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author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-09-01 08:44:42 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-09-01 08:44:42 -0700 |
commit | c6c3c5704ba70820f6b632982abde06661b7222a (patch) | |
tree | 731e00452853789a90d9333508074e95ea1dc012 /lib | |
parent | ba1dc7f273c73b93e0e1dd9707b239ed69eebd70 (diff) | |
parent | 049d1693db78144c979b34e2084287ada912cf7f (diff) | |
download | linux-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.c | 121 | ||||
-rw-r--r-- | lib/test_bitmap.c | 150 |
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); |