GCC9 is throwing a lot of warnings about unaligned accesses by
callers of ceph_pr_addr. All of the current callers are passing a
pointer to the sockaddr inside struct ceph_entity_addr.
Fix it to take a pointer to a struct ceph_entity_addr instead,
and then have the function make a copy of the sockaddr before
printing it.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
clang complains about assigning a variable to itself during the
declaration:
fs/ceph/ioctl.c:187:26: error: variable 'oid' is uninitialized when used within its own initialization [-Werror,-Wuninitialized]
CEPH_DEFINE_OID_ONSTACK(oid);
^~~
include/linux/ceph/osdmap.h:122:52: note: expanded from macro 'CEPH_DEFINE_OID_ONSTACK'
struct ceph_object_id oid = CEPH_OID_INIT_ONSTACK(oid)
~~~ ^~~
include/linux/ceph/osdmap.h:120:29: note: expanded from macro 'CEPH_OID_INIT_ONSTACK'
({ ceph_oid_init(&oid); oid; })
^~~
We use this trick in other places, but it is completely unnecessary
here, as we can just use a regular struct initializer.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
To support snapshot nfs re-export, we need a way to lookup snapped
inode by file handle. For directory inode, snapped metadata are always
stored together with head inode. Client just need to pass vinodeno_t
to MDS. For non-directory inode, there can be multiple version of
snapped inodes and they can be stored in different dirfrags. Besides
vinodeno_t, client also need to tell mds from which dirfrag it got the
snapped inode.
Another problem of supporting snapshot nfs re-export is that there
can be multiple paths to access a snapped inode. For example:
mkdir -p d1/d2/d3
mkdir d1/.snap/s1
Paths 'd1/.snap/s1/d2/d3', 'd1/d2/.snap/_s1_<inode number of d1>/d3'
and 'd1/d2/d3/.snap/_s1_<inode number of d1>' are all reference to the
same snapped inode. For a given snapped inode, There is no convenient
way to get the first form and the second form paths. For simplicity,
ceph_get_parent() return snapdir for snapped directory inode.
Furthermore, client may access snapshot of deleted directory. For
example:
mkdir -p d1/d2
mkdir d1/.snap/s1
open d1/.snap/s1/d2
rm -rf d1/d2
<nfs server restart>
The path constucted by ceph_get_parent() and ceph_get_name() is
'<inode of d2>/.snap/_s1_<inode number of d1>'. Futher lookup parent
of <inode of d2> will fail. To workaround this case, this patch uses
d_obtain_root() to get dentry for snapdir of deleted directory.
snapdir dentry has no DCACHE_DISCONNECTED flag set, reconnect_path()
stops when it reaches snapdir dentry.
Link: http://tracker.ceph.com/issues/22105
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Because map updates are distributed lazily, an OSD may not know about
the new blacklist for quite some time after "osd blacklist add" command
is completed. This makes it possible for a blacklisted but still alive
client to overwrite a post-blacklist update, resulting in data
corruption.
Waiting for latest osdmap in ceph_monc_blacklist_add() and thus using
the post-blacklist epoch for all post-blacklist requests ensures that
all such requests "wait" for the blacklist to come into force on their
respective OSDs.
Cc: stable@vger.kernel.org
Fixes: 6305a3b415 ("libceph: support for blacklisting clients")
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jason Dillaman <dillaman@redhat.com>
If number of caps exceed the limit, ceph_trim_dentires() also trim
dentries with valid leases. Trimming dentry releases references to
associated inode, which may evict inode and release caps.
By default, there is no limit for caps count.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Introduce a new option abort_on_full, default to false. Then
we can get -ENOSPC when the pool is full, or reaches quota.
[ Don't show abort_on_full in /proc/mounts. ]
Signed-off-by: Dongsheng Yang <dongsheng.yang@easystack.cn>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
No one is running pre-argonaut. In addition one of the argonaut
features (NOSRCADDR) has been required since day one (and a half,
2.6.34 vs 2.6.35) of the kernel client.
Allow for the possibility of reusing these feature bits later.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>
Add support for performing remote object copies using the 'copy-from'
operation.
[ Add COPY_FROM to get_num_data_items(). ]
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Currently message data items are allocated with ceph_msg_data_create()
in setup_request_data() inside send_request(). send_request() has never
been allowed to fail, so each allocation is followed by a BUG_ON:
data = ceph_msg_data_create(...);
BUG_ON(!data);
It's been this way since support for multiple message data items was
added in commit 6644ed7b7e ("libceph: make message data be a pointer")
in 3.10.
There is no reason to delay the allocation of message data items until
the last possible moment and we certainly don't need a linked list of
them as they are only ever appended to the end and never erased. Make
ceph_msg_new2() take max_data_items and adapt the rest of the code.
Reported-by: Jerry Lee <leisurelysw24@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
struct ceph_pagelist cannot be embedded into anything else because it
has its own refcount. Merge allocation and initialization together.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
If the read is large enough, we end up spinning in the messenger:
libceph: osd0 192.168.122.1:6801 io error
libceph: osd0 192.168.122.1:6801 io error
libceph: osd0 192.168.122.1:6801 io error
This is a receive side limit, so only reads were affected.
Cc: stable@vger.kernel.org
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Derive the signature from the entire buffer (both AES cipher blocks)
instead of using just the first half of the first block, leaving out
data_crc entirely.
This addresses CVE-2018-1129.
Link: http://tracker.ceph.com/issues/24837
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>
When a client authenticates with a service, an authorizer is sent with
a nonce to the service (ceph_x_authorize_[ab]) and the service responds
with a mutation of that nonce (ceph_x_authorize_reply). This lets the
client verify the service is who it says it is but it doesn't protect
against a replay: someone can trivially capture the exchange and reuse
the same authorizer to authenticate themselves.
Allow the service to reject an initial authorizer with a random
challenge (ceph_x_authorize_challenge). The client then has to respond
with an updated authorizer proving they are able to decrypt the
service's challenge and that the new authorizer was produced for this
specific connection instance.
The accepting side requires this challenge and response unconditionally
if the client side advertises they have CEPHX_V2 feature bit.
This addresses CVE-2018-1128.
Link: http://tracker.ceph.com/issues/24836
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>
We already copy authorizer_reply_buf and authorizer_reply_buf_len into
ceph_connection. Factoring out __prepare_write_connect() requires two
more: authorizer_buf and authorizer_buf_len. Store the pointer to the
handshake in con->auth rather than piling on.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>
The request mtime field is used all over ceph, and is currently
represented as a 'timespec' structure in Linux. This changes it to
timespec64 to allow times beyond 2038, modifying all users at the
same time.
[ Remove now redundant ts variable in writepage_nounlock(). ]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
ceph_con_keepalive_expired() is the last user of timespec_add() and some
of the last uses of ktime_get_real_ts(). Replacing this with timespec64
based interfaces lets us remove that deprecated API.
I'm introducing new ceph_encode_timespec64()/ceph_decode_timespec64()
here that take timespec64 structures and convert to/from ceph_timespec,
which is defined to have an unsigned 32-bit tv_sec member. This extends
the range of valid times to year 2106, avoiding the year 2038 overflow.
The ceph file system portion still uses the old functions for inode
timestamps, this will be done separately after the VFS layer is converted.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The wire format dictates that the length of string fits into 4 bytes.
Take u32 instead of size_t to reflect that.
We were already truncating len in ceph_pagelist_encode_32() -- this
just pushes that truncation one level up.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The wire format dictates that payload_len fits into 4 bytes. Take u32
instead of size_t to reflect that.
All callers pass a small integer, so no changes required.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
calc_target() isn't supposed to fail with anything but POOL_DNE, in
which case we report that the pool doesn't exist and fail the request
with -ENOENT. Doing this for -ENOMEM is at the very least confusing
and also harmful -- as the preceding requests complete, a short-lived
locator string allocation is likely to succeed after a wait.
(We used to call ceph_object_locator_to_pg() for a pi lookup. In
theory that could fail with -ENOENT, hence the "ret != -ENOENT" warning
being removed.)
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The intent behind making it a per-request setting was that it would be
set for writes, but not for reads. As it is, the flag is set for all
fs/ceph requests except for pool perm check stat request (technically
a read).
ceph_osdc_abort_on_full() skips reads since the previous commit and
I don't see a use case for marking individual requests.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
In the common case, req->r_callback is called by handle_reply() on the
ceph-msgr worker thread without any locks. If handle_reply() fails, it
is called with both osd->lock and osdc->lock. In the map check case,
it is called with just osdc->lock but held for write. Finally, if the
request is aborted because of -ENOSPC or by ceph_osdc_abort_requests(),
it is called directly on the submitter's thread, again with both locks.
req->r_callback on the submitter's thread is relatively new (introduced
in 4.12) and ripe for deadlocks -- e.g. writeback worker thread waiting
on itself:
inode_wait_for_writeback+0x26/0x40
evict+0xb5/0x1a0
iput+0x1d2/0x220
ceph_put_wrbuffer_cap_refs+0xe0/0x2c0 [ceph]
writepages_finish+0x2d3/0x410 [ceph]
__complete_request+0x26/0x60 [libceph]
complete_request+0x2e/0x70 [libceph]
__submit_request+0x256/0x330 [libceph]
submit_request+0x2b/0x30 [libceph]
ceph_osdc_start_request+0x25/0x40 [libceph]
ceph_writepages_start+0xdfe/0x1320 [ceph]
do_writepages+0x1f/0x70
__writeback_single_inode+0x45/0x330
writeback_sb_inodes+0x26a/0x600
__writeback_inodes_wb+0x92/0xc0
wb_writeback+0x274/0x330
wb_workfn+0x2d5/0x3b0
Defer __complete_request() to a workqueue in all failure cases so it's
never on the same thread as ceph_osdc_start_request() and always called
with no locks held.
Link: http://tracker.ceph.com/issues/23978
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
rstat is not tracked by capability. client can't know if rstat from
non-auth mds is uptodate or not.
Link: http://tracker.ceph.com/issues/23538
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
... and store num_bvecs for client code's convenience.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
This patch adds the infrastructure required to support cephfs quotas as it
is currently implemented in the ceph fuse client. Cephfs quotas can be
set on any directory, and can restrict the number of bytes or the number
of files stored beneath that point in the directory hierarchy.
Quotas are set using the extended attributes 'ceph.quota.max_files' and
'ceph.quota.max_bytes', and can be removed by setting these attributes to
'0'.
Link: http://tracker.ceph.com/issues/22372
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
In current code, regular file and directory use same struct
ceph_file_info to store fs specific data so the struct has to
include some fields which are only used for directory
(e.g., readdir related info), when having plenty of regular files,
it will lead to memory waste.
This patch introduces dedicated ceph_dir_file_info cache for
readdir related thins. So that regular file does not include those
unused fields anymore.
Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
In preparation for rbd "fancy" striping, introduce ceph_bvec_iter for
working with bio_vec array data buffers. The wrappers are trivial, but
make it look similar to ceph_bio_iter.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The reason we clone bios is to be able to give each object request
(and consequently each ceph_osd_data/ceph_msg_data item) its own
pointer to a (list of) bio(s). The messenger then initializes its
cursor with cloned bio's ->bi_iter, so it knows where to start reading
from/writing to. That's all the cloned bios are used for: to determine
each object request's starting position in the provided data buffer.
Introduce ceph_bio_iter to do exactly that -- store position within bio
list (i.e. pointer to bio) + position within that bio (i.e. bvec_iter).
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
- make it void
- xlen (object extent length) out parameter should be u32 because only
a single stripe unit is mapped at a time
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Improve accuracy of statfs reporting for Ceph filesystems comprising
exactly one data pool. In this case, the Ceph monitor can now report
the space usage for the single data pool instead of the global data
for the entire Ceph cluster. Include support for this message in
mon_client and leverage it in ceph/super.
Signed-off-by: Douglas Fuller <dfuller@redhat.com>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
These flags tell mds if there is pending capsnap explicitly.
Without this explicit notification, mds can only conclude if
client has pending capsnap. The method mds use is inefficient
and error-prone.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
startsync is a no-op, has been for years. Remove it.
Link: http://tracker.ceph.com/issues/20604
Signed-off-by: Yanhu Cao <gmayyyha@gmail.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
This is needed so that the OSDs can regenerate the missing set at the
start of a new interval where support for recovery deletes changed.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>
The new macros don't follow the usual style for declarations,
which we get a warning for with 'make W=1':
In file included from fs/ceph/mds_client.c:16:0:
include/linux/ceph/ceph_features.h:74:1: error: 'static' is not at beginning of declaration [-Werror=old-style-declaration]
This moves the 'static' keyword to the front of the
declaration.
Fixes: f179d3ba8c ("libceph: new features macros")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
All four SERVER_LUMINOUS feature bits are implemented, switch it on!
NEW_OSDOP_ENCODING doesn't mean much for the client (it signifies
support for MOSDOp v6) but needs to be enabled in order to get the
latest (currently v25) pg_pool_t.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Sage Weil <sage@redhat.com>
pg_temp and pg_upmap encodings are the same (PG -> array of osds),
except for the incremental remove: it's an empty mapping in new_pg_temp
for pg_temp and a separate old_pg_upmap set for pg_upmap. (This isn't
to allow for empty pg_upmap mappings -- apparently, pg_temp just wasn't
looked at as an example for pg_upmap encoding.)
Reuse __decode_pg_temp() for decoding pg_upmap and new_pg_upmap.
__decode_pg_temp() stores into pg_temp union member, but since pg_upmap
union member is identical, reading through pg_upmap later is OK.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Some of these won't be as efficient as they could be (e.g.
ceph_decode_skip_set(... 32 ...) could advance by len * sizeof(u32)
once instead of advancing by sizeof(u32) len times), but that's fine
and not worth a bunch of extra macro code.
Replace skip_name_map() with ceph_decode_skip_map as an example.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Initially for ceph_pg_mapping, ceph_spg_mapping and ceph_hobject_id,
compared with ceph_pg_compare(), ceph_spg_compare() and hoid_compare()
respectively.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Otherwise we may miss events like PG splits, pool deletions, etc when
we get multiple incremental maps at once. Because check_pool_dne() can
now be fed an unlinked request, finish_request() needed to be taught to
handle unlinked requests.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
