Commit 1a747ee0 ("locks: don't call ->copy_lock methods on return of
conflicting locks") changed fs/lockd/svclock.c to call
__locks_copy_lock() instead of locks_copy_lock(), but lockd can be built
as a module and __locks_copy_lock() is not exported, which causes a
build error
ERROR: "__locks_copy_lock" [fs/lockd/lockd.ko] undefined!
with CONFIG_LOCKD=m.
Fix this by exporting __locks_copy_lock().
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.infradead.org/mtd-2.6: (82 commits)
[MTD] m25p80: Add Support for ATMEL AT25DF641 64-Megabit SPI Flash
[MTD] m25p80: add FAST_READ access support to M25Pxx
[MTD] [NAND] bf5xx_nand: Avoid crash if bfin_mac is installed.
[MTD] [NAND] at91_nand: control NCE signal
[MTD] [NAND] AT91 hardware ECC compile fix for at91sam9263 / at91sam9260
[MTD] [NAND] Hardware ECC controller on at91sam9263 / at91sam9260
[JFFS2] Introduce dbg_readinode2 log level, use it to shut read_dnode() up
[JFFS2] Fix jffs2_reserve_space() when all blocks are pending erasure.
[JFFS2] Add erase_checking_list to hold blocks being marked.
UBI: add a message
[JFFS2] Return values of jffs2_block_check_erase error paths
[MTD] Clean up AR7 partition map support
[MTD] [NOR] Fix Intel CFI driver for collie flash
[JFFS2] Finally remove redundant ref->__totlen field.
[JFFS2] Honour TEST_TOTLEN macro in debugging code. ref->__totlen is going!
[JFFS2] Add paranoia debugging for superblock counts
[JFFS2] Fix free space leak with in-band cleanmarkers
[JFFS2] Self-sufficient #includes in jffs2_fs_i.h: include <linux/mutex.h>
[MTD] [NAND] Verify probe by retrying to checking the results match
[MTD] [NAND] S3C2410 Allow ECC disable to be specified by the board
...
Presumably this is left over from earlier drafts of v4, which listed
TIME_METADATA as writeable. It's read-only in rfc 3530, and shouldn't
be modifiable anyway.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The file_lock structure is used both as a heavy-weight representation of
an active lock, with pointers to reference-counted structures, etc., and
as a simple container for parameters that describe a file lock.
The conflicting lock returned from __posix_lock_file is an example of
the latter; so don't call the filesystem or lock manager callbacks when
copying to it. This also saves the need for an unnecessary
locks_init_lock in the nfsv4 server.
Thanks to Trond for pointing out the error.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Add /proc/fs/nfsd/unlock_filesystem, which allows e.g.:
shell> echo /mnt/sfs1 > /proc/fs/nfsd/unlock_filesystem
so that a filesystem can be unmounted before allowing a peer nfsd to
take over nfs service for the filesystem.
Signed-off-by: S. Wendy Cheng <wcheng@redhat.com>
Cc: Lon Hohberger <lhh@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
fs/lockd/svcsubs.c | 66 +++++++++++++++++++++++++++++++++++++++-----
fs/nfsd/nfsctl.c | 65 +++++++++++++++++++++++++++++++++++++++++++
include/linux/lockd/lockd.h | 7 ++++
3 files changed, 131 insertions(+), 7 deletions(-)
For high-availability NFS service, we generally need to be able to drop
file locks held on the exported filesystem before moving clients to a
new server. Currently the only way to do that is by shutting down lockd
entirely, which is often undesireable (for example, if you want to
continue exporting other filesystems).
This patch allows the administrator to release all locks held by clients
accessing the client through a given server ip address, by echoing that
address to a new file, /proc/fs/nfsd/unlock_ip, as in:
shell> echo 10.1.1.2 > /proc/fs/nfsd/unlock_ip
The expected sequence of events can be:
1. Tear down the IP address
2. Unexport the path
3. Write IP to /proc/fs/nfsd/unlock_ip to unlock files
4. Signal peer to begin take-over.
For now we only support IPv4 addresses and NFSv2/v3 (NFSv4 locks are not
affected).
Also, if unmounting the filesystem is required, we assume at step 3 that
clients using the given server ip are the only clients holding locks on
the given filesystem; otherwise, an additional patch is required to
allow revoking all locks held by lockd on a given filesystem.
Signed-off-by: S. Wendy Cheng <wcheng@redhat.com>
Cc: Lon Hohberger <lhh@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
fs/lockd/svcsubs.c | 66 +++++++++++++++++++++++++++++++++++++++-----
fs/nfsd/nfsctl.c | 65 +++++++++++++++++++++++++++++++++++++++++++
include/linux/lockd/lockd.h | 7 ++++
3 files changed, 131 insertions(+), 7 deletions(-)
fcntl_setlease() has a struct dentry* that is used only once; this patch
removes it.
Signed-off-by: David M. Richter <richterd@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
In generic_setlease(), the struct file_lock is allocated after tests for the
presence of conflicting readers/writers is done, despite the fact that the
allocation might block; this patch moves the allocation earlier. A subsequent
set of patches will rely on this behavior to properly serialize between a
modified __break_lease() and generic_setlease().
Signed-off-by: David M. Richter <richterd@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
In generic_setlease(), we don't need to allocate a new struct file_lock
or check for readers or writers when called with F_UNLCK.
Signed-off-by: David M. Richter <richterd@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Fixes a return-value mixup from 85c59580b3
"locks: Fix potential OOPS in generic_setlease()", in which -ENOMEM replaced
what had been intended to stay -EAGAIN in the variable "error".
Signed-off-by: David M. Richter <richterd@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* 'file' argument is unused; lose it.
* move setting flags from the caller (dupfd()) to locate_fd();
pass cloexec flag as new argument. Note that files_fdtable()
that used to be in dupfd() isn't needed in the place in
locate_fd() where the moved code ends up - we know that ->file_lock
hadn't been dropped since the last time we calculated fdt because
we can get there only if expand_files() returns 0 and it doesn't
drop/reacquire in that case.
* move getting/dropping ->file_lock into locate_fd(). Now the caller
doesn't need to do anything with files_struct *files anymore and
we can move that inside locate_fd() as well, killing the
struct files_struct * argument.
At that point locate_fd() is extremely similar to get_unused_fd_flags()
and the next patches will merge those two.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* let unshare_files() give caller the displaced files_struct
* don't bother with grabbing reference only to drop it in the
caller if it hadn't been shared in the first place
* in that form unshare_files() is trivially implemented via
unshare_fd(), so we eliminate the duplicate logics in fork.c
* reset_files_struct() is not just only called for current;
it will break the system if somebody ever calls it for anything
else (we can't modify ->files of somebody else). Lose the
task_struct * argument.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* unshare_files() can fail; doing it after irreversible actions is wrong
and de_thread() is certainly irreversible.
* since we do it unconditionally anyway, we might as well do it in do_execve()
and save ourselves the PITA in binfmt handlers, etc.
* while we are at it, binfmt_som actually leaked files_struct on failure.
As a side benefit, unshare_files(), put_files_struct() and reset_files_struct()
become unexported.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
[CIFS] Fix typo in previous commit
[CIFS] Fix define for new proxy cap to match documentation
[CIFS] Fix UNC path prefix on QueryUnixPathInfo to have correct slash
[CIFS] Reserve new proxy cap for WAFS
[CIFS] Add various missing flags and defintions
[CIFS] make cifs_dfs_automount_list_static
[CIFS] Fix oops when slow oplock process races with unmount
[CIFS] Fix acl length when very short ACL being modified by chmod
[CIFS] Fix looping on reconnect to Samba when unexpected tree connect fail on reconnect
[CIFS] minor update to change log
* git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (80 commits)
SUNRPC: Invalidate the RPCSEC_GSS session if the server dropped the request
make nfs_automount_list static
NFS: remove duplicate flags assignment from nfs_validate_mount_data
NFS - fix potential NULL pointer dereference v2
SUNRPC: Don't change the RPCSEC_GSS context on a credential that is in use
SUNRPC: Fix a race in gss_refresh_upcall()
SUNRPC: Don't disconnect more than once if retransmitting NFSv4 requests
SUNRPC: Remove the unused export of xprt_force_disconnect
SUNRPC: remove XS_SENDMSG_RETRY
SUNRPC: Protect creds against early garbage collection
NFSv4: Attempt to use machine credentials in SETCLIENTID calls
NFSv4: Reintroduce machine creds
NFSv4: Don't use cred->cr_ops->cr_name in nfs4_proc_setclientid()
nfs: fix printout of multiword bitfields
nfs: return negative error value from nfs{,4}_stat_to_errno
NLM/lockd: Ensure client locking calls use correct credentials
NFS: Remove the buggy lock-if-signalled case from do_setlk()
NLM/lockd: Fix a race when cancelling a blocking lock
NLM/lockd: Ensure that nlmclnt_cancel() returns results of the CANCEL call
NLM: Remove the signal masking in nlmclnt_proc/nlmclnt_cancel
...
The transport encryption capability and new SetFSInfo level were missing, and the
new proxy capability (which Samba server is implementing) and proxy setfsinfo needed
to be moved down to not collide with Samba's transport encryption capability.
CC: Jeremy Allison <jra@samba.org>
CC: Sam Liddicott <sam@lidicott.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Currently, knfsd only clears the setuid bit if the owner of a file is
changed on a SETATTR call, and only clears the setgid bit if the group
is changed. POSIX says this in the spec for chown():
"If the specified file is a regular file, one or more of the
S_IXUSR, S_IXGRP, or S_IXOTH bits of the file mode are set, and the
process does not have appropriate privileges, the set-user-ID
(S_ISUID) and set-group-ID (S_ISGID) bits of the file mode shall
be cleared upon successful return from chown()."
If I'm reading this correctly, then knfsd is doing this wrong. It should
be clearing both the setuid and setgid bit on any SETATTR that changes
the uid or gid. This wasn't really as noticable before, but now that the
ATTR_KILL_S*ID bits are a no-op for the NFS client, it's more evident.
This patch corrects the nfsd_setattr logic so that this occurs. It also
does a bit of cleanup to the function.
There is also one small behavioral change. If a SETATTR call comes in
that changes the uid/gid and the mode, then we now only clear the setgid
bit if the group execute bit isn't set. The setgid bit without a group
execute bit signifies mandatory locking and we likely don't want to
clear the bit in that case. Since there is no call in POSIX that should
generate a SETATTR call like this, then this should rarely happen, but
it's worth noting.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
When svc_recv returns an unexpected error, lockd will print a warning
and exit. This problematic for several reasons. In particular, it will
cause the reference counts for the thread to be wrong, and can lead to a
potential BUG() call.
Rather than exiting on error from svc_recv, have the thread do a 1s
sleep and then retry the loop. This is unlikely to cause any harm, and
if the error turns out to be something temporary then it may be able to
recover.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
When svc_recv returns an unexpected error, nfs_callback_svc will print a
warning and exit. This problematic for several reasons. In particular,
it will cause the reference counts for the thread to be wrong, and no
new thread will be started until all nfs4 mounts are unmounted.
Rather than exiting on error from svc_recv, have the thread do a 1s
sleep and then retry the loop. This is unlikely to cause any harm, and
if the error turns out to be something temporary then it may be able to
recover.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
There's no need to dynamically allocate this memory, and doing so may
create the possibility of races on shutdown of the rpc client. (We've
witnessed it only after adding rpcsec_gss support to the server, after
which the rpc code can send destroys calls that expect to still be able
to access the rpc_stats structure after it has been destroyed.)
Such races are in theory possible if the module containing this "static"
memory is removed very quickly after an rpc client is destroyed, but
we haven't seen that happen.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
As of 5996a298da ("NLM: don't unlock on
cancel requests") we no longer unlock in this case, so the comment is no
longer accurate.
Thanks to Stuart Friedberg for pointing out the inconsistency.
Cc: Stuart Friedberg <sfriedberg@hp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: Because NFSD_V4 "depends on" NFSD_V3, it appears as a child of
the NFSD_V3 menu entry, and is not visible if NFSD_V3 is unselected.
Replace the dependency on NFSD_V3 with a "select NFSD_V3". This makes
NFSD_V4 look and work just like NFS_V3, while ensuring that NFSD_V3 is
enabled if NFSD_V4 is.
Sam Ravnborg adds:
"This use of select is questionable. In general it is bad to select
a symbol with dependencies.
In this case the dependencies of NFSD_V3 are duplicated for NFSD_V4
so we will not se erratic configurations but do you remember to
update NFSD_V4 when you add a depends on NFSD_V3?
But I see no other clean way to do it right now."
Later he said:
"My comment was more to say we have things to address in kconfig.
This is abuse in the acceptable range."
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Recently, commit 440bcc59 added a reverse dependency to fs/Kconfig to
ensure that PROC_FS was enabled if SUNRPC_GSS was enabled.
Apparently this isn't necessary because the auth_gss components under
net/sunrpc will build correctly even if PROC_FS is disabled, though
RPCSEC_GSS will not work without /proc.
It also violates the guideline in Documentation/kbuild/kconfig-language.txt
that states "In general use select only for non-visible symbols (no prompts
anywhere) and for symbols with no dependencies."
To address these issues, remove the dependency.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Recently, commit 440bcc59 added a reverse dependency to fs/Kconfig to
ensure that PROC_FS was enabled if NFSD_V4 was enabled.
There is a guideline in Documentation/kbuild/kconfig-language.txt that
states "In general use select only for non-visible symbols (no prompts
anywhere) and for symbols with no dependencies."
A quick grep around other Kconfig files reveals that no entry currently
uses "select PROC_FS" -- every one uses "depends on". Thus CONFIG_NFSD_V4
should use "depends on PROC_FS" as well.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Move the code that actually parses the filehandle and looks up the
dentry and export to a separate function. This simplifies the reference
counting a little and moves fh_verify() a little closer to the kernel
ideal of small, minimally-indentended functions. Clean up a few other
minor style sins along the way.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Neil Brown <neilb@suse.de>
While lease is correctly checked by supplying the type argument to
vfs_setlease(), it's stored with fl_type uninitialized. This breaks the
logic when checking the type of the lease. The fix is to initialize
fl_type.
The old code still happened to function correctly since F_RDLCK is zero,
and we only implement read delegations currently (nor write
delegations). But that's no excuse for not fixing this.
Signed-off-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
There's a general push to convert kernel threads to use the (much
cleaner) kthread API. This patch converts the NFSv4 callback kernel
thread to the kthread API. In addition to being generally cleaner this
also removes the dependency on signals when shutting down the thread.
Note that this patch depends on the recent patches to svc_recv() to
make it check kthread_should_stop() periodically. Those patches are
in Bruce's tree at the moment and are slated for 2.6.26 along with
the lockd conversion, so this conversion is probably also appropriate
for 2.6.26.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
fs/nfsd/vfs.c:991:27: warning: Using plain integer as NULL pointer
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Add extern to nfsd/nfsd.h
fs/nfsd/nfssvc.c:146:5: warning: symbol 'nfsd_nrthreads' was not declared. Should it be static?
fs/nfsd/nfssvc.c:261:5: warning: symbol 'nfsd_nrpools' was not declared. Should it be static?
fs/nfsd/nfssvc.c:269:5: warning: symbol 'nfsd_get_nrthreads' was not declared. Should it be static?
fs/nfsd/nfssvc.c:281:5: warning: symbol 'nfsd_set_nrthreads' was not declared. Should it be static?
fs/nfsd/export.c:1534:23: warning: symbol 'nfs_exports_op' was not declared. Should it be static?
Add include of auth.h
fs/nfsd/auth.c:27:5: warning: symbol 'nfsd_setuser' was not declared. Should it be static?
Make static, move forward declaration closer to where it's needed.
fs/nfsd/nfs4state.c:1877:1: warning: symbol 'laundromat_main' was not declared. Should it be static?
Make static, forward declaration was already marked static.
fs/nfsd/nfs4idmap.c:206:1: warning: symbol 'idtoname_parse' was not declared. Should it be static?
fs/nfsd/vfs.c:1156:1: warning: symbol 'nfsd_create_setattr' was not declared. Should it be static?
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
There's no reason for a mutex here, except to allow an allocation under
the lock, which we can avoid with the usual trick of preallocating
memory for the new object and freeing it if it turns out to be
unnecessary.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Use list_for_each_entry(). Also, in keeping with kernel style, make the
normal case (kzalloc succeeds) unindented and handle the abnormal case
with a goto.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The sm_count is decremented to zero but left on the nsm_handles list.
So in the space between decrementing sm_count and acquiring nsm_mutex,
it is possible for another task to find this nsm_handle, increment the
use count and then enter nsm_release itself.
Thus there's nothing to prevent the nsm being freed before we acquire
nsm_mutex here.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
fs/lockd/svcshare.c:74:50: warning: Using plain integer as NULL pointer
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This patch makes the needlessly global nfsd_create_setattr() static.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
As far as I can tell, selecting the CRYPTO and CRYPTO_MD5 entries under
CONFIG_NFSD is redundant, since CONFIG_NFSD_V4 already selects
RPCSEC_GSS_KRB5, which selects these entries.
Testing with "make menuconfig" shows that the entries under CRYPTO still
properly reflect "Y" or "M" based on the setting of CONFIG_NFSD after this
change is applied.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: since NFSD_V2_ACL is a boolean, it can be selected safely
under the NFSD_V3_ACL entry (also a boolean).
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: since FS_POSIX_ACL is a non-visible boolean entry, it can be
selected safely under the NFSD_V4 entry (also a boolean).
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: refresh the help text for Kconfig items related to the NFS
server. Remove obsolete URLs, and make the language consistent among
the options.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Likewise, distros usually leave CONFIG_NFSD_TCP enabled.
TCP support in the Linux NFS server is stable enough that we can leave it
on always. CONFIG_NFSD_TCP adds about 10 lines of code, and defaults to
"Y" anyway.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The code here is difficult to understand; attempt to clarify somewhat by
pulling out one of the more mystifying conditionals into a separate
function.
While we're here, also add lease_time to the list of attributes that we
don't really need to cross a mountpoint to fetch.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Peter Staubach <staubach@redhat.com>
Thanks to Robert Day for pointing out that these two defines are unused.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Trond Myklebust <trond@netapp.com>Trond Myklebust <trond@netapp.com>
Cc: Neil Brown <neilb@suse.de>
Cc: "Robert P. J. Day" <rpjday@crashcourse.ca>
This adds IPv6 support to the interfaces that are used to express nfsd
exports. All addressed are stored internally as IPv6; backwards
compatibility is maintained using mapped addresses.
Thanks to Bruce Fields, Brian Haley, Neil Brown and Hideaki Joshifuji
for comments
Signed-off-by: Aurelien Charbon <aurelien.charbon@bull.net>
Cc: Neil Brown <neilb@suse.de>
Cc: Brian Haley <brian.haley@hp.com>
Cc: YOSHIFUJI Hideaki / 吉藤英明 <yoshfuji@linux-ipv6.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Have lockd_up start lockd using kthread_run. With this change,
lockd_down now blocks until lockd actually exits, so there's no longer
need for the waitqueue code at the end of lockd_down. This also means
that only one lockd can be running at a time which simplifies the code
within lockd's main loop.
This also adds a check for kthread_should_stop in the main loop of
nlmsvc_retry_blocked and after that function returns. There's no sense
continuing to retry blocks if lockd is coming down anyway.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Lockd caches information about hosts that have recently held locks to
expedite the taking of further locks.
It periodically discards this information for hosts that have not been
used for a few minutes.
lockd currently has a value NLM_HOST_MAX, and changes the 'garbage
collection' behaviour when the number of hosts exceeds this threshold.
However its behaviour is strange, and likely not what was intended.
When the number of hosts exceeds the max, it scans *less* often (every
2 minutes vs every minute) and allows unused host information to
remain around longer (5 minutes instead of 2).
Having this limit is of dubious value anyway, and we have not
suffered from the code not getting the limit right, so remove the
limit altogether. We go with the larger values (discard 5 minute old
hosts every 2 minutes) as they are probably safer.
Maybe the periodic garbage collection should be replace to with
'shrinker' handler so we just respond to memory pressure....
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
We haven't seen bugs in this for a while now, since the rewrite. No need
to be _quite_ so verbose...
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
When _all_ the blocks were on the erase_pending_list, we could't find a
block to GC from but there was no _actually_ free space, and
jffs2_reserve_space() would get a little unhappy.
Handle this case by returning -EAGAIN from jffs2_garbage_collect_pass().
There are two callers of that function -- jffs2_flush_wbuf_gc(), which
will interpret it as an error and flush the writebuffer by other means,
and jffs2_reserve_space(), which we modify to respond to -EAGAIN with an
immediate call to jffs2_erase_pending_blocks() and another run round the
loop.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Just to keep the debug code happy when it's adding all the blocks up.
Otherwise, they disappear for a while while the locks are dropped to
check them and write the cleanmarker.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
It looks the error paths in jffs2_block_check_erase() have wrong return
values. A block that failed to be erased never gets marked as bad.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Show peer group ID of nearest dominating group that has intersection
with the mount's namespace.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[mszeredi@suse.cz] rewrite and split big patch into managable chunks
/proc/mounts in its current form lacks important information:
- propagation state
- root of mount for bind mounts
- the st_dev value used within the filesystem
- identifier for each mount and it's parent
It also suffers from the following problems:
- not easily extendable
- ambiguity of mountpoints within a chrooted environment
- doesn't distinguish between filesystem dependent and independent options
- doesn't distinguish between per mount and per super block options
This patch introduces /proc/<pid>/mountinfo which attempts to address
all these deficiencies.
Code shared between /proc/<pid>/mounts and /proc/<pid>/mountinfo is
extracted into separate functions.
Thanks to Al Viro for the help in getting the design right.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Allow /proc/<pid>/mountinfo to use the root of <pid> to calculate
mountpoints.
- move definition of 'struct proc_mounts' to <linux/mnt_namespace.h>
- add the process's namespace and root to this structure
- pass a pointer to 'struct proc_mounts' into seq_operations
In addition the following cleanups are made:
- use a common open function for /proc/<pid>/{mounts,mountstat}
- surround namespace.c part of these proc files with #ifdef CONFIG_PROC_FS
- make the seq_operations structures const
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Add a unique ID to each peer group using the IDR infrastructure. The
identifiers are reused after the peer group dissolves.
The IDR structures are protected by holding namepspace_sem for write
while allocating or deallocating IDs.
IDs are allocated when a previously unshared vfsmount becomes the
first member of a peer group. When a new member is added to an
existing group, the ID is copied from one of the old members.
IDs are freed when the last member of a peer group is unshared.
Setting the MNT_SHARED flag on members of a subtree is done as a
separate step, after all the IDs have been allocated. This way an
allocation failure can be cleaned up easilty, without affecting the
propagation state.
Based on design sketch by Al Viro.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Add a unique ID to each vfsmount using the IDR infrastructure. The
identifiers are reused after the vfsmount is freed.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Add a new function:
seq_file_root()
This is similar to seq_path(), but calculates the path relative to the
given root, instead of current->fs->root. If the path was unreachable
from root, then modify the root parameter to reflect this.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[mszeredi@suse.cz] split big patch into managable chunks
Add the following functions:
dentry_path()
seq_dentry()
These are similar to d_path() and seq_path(). But instead of
calculating the path within a mount namespace, they calculate the path
from the root of the filesystem to a given dentry, ignoring mounts
completely.
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
[PATCH] get rid of __exit_files(), __exit_fs() and __put_fs_struct()
[PATCH] proc_readfd_common() race fix
[PATCH] double-free of inode on alloc_file() failure exit in create_write_pipe()
[PATCH] teach seq_file to discard entries
[PATCH] umount_tree() will unhash everything itself
[PATCH] get rid of more nameidata passing in namespace.c
[PATCH] switch a bunch of LSM hooks from nameidata to path
[PATCH] lock exclusively in collect_mounts() and drop_collected_mounts()
[PATCH] move a bunch of declarations to fs/internal.h
Haven't had any complaints about it recently, despite having the test
code enabled to verify that the calculated length is correct.
Kill it off, just by #undef TEST_TOTLEN for now; removing it for real
can come a little later.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
The problem fixed in commit 014b164e13
(space leak with in-band cleanmarkers) would have been caught a lot
quicker if our paranoid debugging mode had included adding up the size
counts from all the eraseblocks and comparing the totals with the counts
in the superblock. Add that.
Make jffs2_mark_erased_block() file the newly-erased block on the
free_list before calling the debug function, to make it happy.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Since we drop the rcu_read_lock inside the loop, we can't assume
that files->fdt will remain unchanged (and not freed) between
iterations.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We were accounting for the cleanmarker by calling jffs2_link_node_ref()
(without locking!), which adjusted both superblock and per-eraseblock
accounting, subtracting the size of the cleanmarker from {jeb,c}->free_size
and adding it to {jeb,c}->used_size.
But only _then_ were we adding the size of the newly-erased block back
to the superblock counts, and we were adding each of jeb->{free,used}_size
to the corresponding superblock counts. Thus, the size of the cleanmarker
was effectively subtracted from the superblock's free_size _twice_.
Fix this, by always adding a full eraseblock size to c->free_size when
we've erased a block. And call jffs2_link_node_ref() under the proper
lock, while we're at it.
Thanks to Alexander Yurchenko and/or Damir Shayhutdinov for (almost)
pinpointing the problem.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm:
dlm: linux/{dlm,dlm_device}.h: cleanup for userspace
dlm: common max length definitions
dlm: move plock code from gfs2
dlm: recover nodes that are removed and re-added
dlm: save master info after failed no-queue request
dlm: make dlm_print_rsb() static
dlm: match signedness between dlm_config_info and cluster_set
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-udf-2.6: (41 commits)
udf: use crc_itu_t from lib instead of udf_crc
udf: Fix compilation warnings when UDF debug is on
udf: Fix bug in VAT mapping code
udf: Add read-only support for 2.50 UDF media
udf: Fix handling of multisession media
udf: Mount filesystem read-only if it has pseudooverwrite partition
udf: Handle VAT packed inside inode properly
udf: Allow loading of VAT inode
udf: Fix detection of VAT version
udf: Silence warning about accesses beyond end of device
udf: Improve anchor block detection
udf: Cleanup anchor block detection.
udf: Move processing of virtual partitions
udf: Move filling of partition descriptor info into a separate function
udf: Improve error recovery on mount
udf: Cleanup volume descriptor sequence processing
udf: fix anchor point detection
udf: Remove declarations of arrays of size UDF_NAME_LEN (256 bytes)
udf: Remove checking of existence of filename in udf_add_entry()
udf: Mark udf_process_sequence() as noinline
...
We have a problem in scsi_transport_spi in that we need to customise
not only the visibility of the attributes, but also their mode. Fix
this by making the is_visible() callback return a mode, with 0
indicating is not visible.
Also add a sysfs_update_group() API to allow us to change either the
visibility or mode of the files at any time on the fly.
Acked-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Add the write verification buffer to the dataflash. The mtd_dataflash has
the CONFIG_DATAFLASH_WRITE_VERIFY so is better a change to Kconfig.
Signed-off-by: Michael Trimarchi <trimarchimichael@yahoo.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
fs/jffs2/gc.c:1147:29: warning: symbol 'jeb' shadows an earlier one
fs/jffs2/gc.c:1084:89: originally declared here
fs/jffs2/gc.c:1197:29: warning: symbol 'jeb' shadows an earlier one
fs/jffs2/gc.c:1084:89: originally declared here
Rename the unused 'jeb' argument to avoid this. We could potentially
remove the argument, but GCC should be doing that anyway.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
fs/jffs2/write.c:585:28: warning: symbol 'fd' shadows an earlier one
fs/jffs2/write.c:536:27: originally declared here
No need to redeclare fd, use the original one, after this point,
fd is always reassigned before it used again.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
fs/jffs2/nodemgmt.c:60:8: warning: symbol 'ret' shadows an earlier one
fs/jffs2/nodemgmt.c:45:6: originally declared here
(reported by Harvey Harrison)
Just remove the offending declaration of 'int ret' and use the earlier one.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
fs/jffs2/ioctl.c:14:5: warning: symbol 'jffs2_ioctl' was not declared.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Further reduction of stack footprint (sys_pivot_root());
lose useless BKL in there, while we are at it.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Taking namespace_sem shared there isn't worth the trouble, especially with
vfsmount ID allocation about to be added. That way we know that umount_tree(),
copy_tree() and clone_mnt() are _always_ serialized by namespace_sem.
umount_tree() still needs vfsmount_lock (it manipulates hash chains, among
other things), but that's a separate story.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/juhl/trivial: (24 commits)
DOC: A couple corrections and clarifications in USB doc.
Generate a slightly more informative error msg for bad HZ
fix typo "is" -> "if" in Makefile
ext*: spelling fix prefered -> preferred
DOCUMENTATION: Use newer DEFINE_SPINLOCK macro in docs.
KEYS: Fix the comment to match the file name in rxrpc-type.h.
RAID: remove trailing space from printk line
DMA engine: typo fixes
Remove unused MAX_NODES_SHIFT
MAINTAINERS: Clarify access to OCFS2 development mailing list.
V4L: Storage class should be before const qualifier (sn9c102)
V4L: Storage class should be before const qualifier
sonypi: Storage class should be before const qualifier
intel_menlow: Storage class should be before const qualifier
DVB: Storage class should be before const qualifier
arm: Storage class should be before const qualifier
ALSA: Storage class should be before const qualifier
acpi: Storage class should be before const qualifier
firmware_sample_driver.c: fix coding style
MAINTAINERS: Add ati_remote2 driver
...
Fixed up trivial conflicts in firmware_sample_driver.c
* 'for-2.6.26' of git://git.kernel.dk/linux-2.6-block:
block: fix blk_register_queue() return value
block: fix memory hotplug and bouncing in block layer
block: replace remaining __FUNCTION__ occurrences
Kconfig: clean up block/Kconfig help descriptions
cciss: fix warning oops on rmmod of driver
cciss: Fix race between disk-adding code and interrupt handler
block: move the padding adjustment to blk_rq_map_sg
block: add bio_copy_user_iov support to blk_rq_map_user_iov
block: convert bio_copy_user to bio_copy_user_iov
loop: manage partitions in disk image
cdrom: use kmalloced buffers instead of buffers on stack
cdrom: make unregister_cdrom() return void
cdrom: use list_head for cdrom_device_info list
cdrom: protect cdrom_device_info list by mutex
cdrom: cleanup hardcoded error-code
cdrom: remove ifdef CONFIG_SYSCTL
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-2.6: (36 commits)
SCSI: convert struct class_device to struct device
DRM: remove unused dev_class
IB: rename "dev" to "srp_dev" in srp_host structure
IB: convert struct class_device to struct device
memstick: convert struct class_device to struct device
driver core: replace remaining __FUNCTION__ occurrences
sysfs: refill attribute buffer when reading from offset 0
PM: Remove destroy_suspended_device()
Firmware: add iSCSI iBFT Support
PM: Remove legacy PM (fix)
Kobject: Replace list_for_each() with list_for_each_entry().
SYSFS: Explicitly include required header file slab.h.
Driver core: make device_is_registered() work for class devices
PM: Convert wakeup flag accessors to inline functions
PM: Make wakeup flags available whenever CONFIG_PM is set
PM: Fix misuse of wakeup flag accessors in serial core
Driver core: Call device_pm_add() after bus_add_device() in device_add()
PM: Handle device registrations during suspend/resume
block: send disk "change" event for rescan_partitions()
sysdev: detect multiple driver registrations
...
Fixed trivial conflict in include/linux/memory.h due to semaphore header
file change (made irrelevant by the change to mutex).
These are small cleanups all over the tree.
Trivial style and comment changes to
fs/select.c, kernel/signal.c, kernel/stop_machine.c & mm/pdflush.c
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Add central definitions for max lockspace name length and max resource
name length. The lack of central definitions has resulted in scattered
private definitions which we can now clean up, including an unused one
in dlm_device.h.
Signed-off-by: David Teigland <teigland@redhat.com>
Move the code that handles cluster posix locks from gfs2 into the dlm
so that it can be used by both gfs2 and ocfs2.
Signed-off-by: David Teigland <teigland@redhat.com>
If a node is removed from a lockspace, and then added back before the
dlm is notified of the removal, the dlm will not detect the removal
and won't clear the old state from the node. This is fixed by using a
list of added nodes so the membership recovery can detect when a newly
added node is already in the member list.
Signed-off-by: David Teigland <teigland@redhat.com>
When a NOQUEUE request fails, the rsb res_master field is unnecessarily
reset to -1, instead of leaving the valid master setting in place. We
want to save the looked-up master values while the rsb is on the "toss
list" so that another lookup can be avoided if the rsb is soon reused.
The fix is to simply leave res_master value alone.
Signed-off-by: David Teigland <teigland@redhat.com>
cluster_set is only called from the macro CLUSTER_ATTR which defines read/write
access functions. Make the signedness match to avoid sparse warnings every time
CLUSTER_ATTR is used (lines 149-159) all of the form:
fs/dlm/config.c:149:1: warning: incorrect type in argument 3 (different signedness)
fs/dlm/config.c:149:1: expected unsigned int *info_field
fs/dlm/config.c:149:1: got int extern [toplevel] *<noident>
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David Teigland <teigland@redhat.com>
This patch enables bio_copy_user to take struct sg_iovec (renamed
bio_copy_user_iov). bio_copy_user uses bio_copy_user_iov internally as
bio_map_user uses bio_map_user_iov.
The major changes are:
- adds sg_iovec array to struct bio_map_data
- adds __bio_copy_iov that copy data between bio and
sg_iovec. bio_copy_user_iov and bio_uncopy_user use it.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Requiring userspace to close and re-open sysfs attributes has been the
policy since before 2.6.12. It allows userspace to get a consistent
snapshot of kernel state and consume it with incremental reads and seeks.
Now, if the file position is zero the kernel assumes userspace wants to see
the new value. The application for this change is to allow a userspace
RAID metadata handler to check the state of an array without causing any
memory allocations. Thus not causing writeback to a raid array that might
be blocked waiting for userspace to take action.
Cc: Neil Brown <neilb@suse.de>
Acked-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
After an experimental deletion of the unnecessary inclusion of
<linux/slab.h> from the header file <linux/percpu.h>, the following
files under fs/sysfs were exposed as needing to explicitly include
<linux/slab.h>.
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Userspace likes to get notified that the disk may have changed, when
rescan_partitions() is called after partitioning or media change. It will
make it possible to update the state of the disk with the "change" event,
before the following partition "add" events are handled.
Cc: David Zeuthen <david@fubar.dk>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
There is possible NULL pointer dereference if kstr[n]dup failed.
So fix them for safety.
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We need to try to ensure that we always use the same credentials whenever
we re-establish the clientid on the server. If not, the server won't
recognise that we're the same client, and so may not allow us to recover
state.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
With the recent change to generic creds, we can no longer use
cred->cr_ops->cr_name to distinguish between RPCSEC_GSS principals and
AUTH_SYS/AUTH_NULL identities. Replace it with the rpc_authops->au_name
instead...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Benny points out that zero-padding of multiword bitfields is necessary,
and that delimiting each word is nice to avoid endianess confusion.
bhalevy: without zero padding output can be ambiguous. Also,
since the printed array of two 32-bit unsigned integers is not a
64-bit number, delimiting the output with a semicolon makes more sense.
Signed-off-by: Fred Isaman <iisaman@citi.umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
All use sites for nfs{,4}_stat_to_errno negate their return value.
It's more efficient to return a negative error from the stat_to_errno convertors
rather than negating its return value everywhere. This also produces slightly
smaller code.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Now that we've added the 'generic' credentials (that are independent of the
rpc_client) to the nfs_open_context, we can use those in the NLM client to
ensure that the lock/unlock requests are authenticated to whoever
originally opened the file.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Both NLM and NFSv4 should be able to clean up adequately in the case where
the user interrupts the RPC call...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We shouldn't remove the lock from the list of blocked locks until the
CANCEL call has completed since we may be racing with a GRANTED callback.
Also ensure that we send an UNLOCK if the CANCEL request failed. Normally
that should only happen if the process gets hit with a fatal signal.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently, it returns success as long as the RPC call was sent. We'd like
to know if the CANCEL operation succeeded on the server.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Peter Staubach comments:
> In the course of investigating testing failures in the locking phase of
> the Connectathon testsuite, I discovered a couple of things. One was
> that one of the tests in the locking tests was racy when it didn't seem
> to need to be and two, that the NFS client asynchronously releases locks
> when a process is exiting.
...
> The Single UNIX Specification Version 3 specifies that: "All locks
> associated with a file for a given process shall be removed when a file
> descriptor for that file is closed by that process or the process holding
> that file descriptor terminates.".
>
> This does not specify whether those locks must be released prior to the
> completion of the exit processing for the process or not. However,
> general assumptions seem to be that those locks will be released. This
> leads to more deterministic behavior under normal circumstances.
The following patch converts the NFSv2/v3 locking code to use the same
mechanism as NFSv4 for sending asynchronous RPC calls and then waiting for
them to complete. This ensures that the UNLOCK and CANCEL RPC calls will
complete even if the user interrupts the call, yet satisfies the
above request for synchronous behaviour on process exit.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When we replace the existing synchronous RPC calls with asynchronous calls,
the reference count will be needed in order to allow us to examine the
result of the RPC call.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Also fix up nlmclnt_lock() so that it doesn't pass modified versions of
fl->fl_flags to nlmclnt_cancel() and other helpers.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
It is quite possible that the OPEN, CLOSE, LOCK, LOCKU,... compounds fail
before the actual stateful operation has been executed (for instance in the
PUTFH call). There is no way to tell from the overall status result which
operations were executed from the COMPOUND.
The fix is to move incrementing of the sequence id into the XDR layer,
so that we do it as we process the results from the stateful operation.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
There should be no need to invalidate a perfectly good state owner just
because of a stale filehandle. Doing so can cause the state recovery code
to break, since nfs4_get_renew_cred() and nfs4_get_setclientid_cred() rely
on finding active state owners.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
In the case of readpage() we need to ensure that the pages get unlocked,
and that the error is flagged.
In the case of O_DIRECT, we need to ensure that the pages are all released.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
It is possible for nfs_wb_page() to sometimes exit with 0 return value, yet
the page is left in a dirty state.
For instance in the case where the server rebooted, and the COMMIT request
failed, then all the previously "clean" pages which were cached by the
server, but were not guaranteed to have been writted out to disk,
have to be redirtied and resent to the server.
The fix is to have nfs_wb_page_priority() check that the page is clean
before it exits...
This fixes a condition that triggers the BUG_ON(PagePrivate(page)) in
nfs_create_request() when we're in the nfs_readpage() path.
Also eliminate a redundant BUG_ON(!PageLocked(page)) while we're at it. It
turns out that clear_page_dirty_for_io() has the exact same test.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
There have been a few oopses caused by 'struct file's with NULL f_vfsmnts.
There was also a set of potentially missed mnt_want_write()s from
dentry_open() calls.
This patch provides a very simple debugging framework to catch these kinds of
bugs. It will WARN_ON() them, but should stop us from having any oopses or
mnt_writer count imbalances.
I'm quite convinced that this is a good thing because it found bugs in the
stuff I was working on as soon as I wrote it.
[hch: made it conditional on a debug option.
But it's still a little bit too ugly]
[hch: merged forced remount r/o fix from Dave and akpm's fix for the fix]
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Originally from: Herbert Poetzl <herbert@13thfloor.at>
This is the core of the read-only bind mount patch set.
Note that this does _not_ add a "ro" option directly to the bind mount
operation. If you require such a mount, you must first do the bind, then
follow it up with a 'mount -o remount,ro' operation:
If you wish to have a r/o bind mount of /foo on bar:
mount --bind /foo /bar
mount -o remount,ro /bar
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This is the real meat of the entire series. It actually
implements the tracking of the number of writers to a mount.
However, it causes scalability problems because there can be
hundreds of cpus doing open()/close() on files on the same mnt at
the same time. Even an atomic_t in the mnt has massive scalaing
problems because the cacheline gets so terribly contended.
This uses a statically-allocated percpu variable. All want/drop
operations are local to a cpu as long that cpu operates on the same
mount, and there are no writer count imbalances. Writer count
imbalances happen when a write is taken on one cpu, and released
on another, like when an open/close pair is performed on two
Upon a remount,ro request, all of the data from the percpu
variables is collected (expensive, but very rare) and we determine
if there are any outstanding writers to the mount.
I've written a little benchmark to sit in a loop for a couple of
seconds in several cpus in parallel doing open/write/close loops.
http://sr71.net/~dave/linux/openbench.c
The code in here is a a worst-possible case for this patch. It
does opens on a _pair_ of files in two different mounts in parallel.
This should cause my code to lose its "operate on the same mount"
optimization completely. This worst-case scenario causes a 3%
degredation in the benchmark.
I could probably get rid of even this 3%, but it would be more
complex than what I have here, and I think this is getting into
acceptable territory. In practice, I expect writing more than 3
bytes to a file, as well as disk I/O to mask any effects that this
has.
(To get rid of that 3%, we could have an #defined number of mounts
in the percpu variable. So, instead of a CPU getting operate only
on percpu data when it accesses only one mount, it could stay on
percpu data when it only accesses N or fewer mounts.)
[AV] merged fix for __clear_mnt_mount() stepping on freed vfsmount
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
If we depend on the inodes for writeability, we will not catch the r/o mounts
when implemented.
This patches uses __mnt_want_write(). It does not guarantee that the mount
will stay writeable after the check. But, this is OK for one of the checks
because it is just for a printk().
The other two are probably unnecessary and duplicate existing checks in the
VFS. This won't make them better checks than before, but it will make them
detect r/o mounts.
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Elevate the write count during the xfs m/ctime updates.
XFS has to do it's own timestamp updates due to an unfortunate VFS
design limitation, so it will have to track writers by itself aswell.
[hch: split out from the touch_atime patch as it's not related to it at all]
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
It is OK to let access() go without using a mnt_want/drop_write() pair because
it doesn't actually do writes to the filesystem, and it is inherently racy
anyway. This is a rare case when it is OK to use __mnt_is_readonly()
directly.
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
chown/chmod,etc... don't call permission in the same way that the normal
"open for write" calls do. They still write to the filesystem, so bump the
write count during these operations.
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This is the first really tricky patch in the series. It elevates the writer
count on a mount each time a non-special file is opened for write.
We used to do this in may_open(), but Miklos pointed out that __dentry_open()
is used as well to create filps. This will cover even those cases, while a
call in may_open() would not have.
There is also an elevated count around the vfs_create() call in open_namei().
See the comments for more details, but we need this to fix a 'create, remount,
fail r/w open()' race.
Some filesystems forego the use of normal vfs calls to create
struct files. Make sure that these users elevate the mnt
writer count because they will get __fput(), and we need
to make sure they're balanced.
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Some ioctl()s can cause writes to the filesystem. Take these, and make them
use mnt_want/drop_write() instead.
[AV: updated]
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Now includes fix for oops seen by akpm.
"never let a libc developer write your kernel code" - hch
"nor, apparently, a kernel developer" - akpm
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Cc: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Remove handling of NULL mnt while we are at it - that can't happen these days.
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This basically audits the callers of xattr_permission(), which calls
permission() and can perform writes to the filesystem.
[AV: add missing parts - removexattr() and nfsd posix acls, plug for a leak
spotted by Miklos]
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This also uses the little helper in the NFS code to make an if() a little bit
less ugly. We introduced the helper at the beginning of the series.
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This takes care of all of the direct callers of vfs_mknod().
Since a few of these cases also handle normal file creation
as well, this also covers some calls to vfs_create().
So that we don't have to make three mnt_want/drop_write()
calls inside of the switch statement, we move some of its
logic outside of the switch and into a helper function
suggested by Christoph.
This also encapsulates a fix for mknod(S_IFREG) that Miklos
found.
[AV: merged mkdir handling, added missing nfsd pieces]
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
