symlink target is useless for debug and can be very long. It's annoying
to show it in debugfs/mdsc.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

truncate_pagecache() may decrease inode's reference. This can cause
deadlock if inode's last reference is dropped and iput_final() wants
to evict the inode. (evict() calls inode_wait_for_writeback(), which
waits for ceph_writepages_start() to return).

The fix is use work thead to truncate dirty pages. Also add 'forced
umount' check to ceph_update_writeable_page(), which prevents new
pages getting dirty.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

When mds session gets killed, read/write operation may hang.
Client waits for Frw caps, but mds does not know what caps client
wants. To recover this, client sends an open request to mds. The
request will tell mds what caps client wants.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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

To access non-default filesystem, we just need to subscribe to
mdsmap.<MDS_NAMESPACE_ID> and add a new mount option for mds
namespace id.
Signed-off-by: NYan, Zheng <zyan@redhat.com>
[idryomov@gmail.com: switch to a new libceph API]
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>

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>

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>

Rename ceph_calc_pg_primary() to ceph_pg_to_acting_primary() to
emphasise that it returns acting primary.
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>

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

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

Starting the kernel client with cephx disabled and then enabling cephx
and restarting userspace daemons can result in a crash:

    [262671.478162] BUG: unable to handle kernel paging request at ffffebe000000000
    [262671.531460] IP: [<ffffffff811cd04a>] kfree+0x5a/0x130
    [262671.584334] PGD 0
    [262671.635847] Oops: 0000 [#1] SMP
    [262672.055841] CPU: 22 PID: 2961272 Comm: kworker/22:2 Not tainted 4.2.0-34-generic #39~14.04.1-Ubuntu
    [262672.162338] Hardware name: Dell Inc. PowerEdge R720/068CDY, BIOS 2.4.3 07/09/2014
    [262672.268937] Workqueue: ceph-msgr con_work [libceph]
    [262672.322290] task: ffff88081c2d0dc0 ti: ffff880149ae8000 task.ti: ffff880149ae8000
    [262672.428330] RIP: 0010:[<ffffffff811cd04a>]  [<ffffffff811cd04a>] kfree+0x5a/0x130
    [262672.535880] RSP: 0018:ffff880149aeba58  EFLAGS: 00010286
    [262672.589486] RAX: 000001e000000000 RBX: 0000000000000012 RCX: ffff8807e7461018
    [262672.695980] RDX: 000077ff80000000 RSI: ffff88081af2be04 RDI: 0000000000000012
    [262672.803668] RBP: ffff880149aeba78 R08: 0000000000000000 R09: 0000000000000000
    [262672.912299] R10: ffffebe000000000 R11: ffff880819a60e78 R12: ffff8800aec8df40
    [262673.021769] R13: ffffffffc035f70f R14: ffff8807e5b138e0 R15: ffff880da9785840
    [262673.131722] FS:  0000000000000000(0000) GS:ffff88081fac0000(0000) knlGS:0000000000000000
    [262673.245377] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    [262673.303281] CR2: ffffebe000000000 CR3: 0000000001c0d000 CR4: 00000000001406e0
    [262673.417556] Stack:
    [262673.472943]  ffff880149aeba88 ffff88081af2be04 ffff8800aec8df40 ffff88081af2be04
    [262673.583767]  ffff880149aeba98 ffffffffc035f70f ffff880149aebac8 ffff8800aec8df00
    [262673.694546]  ffff880149aebac8 ffffffffc035c89e ffff8807e5b138e0 ffff8805b047f800
    [262673.805230] Call Trace:
    [262673.859116]  [<ffffffffc035f70f>] ceph_x_destroy_authorizer+0x1f/0x50 [libceph]
    [262673.968705]  [<ffffffffc035c89e>] ceph_auth_destroy_authorizer+0x3e/0x60 [libceph]
    [262674.078852]  [<ffffffffc0352805>] put_osd+0x45/0x80 [libceph]
    [262674.134249]  [<ffffffffc035290e>] remove_osd+0xae/0x140 [libceph]
    [262674.189124]  [<ffffffffc0352aa3>] __reset_osd+0x103/0x150 [libceph]
    [262674.243749]  [<ffffffffc0354703>] kick_requests+0x223/0x460 [libceph]
    [262674.297485]  [<ffffffffc03559e2>] ceph_osdc_handle_map+0x282/0x5e0 [libceph]
    [262674.350813]  [<ffffffffc035022e>] dispatch+0x4e/0x720 [libceph]
    [262674.403312]  [<ffffffffc034bd91>] try_read+0x3d1/0x1090 [libceph]
    [262674.454712]  [<ffffffff810ab7c2>] ? dequeue_entity+0x152/0x690
    [262674.505096]  [<ffffffffc034cb1b>] con_work+0xcb/0x1300 [libceph]
    [262674.555104]  [<ffffffff8108fb3e>] process_one_work+0x14e/0x3d0
    [262674.604072]  [<ffffffff810901ea>] worker_thread+0x11a/0x470
    [262674.652187]  [<ffffffff810900d0>] ? rescuer_thread+0x310/0x310
    [262674.699022]  [<ffffffff810957a2>] kthread+0xd2/0xf0
    [262674.744494]  [<ffffffff810956d0>] ? kthread_create_on_node+0x1c0/0x1c0
    [262674.789543]  [<ffffffff817bd81f>] ret_from_fork+0x3f/0x70
    [262674.834094]  [<ffffffff810956d0>] ? kthread_create_on_node+0x1c0/0x1c0

What happens is the following:

    (1) new MON session is established
    (2) old "none" ac is destroyed
    (3) new "cephx" ac is constructed
    ...
    (4) old OSD session (w/ "none" authorizer) is put
          ceph_auth_destroy_authorizer(ac, osd->o_auth.authorizer)

osd->o_auth.authorizer in the "none" case is just a bare pointer into
ac, which contains a single static copy for all services.  By the time
we get to (4), "none" ac, freed in (2), is long gone.  On top of that,
a new vtable installed in (3) points us at ceph_x_destroy_authorizer(),
so we end up trying to destroy a "none" authorizer with a "cephx"
destructor operating on invalid memory!

To fix this, decouple authorizer destruction from ac and do away with
a single static "none" authorizer by making a copy for each OSD or MDS
session.  Authorizers themselves are independent of ac and so there is
no reason for destroy_authorizer() to be an ac op.  Make it an op on
the authorizer itself by turning ceph_authorizer into a real struct.

Fixes: http://tracker.ceph.com/issues/15447Reported-by: NAlan Zhang <alan.zhang@linux.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Reviewed-by: NSage Weil <sage@redhat.com>

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use kmem_cache_zalloc() instead of kmem_cache_alloc() with flag GFP_ZERO.
Signed-off-by: NGeliang Tang <geliangtang@163.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

If dentry has no lease, ceph_d_revalidate() previously return 0.
This causes VFS to invalidate the dentry and create a new dentry
for later lookup. Invalidating a dentry also detach any underneath
mount points. So mount point inside cephfs can disapear mystically
(even the mount point is not modified by other hosts).

The fix is using lookup request to revalidate dentry without lease.
This can partly solve the mount points disapear issue (as long as
the mount point is not modified by other hosts)
Signed-off-by: NYan, Zheng <zyan@redhat.com>

use vfs helper dget_parent() instead
Signed-off-by: NYan, Zheng <zyan@redhat.com>

When security is enabled, security module can call filesystem's
getxattr/setxattr callbacks during d_instantiate(). For cephfs,
d_instantiate() is usually called by MDS' dispatch thread, while
handling MDS reply. If the MDS reply does not include xattrs and
corresponding caps, getxattr/setxattr need to send a new request
to MDS and waits for the reply. This makes MDS' dispatch sleep,
nobody handles later MDS replies.

The fix is make sure lookup/atomic_open reply include xattrs and
corresponding caps. So getxattr can be handled by cached xattrs.
This requires some modification to both MDS and request message.
(Client tells MDS what caps it wants; MDS encodes proper caps in
the reply)

Smack security module may call setxattr during d_instantiate().
Unlike getxattr, we can't force MDS to issue CEPH_CAP_XATTR_EXCL
to us. So just make setxattr return error when called by MDS'
dispatch thread.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

It's uselese because MDS reply does not carry any vxattr.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

Now __ceph_open_session() only accepts closed client. An opened
client will tigger BUG_ON().
Signed-off-by: NYan, Zheng <zyan@redhat.com>

If page->mapping is NULL, releasepage() callback does not get called.
Remove the unnecessary NULL check to make static code analysis tool
happy
Signed-off-by: NYan, Zheng <zyan@redhat.com>

Directory inode's i_size is used by readdir cache.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

Readdir cache uses page cache to save dentry pointers. When adding
dentry pointers to middle of a page, we need to make sure the page
already exists. Otherwise the beginning part of the page will be
invalid pointers.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

ceph_empty_snapc->num_snaps == 0 at all times.  Passing such a snapc to
ceph_osdc_alloc_request() (possibly through ceph_osdc_new_request()) is
equivalent to passing NULL, as ceph_osdc_alloc_request() uses it only
for sizing the request message.

Further, in all four cases the subsequent ceph_osdc_build_request() is
passed NULL for snapc, meaning that 0 is encoded for seq and num_snaps
and making ceph_empty_snapc entirely useless.  The two cases where it
actually mattered were removed in commits 86056090 ("ceph: avoid
sending unnessesary FLUSHSNAP message") and 23078637 ("ceph: fix
queuing inode to mdsdir's snaprealm").
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Reviewed-by: NYan, Zheng <zyan@redhat.com>

A negative value rc compared to the positive value ENOENT in the
finish_read() function.
Signed-off-by: NAnton Protopopov <a.s.protopopov@gmail.com>
Signed-off-by: NYan, Zheng <zyan@redhat.com>

CURRENT_TIME macro is not appropriate for filesystems as it
doesn't use the right granularity for filesystem timestamps.
Use current_fs_time() instead.
Signed-off-by: NDeepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: NYan, Zheng <zyan@redhat.com>

This patch makes ceph_writepages_start() try using single OSD request
to write all dirty pages within a strip unit. When a nonconsecutive
dirty page is found, ceph_writepages_start() tries starting a new write
operation to existing OSD request. If it succeeds, it uses the new
operation to writeback the dirty page.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

ceph_osdc_start_request() never return -EOLDSNAP
Signed-off-by: NYan, Zheng <zyan@redhat.com>

When rbytes mount option is enabled, directory size is recursive
size. Recursive size is not updated instantly. This can cause
directory size to change between successive stat(1)
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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

It is currently hard-coded in the mon_client that mdsmap and monmap
subs are continuous, while osdmap sub is always "onetime".  To better
handle full clusters/pools in the osd_client, we need to be able to
issue continuous osdmap subs.  Revamp subs code to allow us to specify
for each sub whether it should be continuous or not.

Although not strictly required for the above, switch to SUBSCRIBE2
protocol while at it, eliminating the ambiguity between a request for
"every map since X" and a request for "just the latest" when we don't
have a map yet (i.e. have epoch 0).  SUBSCRIBE2 feature bit is now
required - it's been supported since pre-argonaut (2010).

Move "got mdsmap" call to the end of ceph_mdsc_handle_map() - calling
in before we validate the epoch and successfully install the new map
can mess up mon_client sub state.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

... and use d_add(dn, NULL) in case we need to hash a negative
unhashed rather than using d_rehash() directly.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

d_splice_alias() guarantees that it'll be always hashed
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Add support for the format change of MClientReply/MclientCaps.
Also add code that denies access to inodes with pool_ns layouts.
Signed-off-by: NYan, Zheng <zyan@redhat.com>
Reviewed-by: NSage Weil <sage@redhat.com>

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

ceph_osdc_alloc_request() returns NULL on error, it never returns error
pointers.

Fixes: 5be0389d ('ceph: re-send AIO write request when getting -EOLDSNAP error')
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>