The configfs operations ->make_item() and ->make_group() currently
return a new item/group.  A return of NULL signifies an error.  Because
of this, -ENOMEM is the only return code bubbled up the stack.

Multiple folks have requested the ability to return specific error codes
when these operations fail.  This patch adds that ability by changing the
->make_item/group() ops to return ERR_PTR() values.  These errors are
bubbled up appropriately.  NULL returns are changed to -ENOMEM for
compatibility.

Also updated are the in-kernel users of configfs.

This is a rework of reverted commit 11c3b792.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

This reverts commit 11c3b792.  The code
will move to PTR_ERR().
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

This patch fixes a mmap_truncate bug which was found by ocfs2 test suite.

In an ocfs2 cluster more than 1 node, run program mmap_truncate, which races
mmap writes and truncates from multiple processes. While the test is
running, a stat from another node forces writeout, causing an oops in
ocfs2_get_block() because it sees a buffer to write which isn't allocated.

This patch fixed the bug by clear dirty and uptodate bits in buffer, leave
the buffer unmapped and return.

Fix is suggested by Mark Fasheh, and I code up the patch.
Signed-off-by: NColy Li <coyli@suse.de>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

Fix fs/compat_ioctl.c to handle CONFIG_BLOCK=n, CONFIG_SCSI=n to avoid
build errors:

In file included from include/scsi/scsi.h:12,
                 from fs/compat_ioctl.c:71:
include/scsi/scsi_cmnd.h:27:25: warning: "BLK_MAX_CDB" is not defined
include/scsi/scsi_cmnd.h:28:3: error: #error MAX_COMMAND_SIZE can not be bigger than BLK_MAX_CDB
In file included from include/scsi/scsi.h:12,
                 from fs/compat_ioctl.c:71:
include/scsi/scsi_cmnd.h: In function 'scsi_bidi_cmnd':
include/scsi/scsi_cmnd.h:182: error: implicit declaration of function 'blk_bidi_rq'
include/scsi/scsi_cmnd.h:183: error: dereferencing pointer to incomplete type
include/scsi/scsi_cmnd.h: In function 'scsi_in':
include/scsi/scsi_cmnd.h:189: error: dereferencing pointer to incomplete type
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Push it into those callback functions that actually need it.

Note that all the NFS operations use their own locking, so don't need the
BKL. Ditto for the rpcbind client.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Page accesses are serialised using the page locks, whereas all attribute
updates are serialised using the inode->i_lock.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Page cache accesses are serialised using page locks, whereas attribute
updates are serialised using inode->i_lock.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Attribute updates are safe, and dentry operations are protected using VFS
level locks. Defer removing the BKL from sillyrename until a separate
patch.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

All dentry-related operations are already BKL-safe, since they are
protected by the VFS locking. No extra locks should be needed in the NFS
code.

In the case of nfs_revalidate_inode(), we're only doing an attribute
update (protected by the inode->i_lock).
In the case of nfs_lookup(), we're instantiating a new dentry, so there
should be no contention possible until after we call d_materialise_unique.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

nfs_instantiate() does not require the BKL, neither do the attribute
updates or the RPC code.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

All the NFSv4 stateful operations are already protected by other locks (in
particular by the rpc_sequence locks.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The main problem is dealing with inode->i_size: we need to set the
inode->i_lock on all attribute updates, and so vmtruncate won't cut it.
Make an NFS-private version of vmtruncate that has the necessary locking
semantics.

The result should be that the following inode attribute updates are
protected by inode->i_lock
	nfsi->cache_validity
	nfsi->read_cache_jiffies
	nfsi->attrtimeo
	nfsi->attrtimeo_timestamp
	nfsi->change_attr
	nfsi->last_updated
	nfsi->cache_change_attribute
	nfsi->access_cache
	nfsi->access_cache_entry_lru
	nfsi->access_cache_inode_lru
	nfsi->acl_access
	nfsi->acl_default
	nfsi->nfs_page_tree
	nfsi->ncommit
	nfsi->npages
	nfsi->open_files
	nfsi->silly_list
	nfsi->acl
	nfsi->open_states
	inode->i_size
	inode->i_atime
	inode->i_mtime
	inode->i_ctime
	inode->i_nlink
	inode->i_uid
	inode->i_gid

The following is protected by dir->i_mutex
	nfsi->cookieverf
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

fcntl(F_GETLK) on an nfs client incorrectly returns
the values for the conflicting lock. fl_len value is
always 1.
If the conflicting lock is (0, 4095) the F_GETLK
request for (1024, 10) returns (0, 1), which doesn't
even cover the requested range, and is quite confusing.
The fix is trivial, set fl_end from the fl_end value
recieved from the nfs server.
Signed-off-by: NFelix Blyakher <felixb@sgi.com>
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Add UBIFS to Makefile and Kbuild.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: NAdrian Hunter <ext-adrian.hunter@nokia.com>

This is a new flash file system. See
http://www.linux-mtd.infradead.org/doc/ubifs.htmlSigned-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: NAdrian Hunter <ext-adrian.hunter@nokia.com>

When allow_link() succeeds but create_link() fails, the subsystem is not
informed of the failure.

This patch fixes this by calling drop_link() on create_link() failures.
Signed-off-by: NLouis Rilling <Louis.Rilling@kerlabs.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

The configfs operations ->make_item() and ->make_group() currently
return a new item/group.  A return of NULL signifies an error.  Because
of this, -ENOMEM is the only return code bubbled up the stack.

Multiple folks have requested the ability to return specific error codes
when these operations fail.  This patch adds that ability by changing the
->make_item/group() ops to return an int.

Also updated are the in-kernel users of configfs.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

When fixing the rename() vs rmdir() deadlock, we stopped locking default groups'
inodes in configfs_detach_prep(), letting racing mkdir() in default groups
proceed concurrently. This enables races like below happen, which leads to a
failing mkdir() making rmdir() fail, despite the group to remove having no
user-created directory under it in the end.

	process A: 			process B:
	/* PWD=A/B */
	mkdir("C")
	  make_item("C")
	  attach_group("C")
					rmdir("A")
					  detach_prep("A")
					    detach_prep("B")
					      error because of "C"
					  return -ENOTEMPTY
	    attach_group("C/D")
	      error (eg -ENOMEM)
	  return -ENOMEM

This patch prevents such scenarii by making rmdir() wait as long as
detach_prep() fails because a racing mkdir() is in the middle of attach_group().
To achieve this, mkdir() sets a flag CONFIGFS_USET_IN_MKDIR in parent's
configfs_dirent before calling attach_group(), and clears the flag once
attach_group() is done. detach_prep() fails with -EAGAIN whenever the flag is
hit and returns the guilty inode's mutex so that rmdir() can wait on it.
Signed-off-by: NLouis Rilling <Louis.Rilling@kerlabs.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

This patch fixes the deadlock between racing sys_rename() and configfs_rmdir().

The idea is to avoid locking i_mutexes of default groups in
configfs_detach_prep(), and rely instead on the new configfs_dirent_lock to
protect against configfs_dirent's linkage mutations. To ensure that an mkdir()
racing with rmdir() will not create new items in a to-be-removed default group,
we make configfs_new_dirent() check for the CONFIGFS_USET_DROPPING flag right
before linking the new dirent, and return error if the flag is set. This makes
racing mkdir()/symlink()/dir_open() fail in places where errors could already
happen, resp. in (attach_item()|attach_group())/create_link()/new_dirent().

configfs_depend() remains safe since it locks all the path from configfs root,
and is thus mutually exclusive with rmdir().

An advantage of this is that now detach_groups() unconditionnaly takes the
default groups i_mutex, which makes it more consistent with populate_groups().
Signed-off-by: NLouis Rilling <Louis.Rilling@kerlabs.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

This patch makes configfs_new_dirent return negative error code instead of NULL,
which will be useful in the next patch to differentiate ENOMEM from ENOENT.
Signed-off-by: NLouis Rilling <Louis.Rilling@kerlabs.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Symlinks to a config_item are listed under its configfs_dirent s_links, but the
list mutations are not protected by any common lock.

This patch uses the configfs_dirent_lock spinlock to add the necessary
protection.

Note: we should also protect the list_empty() test in configfs_detach_prep() but
1/ the lock should not be released immediately because nothing would prevent the
list from being filled after a successful list_empty() test, making the problem
tricky,
2/ this will be solved by the rmdir() vs rename() deadlock bugfix.
Signed-off-by: NLouis Rilling <Louis.Rilling@kerlabs.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

This patch introduces configfs_dirent_lock spinlock to protect configfs_dirent
traversals against linkage mutations (add/del/move). This will allow
configfs_detach_prep() to avoid locking i_mutexes.

Locking rules for configfs_dirent linkage mutations are the same plus the
requirement of taking configfs_dirent_lock. For configfs_dirent walking, one can
either take appropriate i_mutex as before, or take configfs_dirent_lock.

The spinlock could actually be a mutex, but the critical sections are either
O(1) or should not be too long (default groups walking in last patch).

ChangeLog:
  - Clarify the comment on configfs_dirent_lock usage
  - Move sd->s_element init before linking the new dirent
  - In lseek(), do not release configfs_dirent_lock before the dirent is
    relinked.
Signed-off-by: NLouis Rilling <Louis.Rilling@kerlabs.com>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

Some system files are per-slot.  Their names include the slot number.
ocfs2_sprintf_system_inode_name() uses the system inode definitions to
fill in the slot number with snprintf().

For global system files, there is no node number, and the name was
printed as a format with no arguments.  -Wformat-nonliteral and
-Wformat-security don't like this.  Instead, use a static "%s" format
and the name as the argument.
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

A couple places use OCFS2_DEBUG_FS where they really mean
CONFIG_OCFS2_DEBUG_FS.
Reported-by: NRobert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: NJoel Becker <joel.becker@oracle.com>

suseconds_t is type long on most arches except sparc64 where it is type int.
This patch silences the following warnings that are generated when building
on it.

netdebug.c: In function 'nst_seq_show':
netdebug.c:152: warning: format '%lu' expects type 'long unsigned int', but argument 13 has type 'suseconds_t'
netdebug.c:152: warning: format '%lu' expects type 'long unsigned int', but argument 15 has type 'suseconds_t'
netdebug.c:152: warning: format '%lu' expects type 'long unsigned int', but argument 17 has type 'suseconds_t'
netdebug.c: In function 'sc_seq_show':
netdebug.c:332: warning: format '%lu' expects type 'long unsigned int', but argument 19 has type 'suseconds_t'
netdebug.c:332: warning: format '%lu' expects type 'long unsigned int', but argument 21 has type 'suseconds_t'
netdebug.c:332: warning: format '%lu' expects type 'long unsigned int', but argument 23 has type 'suseconds_t'
netdebug.c:332: warning: format '%lu' expects type 'long unsigned int', but argument 25 has type 'suseconds_t'
netdebug.c:332: warning: format '%lu' expects type 'long unsigned int', but argument 27 has type 'suseconds_t'
netdebug.c:332: warning: format '%lu' expects type 'long unsigned int', but argument 29 has type 'suseconds_t'
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch ensures the mount fails if the fs is unable to load the journal.
Signed-off-by: NWengang Wang <wen.gang.wang@oracle.com>
Acked-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch silences an EINVAL error message in ocfs2_file_aio_read()
that is always due to a user error.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Acked-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

Fix printk format warnings when OCFS2_FS_STATS=n:

linux-next-20080528/fs/ocfs2/dlmglue.c: In function 'ocfs2_dlm_seq_show':
linux-next-20080528/fs/ocfs2/dlmglue.c:2623: warning: format '%llu' expects type 'long long unsigned int', but argument 3 has type 'int'
linux-next-20080528/fs/ocfs2/dlmglue.c:2623: warning: format '%llu' expects type 'long long unsigned int', but argument 4 has type 'int'
linux-next-20080528/fs/ocfs2/dlmglue.c:2623: warning: format '%llu' expects type 'long long unsigned int', but argument 7 has type 'int'
linux-next-20080528/fs/ocfs2/dlmglue.c:2623: warning: format '%llu' expects type 'long long unsigned int', but argument 8 has type 'int'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch adds code to track the number of times the fs takes
various cluster locks as well as the times associated with it.
The information is made available to users via debugfs.

This patch was originally written by Jan Kara <jack@suse.cz>.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch adds config option CONFIG_OCFS2_FS_STATS to allow building
the fs with instrumentation enabled. An upcoming patch will provide
support to instrument cluster locking, which is a crucial overhead in
a cluster file system. This config option allows users to avoid the cpu
and memory overhead that is involved in gathering such statistics.
Signed-off-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

This patch exports the 'sync_sb_inodes()' which is needed for
UBIFS because it has to force write-back from time to time.
Namely, the UBIFS budgeting subsystem forces write-back when
its pessimistic callculations show that there is no free
space on the media.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

This patch makes 'sync_sb_inodes()' lock 'inode_lock', rather
than expect that the caller will do this.

This change was previously done by Hans Reiser <reiser@namesys.com>
and sat in the -mm tree.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>