To spare checking for "this reply fits into a page, but does it fit
into my buffer?" in some callers, osd_req_op_cls_response_data_pages()
needs to know how big it is.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Reviewed-by: NJason Dillaman <dillaman@redhat.com>

add_to_page_cache_lru() can fails, so the actual pages to read
can be smaller than the initial size of osd request. We need to
update osd request size in that case.
Signed-off-by: NYan, Zheng <zyan@redhat.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>

Kill the wrapper and rename __finish_request() to finish_request().
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

r_safe_completion is currently, and has always been, signaled only if
on-disk ack was requested.  It's there for fsync and syncfs, which wait
for in-flight writes to flush - all data write requests set ONDISK.

However, the pool perm check code introduced in 4.2 sends a write
request with only ACK set.  An unfortunately timed syncfs can then hang
forever: r_safe_completion won't be signaled because only an unsafe
reply was requested.

We could patch ceph_osdc_sync() to skip !ONDISK write requests, but
that is somewhat incomplete and yet another special case.  Instead,
rename this completion to r_done_completion and always signal it when
the OSD client is done with the request, whether unsafe, safe, or
error.  This is a bit cleaner and helps with the cancellation code.
Reported-by: NYan, Zheng <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

The length of the reply is protocol-dependent - for cephx it's
ceph_x_authorize_reply.  Nothing sensible can be passed from the
messenger layer anyway.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Reviewed-by: NSage Weil <sage@redhat.com>

osdc->last_linger_id is a counter for lreq->linger_id, which is used
for watch cookies.  Starting with a large integer should ease the task
of telling apart kernel and userspace clients.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Revamp watch code to support retrying watch re-registration:

- add rbd_dev->watch_state for more robust errcb handling
- store watch cookie separately to avoid dereferencing watch_handle
  which is set to NULL on unwatch
- move re-register code into a delayed work and retry re-registration
  every second, unless the client is blacklisted
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Tested-by: NMike Christie <mchristi@redhat.com>

Add a convenience function to osd_client to send Ceph OSD
'class' ops. The interface assumes that the request and
reply data each consist of single pages.
Signed-off-by: NDouglas Fuller <dfuller@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Reviewed-by: NAlex Elder <elder@linaro.org>

Add support for this Ceph OSD op, needed to support the RBD exclusive
lock feature.
Signed-off-by: NDouglas Fuller <dfuller@redhat.com>
[idryomov@gmail.com: refactor, misc fixes throughout]
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Reviewed-by: NAlex Elder <elder@linaro.org>

In case of error, the function ceph_alloc_page_vector() returns
ERR_PTR() and never returns NULL. The NULL test in the return value
check should be replaced with IS_ERR().

Fixes: 19079203 ('libceph: support for sending notifies')
Signed-off-by: NWei Yongjun <weiyj.lk@gmail.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Signed-off-by: NYan, Zheng <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Add pool namesapce pointer to struct ceph_file_layout and struct
ceph_object_locator. Pool namespace is used by when mapping object
to PG, it's also used when composing OSD request.

The namespace pointer in struct ceph_file_layout is RCU protected.
So libceph can read namespace without taking lock.
Signed-off-by: NYan, Zheng <zyan@redhat.com>
[idryomov@gmail.com: ceph_oloc_destroy(), misc minor changes]
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Define new ceph_file_layout structure and rename old ceph_file_layout
to ceph_file_layout_legacy. This is preparation for adding namespace
to ceph_file_layout structure.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

Commit d30291b9 ("libceph: variable-sized ceph_object_id") changed
dout()s in what is now encode_request() and ceph_object_locator_to_pg()
to use %pE, mostly to document that, although all rbd and cephfs object
names are NULL-terminated strings, ceph_object_id will handle any RADOS
object name, including the one containing NULs, just fine.

However, it turns out that vbin_printf() can't handle anything but ints
and %s - all %p suffixes are ignored.  The buffer %p** points to isn't
recorded, resulting in trash in the messages if the buffer had been
reused by the time bstr_printf() got to it.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

handle_reply() may be called twice on the same request: on ack and then
on commit.  This occurs on btrfs-formatted OSDs or if cephfs sync write
path is triggered - CEPH_OSD_FLAG_ACK | CEPH_OSD_FLAG_ONDISK.

handle_reply() handles this with the help of done_request().

Fixes: 5aea3dcd ("libceph: a major OSD client update")
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

For the benefit of every single caller, take osdc instead of map.
Also, now that osdc->osdmap can't ever be NULL, drop the check.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Ceph_osdc_wait_request() is used when cephfs issues sync IO. In most
cases, the sync IO should be uninterruptible. The fix is use killale
wait function in ceph_osdc_wait_request().
Signed-off-by: NYan, Zheng <zyan@redhat.com>

... with a wrapper around maybe_request_map() - no need for two
osdmap-specific functions.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

This adds the "map check" infrastructure for sending osdmap version
checks on CALC_TARGET_POOL_DNE and completing in-flight requests with
-ENOENT if the target pool doesn't exist or has just been deleted.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Implement ceph_osdc_watch_check() to be able to check on status of
watch.  Note that the time it takes for a watch/notify event to get
delivered through the notify_wq is taken into account.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Implement ceph_osdc_notify() for sending notifies.

Due to the fact that the current messenger can't do read-in into
pagelists (it can only do write-out from them), I had to go with a page
vector for a NOTIFY_COMPLETE payload, for now.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

This adds support and switches rbd to a new, more reliable version of
watch/notify protocol.  As with the OSD client update, this is mostly
about getting the right structures linked into the right places so that
reconnects are properly sent when needed.  watch/notify v2 also
requires sending regular pings to the OSDs - send_linger_ping().

A major change from the old watch/notify implementation is the
introduction of ceph_osd_linger_request - linger requests no longer
piggy back on ceph_osd_request.  ceph_osd_event has been merged into
ceph_osd_linger_request.

All the details are now hidden within libceph, the interface consists
of a simple pair of watch/unwatch functions and ceph_osdc_notify_ack().
ceph_osdc_watch() does return ceph_osd_linger_request, but only to keep
the lifetime management simple.

ceph_osdc_notify_ack() accepts an optional data payload, which is
relayed back to the notifier.

Portions of this patch are loosely based on work by Douglas Fuller
<dfuller@redhat.com> and Mike Christie <michaelc@cs.wisc.edu>.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

The unwatch timeout is currently implemented in rbd.  With
watch/unwatch code moving into libceph, we are going to need
a ceph_osdc_wait_request() variant with a timeout.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

These are going to be used by request_reinit() code.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

This is a major sync up, up to ~Jewel.  The highlights are:

- per-session request trees (vs a global per-client tree)
- per-session locking (vs a global per-client rwlock)
- homeless OSD session
- no ad-hoc global per-client lists
- support for pool quotas
- foundation for watch/notify v2 support
- foundation for map check (pool deletion detection) support

The switchover is incomplete: lingering requests can be setup and
teared down but aren't ever reestablished.  This functionality is
restored with the introduction of the new lingering infrastructure
(ceph_osd_linger_request, linger_work, etc) in a later commit.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

OSD client is getting moved from the big per-client lock to a set of
per-session locks.  The big rwlock would only be held for read most of
the time, so a global osdc->osd_lru needs additional protection.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

create_osd() is called way too deep in the stack to be able to error
out in a sane way; a failing create_osd() just messes everything up.
The current req_notarget list solution is broken - the list is never
traversed as it's not entirely clear when to do it, I guess.

If we were to start traversing it at regular intervals and retrying
each request, we wouldn't be far off from what __GFP_NOFAIL is doing,
so allocate OSD sessions with __GFP_NOFAIL, at least until we come up
with a better fix.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

These are going to be used by homeless OSD sessions code.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Separate osdmap handling from decoding and iterating over a bag of maps
in a fresh MOSDMap message.  This sets up the scene for the updated OSD
client.

Of particular importance here is the addition of pi->was_full, which
can be used to answer "did this pool go full -> not-full in this map?".
This is the key bit for supporting pool quotas.

We won't be able to downgrade map_sem for much longer, so drop
downgrade_write().
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

This leads to a simpler osdmap handling code, particularly when dealing
with pi->was_full, which is introduced in a later commit.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Both homeless OSD sessions and watch/notify v2, introduced in later
commits, require periodic ticks which don't depend on ->num_requests.
Schedule the initial tick from ceph_osdc_init() and reschedule from
handle_timeout() unconditionally.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

ceph_osdc_stop() isn't called if ceph_osdc_init() fails, so we end up
with handle_osds_timeout() running on invalid memory if any one of the
allocations fails.  Call schedule_delayed_work() after everything is
setup, just before returning.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

If you specify ACK | ONDISK and set ->r_unsafe_callback, both
->r_callback and ->r_unsafe_callback(true) are called on ack.  This is
very confusing.  Redo this so that only one of them is called:

    ->r_unsafe_callback(true), on ack
    ->r_unsafe_callback(false), on commit

or

    ->r_callback, on ack|commit

Decode everything in decode_MOSDOpReply() to reduce clutter.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

finish_read(), its only user, uses it to get to hdr.data_len, which is
what ->r_result is set to on success.  This gains us the ability to
safely call callbacks from contexts other than reply, e.g. map check.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

The crux of this is getting rid of ceph_osdc_build_request(), so that
MOSDOp can be encoded not before but after calc_target() calculates the
actual target.  Encoding now happens within ceph_osdc_start_request().

Also nuked is the accompanying bunch of pointers into the encoded
buffer that was used to update fields on each send - instead, the
entire front is re-encoded.  If we want to support target->name_len !=
base->name_len in the future, there is no other way, because oid is
surrounded by other fields in the encoded buffer.

Encoding OSD ops and adding data items to the request message were
mixed together in osd_req_encode_op().  While we want to re-encode OSD
ops, we don't want to add duplicate data items to the message when
resending, so all call to ceph_osdc_msg_data_add() are factored out
into a new setup_request_data().
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Replace __calc_request_pg() and most of __map_request() with
calc_target() and start using req->r_t.

ceph_osdc_build_request() however still encodes base_oid, because it's
called before calc_target() is and target_oid is empty at that point in
time; a printf in osdc_show() also shows base_oid.  This is fixed in
"libceph: switch to calc_target(), part 2".
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Introduce ceph_osd_request_target, containing all mapping-related
fields of ceph_osd_request and calc_target() for calculating mappings
and populating it.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Knowning just acting set isn't enough, we need to be able to record up
set as well to detect interval changes.  This means returning (up[],
up_len, up_primary, acting[], acting_len, acting_primary) and passing
it around.  Introduce and switch to ceph_osds to help with that.

Rename ceph_calc_pg_acting() to ceph_pg_to_up_acting_osds() and return
both up and acting sets from it.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Rename ceph_oloc_oid_to_pg() to ceph_object_locator_to_pg().  Emphasise
that returned is raw PG and return -ENOENT instead of -EIO if the pool
doesn't exist.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Given

    struct foo {
        u64 id;
        struct rb_node bar_node;
    };

generate insert_bar(), erase_bar() and lookup_bar() functions with

    DEFINE_RB_FUNCS(bar, struct foo, id, bar_node)

The key is assumed to be an integer (u64, int, etc), compared with
< and >.  nodefld has to be initialized with RB_CLEAR_NODE().

Start using it for MDS, MON and OSD requests and OSD sessions.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>