Commit Graph

46 Commits

Author SHA1 Message Date
Nick Piggin
b74c79e993 fs: provide rcu-walk aware permission i_ops
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:29 +11:00
Nick Piggin
fa0d7e3de6 fs: icache RCU free inodes
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>
2011-01-07 17:50:26 +11:00
Nick Piggin
b5c84bf6f6 fs: dcache remove dcache_lock
dcache_lock no longer protects anything. remove it.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:23 +11:00
Nick Piggin
2fd6b7f507 fs: dcache scale subdirs
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>
2011-01-07 17:50:21 +11:00
Nick Piggin
b7ab39f631 fs: dcache scale dentry refcount
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>
2011-01-07 17:50:21 +11:00
Linus Torvalds
76db8ac45f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
* '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"
2010-11-19 15:32:22 -08:00
Arnd Bergmann
451a3c24b0 BKL: remove extraneous #include <smp_lock.h>
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>
2010-11-17 08:59:32 -08:00
Sage Weil
b7495fc2ff ceph: make page alignment explicit in osd interface
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>
2010-11-09 12:43:12 -08:00
Sage Weil
d8672d64b8 ceph: fix update of ctime from MDS
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>
2010-11-08 09:24:34 -08:00
Sage Weil
8bd59e0188 ceph: fix version check on racing inode updates
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>
2010-11-08 09:23:12 -08:00
Sage Weil
cd045cb42a ceph: fix rdcache_gen usage and invalidate
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>
2010-11-08 07:29:05 -08:00
Sage Weil
912a9b0319 ceph: only let auth caps update max_size
Only the auth MDS has a meaningful max_size value for us, so only update it
in fill_inode if we're being issued an auth cap.  Otherwise, a random
stat result from a non-auth MDS can clobber a meaningful max_size, get
the client<->mds cap state out of sync, and make writes hang.

Specifically, even if the client re-requests a larger max_size (which it
will), the MDS won't respond because as far as it knows we already have a
sufficiently large value.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-11-07 09:39:21 -08:00
Sage Weil
d8b16b3d1c ceph: fix bad pointer dereference in ceph_fill_trace
We dereference *in a few lines down, but only set it on rename.  It is
apparently pretty rare for this to trigger, but I have been hitting it
with a clustered MDSs.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-11-07 08:40:43 -08:00
Yehuda Sadeh
3d14c5d2b6 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>
2010-10-20 15:37:28 -07:00
Sage Weil
467c525109 ceph: fix dn offset during readdir_prepopulate
When adding the readdir results to the cache, ceph_set_dentry_offset was
clobbered our just-set offset.  This can cause the readdir result offsets
to get out of sync with the server.  Add an argument to the helper so
that it does not.

This bug was introduced by 1cd3935bed.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-09-13 11:40:36 -07:00
Dan Carpenter
ac1f12ef56 ceph: ceph_get_inode() returns an ERR_PTR
ceph_get_inode() returns an ERR_PTR and it doesn't return a NULL.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2010-08-25 12:01:54 -07:00
Sage Weil
124514918b ceph: don't improperly set dir complete when holding EXCL cap
If we hold the EXCL cap, we cannot trust the dir stats from the MDS (num
files, subdirs) and must not incorrectly conclude that the directory is
empty.  If we do, we get can bad results from lookup (bad ENOENT) and
bad readdir results.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-08-22 21:33:32 -07:00
Sage Weil
2962507ca2 ceph: perform lazy reads when file mode and caps permit
If the file mode is marked as "lazy," perform cached/buffered reads when
the caps permit it.  Adjust the rdcache_gen and invalidation logic
accordingly so that we manage our cache based on the FILE_CACHE -or-
FILE_LAZYIO cap bits.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-08-01 20:11:39 -07:00
Yehuda Sadeh
03066f2345 ceph: use complete_all and wake_up_all
This fixes an issue triggered by running concurrent syncs. One of the syncs
would go through while the other would just hang indefinitely. In any case, we
never actually want to wake a single waiter, so the *_all functions should
be used.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
2010-07-27 13:11:17 -07:00
Sage Weil
8c696737aa ceph: fix leak of dentry in ceph_init_dentry() error path
If we fail to allocate a ceph_dentry_info, don't leak the dn reference.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-07-23 10:02:07 -07:00
Sage Weil
d69ed05a80 ceph: handle splice_dentry/d_materialize_unique error in readdir_prepopulate
Handle a splice_dentry failure (due to a d_materialize_unique error)
without crashing.  (Also, report the error code.)

Signed-off-by: Sage Weil <sage@newdream.net>
2010-06-21 16:04:10 -07:00
Henry C Chang
13a4214cd9 ceph: fix d_subdirs ordering problem
We misused list_move_tail() to order the dentry in d_subdirs.
This will screw up the d_subdirs order.

This bug can be reliably reproduced by:
1. mount ceph fs.
2. on ceph fs, git clone git://ceph.newdream.net/git/ceph.git
3. Run autogen.sh in ceph directory.
(Note: Errors only occur at the first time you run autogen.sh.)

Signed-off-by: Henry C Chang <henry_c_chang@tcloudcomputing.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2010-06-01 16:55:55 -07:00
Julia Lawall
7e34bc524e fs/ceph: Use ERR_CAST
Use ERR_CAST(x) rather than ERR_PTR(PTR_ERR(x)).  The former makes more
clear what is the purpose of the operation, which otherwise looks like a
no-op.

In the case of fs/ceph/inode.c, ERR_CAST is not needed, because the type of
the returned value is the same as the type of the enclosing function.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
type T;
T x;
identifier f;
@@

T f (...) { <+...
- ERR_PTR(PTR_ERR(x))
+ x
 ...+> }

@@
expression x;
@@

- ERR_PTR(PTR_ERR(x))
+ ERR_CAST(x)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-29 09:12:41 -07:00
Sage Weil
167c9e352d ceph: use common helper for aborted dir request invalidation
We invalidate I_COMPLETE and dentry leases in two places: on aborted mds
request and on request replay.  Use common helper to avoid duplicate code.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-17 15:25:40 -07:00
Sage Weil
1cd3935bed ceph: set dn offset when spliced
We want to assign an offset when the dentry goes from null to linked, which
is always done by splice_dentry().  Notably, we should NOT assign an
offset when a dentry is first created and is still null.

BUG if we try to splice a non-null dentry (we shouldn't).

Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-17 15:25:28 -07:00
Sage Weil
1b7facc41b ceph: don't clobber i_max_offset on already complete dir
This can screw up offsets assigned to new dentries and break dcache
readdir results.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-17 15:25:27 -07:00
Sage Weil
e8a7498715 ceph: skip set_dentry_offset work if directory not I_COMPLETE
Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-17 15:25:27 -07:00
Sage Weil
a6424e48c8 ceph: fix xattr dangling pointer / double free
If we use the xattr_blob, clear the pointer so we don't release the memory
at the bottom of the fuction.

Reported-by: Henry C Chang <henry_c_chang@tcloudcomputing.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-17 15:25:25 -07:00
Cheng Renquan
640ef79d27 ceph: use ceph_sb_to_client instead of ceph_client
ceph_sb_to_client and ceph_client are really identical, we need to dump
one; while function ceph_client is confusing with "struct ceph_client",
ceph_sb_to_client's definition is more clear; so we'd better switch all
call to ceph_sb_to_client.

  -static inline struct ceph_client *ceph_client(struct super_block *sb)
  -{
  -	return sb->s_fs_info;
  -}

Signed-off-by: Cheng Renquan <crquan@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-17 15:25:17 -07:00
Sage Weil
81a6cf2d30 ceph: invalidate affected dentry leases on aborted requests
If we abort a request, we return to caller, but the request may still
complete.  And if we hold the dir FILE_EXCL bit, we may not release a
lease when sending a request.  A simple un-tar, control-c, un-tar again
will reproduce the bug (manifested as a 'Cannot open: File exists').

Ensure we invalidate affected dentry leases (as well dir I_COMPLETE) so
we don't have valid (but incorrect) leases.  Do the same, consistently, at
other sites where I_COMPLETE is similarly cleared.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-17 10:25:45 -07:00
Sage Weil
04d000eb35 ceph: fix open file counting on snapped inodes when mds returns no caps
It's possible the MDS will not issue caps on a snapped inode, in which case
an open request may not __ceph_get_fmode(), botching the open file
counting.  (This is actually a server bug, but the client shouldn't BUG out
in this case.)

Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-11 09:53:55 -07:00
Sage Weil
c10f5e12ba ceph: clear dir complete on d_move
d_move() reorders the d_subdirs list, breaking the readdir result caching.
Unless/until d_move preserves that ordering, clear CEPH_I_COMPLETE on
rename.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-05-03 10:49:22 -07:00
Sage Weil
9358c6d4c0 ceph: fix dentry rehashing on virtual .snap dir
If a lookup fails on the magic .snap directory, we bind it to a magic
snap directory inode in ceph_lookup_finish().  That code assumes the dentry
is unhashed, but a recent server-side change started returning NULL leases
on lookup failure, causing the .snap dentry to be hashed and NULL by
ceph_fill_trace().

This causes dentry hash chain corruption, or a dies when d_rehash()
includes
	BUG_ON(!d_unhashed(entry));

So, avoid processing the NULL dentry lease if it the dentry matches the
snapdir name in ceph_fill_trace().  That allows the lookup completion to
properly bind it to the snapdir inode.  BUG there if dentry is hashed to
be sure.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-30 13:55:22 -07:00
Sage Weil
8b218b8a4a ceph: fix inode removal from snap realm when racing with migration
When an inode was dropped while being migrated between two MDSs,
i_cap_exporting_issued was non-zero such that issue caps were non-zero and
__ceph_is_any_caps(ci) was true.  This prevented the inode from being
removed from the snap realm, even as it was dropped from the cache.

Fix this by dropping any residual i_snap_realm ref in destroy_inode.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-03-20 21:33:08 -07:00
Yehuda Sadeh
c9af9fb68e ceph: don't truncate dirty pages in invalidate work thread
Instead of truncating the whole range of pages, we skip those
pages that are dirty or in the middle of writeback. Those pages
will be cleared later when the writeback completes.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
2010-02-19 14:40:51 -08:00
Sage Weil
2c27c9a57c ceph: fix typo in ceph_queue_writeback debug output
Signed-off-by: Sage Weil <sage@newdream.net>
2010-02-17 15:45:51 -08:00
Sage Weil
3c6f6b79a6 ceph: cleanup async writeback, truncation, invalidate helpers
Grab inode ref in helper.  Make work functions static, with consistent
naming.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-02-11 11:48:54 -08:00
Yehuda Sadeh
3d497d858a ceph: fix truncation when not holding caps
A truncation should occur when either we have the
specified caps for the file, or (in cases where we are
not the only ones referencing the file) when it is mapped
or when it is opened. The latter two cases were not
handled.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
2010-02-11 11:48:51 -08:00
Yehuda Sadeh
0f26c4b21b ceph: remove unreachable code
We never truncate to a smaller size without contacting the MDS.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
2010-01-29 12:42:39 -08:00
Sage Weil
5b1daecd59 ceph: properly handle aborted mds requests
Previously, if the MDS request was interrupted, we would unregister the
request and ignore any reply.  This could cause the caps or other cache
state to become out of sync.  (For instance, aborting dbench and doing
rm -r on clients would complain about a non-empty directory because the
client didn't realize it's aborted file create request completed.)

Even we don't unregister, we still can't process the reply normally because
we are no longer holding the caller's locks (like the dir i_mutex).

So, mark aborted operations with r_aborted, and in the reply handler, be
sure to process all the caps.  Do not process the namespace changes,
though, since we no longer will hold the dir i_mutex.  The dentry lease
state can also be ignored as it's more forgiving.

Signed-off-by: Sage Weil <sage@newdream.net>
2010-01-25 11:49:51 -08:00
Yehuda Sadeh
4baa75ef0e ceph: change dentry offset and position after splice_dentry
This fixes a bug, where we had the parent list have dentries with
offsets that are not monotonically increasing, which caused the ceph
dcache_readdir to skip entries.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Sage Weil <sage@newdream.net>
2010-01-14 12:23:14 -08:00
Sage Weil
c4a29f26d5 ceph: ensure rename target dentry fails revalidation
This works around a bug in vfs_rename_dir() that rehashes the target
dentry.  Ensure such dentries always fail revalidation by timing out the
dentry lease and kicking it out of the current directory lease gen.

This can be reverted when the vfs bug is fixed.

Signed-off-by: Sage Weil <sage@newdream.net>
2009-12-21 16:39:57 -08:00
Sage Weil
b6c1d5b81e ceph: simplify ceph_buffer interface
We never allocate the ceph_buffer and buffer separtely, so use a single
constructor.

Disallow put on NULL buffer; make the caller check.

Signed-off-by: Sage Weil <sage@newdream.net>
2009-12-07 12:17:17 -08:00
Sage Weil
b377ff13b3 ceph: initialize i_size/i_rbytes on snapdir
Signed-off-by: Sage Weil <sage@newdream.net>
2009-11-11 15:50:28 -08:00
Sage Weil
232d4b0131 ceph: move directory size logic to ceph_getattr
We can't fill i_size with rbytes at the fill_file_size stage without
adding additional checks for directories.  Notably, we want st_blocks
to remain 0 on directories so that 'du' still works.

Fill in i_blocks, i_size specially in ceph_getattr instead.

Signed-off-by: Sage Weil <sage@newdream.net>
2009-10-21 11:24:36 -07:00
Sage Weil
355da1eb7a ceph: inode operations
Inode cache and inode operations.  We also include routines to
incorporate metadata structures returned by the MDS into the client
cache, and some helpers to deal with file capabilities and metadata
leases.  The bulk of that work is done by fill_inode() and
fill_trace().

Signed-off-by: Sage Weil <sage@newdream.net>
2009-10-06 11:31:08 -07:00