On Sun, 1 Jul 2018 at 01:49, Andy Shevchenko andriy.shevchenko@linux.intel.com wrote:

A lot of code become ugly because of open coding allocations for bitmaps.

Introduce three helpers to allow users be more clear of intention and keep their code neat.

Note, due to multiple circular dependencies we may not provide the helpers as inliners. For now we keep them exported and, perhaps, at some point in the future we will sort out header inclusion and inheritance.

Signed-off-by: Andy Shevchenko andriy.shevchenko@linux.intel.com

include/linux/bitmap.h | 8 ++++++++ lib/bitmap.c | 19 +++++++++++++++++++ 2 files changed, 27 insertions(+)

diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 1ee46f492267..acf5e8df3504 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -104,6 +104,14 @@

• contain all bit positions from 0 to 'bits' - 1.

*/

+/*

• • Allocation and deallocation of bitmap.
• • Provided in lib/bitmap.c to avoid circular dependency.
• */

+extern unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags); +extern unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags); +extern void bitmap_free(const unsigned long *bitmap);

/*

• lib/bitmap.c provides these functions:

*/ diff --git a/lib/bitmap.c b/lib/bitmap.c index 33e95cd359a2..09acf2fd6a35 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -13,6 +13,7 @@ #include <linux/bitops.h> #include <linux/bug.h> #include <linux/kernel.h> +#include <linux/slab.h> #include <linux/string.h> #include <linux/uaccess.h>

@@ -1125,6 +1126,24 @@ void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int n EXPORT_SYMBOL(bitmap_copy_le); #endif

+unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags) +{

•   return kmalloc_array(BITS_TO_LONGS(nbits), sizeof(unsigned long), flags);
  

+} +EXPORT_SYMBOL(bitmap_alloc);

+unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags) +{

•   return bitmap_alloc(nbits, flags | __GFP_ZERO);
  

+} +EXPORT_SYMBOL(bitmap_zalloc);

+void bitmap_free(const unsigned long *bitmap) +{

•   kfree(bitmap);
  

+} +EXPORT_SYMBOL(bitmap_free);

#if BITS_PER_LONG == 64 /**

• bitmap_from_arr32 - copy the contents of u32 array of bits to bitmap

stable-rc 4.14 build failed due to these build error,

lib/bitmap.c: In function 'bitmap_from_u32array': lib/bitmap.c:1133:1: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement] unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags) ^~~~~~~~ In file included from /srv/oe/build/tmp-lkft-glibc/work-shared/intel-corei7-64/kernel-source/lib/bitmap.c:8:0: lib/bitmap.c:1138:15: error: non-static declaration of 'bitmap_alloc' follows static declaration EXPORT_SYMBOL(bitmap_alloc); ^ include/linux/export.h:65:21: note: in definition of macro '___EXPORT_SYMBOL' extern typeof(sym) sym; \ ^~~ lib/bitmap.c:1138:1: note: in expansion of macro 'EXPORT_SYMBOL' EXPORT_SYMBOL(bitmap_alloc); ^~~~~~~~~~~~~ lib/bitmap.c:1133:16: note: previous definition of 'bitmap_alloc' was here unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags) ^~~~~~~~~~~~ In file included from /srv/oe/build/tmp-lkft-glibc/work-shared/intel-corei7-64/kernel-source/lib/bitmap.c:8:0: lib/bitmap.c:1144:15: error: non-static declaration of 'bitmap_zalloc' follows static declaration EXPORT_SYMBOL(bitmap_zalloc); ^ include/linux/export.h:65:21: note: in definition of macro '___EXPORT_SYMBOL' extern typeof(sym) sym; \ ^~~ lib/bitmap.c:1144:1: note: in expansion of macro 'EXPORT_SYMBOL' EXPORT_SYMBOL(bitmap_zalloc); ^~~~~~~~~~~~~ lib/bitmap.c:1140:16: note: previous definition of 'bitmap_zalloc' was here unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags) ^~~~~~~~~~~~~ In file included from /srv/oe/build/tmp-lkft-glibc/work-shared/intel-corei7-64/kernel-source/lib/bitmap.c:8:0: lib/bitmap.c:1150:15: error: non-static declaration of 'bitmap_free' follows static declaration EXPORT_SYMBOL(bitmap_free); ^ include/linux/export.h:65:21: note: in definition of macro '___EXPORT_SYMBOL' extern typeof(sym) sym; \ ^~~ lib/bitmap.c:1150:1: note: in expansion of macro 'EXPORT_SYMBOL' EXPORT_SYMBOL(bitmap_free); ^~~~~~~~~~~~~ lib/bitmap.c:1146:6: note: previous definition of 'bitmap_free' was here void bitmap_free(const unsigned long *bitmap) ^~~~~~~~~~~ CC drivers/char/random.o scripts/Makefile.build:326: recipe for target 'lib/bitmap.o' failed make[3]: *** [lib/bitmap.o] Error 1 Makefile:1052: recipe for target 'lib' failed make[2]: *** [lib] Error 2