UBIFS: refactor ubifs_rcvry_gc_commit

This commits refactors and cleans up 'ubifs_rcvry_gc_commit()' which was quite
untidy, also removes the commentary which was not 100% correct.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

diff --git a/fs/ubifs/recovery.c b/fs/ubifs/recovery.c
index 11776ae..d28db1e 100644 (file)
--- a/fs/ubifs/recovery.c
+++ b/fs/ubifs/recovery.c
@@ -1138,44 +1138,26 @@ int ubifs_rcvry_gc_commit(struct ubifs_info *c)
 {
        struct ubifs_wbuf *wbuf = &c->jheads[GCHD].wbuf;
        struct ubifs_lprops lp;
-       int lnum, err;
+       int err;
 
        c->gc_lnum = -1;
-       if (wbuf->lnum == -1) {
-               dbg_rcvry("no GC head LEB");
-               return grab_empty_leb(c);
-       }
-       /*
-        * See whether the used space in the dirtiest LEB fits in the GC head
-        * LEB.
-        */
-       if (wbuf->offs == c->leb_size) {
-               dbg_rcvry("no room in GC head LEB");
+       if (wbuf->lnum == -1 || wbuf->offs == c->leb_size) {
+               dbg_rcvry("no GC head: wbuf->lnum %d, wbuf->offs %d",
+                         wbuf->lnum, wbuf->offs);
                return grab_empty_leb(c);
        }
+
        err = ubifs_find_dirty_leb(c, &lp, wbuf->offs, 2);
        if (err) {
-               /*
-                * There are no dirty or empty LEBs subject to here being
-                * enough for the index. Try to use
-                * 'ubifs_find_free_leb_for_idx()', which will return any empty
-                * LEBs (ignoring index requirements). If the index then
-                * doesn't have enough LEBs the recovery commit will fail -
-                * which is the  same result anyway i.e. recovery fails. So
-                * there is no problem ignoring index  requirements and just
-                * grabbing a free LEB since we have already established there
-                * is not a dirty LEB we could have used instead.
-                */
-               if (err == -ENOSPC) {
-                       dbg_rcvry("could not find a dirty LEB");
-                       return grab_empty_leb(c);
-               }
-               return err;
+               if (err != -ENOSPC)
+                       return err;
+
+               dbg_rcvry("could not find a dirty LEB");
+               return grab_empty_leb(c);
        }
 
        ubifs_assert(!(lp.flags & LPROPS_INDEX));
        ubifs_assert(lp.free + lp.dirty >= wbuf->offs);
-       lnum = lp.lnum;
 
        /*
         * We run the commit before garbage collection otherwise subsequent
@@ -1185,11 +1167,8 @@ int ubifs_rcvry_gc_commit(struct ubifs_info *c)
        err = ubifs_run_commit(c);
        if (err)
                return err;
-       /*
-        * The data in the dirtiest LEB fits in the GC head LEB, so do the GC
-        * - use locking to keep 'ubifs_assert()' happy.
-        */
-       dbg_rcvry("GC'ing LEB %d", lnum);
+
+       dbg_rcvry("GC'ing LEB %d", lp.lnum);
        mutex_lock_nested(&wbuf->io_mutex, wbuf->jhead);
        err = ubifs_garbage_collect_leb(c, &lp);
        if (err >= 0) {
@@ -1205,14 +1184,16 @@ int ubifs_rcvry_gc_commit(struct ubifs_info *c)
                        err = -EINVAL;
                return err;
        }
-       if (err != LEB_RETAINED) {
-               dbg_err("GC returned %d", err);
+
+       ubifs_assert(err == LEB_RETAINED);
+       if (err != LEB_RETAINED)
                return -EINVAL;
-       }
+
        err = ubifs_leb_unmap(c, c->gc_lnum);
        if (err)
                return err;
-       dbg_rcvry("allocated LEB %d for GC", lnum);
+
+       dbg_rcvry("allocated LEB %d for GC", lp.lnum);
        return 0;
 }