libceph: optionally use bounce buffer on recv path in crc mode

Both msgr1 and msgr2 in crc mode are zero copy in the sense that
message data is read from the socket directly into the destination
buffer. We assume that the destination buffer is stable (i.e. remains
unchanged while it is being read to) though. Otherwise, CRC errors
ensue:

libceph: read_partial_message 0000000048edf8ad data crc 1063286393 != exp. 228122706
libceph: osd1 (1)192.168.122.1:6843 bad crc/signature

libceph: bad data crc, calculated 57958023, expected 1805382778
libceph: osd2 (2)192.168.122.1:6876 integrity error, bad crc

Introduce rxbounce option to enable use of a bounce buffer when
receiving message data. In particular this is needed if a mapped
image is a Windows VM disk, passed to QEMU. Windows has a system-wide
"dummy" page that may be mapped into the destination buffer (potentially
more than once into the same buffer) by the Windows Memory Manager in
an effort to generate a single large I/O [1][2]. QEMU makes a point of
preserving overlap relationships when cloning I/O vectors, so krbd gets
exposed to this behaviour.

[1] "What Is Really in That MDL?"
https://docs.microsoft.com/en-us/previous-versions/windows/hardware/design/dn614012(v=vs.85)
[2] https://blogs.msmvps.com/kernelmustard/2005/05/04/dummy-pages/

URL: https://bugzilla.redhat.com/show_bug.cgi?id=1973317
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

libceph: rename parse_fsid() to ceph_parse_fsid() and export

... as it is too generic. also, use __func__ when logging
rather than hardcoding the function name.

Signed-off-by: Venky Shankar <vshankar@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

libceph: generalize addr/ip parsing based on delimiter

... and remove hardcoded function name in ceph_parse_ips().

[ idryomov: delim parameter, drop CEPH_ADDR_PARSE_DEFAULT_DELIM ]

Signed-off-by: Venky Shankar <vshankar@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

mm: allow !GFP_KERNEL allocations for kvmalloc

Support for GFP_NO{FS,IO} and __GFP_NOFAIL has been implemented by
previous patches so we can allow the support for kvmalloc. This will
allow some external users to simplify or completely remove their
helpers.

GFP_NOWAIT semantic hasn't been supported so far but it hasn't been
explicitly documented so let's add a note about that.

ceph_kvmalloc is the first helper to be dropped and changed to kvmalloc.

Link: https://lkml.kernel.org/r/20211122153233.9924-5-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

libceph: remove osdtimeout option entirely

Commit 83aff95eb9d6 ("libceph: remove 'osdtimeout' option") deprecated
osdtimeout over 8 years ago, but it is still recognized. Let's remove
it entirely.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

libceph: deprecate [no]cephx_require_signatures options

These options were introduced in 3.19 with support for message signing
and are rather useless, as explained in commit a51983e4dd2d ("libceph:
add nocephx_sign_messages option"). Deprecate them.

In case there is someone out there with a cluster that lacks support
for MSG_AUTH feature (very unlikely but has to be considered since we
haven't formally raised the bar from argonaut to bobtail yet), make
nocephx_sign_messages also waive MSG_AUTH requirement. This is probably
how it should have been done in the first place -- if we aren't going
to sign, requiring the signing feature makes no sense.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

libceph: introduce connection modes and ms_mode option

msgr2 supports two connection modes: crc (plain) and secure (on-wire
encryption). Connection mode is picked by server based on input from
client.

Introduce ms_mode option:

ms_mode=legacy - msgr1 (default)
ms_mode=crc - crc mode, if denied fail
ms_mode=secure - secure mode, if denied fail
ms_mode=prefer-crc - crc mode, if denied agree to secure mode
ms_mode=prefer-secure - secure mode, if denied agree to crc mode

ms_mode affects all connections, we don't separate connections to mons
like it's done in userspace with ms_client_mode vs ms_mon_client_mode.

For now the default is legacy, to be flipped to prefer-crc after some
time.

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

libceph: move away from global osd_req_flags

osd_req_flags is overly general and doesn't suit its only user
(read_from_replica option) well:

- applying osd_req_flags in account_request() affects all OSD
requests, including linger (i.e. watch and notify). However,
linger requests should always go to the primary even though
some of them are reads (e.g. notify has side effects but it
is a read because it doesn't result in mutation on the OSDs).

- calls to class methods that are reads are allowed to go to
the replica, but most such calls issued for "rbd map" and/or
exclusive lock transitions are requested to be resent to the
primary via EAGAIN, doubling the latency.

Get rid of global osd_req_flags and set read_from_replica flag
only on specific OSD requests instead.

Fixes: 8ad44d5e0d1e ("libceph: read_from_replica option")
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

mm: remove map_vm_range

Switch all callers to map_kernel_range, which symmetric to the unmap side
(as well as the _noflush versions).

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Gao Xiang <xiang@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Kelley <mikelley@microsoft.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Wei Liu <wei.liu@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200414131348.444715-17-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

libceph: read_from_replica option

Expose replica reads through read_from_replica=balance and
read_from_replica=localize. The default is to read from primary
(read_from_replica=no).

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

libceph: crush_location infrastructure

Allow expressing client's location in terms of CRUSH hierarchy as
a set of (bucket type name, bucket name) pairs. The userspace syntax
"crush_location = key1=value1 key2=value2" is incompatible with mount
options and needed adaptation. Key-value pairs are separated by '|'
and we use ':' instead of '=' to separate keys from values. So for:

crush_location = host=foo rack=bar

one would write:

crush_location=host:foo|rack:bar

As in userspace, "multipath" locations are supported, so indicating
locality for parallel hierarchies is possible:

crush_location=rack:foo1|rack:foo2|datacenter:bar

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

fs_parse: fold fs_parameter_desc/fs_parameter_spec

The former contains nothing but a pointer to an array of the latter...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs_parser: remove fs_parameter_description name field

Unused now.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

ceph_parse_param(), ceph_parse_mon_ips(): switch to passing fc_log

... and now errorf() et.al. are never called with NULL fs_context,
so we can get rid of conditional in those.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

new primitive: __fs_parse()

fs_parse() analogue taking p_log instead of fs_context.
fs_parse() turned into a wrapper, callers in ceph_common and rbd
switched to __fs_parse().

As the result, fs_parse() never gets NULL fs_context and neither
do fs_context-based logging primitives

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

switch rbd and libceph to p_log-based primitives

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs_parse: get rid of ->enums

Don't do a single array; attach them to fsparam_enum() entry
instead. And don't bother trying to embed the names into those -
it actually loses memory, with no real speedup worth mentioning.

Simplifies validation as well.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

libceph, rbd, ceph: convert to use the new mount API

Convert the ceph filesystem to the new internal mount API as the old
one will be obsoleted and removed. This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.

See Documentation/filesystems/mount_api.txt for more information.

[ Numerous string handling, leak and regression fixes; rbd conversion
was particularly broken and had to be redone almost from scratch. ]

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

libceph: avoid a __vmalloc() deadlock in ceph_kvmalloc()

The vmalloc allocator doesn't fully respect the specified gfp mask:
while the actual pages are allocated as requested, the page table pages
are always allocated with GFP_KERNEL. ceph_kvmalloc() may be called
with GFP_NOFS and GFP_NOIO (for ceph and rbd respectively), so this may
result in a deadlock.

There is no real reason for the current PAGE_ALLOC_COSTLY_ORDER logic,
it's just something that seemed sensible at the time (ceph_kvmalloc()
predates kvmalloc()). kvmalloc() is smarter: in an attempt to reduce
long term fragmentation, it first tries to kmalloc non-disruptively.

Switch to kvmalloc() and set the respective PF_MEMALLOC_* flag using
the scope API to avoid the deadlock. Note that kvmalloc() needs to be
passed GFP_KERNEL to enable the fallback.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

libceph: add function that reset client's entity addr

This function also re-open connections to OSD/MON, and re-send in-flight
OSD requests after re-opening connections to OSD.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Revert "Merge tag 'keys-acl-20190703' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs"

This reverts merge 0f75ef6a9cff49ff612f7ce0578bced9d0b38325 (and thus
effectively commits

7a1ade847596 ("keys: Provide KEYCTL_GRANT_PERMISSION")
2e12256b9a76 ("keys: Replace uid/gid/perm permissions checking with an ACL")

that the merge brought in).

It turns out that it breaks booting with an encrypted volume, and Eric
biggers reports that it also breaks the fscrypt tests [1] and loading of
in-kernel X.509 certificates [2].

The root cause of all the breakage is likely the same, but David Howells
is off email so rather than try to work it out it's getting reverted in
order to not impact the rest of the merge window.

[1] https://lore.kernel.org/lkml/20190710011559.GA7973@sol.localdomain/
[2] https://lore.kernel.org/lkml/20190710013225.GB7973@sol.localdomain/

Link: https://lore.kernel.org/lkml/CAHk-=wjxoeMJfeBahnWH=9zShKp2bsVy527vo3_y8HfOdhwAAw@mail.gmail.com/
Reported-by: Eric Biggers <ebiggers@kernel.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ceph: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.

This cleanup allows the return value of the functions to be made void,
as no logic should care if these files succeed or not.

Cc: "Yan, Zheng" <zyan@redhat.com>
Cc: Sage Weil <sage@redhat.com>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: ceph-devel@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190612145538.GA18772@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

keys: Replace uid/gid/perm permissions checking with an ACL

Replace the uid/gid/perm permissions checking on a key with an ACL to allow
the SETATTR and SEARCH permissions to be split. This will also allow a
greater range of subjects to represented.

============
WHY DO THIS?
============

The problem is that SETATTR and SEARCH cover a slew of actions, not all of
which should be grouped together.

For SETATTR, this includes actions that are about controlling access to a
key:

(1) Changing a key's ownership.

(2) Changing a key's security information.

(3) Setting a keyring's restriction.

And actions that are about managing a key's lifetime:

(4) Setting an expiry time.

(5) Revoking a key.

and (proposed) managing a key as part of a cache:

(6) Invalidating a key.

Managing a key's lifetime doesn't really have anything to do with
controlling access to that key.

Expiry time is awkward since it's more about the lifetime of the content
and so, in some ways goes better with WRITE permission. It can, however,
be set unconditionally by a process with an appropriate authorisation token
for instantiating a key, and can also be set by the key type driver when a
key is instantiated, so lumping it with the access-controlling actions is
probably okay.

As for SEARCH permission, that currently covers:

(1) Finding keys in a keyring tree during a search.

(2) Permitting keyrings to be joined.

(3) Invalidation.

But these don't really belong together either, since these actions really
need to be controlled separately.

Finally, there are number of special cases to do with granting the
administrator special rights to invalidate or clear keys that I would like
to handle with the ACL rather than key flags and special checks.


===============
WHAT IS CHANGED
===============

The SETATTR permission is split to create two new permissions:

(1) SET_SECURITY - which allows the key's owner, group and ACL to be
changed and a restriction to be placed on a keyring.

(2) REVOKE - which allows a key to be revoked.

The SEARCH permission is split to create:

(1) SEARCH - which allows a keyring to be search and a key to be found.

(2) JOIN - which allows a keyring to be joined as a session keyring.

(3) INVAL - which allows a key to be invalidated.

The WRITE permission is also split to create:

(1) WRITE - which allows a key's content to be altered and links to be
added, removed and replaced in a keyring.

(2) CLEAR - which allows a keyring to be cleared completely. This is
split out to make it possible to give just this to an administrator.

(3) REVOKE - see above.


Keys acquire ACLs which consist of a series of ACEs, and all that apply are
unioned together. An ACE specifies a subject, such as:

(*) Possessor - permitted to anyone who 'possesses' a key
(*) Owner - permitted to the key owner
(*) Group - permitted to the key group
(*) Everyone - permitted to everyone

Note that 'Other' has been replaced with 'Everyone' on the assumption that
you wouldn't grant a permit to 'Other' that you wouldn't also grant to
everyone else.

Further subjects may be made available by later patches.

The ACE also specifies a permissions mask. The set of permissions is now:

VIEW Can view the key metadata
READ Can read the key content
WRITE Can update/modify the key content
SEARCH Can find the key by searching/requesting
LINK Can make a link to the key
SET_SECURITY Can change owner, ACL, expiry
INVAL Can invalidate
REVOKE Can revoke
JOIN Can join this keyring
CLEAR Can clear this keyring


The KEYCTL_SETPERM function is then deprecated.

The KEYCTL_SET_TIMEOUT function then is permitted if SET_SECURITY is set,
or if the caller has a valid instantiation auth token.

The KEYCTL_INVALIDATE function then requires INVAL.

The KEYCTL_REVOKE function then requires REVOKE.

The KEYCTL_JOIN_SESSION_KEYRING function then requires JOIN to join an
existing keyring.

The JOIN permission is enabled by default for session keyrings and manually
created keyrings only.


======================
BACKWARD COMPATIBILITY
======================

To maintain backward compatibility, KEYCTL_SETPERM will translate the
permissions mask it is given into a new ACL for a key - unless
KEYCTL_SET_ACL has been called on that key, in which case an error will be
returned.

It will convert possessor, owner, group and other permissions into separate
ACEs, if each portion of the mask is non-zero.

SETATTR permission turns on all of INVAL, REVOKE and SET_SECURITY. WRITE
permission turns on WRITE, REVOKE and, if a keyring, CLEAR. JOIN is turned
on if a keyring is being altered.

The KEYCTL_DESCRIBE function translates the ACL back into a permissions
mask to return depending on possessor, owner, group and everyone ACEs.

It will make the following mappings:

(1) INVAL, JOIN -> SEARCH

(2) SET_SECURITY -> SETATTR

(3) REVOKE -> WRITE if SETATTR isn't already set

(4) CLEAR -> WRITE

Note that the value subsequently returned by KEYCTL_DESCRIBE may not match
the value set with KEYCTL_SETATTR.


=======
TESTING
=======

This passes the keyutils testsuite for all but a couple of tests:

(1) tests/keyctl/dh_compute/badargs: The first wrong-key-type test now
returns EOPNOTSUPP rather than ENOKEY as READ permission isn't removed
if the type doesn't have ->read(). You still can't actually read the
key.

(2) tests/keyctl/permitting/valid: The view-other-permissions test doesn't
work as Other has been replaced with Everyone in the ACL.

Signed-off-by: David Howells <dhowells@redhat.com>

treewide: Add SPDX license identifier for more missed files

Add SPDX license identifiers to all files which:

- Have no license information of any form

- Have MODULE_LICENCE("GPL*") inside which was used in the initial
scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

libceph: wait for latest osdmap in ceph_monc_blacklist_add()

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: 6305a3b41515 ("libceph: support for blacklisting clients")
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jason Dillaman <dillaman@redhat.com>

libceph: allow setting abort_on_full for rbd

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>

libceph: remove unnecessary non NULL check for request_key

request_key never return NULL,so no need do non-NULL check.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

libceph: amend "bad option arg" error message

Don't mention "mount" -- in the rbd case it is "mapping".

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

libceph: stop parsing when a bad int arg is detected

There is no reason to continue option parsing after detecting
bad option.

[ Return match_int() errors from ceph_parse_options() to match the
behaviour of parse_rbd_opts_token() and parse_fsopt_token(). ]

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

ceph: quota: add initial infrastructure to support cephfs quotas

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>

libceph: adding missing message types to ceph_msg_type_name()

Some of message types are missing in ceph_msg_type_name(),
so just adding them for better understanding of output information.

Signed-off-by: Chengguang Xu <cgxu519@icloud.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

ceph: add newline to end of debug message format

Some of dout format do not include newline in the end,
fix for the files which are in fs/ceph and net/ceph directories,
and changing printk to dout for printing debug info in super.c

Signed-off-by: Chengguang Xu <cgxu519@icloud.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

net: Use octal not symbolic permissions

Prefer the direct use of octal for permissions.

Done with checkpatch -f --types=SYMBOLIC_PERMS --fix-inplace
and some typing.

Miscellanea:

o Whitespace neatening around these conversions.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

libceph, ceph: avoid memory leak when specifying same option several times

When parsing string option, in order to avoid memory leak we need to
carefully free it first in case of specifying same option several times.

Signed-off-by: Chengguang Xu <cgxu519@icloud.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

libceph: check kstrndup() return value

Should check result of kstrndup() in case of memory allocation failure.

Signed-off-by: Chengguang Xu <cgxu519@icloud.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

libceph: respect RADOS_BACKOFF backoffs

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

ceph: ensure RNG is seeded before using

Ceph uses the RNG for various nonce generations, and it shouldn't accept
using bad randomness. So, we wait for the RNG to be properly seeded. We
do this by calling wait_for_random_bytes() in a function that is
certainly called in process context, early on, so that all subsequent
calls to get_random_bytes are necessarily acceptable.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: "Yan, Zheng" <zyan@redhat.com>
Cc: Sage Weil <sage@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

libceph: use kbasename() and kill ceph_file_part()

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

mm, vmalloc: use __GFP_HIGHMEM implicitly

__vmalloc* allows users to provide gfp flags for the underlying
allocation. This API is quite popular

$ git grep "=[[:space:]]__vmalloc\|return[[:space:]]*__vmalloc" | wc -l
77

The only problem is that many people are not aware that they really want
to give __GFP_HIGHMEM along with other flags because there is really no
reason to consume precious lowmemory on CONFIG_HIGHMEM systems for pages
which are mapped to the kernel vmalloc space. About half of users don't
use this flag, though. This signals that we make the API unnecessarily
too complex.

This patch simply uses __GFP_HIGHMEM implicitly when allocating pages to
be mapped to the vmalloc space. Current users which add __GFP_HIGHMEM
are simplified and drop the flag.

Link: http://lkml.kernel.org/r/20170307141020.29107-1-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Cristopher Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

libceph: supported_features module parameter

Add a readonly, exported to sysfs module parameter so that userspace
can generate meaningful error messages. It's a bit funky, but there is
no other libceph-specific place.

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

libceph, ceph: always advertise all supported features

No reason to hide CephFS-specific features in the rbd case. Recent
feature bits mix RADOS and CephFS-specific stuff together anyway.

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

libceph: osd_request_timeout option

osd_request_timeout specifies how many seconds to wait for a response
from OSDs before returning -ETIMEDOUT from an OSD request. 0 (default)
means no limit.

osd_request_timeout is osdkeepalive-precise -- in-flight requests are
swept through every osdkeepalive seconds. With ack vs commit behaviour
gone, abort_request() is really simple.

This is based on a patch from Artur Molchanov <artur.molchanov@synesis.ru>.

Tested-by: Artur Molchanov <artur.molchanov@synesis.ru>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>

rbd: add 'client_addr' sysfs rbd device attribute

Export client addr/nonce, so userspace can check if a image is being
blacklisted.

Signed-off-by: Mike Christie <mchristi@redhat.com>
[idryomov@gmail.com: ceph_client_addr(), endianess fix]
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

libceph: rename ceph_client_id() -> ceph_client_gid()

It's gid / global_id in other places.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Alex Elder <elder@linaro.org>

libceph: introduce reference counted string

The data structure is for storing namesapce string. It allows namespace
string to be shared between cephfs inodes with same layout. This data
structure can also be referenced by OSD request.

Signed-off-by: Yan, Zheng <zyan@redhat.com>

ceph: make logical calculation functions return bool

This patch makes serverl logical caculation functions return bool to
improve readability due to these particular functions only using 0/1
as their return value.

No functional change.

Signed-off-by: Zhang Zhuoyu <zhangzhuoyu@cmss.chinamobile.com>

libceph: monc ping rate is 10s

Split ping interval and ping timeout: ping interval is 10s; keepalive
timeout is 30s.

Make monc_ping_timeout a constant while at it - it's not actually
exported as a mount option (and the rest of tick-related settings won't
be either), so it's got no place in ceph_options.

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

libceph: move debugfs initialization into __ceph_open_session()

Our debugfs dir name is a concatenation of cluster fsid and client
unique ID ("global_id"). It used to be the case that we learned
global_id first, nowadays we always learn fsid first - the monmap is
sent before any auth replies are. ceph_debugfs_client_init() call in
ceph_monc_handle_map() is therefore never executed and can be removed.

Its counterpart in handle_auth_reply() doesn't really belong there
either: having to do monc->client and unlocking early to work around
lockdep is a testament to that. Move it into __ceph_open_session(),
where it can be called unconditionally.

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

libceph: add nocephx_sign_messages option

Support for message signing was merged into 3.19, along with
nocephx_require_signatures option. But, all that option does is allow
the kernel client to talk to clusters that don't support MSG_AUTH
feature bit. That's pretty useless, given that it's been supported
since bobtail.

Meanwhile, if one disables message signing on the server side with
"cephx sign messages = false", it becomes impossible to use the kernel
client since it expects messages to be signed if MSG_AUTH was
negotiated. Add nocephx_sign_messages option to support this use case.

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

libceph: stop duplicating client fields in messenger

supported_features and required_features serve no purpose at all, while
nocrc and tcp_nodelay belong to ceph_options::flags.

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

KEYS: Merge the type-specific data with the payload data

Merge the type-specific data with the payload data into one four-word chunk
as it seems pointless to keep them separate.

Use user_key_payload() for accessing the payloads of overloaded
user-defined keys.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-cifs@vger.kernel.org
cc: ecryptfs@vger.kernel.org
cc: linux-ext4@vger.kernel.org
cc: linux-f2fs-devel@lists.sourceforge.net
cc: linux-nfs@vger.kernel.org
cc: ceph-devel@vger.kernel.org
cc: linux-ima-devel@lists.sourceforge.net

libceph: use keepalive2 to verify the mon session is alive

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

fs: create and use seq_show_option for escaping

Many file systems that implement the show_options hook fail to correctly
escape their output which could lead to unescaped characters (e.g. new
lines) leaking into /proc/mounts and /proc/[pid]/mountinfo files. This
could lead to confusion, spoofed entries (resulting in things like
systemd issuing false d-bus "mount" notifications), and who knows what
else. This looks like it would only be the root user stepping on
themselves, but it's possible weird things could happen in containers or
in other situations with delegated mount privileges.

Here's an example using overlay with setuid fusermount trusting the
contents of /proc/mounts (via the /etc/mtab symlink). Imagine the use
of "sudo" is something more sneaky:

$ BASE="ovl"
$ MNT="$BASE/mnt"
$ LOW="$BASE/lower"
$ UP="$BASE/upper"
$ WORK="$BASE/work/ 0 0
none /proc fuse.pwn user_id=1000"
$ mkdir -p "$LOW" "$UP" "$WORK"
$ sudo mount -t overlay -o "lowerdir=$LOW,upperdir=$UP,workdir=$WORK" none /mnt
$ cat /proc/mounts
none /root/ovl/mnt overlay rw,relatime,lowerdir=ovl/lower,upperdir=ovl/upper,workdir=ovl/work/ 0 0
none /proc fuse.pwn user_id=1000 0 0
$ fusermount -u /proc
$ cat /proc/mounts
cat: /proc/mounts: No such file or directory

This fixes the problem by adding new seq_show_option and
seq_show_option_n helpers, and updating the vulnerable show_option
handlers to use them as needed. Some, like SELinux, need to be open
coded due to unusual existing escape mechanisms.

[akpm@linux-foundation.org: add lost chunk, per Kees]
[keescook@chromium.org: seq_show_option should be using const parameters]
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Acked-by: Jan Kara <jack@suse.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Cc: J. R. Okajima <hooanon05g@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

libceph: enable ceph in a non-default network namespace

Grab a reference on a network namespace of the 'rbd map' (in case of
rbd) or 'mount' (in case of ceph) process and use that to open sockets
instead of always using init_net and bailing if network namespace is
anything but init_net. Be careful to not share struct ceph_client
instances between different namespaces and don't add any code in the
!CONFIG_NET_NS case.

This is based on a patch from Hong Zhiguo <zhiguohong@tencent.com>.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>

libceph: fix wrong name "Ceph filesystem for Linux"

modinfo libceph prints the module name "Ceph filesystem for Linux",
which is same as the real fs module ceph. It's confusing.

Signed-off-by: Hong Zhiguo <zhiguohong@tencent.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

libceph: a couple tweaks for wait loops

- return -ETIMEDOUT instead of -EIO in case of timeout
- wait_event_interruptible_timeout() returns time left until timeout
and since it can be almost LONG_MAX we had better assign it to long

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

libceph: store timeouts in jiffies, verify user input

There are currently three libceph-level timeouts that the user can
specify on mount: mount_timeout, osd_idle_ttl and osdkeepalive. All of
these are in seconds and no checking is done on user input: negative
values are accepted, we multiply them all by HZ which may or may not
overflow, arbitrarily large jiffies then get added together, etc.

There is also a bug in the way mount_timeout=0 is handled. It's
supposed to mean "infinite timeout", but that's not how wait.h APIs
treat it and so __ceph_open_session() for example will busy loop
without much chance of being interrupted if none of ceph-mons are
there.

Fix all this by verifying user input, storing timeouts capped by
msecs_to_jiffies() in jiffies and using the new ceph_timeout_jiffies()
helper for all user-specified waits to handle infinite timeouts
correctly.

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

libceph, ceph: split ceph_show_options()

Split ceph_show_options() into two pieces and move the piece
responsible for printing client (libceph) options into net/ceph. This
way people adding a libceph option wouldn't have to remember to update
code in fs/ceph.

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

libceph: tcp_nodelay support

TCP_NODELAY socket option set on connection sockets,
disables Nagle’s algorithm and improves latency characteristics.
tcp_nodelay(default)/notcp_nodelay option flags provided to
enable/disable setting the socket option.

Signed-off-by: Chaitanya Huilgol <chaitanya.huilgol@sandisk.com>
[idryomov@redhat.com: NO_TCP_NODELAY -> TCP_NODELAY, minor adjustments]
Signed-off-by: Ilya Dryomov <idryomov@redhat.com>

libceph: require cephx message signature by default

Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@redhat.com>

libceph: nuke ceph_kvfree()

Use kvfree() from linux/mm.h instead, which is identical. Also fix the
ceph_buffer comment: we will allocate with kmalloc() up to 32k - the
value of PAGE_ALLOC_COSTLY_ORDER, but that really is just an
implementation detail so don't mention it at all.

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

libceph: Convert pr_warning to pr_warn

Use the more common pr_warn.

Other miscellanea:

o Coalesce formats
o Realign arguments

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>

libceph: mon_get_version request infrastructure

Add support for mon_get_version requests to libceph. This reuses much
of the ceph_mon_generic_request infrastructure, with one exception.
Older OSDs don't set mon_get_version reply hdr->tid even if the
original request had a non-zero tid, which makes it impossible to
lookup ceph_mon_generic_request contexts by tid in get_generic_reply()
for such replies. As a workaround, we allocate a reply message on the
reply path. This can probably interfere with revoke, but I don't see
a better way.

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>

libceph: add ceph_kv{malloc,free}() and switch to them

Encapsulate kmalloc vs vmalloc memory allocation and freeing logic into
two helpers, ceph_kvmalloc() and ceph_kvfree(), and switch to them.

ceph_kvmalloc() kmalloc()'s a maximum of 8 pages, anything bigger is
vmalloc()'ed with __GFP_HIGHMEM set. This changes the existing
behaviour:

- for buffers (ceph_buffer_new()), from trying to kmalloc() everything
and using vmalloc() just as a fallback

- for messages (ceph_msg_new()), from going to vmalloc() for anything
bigger than a page

- for messages (ceph_msg_new()), from disallowing vmalloc() to use high
memory

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>

libceph: all features fields must be u64

In preparation for ceph_features.h update, change all features fields
from unsigned int/u32 to u64. (ceph.git has ~40 feature bits at this
point.)

Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>

libceph: use slab cache for osd client requests

Create a slab cache to manage allocation of ceph_osdc_request
structures.

This resolves:
http://tracker.ceph.com/issues/3926

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

ceph: update support for PGID64, PGPOOL3, OSDENC protocol features

Support (and require) the PGID64, PGPOOL3, and OSDENC protocol features.
These have been present in ceph.git since v0.42, Feb 2012. Require these
features to simplify support; nobody is running older userspace.

Note that the new request and reply encoding is still not in place, so the new
code is not yet functional.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>

rbd: don't take extra bio reference for osd client

Currently, if the OSD client finds an osd request has had a bio list
attached to it, it drops a reference to it (or rather, to the first
entry on that list) when the request is released.

The code that added that reference (i.e., the rbd client) is
therefore required to take an extra reference to that first bio
structure.

The osd client doesn't really do anything with the bio pointer other
than transfer it from the osd request structure to outgoing (for
writes) and ingoing (for reads) messages. So it really isn't the
right place to be taking or dropping references.

Furthermore, the rbd client already holds references to all bio
structures it passes to the osd client, and holds them until the
request is completed. So there's no need for this extra reference
whatsoever.

So remove the bio_put() call in ceph_osdc_release_request(), as
well as its matching bio_get() call in rbd_osd_req_create().

This change could lead to a crash if old libceph.ko was used with
new rbd.ko. Add a compatibility check at rbd initialization time to
avoid this possibilty.

This resolves:
http://tracker.ceph.com/issues/3798 and
http://tracker.ceph.com/issues/3799

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

libceph: add a compatibility check interface

An upcoming change implements semantic change that could lead to
a crash if an old version of the libceph kernel module is used with
a new version of the rbd kernel module.

In order to preclude that possibility, this adds a compatibilty
check interface. If this interface doesn't exist, the modules are
obviously not compatible. But if it does exist, this provides a way
of letting the caller know whether it will operate properly with
this libceph module.

Perhaps confusingly, it returns false right now. The semantic
change mentioned above will make it return true.

This resolves:
http://tracker.ceph.com/issues/3800

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>

ceph: Only allow mounts in the initial network namespace

Today ceph opens tcp sockets from a delayed work callback. Delayed
work happens from kernel threads which are always in the initial
network namespace. Therefore fail early if someone attempts
to mount a ceph filesystem from something other than the initial
network namespace.

Cc: Sage Weil <sage@inktank.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

libceph: remove 'osdtimeout' option

This would reset a connection with any OSD that had an outstanding
request that was taking more than N seconds. The idea was that if the
OSD was buggy, the client could compensate by resending the request.

In reality, this only served to hide server bugs, and we haven't
actually seen such a bug in quite a while. Moreover, the userspace
client code never did this.

More importantly, often the request is taking a long time because the
OSD is trying to recover, or overloaded, and killing the connection
and retrying would only make the situation worse by giving the OSD
more work to do.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>

libceph: delay debugfs initialization until we learn global_id

The debugfs directory includes the cluster fsid and our unique global_id.
We need to delay the initialization of the debug entry until we have
learned both the fsid and our global_id from the monitor or else the
second client can't create its debugfs entry and will fail (and multiple
client instances aren't properly reflected in debugfs).

Reported by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>

libceph: move feature bits to separate header

This is simply cleanup that will keep things more closely synced with the
userland code.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>

libceph: prevent the race of incoming work during teardown

Add an atomic variable 'stopping' as flag in struct ceph_messenger,
set this flag to 1 in function ceph_destroy_client(), and add the condition code
in function ceph_data_ready() to test the flag value, if true(1), just return.

Signed-off-by: Guanjun He <gjhe@suse.com>
Reviewed-by: Sage Weil <sage@inktank.com>

libceph: flush msgr queue during mon_client shutdown

We need to flush the msgr workqueue during mon_client shutdown to
ensure that any work affecting our embedded ceph_connection is
finished so that we can be safely destroyed.

Previously, we were flushing the work queue after osd_client
shutdown and before mon_client shutdown to ensure that any osd
connection refs to authorizers are flushed. Remove the redundant
flush, and document in the comment that the mon_client flush is
needed to cover that case as well.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
(cherry picked from commit f3dea7edd3d449fe7a6d402c1ce56a294b985261)

libceph: flush msgr queue during mon_client shutdown

We need to flush the msgr workqueue during mon_client shutdown to
ensure that any work affecting our embedded ceph_connection is
finished so that we can be safely destroyed.

Previously, we were flushing the work queue after osd_client
shutdown and before mon_client shutdown to ensure that any osd
connection refs to authorizers are flushed. Remove the redundant
flush, and document in the comment that the mon_client flush is
needed to cover that case as well.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>

libceph: embed ceph messenger structure in ceph_client

A ceph client has a pointer to a ceph messenger structure in it.
There is always exactly one ceph messenger for a ceph client, so
there is no need to allocate it separate from the ceph client
structure.

Switch the ceph_client structure to embed its ceph_messenger
structure.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Yehuda Sadeh <yehuda@inktank.com>
Reviewed-by: Sage Weil <sage@inktank.com>

net: cleanup unsigned to unsigned int

Use of "unsigned int" is preferred to bare "unsigned" in net tree.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ceph: ensure Boolean options support both senses

Many ceph-related Boolean options offer the ability to both enable
and disable a feature. For all those that don't offer this, add
a new option so that they do.

Note that ceph_show_options()--which reports mount options currently
in effect--only reports the option if it is different from the
default value.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>

rbd: make ceph_parse_options() return a pointer

ceph_parse_options() takes the address of a pointer as an argument
and uses it to return the address of an allocated structure if
successful. With this interface is not evident at call sites that
the pointer is always initialized. Change the interface to return
the address instead (or a pointer-coded error code) to make the
validity of the returned pointer obvious.

Signed-off-by: Alex Elder <elder@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>

ceph: initialize client debugfs outside of monc->mutex

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>

libceph: create messenger with client

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>

libceph: fix parse options memory leak

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>

libceph: Create a new key type "ceph".

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>

libceph: Get secret from the kernel keys api when mounting with key=NAME.

Signed-off-by: Tommi Virtanen <tommi.virtanen@dreamhost.com>
Signed-off-by: Sage Weil <sage@newdream.net>

ceph: Move secret key parsing earlier.

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>

ceph: flush msgr_wq during mds_client shutdown

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>

libceph: add lingering request and watch/notify event framework

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>

ceph: don't crash when passed bad mount options

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>

ceph: factor out libceph from Ceph file system

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>