On Friday May 5, gnb@xxxxxxx wrote: > > This patch seeks to remedy the interaction between knfsd and HSMs by > providing mechanisms to allow knfsd to tell an underlying filesystem > (which supports HSMs) not to block for reads, writes and truncates > of offline files. It's a port of a Linux 2.4 patch used in SGI's > ProPack distro since 2004 and in SLES9 since SP2. The patch: > > * provides a new ATTR_NO_BLOCK flag which the kernel can > use to tell a filesystem's inode_ops->setattr() operation not > to block when truncating an offline file. XFS already obeys > this flag (inside a #ifdef) > > * changes knfsd to provide ATTR_NO_BLOCK when it does the VFS > calls to implement the SETATTR NFS call. > > * changes knfsd to supply the O_NONBLOCK flag in the temporary > struct file it uses for VFS reads and writes, in order to ask > the filesystem not to block when reading or writing an offline > file. XFS already obeys this new semantic for O_NONBLOCK > (and in SLES9 so does JFS). > > * adds code to translate the -EAGAIN the filesystem returns when > it would have blocked, to the -ETIMEDOUT that knfsd expects. > Yes, I'm happy with this. All the changes make sense and look right. Thanks for persisting with it. I'll send it on up the chain... NeilBrown - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
