Initializing debufs under monc->mutex introduces a lock dependency for
sb->s_type->i_mutex_key, which (combined with several other dependencies)
leads to an annoying lockdep warning. There's no particular reason to do
the debugfs setup under this lock, so move it out.
It used to be the case that our first monmap could come from the OSD; that
is no longer the case with recent servers, so we will reliably set up the
client entry during the initial authentication.
We don't have to worry about racing with debugfs teardown by
ceph_debugfs_client_cleanup() because ceph_destroy_client() calls
ceph_msgr_flush() first, which will wait for the message dispatch work
to complete (and the debugfs init to complete).
Fixes: #1940
Signed-off-by: Sage Weil <sage@newdream.net>
Use kmemdup rather than duplicating its implementation
The semantic patch that makes this change is available
in scripts/coccinelle/api/memdup.cocci.
Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Sage Weil <sage@newdream.net>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
ceph: add missing spin_unlock at ceph_mdsc_build_path()
ceph: fix SEEK_CUR, SEEK_SET regression
crush: fix mapping calculation when force argument doesn't exist
ceph: use i_ceph_lock instead of i_lock
rbd: remove buggy rollback functionality
rbd: return an error when an invalid header is read
ceph: fix rasize reporting by ceph_show_options
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
libceph: Allocate larger oid buffer in request msgs
ceph: initialize root dentry
ceph: fix iput race when queueing inode work
ceph_osd_request struct allocates a 40-byte buffer for object names.
RBD image names can be up to 96 chars long (100 with the .rbd suffix),
which results in the object name for the image being truncated, and a
subsequent map failure.
Increase the oid buffer in request messages, in order to avoid the
truncation.
Signed-off-by: Stratos Psomadakis <psomas@grnet.gr>
Signed-off-by: Sage Weil <sage@newdream.net>
These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things won't break when we remove the implicit presence
of module.h from everywhere.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
If we skip over one or more map epochs, we need to resend all osd requests
because it is possible they remapped to other servers and then back.
Signed-off-by: Sage Weil <sage@newdream.net>
Change ceph_parse_ips to take either names given as
IP addresses or standard hostnames (e.g. localhost).
The DNS lookup is done using the dns_resolver facility
similar to its use in AFS, NFS, and CIFS.
This patch defines CONFIG_CEPH_LIB_USE_DNS_RESOLVER
that controls if this feature is on or off.
Signed-off-by: Noah Watkins <noahwatkins@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>
Any non-masked msg allocation failure should generate a warning and stack
trace to the console. All of these need to eventually be replaced by
safe preallocation or msgpools.
Signed-off-by: Sage Weil <sage@newdream.net>
The pool allocation failures are masked by the pool; there is no need to
spam the console about them. (That's the whole point of having the pool
in the first place.)
Mark msg allocations whose failure is safely handled as such.
Signed-off-by: Sage Weil <sage@newdream.net>
Allocate the mon connection on init. We already reuse it across
reconnects. Remove now unnecessary (and incomplete) NULL checks.
Signed-off-by: Sage Weil <sage@newdream.net>
This simplifies the init/shutdown paths, and makes client->msgr available
during the rest of the setup process.
Signed-off-by: Sage Weil <sage@newdream.net>
The incremental map updates have a record for each pg_temp mapping that is
to be add/updated (len > 0) or removed (len == 0). The old code was
written as if the updates were a complete enumeration; that was just wrong.
Update the code to remove 0-length entries and drop the rbtree traversal.
This avoids misdirected (and hung) requests that manifest as server
errors like
[WRN] client4104 10.0.1.219:0/275025290 misdirected client4104.1:129 0.1 to osd0 not [1,0] in e11/11
Signed-off-by: Sage Weil <sage@newdream.net>
We need to apply the modulo pg_num calculation before looking up a pgid in
the pg_temp mapping rbtree. This fixes pg_temp mappings, and fixes
(some) misdirected requests that result in messages like
[WRN] client4104 10.0.1.219:0/275025290 misdirected client4104.1:129 0.1 to osd0 not [1,0] in e11/11
on the server and stall make the client block without getting a reply (at
least until the pg_temp mapping goes way, but that can take a long long
time).
Reorder calc_pg_raw() a bit to make more sense.
Signed-off-by: Sage Weil <sage@newdream.net>
The r_req_lru_item list node moves between several lists, and that cycle
is not directly related (and does not begin) with __register_request().
Initialize it in the request constructor, not __register_request(). This
fixes later badness (below) when OSDs restart underneath an rbd mount.
Crashes we've seen due to this include:
[ 213.974288] kernel BUG at net/ceph/messenger.c:2193!
and
[ 144.035274] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048
[ 144.035278] IP: [<ffffffffa036c053>] con_work+0x1463/0x2ce0 [libceph]
Signed-off-by: Sage Weil <sage@newdream.net>
ceph_destroy_options does not free opt->mon_addr that
is allocated in ceph_parse_options.
Signed-off-by: Noah Watkins <noahwatkins@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>
Commit 4cf9d54463 recorded when an outgoing ceph message was ACKed,
in order to avoid unnecessary connection resets when an OSD is busy.
However, ack_stamp is uninitialized, so there is a window between
when the message is sent and when it is ACKed in which handle_timeout()
interprets the unitialized value as an expired timeout, and resets
the connection unnecessarily.
Close the window by initializing ack_stamp.
Signed-off-by: Jim Schutt <jaschut@sandia.gov>
Signed-off-by: Sage Weil <sage@newdream.net>
There were several problems here:
1- we weren't tagging allocations with the pool, so they were never
returned to the pool.
2- msgpool_put didn't add back to the mempool, even it were called.
3- msgpool_release didn't clear the pool pointer, so it would have looped
had #1 not been broken.
These may or may not have been responsible for #1136 or #1381 (BUG due to
non-empty mempool on umount). I can't seem to trigger the crash now using
the method I was using before.
Signed-off-by: Sage Weil <sage@newdream.net>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (23 commits)
ceph: document unlocked d_parent accesses
ceph: explicitly reference rename old_dentry parent dir in request
ceph: document locking for ceph_set_dentry_offset
ceph: avoid d_parent in ceph_dentry_hash; fix ceph_encode_fh() hashing bug
ceph: protect d_parent access in ceph_d_revalidate
ceph: protect access to d_parent
ceph: handle racing calls to ceph_init_dentry
ceph: set dir complete frag after adding capability
rbd: set blk_queue request sizes to object size
ceph: set up readahead size when rsize is not passed
rbd: cancel watch request when releasing the device
ceph: ignore lease mask
ceph: fix ceph_lookup_open intent usage
ceph: only link open operations to directory unsafe list if O_CREAT|O_TRUNC
ceph: fix bad parent_inode calc in ceph_lookup_open
ceph: avoid carrying Fw cap during write into page cache
libceph: don't time out osd requests that haven't been received
ceph: report f_bfree based on kb_avail rather than diffing.
ceph: only queue capsnap if caps are dirty
ceph: fix snap writeback when racing with writes
...
Keep track of when an outgoing message is ACKed (i.e., the server fully
received it and, presumably, queued it for processing). Time out OSD
requests only if it's been too long since they've been received.
This prevents timeouts and connection thrashing when the OSDs are simply
busy and are throttling the requests they read off the network.
Reviewed-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
open(2) must always include one of O_RDONLY, O_WRONLY, or O_RDWR. No need
for any O_APPEND special case.
Passing O_WRONLY|O_RDWR is undefined according to the man page, but the
Linux VFS interprets this as O_RDWR, so we'll do the same.
This fixes open(2) with flags O_RDWR|O_APPEND, which was incorrectly being
translated to readonly.
Reported-by: Fyodor Ustinov <ufm@ufm.su>
Signed-off-by: Sage Weil <sage@newdream.net>
Unnecessary casts of void * clutter the code.
These are the remainder casts after several specific
patches to remove netdev_priv and dev_priv.
Done via coccinelle script:
$ cat cast_void_pointer.cocci
@@
type T;
T *pt;
void *pv;
@@
- pt = (T *)pv;
+ pt = pv;
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@conan.davemloft.net>
Set the page count correctly for non-page-aligned IO. We were already
doing this correctly for alignment, but not the page count. Fixes
DIRECT_IO writes from unaligned pages.
Signed-off-by: Sage Weil <sage@newdream.net>
If we cancel a write, trigger the safe completions to prevent a sync from
blocking indefinitely in ceph_osdc_sync().
Signed-off-by: Sage Weil <sage@newdream.net>
When the cluster is marked full, subscribe to subsequent map updates to
ensure we find out promptly when it is no longer full. This will prevent
us from spewing ENOSPC for (much) longer than necessary.
Signed-off-by: Sage Weil <sage@newdream.net>
Old incrementals encode a 0 value (nearly always) when an osd goes down.
Change that to allow any state bit(s) to be flipped. Special case 0 to
mean flip the CEPH_OSD_UP bit to mimic the old behavior.
Signed-off-by: Sage Weil <sage@newdream.net>
Since we pass the nofail arg, we should never get an error; BUG if we do.
(And fix the function to not return an error if __map_request fails.)
Signed-off-by: Sage Weil <sage@newdream.net>
If we get a WAIT as a client something went wrong; error out. And don't
fall through to an unrelated case.
Signed-off-by: Sage Weil <sage@newdream.net>
If there is no get_authorizer method we set the out_kvec to a bogus
pointer. The length is also zero in that case, so it doesn't much matter,
but it's better not to add the empty item in the first place.
Signed-off-by: Sage Weil <sage@newdream.net>
If a connection is closed and/or reopened (ceph_con_close, ceph_con_open)
it can race with a callback. con_work does various state checks for
closed or reopened sockets at the beginning, but drops con->mutex before
making callbacks. We need to check for state bit changes after retaking
the lock to ensure we restart con_work and execute those CLOSED/OPENING
tests or else we may end up operating under stale assumptions.
In Jim's case, this was causing 'bad tag' errors.
There are four cases where we re-take the con->mutex inside con_work: catch
them all and return EAGAIN from try_{read,write} so that we can restart
con_work.
Reported-by: Jim Schutt <jaschut@sandia.gov>
Tested-by: Jim Schutt <jaschut@sandia.gov>
Signed-off-by: Sage Weil <sage@newdream.net>
If memory allocation failed, calling ceph_msg_put() will cause GPF
since some of ceph_msg variables are not initialized first.
Fix Bug #970.
Signed-off-by: Henry C Chang <henry_c_chang@tcloudcomputing.com>
Signed-off-by: Sage Weil <sage@newdream.net>
Fix the request transition from linger -> normal request. The key is to
preserve r_osd and requeue on the same OSD. Reregister as a normal request,
add the request to the proper queues, then unregister the linger. Fix the
unregister helper to avoid clearing r_osd (and also simplify the parallel
check in __unregister_request()).
Reported-by: Henry Chang <henry.cy.chang@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>
This allows us to use existence of the key type as a feature test,
from userspace.
Signed-off-by: Tommi Virtanen <tommi.virtanen@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>
This makes the base64 logic be contained in mount option parsing,
and prepares us for replacing the homebew key management with the
kernel key retention service.
Signed-off-by: Tommi Virtanen <tommi.virtanen@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>
We should only clear r_osd if we are neither registered as a linger or a
regular request. We may unregister as a linger while still registered as
a regular request (e.g., in reset_osd). Incorrectly clearing r_osd there
leads to a null pointer dereference in __send_request.
Also simplify the parallel check in __unregister_request() where we just
removed r_osd_item and know it's empty.
Signed-off-by: Sage Weil <sage@newdream.net>
There was a missing unlock on the error path if __map_request() failed.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>
This patch fixes 'event_work' dereference before it is checked for NULL.
Signed-off-by: Mariusz Kozlowski <mk@lab.zgora.pl>
Signed-off-by: Sage Weil <sage@newdream.net>
The release method for mds connections uses a backpointer to the
mds_client, so we need to flush the workqueue of any pending work (and
ceph_connection references) prior to freeing the mds_client. This fixes
an oops easily triggered under UML by
while true ; do mount ... ; umount ... ; done
Also fix an outdated comment: the flush in ceph_destroy_client only flushes
OSD connections out. This bug is basically an artifact of the ceph ->
ceph+libceph conversion.
Signed-off-by: Sage Weil <sage@newdream.net>
Lingering requests are requests that are sent to the OSD normally but
tracked also after we get a successful request. This keeps the OSD
connection open and resends the original request if the object moves to
another OSD. The OSD can then send notification messages back to us
if another client initiates a notify.
This framework will be used by RBD so that the client gets notification
when a snapshot is created by another node or tool.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
If we send a request to osd A, and the request's pg remaps to osd B and
then back to A in quick succession, we need to resend the request to A. The
old code was only calling kick_requests after processing all incremental
maps in a message, so it was very possible to not resend a request that
needed to be resent. This would make the osd eventually time out (at least
with the current default of osd timeouts enabled).
The correct approach is to scan requests on every map incremental. This
patch refactors the kick code in a few ways:
- all requests are either on req_lru (in flight), req_unsent (ready to
send), or req_notarget (currently map to no up osd)
- mapping always done by map_request (previous map_osds)
- if the mapping changes, we requeue. requests are resent only after all
map incrementals are processed.
- some osd reset code is moved out of kick_requests into a separate
function
- the "kick this osd" functionality is moved to kick_osd_requests, as it
is unrelated to scanning for request->pg->osd mapping changes
Signed-off-by: Sage Weil <sage@newdream.net>
It used to return -EINVAL because it thought the end was not aligned
to 4 bytes.
Clean up superfluous src < end test in if, the while itself guarantees
that.
Signed-off-by: Tommi Virtanen <tommi.virtanen@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>
The standby logic used to be pretty dependent on the work requeueing
behavior that changed when we switched to WQ_NON_REENTRANT. It was also
very fragile.
Restructure things so that:
- We clear WRITE_PENDING when we set STANDBY. This ensures we will
requeue work when we wake up later.
- con_work backs off if STANDBY is set. There is nothing to do if we are
in standby.
- clear_standby() helper is called by both con_send() and con_keepalive(),
the two actions that can wake us up again. Move the connect_seq++
logic here.
Signed-off-by: Sage Weil <sage@newdream.net>
With commit f363e45f we replaced a bunch of hacky workqueue mutual
exclusion logic with the WQ_NON_REENTRANT flag. One pieces of fallout is
that the exponential backoff breaks in certain cases:
* con_work attempts to connect.
* we get an immediate failure, and the socket state change handler queues
immediate work.
* con_work calls con_fault, we decide to back off, but can't queue delayed
work.
In this case, we add a BACKOFF bit to make con_work reschedule delayed work
next time it runs (which should be immediately).
Signed-off-by: Sage Weil <sage@newdream.net>
If we mark the connection CLOSED we will give up trying to reconnect to
this server instance. That is appropriate for things like a protocol
version mismatch that won't change until the server is restarted, at which
point we'll get a new addr and reconnect. An authorization failure like
this is probably due to the server not properly rotating it's secret keys,
however, and should be treated as transient so that the normal backoff and
retry behavior kicks in.
Signed-off-by: Sage Weil <sage@newdream.net>
get_user_pages() can return fewer pages than we ask for. We were returning
a bogus pointer/error code in that case. Instead, loop until we get all
the pages we want or get an error we can return to the caller.
Signed-off-by: Sage Weil <sage@newdream.net>
Pass errors from writing to the socket up the stack. If we get -EAGAIN,
return 0 from the helper to simplify the callers' checks.
Signed-off-by: Sage Weil <sage@newdream.net>
If we get EAGAIN when trying to read from the socket, it is not an error.
Return 0 from the helper in this case to simplify the error handling cases
in the caller (indirectly, try_read).
Fix try_read to pass any error to it's caller (con_work) instead of almost
always returning 0. This let's us respond to things like socket
disconnects.
Signed-off-by: Sage Weil <sage@newdream.net>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
rbd: fix cleanup when trying to mount inexistent image
net/ceph: make ceph_msgr_wq non-reentrant
ceph: fsc->*_wq's aren't used in memory reclaim path
ceph: Always free allocated memory in osdmap_decode()
ceph: Makefile: Remove unnessary code
ceph: associate requests with opening sessions
ceph: drop redundant r_mds field
ceph: implement DIRLAYOUTHASH feature to get dir layout from MDS
ceph: add dir_layout to inode
ceph messenger code does a rather complex dancing around multithread
workqueue to make sure the same work item isn't executed concurrently
on different CPUs. This restriction can be provided by workqueue with
WQ_NON_REENTRANT.
Make ceph_msgr_wq non-reentrant workqueue with the default concurrency
level and remove the QUEUED/BUSY logic.
* This removes backoff handling in con_work() but it couldn't reliably
block execution of con_work() to begin with - queue_con() can be
called after the work started but before BUSY is set. It seems that
it was an optimization for a rather cold path and can be safely
removed.
* The number of concurrent work items is bound by the number of
connections and connetions are independent from each other. With
the default concurrency level, different connections will be
executed independently.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Sage Weil <sage@newdream.net>
Cc: ceph-devel@vger.kernel.org
Signed-off-by: Sage Weil <sage@newdream.net>
Add a ceph_dir_layout to the inode, and calculate dentry hash values based
on the parent directory's specified dir_hash function. This is needed
because the old default Linux dcache hash function is extremely week and
leads to a poor distribution of files among dir fragments.
Signed-off-by: Sage Weil <sage@newdream.net>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
ceph: handle partial result from get_user_pages
ceph: mark user pages dirty on direct-io reads
ceph: fix null pointer dereference in ceph_init_dentry for nfs reexport
ceph: fix direct-io on non-page-aligned buffers
ceph: fix msgr_init error path
The get_user_pages() helper can return fewer than the requested pages.
Error out in that case, and clean up the partial result.
Signed-off-by: Henry C Chang <henry_c_chang@tcloudcomputing.com>
Signed-off-by: Sage Weil <sage@newdream.net>
For read operation, we have to set the argument _write_ of get_user_pages
to 1 since we will write data to pages. Also, we need to SetPageDirty before
releasing these pages.
Signed-off-by: Henry C Chang <henry_c_chang@tcloudcomputing.com>
Signed-off-by: Sage Weil <sage@newdream.net>
Remove the if and else conditional because the code is in mainline and there
is no need in it being there.
Signed-off-by: Tracey Dent <tdent48227@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
of/phylib: Use device tree properties to initialize Marvell PHYs.
phylib: Add support for Marvell 88E1149R devices.
phylib: Use common page register definition for Marvell PHYs.
qlge: Fix incorrect usage of module parameters and netdev msg level
ipv6: fix missing in6_ifa_put in addrconf
SuperH IrDA: correct Baud rate error correction
atl1c: Fix hardware type check for enabling OTP CLK
net: allow GFP_HIGHMEM in __vmalloc()
bonding: change list contact to netdev@vger.kernel.org
e1000: fix screaming IRQ
Changed Makefile to use <modules>-y instead of <modules>-objs
because -objs is deprecated and not mentioned in
Documentation/kbuild/makefiles.txt.
Signed-off-by: Tracey Dent <tdent48227@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We forgot to use __GFP_HIGHMEM in several __vmalloc() calls.
In ceph, add the missing flag.
In fib_trie.c, xfrm_hash.c and request_sock.c, using vzalloc() is
cleaner and allows using HIGHMEM pages as well.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The alignment used for reading data into or out of pages used to be taken
from the data_off field in the message header. This only worked as long
as the page alignment matched the object offset, breaking direct io to
non-page aligned offsets.
Instead, explicitly specify the page alignment next to the page vector
in the ceph_msg struct, and use that instead of the message header (which
probably shouldn't be trusted). The alloc_msg callback is responsible for
filling in this field properly when it sets up the page vector.
Signed-off-by: Sage Weil <sage@newdream.net>
We used to infer alignment of IOs within a page based on the file offset,
which assumed they matched. This broke with direct IO that was not aligned
to pages (e.g., 512-byte aligned IO). We were also trusting the alignment
specified in the OSD reply, which could have been adjusted by the server.
Explicitly specify the page alignment when setting up OSD IO requests.
Signed-off-by: Sage Weil <sage@newdream.net>
If the client gets out of sync with the server message sequence number, we
normally skip low seq messages (ones we already received). The skip code
was also incrementing the expected seq, such that all subsequent messages
also appeared old and got skipped, and an eventual timeout on the osd
connection. This resulted in some lagging requests and console messages
like
[233480.882885] ceph: skipping osd22 10.138.138.13:6804 seq 2016, expected 2017
[233480.882919] ceph: skipping osd22 10.138.138.13:6804 seq 2017, expected 2018
[233480.882963] ceph: skipping osd22 10.138.138.13:6804 seq 2018, expected 2019
[233480.883488] ceph: skipping osd22 10.138.138.13:6804 seq 2019, expected 2020
[233485.219558] ceph: skipping osd22 10.138.138.13:6804 seq 2020, expected 2021
[233485.906595] ceph: skipping osd22 10.138.138.13:6804 seq 2021, expected 2022
[233490.379536] ceph: skipping osd22 10.138.138.13:6804 seq 2022, expected 2023
[233495.523260] ceph: skipping osd22 10.138.138.13:6804 seq 2023, expected 2024
[233495.923194] ceph: skipping osd22 10.138.138.13:6804 seq 2024, expected 2025
[233500.534614] ceph: tid 6023602 timed out on osd22, will reset osd
Reported-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sage Weil <sage@newdream.net>
This only happened when parse_extra_token was not passed
to ceph_parse_option() (hence, only happened in rbd).
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
These facilitate preallocation of pages so that we can encode into the pagelist
in an atomic context.
Signed-off-by: Greg Farnum <gregf@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
The rados block device (rbd), based on osdblk, creates a block device
that is backed by objects stored in the Ceph distributed object storage
cluster. Each device consists of a single metadata object and data
striped over many data objects.
The rbd driver supports read-only snapshots.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
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>
