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: Ilya 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: Ilya Dryomov <idryomov@gmail.com>

Introduce __rbd_dev_header_unwatch_sync(), which doesn't flush notify
callbacks.  This is for the new rados_watcherrcb_t, which would be
called from a notify callback.
Signed-off-by: Ilya 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: Ilya Dryomov <idryomov@gmail.com>

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

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

Add and decode pi->min_size and pi->last_force_request_resend.  These
are going to be used by calc_target().
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

calc_target() code is going to need to know how to compare PGs.  Take
lhs and rhs pgid by const * while at it.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Rename ceph_calc_pg_primary() to ceph_pg_to_acting_primary() to
emphasise that it returns acting primary.
Signed-off-by: Ilya 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: Ilya 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: Ilya Dryomov <idryomov@gmail.com>

eversion_t is version+epoch in userspace and is encoded in that order.
ceph_eversion is defined as epoch+version in rados.h, yet we memcpy it
in __send_request().  Reoder ceph_eversion fields.
Signed-off-by: Ilya 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: Ilya Dryomov <idryomov@gmail.com>

They are called only once, from ceph_osdc_stop() and
handle_osds_timeout() respectively.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Either unused or useless:

    osdmap->mkfs_epoch
    osd->o_marked_for_keepalive
    monc->num_generic_requests
    osdc->map_waiters
    osdc->last_requested_map
    osdc->timeout_tid

    osd_req_op_cls_response_data()

    osdmap_apply_incremental() @msgr arg
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Switch to ceph_object_id and use ceph_oid_aprintf() instead of a bare
const char *.  This reduces noise in rbd_dev_header_name().
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Currently ceph_object_id can hold object names of up to 100
(CEPH_MAX_OID_NAME_LEN) characters.  This is enough for all use cases,
expect one - long rbd image names:

- a format 1 header is named "<imgname>.rbd"
- an object that points to a format 2 header is named "rbd_id.<imgname>"

We operate on these potentially long-named objects during rbd map, and,
for format 1 images, during header refresh.  (A format 2 header name is
a small system-generated string.)

Lift this 100 character limit by making ceph_object_id be able to point
to an externally-allocated string.  Apart from being able to work with
almost arbitrarily-long named objects, this allows us to reduce the
size of ceph_object_id from >100 bytes to 64 bytes.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

For a message pool message, preallocate a page, just like we do for
osd_op.  For a normal message, take ceph_object_id into account and
don't bother subtracting CEPH_OSD_SLAB_OPS ceph_osd_ops.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

The size of ->r_request and ->r_reply messages depends on the size of
the object name (ceph_object_id), while the size of ceph_osd_request is
fixed.  Move message allocation into a separate function that would
have to be called after ceph_object_id and ceph_object_locator (which
is also going to become variable in size with RADOS namespaces) have
been filled in:

    req = ceph_osdc_alloc_request(...);
    <fill in req->r_base_oid>
    <fill in req->r_base_oloc>
    ceph_osdc_alloc_messages(req);
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

ceph_osdc_build_request() is going away.  Grab snapc and initialize
->r_snapid in ceph_osdc_alloc_request().
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

By the time we get to checking for_each_obj_request_safe(img_request)
terminating condition, all obj_requests may be complete and img_request
ref, that rbd_img_request_submit() takes away from its caller, may be
put.  Moving the next_obj_request cursor is then a use-after-free on
img_request.

It's totally benign, as the value that's read is never used, but
I think it's still worth fixing.

Cc: Alex Elder <elder@linaro.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Pull x86 fix from Thomas Gleixner:
 "Just the missing compat entry for the new pread/writev2"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Use compat version for preadv2 and pwritev2

Pull networking fixes from David Miller:

 1) Fix mvneta/bm dependencies, from Arnd Bergmann.

 2) RX completion hw bug workaround in bnxt_en, from Michael Chan.

 3) Kernel pointer leak in nf_conntrack, from Linus.

 4) Hoplimit route attribute limits not enforced properly, from Paolo
    Abeni.

 5) qlcnic driver NULL deref fix from Dan Carpenter.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  arm64: bpf: jit JMP_JSET_{X,K}
  net/route: enforce hoplimit max value
  nf_conntrack: avoid kernel pointer value leak in slab name
  drivers: net: xgene: fix register offset
  drivers: net: xgene: fix statistics counters race condition
  drivers: net: xgene: fix ununiform latency across queues
  drivers: net: xgene: fix sharing of irqs
  drivers: net: xgene: fix IPv4 forward crash
  xen-netback: fix extra_info handling in xenvif_tx_err()
  net: mvneta: bm: fix dependencies again
  bnxt_en: Add workaround to detect bad opaque in rx completion (part 2)
  bnxt_en: Add workaround to detect bad opaque in rx completion (part 1)
  qlcnic: potential NULL dereference in qlcnic_83xx_get_minidump_template()

Original implementation commit e54bcde3 ("arm64: eBPF JIT compiler")
had the relevant code paths, but due to an oversight always fail jiting.

As a result, we had been falling back to BPF interpreter whenever a BPF
program has JMP_JSET_{X,K} instructions.

With this fix, we confirm that the corresponding tests in lib/test_bpf
continue to pass, and also jited.

...
[    2.784553] test_bpf: #30 JSET jited:1 188 192 197 PASS
[    2.791373] test_bpf: #31 tcpdump port 22 jited:1 325 677 625 PASS
[    2.808800] test_bpf: #32 tcpdump complex jited:1 323 731 991 PASS
...
[    3.190759] test_bpf: #237 JMP_JSET_K: if (0x3 & 0x2) return 1 jited:1 110 PASS
[    3.192524] test_bpf: #238 JMP_JSET_K: if (0x3 & 0xffffffff) return 1 jited:1 98 PASS
[    3.211014] test_bpf: #249 JMP_JSET_X: if (0x3 & 0x2) return 1 jited:1 120 PASS
[    3.212973] test_bpf: #250 JMP_JSET_X: if (0x3 & 0xffffffff) return 1 jited:1 89 PASS
...

Fixes: e54bcde3 ("arm64: eBPF JIT compiler")
Signed-off-by: Zi Shen Lim <zlim.lnx@gmail.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently, when creating or updating a route, no check is performed
in both ipv4 and ipv6 code to the hoplimit value.

The caller can i.e. set hoplimit to 256, and when such route will
 be used, packets will be sent with hoplimit/ttl equal to 0.

This commit adds checks for the RTAX_HOPLIMIT value, in both ipv4
ipv6 route code, substituting any value greater than 255 with 255.

This is consistent with what is currently done for ADVMSS and MTU
in the ipv4 code.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The slab name ends up being visible in the directory structure under
/sys, and even if you don't have access rights to the file you can see
the filenames.

Just use a 64-bit counter instead of the pointer to the 'net' structure
to generate a unique name.

This code will go away in 4.7 when the conntrack code moves to a single
kmemcache, but this is the backportable simple solution to avoiding
leaking kernel pointers to user space.

Fixes: 5b3501fa ("netfilter: nf_conntrack: per netns nf_conntrack_cachep")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>