On Tue, Jun 20, 2017 at 09:42:55AM -0600, Ross Zwisler wrote: > On Mon, Jun 19, 2017 at 10:22:14PM -0700, Darrick J. Wong wrote: > <> > > Fourth, the VFS entry points for things like read, write, truncate, > > utimes, fallocate, etc. all just bail out if S_IOMAP_FROZEN is set on a > > file, so that the block map cannot be modified. mmap is still allowed, > > as we've discussed. /Maybe/ we can allow fallocate to extend a file > > with zeroed extents (it will be slow) as I've heard murmurs about > > wanting to be able to extend a file, maybe not. > > Read and write should still be allowed, right?
<shrug> I had thought the usage model was pretty slanted towards mmap, but it's not a big deal to turn read/writes into glorified memcpy, provided we reject the io request if it goes past EOF. --D > -- > To unsubscribe from this list: send the line "unsubscribe linux-api" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html
