[PATCH 0/6] Extended file stat system call
smfrench at gmail.com
Thu Apr 19 11:14:06 MDT 2012
On Thu, Apr 19, 2012 at 9:05 AM, David Howells <dhowells at redhat.com> wrote:
> Implement a pair of new system calls to provide extended and further extensible
> Should the default for a network fs be to do an unconditional (heavyweight)
> stat with a flag to suppress going to the server to update the locally held
> attributes and flushing pending writebacks?
Even though we can use leases (oplocks) to avoid the roundrtrip, it is
probably too expensive to default to forcing a cache flush, especially
when a common case is to get the file creation time or inode number
information (stable vs volatile).
Would it be better to make the stable vs volatile inode number an attribute
of the volume or something returned by the proposed xstat?
> Should things like the Windows Archive, Hidden and System bits be handled
> through IOC flags, perhaps expanded to 64-bits?
Today I export these through an psuedo-xattr in cifs.ko, I am curious how
NTFS and FAT export these on linux.
> TO BE DONE
> Autofs, ntfs, btrfs, ...
Given the overlap in optional attributes between the network
protocol and local NTFS (and ReFS and to a lesser extent FAT)
I would expect cifs.ko and the ntfs implementations
info to map pretty closely.
> I should perhaps use u8/u32/u64 rather than uint8/32/64_t.
> Handle remote filesystems being offline and indicate this with
You already have support for an indicator for offline files (HSM),
would XSTAT_INFO_OFFLINE be intended for the case
where the network session to the server is disconnected
(and in which you case the application does not want to reconnect)?
More information about the samba-technical