On Wed, Jul 17, 2013 at 04:50:00PM -0400, J. Bruce Fields wrote: > From: "J. Bruce Fields" <bfields@xxxxxxxxxx> > > Changes since version 8, thanks to dchinner and jlayton for review: > > - additional warnings in lock_two_nondirectories > - lock_two_nondirectories handles NULL second argument, > simplifying vfs_rename_other > - kerneldoc comments on notify_change, vfs_link, vfs_rename, > vfs_unlink, to explain delegated_inode argument. > - make clear non-support of write delegations in > generic_add_lease > - rebase to 3.11-rc1 (Not addressed: Dave's concerns about possible incompatibility with ordering of filesystem-specific locks, in xfs and possibly also in other filesystems.) --b. > > Introduction copied from previous posting: > > This patch series implements read delegations, which allow NFSv4 clients > to perform read opens without contacting the server, by promising to > call back to clients before modifying the data, metadata, or set of > links pointing to a file. > > The main recent change was in response to review from Linus, who didn't > want us to hang under directory i_mutex's on timeouts communicating with > unresponsive clients. > > So, this version of the series drops the i_mutex before waiting. The > logic ends up looking something like: > > acquire locks > look up inode > test for delegation; if found: > take reference on inode > release locks > wait for delegation break > drop reference on inode > retry > > The initial test for a delegation happens after the lock on the > delegated inode is acquired, but additional directory mutexes may have > been acquired further up the call stack. I therefore add a "struct > inode **" argument to any intervening functions, which we use to pass > the inode back up to the caller in the case it needs to wait for the > delegation to be broken. > > I also allow callers to pass in NULL for the "struct inode **" argument > to indicate they'd rather just fail than wait for a delegation. For > example, as long as ecryptfs isn't exportable I assume they'd rather not > see retry logic there that they won't use. But I may have misjudged in > some of these cases. > > J. Bruce Fields (16): > vfs: pull ext4's double-i_mutex-locking into common code > vfs: don't use PARENT/CHILD lock classes for non-directories > vfs: rename I_MUTEX_QUOTA now that it's not used for quotas > vfs: take i_mutex on renamed file > locks: introduce new FL_DELEG lock flag > locks: implement delegations > namei: minor vfs_unlink cleanup > locks: break delegations on unlink > locks: helper functions for delegation breaking > locks: break delegations on rename > locks: break delegations on link > locks: break delegations on any attribute modification > nfsd4: minor nfs4_setlease cleanup > nfsd4: delay setting current_fh in open > nfsd4: close open-deleg/unlink/rename race > nfsd4: break only delegations when appropriate > > Documentation/filesystems/directory-locking | 31 ++++-- > drivers/base/devtmpfs.c | 6 +- > fs/attr.c | 25 ++++- > fs/cachefiles/interface.c | 4 +- > fs/cachefiles/namei.c | 4 +- > fs/ecryptfs/inode.c | 6 +- > fs/ext4/ext4.h | 2 - > fs/ext4/ioctl.c | 4 +- > fs/ext4/move_extent.c | 40 +------- > fs/hpfs/namei.c | 2 +- > fs/inode.c | 42 ++++++++- > fs/locks.c | 57 ++++++++--- > fs/namei.c | 135 +++++++++++++++++++++++---- > fs/nfsd/nfs4proc.c | 36 +++---- > fs/nfsd/nfs4state.c | 66 ++++++++++--- > fs/nfsd/vfs.c | 41 ++------ > fs/nfsd/xdr4.h | 3 +- > fs/open.c | 22 ++++- > fs/utimes.c | 9 +- > include/linux/fs.h | 72 +++++++++++--- > ipc/mqueue.c | 2 +- > 21 files changed, 433 insertions(+), 176 deletions(-) > > -- > 1.7.9.5 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
