• Yan, Zheng's avatar
    ceph: improve fscache revalidation · f7f7e7a0
    Yan, Zheng authored
    There are several issues in fscache revalidation code.
    - In ceph_revalidate_work(), fscache_invalidate() is called when
      fscache_check_consistency() return 0. This is complete wrong
      because 0 means cache is valid.
    - Handle_cap_grant() calls ceph_queue_revalidate() if client
      already has CAP_FILE_CACHE. This code is confusing. Client
      should revalidate the cache each time it got CAP_FILE_CACHE
    - In Handle_cap_grant(), fscache_invalidate() is called if MDS
      revokes CAP_FILE_CACHE. This is inconsistency with the case
      that inode get evicted. In the later case, the cache is not
      discarded. Client may use the cache when inode is reloaded.
    This patch moves the fscache revalidation into ceph_get_caps().
    Client revalidates the cache after it gets CAP_FILE_CACHE.
    i_rdcache_gen should keep constance while CAP_FILE_CACHE is
    used. If i_fscache_gen is not equal to i_rdcache_gen, client
    needs to check cache's consistency.
    Signed-off-by: default avatarYan, Zheng <zyan@redhat.com>
cache.h 4.71 KB