XXXX give me a better summary

@@ -649,11 +649,12 @@
         off = pp->p_offset;
 
         doff = off;
         dlen = PAGESIZE;
 
-        if (err = swap_newphysname(vp, off, &doff, &dlen, &pvp, &poff)) {
+        /* All newphysname() failure types are treated the same. */
+        if (swap_newphysname(vp, off, &doff, &dlen, &pvp, &poff) != 0) {
                 err = (flags == (B_ASYNC | B_FREE) ? ENOMEM : 0);
                 hat_setmod(pp);
                 page_io_unlock(pp);
                 page_unlock(pp);
                 goto out;

@@ -693,12 +694,11 @@
                         continue;
                 }
                 /* Get new physical backing store for the page */
                 doff = off;
                 dlen = PAGESIZE;
-                if (err = swap_newphysname(vp, off, &doff, &dlen,
-                    &pvp, &poff)) {
+                if (swap_newphysname(vp, off, &doff, &dlen, &pvp, &poff) != 0) {
                         swap_otherfail++;
                         swap_otherpages += btop(klsz);
                         hat_setmod(pp);
                         page_io_unlock(pp);
                         page_unlock(pp);