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authorRandy Dunlap <rdunlap@infradead.org>2017-10-16 16:32:51 -0700
committerJonathan Corbet <corbet@lwn.net>2017-10-19 13:01:40 -0600
commit7d7363e403ce959941f80684cc5f33e747afff17 (patch)
tree793fe05bf0426d400b07b3077b8d521a93ea96f4 /include
parent718d50ec782caad13e0cc78fa6a76ff2226f3dd3 (diff)
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documentation: kernel-api: add more info on bitmap functions
There are some good comments about bitmap operations in lib/bitmap.c and include/linux/bitmap.h, so format them for document generation and pull them into core-api/kernel-api.rst. I converted the "tables" of functions from using tabs to using spaces so that they are more readable in the source file and in the generated output. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Diffstat (limited to 'include')
-rw-r--r--include/linux/bitmap.h105
1 files changed, 57 insertions, 48 deletions
diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index 5c4178016b1e..d9974c7a0a61 100644
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -21,65 +21,74 @@
* See lib/bitmap.c for more details.
*/
-/*
+/**
+ * DOC: bitmap overview
+ *
* The available bitmap operations and their rough meaning in the
* case that the bitmap is a single unsigned long are thus:
*
* Note that nbits should be always a compile time evaluable constant.
* Otherwise many inlines will generate horrible code.
*
- * bitmap_zero(dst, nbits) *dst = 0UL
- * bitmap_fill(dst, nbits) *dst = ~0UL
- * bitmap_copy(dst, src, nbits) *dst = *src
- * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2
- * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2
- * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2
- * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2)
- * bitmap_complement(dst, src, nbits) *dst = ~(*src)
- * bitmap_equal(src1, src2, nbits) Are *src1 and *src2 equal?
- * bitmap_intersects(src1, src2, nbits) Do *src1 and *src2 overlap?
- * bitmap_subset(src1, src2, nbits) Is *src1 a subset of *src2?
- * bitmap_empty(src, nbits) Are all bits zero in *src?
- * bitmap_full(src, nbits) Are all bits set in *src?
- * bitmap_weight(src, nbits) Hamming Weight: number set bits
- * bitmap_set(dst, pos, nbits) Set specified bit area
- * bitmap_clear(dst, pos, nbits) Clear specified bit area
- * bitmap_find_next_zero_area(buf, len, pos, n, mask) Find bit free area
- * bitmap_find_next_zero_area_off(buf, len, pos, n, mask) as above
- * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n
- * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n
- * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src)
- * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit)
- * bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap
- * bitmap_fold(dst, orig, sz, nbits) dst bits = orig bits mod sz
- * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf
- * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf
- * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from kernel buf
- * bitmap_parselist_user(buf, dst, nbits) Parse bitmap dst from user buf
- * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region
- * bitmap_release_region(bitmap, pos, order) Free specified bit region
- * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
- * bitmap_from_u32array(dst, nbits, buf, nwords) *dst = *buf (nwords 32b words)
- * bitmap_to_u32array(buf, nwords, src, nbits) *buf = *dst (nwords 32b words)
+ * ::
+ *
+ * bitmap_zero(dst, nbits) *dst = 0UL
+ * bitmap_fill(dst, nbits) *dst = ~0UL
+ * bitmap_copy(dst, src, nbits) *dst = *src
+ * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2
+ * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2
+ * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2
+ * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2)
+ * bitmap_complement(dst, src, nbits) *dst = ~(*src)
+ * bitmap_equal(src1, src2, nbits) Are *src1 and *src2 equal?
+ * bitmap_intersects(src1, src2, nbits) Do *src1 and *src2 overlap?
+ * bitmap_subset(src1, src2, nbits) Is *src1 a subset of *src2?
+ * bitmap_empty(src, nbits) Are all bits zero in *src?
+ * bitmap_full(src, nbits) Are all bits set in *src?
+ * bitmap_weight(src, nbits) Hamming Weight: number set bits
+ * bitmap_set(dst, pos, nbits) Set specified bit area
+ * bitmap_clear(dst, pos, nbits) Clear specified bit area
+ * bitmap_find_next_zero_area(buf, len, pos, n, mask) Find bit free area
+ * bitmap_find_next_zero_area_off(buf, len, pos, n, mask) as above
+ * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n
+ * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n
+ * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src)
+ * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit)
+ * bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap
+ * bitmap_fold(dst, orig, sz, nbits) dst bits = orig bits mod sz
+ * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf
+ * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf
+ * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from kernel buf
+ * bitmap_parselist_user(buf, dst, nbits) Parse bitmap dst from user buf
+ * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region
+ * bitmap_release_region(bitmap, pos, order) Free specified bit region
+ * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
+ * bitmap_from_u32array(dst, nbits, buf, nwords) *dst = *buf (nwords 32b words)
+ * bitmap_to_u32array(buf, nwords, src, nbits) *buf = *dst (nwords 32b words)
+ *
*/
-/*
- * Also the following operations in asm/bitops.h apply to bitmaps.
+/**
+ * DOC: bitmap bitops
+ *
+ * Also the following operations in asm/bitops.h apply to bitmaps.::
+ *
+ * set_bit(bit, addr) *addr |= bit
+ * clear_bit(bit, addr) *addr &= ~bit
+ * change_bit(bit, addr) *addr ^= bit
+ * test_bit(bit, addr) Is bit set in *addr?
+ * test_and_set_bit(bit, addr) Set bit and return old value
+ * test_and_clear_bit(bit, addr) Clear bit and return old value
+ * test_and_change_bit(bit, addr) Change bit and return old value
+ * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
+ * find_first_bit(addr, nbits) Position first set bit in *addr
+ * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit
+ * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
*
- * set_bit(bit, addr) *addr |= bit
- * clear_bit(bit, addr) *addr &= ~bit
- * change_bit(bit, addr) *addr ^= bit
- * test_bit(bit, addr) Is bit set in *addr?
- * test_and_set_bit(bit, addr) Set bit and return old value
- * test_and_clear_bit(bit, addr) Clear bit and return old value
- * test_and_change_bit(bit, addr) Change bit and return old value
- * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
- * find_first_bit(addr, nbits) Position first set bit in *addr
- * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit
- * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
*/
-/*
+/**
+ * DOC: declare bitmap
* The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
* to declare an array named 'name' of just enough unsigned longs to
* contain all bit positions from 0 to 'bits' - 1.