[fs-btrfs] question about apparent useless function call

From: Gustavo A. R. Silva
Date: Wed May 17 2017 - 18:38:49 EST



Hello everybody,

While looking into Coverity ID 1398149 I ran into the following piece of code at fs/btrfs/zlib.c:295:

295done:
296 zlib_inflateEnd(&workspace->strm);
297 if (data_in)
298 kunmap(pages_in[page_in_index]);
299 if (!ret)
300 zero_fill_bio(orig_bio);
301 return ret;
302}

The issue here is that calling function zlib_inflateEnd() at line 296 _seems_ to be useless once this function _seems_ to be only useful for its return value, which is ignored. The same for line 388.

Can someone help me understand what is the purpose of these calls?
Should them be removed, or the return value actually evaluated?

I'd really appreciate any comment on this.

Thank you!
--
Gustavo A. R. Silva