linux-toradex.git/lib/genalloc.c, branch v4.4.93

lib/genalloc.c: start search from start of chunk

2016-11-18T09:48:36+00:00

commit 62e931fac45b17c2a42549389879411572f75804 upstream.

gen_pool_alloc_algo() iterates over the chunks of a pool trying to find
a contiguous block of memory that satisfies the allocation request.

The shortcut

	if (size > atomic_read(&chunk->avail))
		continue;

makes the loop skip over chunks that do not have enough bytes left to
fulfill the request.  There are two situations, though, where an
allocation might still fail:

(1) The available memory is not contiguous, i.e.  the request cannot
    be fulfilled due to external fragmentation.

(2) A race condition.  Another thread runs the same code concurrently
    and is quicker to grab the available memory.

In those situations, the loop calls pool->algo() to search the entire
chunk, and pool->algo() returns some value that is >= end_bit to
indicate that the search failed.  This return value is then assigned to
start_bit.  The variables start_bit and end_bit describe the range that
should be searched, and this range should be reset for every chunk that
is searched.  Today, the code fails to reset start_bit to 0.  As a
result, prefixes of subsequent chunks are ignored.  Memory allocations
might fail even though there is plenty of room left in these prefixes of
those other chunks.

Fixes: 7f184275aa30 ("lib, Make gen_pool memory allocator lockless")
Link: http://lkml.kernel.org/r/1477420604-28918-1-git-send-email-danielmentz@google.com
Signed-off-by: Daniel Mentz 
Reviewed-by: Mathieu Desnoyers 
Acked-by: Will Deacon 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

genalloc: add support of multiple gen_pools per device

2015-09-04T23:54:41+00:00

This change fills devm_gen_pool_create()/gen_pool_get() "name" argument
stub with contents and extends of_gen_pool_get() functionality on this
basis.

If there is no associated platform device with a device node passed to
of_gen_pool_get(), the function attempts to get a label property or device
node name (= repeats MTD OF partition standard) and seeks for a named
gen_pool registered by device of the parent device node.

The main idea of the change is to allow registration of independent
gen_pools under the same umbrella device, say "partitions" on "storage
device", the original functionality of one "partition" per "storage
device" is untouched.

[akpm@linux-foundation.org: fix constness in devres_find()]
[dan.carpenter@oracle.com: freeing const data pointers]
Signed-off-by: Vladimir Zapolskiy 
Cc: Philipp Zabel 
Cc: Greg Kroah-Hartman 
Cc: Russell King 
Cc: Nicolas Ferre 
Cc: Alexandre Belloni 
Cc: Jean-Christophe Plagniol-Villard 
Cc: Shawn Guo 
Cc: Sascha Hauer 
Cc: Mauro Carvalho Chehab 
Cc: Arnd Bergmann 
Signed-off-by: Dan Carpenter 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

genalloc: add name arg to gen_pool_get() and devm_gen_pool_create()

2015-09-04T23:54:41+00:00

This change modifies gen_pool_get() and devm_gen_pool_create() client
interfaces adding one more argument "name" of a gen_pool object.

Due to implementation gen_pool_get() is capable to retrieve only one
gen_pool associated with a device even if multiple gen_pools are created,
fortunately right at the moment it is sufficient for the clients, hence
provide NULL as a valid argument on both producer devm_gen_pool_create()
and consumer gen_pool_get() sides.

Because only one created gen_pool per device is addressable, explicitly
add a restriction to devm_gen_pool_create() to create only one gen_pool
per device, this implies two possible error codes returned by the
function, account it on client side (only misc/sram).  This completes
client side changes related to genalloc updates.

[akpm@linux-foundation.org: gen_pool_get() cleanup]
Signed-off-by: Vladimir Zapolskiy 
Cc: Philipp Zabel 
Cc: Greg Kroah-Hartman 
Cc: Russell King 
Cc: Nicolas Ferre 
Cc: Alexandre Belloni 
Cc: Jean-Christophe Plagniol-Villard 
Cc: Shawn Guo 
Cc: Sascha Hauer 
Cc: Mauro Carvalho Chehab 
Cc: Arnd Bergmann 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

genalloc: rename of_get_named_gen_pool() to of_gen_pool_get()

2015-07-01T02:45:01+00:00

To be consistent with other kernel interface namings, rename
of_get_named_gen_pool() to of_gen_pool_get().  In the original function
name "_named" suffix references to a device tree property, which contains
a phandle to a device and the corresponding device driver is assumed to
register a gen_pool object.

Due to a weak relation and to avoid any confusion (e.g.  in future
possible scenario if gen_pool objects are named) the suffix is removed.

[sfr@canb.auug.org.au: crypto/marvell/cesa - fix up for of_get_named_gen_pool() rename]
Signed-off-by: Vladimir Zapolskiy 
Cc: Nicolas Ferre 
Cc: Philipp Zabel 
Cc: Shawn Guo 
Cc: Sascha Hauer 
Cc: Alexandre Belloni 
Cc: Russell King 
Cc: Mauro Carvalho Chehab 
Cc: Vinod Koul 
Cc: Takashi Iwai 
Cc: Jaroslav Kysela 
Signed-off-by: Stephen Rothwell 
Cc: Herbert Xu 
Cc: Boris BREZILLON 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

genalloc: rename dev_get_gen_pool() to gen_pool_get()

2015-07-01T02:45:01+00:00

To be consistent with other genalloc interface namings, rename
dev_get_gen_pool() to gen_pool_get().  The original omitted "dev_" prefix
is removed, since it points to argument type of the function, and so it
does not bring any useful information.

[akpm@linux-foundation.org: update arch/arm/mach-socfpga/pm.c]
Signed-off-by: Vladimir Zapolskiy 
Acked-by: Nicolas Ferre 
Cc: Philipp Zabel 
Cc: Shawn Guo 
Cc: Sascha Hauer 
Cc: Alexandre Belloni 
Cc: Russell King 
Cc: Mauro Carvalho Chehab 
Cc: Vinod Koul 
Cc: Takashi Iwai 
Cc: Jaroslav Kysela 
Cc: Mark Brown 
Cc: Nicolas Ferre 
Cc: Alan Tull 
Cc: Dinh Nguyen 
Cc: Kevin Hilman 
Cc: Stephen Rothwell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/genalloc.c: check result of devres_alloc()

2015-02-14T05:21:36+00:00

devm_gen_pool_create() calls devres_alloc() and dereferences its result
without checking whether devres_alloc() succeeded.  Check for error and
bail out if it happened.

Coverity-id 1016493.

Signed-off-by: Jan Kara 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/genalloc.c: remove redundant include

2015-02-13T02:54:15+00:00

Removing this include produces byte-identical output, and thus removes a
false dependency.

Signed-off-by: Rasmus Villemoes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/genalloc.c: fix the end addr check in addr_in_gen_pool()

2015-02-13T02:54:14+00:00

Since chunk->end_addr is (chunk->start_addr + size - 1), the end address
to compare should be (start + size - 1).

Signed-off-by: Toshi Kikuchi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/genalloc.c: export devm_gen_pool_create() for modules

2014-12-03T17:36:04+00:00

Modules can use this function for creating pool.

Signed-off-by: Michal Simek 
Acked-by: Lad, Prabhakar 
Cc: Laura Abbott 
Cc: Olof Johansson 
Cc: Catalin Marinas 
Cc: Will Deacon 
Cc: Vladimir Zapolskiy 
Cc: Philipp Zabel 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/genalloc.c: add genpool range check function

2014-10-10T02:25:52+00:00

After allocating an address from a particular genpool, there is no good
way to verify if that address actually belongs to a genpool.  Introduce
addr_in_gen_pool which will return if an address plus size falls
completely within the genpool range.

Signed-off-by: Laura Abbott 
Acked-by: Will Deacon 
Reviewed-by: Olof Johansson 
Reviewed-by: Catalin Marinas 
Cc: Arnd Bergmann 
Cc: David Riley 
Cc: Ritesh Harjain 
Cc: Russell King 
Cc: Thierry Reding 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds