On Mon, Oct 18, 2021 at 03:50:15PM +0100, David Howells wrote: > > Here's a set of patches that rewrites and simplifies the fscache index API > to remove the complex operation scheduling and object state machine in > favour of something much smaller and simpler. It is built on top of the > set of patches that removes the old API[1]. > > The operation scheduling API was intended to handle sequencing of cache > operations, which were all required (where possible) to run asynchronously > in parallel with the operations being done by the network filesystem, while > allowing the cache to be brought online and offline and interrupt service > with invalidation. > > However, with the advent of the tmpfile capacity in the VFS, an opportunity > arises to do invalidation much more easily, without having to wait for I/O > that's actually in progress: Cachefiles can simply cut over its file > pointer for the backing object attached to a cookie and abandon the > in-progress I/O, dismissing it upon completion. > > Future work there would involve using Omar Sandoval's vfs_link() with > AT_LINK_REPLACE[2] to allow an extant file to be displaced by a new hard > link from a tmpfile as currently I have to unlink the old file first. I had forgotten about that. It'd be great to finish that someday, but given the dead-end of the last discussion [1], we might need to hash it out the next time we can convene in person. 1:https://lore.kernel.org/linux-fsdevel/364531.1579265357@xxxxxxxxxxxxxxxxxxxxxx/
