On Thu, Aug 11, 2016 at 08:48:04PM +0000, Andriy Gapon wrote: > Author: avg > Date: Thu Aug 11 20:48:03 2016 > New Revision: 303970 > URL: https://svnweb.freebsd.org/changeset/base/303970 > > Log: > MFC r303763,303791,303869: zfs: honour and make use of vfs vnode locking > protocol > > ZFS POSIX Layer is originally written for Solaris VFS which is very > different from FreeBSD VFS. Most importantly many things that FreeBSD VFS > manages on behalf of all filesystems are implemented in ZPL in a different > way. > Thus, ZPL contains code that is redundant on FreeBSD or duplicates VFS > functionality or, in the worst cases, badly interacts / interferes > with VFS. > > The most prominent problem is a deadlock caused by the lock order reversal > of vnode locks that may happen with concurrent zfs_rename() and lookup(). > The deadlock is a result of zfs_rename() not observing the vnode locking > contract expected by VFS. > > This commit removes all ZPL internal locking that protects parent-child > relationships of filesystem nodes. These relationships are protected > by vnode locks and the code is changed to take advantage of that fact > and to properly interact with VFS. > > Removal of the internal locking allowed all ZPL dmu_tx_assign calls to > use TXG_WAIT mode. > > Another victim, disputable perhaps, is ZFS support for filesystems with > mixed case sensitivity. That support is not provided by the OS anyway, > so in ZFS it was a buch of dead code. > > To do: > - replace ZFS_ENTER mechanism with VFS managed / visible mechanism > - replace zfs_zget with zfs_vget[f] as much as possible > - get rid of not really useful now zfs_freebsd_* adapters > - more cleanups of unneeded / unused code > - fix / replace .zfs support
MFC to 10.x/9.x planed? _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"