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authorLinus Torvalds <torvalds@linux-foundation.org>2021-09-01 08:44:42 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-09-01 08:44:42 -0700
commitc6c3c5704ba70820f6b632982abde06661b7222a (patch)
tree731e00452853789a90d9333508074e95ea1dc012 /lib
parentba1dc7f273c73b93e0e1dd9707b239ed69eebd70 (diff)
parent049d1693db78144c979b34e2084287ada912cf7f (diff)
downloadlinux-c6c3c5704ba70820f6b632982abde06661b7222a.tar.bz2
Merge tag 'driver-core-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH: "Here is the big set of driver core patches for 5.15-rc1. These do change a number of different things across different subsystems, and because of that, there were 2 stable tags created that might have already come into your tree from different pulls that did the following - changed the bus remove callback to return void - sysfs iomem_get_mapping rework Other than those two things, there's only a few small things in here: - kernfs performance improvements for huge numbers of sysfs users at once - tiny api cleanups - other minor changes All of these have been in linux-next for a while with no reported problems, other than the before-mentioned merge issue" * tag 'driver-core-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (33 commits) MAINTAINERS: Add dri-devel for component.[hc] driver core: platform: Remove platform_device_add_properties() ARM: tegra: paz00: Handle device properties with software node API bitmap: extend comment to bitmap_print_bitmask/list_to_buf drivers/base/node.c: use bin_attribute to break the size limitation of cpumap ABI topology: use bin_attribute to break the size limitation of cpumap ABI lib: test_bitmap: add bitmap_print_bitmask/list_to_buf test cases cpumask: introduce cpumap_print_list/bitmask_to_buf to support large bitmask and list sysfs: Rename struct bin_attribute member to f_mapping sysfs: Invoke iomem_get_mapping() from the sysfs open callback debugfs: Return error during {full/open}_proxy_open() on rmmod zorro: Drop useless (and hardly used) .driver member in struct zorro_dev zorro: Simplify remove callback sh: superhyway: Simplify check in remove callback nubus: Simplify check in remove callback nubus: Make struct nubus_driver::remove return void kernfs: dont call d_splice_alias() under kernfs node lock kernfs: use i_lock to protect concurrent inode updates kernfs: switch kernfs to use an rwsem kernfs: use VFS negative dentry caching ...
Diffstat (limited to 'lib')
-rw-r--r--lib/bitmap.c121
-rw-r--r--lib/test_bitmap.c150
2 files changed, 271 insertions, 0 deletions
diff --git a/lib/bitmap.c b/lib/bitmap.c
index 9401d39e4722..663dd81967d4 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -487,6 +487,127 @@ int bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp,
}
EXPORT_SYMBOL(bitmap_print_to_pagebuf);
+/**
+ * bitmap_print_to_buf - convert bitmap to list or hex format ASCII string
+ * @list: indicates whether the bitmap must be list
+ * true: print in decimal list format
+ * false: print in hexadecimal bitmask format
+ */
+static int bitmap_print_to_buf(bool list, char *buf, const unsigned long *maskp,
+ int nmaskbits, loff_t off, size_t count)
+{
+ const char *fmt = list ? "%*pbl\n" : "%*pb\n";
+ ssize_t size;
+ void *data;
+
+ data = kasprintf(GFP_KERNEL, fmt, nmaskbits, maskp);
+ if (!data)
+ return -ENOMEM;
+
+ size = memory_read_from_buffer(buf, count, &off, data, strlen(data) + 1);
+ kfree(data);
+
+ return size;
+}
+
+/**
+ * bitmap_print_bitmask_to_buf - convert bitmap to hex bitmask format ASCII string
+ *
+ * The bitmap_print_to_pagebuf() is used indirectly via its cpumap wrapper
+ * cpumap_print_to_pagebuf() or directly by drivers to export hexadecimal
+ * bitmask and decimal list to userspace by sysfs ABI.
+ * Drivers might be using a normal attribute for this kind of ABIs. A
+ * normal attribute typically has show entry as below:
+ * static ssize_t example_attribute_show(struct device *dev,
+ * struct device_attribute *attr, char *buf)
+ * {
+ * ...
+ * return bitmap_print_to_pagebuf(true, buf, &mask, nr_trig_max);
+ * }
+ * show entry of attribute has no offset and count parameters and this
+ * means the file is limited to one page only.
+ * bitmap_print_to_pagebuf() API works terribly well for this kind of
+ * normal attribute with buf parameter and without offset, count:
+ * bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp,
+ * int nmaskbits)
+ * {
+ * }
+ * The problem is once we have a large bitmap, we have a chance to get a
+ * bitmask or list more than one page. Especially for list, it could be
+ * as complex as 0,3,5,7,9,... We have no simple way to know it exact size.
+ * It turns out bin_attribute is a way to break this limit. bin_attribute
+ * has show entry as below:
+ * static ssize_t
+ * example_bin_attribute_show(struct file *filp, struct kobject *kobj,
+ * struct bin_attribute *attr, char *buf,
+ * loff_t offset, size_t count)
+ * {
+ * ...
+ * }
+ * With the new offset and count parameters, this makes sysfs ABI be able
+ * to support file size more than one page. For example, offset could be
+ * >= 4096.
+ * bitmap_print_bitmask_to_buf(), bitmap_print_list_to_buf() wit their
+ * cpumap wrapper cpumap_print_bitmask_to_buf(), cpumap_print_list_to_buf()
+ * make those drivers be able to support large bitmask and list after they
+ * move to use bin_attribute. In result, we have to pass the corresponding
+ * parameters such as off, count from bin_attribute show entry to this API.
+ *
+ * @buf: buffer into which string is placed
+ * @maskp: pointer to bitmap to convert
+ * @nmaskbits: size of bitmap, in bits
+ * @off: in the string from which we are copying, We copy to @buf
+ * @count: the maximum number of bytes to print
+ *
+ * The role of cpumap_print_bitmask_to_buf() and cpumap_print_list_to_buf()
+ * is similar with cpumap_print_to_pagebuf(), the difference is that
+ * bitmap_print_to_pagebuf() mainly serves sysfs attribute with the assumption
+ * the destination buffer is exactly one page and won't be more than one page.
+ * cpumap_print_bitmask_to_buf() and cpumap_print_list_to_buf(), on the other
+ * hand, mainly serves bin_attribute which doesn't work with exact one page,
+ * and it can break the size limit of converted decimal list and hexadecimal
+ * bitmask.
+ *
+ * WARNING!
+ *
+ * This function is not a replacement for sprintf() or bitmap_print_to_pagebuf().
+ * It is intended to workaround sysfs limitations discussed above and should be
+ * used carefully in general case for the following reasons:
+ * - Time complexity is O(nbits^2/count), comparing to O(nbits) for snprintf().
+ * - Memory complexity is O(nbits), comparing to O(1) for snprintf().
+ * - @off and @count are NOT offset and number of bits to print.
+ * - If printing part of bitmap as list, the resulting string is not a correct
+ * list representation of bitmap. Particularly, some bits within or out of
+ * related interval may be erroneously set or unset. The format of the string
+ * may be broken, so bitmap_parselist-like parser may fail parsing it.
+ * - If printing the whole bitmap as list by parts, user must ensure the order
+ * of calls of the function such that the offset is incremented linearly.
+ * - If printing the whole bitmap as list by parts, user must keep bitmap
+ * unchanged between the very first and very last call. Otherwise concatenated
+ * result may be incorrect, and format may be broken.
+ *
+ * Returns the number of characters actually printed to @buf
+ */
+int bitmap_print_bitmask_to_buf(char *buf, const unsigned long *maskp,
+ int nmaskbits, loff_t off, size_t count)
+{
+ return bitmap_print_to_buf(false, buf, maskp, nmaskbits, off, count);
+}
+EXPORT_SYMBOL(bitmap_print_bitmask_to_buf);
+
+/**
+ * bitmap_print_list_to_buf - convert bitmap to decimal list format ASCII string
+ *
+ * Everything is same with the above bitmap_print_bitmask_to_buf() except
+ * the print format.
+ */
+int bitmap_print_list_to_buf(char *buf, const unsigned long *maskp,
+ int nmaskbits, loff_t off, size_t count)
+{
+ return bitmap_print_to_buf(true, buf, maskp, nmaskbits, off, count);
+}
+EXPORT_SYMBOL(bitmap_print_list_to_buf);
+
/*
* Region 9-38:4/10 describes the following bitmap structure:
* 0 9 12 18 38 N
diff --git a/lib/test_bitmap.c b/lib/test_bitmap.c
index 4ea73f5aed41..d33fa5a61b95 100644
--- a/lib/test_bitmap.c
+++ b/lib/test_bitmap.c
@@ -19,6 +19,7 @@
KSTM_MODULE_GLOBALS();
static char pbl_buffer[PAGE_SIZE] __initdata;
+static char print_buf[PAGE_SIZE * 2] __initdata;
static const unsigned long exp1[] __initconst = {
BITMAP_FROM_U64(1),
@@ -156,6 +157,20 @@ static bool __init __check_eq_clump8(const char *srcfile, unsigned int line,
return true;
}
+static bool __init
+__check_eq_str(const char *srcfile, unsigned int line,
+ const char *exp_str, const char *str,
+ unsigned int len)
+{
+ bool eq;
+
+ eq = strncmp(exp_str, str, len) == 0;
+ if (!eq)
+ pr_err("[%s:%u] expected %s, got %s\n", srcfile, line, exp_str, str);
+
+ return eq;
+}
+
#define __expect_eq(suffix, ...) \
({ \
int result = 0; \
@@ -173,6 +188,7 @@ static bool __init __check_eq_clump8(const char *srcfile, unsigned int line,
#define expect_eq_pbl(...) __expect_eq(pbl, ##__VA_ARGS__)
#define expect_eq_u32_array(...) __expect_eq(u32_array, ##__VA_ARGS__)
#define expect_eq_clump8(...) __expect_eq(clump8, ##__VA_ARGS__)
+#define expect_eq_str(...) __expect_eq(str, ##__VA_ARGS__)
static void __init test_zero_clear(void)
{
@@ -660,6 +676,139 @@ static void __init test_bitmap_cut(void)
}
}
+struct test_bitmap_print {
+ const unsigned long *bitmap;
+ unsigned long nbits;
+ const char *mask;
+ const char *list;
+};
+
+static const unsigned long small_bitmap[] __initconst = {
+ BITMAP_FROM_U64(0x3333333311111111ULL),
+};
+
+static const char small_mask[] __initconst = "33333333,11111111\n";
+static const char small_list[] __initconst = "0,4,8,12,16,20,24,28,32-33,36-37,40-41,44-45,48-49,52-53,56-57,60-61\n";
+
+static const unsigned long large_bitmap[] __initconst = {
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+ BITMAP_FROM_U64(0x3333333311111111ULL), BITMAP_FROM_U64(0x3333333311111111ULL),
+};
+
+static const char large_mask[] __initconst = "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111,"
+ "33333333,11111111,33333333,11111111\n";
+
+static const char large_list[] __initconst = /* more than 4KB */
+ "0,4,8,12,16,20,24,28,32-33,36-37,40-41,44-45,48-49,52-53,56-57,60-61,64,68,72,76,80,84,88,92,96-97,100-101,104-1"
+ "05,108-109,112-113,116-117,120-121,124-125,128,132,136,140,144,148,152,156,160-161,164-165,168-169,172-173,176-1"
+ "77,180-181,184-185,188-189,192,196,200,204,208,212,216,220,224-225,228-229,232-233,236-237,240-241,244-245,248-2"
+ "49,252-253,256,260,264,268,272,276,280,284,288-289,292-293,296-297,300-301,304-305,308-309,312-313,316-317,320,3"
+ "24,328,332,336,340,344,348,352-353,356-357,360-361,364-365,368-369,372-373,376-377,380-381,384,388,392,396,400,4"
+ "04,408,412,416-417,420-421,424-425,428-429,432-433,436-437,440-441,444-445,448,452,456,460,464,468,472,476,480-4"
+ "81,484-485,488-489,492-493,496-497,500-501,504-505,508-509,512,516,520,524,528,532,536,540,544-545,548-549,552-5"
+ "53,556-557,560-561,564-565,568-569,572-573,576,580,584,588,592,596,600,604,608-609,612-613,616-617,620-621,624-6"
+ "25,628-629,632-633,636-637,640,644,648,652,656,660,664,668,672-673,676-677,680-681,684-685,688-689,692-693,696-6"
+ "97,700-701,704,708,712,716,720,724,728,732,736-737,740-741,744-745,748-749,752-753,756-757,760-761,764-765,768,7"
+ "72,776,780,784,788,792,796,800-801,804-805,808-809,812-813,816-817,820-821,824-825,828-829,832,836,840,844,848,8"
+ "52,856,860,864-865,868-869,872-873,876-877,880-881,884-885,888-889,892-893,896,900,904,908,912,916,920,924,928-9"
+ "29,932-933,936-937,940-941,944-945,948-949,952-953,956-957,960,964,968,972,976,980,984,988,992-993,996-997,1000-"
+ "1001,1004-1005,1008-1009,1012-1013,1016-1017,1020-1021,1024,1028,1032,1036,1040,1044,1048,1052,1056-1057,1060-10"
+ "61,1064-1065,1068-1069,1072-1073,1076-1077,1080-1081,1084-1085,1088,1092,1096,1100,1104,1108,1112,1116,1120-1121"
+ ",1124-1125,1128-1129,1132-1133,1136-1137,1140-1141,1144-1145,1148-1149,1152,1156,1160,1164,1168,1172,1176,1180,1"
+ "184-1185,1188-1189,1192-1193,1196-1197,1200-1201,1204-1205,1208-1209,1212-1213,1216,1220,1224,1228,1232,1236,124"
+ "0,1244,1248-1249,1252-1253,1256-1257,1260-1261,1264-1265,1268-1269,1272-1273,1276-1277,1280,1284,1288,1292,1296,"
+ "1300,1304,1308,1312-1313,1316-1317,1320-1321,1324-1325,1328-1329,1332-1333,1336-1337,1340-1341,1344,1348,1352,13"
+ "56,1360,1364,1368,1372,1376-1377,1380-1381,1384-1385,1388-1389,1392-1393,1396-1397,1400-1401,1404-1405,1408,1412"
+ ",1416,1420,1424,1428,1432,1436,1440-1441,1444-1445,1448-1449,1452-1453,1456-1457,1460-1461,1464-1465,1468-1469,1"
+ "472,1476,1480,1484,1488,1492,1496,1500,1504-1505,1508-1509,1512-1513,1516-1517,1520-1521,1524-1525,1528-1529,153"
+ "2-1533,1536,1540,1544,1548,1552,1556,1560,1564,1568-1569,1572-1573,1576-1577,1580-1581,1584-1585,1588-1589,1592-"
+ "1593,1596-1597,1600,1604,1608,1612,1616,1620,1624,1628,1632-1633,1636-1637,1640-1641,1644-1645,1648-1649,1652-16"
+ "53,1656-1657,1660-1661,1664,1668,1672,1676,1680,1684,1688,1692,1696-1697,1700-1701,1704-1705,1708-1709,1712-1713"
+ ",1716-1717,1720-1721,1724-1725,1728,1732,1736,1740,1744,1748,1752,1756,1760-1761,1764-1765,1768-1769,1772-1773,1"
+ "776-1777,1780-1781,1784-1785,1788-1789,1792,1796,1800,1804,1808,1812,1816,1820,1824-1825,1828-1829,1832-1833,183"
+ "6-1837,1840-1841,1844-1845,1848-1849,1852-1853,1856,1860,1864,1868,1872,1876,1880,1884,1888-1889,1892-1893,1896-"
+ "1897,1900-1901,1904-1905,1908-1909,1912-1913,1916-1917,1920,1924,1928,1932,1936,1940,1944,1948,1952-1953,1956-19"
+ "57,1960-1961,1964-1965,1968-1969,1972-1973,1976-1977,1980-1981,1984,1988,1992,1996,2000,2004,2008,2012,2016-2017"
+ ",2020-2021,2024-2025,2028-2029,2032-2033,2036-2037,2040-2041,2044-2045,2048,2052,2056,2060,2064,2068,2072,2076,2"
+ "080-2081,2084-2085,2088-2089,2092-2093,2096-2097,2100-2101,2104-2105,2108-2109,2112,2116,2120,2124,2128,2132,213"
+ "6,2140,2144-2145,2148-2149,2152-2153,2156-2157,2160-2161,2164-2165,2168-2169,2172-2173,2176,2180,2184,2188,2192,"
+ "2196,2200,2204,2208-2209,2212-2213,2216-2217,2220-2221,2224-2225,2228-2229,2232-2233,2236-2237,2240,2244,2248,22"
+ "52,2256,2260,2264,2268,2272-2273,2276-2277,2280-2281,2284-2285,2288-2289,2292-2293,2296-2297,2300-2301,2304,2308"
+ ",2312,2316,2320,2324,2328,2332,2336-2337,2340-2341,2344-2345,2348-2349,2352-2353,2356-2357,2360-2361,2364-2365,2"
+ "368,2372,2376,2380,2384,2388,2392,2396,2400-2401,2404-2405,2408-2409,2412-2413,2416-2417,2420-2421,2424-2425,242"
+ "8-2429,2432,2436,2440,2444,2448,2452,2456,2460,2464-2465,2468-2469,2472-2473,2476-2477,2480-2481,2484-2485,2488-"
+ "2489,2492-2493,2496,2500,2504,2508,2512,2516,2520,2524,2528-2529,2532-2533,2536-2537,2540-2541,2544-2545,2548-25"
+ "49,2552-2553,2556-2557\n";
+
+static const struct test_bitmap_print test_print[] __initconst = {
+ { small_bitmap, sizeof(small_bitmap) * BITS_PER_BYTE, small_mask, small_list },
+ { large_bitmap, sizeof(large_bitmap) * BITS_PER_BYTE, large_mask, large_list },
+};
+
+static void __init test_bitmap_print_buf(void)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(test_print); i++) {
+ const struct test_bitmap_print *t = &test_print[i];
+ int n;
+
+ n = bitmap_print_bitmask_to_buf(print_buf, t->bitmap, t->nbits,
+ 0, 2 * PAGE_SIZE);
+ expect_eq_uint(strlen(t->mask) + 1, n);
+ expect_eq_str(t->mask, print_buf, n);
+
+ n = bitmap_print_list_to_buf(print_buf, t->bitmap, t->nbits,
+ 0, 2 * PAGE_SIZE);
+ expect_eq_uint(strlen(t->list) + 1, n);
+ expect_eq_str(t->list, print_buf, n);
+
+ /* test by non-zero offset */
+ if (strlen(t->list) > PAGE_SIZE) {
+ n = bitmap_print_list_to_buf(print_buf, t->bitmap, t->nbits,
+ PAGE_SIZE, PAGE_SIZE);
+ expect_eq_uint(strlen(t->list) + 1 - PAGE_SIZE, n);
+ expect_eq_str(t->list + PAGE_SIZE, print_buf, n);
+ }
+ }
+}
+
static void __init selftest(void)
{
test_zero_clear();
@@ -672,6 +821,7 @@ static void __init selftest(void)
test_mem_optimisations();
test_for_each_set_clump8();
test_bitmap_cut();
+ test_bitmap_print_buf();
}
KSTM_MODULE_LOADERS(test_bitmap);