On Wed, Apr 29, 2009 at 10:37:34AM -0500, Eric Sandeen wrote: > Theodore Tso wrote: > > On Wed, Apr 29, 2009 at 10:17:21AM +0530, Aneesh Kumar K.V wrote: > >> Block number '0' should not be used as the fake block number for > >> the delayed new buffer. This will result in vfs calling umap_underlying_metadata for > >> block number '0'. So use -1 instead. > > > > sector_t is an unsigned type, so we probably want to use ~0 instead of > > -1. I can fix this up before we apply into the patch queue. > > I don't think that helps. The point is to have a block number which is > invalid, therefore won't get unmapped or accidentally written to ... This is more of a type-safety thing to eliminate compiler warnings. We could use something like s_blocks_count instead, which has less chance of wrapping, but by the time we get to the bh level, the risk of wrapping should be minimal, and ~0 (or -1) is more distinctive when debugging/tracing. - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
