#include <fcntl.h>
#include <sys/types.h>
#include <sys/mman.h>
-#include <sys/statfs.h>
#include "kern_util.h"
#include "user.h"
#include "user_util.h"
#include <sys/param.h>
-static char *default_tmpdir = "/tmp";
static char *tempdir = NULL;
static void __init find_tempdir(void)
break;
}
if((dir == NULL) || (*dir == '\0'))
- dir = default_tmpdir;
+ dir = "/tmp";
tempdir = malloc(strlen(dir) + 2);
if(tempdir == NULL){
strcat(tempdir, "/");
}
-/* This will return 1, with the first character in buf being the
- * character following the next instance of c in the file. This will
- * read the file as needed. If there's an error, -errno is returned;
- * if the end of the file is reached, 0 is returned.
- */
-static int next(int fd, char *buf, int size, char c)
-{
- int n, len;
- char *ptr;
-
- while((ptr = strchr(buf, c)) == NULL){
- n = read(fd, buf, size - 1);
- if(n == 0)
- return 0;
- else if(n < 0)
- return -errno;
-
- buf[n] = '\0';
- }
-
- ptr++;
- len = strlen(ptr);
- memmove(buf, ptr, len + 1);
-
- /* Refill the buffer so that if there's a partial string that we care
- * about, it will be completed, and we can recognize it.
- */
- n = read(fd, &buf[len], size - len - 1);
- if(n < 0)
- return -errno;
-
- buf[len + n] = '\0';
- return 1;
-}
-
-static int checked_tmpdir = 0;
-
-/* Look for a tmpfs mounted at /dev/shm. I couldn't find a cleaner
- * way to do this than to parse /proc/mounts. statfs will return the
- * same filesystem magic number and fs id for both /dev and /dev/shm
- * when they are both tmpfs, so you can't tell if they are different
- * filesystems. Also, there seems to be no other way of finding the
- * mount point of a filesystem from within it.
- *
- * If a /dev/shm tmpfs entry is found, then we switch to using it.
- * Otherwise, we stay with the default /tmp.
- */
-static void which_tmpdir(void)
-{
- int fd, found;
- char buf[128] = { '\0' };
-
- if(checked_tmpdir)
- return;
-
- checked_tmpdir = 1;
-
- printf("Checking for tmpfs mount on /dev/shm...");
-
- fd = open("/proc/mounts", O_RDONLY);
- if(fd < 0){
- printf("failed to open /proc/mounts, errno = %d\n", errno);
- return;
- }
-
- while(1){
- found = next(fd, buf, sizeof(buf) / sizeof(buf[0]), ' ');
- if(found != 1)
- break;
-
- if(!strncmp(buf, "/dev/shm", strlen("/dev/shm")))
- goto found;
-
- found = next(fd, buf, sizeof(buf) / sizeof(buf[0]), '\n');
- if(found != 1)
- break;
- }
-
-err:
- if(found == 0)
- printf("nothing mounted on /dev/shm\n");
- else if(found < 0)
- printf("read returned errno %d\n", -found);
-
- return;
-
-found:
- found = next(fd, buf, sizeof(buf) / sizeof(buf[0]), ' ');
- if(found != 1)
- goto err;
-
- if(strncmp(buf, "tmpfs", strlen("tmpfs"))){
- printf("not tmpfs\n");
- return;
- }
-
- printf("OK\n");
- default_tmpdir = "/dev/shm";
-}
-
/*
* This proc still used in tt-mode
* (file: kernel/tt/ptproxy/proxy.c, proc: start_debugger).
*/
int make_tempfile(const char *template, char **out_tempname, int do_unlink)
{
- char *tempname;
+ char tempname[MAXPATHLEN];
int fd;
- which_tmpdir();
- tempname = malloc(MAXPATHLEN);
-
find_tempdir();
- if (template[0] != '/')
+ if (*template != '/')
strcpy(tempname, tempdir);
else
- tempname[0] = '\0';
+ *tempname = 0;
strcat(tempname, template);
fd = mkstemp(tempname);
if(fd < 0){
fprintf(stderr, "open - cannot create %s: %s\n", tempname,
strerror(errno));
- goto out;
+ return -1;
}
if(do_unlink && (unlink(tempname) < 0)){
perror("unlink");
- goto out;
+ return -1;
}
if(out_tempname){
- *out_tempname = tempname;
- } else {
- free(tempname);
+ *out_tempname = strdup(tempname);
+ if(*out_tempname == NULL){
+ perror("strdup");
+ return -1;
+ }
}
return(fd);
-out:
- free(tempname);
- return -1;
}
#define TEMPNAME_TEMPLATE "vm_file-XXXXXX"
exit(1);
}
- /* Seek to len - 1 because writing a character there will
- * increase the file size by one byte, to the desired length.
- */
- if (lseek64(fd, len - 1, SEEK_SET) < 0) {
- perror("os_seek_file");
+ if (lseek64(fd, len, SEEK_SET) < 0) {
+ perror("os_seek_file");
exit(1);
}
return(fd);
}
-int create_mem_file(unsigned long long len)
+static int create_anon_file(unsigned long long len)
{
- int err, fd;
+ void *addr;
+ int fd;
- fd = create_tmp_file(len);
+ fd = open("/dev/anon", O_RDWR);
+ if(fd < 0) {
+ perror("opening /dev/anon");
+ exit(1);
+ }
- err = os_set_exec_close(fd, 1);
- if(err < 0){
- errno = -err;
- perror("exec_close");
+ addr = mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
+ if(addr == MAP_FAILED){
+ perror("mapping physmem file");
+ exit(1);
}
+ munmap(addr, len);
+
return(fd);
}
+extern int have_devanon;
-void check_tmpexec(void)
+int create_mem_file(unsigned long long len)
{
- void *addr;
- int err, fd = create_tmp_file(UM_KERN_PAGE_SIZE);
+ int err, fd;
- addr = mmap(NULL, UM_KERN_PAGE_SIZE,
- PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE, fd, 0);
- printf("Checking PROT_EXEC mmap in %s...",tempdir);
- fflush(stdout);
- if(addr == MAP_FAILED){
- err = errno;
- perror("failed");
- if(err == EPERM)
- printf("%s must be not mounted noexec\n",tempdir);
- exit(1);
- }
- printf("OK\n");
- munmap(addr, UM_KERN_PAGE_SIZE);
+ if(have_devanon)
+ fd = create_anon_file(len);
+ else fd = create_tmp_file(len);
- close(fd);
+ err = os_set_exec_close(fd, 1);
+ if(err < 0){
+ errno = -err;
+ perror("exec_close");
+ }
+ return(fd);
}
git://git.onelab.eu / linux-2.6.git / blobdiff