linux.git/lib/genalloc.c, branch v6.6.132

lib/genalloc: fix device leak in of_gen_pool_get()

2025-10-19T14:30:50+00:00

commit 1260cbcffa608219fc9188a6cbe9c45a300ef8b5 upstream.

Make sure to drop the reference taken when looking up the genpool platform
device in of_gen_pool_get() before returning the pool.

Note that holding a reference to a device does typically not prevent its
devres managed resources from being released so there is no point in
keeping the reference.

Link: https://lkml.kernel.org/r/20250924080207.18006-1-johan@kernel.org
Fixes: 9375db07adea ("genalloc: add devres support, allow to find a managed pool by device")
Signed-off-by: Johan Hovold 
Cc: Philipp Zabel 
Cc: Vladimir Zapolskiy 
Cc: 	[3.10+]
Signed-off-by: Andrew Morton 
Signed-off-by: Greg Kroah-Hartman

Merge tag 'devicetree-header-cleanups-for-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

2023-08-31T00:04:28+00:00

Pull devicetree include cleanups from Rob Herring:
 "These are the remaining few clean-ups of DT related includes which
  didn't get applied to subsystem trees"

* tag 'devicetree-header-cleanups-for-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  ipmi: Explicitly include correct DT includes
  tpm: Explicitly include correct DT includes
  lib/genalloc: Explicitly include correct DT includes
  parport: Explicitly include correct DT includes
  sbus: Explicitly include correct DT includes
  mux: Explicitly include correct DT includes
  macintosh: Explicitly include correct DT includes
  hte: Explicitly include correct DT includes
  EDAC: Explicitly include correct DT includes
  clocksource: Explicitly include correct DT includes
  sparc: Explicitly include correct DT includes
  riscv: Explicitly include correct DT includes

lib/genalloc: Explicitly include correct DT includes

2023-08-28T18:36:24+00:00

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it was merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Link: https://lore.kernel.org/r/20230714175056.4066297-1-robh@kernel.org
Signed-off-by: Rob Herring

misc/genalloc: Name subpools by of_node_full_name()

2023-07-26T07:45:01+00:00

A previous commit tried to come up with more generic subpool
names, but this isn't quite working: the node name was used
elsewhere to match pools to consumers which regressed the
nVidia Tegra 2/3 video decoder.

Revert back to an earlier approach using of_node_full_name()
instead of just the name to make sure the pool name is more
unique, and change both sites using this in the kernel.

It is not perfect since two SRAM nodes could have the same
subpool name but it makes the situation better than before.

Reported-by: Dmitry Osipenko 
Fixes: 21e5a2d10c8f ("misc: sram: Generate unique names for subpools")
Signed-off-by: Linus Walleij 
Tested-by: Dmitry Osipenko 
Link: https://lore.kernel.org/r/20230622074520.3058027-1-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman

lib/genalloc: use try_cmpxchg in {set,clear}_bits_ll

2023-02-03T06:50:05+00:00

Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in
{set,clear}_bits_ll.  x86 CMPXCHG instruction returns success in ZF flag,
so this change saves a compare after cmpxchg (and related move instruction
in front of cmpxchg).

Also, try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg
fails.

Note that the value from *ptr should be read using READ_ONCE to prevent
the compiler from merging, refetching or reordering the read.

The patch also declares these two functions inline, to ensure inlining.

No functional change intended.

Link: https://lkml.kernel.org/r/20230118150703.4024-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak 
Signed-off-by: Andrew Morton

all: replace find_next{,_zero}_bit with find_first{,_zero}_bit where appropriate

2022-01-15T16:47:31+00:00

find_first{,_zero}_bit is a more effective analogue of 'next' version if
start == 0. This patch replaces 'next' with 'first' where things look
trivial.

Signed-off-by: Yury Norov 
Tested-by: Wolfram Sang

lib/genalloc: add parameter description to fix doc compile warning

2021-05-07T02:24:12+00:00

Commit 52fbf1134d47 ("lib/genalloc.c: fix allocation of aligned buffer
from non-aligned chunk") added a new parameter 'start_addr' w/o
description for it. That causes some doc compile warning:

  lib/genalloc.c:649: warning: Function parameter or member 'start_addr' not described in 'gen_pool_first_fit'
  lib/genalloc.c:667: warning: Function parameter or member 'start_addr' not described in 'gen_pool_first_fit_align'
  lib/genalloc.c:694: warning: Function parameter or member 'start_addr' not described in 'gen_pool_fixed_alloc'
  lib/genalloc.c:729: warning: Function parameter or member 'start_addr' not described in 'gen_pool_first_fit_order_align'
  lib/genalloc.c:752: warning: Function parameter or member 'start_addr' not described in 'gen_pool_best_fit'

This fixes it by adding a parameter descriptions.

Link: https://lkml.kernel.org/r/20210405132021.131231-1-alexs@kernel.org
Signed-off-by: Alex Shi 
Cc: Alexey Skidanov 
Cc: Huang Shijie 
Cc: Alex Shi 
Cc: Bhaskar Chowdhury 
Cc: Stephen Rothwell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/genalloc.c: Fix a typo

2021-05-07T02:24:12+00:00

s/macthing/matching/

Link: https://lkml.kernel.org/r/20210326131530.30481-1-unixbhaskar@gmail.com
Signed-off-by: Bhaskar Chowdhury 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/genalloc.c: change return type to unsigned long for bitmap_set_ll

2021-02-26T17:41:04+00:00

Just as bitmap_clear_ll(), change return type to unsigned long
for bitmap_set_ll to avoid the possible overflow in future.

Link: https://lkml.kernel.org/r/20210105031644.2771-1-sjhuang@iluvatar.ai
Signed-off-by: Huang Shijie 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/genalloc: fix the overflow when size is too big

2020-12-29T23:36:49+00:00

Some graphic card has very big memory on chip, such as 32G bytes.

In the following case, it will cause overflow:

    pool = gen_pool_create(PAGE_SHIFT, NUMA_NO_NODE);
    ret = gen_pool_add(pool, 0x1000000, SZ_32G, NUMA_NO_NODE);

    va = gen_pool_alloc(pool, SZ_4G);

The overflow occurs in gen_pool_alloc_algo_owner():

		....
		size = nbits << order;
		....

The @nbits is "int" type, so it will overflow.
Then the gen_pool_avail() will return the wrong value.

This patch converts some "int" to "unsigned long", and
changes the compare code in while.

Link: https://lkml.kernel.org/r/20201229060657.3389-1-sjhuang@iluvatar.ai
Signed-off-by: Huang Shijie 
Reported-by: Shi Jiasheng 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds