Merge branch 'akpm' (patches from Andrew)

Merge more updates from Andrew Morton:
 "Most of the rest of MM and various other things. Some Kconfig rework
  still awaits merges of dependent trees from linux-next.

  Subsystems affected by this patch series: mm/hotfixes, mm/memcg,
  mm/vmstat, mm/thp, procfs, sysctl, misc, notifiers, core-kernel,
  bitops, lib, checkpatch, epoll, binfmt, init, rapidio, uaccess, kcov,
  ubsan, ipc, bitmap, mm/pagemap"

* akpm: (86 commits)
  mm: remove __ARCH_HAS_4LEVEL_HACK and include/asm-generic/4level-fixup.h
  um: add support for folded p4d page tables
  um: remove unused pxx_offset_proc() and addr_pte() functions
  sparc32: use pgtable-nopud instead of 4level-fixup
  parisc/hugetlb: use pgtable-nopXd instead of 4level-fixup
  parisc: use pgtable-nopXd instead of 4level-fixup
  nds32: use pgtable-nopmd instead of 4level-fixup
  microblaze: use pgtable-nopmd instead of 4level-fixup
  m68k: mm: use pgtable-nopXd instead of 4level-fixup
  m68k: nommu: use pgtable-nopud instead of 4level-fixup
  c6x: use pgtable-nopud instead of 4level-fixup
  arm: nommu: use pgtable-nopud instead of 4level-fixup
  alpha: use pgtable-nopud instead of 4level-fixup
  gpio: pca953x: tighten up indentation
  gpio: pca953x: convert to use bitmap API
  gpio: pca953x: use input from regs structure in pca953x_irq_pending()
  gpio: pca953x: remove redundant variable and check in IRQ handler
  lib/bitmap: introduce bitmap_replace() helper
  lib/test_bitmap: fix comment about this file
  lib/test_bitmap: move exp1 and exp2 upper for others to use
  ...

1 files changed, 51 insertions, 0 deletions

diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index 29fc933df3bf..ff335b22f23c 100644
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -53,6 +53,7 @@
  *  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_replace(dst, old, new, mask, nbits)  *dst = (*old & ~(*mask)) | (*new & *mask)
  *  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
@@ -66,6 +67,8 @@
  *  bitmap_allocate_region(bitmap, pos, order)  Allocate specified bit region
  *  bitmap_from_arr32(dst, buf, nbits)          Copy nbits from u32[] buf to dst
  *  bitmap_to_arr32(buf, src, nbits)            Copy nbits from buf to u32[] dst
+ *  bitmap_get_value8(map, start)               Get 8bit value from map at start
+ *  bitmap_set_value8(map, value, start)        Set 8bit value to map at start
  *
  * Note, bitmap_zero() and bitmap_fill() operate over the region of
  * unsigned longs, that is, bits behind bitmap till the unsigned long
@@ -138,6 +141,9 @@ extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
 			const unsigned long *bitmap2, unsigned int nbits);
 extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
 			const unsigned long *bitmap2, unsigned int nbits);
+extern void __bitmap_replace(unsigned long *dst,
+			const unsigned long *old, const unsigned long *new,
+			const unsigned long *mask, unsigned int nbits);
 extern int __bitmap_intersects(const unsigned long *bitmap1,
 			const unsigned long *bitmap2, unsigned int nbits);
 extern int __bitmap_subset(const unsigned long *bitmap1,
@@ -432,6 +438,18 @@ static inline void bitmap_shift_left(unsigned long *dst, const unsigned long *sr
 		__bitmap_shift_left(dst, src, shift, nbits);
 }
 
+static inline void bitmap_replace(unsigned long *dst,
+				  const unsigned long *old,
+				  const unsigned long *new,
+				  const unsigned long *mask,
+				  unsigned int nbits)
+{
+	if (small_const_nbits(nbits))
+		*dst = (*old & ~(*mask)) | (*new & *mask);
+	else
+		__bitmap_replace(dst, old, new, mask, nbits);
+}
+
 static inline int bitmap_parse(const char *buf, unsigned int buflen,
 			unsigned long *maskp, int nmaskbits)
 {
@@ -489,6 +507,39 @@ static inline void bitmap_from_u64(unsigned long *dst, u64 mask)
 		dst[1] = mask >> 32;
 }
 
+/**
+ * bitmap_get_value8 - get an 8-bit value within a memory region
+ * @map: address to the bitmap memory region
+ * @start: bit offset of the 8-bit value; must be a multiple of 8
+ *
+ * Returns the 8-bit value located at the @start bit offset within the @src
+ * memory region.
+ */
+static inline unsigned long bitmap_get_value8(const unsigned long *map,
+					      unsigned long start)
+{
+	const size_t index = BIT_WORD(start);
+	const unsigned long offset = start % BITS_PER_LONG;
+
+	return (map[index] >> offset) & 0xFF;
+}
+
+/**
+ * bitmap_set_value8 - set an 8-bit value within a memory region
+ * @map: address to the bitmap memory region
+ * @value: the 8-bit value; values wider than 8 bits may clobber bitmap
+ * @start: bit offset of the 8-bit value; must be a multiple of 8
+ */
+static inline void bitmap_set_value8(unsigned long *map, unsigned long value,
+				     unsigned long start)
+{
+	const size_t index = BIT_WORD(start);
+	const unsigned long offset = start % BITS_PER_LONG;
+
+	map[index] &= ~(0xFFUL << offset);
+	map[index] |= value << offset;
+}
+
 #endif /* __ASSEMBLY__ */
 
 #endif /* __LINUX_BITMAP_H */