Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

60 files changed, 15017 insertions, 0 deletions

diff --git a/lib/Kconfig b/lib/Kconfig
new file mode 100644
index 000000000000..eeb45225248f
--- /dev/null
+++ b/lib/Kconfig
@@ -0,0 +1,61 @@
+#
+# Library configuration
+#
+
+menu "Library routines"
+
+config CRC_CCITT
+	tristate "CRC-CCITT functions"
+	help
+	  This option is provided for the case where no in-kernel-tree
+	  modules require CRC-CCITT functions, but a module built outside
+	  the kernel tree does. Such modules that use library CRC-CCITT
+	  functions require M here.
+
+config CRC32
+	tristate "CRC32 functions"
+	default y
+	help
+	  This option is provided for the case where no in-kernel-tree
+	  modules require CRC32 functions, but a module built outside the
+	  kernel tree does. Such modules that use library CRC32 functions
+	  require M here.
+
+config LIBCRC32C
+	tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check"
+	help
+	  This option is provided for the case where no in-kernel-tree
+	  modules require CRC32c functions, but a module built outside the
+	  kernel tree does. Such modules that use library CRC32c functions
+	  require M here.  See Castagnoli93.
+	  Module will be libcrc32c.
+
+#
+# compression support is select'ed if needed
+#
+config ZLIB_INFLATE
+	tristate
+
+config ZLIB_DEFLATE
+	tristate
+
+#
+# reed solomon support is select'ed if needed
+#
+config REED_SOLOMON
+	tristate
+	
+config REED_SOLOMON_ENC8
+	boolean
+
+config REED_SOLOMON_DEC8
+	boolean
+
+config REED_SOLOMON_ENC16
+	boolean
+
+config REED_SOLOMON_DEC16
+	boolean
+
+endmenu
+
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
new file mode 100644
index 000000000000..426a0cf7b11c
--- /dev/null
+++ b/lib/Kconfig.debug
@@ -0,0 +1,159 @@
+
+config PRINTK_TIME
+	bool "Show timing information on printks"
+	help
+	  Selecting this option causes timing information to be
+	  included in printk output.  This allows you to measure
+	  the interval between kernel operations, including bootup
+	  operations.  This is useful for identifying long delays
+	  in kernel startup.
+
+
+config DEBUG_KERNEL
+	bool "Kernel debugging"
+	help
+	  Say Y here if you are developing drivers or trying to debug and
+	  identify kernel problems.
+
+config MAGIC_SYSRQ
+	bool "Magic SysRq key"
+	depends on DEBUG_KERNEL && !UML
+	help
+	  If you say Y here, you will have some control over the system even
+	  if the system crashes for example during kernel debugging (e.g., you
+	  will be able to flush the buffer cache to disk, reboot the system
+	  immediately or dump some status information). This is accomplished
+	  by pressing various keys while holding SysRq (Alt+PrintScreen). It
+	  also works on a serial console (on PC hardware at least), if you
+	  send a BREAK and then within 5 seconds a command keypress. The
+	  keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
+	  unless you really know what this hack does.
+
+config LOG_BUF_SHIFT
+	int "Kernel log buffer size (16 => 64KB, 17 => 128KB)" if DEBUG_KERNEL
+	range 12 21
+	default 17 if ARCH_S390
+	default 16 if X86_NUMAQ || IA64
+	default 15 if SMP
+	default 14
+	help
+	  Select kernel log buffer size as a power of 2.
+	  Defaults and Examples:
+	  	     17 => 128 KB for S/390
+		     16 => 64 KB for x86 NUMAQ or IA-64
+	             15 => 32 KB for SMP
+	             14 => 16 KB for uniprocessor
+		     13 =>  8 KB
+		     12 =>  4 KB
+
+config SCHEDSTATS
+	bool "Collect scheduler statistics"
+	depends on DEBUG_KERNEL && PROC_FS
+	help
+	  If you say Y here, additional code will be inserted into the
+	  scheduler and related routines to collect statistics about
+	  scheduler behavior and provide them in /proc/schedstat.  These
+	  stats may be useful for both tuning and debugging the scheduler
+	  If you aren't debugging the scheduler or trying to tune a specific
+	  application, you can say N to avoid the very slight overhead
+	  this adds.
+
+config DEBUG_SLAB
+	bool "Debug memory allocations"
+	depends on DEBUG_KERNEL
+	help
+	  Say Y here to have the kernel do limited verification on memory
+	  allocation as well as poisoning memory on free to catch use of freed
+	  memory. This can make kmalloc/kfree-intensive workloads much slower.
+
+config DEBUG_PREEMPT
+	bool "Debug preemptible kernel"
+	depends on DEBUG_KERNEL && PREEMPT
+	default y
+	help
+	  If you say Y here then the kernel will use a debug variant of the
+	  commonly used smp_processor_id() function and will print warnings
+	  if kernel code uses it in a preemption-unsafe way. Also, the kernel
+	  will detect preemption count underflows.
+
+config DEBUG_SPINLOCK
+	bool "Spinlock debugging"
+	depends on DEBUG_KERNEL
+	help
+	  Say Y here and build SMP to catch missing spinlock initialization
+	  and certain other kinds of spinlock errors commonly made.  This is
+	  best used in conjunction with the NMI watchdog so that spinlock
+	  deadlocks are also debuggable.
+
+config DEBUG_SPINLOCK_SLEEP
+	bool "Sleep-inside-spinlock checking"
+	depends on DEBUG_KERNEL
+	help
+	  If you say Y here, various routines which may sleep will become very
+	  noisy if they are called with a spinlock held.
+
+config DEBUG_KOBJECT
+	bool "kobject debugging"
+	depends on DEBUG_KERNEL
+	help
+	  If you say Y here, some extra kobject debugging messages will be sent
+	  to the syslog. 
+
+config DEBUG_HIGHMEM
+	bool "Highmem debugging"
+	depends on DEBUG_KERNEL && HIGHMEM
+	help
+	  This options enables addition error checking for high memory systems.
+	  Disable for production systems.
+
+config DEBUG_BUGVERBOSE
+	bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EMBEDDED
+	depends on ARM || ARM26 || M32R || M68K || SPARC32 || SPARC64 || (X86 && !X86_64) || FRV
+	default !EMBEDDED
+	help
+	  Say Y here to make BUG() panics output the file name and line number
+	  of the BUG call as well as the EIP and oops trace.  This aids
+	  debugging but costs about 70-100K of memory.
+
+config DEBUG_INFO
+	bool "Compile the kernel with debug info"
+	depends on DEBUG_KERNEL
+	help
+          If you say Y here the resulting kernel image will include
+	  debugging info resulting in a larger kernel image.
+	  Say Y here only if you plan to debug the kernel.
+
+	  If unsure, say N.
+
+config DEBUG_IOREMAP
+	bool "Enable ioremap() debugging"
+	depends on DEBUG_KERNEL && PARISC
+	help
+	  Enabling this option will cause the kernel to distinguish between
+	  ioremapped and physical addresses.  It will print a backtrace (at
+	  most one every 10 seconds), hopefully allowing you to see which
+	  drivers need work.  Fixing all these problems is a prerequisite
+	  for turning on USE_HPPA_IOREMAP.  The warnings are harmless;
+	  the kernel has enough information to fix the broken drivers
+	  automatically, but we'd like to make it more efficient by not
+	  having to do that.
+
+config DEBUG_FS
+	bool "Debug Filesystem"
+	depends on DEBUG_KERNEL
+	help
+	  debugfs is a virtual file system that kernel developers use to put
+	  debugging files into.  Enable this option to be able to read and
+	  write to these files.
+
+	  If unsure, say N.
+
+config FRAME_POINTER
+	bool "Compile the kernel with frame pointers"
+	depends on DEBUG_KERNEL && ((X86 && !X86_64) || CRIS || M68K || M68KNOMMU || FRV)
+	help
+	  If you say Y here the resulting kernel image will be slightly larger
+	  and slower, but it will give very useful debugging information.
+	  If you don't debug the kernel, you can say N, but we may not be able
+	  to solve problems without frame pointers.
+
diff --git a/lib/Makefile b/lib/Makefile
new file mode 100644
index 000000000000..7c70db79c0e0
--- /dev/null
+++ b/lib/Makefile
@@ -0,0 +1,45 @@
+#
+# Makefile for some libs needed in the kernel.
+#
+
+lib-y := errno.o ctype.o string.o vsprintf.o cmdline.o \
+	 bust_spinlocks.o rbtree.o radix-tree.o dump_stack.o \
+	 kobject.o kref.o idr.o div64.o int_sqrt.o \
+	 bitmap.o extable.o kobject_uevent.o prio_tree.o sha1.o \
+	 halfmd4.o
+
+obj-y += sort.o parser.o
+
+ifeq ($(CONFIG_DEBUG_KOBJECT),y)
+CFLAGS_kobject.o += -DDEBUG
+CFLAGS_kobject_uevent.o += -DDEBUG
+endif
+
+lib-$(CONFIG_RWSEM_GENERIC_SPINLOCK) += rwsem-spinlock.o
+lib-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem.o
+lib-$(CONFIG_GENERIC_FIND_NEXT_BIT) += find_next_bit.o
+obj-$(CONFIG_LOCK_KERNEL) += kernel_lock.o
+
+ifneq ($(CONFIG_HAVE_DEC_LOCK),y) 
+  lib-y += dec_and_lock.o
+endif
+
+obj-$(CONFIG_CRC_CCITT)	+= crc-ccitt.o
+obj-$(CONFIG_CRC32)	+= crc32.o
+obj-$(CONFIG_LIBCRC32C)	+= libcrc32c.o
+obj-$(CONFIG_GENERIC_IOMAP) += iomap.o
+
+obj-$(CONFIG_ZLIB_INFLATE) += zlib_inflate/
+obj-$(CONFIG_ZLIB_DEFLATE) += zlib_deflate/
+obj-$(CONFIG_REED_SOLOMON) += reed_solomon/
+
+hostprogs-y	:= gen_crc32table
+clean-files	:= crc32table.h
+
+$(obj)/crc32.o: $(obj)/crc32table.h
+
+quiet_cmd_crc32 = GEN     $@
+      cmd_crc32 = $< > $@
+
+$(obj)/crc32table.h: $(obj)/gen_crc32table
+	$(call cmd,crc32)
diff --git a/lib/bitmap.c b/lib/bitmap.c
new file mode 100644
index 000000000000..d1388a5ce89c
--- /dev/null
+++ b/lib/bitmap.c
@@ -0,0 +1,595 @@
+/*
+ * lib/bitmap.c
+ * Helper functions for bitmap.h.
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2.  See the file COPYING for more details.
+ */
+#include <linux/module.h>
+#include <linux/ctype.h>
+#include <linux/errno.h>
+#include <linux/bitmap.h>
+#include <linux/bitops.h>
+#include <asm/uaccess.h>
+
+/*
+ * bitmaps provide an array of bits, implemented using an an
+ * array of unsigned longs.  The number of valid bits in a
+ * given bitmap does _not_ need to be an exact multiple of
+ * BITS_PER_LONG.
+ *
+ * The possible unused bits in the last, partially used word
+ * of a bitmap are 'don't care'.  The implementation makes
+ * no particular effort to keep them zero.  It ensures that
+ * their value will not affect the results of any operation.
+ * The bitmap operations that return Boolean (bitmap_empty,
+ * for example) or scalar (bitmap_weight, for example) results
+ * carefully filter out these unused bits from impacting their
+ * results.
+ *
+ * These operations actually hold to a slightly stronger rule:
+ * if you don't input any bitmaps to these ops that have some
+ * unused bits set, then they won't output any set unused bits
+ * in output bitmaps.
+ *
+ * The byte ordering of bitmaps is more natural on little
+ * endian architectures.  See the big-endian headers
+ * include/asm-ppc64/bitops.h and include/asm-s390/bitops.h
+ * for the best explanations of this ordering.
+ */
+
+int __bitmap_empty(const unsigned long *bitmap, int bits)
+{
+	int k, lim = bits/BITS_PER_LONG;
+	for (k = 0; k < lim; ++k)
+		if (bitmap[k])
+			return 0;
+
+	if (bits % BITS_PER_LONG)
+		if (bitmap[k] & BITMAP_LAST_WORD_MASK(bits))
+			return 0;
+
+	return 1;
+}
+EXPORT_SYMBOL(__bitmap_empty);
+
+int __bitmap_full(const unsigned long *bitmap, int bits)
+{
+	int k, lim = bits/BITS_PER_LONG;
+	for (k = 0; k < lim; ++k)
+		if (~bitmap[k])
+			return 0;
+
+	if (bits % BITS_PER_LONG)
+		if (~bitmap[k] & BITMAP_LAST_WORD_MASK(bits))
+			return 0;
+
+	return 1;
+}
+EXPORT_SYMBOL(__bitmap_full);
+
+int __bitmap_equal(const unsigned long *bitmap1,
+		const unsigned long *bitmap2, int bits)
+{
+	int k, lim = bits/BITS_PER_LONG;
+	for (k = 0; k < lim; ++k)
+		if (bitmap1[k] != bitmap2[k])
+			return 0;
+
+	if (bits % BITS_PER_LONG)
+		if ((bitmap1[k] ^ bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits))
+			return 0;
+
+	return 1;
+}
+EXPORT_SYMBOL(__bitmap_equal);
+
+void __bitmap_complement(unsigned long *dst, const unsigned long *src, int bits)
+{
+	int k, lim = bits/BITS_PER_LONG;
+	for (k = 0; k < lim; ++k)
+		dst[k] = ~src[k];
+
+	if (bits % BITS_PER_LONG)
+		dst[k] = ~src[k] & BITMAP_LAST_WORD_MASK(bits);
+}
+EXPORT_SYMBOL(__bitmap_complement);
+
+/*
+ * __bitmap_shift_right - logical right shift of the bits in a bitmap
+ *   @dst - destination bitmap
+ *   @src - source bitmap
+ *   @nbits - shift by this many bits
+ *   @bits - bitmap size, in bits
+ *
+ * Shifting right (dividing) means moving bits in the MS -> LS bit
+ * direction.  Zeros are fed into the vacated MS positions and the
+ * LS bits shifted off the bottom are lost.
+ */
+void __bitmap_shift_right(unsigned long *dst,
+			const unsigned long *src, int shift, int bits)
+{
+	int k, lim = BITS_TO_LONGS(bits), left = bits % BITS_PER_LONG;
+	int off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG;
+	unsigned long mask = (1UL << left) - 1;
+	for (k = 0; off + k < lim; ++k) {
+		unsigned long upper, lower;
+
+		/*
+		 * If shift is not word aligned, take lower rem bits of
+		 * word above and make them the top rem bits of result.
+		 */
+		if (!rem || off + k + 1 >= lim)
+			upper = 0;
+		else {
+			upper = src[off + k + 1];
+			if (off + k + 1 == lim - 1 && left)
+				upper &= mask;
+		}
+		lower = src[off + k];
+		if (left && off + k == lim - 1)
+			lower &= mask;
+		dst[k] = upper << (BITS_PER_LONG - rem) | lower >> rem;
+		if (left && k == lim - 1)
+			dst[k] &= mask;
+	}
+	if (off)
+		memset(&dst[lim - off], 0, off*sizeof(unsigned long));
+}
+EXPORT_SYMBOL(__bitmap_shift_right);
+
+
+/*
+ * __bitmap_shift_left - logical left shift of the bits in a bitmap
+ *   @dst - destination bitmap
+ *   @src - source bitmap
+ *   @nbits - shift by this many bits
+ *   @bits - bitmap size, in bits
+ *
+ * Shifting left (multiplying) means moving bits in the LS -> MS
+ * direction.  Zeros are fed into the vacated LS bit positions
+ * and those MS bits shifted off the top are lost.
+ */
+
+void __bitmap_shift_left(unsigned long *dst,
+			const unsigned long *src, int shift, int bits)
+{
+	int k, lim = BITS_TO_LONGS(bits), left = bits % BITS_PER_LONG;
+	int off = shift/BITS_PER_LONG, rem = shift % BITS_PER_LONG;
+	for (k = lim - off - 1; k >= 0; --k) {
+		unsigned long upper, lower;
+
+		/*
+		 * If shift is not word aligned, take upper rem bits of
+		 * word below and make them the bottom rem bits of result.
+		 */
+		if (rem && k > 0)
+			lower = src[k - 1];
+		else
+			lower = 0;
+		upper = src[k];
+		if (left && k == lim - 1)
+			upper &= (1UL << left) - 1;
+		dst[k + off] = lower  >> (BITS_PER_LONG - rem) | upper << rem;
+		if (left && k + off == lim - 1)
+			dst[k + off] &= (1UL << left) - 1;
+	}
+	if (off)
+		memset(dst, 0, off*sizeof(unsigned long));
+}
+EXPORT_SYMBOL(__bitmap_shift_left);
+
+void __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
+				const unsigned long *bitmap2, int bits)
+{
+	int k;
+	int nr = BITS_TO_LONGS(bits);
+
+	for (k = 0; k < nr; k++)
+		dst[k] = bitmap1[k] & bitmap2[k];
+}
+EXPORT_SYMBOL(__bitmap_and);
+
+void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
+				const unsigned long *bitmap2, int bits)
+{
+	int k;
+	int nr = BITS_TO_LONGS(bits);
+
+	for (k = 0; k < nr; k++)
+		dst[k] = bitmap1[k] | bitmap2[k];
+}
+EXPORT_SYMBOL(__bitmap_or);
+
+void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
+				const unsigned long *bitmap2, int bits)
+{
+	int k;
+	int nr = BITS_TO_LONGS(bits);
+
+	for (k = 0; k < nr; k++)
+		dst[k] = bitmap1[k] ^ bitmap2[k];
+}
+EXPORT_SYMBOL(__bitmap_xor);
+
+void __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
+				const unsigned long *bitmap2, int bits)
+{
+	int k;
+	int nr = BITS_TO_LONGS(bits);
+
+	for (k = 0; k < nr; k++)
+		dst[k] = bitmap1[k] & ~bitmap2[k];
+}
+EXPORT_SYMBOL(__bitmap_andnot);
+
+int __bitmap_intersects(const unsigned long *bitmap1,
+				const unsigned long *bitmap2, int bits)
+{
+	int k, lim = bits/BITS_PER_LONG;
+	for (k = 0; k < lim; ++k)
+		if (bitmap1[k] & bitmap2[k])
+			return 1;
+
+	if (bits % BITS_PER_LONG)
+		if ((bitmap1[k] & bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits))
+			return 1;
+	return 0;
+}
+EXPORT_SYMBOL(__bitmap_intersects);
+
+int __bitmap_subset(const unsigned long *bitmap1,
+				const unsigned long *bitmap2, int bits)
+{
+	int k, lim = bits/BITS_PER_LONG;
+	for (k = 0; k < lim; ++k)
+		if (bitmap1[k] & ~bitmap2[k])
+			return 0;
+
+	if (bits % BITS_PER_LONG)
+		if ((bitmap1[k] & ~bitmap2[k]) & BITMAP_LAST_WORD_MASK(bits))
+			return 0;
+	return 1;
+}
+EXPORT_SYMBOL(__bitmap_subset);
+
+#if BITS_PER_LONG == 32
+int __bitmap_weight(const unsigned long *bitmap, int bits)
+{
+	int k, w = 0, lim = bits/BITS_PER_LONG;
+
+	for (k = 0; k < lim; k++)
+		w += hweight32(bitmap[k]);
+
+	if (bits % BITS_PER_LONG)
+		w += hweight32(bitmap[k] & BITMAP_LAST_WORD_MASK(bits));
+
+	return w;
+}
+#else
+int __bitmap_weight(const unsigned long *bitmap, int bits)
+{
+	int k, w = 0, lim = bits/BITS_PER_LONG;
+
+	for (k = 0; k < lim; k++)
+		w += hweight64(bitmap[k]);
+
+	if (bits % BITS_PER_LONG)
+		w += hweight64(bitmap[k] & BITMAP_LAST_WORD_MASK(bits));
+
+	return w;
+}
+#endif
+EXPORT_SYMBOL(__bitmap_weight);
+
+/*
+ * Bitmap printing & parsing functions: first version by Bill Irwin,
+ * second version by Paul Jackson, third by Joe Korty.
+ */
+
+#define CHUNKSZ				32
+#define nbits_to_hold_value(val)	fls(val)
+#define roundup_power2(val,modulus)	(((val) + (modulus) - 1) & ~((modulus) - 1))
+#define unhex(c)			(isdigit(c) ? (c - '0') : (toupper(c) - 'A' + 10))
+#define BASEDEC 10		/* fancier cpuset lists input in decimal */
+
+/**
+ * bitmap_scnprintf - convert bitmap to an ASCII hex string.
+ * @buf: byte buffer into which string is placed
+ * @buflen: reserved size of @buf, in bytes
+ * @maskp: pointer to bitmap to convert
+ * @nmaskbits: size of bitmap, in bits
+ *
+ * Exactly @nmaskbits bits are displayed.  Hex digits are grouped into
+ * comma-separated sets of eight digits per set.
+ */
+int bitmap_scnprintf(char *buf, unsigned int buflen,
+	const unsigned long *maskp, int nmaskbits)
+{
+	int i, word, bit, len = 0;
+	unsigned long val;
+	const char *sep = "";
+	int chunksz;
+	u32 chunkmask;
+
+	chunksz = nmaskbits & (CHUNKSZ - 1);
+	if (chunksz == 0)
+		chunksz = CHUNKSZ;
+
+	i = roundup_power2(nmaskbits, CHUNKSZ) - CHUNKSZ;
+	for (; i >= 0; i -= CHUNKSZ) {
+		chunkmask = ((1ULL << chunksz) - 1);
+		word = i / BITS_PER_LONG;
+		bit = i % BITS_PER_LONG;
+		val = (maskp[word] >> bit) & chunkmask;
+		len += scnprintf(buf+len, buflen-len, "%s%0*lx", sep,
+			(chunksz+3)/4, val);
+		chunksz = CHUNKSZ;
+		sep = ",";
+	}
+	return len;
+}
+EXPORT_SYMBOL(bitmap_scnprintf);
+
+/**
+ * bitmap_parse - convert an ASCII hex string into a bitmap.
+ * @buf: pointer to buffer in user space containing string.
+ * @buflen: buffer size in bytes.  If string is smaller than this
+ *    then it must be terminated with a \0.
+ * @maskp: pointer to bitmap array that will contain result.
+ * @nmaskbits: size of bitmap, in bits.
+ *
+ * Commas group hex digits into chunks.  Each chunk defines exactly 32
+ * bits of the resultant bitmask.  No chunk may specify a value larger
+ * than 32 bits (-EOVERFLOW), and if a chunk specifies a smaller value
+ * then leading 0-bits are prepended.  -EINVAL is returned for illegal
+ * characters and for grouping errors such as "1,,5", ",44", "," and "".
+ * Leading and trailing whitespace accepted, but not embedded whitespace.
+ */
+int bitmap_parse(const char __user *ubuf, unsigned int ubuflen,
+        unsigned long *maskp, int nmaskbits)
+{
+	int c, old_c, totaldigits, ndigits, nchunks, nbits;
+	u32 chunk;
+
+	bitmap_zero(maskp, nmaskbits);
+
+	nchunks = nbits = totaldigits = c = 0;
+	do {
+		chunk = ndigits = 0;
+
+		/* Get the next chunk of the bitmap */
+		while (ubuflen) {
+			old_c = c;
+			if (get_user(c, ubuf++))
+				return -EFAULT;
+			ubuflen--;
+			if (isspace(c))
+				continue;
+
+			/*
+			 * If the last character was a space and the current
+			 * character isn't '\0', we've got embedded whitespace.
+			 * This is a no-no, so throw an error.
+			 */
+			if (totaldigits && c && isspace(old_c))
+				return -EINVAL;
+
+			/* A '\0' or a ',' signal the end of the chunk */
+			if (c == '\0' || c == ',')
+				break;
+
+			if (!isxdigit(c))
+				return -EINVAL;
+
+			/*
+			 * Make sure there are at least 4 free bits in 'chunk'.
+			 * If not, this hexdigit will overflow 'chunk', so
+			 * throw an error.
+			 */
+			if (chunk & ~((1UL << (CHUNKSZ - 4)) - 1))
+				return -EOVERFLOW;
+
+			chunk = (chunk << 4) | unhex(c);
+			ndigits++; totaldigits++;
+		}
+		if (ndigits == 0)
+			return -EINVAL;
+		if (nchunks == 0 && chunk == 0)
+			continue;
+
+		__bitmap_shift_left(maskp, maskp, CHUNKSZ, nmaskbits);
+		*maskp |= c