Re: [PATCH RFC 06/24] vfs: break parent dir delegations in open(..., O_CREAT) codepath
From: Stefan Metzmacher <metze@samba.org>
Date: 2024-03-18 08:25:40
Also in:
linux-cifs, linux-fsdevel, linux-nfs, linux-unionfs, lkml, netfs
Hi Jeff,
quoted hunk ↗ jump to hunk
In order to add directory delegation support, we need to break delegations on the parent whenever there is going to be a change in the directory. Add a delegated_inode parameter to lookup_open and have it break the delegation. Then, open_last_lookups can wait for the delegation break and retry the call to lookup_open once it's done. Signed-off-by: Jeff Layton <jlayton@kernel.org> --- fs/namei.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-)diff --git a/fs/namei.c b/fs/namei.c index f00d8d708001..88598a62ec64 100644 --- a/fs/namei.c +++ b/fs/namei.c@@ -3404,7 +3404,7 @@ static struct dentry *atomic_open(struct nameidata *nd, struct dentry *dentry, */ static struct dentry *lookup_open(struct nameidata *nd, struct file *file, const struct open_flags *op, - bool got_write) + bool got_write, struct inode **delegated_inode)
Does NFS has a concept of lease keys and parent lease keys? In SMB it's possible that the client passes a lease key (16 client chosen bytes) to a directory open, when asking for a directory lease. Then operations on files within that directory, take that lease key from the directory as 'parent lease keys' in addition to a unique lease key for the file. That way a client can avoid breaking its own directory leases when creating/move/delete... files in the directory. metze