/*
   * Exercise /dev/mem mmap cases that have been troublesome in the past
   *
   * (c) Copyright 2007 Hewlett-Packard Development Company, L.P.
   *	Bjorn Helgaas <bjorn.helgaas@hp.com>
   *
   * 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 <stdlib.h>
  #include <stdio.h>
  #include <sys/types.h>
  #include <dirent.h>
  #include <fcntl.h>
  #include <fnmatch.h>
  #include <string.h>

  #include <sys/ioctl.h>

  #include <sys/mman.h>
  #include <sys/stat.h>
  #include <unistd.h>

  #include <linux/pci.h>

  
  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
  ", path2, offset, offset + length, touch ? "readable" : "mappable");
  			else if (rc > 0)
  				fprintf(stderr, "PASS: %s 0x%lx-0x%lx not mappable
  ", path2, offset, offset + length);
  			else {
  				fprintf(stderr, "FAIL: %s 0x%lx-0x%lx not accessible
  ", 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
  ", path2, rc);

  			else {
  				fprintf(stderr, "PASS: %s not readable
  ", 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
  ");
  	else
  		fprintf(stderr, "FAIL: /dev/mem 0x0-0xa0000 not accessible
  ");
  
  	/*
  	 * 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
  ");
  	else
  		fprintf(stderr, "FAIL: /dev/mem 0xa0000-0xc0000 not accessible
  ");
  
  	if (map_mem("/dev/mem", 0xC0000, 0x40000, 1) == 0)
  		fprintf(stderr, "PASS: /dev/mem 0xc0000-0x100000 is readable
  ");
  	else
  		fprintf(stderr, "FAIL: /dev/mem 0xc0000-0x100000 not accessible
  ");
  
  	/*
  	 * 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
  ");
  	else if (rc > 0)
  		fprintf(stderr, "PASS: /dev/mem 0x0-0x100000 not mappable
  ");
  	else
  		fprintf(stderr, "FAIL: /dev/mem 0x0-0x100000 not accessible
  ");

  	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;

  }