losetup: clean up code around LO_FLAGS_AUTOCLEAR

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/mount/lomount.c b/mount/lomount.c
index 793705249f0f707456e84f09ba97c30922ea4d6c..de28a26533e5d4c1116731b464e9af6ff0818394 100644 (file)
--- a/mount/lomount.c
+++ b/mount/lomount.c
@@ -102,24 +102,31 @@ is_loop_used(int fd)
        return ioctl (fd, LOOP_GET_STATUS, &li) == 0;
 }
 
-int
-is_loop_autoclear(const char *device)
+static int
+is_loopfd_autoclear(int fd)
 {
        struct loop_info lo;
        struct loop_info64 lo64;
-       int fd, rc = 0;
-
-       if ((fd = open(device, O_RDONLY)) < 0)
-               return 0;
 
        if (ioctl(fd, LOOP_GET_STATUS64, &lo64) == 0) {
                if (lo64.lo_flags & LO_FLAGS_AUTOCLEAR)
-                       rc = 1;
+                       return 1;
 
        } else if (ioctl(fd, LOOP_GET_STATUS, &lo) == 0) {
                if (lo.lo_flags & LO_FLAGS_AUTOCLEAR)
-                       rc = 1;
+                       return 1;
        }
+       return 0;
+}
+
+int
+is_loop_autoclear(const char *device)
+{
+       int fd, rc;
+
+       if ((fd = open(device, O_RDONLY)) < 0)
+               return 0;
+       rc = is_loopfd_autoclear(fd);
 
        close(fd);
        return rc;
@@ -748,23 +755,15 @@ set_loop(const char *device, const char *file, unsigned long long offset,
                        i = ioctl(fd, LOOP_SET_STATUS, &loopinfo);
                        if (i)
                                perror("ioctl: LOOP_SET_STATUS");
-                       else if (*options & SETLOOP_AUTOCLEAR)
-                       {
-                               i = ioctl(fd, LOOP_GET_STATUS, &loopinfo);
-                               if (i || !(loopinfo.lo_flags & LO_FLAGS_AUTOCLEAR))
-                                       *options &= ~SETLOOP_AUTOCLEAR;
-                       }
                }
                memset(&loopinfo, 0, sizeof(loopinfo));
        }
-       else if (*options & SETLOOP_AUTOCLEAR)
-       {
-               i = ioctl(fd, LOOP_GET_STATUS64, &loopinfo64);
-               if (i || !(loopinfo64.lo_flags & LO_FLAGS_AUTOCLEAR))
-                       *options &= ~SETLOOP_AUTOCLEAR;
-       }
-       memset(&loopinfo64, 0, sizeof(loopinfo64));
 
+       if ((*options & SETLOOP_AUTOCLEAR) && !is_loopfd_autoclear(fd))
+               /* kernel doesn't support loop auto-destruction */
+               *options &= ~SETLOOP_AUTOCLEAR;
+
+       memset(&loopinfo64, 0, sizeof(loopinfo64));
 
        if (i) {
                ioctl (fd, LOOP_CLR_FD, 0);