Revert "vl: Fix to create migration object before block backends again"

[mirror_qemu.git] / util / oslib-posix.c

diff --git a/util/oslib-posix.c b/util/oslib-posix.c
index 4ce1ba9ca427495af1c8232a8454ee1e92cd1cdc..88dda9cd39704be3e234542f13929eed4729b723 100644 (file)
--- a/util/oslib-posix.c
+++ b/util/oslib-posix.c
@@ -226,7 +226,7 @@ void qemu_vfree(void *ptr)
 void qemu_anon_ram_free(void *ptr, size_t size)
 {
     trace_qemu_anon_ram_free(ptr, size);
-    qemu_ram_munmap(ptr, size);
+    qemu_ram_munmap(-1, ptr, size);
 }
 
 void qemu_set_block(int fd)
@@ -244,7 +244,19 @@ void qemu_set_nonblock(int fd)
     f = fcntl(fd, F_GETFL);
     assert(f != -1);
     f = fcntl(fd, F_SETFL, f | O_NONBLOCK);
+#ifdef __OpenBSD__
+    if (f == -1) {
+        /*
+         * Previous to OpenBSD 6.3, fcntl(F_SETFL) is not permitted on
+         * memory devices and sets errno to ENODEV.
+         * It's OK if we fail to set O_NONBLOCK on devices like /dev/null,
+         * because they will never block anyway.
+         */
+        assert(errno == ENODEV);
+    }
+#else
     assert(f != -1);
+#endif
 }
 
 int socket_set_fast_reuse(int fd)
@@ -500,6 +512,59 @@ void os_mem_prealloc(int fd, char *area, size_t memory, int smp_cpus,
     }
 }
 
+uint64_t qemu_get_pmem_size(const char *filename, Error **errp)
+{
+    struct stat st;
+
+    if (stat(filename, &st) < 0) {
+        error_setg(errp, "unable to stat pmem file \"%s\"", filename);
+        return 0;
+    }
+
+#if defined(__linux__)
+    /* Special handling for devdax character devices */
+    if (S_ISCHR(st.st_mode)) {
+        char *subsystem_path = NULL;
+        char *subsystem = NULL;
+        char *size_path = NULL;
+        char *size_str = NULL;
+        uint64_t ret = 0;
+
+        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) {
+            error_setg(errp, "unable to read subsystem for pmem file \"%s\"",
+                       filename);
+            goto devdax_err;
+        }
+
+        if (!g_str_has_suffix(subsystem, "/dax")) {
+            error_setg(errp, "pmem file \"%s\" is not a dax device", filename);
+            goto devdax_err;
+        }
+
+        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)) {
+            error_setg(errp, "unable to read size for pmem file \"%s\"",
+                       size_path);
+            goto devdax_err;
+        }
+
+        ret = g_ascii_strtoull(size_str, NULL, 0);
+
+devdax_err:
+        g_free(size_str);
+        g_free(size_path);
+        g_free(subsystem);
+        g_free(subsystem_path);
+        return ret;
+    }
+#endif /* defined(__linux__) */
+
+    return st.st_size;
+}
 
 char *qemu_get_pid_name(pid_t pid)
 {