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path: root/fs/ceph/mds_client.c
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2017-09-19ceph: avoid panic in create_session_open_msg() if utsname() returns NULLYan, Zheng1-3/+4
utsname() can return NULL while process is exiting. Kernel releases file locks during process exits. We send request to mds when releasing file lock. So it's possible that we open mds session while process is exiting. utsname() is called in create_session_open_msg(). Link: http://tracker.ceph.com/issues/21275 Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> [idryomov@gmail.com: drop utsname.h include from mds_client.c] Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-09-06ceph: adjust 36 checks for NULL pointersMarkus Elfring1-11/+11
The script “checkpatch.pl” pointed information out like the following. Comparison to NULL could be written ... Thus fix the affected source code places. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Reviewed-by: Yan, Zheng <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-09-06ceph: properly set snap follows for cap reconnectYan, Zheng1-1/+1
Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-09-06ceph: send LSSNAP request to auth mds of directory inodeYan, Zheng1-3/+10
Snapdir inode has no capability. __choose_mds() should choose mds base on capabilities of snapdir's parent inode. Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-07-07ceph: avoid invalid memory dereference in the middle of umountYan, Zheng1-2/+2
extra_mon_dispatch() and debugfs' foo_show functions dereference fsc->mdsc. we should clean up fsc->client->extra_mon_dispatch and debugfs before destroying fsc->mds. Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-06-14ceph: use current_kernel_time() to get request time stampYan, Zheng1-3/+1
ceph uses ktime_get_real_ts() to get request time stamp. In most other cases, current_kernel_time() is used to get time stamp for filesystem operations (called by current_time()). There is granularity difference between ktime_get_real_ts() and current_kernel_time(). The later one can be up to one jiffy behind the former one. This can causes inode's ctime to go back. Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-10Merge tag 'ceph-for-4.12-rc1' of git://github.com/ceph/ceph-clientLinus Torvalds1-16/+59
Pull ceph updates from Ilya Dryomov: "The two main items are support for disabling automatic rbd exclusive lock transfers from myself and the long awaited -ENOSPC handling series from Jeff. The former will allow rbd users to take advantage of exclusive lock's built-in blacklist/break-lock functionality while staying in control of who owns the lock. With the latter in place, we will abort filesystem writes on -ENOSPC instead of having them block indefinitely. Beyond that we've got the usual pile of filesystem fixes from Zheng, some refcount_t conversion patches from Elena and a patch for an ancient open() flags handling bug from Alexander" * tag 'ceph-for-4.12-rc1' of git://github.com/ceph/ceph-client: (31 commits) ceph: fix memory leak in __ceph_setxattr() ceph: fix file open flags on ppc64 ceph: choose readdir frag based on previous readdir reply rbd: exclusive map option rbd: return ResponseMessage result from rbd_handle_request_lock() rbd: kill rbd_is_lock_supported() rbd: support updating the lock cookie without releasing the lock rbd: store lock cookie rbd: ignore unlock errors rbd: fix error handling around rbd_init_disk() rbd: move rbd_unregister_watch() call into rbd_dev_image_release() rbd: move rbd_dev_destroy() call out of rbd_dev_image_release() ceph: when seeing write errors on an inode, switch to sync writes Revert "ceph: SetPageError() for writeback pages if writepages fails" ceph: handle epoch barriers in cap messages libceph: add an epoch_barrier field to struct ceph_osd_client libceph: abort already submitted but abortable requests when map or pool goes full libceph: allow requests to return immediately on full conditions if caller wishes libceph: remove req->r_replay_version ceph: make seeky readdir more efficient ...
2017-05-08fs: ceph: CURRENT_TIME with ktime_get_real_ts()Deepa Dinamani1-1/+3
CURRENT_TIME is not y2038 safe. The macro will be deleted and all the references to it will be replaced by ktime_get_* apis. struct timespec is also not y2038 safe. Retain timespec for timestamp representation here as ceph uses it internally everywhere. These references will be changed to use struct timespec64 in a separate patch. The current_fs_time() api is being changed to use vfs struct inode* as an argument instead of struct super_block*. Set the new mds client request r_stamp field using ktime_get_real_ts() instead of using current_fs_time(). Also, since r_stamp is used as mtime on the server, use timespec_trunc() to truncate the timestamp, using the right granularity from the superblock. This api will be transitioned to be y2038 safe along with vfs. Link: http://lkml.kernel.org/r/1491613030-11599-5-git-send-email-deepa.kernel@gmail.com Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> M: Ilya Dryomov <idryomov@gmail.com> M: "Yan, Zheng" <zyan@redhat.com> M: Sage Weil <sage@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-04ceph: handle epoch barriers in cap messagesJeff Layton1-0/+20
Have the client store and update the osdc epoch_barrier when a cap message comes in with one. When sending cap messages, send the epoch barrier as well. This allows clients to inform servers that their released caps may not be used until a particular OSD map epoch. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: "Yan, Zheng” <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04ceph: make seeky readdir more efficientYan, Zheng1-0/+1
Current cephfs client uses string to indicate start position of readdir. The string is last entry of previous readdir reply. This approach does not work for seeky readdir because we can not easily convert the new postion to a string. For seeky readdir, mds needs to return dentries from the beginning. Client keeps retrying if the reply does not contain the dentry it wants. In current version of ceph, mds sorts CDentry in its cache in hash order. Client also uses dentry hash to compose dir postion. For seeky readdir, if client passes the hash part of dir postion to mds. mds can avoid replying useless dentries. Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04ceph: close stopped mds' sessionYan, Zheng1-0/+16
If a mds has stopped, close its session and clean up its session requests/caps. The process is similar to handling SESSION_CLOSE initiated by mds. Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04ceph: fix potential use-after-freeYan, Zheng1-2/+8
__unregister_session() free the session if it drops the last reference. We should grab an extra reference if we want to use session after __unregister_session(). Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04ceph: allow connecting to mds whose rank >= mdsmap::m_max_mdsYan, Zheng1-5/+5
mdsmap::m_max_mds is the expected count of active mds. It's not the max rank of active mds. User can decrease mdsmap::m_max_mds, but does not stop mds whose rank >= mdsmap::m_max_mds. Signed-off-by: "Yan, Zheng" <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04libceph: convert ceph_pagelist.refcnt from atomic_t to refcount_tElena Reshetova1-1/+1
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-05-04ceph: convert ceph_mds_session.s_ref from atomic_t to refcount_tElena Reshetova1-9/+9
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-02-23ceph: tidy some white space in get_nonsnap_parent()Dan Carpenter1-2/+3
The white space here seems slightly messed up. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-02-20ceph: remove req from unsafe list when unregistering itJeff Layton1-2/+3
There's no reason a request should ever be on a s_unsafe list but not in the request tree. Cc: stable@vger.kernel.org Link: http://tracker.ceph.com/issues/18474 Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Yan, Zheng <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-02-20ceph: add a new flag to indicate whether parent is lockedJeff Layton1-12/+12
struct ceph_mds_request has an r_locked_dir pointer, which is set to indicate the parent inode and that its i_rwsem is locked. In some critical places, we need to be able to indicate the parent inode to the request handling code, even when its i_rwsem may not be locked. Most of the code that operates on r_locked_dir doesn't require that the i_rwsem be locked. We only really need it to handle manipulation of the dcache. The rest (filling of the inode, updating dentry leases, etc.) already has its own locking. Add a new r_req_flags bit that indicates whether the parent is locked when doing the request, and rename the pointer to "r_parent". For now, all the places that set r_parent also set this flag, but that will change in a later patch. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Yan, Zheng <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-02-20ceph: convert bools in ceph_mds_request to a new r_req_flags fieldJeff Layton1-22/+25
Currently, we have a bunch of bool flags in struct ceph_mds_request. We need more flags though, but each bool takes (at least) a byte. Those add up over time. Merge all of the existing bools in this struct into a single unsigned long, and use the set/test/clear_bit macros to manipulate them. These are atomic operations, but that is required here to prevent load/modify/store races. The existing flags are protected by different locks, so we can't rely on them for that purpose. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Yan, Zheng <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-02-20ceph: drop session argument to ceph_fill_traceJeff Layton1-1/+1
Just get it from r_session since that's what's always passed in. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Yan, Zheng <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-02-20ceph: cleanup ACCESS_ONCE -> READ_ONCESeraphime Kirkovski1-5/+5
This removes the uses of ACCESS_ONCE in favor of READ_ONCE Signed-off-by: Seraphime Kirkovski <kirkseraph@gmail.com> Signed-off-by: Yan, Zheng <zyan@redhat.com>
2017-02-20ceph: pass parent inode info to ceph_encode_dentry_release if we have itJeff Layton1-2/+5
If we have a parent inode reference already, then we don't need to go back up the directory tree to find one. Link: http://tracker.ceph.com/issues/18148 Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Yan, Zheng <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-02-20ceph: pass parent dir ino info to build_dentry_pathJeff Layton1-7/+9
In the event that we have a parent inode reference in the request, we can use that instead of mucking about in the dcache. Pass any parent inode info we have down to build_dentry_path so it can make use of it. Link: http://tracker.ceph.com/issues/18148 Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Yan, Zheng <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-02-20ceph: clean up unsafe d_parent accesses in build_dentry_pathJeff Layton1-2/+7
While we hold a reference to the dentry when build_dentry_path is called, we could end up racing with a rename that changes d_parent. Handle that situation correctly, by using the rcu_read_lock to ensure that the parent dentry and inode stick around long enough to safely check ceph_snap and ceph_ino. Link: http://tracker.ceph.com/issues/18148 Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Yan, Zheng <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-02-20ceph: clean up unsafe d_parent access in __choose_mdsJeff Layton1-22/+42
__choose_mds exists to pick an MDS to use when issuing a call. Doing that typically involves picking an inode and using the authoritative MDS for it. In most cases, that's pretty straightforward, as we are using an inode to which we hold a reference (usually represented by r_dentry or r_inode in the request). In the case of a snapshotted directory however, we need to fetch the non-snapped parent, which involves walking back up the parents in the tree. The dentries in the snapshot dir are effectively frozen but the overall parent is _not_, and could vanish if a concurrent rename were to occur. Clean this code up and take special care to ensure the validity of the entries we're working with. First, try to use the inode in r_locked_dir if one exists. If not and all we have is r_dentry, then we have to walk back up the tree. Use the rcu_read_lock for this so we can ensure that any d_parent we find won't go away, and take extra care to deal with the possibility that the dentries could go negative. Change get_nonsnap_parent to return an inode, and take a reference to that inode before returning (if any). Change all of the other places where we set "inode" in __choose_mds to also take a reference, and then call iput on that inode before exiting the function. Link: http://tracker.ceph.com/issues/18148 Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Yan, Zheng <zyan@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-01-18ceph: fix bad endianness handling in parse_reply_info_extraJeff Layton1-4/+5
sparse says: fs/ceph/mds_client.c:291:23: warning: restricted __le32 degrades to integer fs/ceph/mds_client.c:293:28: warning: restricted __le32 degrades to integer fs/ceph/mds_client.c:294:28: warning: restricted __le32 degrades to integer fs/ceph/mds_client.c:296:28: warning: restricted __le32 degrades to integer The op value is __le32, so we need to convert it before comparing it. Cc: stable@vger.kernel.org # needs backporting for < 3.14 Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Sage Weil <sage@redhat.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2017-01-12ceph: fix mds cluster availability checkYan, Zheng1-0/+5
We should apply the check after getting the initial mdsmap. Fixes: e9e427f0a14f ("ceph: check availability of mds cluster on mount") Link: http://tracker.ceph.com/issues/18161 Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-12-12ceph: check availability of mds cluster on mountYan, Zheng1-5/+14
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-12-12libceph: drop len argument of *verify_authorizer_reply()Ilya Dryomov1-2/+2
The length of the reply is protocol-dependent - for cephx it's ceph_x_authorize_reply. Nothing sensible can be passed from the messenger layer anyway. Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Reviewed-by: Sage Weil <sage@redhat.com>
2016-10-03ceph: use list_move instead of list_del/list_addWei Yongjun1-2/+1
Using list_move() instead of list_del() + list_add(). Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2016-10-03ceph: handle CEPH_SESSION_REJECT messageYan, Zheng1-5/+22
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-08-09ceph: initialize pathbase in the !dentry case in encode_caps_cb()Ilya Dryomov1-0/+1
pathbase is the base inode; set it to 0 if we've got no path. Coverity-id: 146348 Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Reviewed-by: Alex Elder <elder@linaro.org>
2016-08-02Merge tag 'ceph-for-4.8-rc1' of git://github.com/ceph/ceph-clientLinus Torvalds1-169/+189
Pull Ceph updates from Ilya Dryomov: "The highlights are: - RADOS namespace support in libceph and CephFS (Zheng Yan and myself). The stopgaps added in 4.5 to deny access to inodes in namespaces are removed and CEPH_FEATURE_FS_FILE_LAYOUT_V2 feature bit is now fully supported - A large rework of the MDS cap flushing code (Zheng Yan) - Handle some of ->d_revalidate() in RCU mode (Jeff Layton). We were overly pessimistic before, bailing at the first sight of LOOKUP_RCU On top of that we've got a few CephFS bug fixes, a couple of cleanups and Arnd's workaround for a weird genksyms issue" * tag 'ceph-for-4.8-rc1' of git://github.com/ceph/ceph-client: (34 commits) ceph: fix symbol versioning for ceph_monc_do_statfs ceph: Correctly return NXIO errors from ceph_llseek ceph: Mark the file cache as unreclaimable ceph: optimize cap flush waiting ceph: cleanup ceph_flush_snaps() ceph: kick cap flushes before sending other cap message ceph: introduce an inode flag to indicates if snapflush is needed ceph: avoid sending duplicated cap flush message ceph: unify cap flush and snapcap flush ceph: use list instead of rbtree to track cap flushes ceph: update types of some local varibles ceph: include 'follows' of pending snapflush in cap reconnect message ceph: update cap reconnect message to version 3 ceph: mount non-default filesystem by name libceph: fsmap.user subscription support ceph: handle LOOKUP_RCU in ceph_d_revalidate ceph: allow dentry_lease_is_valid to work under RCU walk ceph: clear d_fsinfo pointer under d_lock ceph: remove ceph_mdsc_lease_release ceph: don't use ->d_time ...
2016-07-28ceph: optimize cap flush waitingYan, Zheng1-0/+8
Add a 'wake' flag to ceph_cap_flush struct, which indicates if there is someone waiting for it to finish. When getting flush ack message, we check the 'wake' flag in corresponding ceph_cap_flush struct to decide if we should wake up waiters. One corner case is that the acked cap flush has 'wake' flags is set, but it is not the first one on the flushing list. We do not wake up waiters in this case, set 'wake' flags of preceding ceph_cap_flush struct instead Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28ceph: unify cap flush and snapcap flushYan, Zheng1-71/+6
This patch includes following changes - Assign flush tid to snapcap flush - Remove session's s_cap_snaps_flushing list. Add inode to session's s_cap_flushing list instead. Inode is removed from the list when there is no pending snapcap flush or cap flush. - make __kick_flushing_caps() re-send both snapcap flushes and cap flushes. Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28ceph: use list instead of rbtree to track cap flushesYan, Zheng1-21/+20
We don't have requirement of searching cap flush by TID. In most cases, we just need to know TID of the oldest cap flush. List is ideal for this usage. Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28ceph: include 'follows' of pending snapflush in cap reconnect messageYan, Zheng1-1/+16
This helps the recovering MDS to reconstruct the internal states that tracking pending snapflush. Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28ceph: update cap reconnect message to version 3Yan, Zheng1-21/+47
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28ceph: mount non-default filesystem by nameYan, Zheng1-2/+85
To mount non-default filesytem, user currently needs to provide mds namespace ID. This is inconvenience. This patch makes user be able to mount filesystem by name. If user wants to mount non-default filesystem. Client first subscribes to fsmap.user. Subscribe to mdsmap.<ID> after getting ID of filesystem. Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-07-28ceph: remove ceph_mdsc_lease_releaseJeff Layton1-41/+0
Nothing calls it. Signed-off-by: Jeff Layton <jlayton@redhat.com> Reviewed-by: Yan, Zheng <zyan@redhat.com>
2016-07-28ceph: don't use ->d_timeMiklos Szeredi1-2/+2
Pretty simple: just use ceph_dentry_info.time instead (which was already there, unused). Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-28ceph: rados pool namespace supportYan, Zheng1-12/+7
This patch adds codes that decode pool namespace information in cap message and request reply. Pool namespace is saved in i_layout, it will be passed to libceph when doing read/write. Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-06-10vfs: make the string hashes salt the hashLinus Torvalds1-1/+1
We always mixed in the parent pointer into the dentry name hash, but we did it late at lookup time. It turns out that we can simplify that lookup-time action by salting the hash with the parent pointer early instead of late. A few other users of our string hashes also wanted to mix in their own pointers into the hash, and those are updated to use the same mechanism. Hash users that don't have any particular initial salt can just use the NULL pointer as a no-salt. Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: George Spelvin <linux@sciencehorizons.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-26ceph: fix wake_up_session_cb()Yan, Zheng1-1/+1
We should reset i_requested_max_size before waking the waiters. (zero i_requested_max_size make waiter re-request the max size) Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-05-26ceph: using hash value to compose dentry offsetYan, Zheng1-0/+1
If MDS sorts dentries in dirfrag in hash order, we use hash value to compose dentry offset. dentry offset is: (0xff << 52) | ((24 bits hash) << 28) | (the nth entry hash hash collision) This offset is stable across directory fragmentation. This alos means there is no need to reset readdir offset if directory get fragmented in the middle of readdir. Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-05-26ceph: record 'offset' for each entry of readdir resultYan, Zheng1-0/+2
This is preparation for using hash value as dentry 'offset' Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-05-26ceph: define 'end/complete' in readdir reply as bit flagsYan, Zheng1-2/+5
Set a flag in readdir request, which indicates that client interprets 'end/complete' as bit flags. So that mds can reply additional flags in readdir reply. Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-05-26ceph: define struct for dir entry in readdir replyYan, Zheng1-23/+19
This avoids defining multiple arrays for entries in readdir reply Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-05-26ceph: report mount root in session metadataYan, Zheng1-1/+3
Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-05-26ceph: don't call truncate_pagecache in ceph_writepages_startYan, Zheng1-7/+15
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: Yan, Zheng <zyan@redhat.com>