From 976e741c59b64d51fec0b8c4f5c1c8d3cf8ed3be Mon Sep 17 00:00:00 2001
From: Rik van Riel <riel@redhat.com>
Date: Thu, 12 Mar 2015 17:47:00 -0400
Subject: [PATCH 1/3] import __bitmap_parselist from Linux kernel
Import __bitmap_parselist from the Linux kernel, in order to parse
CPU ranges as used in eg. the kernel isolcpus= commandline argument.
This code appears to have been in the Linux kernel since the initial
git import in 2005, so I do not have attribution of which changeset(s)
introduced it into the kernel.
Signed-off-by: Rik van Riel <riel@redhat.com>
---
bitmap.c | 84 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
bitmap.h | 10 ++++++--
2 files changed, 92 insertions(+), 2 deletions(-)
diff --git a/bitmap.c b/bitmap.c
index 2f44660..6a7421a 100644
--- a/bitmap.c
+++ b/bitmap.c
@@ -377,3 +377,87 @@ int __bitmap_parse(const char *buf, unsigned int buflen,
return 0;
}
+
+/**
+ * __bitmap_parselist - convert list format ASCII string to bitmap
+ * @buf: read nul-terminated user string from this buffer
+ * @buflen: buffer size in bytes. If string is smaller than this
+ * then it must be terminated with a \0.
+ * @is_user: location of buffer, 0 indicates kernel space
+ * @maskp: write resulting mask here
+ * @nmaskbits: number of bits in mask to be written
+ *
+ * Input format is a comma-separated list of decimal numbers and
+ * ranges. Consecutively set bits are shown as two hyphen-separated
+ * decimal numbers, the smallest and largest bit numbers set in
+ * the range.
+ *
+ * Returns 0 on success, -errno on invalid input strings.
+ * Error values:
+ * %-EINVAL: second number in range smaller than first
+ * %-EINVAL: invalid character in string
+ * %-ERANGE: bit number specified too large for mask
+ */
+int __bitmap_parselist(const char *buf, unsigned int buflen,
+ int is_user __attribute((unused)), unsigned long *maskp,
+ int nmaskbits)
+{
+ int a, b, c, old_c, totaldigits;
+ int exp_digit, in_range;
+
+ totaldigits = c = 0;
+ bitmap_zero(maskp, nmaskbits);
+ do {
+ exp_digit = 1;
+ in_range = 0;
+ a = b = 0;
+
+ /* Get the next cpu# or a range of cpu#'s */
+ while (buflen) {
+ old_c = c;
+ c = *buf++;
+ buflen--;
+ 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 a cpu# or range */
+ if (c == '\0' || c == ',')
+ break;
+
+ if (c == '-') {
+ if (exp_digit || in_range)
+ return -EINVAL;
+ b = 0;
+ in_range = 1;
+ exp_digit = 1;
+ continue;
+ }
+
+ if (!isdigit(c))
+ return -EINVAL;
+
+ b = b * 10 + (c - '0');
+ if (!in_range)
+ a = b;
+ exp_digit = 0;
+ totaldigits++;
+ }
+ if (!(a <= b))
+ return -EINVAL;
+ if (b >= nmaskbits)
+ return -ERANGE;
+ while (a <= b) {
+ set_bit(a, maskp);
+ a++;
+ }
+ } while (buflen && c == ',');
+ return 0;
+}
diff --git a/bitmap.h b/bitmap.h
index 91ed499..7afce59 100644
--- a/bitmap.h
+++ b/bitmap.h
@@ -185,8 +185,8 @@ extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
unsigned long *dst, int nbits);
extern int bitmap_scnlistprintf(char *buf, unsigned int len,
const unsigned long *src, int nbits);
-extern int bitmap_parselist(const char *buf, unsigned long *maskp,
- int nmaskbits);
+extern int __bitmap_parselist(const char *buf, unsigned int buflen, int is_user,
+ unsigned long *dst, int nbits);
extern void bitmap_remap(unsigned long *dst, const unsigned long *src,
const unsigned long *old, const unsigned long *new, int bits);
extern int bitmap_bitremap(int oldbit,
@@ -351,6 +351,12 @@ static inline int bitmap_parse(const char *buf, unsigned int buflen,
return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
}
+static inline int bitmap_parselist(const char *buf, unsigned int buflen,
+ unsigned long *maskp, int nmaskbits)
+{
+ return __bitmap_parselist(buf, buflen, 0, maskp, nmaskbits);
+}
+
#endif /* __ASSEMBLY__ */
#endif /* __LINUX_BITMAP_H */
--
2.1.0