From 849369d6c66d3054688672f97d31fceb8e8230fb Mon Sep 17 00:00:00 2001 From: root Date: Fri, 25 Dec 2015 04:40:36 +0000 Subject: initial_commit --- Documentation/ia64/aliasing-test.c | 262 +++++++++++++++++++++++++++++++++++++ 1 file changed, 262 insertions(+) create mode 100644 Documentation/ia64/aliasing-test.c (limited to 'Documentation/ia64/aliasing-test.c') diff --git a/Documentation/ia64/aliasing-test.c b/Documentation/ia64/aliasing-test.c new file mode 100644 index 00000000..5caa2af3 --- /dev/null +++ b/Documentation/ia64/aliasing-test.c @@ -0,0 +1,262 @@ +/* + * Exercise /dev/mem mmap cases that have been troublesome in the past + * + * (c) Copyright 2007 Hewlett-Packard Development Company, L.P. + * Bjorn Helgaas + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +int sum; + +static int map_mem(char *path, off_t offset, size_t length, int touch) +{ + int fd, rc; + void *addr; + int *c; + + fd = open(path, O_RDWR); + if (fd == -1) { + perror(path); + return -1; + } + + if (fnmatch("/proc/bus/pci/*", path, 0) == 0) { + rc = ioctl(fd, PCIIOC_MMAP_IS_MEM); + if (rc == -1) + perror("PCIIOC_MMAP_IS_MEM ioctl"); + } + + addr = mmap(NULL, length, PROT_READ|PROT_WRITE, MAP_SHARED, fd, offset); + if (addr == MAP_FAILED) + return 1; + + if (touch) { + c = (int *) addr; + while (c < (int *) (addr + length)) + sum += *c++; + } + + rc = munmap(addr, length); + if (rc == -1) { + perror("munmap"); + return -1; + } + + close(fd); + return 0; +} + +static int scan_tree(char *path, char *file, off_t offset, size_t length, int touch) +{ + struct dirent **namelist; + char *name, *path2; + int i, n, r, rc = 0, result = 0; + struct stat buf; + + n = scandir(path, &namelist, 0, alphasort); + if (n < 0) { + perror("scandir"); + return -1; + } + + for (i = 0; i < n; i++) { + name = namelist[i]->d_name; + + if (fnmatch(".", name, 0) == 0) + goto skip; + if (fnmatch("..", name, 0) == 0) + goto skip; + + path2 = malloc(strlen(path) + strlen(name) + 3); + strcpy(path2, path); + strcat(path2, "/"); + strcat(path2, name); + + if (fnmatch(file, name, 0) == 0) { + rc = map_mem(path2, offset, length, touch); + if (rc == 0) + fprintf(stderr, "PASS: %s 0x%lx-0x%lx is %s\n", path2, offset, offset + length, touch ? "readable" : "mappable"); + else if (rc > 0) + fprintf(stderr, "PASS: %s 0x%lx-0x%lx not mappable\n", path2, offset, offset + length); + else { + fprintf(stderr, "FAIL: %s 0x%lx-0x%lx not accessible\n", path2, offset, offset + length); + return rc; + } + } else { + r = lstat(path2, &buf); + if (r == 0 && S_ISDIR(buf.st_mode)) { + rc = scan_tree(path2, file, offset, length, touch); + if (rc < 0) + return rc; + } + } + + result |= rc; + free(path2); + +skip: + free(namelist[i]); + } + free(namelist); + return result; +} + +char buf[1024]; + +static int read_rom(char *path) +{ + int fd, rc; + size_t size = 0; + + fd = open(path, O_RDWR); + if (fd == -1) { + perror(path); + return -1; + } + + rc = write(fd, "1", 2); + if (rc <= 0) { + perror("write"); + return -1; + } + + do { + rc = read(fd, buf, sizeof(buf)); + if (rc > 0) + size += rc; + } while (rc > 0); + + close(fd); + return size; +} + +static int scan_rom(char *path, char *file) +{ + struct dirent **namelist; + char *name, *path2; + int i, n, r, rc = 0, result = 0; + struct stat buf; + + n = scandir(path, &namelist, 0, alphasort); + if (n < 0) { + perror("scandir"); + return -1; + } + + for (i = 0; i < n; i++) { + name = namelist[i]->d_name; + + if (fnmatch(".", name, 0) == 0) + goto skip; + if (fnmatch("..", name, 0) == 0) + goto skip; + + path2 = malloc(strlen(path) + strlen(name) + 3); + strcpy(path2, path); + strcat(path2, "/"); + strcat(path2, name); + + if (fnmatch(file, name, 0) == 0) { + rc = read_rom(path2); + + /* + * It's OK if the ROM is unreadable. Maybe there + * is no ROM, or some other error occurred. The + * important thing is that no MCA happened. + */ + if (rc > 0) + fprintf(stderr, "PASS: %s read %d bytes\n", path2, rc); + else { + fprintf(stderr, "PASS: %s not readable\n", path2); + return rc; + } + } else { + r = lstat(path2, &buf); + if (r == 0 && S_ISDIR(buf.st_mode)) { + rc = scan_rom(path2, file); + if (rc < 0) + return rc; + } + } + + result |= rc; + free(path2); + +skip: + free(namelist[i]); + } + free(namelist); + return result; +} + +int main(void) +{ + int rc; + + if (map_mem("/dev/mem", 0, 0xA0000, 1) == 0) + fprintf(stderr, "PASS: /dev/mem 0x0-0xa0000 is readable\n"); + else + fprintf(stderr, "FAIL: /dev/mem 0x0-0xa0000 not accessible\n"); + + /* + * It's not safe to blindly read the VGA frame buffer. If you know + * how to poke the card the right way, it should respond, but it's + * not safe in general. Many machines, e.g., Intel chipsets, cover + * up a non-responding card by just returning -1, but others will + * report the failure as a machine check. + */ + if (map_mem("/dev/mem", 0xA0000, 0x20000, 0) == 0) + fprintf(stderr, "PASS: /dev/mem 0xa0000-0xc0000 is mappable\n"); + else + fprintf(stderr, "FAIL: /dev/mem 0xa0000-0xc0000 not accessible\n"); + + if (map_mem("/dev/mem", 0xC0000, 0x40000, 1) == 0) + fprintf(stderr, "PASS: /dev/mem 0xc0000-0x100000 is readable\n"); + else + fprintf(stderr, "FAIL: /dev/mem 0xc0000-0x100000 not accessible\n"); + + /* + * Often you can map all the individual pieces above (0-0xA0000, + * 0xA0000-0xC0000, and 0xC0000-0x100000), but can't map the whole + * thing at once. This is because the individual pieces use different + * attributes, and there's no single attribute supported over the + * whole region. + */ + rc = map_mem("/dev/mem", 0, 1024*1024, 0); + if (rc == 0) + fprintf(stderr, "PASS: /dev/mem 0x0-0x100000 is mappable\n"); + else if (rc > 0) + fprintf(stderr, "PASS: /dev/mem 0x0-0x100000 not mappable\n"); + else + fprintf(stderr, "FAIL: /dev/mem 0x0-0x100000 not accessible\n"); + + scan_tree("/sys/class/pci_bus", "legacy_mem", 0, 0xA0000, 1); + scan_tree("/sys/class/pci_bus", "legacy_mem", 0xA0000, 0x20000, 0); + scan_tree("/sys/class/pci_bus", "legacy_mem", 0xC0000, 0x40000, 1); + scan_tree("/sys/class/pci_bus", "legacy_mem", 0, 1024*1024, 0); + + scan_rom("/sys/devices", "rom"); + + scan_tree("/proc/bus/pci", "??.?", 0, 0xA0000, 1); + scan_tree("/proc/bus/pci", "??.?", 0xA0000, 0x20000, 0); + scan_tree("/proc/bus/pci", "??.?", 0xC0000, 0x40000, 1); + scan_tree("/proc/bus/pci", "??.?", 0, 1024*1024, 0); + + return rc; +} -- cgit v1.2.3