On Thu, Jul 11, 2013 at 3:53 PM, majianpeng <majianpeng@xxxxxxxxx> wrote: >>On Thu, Jul 11, 2013 at 9:17 AM, majianpeng <majianpeng@xxxxxxxxx> wrote: >>> Although, mmap-write of ceph update the time of file using >>> file_update_time.Because it don't mark the relative cap so the time >>> can't save. >> >>I think cephfs' mmap IO support is still broken. mmap IO does not respect >>ceph capabilities at all. It's possible that the kclient has no Fw cap when >>ceph_page_mkwrite is called. >> >>Yan, Zheng >> >> > Hi Yan, > For the read of mmap, i think we also add cap-check. > And i think we can rewrite the filemap_fault ect ceph_filemap_fault. > In ceph_filemap_fault, most code from filemap_fault, we only add cap-check for read-operation. > How about this or can you suggest anthor method? > This doesn't work. if a file is opened by multiple clients, the MDS doesn't issue Fcb caps to the client. If we add cap check to filemap_fault and page_mkwrite, they can block forever. To make mmap IO work properly, I think the only solution is introducing a new cache coherence protocol for mmap IO > Thanks! > Jianpeng Ma -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
