6185bca
[PATCH] make valid_mmap_phys_addr_range() take a pfn
Newer ARMs have a 40 bit physical address space, but mapping physical
memory above 4G needs a special page table format which we (currently?) do
not use for userspace mappings, so what happens instead is that mapping an
address >= 4G will happily discard the upper bits and wrap.

There is a valid_mmap_phys_addr_range() arch hook where we could check for
>= 4G addresses and deny the mapping, but this hook takes an unsigned long
address:

	static inline int valid_mmap_phys_addr_range(unsigned long addr, size_t size);

And drivers/char/mem.c:mmap_mem() calls it like this:

	static int mmap_mem(struct file * file, struct vm_area_struct * vma)
	{
		size_t size = vma->vm_end - vma->vm_start;

		if (!valid_mmap_phys_addr_range(vma->vm_pgoff << PAGE_SHIFT, size))

So that's not much help either.

This patch makes the hook take a pfn instead of a phys address.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Lennert Buytenhek   authored and   Linus Torvalds   commited 2006-07-10 13:24:25 -07:00
06c67befee
[PATCH] make more file_operation structs static
Mark the static struct file_operations in drivers/char as const.  Making
them const prevents accidental bugs, and moves them to the .rodata section
so that they no longer do any false sharing; in addition with the proper
debug option they are then protected against corruption..

[akpm@osdl.org: build fix]
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Arjan van de Ven   authored and   Linus Torvalds   commited 2006-07-03 15:26:59 -07:00
62322d2554
Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

Jörn Engel   authored and   Adrian Bunk   commited 2006-06-30 19:25:36 +02:00
6ab3d5624e
[PATCH] devfs: Remove the devfs_fs_kernel.h file from the tree
Also fixes up all files that #include it.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Greg Kroah-Hartman   commited 2006-06-26 12:25:08 -07:00
ff23eca3e8
[PATCH] devfs: Remove devfs_mk_cdev() function from the kernel tree
Removes the devfs_mk_cdev() function and all callers of it.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Greg Kroah-Hartman   commited 2006-06-26 12:25:07 -07:00
7c69ef7974
[PATCH] splice: add ->splice_write support for /dev/null
Useful for testing.

Signed-off-by: Jens Axboe <axboe@suse.de>

Jens Axboe   commited 2006-04-26 14:40:08 +02:00
1ebd32fc54
[PATCH] mark f_ops const in the inode
Mark the f_ops members of inodes as const, as well as fix the
ripple-through this causes by places that copy this f_ops and then "do
stuff" with it.

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Arjan van de Ven   authored and   Linus Torvalds   commited 2006-03-28 09:16:05 -08:00
99ac48f54a
[PATCH] EFI, /dev/mem: simplify efi_mem_attribute_range()
Pass the size, not a pointer to the size, to efi_mem_attribute_range().

This function validates memory regions for the /dev/mem read/write/mmap paths.
The pointer allows arches to reduce the size of the range, but I think that's
unnecessary complexity.  Simplifying it will let me use
efi_mem_attribute_range() to improve the ia64 ioremap() implementation.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Matt Domsch <Matt_Domsch@dell.com>
Cc: "Tolentino, Matthew E" <matthew.e.tolentino@intel.com>
Cc: "Brown, Len" <len.brown@intel.com>
Cc: Andi Kleen <ak@muc.de>
Acked-by: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Bjorn Helgaas   authored and   Linus Torvalds   commited 2006-03-26 08:56:54 -08:00
136939a2b5
[PATCH] adjust /dev/{kmem,mem,port} write handlers
The /dev/mem and /dev/kmem write handlers weren't fully POSIX compliant in
that they wouldn't always force the file pointer to be updated when
returning success status.

The /dev/port write handler was inconsistent with the /dev/mem and
/dev/kmem handlers in that when encountering a -EFAULT condition after
already having written a number of items it would return -EFAULT rather
than the number of bytes written.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Jan Beulich   authored and   Linus Torvalds   commited 2006-03-25 08:22:55 -08:00
c654d60e8f
[PATCH] powerpc: iSeries fixes for build with no PCI
This reverts part of "ppc64 iSeries: allow build with no PCI"
(145d01e428) which affected generic code
and applies a fix in the arch specific code.

Commit "partly merge iseries do_IRQ"
(5fee9b3b39eb55c7e3619a3b36ceeabffeb8f144) introduced iSeries_get_irq
which was only available if CONFIG_PCI is set.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

Stephen Rothwell   authored and   Paul Mackerras   commited 2006-01-12 20:09:30 +11:00
ee2cdecec4
[PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_sem
This patch converts the inode semaphore to a mutex. I have tested it on
XFS and compiled as much as one can consider on an ia64. Anyway your
luck with it might be different.

Modified-by: Ingo Molnar <mingo@elte.hu>

(finished the conversion)

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Jes Sorensen   authored and   Ingo Molnar   commited 2006-01-09 15:59:24 -08:00
1b1dcc1b57
[PATCH] /dev/mem: validate mmap requests
Add a hook so architectures can validate /dev/mem mmap requests.

This is analogous to validation we already perform in the read/write
paths.

The identity mapping scheme used on ia64 requires that each 16MB or
64MB granule be accessed with exactly one attribute (write-back or
uncacheable).  This avoids "attribute aliasing", which can cause a
machine check.

Sample problem scenario:
  - Machine supports VGA, so it has uncacheable (UC) MMIO at 640K-768K
  - efi_memmap_init() discards any write-back (WB) memory in the first granule
  - Application (e.g., "hwinfo") mmaps /dev/mem, offset 0
  - hwinfo receives UC mapping (the default, since memmap says "no WB here")
  - Machine check abort (on chipsets that don't support UC access to WB
    memory, e.g., sx1000)

In the scenario above, the only choices are
  - Use WB for hwinfo mmap.  Can't do this because it causes attribute
    aliasing with the UC mapping for the VGA MMIO space.
  - Use UC for hwinfo mmap.  Can't do this because the chipset may not
    support UC for that region.
  - Disallow the hwinfo mmap with -EINVAL.  That's what this patch does.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Bjorn Helgaas   authored and   Linus Torvalds   commited 2006-01-08 20:14:02 -08:00
80851ef2a5
[PATCH] /dev/mem __HAVE_PHYS_MEM_ACCESS_PROT tidy-up
Tidy up __HAVE_PHYS_MEM_ACCESS_PROT usage to make mmap_mem() easier to read.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Bjorn Helgaas   authored and   Linus Torvalds   commited 2006-01-08 20:14:02 -08:00
44ac841390
[PATCH] kmsg_write: don't return printk return value
kmsg_write returns with printk, so some programs may be confused by a
successful write() with a return value different than the buffer length.

# /bin/echo something > /dev/kmsg
/bin/echo: write error: Inappropriate ioctl for device

The drawbacks is that the printk return value can no more be quickly
checked from userspace.

Signed-off-by: Guillaume Chazarain <guichaz@yahoo.fr>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Guillaume Chazarain   authored and   Linus Torvalds   commited 2006-01-08 20:13:53 -08:00
cd140a5c1f
mm: re-architect the VM_UNPAGED logic
This replaces the (in my opinion horrible) VM_UNMAPPED logic with very
explicit support for a "remapped page range" aka VM_PFNMAP.  It allows a
VM area to contain an arbitrary range of page table entries that the VM
never touches, and never considers to be normal pages.

Any user of "remap_pfn_range()" automatically gets this new
functionality, and doesn't even have to mark the pages reserved or
indeed mark them any other way.  It just works.  As a side effect, doing
mmap() on /dev/mem works for arbitrary ranges.

Sparc update from David in the next commit.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Linus Torvalds   commited 2005-11-28 14:34:23 -08:00
6aab341e0a
[PATCH] unpaged: ZERO_PAGE in VM_UNPAGED
It's strange enough to be looking out for anonymous pages in VM_UNPAGED areas,
let's not insert the ZERO_PAGE there - though whether it would matter will
depend on what we decide about ZERO_PAGE refcounting.

But whereas do_anonymous_page may (exceptionally) be called on a VM_UNPAGED
area, do_no_page should never be: just BUG_ON.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Hugh Dickins   authored and   Linus Torvalds   commited 2005-11-22 09:13:42 -08:00
f57e88a8d8
Merge ../linux-2.6 by hand
Paul Mackerras   commited 2005-10-31 13:37:12 +11:00
23fd07750a
[PATCH] ppc: make phys_mem_access_prot() work with pfns instead of addresses
Change the phys_mem_access_prot() function to take a pfn instead of an
address.  This allows mmap64() to work on /dev/mem for addresses above 4G
on 32-bit architectures.  We start with a pfn in mmap_mem(), so there's no
need to convert to an address; in fact, it's actively bad, since the
conversion can overflow when the address is above 4G.

Similarly fix the ppc32 page_is_ram() function to avoid a conversion to an
address by directly comparing to max_pfn.  Working with max_pfn instead of
high_memory fixes page_is_ram() to give the right answer for highmem pages.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

Roland Dreier   authored and   Paul Mackerras   commited 2005-10-29 14:25:49 +10:00
8b150478ae
[PATCH] Driver Core: fix up all callers of class_device_create()
The previous patch adding the ability to nest struct class_device
changed the paramaters to the call class_device_create().  This patch
fixes up all in-kernel users of the function.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Greg Kroah-Hartman   commited 2005-10-28 09:52:52 -07:00
53f4654272
[PATCH] remove a dead extern in mem.c
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Christoph Hellwig   authored and   Linus Torvalds   commited 2005-09-07 16:57:23 -07:00
edf83015fc
Fix up mmap of /dev/kmem
This leaves the issue of whether we should deprecate the whole thing (or
if we should check the whole mmap range, for that matter) open. Just do
the minimal fix for now.

Linus Torvalds   commited 2005-08-13 14:22:59 -07:00
4bb82551e1
[PATCH] kexec code cleanup
o Following patch provides purely cosmetic changes and corrects CodingStyle
  guide lines related certain issues like below in kexec related files

  o braces for one line "if" statements, "for" loops,
  o more than 80 column wide lines,
  o No space after "while", "for" and "switch" key words

o Changes:
  o take-2: Removed the extra tab before "case" key words.
  o take-3: Put operator at the end of line and space before "*/"

Signed-off-by: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Maneesh Soni   authored and   Linus Torvalds   commited 2005-06-25 16:24:55 -07:00
72414d3f1d
[PATCH] kdump: cleanups for dump file access in linear raw format
Removed the dependency on backup region.  Now all the information is encoded
in ELF format.  /dev/oldmem is a dummy interface.  User space tool need to be
intelligent enough to parse the elf headers and read the relevant memory areas
with the help of /dev/oldmem.

Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Vivek Goyal   authored and   Linus Torvalds   commited 2005-06-25 16:24:54 -07:00
315c215c0a
[PATCH] kdump: Accessing dump file in linear raw format (/dev/oldmem)
Hariprasad Nellitheertha <hari@in.ibm.com>

This patch contains the code that enables us to access the previous kernel's
memory as /dev/oldmem.

Signed-off-by: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Vivek Goyal   authored and   Linus Torvalds   commited 2005-06-25 16:24:54 -07:00
50b1fdbd81
[PATCH] ppc64 iSeries: allow build with no PCI
This patch allows iSeries to build with CONFIG_PCI=n.  This is useful for
partitions that have only virtual I/O.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Stephen Rothwell   authored and   Linus Torvalds   commited 2005-06-21 18:46:31 -07:00
145d01e428
[PATCH] class: convert drivers/char/* to use the new class api instead of class_simple
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

gregkh@suse.de   authored and   Greg Kroah-Hartman   commited 2005-06-20 15:15:08 -07:00
ca8eca6884
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

Linus Torvalds   commited 2005-04-16 15:20:36 -07:00
1da177e4c3