Revision ef36fa14 exec.c
| b/exec.c | ||
|---|---|---|
| 904 | 904 |
return fs.f_bsize; |
| 905 | 905 |
} |
| 906 | 906 |
|
| 907 |
static sigjmp_buf sigjump; |
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| 908 |
|
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| 909 |
static void sigbus_handler(int signal) |
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| 910 |
{
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| 911 |
siglongjmp(sigjump, 1); |
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| 912 |
} |
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| 913 |
|
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| 907 | 914 |
static void *file_ram_alloc(RAMBlock *block, |
| 908 | 915 |
ram_addr_t memory, |
| 909 | 916 |
const char *path) |
| ... | ... | |
| 913 | 920 |
char *c; |
| 914 | 921 |
void *area; |
| 915 | 922 |
int fd; |
| 916 |
#ifdef MAP_POPULATE |
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| 917 |
int flags; |
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| 918 |
#endif |
|
| 919 | 923 |
unsigned long hpagesize; |
| 920 | 924 |
|
| 921 | 925 |
hpagesize = gethugepagesize(path); |
| ... | ... | |
| 963 | 967 |
if (ftruncate(fd, memory)) |
| 964 | 968 |
perror("ftruncate");
|
| 965 | 969 |
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| 966 |
#ifdef MAP_POPULATE |
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| 967 |
/* NB: MAP_POPULATE won't exhaustively alloc all phys pages in the case |
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* MAP_PRIVATE is requested. For mem_prealloc we mmap as MAP_SHARED |
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| 969 |
* to sidestep this quirk. |
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| 970 |
*/ |
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| 971 |
flags = mem_prealloc ? MAP_POPULATE | MAP_SHARED : MAP_PRIVATE; |
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| 972 |
area = mmap(0, memory, PROT_READ | PROT_WRITE, flags, fd, 0); |
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#else |
|
| 974 | 970 |
area = mmap(0, memory, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0); |
| 975 |
#endif |
|
| 976 | 971 |
if (area == MAP_FAILED) {
|
| 977 | 972 |
perror("file_ram_alloc: can't mmap RAM pages");
|
| 978 | 973 |
close(fd); |
| 979 | 974 |
return (NULL); |
| 980 | 975 |
} |
| 976 |
|
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| 977 |
if (mem_prealloc) {
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| 978 |
int ret, i; |
|
| 979 |
struct sigaction act, oldact; |
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| 980 |
sigset_t set, oldset; |
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| 981 |
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| 982 |
memset(&act, 0, sizeof(act)); |
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| 983 |
act.sa_handler = &sigbus_handler; |
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| 984 |
act.sa_flags = 0; |
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| 985 |
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| 986 |
ret = sigaction(SIGBUS, &act, &oldact); |
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| 987 |
if (ret) {
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| 988 |
perror("file_ram_alloc: failed to install signal handler");
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| 989 |
exit(1); |
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| 990 |
} |
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| 991 |
|
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/* unblock SIGBUS */ |
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sigemptyset(&set); |
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sigaddset(&set, SIGBUS); |
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pthread_sigmask(SIG_UNBLOCK, &set, &oldset); |
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| 996 |
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| 997 |
if (sigsetjmp(sigjump, 1)) {
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| 998 |
fprintf(stderr, "file_ram_alloc: failed to preallocate pages\n"); |
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| 999 |
exit(1); |
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| 1000 |
} |
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| 1001 |
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| 1002 |
/* MAP_POPULATE silently ignores failures */ |
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| 1003 |
for (i = 0; i < (memory/hpagesize)-1; i++) {
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| 1004 |
memset(area + (hpagesize*i), 0, 1); |
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} |
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| 1006 |
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| 1007 |
ret = sigaction(SIGBUS, &oldact, NULL); |
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| 1008 |
if (ret) {
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perror("file_ram_alloc: failed to reinstall signal handler");
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exit(1); |
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} |
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| 1012 |
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pthread_sigmask(SIG_SETMASK, &oldset, NULL); |
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| 1014 |
} |
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| 1015 |
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| 981 | 1016 |
block->fd = fd; |
| 982 | 1017 |
return area; |
| 983 | 1018 |
} |
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