diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/bitmap.c | 193 | ||||
| -rw-r--r-- | lib/string.c | 17 | ||||
| -rw-r--r-- | lib/test_bitmap.c | 105 |
3 files changed, 212 insertions, 103 deletions
diff --git a/lib/bitmap.c b/lib/bitmap.c index 6e175fbd69a9..89260aa342d6 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -431,97 +431,6 @@ EXPORT_SYMBOL(bitmap_find_next_zero_area_off); * second version by Paul Jackson, third by Joe Korty. */ -#define CHUNKSZ 32 -#define nbits_to_hold_value(val) fls(val) -#define BASEDEC 10 /* fancier cpuset lists input in decimal */ - -/** - * __bitmap_parse - convert an ASCII hex string into a bitmap. - * @buf: pointer to buffer containing string. - * @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: 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 *buf, unsigned int buflen, - int is_user, unsigned long *maskp, - int nmaskbits) -{ - int c, old_c, totaldigits, ndigits, nchunks, nbits; - u32 chunk; - const char __user __force *ubuf = (const char __user __force *)buf; - - bitmap_zero(maskp, nmaskbits); - - nchunks = nbits = totaldigits = c = 0; - do { - chunk = 0; - ndigits = totaldigits; - - /* Get the next chunk of the bitmap */ - while (buflen) { - old_c = c; - if (is_user) { - if (__get_user(c, ubuf++)) - return -EFAULT; - } - else - 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 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) | hex_to_bin(c); - totaldigits++; - } - if (ndigits == totaldigits) - return -EINVAL; - if (nchunks == 0 && chunk == 0) - continue; - - __bitmap_shift_left(maskp, maskp, CHUNKSZ, nmaskbits); - *maskp |= chunk; - nchunks++; - nbits += (nchunks == 1) ? nbits_to_hold_value(chunk) : CHUNKSZ; - if (nbits > nmaskbits) - return -EOVERFLOW; - } while (buflen && c == ','); - - return 0; -} -EXPORT_SYMBOL(__bitmap_parse); - /** * bitmap_parse_user - convert an ASCII hex string in a user buffer into a bitmap * @@ -530,22 +439,22 @@ EXPORT_SYMBOL(__bitmap_parse); * then it must be terminated with a \0. * @maskp: pointer to bitmap array that will contain result. * @nmaskbits: size of bitmap, in bits. - * - * Wrapper for __bitmap_parse(), providing it with user buffer. - * - * We cannot have this as an inline function in bitmap.h because it needs - * linux/uaccess.h to get the access_ok() declaration and this causes - * cyclic dependencies. */ int bitmap_parse_user(const char __user *ubuf, unsigned int ulen, unsigned long *maskp, int nmaskbits) { - if (!access_ok(ubuf, ulen)) - return -EFAULT; - return __bitmap_parse((const char __force *)ubuf, - ulen, 1, maskp, nmaskbits); + char *buf; + int ret; + buf = memdup_user_nul(ubuf, ulen); + if (IS_ERR(buf)) + return PTR_ERR(buf); + + ret = bitmap_parse(buf, UINT_MAX, maskp, nmaskbits); + + kfree(buf); + return ret; } EXPORT_SYMBOL(bitmap_parse_user); @@ -653,6 +562,14 @@ static const char *bitmap_find_region(const char *str) return end_of_str(*str) ? NULL : str; } +static const char *bitmap_find_region_reverse(const char *start, const char *end) +{ + while (start <= end && __end_of_region(*end)) + end--; + + return end; +} + static const char *bitmap_parse_region(const char *str, struct region *r) { str = bitmap_getnum(str, &r->start); @@ -776,6 +693,80 @@ int bitmap_parselist_user(const char __user *ubuf, } EXPORT_SYMBOL(bitmap_parselist_user); +static const char *bitmap_get_x32_reverse(const char *start, + const char *end, u32 *num) +{ + u32 ret = 0; + int c, i; + + for (i = 0; i < 32; i += 4) { + c = hex_to_bin(*end--); + if (c < 0) + return ERR_PTR(-EINVAL); + + ret |= c << i; + + if (start > end || __end_of_region(*end)) + goto out; + } + + if (hex_to_bin(*end--) >= 0) + return ERR_PTR(-EOVERFLOW); +out: + *num = ret; + return end; +} + +/** + * bitmap_parse - convert an ASCII hex string into a bitmap. + * @start: pointer to buffer containing string. + * @buflen: buffer size in bytes. If string is smaller than this + * then it must be terminated with a \0 or \n. In that case, + * UINT_MAX may be provided instead of string length. + * @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. Grouping such as "1,,5", ",44", "," or "" is allowed. + * Leading, embedded and trailing whitespace accepted. + */ +int bitmap_parse(const char *start, unsigned int buflen, + unsigned long *maskp, int nmaskbits) +{ + const char *end = strnchrnul(start, buflen, '\n') - 1; + int chunks = BITS_TO_U32(nmaskbits); + u32 *bitmap = (u32 *)maskp; + int unset_bit; + + while (1) { + end = bitmap_find_region_reverse(start, end); + if (start > end) + break; + + if (!chunks--) + return -EOVERFLOW; + + end = bitmap_get_x32_reverse(start, end, bitmap++); + if (IS_ERR(end)) + return PTR_ERR(end); + } + + unset_bit = (BITS_TO_U32(nmaskbits) - chunks) * 32; + if (unset_bit < nmaskbits) { + bitmap_clear(maskp, unset_bit, nmaskbits - unset_bit); + return 0; + } + + if (find_next_bit(maskp, unset_bit, nmaskbits) != unset_bit) + return -EOVERFLOW; + + return 0; +} +EXPORT_SYMBOL(bitmap_parse); + #ifdef CONFIG_NUMA /** diff --git a/lib/string.c b/lib/string.c index 08ec58cc673b..f607b967d978 100644 --- a/lib/string.c +++ b/lib/string.c @@ -434,6 +434,23 @@ char *strchrnul(const char *s, int c) EXPORT_SYMBOL(strchrnul); #endif +/** + * strnchrnul - Find and return a character in a length limited string, + * or end of string + * @s: The string to be searched + * @count: The number of characters to be searched + * @c: The character to search for + * + * Returns pointer to the first occurrence of 'c' in s. If c is not found, + * then return a pointer to the last character of the string. + */ +char *strnchrnul(const char *s, size_t count, int c) +{ + while (count-- && *s && *s != (char)c) + s++; + return (char *)s; +} + #ifndef __HAVE_ARCH_STRRCHR /** * strrchr - Find the last occurrence of a character in a string diff --git a/lib/test_bitmap.c b/lib/test_bitmap.c index 71ec3afe1681..61ed71c1daba 100644 --- a/lib/test_bitmap.c +++ b/lib/test_bitmap.c @@ -295,7 +295,8 @@ static void __init test_replace(void) expect_eq_bitmap(bmap, exp3_1_0, nbits); } -#define PARSE_TIME 0x1 +#define PARSE_TIME 0x1 +#define NO_LEN 0x2 struct test_bitmap_parselist{ const int errno; @@ -349,7 +350,6 @@ static const struct test_bitmap_parselist parselist_tests[] __initconst = { {-EINVAL, "0-31:a/1", NULL, 8, 0}, {-EINVAL, "0-\n", NULL, 8, 0}, -#undef step }; static void __init __test_bitmap_parselist(int is_user) @@ -401,6 +401,95 @@ static void __init __test_bitmap_parselist(int is_user) } } +static const unsigned long parse_test[] __initconst = { + BITMAP_FROM_U64(0), + BITMAP_FROM_U64(1), + BITMAP_FROM_U64(0xdeadbeef), + BITMAP_FROM_U64(0x100000000ULL), +}; + +static const unsigned long parse_test2[] __initconst = { + BITMAP_FROM_U64(0x100000000ULL), BITMAP_FROM_U64(0xdeadbeef), + BITMAP_FROM_U64(0x100000000ULL), BITMAP_FROM_U64(0xbaadf00ddeadbeef), + BITMAP_FROM_U64(0x100000000ULL), BITMAP_FROM_U64(0x0badf00ddeadbeef), +}; + +static const struct test_bitmap_parselist parse_tests[] __initconst = { + {0, "", &parse_test[0 * step], 32, 0}, + {0, " ", &parse_test[0 * step], 32, 0}, + {0, "0", &parse_test[0 * step], 32, 0}, + {0, "0\n", &parse_test[0 * step], 32, 0}, + {0, "1", &parse_test[1 * step], 32, 0}, + {0, "deadbeef", &parse_test[2 * step], 32, 0}, + {0, "1,0", &parse_test[3 * step], 33, 0}, + {0, "deadbeef,\n,0,1", &parse_test[2 * step], 96, 0}, + + {0, "deadbeef,1,0", &parse_test2[0 * 2 * step], 96, 0}, + {0, "baadf00d,deadbeef,1,0", &parse_test2[1 * 2 * step], 128, 0}, + {0, "badf00d,deadbeef,1,0", &parse_test2[2 * 2 * step], 124, 0}, + {0, "badf00d,deadbeef,1,0", &parse_test2[2 * 2 * step], 124, NO_LEN}, + {0, " badf00d,deadbeef,1,0 ", &parse_test2[2 * 2 * step], 124, 0}, + {0, " , badf00d,deadbeef,1,0 , ", &parse_test2[2 * 2 * step], 124, 0}, + {0, " , badf00d, ,, ,,deadbeef,1,0 , ", &parse_test2[2 * 2 * step], 124, 0}, + + {-EINVAL, "goodfood,deadbeef,1,0", NULL, 128, 0}, + {-EOVERFLOW, "3,0", NULL, 33, 0}, + {-EOVERFLOW, "123badf00d,deadbeef,1,0", NULL, 128, 0}, + {-EOVERFLOW, "badf00d,deadbeef,1,0", NULL, 90, 0}, + {-EOVERFLOW, "fbadf00d,deadbeef,1,0", NULL, 95, 0}, + {-EOVERFLOW, "badf00d,deadbeef,1,0", NULL, 100, 0}, +#undef step +}; + +static void __init __test_bitmap_parse(int is_user) +{ + int i; + int err; + ktime_t time; + DECLARE_BITMAP(bmap, 2048); + char *mode = is_user ? "_user" : ""; + + for (i = 0; i < ARRAY_SIZE(parse_tests); i++) { + struct test_bitmap_parselist test = parse_tests[i]; + + if (is_user) { + size_t len = strlen(test.in); + mm_segment_t orig_fs = get_fs(); + + set_fs(KERNEL_DS); + time = ktime_get(); + err = bitmap_parse_user((__force const char __user *)test.in, len, + bmap, test.nbits); + time = ktime_get() - time; + set_fs(orig_fs); + } else { + size_t len = test.flags & NO_LEN ? + UINT_MAX : strlen(test.in); + time = ktime_get(); + err = bitmap_parse(test.in, len, bmap, test.nbits); + time = ktime_get() - time; + } + + if (err != test.errno) { + pr_err("parse%s: %d: input is %s, errno is %d, expected %d\n", + mode, i, test.in, err, test.errno); + continue; + } + + if (!err && test.expected + && !__bitmap_equal(bmap, test.expected, test.nbits)) { + pr_err("parse%s: %d: input is %s, result is 0x%lx, expected 0x%lx\n", + mode, i, test.in, bmap[0], + *test.expected); + continue; + } + + if (test.flags & PARSE_TIME) + pr_err("parse%s: %d: input is '%s' OK, Time: %llu\n", + mode, i, test.in, time); + } +} + static void __init test_bitmap_parselist(void) { __test_bitmap_parselist(0); @@ -411,6 +500,16 @@ static void __init test_bitmap_parselist_user(void) __test_bitmap_parselist(1); } +static void __init test_bitmap_parse(void) +{ + __test_bitmap_parse(0); +} + +static void __init test_bitmap_parse_user(void) +{ + __test_bitmap_parse(1); +} + #define EXP1_IN_BITS (sizeof(exp1) * 8) static void __init test_bitmap_arr32(void) @@ -516,6 +615,8 @@ static void __init selftest(void) test_copy(); test_replace(); test_bitmap_arr32(); + test_bitmap_parse(); + test_bitmap_parse_user(); test_bitmap_parselist(); test_bitmap_parselist_user(); test_mem_optimisations(); |