First, this was racy anyway: d_release isn't called until well after the
dentry is unhashed. Second, this runs afoul of the recent dcache change
that clears d_parent prior to calling d_release (949854d0), causing a NULL
pointer dereference.
Signed-off-by: Sage Weil <sage@newdream.net>
This reverts commit 97d79b403e.
This fails to account for d_parent changes due to rename or disconnected
dentries due to submounts or NFS reexports.
Signed-off-by: Sage Weil <sage@newdream.net>
When creating a new dentry we now hold a reference to the parent
inode in the ceph_dentry. This is required due to the new RCU
changes from 949854d0, which set dentry->d_parent to NULL in d_kill before
calling the ->release() callback. If/when that behavior is changed, we can
revert this hack.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
We were forming a dirty list, and then queueing cap_snaps for each realm
_and_ its children, regardless of whether the children were already in the
dirty list. This meant we did it twice for some realms. Which in turn
meant we corrupted mdsc->snap_flush_list when the cap_snap was re-added to
the list it was already on, and could trigger an infinite loop.
We were also using recursion to do reach all the children, a no-no when
stack is limited.
Instead, (re)queue any children on the dirty list, avoiding processing
anything twice and avoiding any recursion.
Signed-off-by: Sage Weil <sage@newdream.net>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
ceph: avoid picking MDS that is not active
ceph: avoid immediate cap check after import
ceph: fix flushing of caps vs cap import
ceph: fix erroneous cap flush to non-auth mds
ceph: fix cap_wanted_delay_{min,max} mount option initialization
ceph: fix xattr rbtree search
ceph: fix getattr on directory when using norbytes
Ignore replication or auth frag data if it indicates an MDS that is not
active. This can happen if the MDS shuts down and the client has stale
data about the namespace distribution across the MDS cluster. If that's
the case, fall back to directing the request based on the auth cap (which
should always be accurate).
Signed-off-by: Sage Weil <sage@newdream.net>
The NODELAY flag avoids the heuristics that delay cap (issued/wanted)
release. There's no reason for that after we import a cap, and it kills
whatever benefit we get from those delays.
Signed-off-by: Sage Weil <sage@newdream.net>
If we are mid-flush and a cap is migrated to another node, we need to
resend the cap flush message to the new MDS, and do so with the original
flush_seq to avoid leaking across a sync boundary. Previously we didn't
redo the flush (we only flushed newly dirty data), which would cause a
later sync to hang forever.
Signed-off-by: Sage Weil <sage@newdream.net>
The int flushing is global and not clear on each iteration of the loop,
which can cause a second flush of caps to any MDSs with ids greater than
the auth.
Signed-off-by: Sage Weil <sage@newdream.net>
Fix xattr name comparison in rbtree search for strings that share a prefix.
The *name argument is null terminated, but the xattr name is not, so we
need to use strncmp, but that means adjusting for the case where name is
a prefix of xattr->name.
The corresponding case in __set_xattr() already handles this properly
(although in that case *name is also not null terminated).
Reported-by: Sergiy Kibrik <sakib@meta.ua>
Signed-off-by: Sage Weil <sage@newdream.net>
The norbytes mount option was broken, and when doing getattr
on a directory it return the rbytes instead of the number of
entities. This commit fixes it.
Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
rbd: fix cleanup when trying to mount inexistent image
net/ceph: make ceph_msgr_wq non-reentrant
ceph: fsc->*_wq's aren't used in memory reclaim path
ceph: Always free allocated memory in osdmap_decode()
ceph: Makefile: Remove unnessary code
ceph: associate requests with opening sessions
ceph: drop redundant r_mds field
ceph: implement DIRLAYOUTHASH feature to get dir layout from MDS
ceph: add dir_layout to inode
Remove the if and else conditional because the code is in mainline and there
is no need in it being there.
Also, Changed Makefile to use <modules>-y instead of <modules>-objs
because -objs is deprecated and not mentioned in
Documentation/kbuild/makefiles.txt.
Signed-off-by: Tracey Dent <tdent48227@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>
Associate request with sessions that aren't yep open. This makes the
debugfs mdsc request list more informative.
Signed-off-by: Sage Weil <sage@newdream.net>
The r_mds field is redundant, since we can find the same information at
r_session->s_mds, and when r_session is NULL then r_mds is meaningless.
Signed-off-by: Sage Weil <sage@newdream.net>
This implements the DIRLAYOUTHASH protocol feature, which passes the dir
layout over the wire from the MDS. This gives the client knowledge
of the correct hash function to use for mapping dentries among dir
fragments.
Note that if this feature is _not_ present on the client but is on the
MDS, the client may misdirect requests. This will result in a forward
and degrade performance. It may also result in inaccurate NFS filehandle
generation, which will prevent fh resolution when the inode is not present
in the client cache and the parent directories have been fragmented.
Signed-off-by: Sage Weil <sage@newdream.net>
Add a ceph_dir_layout to the inode, and calculate dentry hash values based
on the parent directory's specified dir_hash function. This is needed
because the old default Linux dcache hash function is extremely week and
leads to a poor distribution of files among dir fragments.
Signed-off-by: Sage Weil <sage@newdream.net>
Require filesystems be aware of .d_revalidate being called in rcu-walk
mode (nd->flags & LOOKUP_RCU). For now do a simple push down, returning
-ECHILD from all implementations.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Reduce some branches and memory accesses in dcache lookup by adding dentry
flags to indicate common d_ops are set, rather than having to check them.
This saves a pointer memory access (dentry->d_op) in common path lookup
situations, and saves another pointer load and branch in cases where we
have d_op but not the particular operation.
Patched with:
git grep -E '[.>]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)->d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&\1, \2);/' -i
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
RCU free the struct inode. This will allow:
- Subsequent store-free path walking patch. The inode must be consulted for
permissions when walking, so an RCU inode reference is a must.
- sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
to take i_lock no longer need to take sb_inode_list_lock to walk the list in
the first place. This will simplify and optimize locking.
- Could remove some nested trylock loops in dcache code
- Could potentially simplify things a bit in VM land. Do not need to take the
page lock to follow page->mapping.
The downsides of this is the performance cost of using RCU. In a simple
creat/unlink microbenchmark, performance drops by about 10% due to inability to
reuse cache-hot slab objects. As iterations increase and RCU freeing starts
kicking over, this increases to about 20%.
In cases where inode lifetimes are longer (ie. many inodes may be allocated
during the average life span of a single inode), a lot of this cache reuse is
not applicable, so the regression caused by this patch is smaller.
The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
however this adds some complexity to list walking and store-free path walking,
so I prefer to implement this at a later date, if it is shown to be a win in
real situations. I haven't found a regression in any non-micro benchmark so I
doubt it will be a problem.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Protect d_subdirs and d_child with d_lock, except in filesystems that aren't
using dcache_lock for these anyway (eg. using i_mutex).
Note: if we change the locking rule in future so that ->d_child protection is
provided only with ->d_parent->d_lock, it may allow us to reduce some locking.
But it would be an exception to an otherwise regular locking scheme, so we'd
have to see some good results. Probably not worthwhile.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Protect d_unhashed(dentry) condition with d_lock. This means keeping
DCACHE_UNHASHED bit in synch with hash manipulations.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Make d_count non-atomic and protect it with d_lock. This allows us to ensure a
0 refcount dentry remains 0 without dcache_lock. It is also fairly natural when
we start protecting many other dentry members with d_lock.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
For read operation, we have to set the argument _write_ of get_user_pages
to 1 since we will write data to pages. Also, we need to SetPageDirty before
releasing these pages.
Signed-off-by: Henry C Chang <henry_c_chang@tcloudcomputing.com>
Signed-off-by: Sage Weil <sage@newdream.net>
The fh_to_dentry etc. methods use ceph_init_dentry(), which assumes that
d_parent is defined. It isn't for those callers, so check!
Signed-off-by: Sage Weil <sage@newdream.net>
The user buffer may be 512-byte aligned, not page-aligned. We were
assuming the buffer was page-aligned and only accounting for
non-page-aligned io offsets.
Signed-off-by: Henry C Chang <henry_c_chang@tcloudcomputing.com>
Signed-off-by: Sage Weil <sage@newdream.net>
Fill in the local lock with response data if appropriate,
and don't call posix_lock_file when reading locks.
Signed-off-by: Herb Shiu <herb_shiu@tcloudcomputing.com>
Acked-by: Greg Farnum <gregf@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
Previously the kernel client incorrectly assumed everything was a directory.
Signed-off-by: Herb Shiu <herb_shiu@tcloudcomputing.com>
Acked-by: Greg Farnum <gregf@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
last may be NULL, but we dereference it in the else branch without
checking. Normally it doesn't trigger because last == NULL when fpos == 2,
but it could happen on a newly opened dir if the user seeks forward.
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
ceph: fix readdir EOVERFLOW on 32-bit archs
ceph: fix frag offset for non-leftmost frags
ceph: fix dangling pointer
ceph: explicitly specify page alignment in network messages
ceph: make page alignment explicit in osd interface
ceph: fix comment, remove extraneous args
ceph: fix update of ctime from MDS
ceph: fix version check on racing inode updates
ceph: fix uid/gid on resent mds requests
ceph: fix rdcache_gen usage and invalidate
ceph: re-request max_size if cap auth changes
ceph: only let auth caps update max_size
ceph: fix open for write on clustered mds
ceph: fix bad pointer dereference in ceph_fill_trace
ceph: fix small seq message skipping
Revert "ceph: update issue_seq on cap grant"
One of the readdir filldir_t callers was passing the raw ceph 64-bit ino
instead of the hashed 32-bit one, producing an EOVERFLOW in the filler
callback. Fix this by calling the ceph_vino_to_ino() helper to do the
conversion.
Reported-by: Jan Smets <jan.smets@alcatel-lucent.com>
Tested-by: Jan Smets <jan.smets@alcatel-lucent.com>
Signed-off-by: Sage Weil <sage@newdream.net>
The big kernel lock has been removed from all these files at some point,
leaving only the #include.
Remove this too as a cleanup.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We start at offset 2 for the leftmost frag, and 0 for subsequent frags.
When we reach the end (rightmost), we go back to 2. This fixes readdir on
fragmented (large) directories.
Signed-off-by: Sage Weil <sage@newdream.net>
We used to infer alignment of IOs within a page based on the file offset,
which assumed they matched. This broke with direct IO that was not aligned
to pages (e.g., 512-byte aligned IO). We were also trusting the alignment
specified in the OSD reply, which could have been adjusted by the server.
Explicitly specify the page alignment when setting up OSD IO requests.
Signed-off-by: Sage Weil <sage@newdream.net>
The client can have a newer ctime than the MDS due to AUTH_EXCL and
XATTR_EXCL caps as well; update the check in ceph_fill_file_time
appropriately.
This fixes cases where ctime/mtime goes backward under the right sequence
of local updates (e.g. chmod) and mds replies (e.g. subsequent stat that
goes to the MDS).
Signed-off-by: Sage Weil <sage@newdream.net>
We may get updates on the same inode from multiple MDSs; generally we only
pay attention if the update is newer than what we already have. The
exception is when an MDS sense unstable information, in which case we
always update.
The old > check got this wrong when our version was odd (e.g. 3) and the
reply version was even (e.g. 2): the older stale (v2) info would be
applied. Fixed and clarified the comment.
Signed-off-by: Sage Weil <sage@newdream.net>
MDS requests can be rebuilt and resent in non-process context, but were
filling in uid/gid from current_fsuid/gid. Put that information in the
request struct on request setup.
This fixes incorrect (and root) uid/gid getting set for requests that
are forwarded between MDSs, usually due to metadata migrations.
Signed-off-by: Sage Weil <sage@newdream.net>
We used to use rdcache_gen to indicate whether we "might" have cached
pages. Now we just look at the mapping to determine that. However, some
old behavior remains from that transition.
First, rdcache_gen == 0 no longer means we have no pages. That can happen
at any time (presumably when we carry FILE_CACHE). We should not reset it
to zero, and we should not check that it is zero.
That means that the only purpose for rdcache_revoking is to resolve races
between new issues of FILE_CACHE and an async invalidate. If they are
equal, we should invalidate. On success, we decrement rdcache_revoking,
so that it is no longer equal to rdcache_gen. Similarly, if we success
in doing a sync invalidate, set revoking = gen - 1. (This is a small
optimization to avoid doing unnecessary invalidate work and does not
affect correctness.)
Signed-off-by: Sage Weil <sage@newdream.net>
