kernel.git/fs/ceph/caps.c, branch linux-2.6.37.y

ceph: fix rdcache_gen usage and invalidate

2010-11-08T15:29:05Z

We used to use rdcache_gen to indicate whether we "might" have cached pages. Now we just look at the mapping to determine that. However, some old behavior remains from that transition. First, rdcache_gen == 0 no longer means we have no pages. That can happen at any time (presumably when we carry FILE_CACHE). We should not reset it to zero, and we should not check that it is zero. That means that the only purpose for rdcache_revoking is to resolve races between new issues of FILE_CACHE and an async invalidate. If they are equal, we should invalidate. On success, we decrement rdcache_revoking, so that it is no longer equal to rdcache_gen. Similarly, if we success in doing a sync invalidate, set revoking = gen - 1. (This is a small optimization to avoid doing unnecessary invalidate work and does not affect correctness.) Signed-off-by: Sage Weil

ceph: re-request max_size if cap auth changes

2010-11-07T17:39:23Z

If the auth cap migrates to another MDS, clear requested_max_size so that we resend any pending max_size increase requests. This fixes potential hangs on writes that extend a file and race with an cap migration between MDSs. Signed-off-by: Sage Weil

Revert "ceph: update issue_seq on cap grant"

2010-10-28T04:05:54Z

This reverts commit d91f2438d881514e4a923fd786dbd94b764a9440. The intent of issue_seq is to distinguish between mds->client messages that (re)create the cap and those that do not, which means we should _only_ be updating that value in the create paths. By updating it in handle_cap_grant, we reset it to zero, which then breaks release. The larger question is what workload/problem made me think it should be updated here... Signed-off-by: Sage Weil

ceph: use mapping->nrpages to determine if mapping is empty

2010-10-20T22:38:15Z

This is simpler and faster. Signed-off-by: Sage Weil

ceph: only invalidate on check_caps if we actually have pages

2010-10-20T22:38:15Z

The i_rdcache_gen value only implies we MAY have cached pages; actually check the mapping to see if it's worth bothering with an invalidate. Signed-off-by: Sage Weil

ceph: factor out libceph from Ceph file system

2010-10-20T22:37:28Z

This factors out protocol and low-level storage parts of ceph into a separate libceph module living in net/ceph and include/linux/ceph. This is mostly a matter of moving files around. However, a few key pieces of the interface change as well: - ceph_client becomes ceph_fs_client and ceph_client, where the latter captures the mon and osd clients, and the fs_client gets the mds client and file system specific pieces. - Mount option parsing and debugfs setup is correspondingly broken into two pieces. - The mon client gets a generic handler callback for otherwise unknown messages (mds map, in this case). - The basic supported/required feature bits can be expanded (and are by ceph_fs_client). No functional change, aside from some subtle error handling cases that got cleaned up in the refactoring process. Signed-off-by: Sage Weil

ceph: update issue_seq on cap grant

2010-10-07T15:01:50Z

We need to update the issue_seq on any grant operation, be it via an MDS reply or a separate grant message. The update in the grant path was missing. This broke cap release for inodes in which the MDS sent an explicit grant message that was not soon after followed by a successful MDS reply on the same inode. Also fix the signedness on seq locals. Signed-off-by: Sage Weil

ceph: send cap release message early on failed revoke.

2010-10-07T15:00:24Z

If an MDS tries to revoke caps that we don't have, we want to send releases early since they probably contain the caps message the MDS is looking for. Previously, we only sent the messages if we didn't have the inode either. But in a multi-mds system we can retain the inode after dropping all caps for a single MDS. Signed-off-by: Greg Farnum Signed-off-by: Sage Weil

ceph: check mapping to determine if FILE_CACHE cap is used

2010-09-17T16:54:31Z

See if the i_data mapping has any pages to determine if the FILE_CACHE capability is currently in use, instead of assuming it is any time the rdcache_gen value is set (i.e., issued -> used). This allows the MDS RECALL_STATE process work for inodes that have cached pages. Signed-off-by: Sage Weil

ceph: only send one flushsnap per cap_snap per mds session

2010-09-17T15:03:08Z

Sending multiple flushsnap messages is problematic because we ignore the response if the tid doesn't match, and the server may only respond to each one once. It's also a waste. So, skip cap_snaps that are already on the flushing list, unless the caller tells us to resend (because we are reconnecting). Signed-off-by: Sage Weil