diff options
Diffstat (limited to 'exec.c')
| -rw-r--r-- | exec.c | 34 |
1 files changed, 33 insertions, 1 deletions
@@ -1791,7 +1791,39 @@ long qemu_maxrampagesize(void) #ifdef CONFIG_POSIX static int64_t get_file_size(int fd) { - int64_t size = lseek(fd, 0, SEEK_END); + int64_t size; +#if defined(__linux__) + struct stat st; + + if (fstat(fd, &st) < 0) { + return -errno; + } + + /* Special handling for devdax character devices */ + if (S_ISCHR(st.st_mode)) { + g_autofree char *subsystem_path = NULL; + g_autofree char *subsystem = NULL; + + subsystem_path = g_strdup_printf("/sys/dev/char/%d:%d/subsystem", + major(st.st_rdev), minor(st.st_rdev)); + subsystem = g_file_read_link(subsystem_path, NULL); + + if (subsystem && g_str_has_suffix(subsystem, "/dax")) { + g_autofree char *size_path = NULL; + g_autofree char *size_str = NULL; + + size_path = g_strdup_printf("/sys/dev/char/%d:%d/size", + major(st.st_rdev), minor(st.st_rdev)); + + if (g_file_get_contents(size_path, &size_str, NULL, NULL)) { + return g_ascii_strtoll(size_str, NULL, 0); + } + } + } +#endif /* defined(__linux__) */ + + /* st.st_size may be zero for special files yet lseek(2) works */ + size = lseek(fd, 0, SEEK_END); if (size < 0) { return -errno; } |