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 <sage@newdream.net>
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 <sage@newdream.net>
This reverts commit d91f2438d8.
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 <sage@newdream.net>
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 <sage@newdream.net>
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 <sage@newdream.net>
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 <sage@newdream.net>
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 <gregf@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
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 <sage@newdream.net>
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 <sage@newdream.net>
Stop sending FLUSHSNAP messages when we hit a capsnap that has dirty_pages
or is still writing. We'll send the newer capsnaps only after the older
ones complete.
Signed-off-by: Sage Weil <sage@newdream.net>
We used to use i_head_snapc to keep track of which snapc the current epoch
of dirty data was dirtied under. It is used by queue_cap_snap to set up
the cap_snap. However, since we queue cap snaps for any dirty caps, not
just for dirty file data, we need to keep a valid i_head_snapc anytime
we have dirty|flushing caps. This fixes a NULL pointer deref in
queue_cap_snap when writing back dirty caps without data (e.g.,
snaptest-authwb.sh).
Signed-off-by: Sage Weil <sage@newdream.net>
When we snapshot dirty metadata that needs to be written back to the MDS,
include dirty xattr metadata. Make the capsnap reference the encoded
xattr blob so that it will be written back in the FLUSHSNAP op.
Also fix the capsnap creation guard to include dirty auth or file bits,
not just tests specific to dirty file data or file writes in progress
(this fixes auth metadata writeback).
Signed-off-by: Sage Weil <sage@newdream.net>
We should include the xattr metadata blob in the cap update message any
time we are flushing dirty state, NOT just when we are also dropping the
cap. This fixes async xattr writeback.
Also, clean up the code slightly to avoid duplicating the bit test.
Signed-off-by: Sage Weil <sage@newdream.net>
Normally, if the Fb cap bit is being revoked, we queue an async writeback.
If there is no dirty data but we still hold the cap, this leaves the
client sitting around doing nothing until the cap timeouts expire and the
cap is released on its own (as it would have been without the revocation).
Instead, only queue writeback if the bit is actually used (i.e., we have
dirty data). If not, we can reply to the revocation immediately.
Signed-off-by: Sage Weil <sage@newdream.net>
When we get a cap EXPORT message, make sure we are connected to all export
targets to ensure we can handle the matching IMPORT.
Signed-off-by: Sage Weil <sage@newdream.net>
Caps related accounting is now being done per mds client instead
of just being global. This prepares ground work for a later revision
of the caps preallocated reservation list.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
If we have a capsnap but no auth cap (e.g. because it is migrating to
another mds), bail out and do nothing for now. Do NOT remove the capsnap
from the flush list.
Signed-off-by: Sage Weil <sage@newdream.net>
The caps revocation should either initiate writeback, invalidateion, or
call check_caps to ack or do the dirty work. The primary question is
whether we can get away with only checking the auth cap or whether all
caps need to be checked.
The old code was doing...something else. At the very least, revocations
from non-auth MDSs could break by triggering the "check auth cap only"
case.
Signed-off-by: Sage Weil <sage@newdream.net>
If the file mode is marked as "lazy," perform cached/buffered reads when
the caps permit it. Adjust the rdcache_gen and invalidation logic
accordingly so that we manage our cache based on the FILE_CACHE -or-
FILE_LAZYIO cap bits.
Signed-off-by: Sage Weil <sage@newdream.net>
If we have marked a file as "lazy" (using the ceph ioctl), perform buffered
writes when the MDS caps allow it.
Signed-off-by: Sage Weil <sage@newdream.net>
This fixes an issue triggered by running concurrent syncs. One of the syncs
would go through while the other would just hang indefinitely. In any case, we
never actually want to wake a single waiter, so the *_all functions should
be used.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
When we embed a dentry lease release notification in a request, invalidate
our lease so we don't think we still have it. Otherwise we can get all
sorts of incorrect client behavior when multiple clients are interacting
with the same part of the namespace.
Signed-off-by: Sage Weil <sage@newdream.net>
We need to increase the total and used counters when allocating a new cap
in the non-reserved (cap import) case.
Signed-off-by: Sage Weil <sage@newdream.net>
We can drop caps with an mds request. Ensure we only drop unused AND
clean caps, since the MDS doesn't support cap writeback in that context,
nor do we track it. If caps are dirty, and the MDS needs them back, we
it will revoke and we will flush in the normal fashion.
This fixes a possibly loss of metadata.
Signed-off-by: Sage Weil <sage@newdream.net>
If we have enough memory to allocate a new cap release message, do so, so
that we can send a partial release message immediately. This keeps us from
making the MDS wait when the cap release it needs is in a partially full
release message.
If we fail because of ENOMEM, oh well, they'll just have to wait a bit
longer.
Signed-off-by: Sage Weil <sage@newdream.net>
If we get an IMPORT that give us a cap, but we don't have the inode, queue
a release (and try to send it immediately) so that the MDS doesn't get
stuck waiting for us.
Signed-off-by: Sage Weil <sage@newdream.net>
This is essential, as for the rados block device we'll need
to run in different contexts that would need flags that
are other than GFP_NOFS.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
We only need to pass in front_len. Callers can attach any other payload
pieces (middle, data) as they see fit.
Signed-off-by: Sage Weil <sage@newdream.net>
Returning ERR_PTR(-ENOMEM) is useless extra work. Return NULL on failure
instead, and fix up the callers (about half of which were wrong anyway).
Signed-off-by: Sage Weil <sage@newdream.net>
ceph_sb_to_client and ceph_client are really identical, we need to dump
one; while function ceph_client is confusing with "struct ceph_client",
ceph_sb_to_client's definition is more clear; so we'd better switch all
call to ceph_sb_to_client.
-static inline struct ceph_client *ceph_client(struct super_block *sb)
-{
- return sb->s_fs_info;
-}
Signed-off-by: Cheng Renquan <crquan@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>
The iterate_session_caps helper traverses the session caps list and tries
to grab an inode reference. However, the __ceph_remove_cap was clearing
the inode backpointer _before_ removing itself from the session list,
causing a null pointer dereference.
Clear cap->ci under protection of s_cap_lock to avoid the race, and to
tightly couple the list and backpointer state. Use a local flag to
indicate whether we are releasing the cap, as cap->session may be modified
by a racing thread in iterate_session_caps.
Signed-off-by: Sage Weil <sage@newdream.net>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
ceph: use separate class for ceph sockets' sk_lock
ceph: reserve one more caps space when doing readdir
ceph: queue_cap_snap should always queue dirty context
ceph: fix dentry reference leak in dcache readdir
ceph: decode v5 of osdmap (pool names) [protocol change]
ceph: fix ack counter reset on connection reset
ceph: fix leaked inode ref due to snap metadata writeback race
ceph: fix snap context reference leaks
ceph: allow writeback of snapped pages older than 'oldest' snapc
ceph: fix dentry rehashing on virtual .snap dir
We create a ceph_cap_snap if there is dirty cap metadata (for writeback to
mds) OR dirty pages (for writeback to osd). It is thus possible that the
metadata has been written back to the MDS but the OSD data has not when
the cap_snap is created. This results in a cap_snap with dirty(caps) == 0.
The problem is that cap writeback to the MDS isn't necessary, and a
FLUSHSNAP cap op gets no ack from the MDS. This leaves the cap_snap
attached to the inode along with its inode reference.
Fix the problem by dropping the cap_snap if it becomes 'complete' (all
pages written out) and dirty(caps) == 0 in ceph_put_wrbuffer_cap_refs().
Also, BUG() in __ceph_flush_snaps() if we encounter a cap_snap with
dirty(caps) == 0.
Signed-off-by: Sage Weil <sage@newdream.net>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
We were releasing used caps (e.g. FILE_CACHE) from encode_inode_release
with MDS requests (e.g. setattr). We don't carry refs on most caps, so
this code worked most of the time, but for setattr (utimes) we try to
drop Fscr.
This causes cap state to get slightly out of sync with reality, and may
result in subsequent mds revoke messages getting ignored.
Fix by only releasing unused caps.
Signed-off-by: Sage Weil <sage@newdream.net>
Drop session mutex unconditionally in handle_cap_grant, and do the
check_caps from the handle_cap_grant helper. This avoids using a magic
return value.
Also avoid using a flag variable in the IMPORT case and call
check_caps at the appropriate point.
Signed-off-by: Sage Weil <sage@newdream.net>
Passing a session pointer to ceph_check_caps() used to mean it would leave
the session mutex locked. That wasn't always possible if it wasn't passed
CHECK_CAPS_AUTHONLY. If could unlock the passed session and lock a
differet session mutex, which was clearly wrong, and also emitted a
warning when it a racing CPU retook it and we did an unlock from the wrong
context.
This was only a problem when there was more than one MDS.
First, make ceph_check_caps unconditionally drop the session mutex, so that
it is free to lock other sessions as needed. Then adjust the one caller
that passes in a session (handle_cap_grant) accordingly.
Signed-off-by: Sage Weil <sage@newdream.net>
Added assertion, and cleared one case where the implemented caps were
not following the issued caps.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
