Commit graph

33 commits

Author SHA1 Message Date
Andrew Morton
5b019e9901 lib/idr.c: use kmem_cache_zalloc() for the idr_layer cache
David points out that the idr_remove_all() function returns unused slabs
to the kmem cache, but needs to zero them first or else they will be
uninitialized upon next use.  This causes crashes which have been observed
in the firewire subsystem.

He fixed this by zeroing the object before freeing it in idr_remove_all().

But we agree that simply removing the constructor and zeroing the object
at allocation time is simpler than relying upon slab constructor machinery
and might even be faster.

This problem was introduced by "idr: make idr_remove rcu-safe" (commit
cf481c20c4), which was first released in
2.6.27.

There are no known codesites which trigger this bug in 2.6.27 or 2.6.28.
The post-2.6.28 firewire changes are the only known triggerer.

There might of course be not-yet-discovered triggerers in 2.6.27 and
2.6.28, and there might be out-of-tree triggerers which are added to those
kernel versions.  I'll let the -stable guys decide whether they want to
backport this fix.

Reported-by: David Moore <dcm@acm.org>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Paul E. McKenney <paulmck@us.ibm.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Kristian Hgsberg <krh@redhat.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-15 16:39:40 -08:00
Li Zefan
b098161b4d idr: fix wrong kernel-doc
idr_get_new_above() and ida_get_new_above() return an id in the range of
@staring_id ... 0x7fffffff, not 0 ... 0x7fffffff.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-15 16:39:37 -08:00
Manfred Spraul
711a49a07f lib/idr.c: Fix bug introduced by RCU fix
The last patch to lib/idr.c caused a bug if idr_get_new_above() was
called on an empty idr.

Usually, nodes stay on the same layer.  New layers are added to the top
of the tree.

The exception is idr_get_new_above() on an empty tree: In this case, the
new root node is first added on layer 0, then moved upwards.  p->layer
was not updated.

As usual: You shall never rely on the source code comments, they will
only mislead you.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-10 13:34:33 -08:00
Manfred Spraul
6ff2d39b91 lib/idr.c: fix rcu related race with idr_find
2nd part of the fixes needed for
http://bugzilla.kernel.org/show_bug.cgi?id=11796.

When the idr tree is either grown or shrunk, then the update to the number
of layers and the top pointer were not atomic.  This race caused crashes.

The attached patch fixes that by replicating the layers counter in each
layer, thus idr_find doesn't need idp->layers anymore.

Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Clement Calmels <cboulte@gmail.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-01 19:55:25 -08:00
Alexey Dobriyan
51cc50685a SL*B: drop kmem cache argument from constructor
Kmem cache passed to constructor is only needed for constructors that are
themselves multiplexeres.  Nobody uses this "feature", nor does anybody uses
passed kmem cache in non-trivial way, so pass only pointer to object.

Non-trivial places are:
	arch/powerpc/mm/init_64.c
	arch/powerpc/mm/hugetlbpage.c

This is flag day, yes.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Jon Tollefson <kniht@linux.vnet.ibm.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Matt Mackall <mpm@selenic.com>
[akpm@linux-foundation.org: fix arch/powerpc/mm/hugetlbpage.c]
[akpm@linux-foundation.org: fix mm/slab.c]
[akpm@linux-foundation.org: fix ubifs]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 12:00:07 -07:00
Nadia Derbey
cf481c20c4 idr: make idr_remove rcu-safe
Introduce the free_layer() routine: it is the one that actually frees memory
after a grace period has elapsed.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Reviewed-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Jim Houston <jim.houston@comcast.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:42 -07:00
Nadia Derbey
f9c46d6ea5 idr: make idr_find rcu-safe
Make idr_find rcu-safe: it can now be called inside an rcu_read critical
section.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Reviewed-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Jim Houston <jim.houston@comcast.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:42 -07:00
Nadia Derbey
3219b3b745 idr: make idr_get_new* rcu-safe
Make the idr_get_new* routines rcu-safe.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Reviewed-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Jim Houston <jim.houston@comcast.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:42 -07:00
Nadia Derbey
944ca05c7b idr: error checking factorization
Do some code factorization in the return code analysis.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Jim Houston <jim.houston@comcast.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:41 -07:00
Nadia Derbey
f098ad655f idr: fix a printk call
Fix the incomplete printk call.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Reviewed-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Jim Houston <jim.houston@comcast.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:41 -07:00
Nadia Derbey
4ae537892a idr: rename some of the idr APIs internal routines
This is a trivial patch that renames:

   . alloc_layer to get_from_free_list since it idr_pre_get that actually
     allocates memory.
   . free_layer to move_to_free_list since memory is not actually freed there.

This makes things more clear for the next patches.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Reviewed-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Jim Houston <jim.houston@comcast.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 10:53:41 -07:00
Nadia Derbey
af8e2a4cb9 idr: fix idr_remove()
The return inside the loop makes us free only a single layer.

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Jim Houston <jim.houston@comcast.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-01 08:04:00 -07:00
Akinobu Mita
199f0ca514 idr: create idr_layer_cache at boot time
Avoid a possible kmem_cache_create() failure by creating idr_layer_cache
unconditionary at boot time rather than creating it on-demand when idr_init()
is called the first time.

This change also enables us to eliminate the check every time idr_init() is
called.

[akpm@linux-foundation.org: rename init_id_cache() to idr_init_cache()]
[akpm@linux-foundation.org: fix alpha build]
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:25 -07:00
Christoph Lameter
4ba9b9d0ba Slab API: remove useless ctor parameter and reorder parameters
Slab constructors currently have a flags parameter that is never used.  And
the order of the arguments is opposite to other slab functions.  The object
pointer is placed before the kmem_cache pointer.

Convert

        ctor(void *object, struct kmem_cache *s, unsigned long flags)

to

        ctor(struct kmem_cache *s, void *object)

throughout the kernel

[akpm@linux-foundation.org: coupla fixes]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:45 -07:00
Al Viro
5ba253313d more low-hanging fruits - kernel, fs, lib signedness
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-14 12:41:52 -07:00
Oleg Nesterov
6ace06dc68 idr_remove_all: kill unused variable
"error" is always equal to 0.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-31 15:39:42 -07:00
Paul Mundt
20c2df83d2 mm: Remove slab destructors from kmem_cache_create().
Slab destructors were no longer supported after Christoph's
c59def9f22 change. They've been
BUGs for both slab and slub, and slob never supported them
either.

This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-07-20 10:11:58 +09:00
Kristian Hoegsberg
23936cc0b5 lib: add idr_remove_all
Remove all ids from the given idr tree.  idr_destroy() only frees up
unused, cached idp_layers, but this function will remove all id mappings
and leave all idp_layers unused.

A typical clean-up sequence for objects stored in an idr tree, will use
idr_for_each() to free all objects, if necessay, then idr_remove_all() to
remove all ids, and idr_destroy() to free up the cached idr_layers.

Signed-off-by: Kristian Hoegsberg <krh@redhat.com>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:34 -07:00
Kristian Hoegsberg
96d7fa421e lib: add idr_for_each()
This patch adds an iterator function for the idr data structure.  Compared
to just iterating through the idr with an integer and idr_find, this
iterator is (almost, but not quite) linear in the number of elements, as
opposed to the number of integers in the range covered by the idr.  This
makes a difference for sparse idrs, but more importantly, it's a nicer way
to iterate through the elements.

The drm subsystem is moving to idr for tracking contexts and drawables, and
with this change, we can use the idr exclusively for tracking these
resources.

[akpm@linux-foundation.org: fix comment]
Signed-off-by: Kristian Hoegsberg <krh@redhat.com>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 09:05:34 -07:00
Tejun Heo
72dba584b6 ida: implement idr based id allocator
Implement idr based id allocator.  ida is used the same way idr is
used but lacks id -> ptr translation and thus consumes much less
memory.  struct ida_bitmap is attached as leaf nodes to idr tree which
is managed by the idr code.  Each ida_bitmap is 128bytes long and
contains slightly less than a thousand slots.

ida is more aggressive with releasing extra resources acquired using
ida_pre_get().  After every successful id allocation, ida frees one
reserved idr_layer if possible.  Reserved ida_bitmap is not freed
automatically but only one ida_bitmap is reserved and it's almost
always used right away.  Under most circumstances, ida won't hold on
to memory for too long which isn't actively used.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-11 16:09:03 -07:00
Tejun Heo
e33ac8bdb0 idr: separate out idr_mark_full()
Separate out idr_mark_full() from sub_alloc() and make marking the
allocated slot full the responsibility of idr_get_new_above_int().

Allocation part of idr_get_new_above_int() is renamed to
idr_get_empty_slot().  New idr_get_new_above_int() allocates a slot
using the function, install the user pointer and marks it full using
idr_mark_full().

This change doesn't introduce any behavior change.  This will be
used by ida.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-11 16:09:03 -07:00
Tejun Heo
7aae6dd80e idr: fix obscure bug in allocation path
In sub_alloc(), when bitmap search fails, it goes up one level to
continue search.  This is done by updating the id cursor and searching
the upper level again.  If the cursor was at the end of the upper
level, we need to go further than that.

This wasn't implemented and when that happens the part of the cursor
which indexes into the upper level wraps and sub_alloc() ends up
searching the wrong bitmap.  It allocates id which doesn't match the
actual slot.

This patch fixes this by restarting from the top if the search needs
to go higher than one level.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-11 16:09:02 -07:00
Robert P. J. Day
72fd4a35a8 [PATCH] Numerous fixes to kernel-doc info in source files.
A variety of (mostly) innocuous fixes to the embedded kernel-doc content in
source files, including:

  * make multi-line initial descriptions single line
  * denote some function names, constants and structs as such
  * change erroneous opening '/*' to '/**' in a few places
  * reword some text for clarity

Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11 10:51:32 -08:00
Christoph Lameter
e18b890bb0 [PATCH] slab: remove kmem_cache_t
Replace all uses of kmem_cache_t with struct kmem_cache.

The patch was generated using the following script:

	#!/bin/sh
	#
	# Replace one string by another in all the kernel sources.
	#

	set -e

	for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
		quilt add $file
		sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
		mv /tmp/$$ $file
		quilt refresh
	done

The script was run like this

	sh replace kmem_cache_t "struct kmem_cache"

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07 08:39:25 -08:00
Roland Dreier
c259cc2812 [PATCH] Convert idr's internal locking to _irqsave variant
Currently, the code in lib/idr.c uses a bare spin_lock(&idp->lock) to do
internal locking.  This is a nasty trap for code that might call idr
functions from different contexts; for example, it seems perfectly
reasonable to call idr_get_new() from process context and idr_remove() from
interrupt context -- but with the current locking this would lead to a
potential deadlock.

The simplest fix for this is to just convert the idr locking to use
spin_lock_irqsave().

In particular, this fixes a very complicated locking issue detected by
lockdep, involving the ib_ipoib driver's priv->lock and dev->_xmit_lock,
which get involved with the ib_sa module's query_idr.lock.

Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Zach Brown <zach.brown@oracle.com>,
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-14 21:53:54 -07:00
Jeff Mahoney
5806f07cd2 [PATCH] lib: add idr_replace
This patch adds idr_replace() to replace an existing pointer in a single
operation.

Device-mapper will use this to update the pointer it stored against a given
id.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:34 -07:00
Sonny Rao
1eec00565d [PATCH] fix race in idr code
I ran into a bug where the kernel died in the idr code:

cpu 0x1d: Vector: 300 (Data Access) at [c000000b7096f710]
    pc: c0000000001f8984: .idr_get_new_above_int+0x140/0x330
    lr: c0000000001f89b4: .idr_get_new_above_int+0x170/0x330
    sp: c000000b7096f990
   msr: 800000000000b032
   dar: 0
 dsisr: 40010000
  current = 0xc000000b70d43830
  paca    = 0xc000000000556900
    pid   = 2022, comm = hwup
1d:mon> t
[c000000b7096f990] c0000000000d2ad8 .expand_files+0x2e8/0x364 (unreliable)
[c000000b7096faa0] c0000000001f8bf8 .idr_get_new_above+0x18/0x68
[c000000b7096fb20] c00000000002a054 .init_new_context+0x5c/0xf0
[c000000b7096fbc0] c000000000049dc8 .copy_process+0x91c/0x1404
[c000000b7096fcd0] c00000000004a988 .do_fork+0xd8/0x224
[c000000b7096fdc0] c00000000000ebdc .sys_clone+0x5c/0x74
[c000000b7096fe30] c000000000008950 .ppc_clone+0x8/0xc
2006-06-25 10:01:26 -07:00
Jesper Juhl
e15ae2dd3e [PATCH] Whitespace and CodingStyle cleanup for lib/idr.c
Cleanup trailing whitespace, blank lines, CodingStyle issues etc, for
lib/idr.c

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 17:37:19 -08:00
Al Viro
fd4f2df24b [PATCH] gfp_t: lib/*
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-28 08:16:47 -07:00
Andrew Morton
8d3b35914a [PATCH] inotify/idr leak fix
Fix a bug which was reported and diagnosed by
Stefan Jones <stefan.jones@churchillrandoms.co.uk>

IDR trees include a cache of idr_layer objects.  There's no way to destroy
this cache, so when we discard an overall idr tree we end up leaking some
memory.

Add and use idr_destroy() for this.  v9fs and infiniband also need to use
idr_destroy() to avoid leaks.

Or, we make the cache global, like radix_tree_preload().  Which is probably
better.  Later.

Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Robert Love <rml@novell.com>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-23 16:38:39 -07:00
John McCutchan
7c657f2f25 [PATCH] Document idr_get_new_above() semantics, update inotify
There is an off by one problem with idr_get_new_above.

The comment and function name suggest that it will return an id >
starting_id, but it actually returned an id >= starting_id, and kernel
callers other than inotify treated it as such.

The patch below fixes the comment, and fixes inotifys usage.  The
function name still doesn't match the behaviour, but it never did.

Signed-off-by: John McCutchan <ttb@tentacle.dhs.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-26 11:32:57 -07:00
Zaur Kambarov
589777eab7 [PATCH] coverity: idr_get_new_above_int() overrun fix
This patch fixes overrun of array pa:
92   		struct idr_layer *pa[MAX_LEVEL];

in

98   		l = idp->layers;
99   		pa[l--] = NULL;

by passing idp->layers, set in
202  		idp->layers = layers;
to function  sub_alloc in
203  		v = sub_alloc(idp, ptr, &id);

Signed-off-by: Zaur Kambarov <zkambarov@coverity.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:12 -07:00
Linus Torvalds
1da177e4c3 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!
2005-04-16 15:20:36 -07:00