[JFFS2] Fix unpoint length

Fix a couple of instances in JFFS2 where the unpoint() routine is
being called with the wrong length in cases where the point() routine
truncated a request.

Signed-off-by: Andy Lowe <alowe@mvista.com>
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

fs/jffs2/erase.c

@@ -340,7 +340,7 @@ static int jffs2_block_check_erase(struct jffs2_sb_info *c, struct jffs2_erasebl
 		if (retlen < c->sector_size) {
 			/* Don't muck about if it won't let us point to the whole erase sector */
 			D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", retlen));
-			c->mtd->unpoint(c->mtd, ebuf, jeb->offset, c->sector_size);
+			c->mtd->unpoint(c->mtd, ebuf, jeb->offset, retlen);
 			goto do_flash_read;
 		}
 		wordebuf = ebuf-sizeof(*wordebuf);

fs/jffs2/readinode.c

@@ -65,7 +65,7 @@ static int check_node_data(struct jffs2_sb_info *c, struct jffs2_tmp_dnode_info
 		err = c->mtd->point(c->mtd, ofs, len, &retlen, &buffer);
 		if (!err && retlen < tn->csize) {
 			JFFS2_WARNING("MTD point returned len too short: %zu instead of %u.\n", retlen, tn->csize);
-			c->mtd->unpoint(c->mtd, buffer, ofs, len);
+			c->mtd->unpoint(c->mtd, buffer, ofs, retlen);
 		} else if (err)
 			JFFS2_WARNING("MTD point failed: error code %d.\n", err);
 		else

fs/jffs2/scan.c

@@ -101,7 +101,7 @@ int jffs2_scan_medium(struct jffs2_sb_info *c)
 		if (!ret && pointlen < c->mtd->size) {
 			/* Don't muck about if it won't let us point to the whole flash */
 			D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", pointlen));
-			c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size);
+			c->mtd->unpoint(c->mtd, flashbuf, 0, pointlen);
 			flashbuf = NULL;
 		}
 		if (ret)