X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fdevice.c;h=5c18d996eaf76f53630a6c6f8ba9d19be62114a0;hp=8074a3eddc91402bc5926d1f5a5fb39acba819f4;hb=06d4c99ab3d479c1a7c087a87e82fe01626128f6;hpb=c4e2ceae941d02de5574becbfd3b4db15de2eda3

diff --git a/src/device.c b/src/device.c
index 8074a3edd..5c18d996e 100644
--- a/src/device.c
+++ b/src/device.c
@@ -188,12 +188,8 @@ static int device_update_unit(Manager *m, struct udev_device *dev, const char *p
         if ((r = device_find_escape_name(m, path, &u)) < 0)
                 return r;
 
-        /* If this is a different unit, then let's not merge things */
-        if (u && DEVICE(u)->sysfs && !path_equal(DEVICE(u)->sysfs, sysfs)) {
-                log_error("Hmm, something's broken. Asked to create two devices with same name but different sysfs paths. (%s vs %s)",
-                          DEVICE(u)->sysfs, sysfs);
+        if (u && DEVICE(u)->sysfs && !path_equal(DEVICE(u)->sysfs, sysfs))
                 return -EEXIST;
-        }
 
         if (!u) {
                 delete = true;
@@ -308,6 +304,7 @@ static int device_process_new_device(Manager *m, struct udev_device *dev, bool u
         first = udev_device_get_devlinks_list_entry(dev);
         udev_list_entry_foreach(item, first) {
                 const char *p;
+                struct stat st;
 
                 /* Don't bother with the /dev/block links */
                 p = udev_list_entry_get_name(item);
@@ -316,6 +313,18 @@ static int device_process_new_device(Manager *m, struct udev_device *dev, bool u
                     path_startswith(p, "/dev/char/"))
                         continue;
 
+                /* Verify that the symlink in the FS actually belongs
+                 * to this device. This is useful to deal with
+                 * conflicting devices, e.g. when two disks want the
+                 * same /dev/disk/by-label/xxx link because they have
+                 * the same label. We want to make sure that the same
+                 * device that won the symlink wins in systemd, so we
+                 * check the device node major/minor*/
+                if (stat(p, &st) >= 0)
+                        if ((!S_ISBLK(st.st_mode) && !S_ISCHR(st.st_mode)) ||
+                            st.st_rdev != udev_device_get_devnum(dev))
+                                continue;
+
                 device_update_unit(m, dev, p, false);
         }
 
@@ -392,6 +401,39 @@ static Unit *device_following(Unit *u) {
         return UNIT(first);
 }
 
+static int device_following_set(Unit *u, Set **_s) {
+        Device *d = DEVICE(u);
+        Device *other;
+        Set *s;
+        int r;
+
+        assert(d);
+        assert(_s);
+
+        if (!d->same_sysfs_prev && !d->same_sysfs_next) {
+                *_s = NULL;
+                return 0;
+        }
+
+        if (!(s = set_new(NULL, NULL)))
+                return -ENOMEM;
+
+        for (other = d->same_sysfs_next; other; other = other->same_sysfs_next)
+                if ((r = set_put(s, other)) < 0)
+                        goto fail;
+
+        for (other = d->same_sysfs_prev; other; other = other->same_sysfs_prev)
+                if ((r = set_put(s, other)) < 0)
+                        goto fail;
+
+        *_s = s;
+        return 1;
+
+fail:
+        set_free(s);
+        return r;
+}
+
 static void device_shutdown(Manager *m) {
         assert(m);
 
@@ -520,11 +562,9 @@ DEFINE_STRING_TABLE_LOOKUP(device_state, DeviceState);
 const UnitVTable device_vtable = {
         .suffix = ".device",
 
-        .no_requires = true,
         .no_instances = true,
         .no_snapshots = true,
         .no_isolate = true,
-        .no_alias = true,
 
         .init = device_init,
 
@@ -542,6 +582,7 @@ const UnitVTable device_vtable = {
         .bus_invalidating_properties =  bus_device_invalidating_properties,
 
         .following = device_following,
+        .following_set = device_following_set,
 
         .enumerate = device_enumerate,
         .shutdown = device_shutdown