Coverity: Try to avoid tainted values

CID#469253

src/fellow_cache.c

@@ -1635,18 +1635,21 @@ fellow_disk_seg_init(struct fellow_disk_seg *fds, uint8_t fht)
 	fds->fht = fht;
 }
 
-static void
-fellow_disk_seglist_init(struct fellow_disk_seglist *fdsl,
-    uint16_t ldsegs, uint8_t fht)
+static struct fellow_disk_seglist *
+fellow_disk_seglist_init(void *ptr, uint16_t ldsegs, uint8_t fht)
 {
+	struct fellow_disk_seglist *fdsl = ptr;
 	unsigned u;
 
+	AN(ptr);
+	assert(PAOK(ptr));
 	INIT_OBJ(fdsl, FELLOW_DISK_SEGLIST_MAGIC);
 	fdsl->version = 1;
 	fdsl->lsegs = ldsegs;
 	fdsl->fht = fht;
 	for (u = 0; u < ldsegs; u++)
 		fellow_disk_seg_init(&fdsl->segs[u], fht);
+	return (fdsl);
 }
 
 static inline void
@@ -1704,14 +1707,15 @@ fellow_cache_seglist_associate(
 	}
 }
 
-static void
-fellow_cache_seglist_init(struct fellow_cache_seglist *fcsl,
-    size_t space, struct fellow_cache_obj *fco)
+static struct fellow_cache_seglist *
+fellow_cache_seglist_init(void *ptr, size_t space, struct fellow_cache_obj *fco)
 {
-	uint16_t u;
+	struct fellow_cache_seglist *fcsl = ptr;
 	size_t lsegs;
+	uint16_t u;
 
-	AN(fcsl);
+	AN(ptr);
+	assert(PAOK(ptr));
 	assert(space > sizeof *fcsl);
 	INIT_OBJ(fcsl, FELLOW_CACHE_SEGLIST_MAGIC);
 	lsegs = space / sizeof *fcsl->segs;
@@ -1719,6 +1723,7 @@ fellow_cache_seglist_init(struct fellow_cache_seglist *fcsl,
 	fcsl->lsegs = (uint16_t)lsegs;
 	for (u = 0; u < fcsl->lsegs; u++)
 		fellow_cache_seg_init(&fcsl->segs[u], fco, FCS_INIT);
+	return (fcsl);
 }
 
 static void
@@ -1869,13 +1874,12 @@ fellow_cache_seglists_load(const struct fellow_cache *fc,
 
 		fcsl_mem = buddy_alloc1_ptr_extent_wait(fc->membuddy, FEP_META,
 		    sz, 0);
-		fcsl = fcsl_mem.ptr;
-		if (FC_INJ || fcsl == NULL) {
+		if (FC_INJ || fcsl_mem.ptr == NULL) {
 			err = FC_ERRSTR("disk seglist fcsl alloc failed");
 			goto err;
 		}
 
-		fellow_cache_seglist_init(fcsl,
+		fcsl = fellow_cache_seglist_init(fcsl_mem.ptr,
 		    fcsl_mem.size - sizeof *fcsl, fco);
 		fcsl->fdsl_sz = fdsl_mem.size;
 		fcsl->fcsl_sz = fcsl_mem.size;
@@ -1980,7 +1984,7 @@ fellow_cache_obj_new(struct fellow_cache *fc,
 
 	ssz = ((size_t)1 << fco_mem.bits) - sizeof *fco;
 
-	fellow_cache_seglist_init(&fco->seglist, ssz, fco);
+	(void) fellow_cache_seglist_init(&fco->seglist, ssz, fco);
 
 #define FDO_AUXATTR(U, l)						\
 	fellow_cache_seg_init(&fco->aa_##l##_seg, fco, FCS_INIT);
@@ -2111,10 +2115,9 @@ fellow_busy_obj_alloc(struct fellow_cache *fc,
 	fcs->refcnt = 2;
 	fellow_cache_seg_transition_locked_notincore(fcs, FCO_BUSY);
 
-	fdsl = (void *)((uint8_t *)fdo + sizeof *fdo + wsl);
-	assert(PAOK(fdsl));
-
-	fellow_disk_seglist_init(fdsl, ldsegs, fc->tune->hash_obj);
+	fdsl = fellow_disk_seglist_init(
+	    (void *)((uint8_t *)fdo + sizeof *fdo + wsl),
+	    ldsegs, fc->tune->hash_obj);
 	fellow_cache_seglist_associate(&fco->seglist, fdsl, FCS_USABLE);
 //	DBG("fdsl lsegs %u fcsl lsegs %u", fdsl->lsegs, fco->seglist.lsegs);
 
@@ -2306,14 +2309,12 @@ fellow_disk_seglist_alloc(struct fellow_busy *fbo,
 
 	buddy_alloc_wait_done(reqs);
 
-	fdsl = fdsl_mem.ptr;
-	AN(fdsl);
 	assert(fdsl_mem.size == fdr->size);
-	fellow_disk_seglist_init(fdsl, ldsegs, fht);
+	fdsl = fellow_disk_seglist_init(fdsl_mem.ptr, ldsegs, fht);
 
-	fcsl = fcsl_mem.ptr;
-	AN(fcsl);
-	fellow_cache_seglist_init(fcsl, fcsl_mem.size - sizeof *fcsl, fbo->fco);
+	AN(fcsl_mem.ptr);
+	fcsl = fellow_cache_seglist_init(fcsl_mem.ptr,
+	    fcsl_mem.size - sizeof *fcsl, fbo->fco);
 
 	fellow_cache_seglist_associate(fcsl, fdsl, FCS_USABLE);