This changes the vfs dentry hashing to mix in the parent pointer at the
_beginning_ of the hash, rather than at the end.
That actually improves both the hash and the code generation, because we
can move more of the computation to the "static" part of the dcache
setup, and do less at lookup runtime.
It turns out that a lot of other hash users also really wanted to mix in
a base pointer as a 'salt' for the hash, and so the slightly extended
interface ends up working well for other cases too.
Users that want a string hash that is purely about the string pass in a
'salt' pointer of NULL.
* merge branch 'salted-string-hash':
fs/dcache.c: Save one 32-bit multiply in dcache lookup
vfs: make the string hashes salt the hash
->atomic_open() can be given an in-lookup dentry *or* a negative one
found in dcache. Use d_in_lookup() to tell one from another, rather
than d_unhashed().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull vfs fixes from Al Viro:
"Tmpfs readdir throughput regression fix (this cycle) + some -stable
fodder all over the place.
One missing bit is Miklos' tonight locks.c fix - NFS folks had already
grabbed that one by the time I woke up ;-)"
[ The locks.c fix came through the nfsd tree just moments ago ]
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
namespace: update event counter when umounting a deleted dentry
9p: use file_dentry()
ceph: fix d_obtain_alias() misuses
lockless next_positive()
libfs.c: new helper - next_positive()
dcache_{readdir,dir_lseek}(): don't bother with nested ->d_lock
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>
There are several issues in fscache revalidation code.
- In ceph_revalidate_work(), fscache_invalidate() is called when
fscache_check_consistency() return 0. This is complete wrong
because 0 means cache is valid.
- Handle_cap_grant() calls ceph_queue_revalidate() if client
already has CAP_FILE_CACHE. This code is confusing. Client
should revalidate the cache each time it got CAP_FILE_CACHE
anew.
- In Handle_cap_grant(), fscache_invalidate() is called if MDS
revokes CAP_FILE_CACHE. This is inconsistency with the case
that inode get evicted. In the later case, the cache is not
discarded. Client may use the cache when inode is reloaded.
This patch moves the fscache revalidation into ceph_get_caps().
Client revalidates the cache after it gets CAP_FILE_CACHE.
i_rdcache_gen should keep constance while CAP_FILE_CACHE is
used. If i_fscache_gen is not equal to i_rdcache_gen, client
needs to check cache's consistency.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
All other filesystems do not add dirty pages to fscache. They all
disable fscache when inode is opened for write. Only ceph adds
dirty pages to fscache, but the code is buggy.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
For the benefit of every single caller, take osdc instead of map.
Also, now that osdc->osdmap can't ever be NULL, drop the check.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Pull vfs fixes from Al Viro:
"Followups to the parallel lookup work:
- update docs
- restore killability of the places that used to take ->i_mutex
killably now that we have down_write_killable() merged
- Additionally, it turns out that I missed a prerequisite for
security_d_instantiate() stuff - ->getxattr() wasn't the only thing
that could be called before dentry is attached to inode; with smack
we needed the same treatment applied to ->setxattr() as well"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
switch ->setxattr() to passing dentry and inode separately
switch xattr_handler->set() to passing dentry and inode separately
restore killability of old mutex_lock_killable(&inode->i_mutex) users
add down_write_killable_nested()
update D/f/directory-locking
Pull Ceph updates from Sage Weil:
"This changeset has a few main parts:
- Ilya has finished a huge refactoring effort to sync up the
client-side logic in libceph with the user-space client code, which
has evolved significantly over the last couple years, with lots of
additional behaviors (e.g., how requests are handled when cluster
is full and transitions from full to non-full).
This structure of the code is more closely aligned with userspace
now such that it will be much easier to maintain going forward when
behavior changes take place. There are some locking improvements
bundled in as well.
- Zheng adds multi-filesystem support (multiple namespaces within the
same Ceph cluster)
- Zheng has changed the readdir offsets and directory enumeration so
that dentry offsets are hash-based and therefore stable across
directory fragmentation events on the MDS.
- Zheng has a smorgasbord of bug fixes across fs/ceph"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (71 commits)
ceph: fix wake_up_session_cb()
ceph: don't use truncate_pagecache() to invalidate read cache
ceph: SetPageError() for writeback pages if writepages fails
ceph: handle interrupted ceph_writepage()
ceph: make ceph_update_writeable_page() uninterruptible
libceph: make ceph_osdc_wait_request() uninterruptible
ceph: handle -EAGAIN returned by ceph_update_writeable_page()
ceph: make fault/page_mkwrite return VM_FAULT_OOM for -ENOMEM
ceph: block non-fatal signals for fault/page_mkwrite
ceph: make logical calculation functions return bool
ceph: tolerate bad i_size for symlink inode
ceph: improve fragtree change detection
ceph: keep leaf frag when updating fragtree
ceph: fix dir_auth check in ceph_fill_dirfrag()
ceph: don't assume frag tree splits in mds reply are sorted
ceph: fix inode reference leak
ceph: using hash value to compose dentry offset
ceph: don't forbid marking directory complete after forward seek
ceph: record 'offset' for each entry of readdir result
ceph: define 'end/complete' in readdir reply as bit flags
...
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>
truncate_pagecache() drops dirty pages, it's dangerous to use it
to invalidate read cache. Besides, we shouldn't start invalidating
read cache while there are buffer writers. Because buffer writers
may add dirty pages later.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
writepage() can be interrupted when it's called by direct memory
reclaimer (the direct memory relaimer is killed). To avoid lossing
data, we redirty the page.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
ceph_update_writeable_page() is used by ceph_write_begin(). It beaks
atomicity of write operation if it's interruptible.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
when ceph_update_writeable_page() return -EAGAIN, caller should
lock the page and call ceph_update_writeable_page() again.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Fault and page_mkwrite are supposed to be uninterruptable. But they
call ceph functions that are interruptible. So they should block
signals before calling functions that are interruptible
Signed-off-by: Yan, Zheng <zyan@redhat.com>
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>
Nodes in i_fragtree are sorted according to ceph_compare_frag().
It means frag node in i_fragtree always follow its direct parent
node. To check if a leaf node is valid, we just need to check if
it's child of previous split node.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
The algorithm that updates i_fragtree relies on that the frag tree
splits in mds reply are of the same order of i_fragtree. This is not
true because current MDS encodes frag tree splits in ascending order
of (unsigned)frag_t. But nodes in i_fragtree are sorted according to
ceph_frag_compare().
The fix is sort the frag tree splits first, then updates i_fragtree.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
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>
Forward seek within same frag does not update fi->last_name, it will
not affect contents of later readdir reply. So there is no need to
forbid marking directory complete
Signed-off-by: Yan, Zheng <zyan@redhat.com>
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>
Setxattr with NULL value and XATTR_REPLACE flag should be equivalent
to removexattr. But current MDS does not support deleting vxattrs through
MDS_OP_SETXATTR request. The workaround is sending MDS_OP_RMXATTR request
if setxattr actually removs xattr.
Signed-off-by: Yan, 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: Yan, 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: Yan, 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: Yan, Zheng <zyan@redhat.com>
[idryomov@gmail.com: switch to a new libceph API]
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
This is a major sync up, up to ~Jewel. The highlights are:
- per-session request trees (vs a global per-client tree)
- per-session locking (vs a global per-client rwlock)
- homeless OSD session
- no ad-hoc global per-client lists
- support for pool quotas
- foundation for watch/notify v2 support
- foundation for map check (pool deletion detection) support
The switchover is incomplete: lingering requests can be setup and
teared down but aren't ever reestablished. This functionality is
restored with the introduction of the new lingering infrastructure
(ceph_osd_linger_request, linger_work, etc) in a later commit.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
If you specify ACK | ONDISK and set ->r_unsafe_callback, both
->r_callback and ->r_unsafe_callback(true) are called on ack. This is
very confusing. Redo this so that only one of them is called:
->r_unsafe_callback(true), on ack
->r_unsafe_callback(false), on commit
or
->r_callback, on ack|commit
Decode everything in decode_MOSDOpReply() to reduce clutter.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
finish_read(), its only user, uses it to get to hdr.data_len, which is
what ->r_result is set to on success. This gains us the ability to
safely call callbacks from contexts other than reply, e.g. map check.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The crux of this is getting rid of ceph_osdc_build_request(), so that
MOSDOp can be encoded not before but after calc_target() calculates the
actual target. Encoding now happens within ceph_osdc_start_request().
Also nuked is the accompanying bunch of pointers into the encoded
buffer that was used to update fields on each send - instead, the
entire front is re-encoded. If we want to support target->name_len !=
base->name_len in the future, there is no other way, because oid is
surrounded by other fields in the encoded buffer.
Encoding OSD ops and adding data items to the request message were
mixed together in osd_req_encode_op(). While we want to re-encode OSD
ops, we don't want to add duplicate data items to the message when
resending, so all call to ceph_osdc_msg_data_add() are factored out
into a new setup_request_data().
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Introduce ceph_osd_request_target, containing all mapping-related
fields of ceph_osd_request and calc_target() for calculating mappings
and populating it.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Rename ceph_calc_pg_primary() to ceph_pg_to_acting_primary() to
emphasise that it returns acting primary.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
