From mboxrd@z Thu Jan 1 00:00:00 1970 From: vijay.kilari@gmail.com Subject: [PATCH v4 01/17] xen/arm: Add bitmap_find_next_zero_area helper function Date: Fri, 10 Jul 2015 13:12:36 +0530 Message-ID: <1436514172-3263-2-git-send-email-vijay.kilari@gmail.com> References: <1436514172-3263-1-git-send-email-vijay.kilari@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1436514172-3263-1-git-send-email-vijay.kilari@gmail.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Ian.Campbell@citrix.com, julien.grall@citrix.com, stefano.stabellini@eu.citrix.com, stefano.stabellini@citrix.com, tim@xen.org, xen-devel@lists.xen.org Cc: Keir Fraser , Ian Campbell , vijay.kilari@gmail.com, Prasun.Kapoor@caviumnetworks.com, Vijaya Kumar K , Ian Jackson , Jan Beulich , manish.jaggi@caviumnetworks.com List-Id: xen-devel@lists.xenproject.org From: Vijaya Kumar K bitmap_find_next_zero_area helper function will be used by physical ITS driver. This is imported from linux Signed-off-by: Vijaya Kumar K CC: Ian Campbell CC: Ian Jackson CC: Jan Beulich CC: Keir Fraser CC: Tim Deegan --- v4: Removed spaces and added tabs Moved ALIGN macro to lib.h v3: Moved changes to xen/common/bitmap.c and xen/include/xen/bitmap.h --- xen/common/bitmap.c | 37 +++++++++++++++++++++++++++++++++++++ xen/include/xen/bitmap.h | 5 +++++ xen/include/xen/lib.h | 2 ++ 3 files changed, 44 insertions(+) diff --git a/xen/common/bitmap.c b/xen/common/bitmap.c index 61d1ea4..77c68b0 100644 --- a/xen/common/bitmap.c +++ b/xen/common/bitmap.c @@ -489,6 +489,43 @@ int bitmap_allocate_region(unsigned long *bitmap, int pos, int order) } EXPORT_SYMBOL(bitmap_allocate_region); +/* + * bitmap_find_next_zero_area - find a contiguous aligned zero area + * @map: The address to base the search on + * @size: The bitmap size in bits + * @start: The bitnumber to start searching at + * @nr: The number of zeroed bits we're looking for + * @align_mask: Alignment mask for zero area + * + * The @align_mask should be one less than a power of 2; the effect is that + * the bit offset of all zero areas this function finds is multiples of that + * power of 2. A @align_mask of 0 means no alignment is required. + */ +unsigned long bitmap_find_next_zero_area(unsigned long *map, + unsigned long size, + unsigned long start, + unsigned int nr, + unsigned long align_mask) +{ + unsigned long index, end, i; +again: + index = find_next_zero_bit(map, size, start); + + /* Align allocation */ + index = ALIGN_MASK(index, align_mask); + + end = index + nr; + if (end > size) + return end; + i = find_next_bit(map, end, index); + if (i < end) { + start = i + 1; + goto again; + } + return index; +} +EXPORT_SYMBOL(bitmap_find_next_zero_area); + #ifdef __BIG_ENDIAN void bitmap_long_to_byte(uint8_t *bp, const unsigned long *lp, int nbits) diff --git a/xen/include/xen/bitmap.h b/xen/include/xen/bitmap.h index e2a3686..238b976 100644 --- a/xen/include/xen/bitmap.h +++ b/xen/include/xen/bitmap.h @@ -101,6 +101,11 @@ extern int bitmap_scnlistprintf(char *buf, unsigned int len, extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order); extern void bitmap_release_region(unsigned long *bitmap, int pos, int order); extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order); +extern unsigned long bitmap_find_next_zero_area(unsigned long *map, + unsigned long size, + unsigned long start, + unsigned int nr, + unsigned long align_mask); #define BITMAP_LAST_WORD_MASK(nbits) \ ( \ diff --git a/xen/include/xen/lib.h b/xen/include/xen/lib.h index 4258912..e7d9d95 100644 --- a/xen/include/xen/lib.h +++ b/xen/include/xen/lib.h @@ -55,6 +55,8 @@ #define ROUNDUP(x, a) (((x) + (a) - 1) & ~((a) - 1)) +#define ALIGN_MASK(x, mask) (((x) + (mask)) & ~(mask)) + #define reserve_bootmem(_p,_l) ((void)0) struct domain; -- 1.7.9.5