> IMO, it's no use to check the correctness for the inode when ->i_count ==
> 0. We can reuse the memory of the client side inode, that's true,
> but we don't need to check old data against new one at that time.
I don't understand what you mean by this. As I see it, close-to-open
consistency checking mandates that you do this. What if somebody changed the
data on the server while you had the file closed?
Furthermore, inode->i_count == 0 offers no guarantees that the client doesn't
for instance have dirty pages to write out.
Messing around with the value of i_mode in nfs_find_actor as you want to do
in your patch is going to introduce new dimensions to this problem. For
instance, magically changing a regular file into a symlink without first
flushing out dirty pages and clearing the page cache is certainly going to
produce som "interesting" results...
As I said yesterday: a test of the form
if ((inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT))
return 0;
in nfs_find_actor might make sense since that forces the creation of a new
inode. However it doesn't help at all with the same race if inode->i_mode
hasn't changed. There is simply no way you can test for whether or not the
file is the same on the server.
Cheers,
Trond
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