... and deal with short writes properly - the output might be to pipe, after
all; as it is, e.g. no-MMU case of elf_fdpic coredump can write a whole lot
more than a page worth of data at one call.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
dump_write() analog, takes core_dump_params instead of file,
keeps track of the amount written in cprm->written and checks for
cprm->limit. Start using it in binfmt_elf.c...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The only thing we need it for is alt-sysrq-r (emergency remount r/o)
and these days we can do just as well without going through the
list of files.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* RCU-delayed freeing of vfsmounts
* vfsmount_lock replaced with a seqlock (mount_lock)
* sequence number from mount_lock is stored in nameidata->m_seq and
used when we exit RCU mode
* new vfsmount flag - MNT_SYNC_UMOUNT. Set by umount_tree() when its
caller knows that vfsmount will have no surviving references.
* synchronize_rcu() done between unlocking namespace_sem in namespace_unlock()
and doing pending mntput().
* new helper: legitimize_mnt(mnt, seq). Checks the mount_lock sequence
number against seq, then grabs reference to mnt. Then it rechecks mount_lock
again to close the race and either returns success or drops the reference it
has acquired. The subtle point is that in case of MNT_SYNC_UMOUNT we can
simply decrement the refcount and sod off - aforementioned synchronize_rcu()
makes sure that final mntput() won't come until we leave RCU mode. We need
that, since we don't want to end up with some lazy pathwalk racing with
umount() and stealing the final mntput() from it - caller of umount() may
expect it to return only once the fs is shut down and we don't want to break
that. In other cases (i.e. with MNT_SYNC_UMOUNT absent) we have to do
full-blown mntput() in case of mount_lock sequence number mismatch happening
just as we'd grabbed the reference, but in those cases we won't be stealing
the final mntput() from anything that would care.
* mntput_no_expire() doesn't lock anything on the fast path now. Incidentally,
SMP and UP cases are handled the same way - no ifdefs there.
* normal pathname resolution does *not* do any writes to mount_lock. It does,
of course, bump the refcounts of vfsmount and dentry in the very end, but that's
it.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
__get_cpu_var() is used for multiple purposes in the kernel source. One of
them is address calculation via the form &__get_cpu_var(x). This calculates
the address for the instance of the percpu variable of the current processor
based on an offset.
Other use cases are for storing and retrieving data from the current
processors percpu area. __get_cpu_var() can be used as an lvalue when
writing data or on the right side of an assignment.
__get_cpu_var() is defined as :
#define __get_cpu_var(var) (*this_cpu_ptr(&(var)))
__get_cpu_var() always only does an address determination. However, store
and retrieve operations could use a segment prefix (or global register on
other platforms) to avoid the address calculation.
this_cpu_write() and this_cpu_read() can directly take an offset into a
percpu area and use optimized assembly code to read and write per cpu
variables.
This patch converts __get_cpu_var into either an explicit address
calculation using this_cpu_ptr() or into a use of this_cpu operations that
use the offset. Thereby address calculations are avoided and less registers
are used when code is generated.
At the end of the patch set all uses of __get_cpu_var have been removed so
the macro is removed too.
The patch set includes passes over all arches as well. Once these operations
are used throughout then specialized macros can be defined in non -x86
arches as well in order to optimize per cpu access by f.e. using a global
register that may be set to the per cpu base.
Transformations done to __get_cpu_var()
1. Determine the address of the percpu instance of the current processor.
DEFINE_PER_CPU(int, y);
int *x = &__get_cpu_var(y);
Converts to
int *x = this_cpu_ptr(&y);
2. Same as #1 but this time an array structure is involved.
DEFINE_PER_CPU(int, y[20]);
int *x = __get_cpu_var(y);
Converts to
int *x = this_cpu_ptr(y);
3. Retrieve the content of the current processors instance of a per cpu
variable.
DEFINE_PER_CPU(int, y);
int x = __get_cpu_var(y)
Converts to
int x = __this_cpu_read(y);
4. Retrieve the content of a percpu struct
DEFINE_PER_CPU(struct mystruct, y);
struct mystruct x = __get_cpu_var(y);
Converts to
memcpy(&x, this_cpu_ptr(&y), sizeof(x));
5. Assignment to a per cpu variable
DEFINE_PER_CPU(int, y)
__get_cpu_var(y) = x;
Converts to
this_cpu_write(y, x);
6. Increment/Decrement etc of a per cpu variable
DEFINE_PER_CPU(int, y);
__get_cpu_var(y)++
Converts to
this_cpu_inc(y)
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There were two places where return value from bdi_init was not tested.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Many of the uses of get_random_bytes() do not actually need
cryptographically secure random numbers. Replace those uses with a
call to prandom_u32(), which is faster and which doesn't consume
entropy from the /dev/random driver.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If we failed to init&add kobject when fill_super, stats info and proc object of
f2fs will not be released.
We should free them before we finish fill_super.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
use genernal method supported by kernel
o changes from v1
If any waiter exists at end io, wake up it.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Commit ec22ba8e ("ext4: disable merging of uninitialized extents")
ensured that if either extent under consideration is uninit, we
decline to merge, and ext4_can_extents_be_merged() returns false.
So there is no need for the caller to then test whether the
extent under consideration is unitialized; if it were, we
wouldn't have gotten that far.
The comments were also inaccurate; ext4_can_extents_be_merged()
no longer XORs the states, it fails if *either* is uninit.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Pull CIFS updates from Steve French:
"Includes a couple of fixes, plus changes to make multiplex identifiers
easier to read and correlate with network traces, and a set of
enhancements for SMB3 dialect. Also adds support for per-file
compression for both cifs and smb2/smb3 ("chattr +c filename).
Should have at least one other merge request ready by next week with
some new SMB3 security features and copy offload support"
* 'for-linus' of git://git.samba.org/sfrench/cifs-2.6:
Query network adapter info at mount time for debugging
Fix unused variable warning when CIFS POSIX disabled
Allow setting per-file compression via CIFS protocol
Query File System Alignment
Query device characteristics at mount time from server on SMB2/3 not just on cifs mounts
cifs: Send a logoff request before removing a smb session
cifs: Make big endian multiplex ID sequences monotonic on the wire
cifs: Remove redundant multiplex identifier check from check_smb_hdr()
Query file system attributes from server on SMB2, not just cifs, mounts
Allow setting per-file compression via SMB2/3
Fix corrupt SMB2 ioctl requests
Pull NFS client updates from Trond Myklebust:
"Highlights include:
- Changes to the RPC socket code to allow NFSv4 to turn off
timeout+retry:
* Detect TCP connection breakage through the "keepalive" mechanism
- Add client side support for NFSv4.x migration (Chuck Lever)
- Add support for multiple security flavour arguments to the "sec="
mount option (Dros Adamson)
- fs-cache bugfixes from David Howells:
* Fix an issue whereby caching can be enabled on a file that is
open for writing
- More NFSv4 open code stable bugfixes
- Various Labeled NFS (selinux) bugfixes, including one stable fix
- Fix buffer overflow checking in the RPCSEC_GSS upcall encoding"
* tag 'nfs-for-3.13-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (68 commits)
NFSv4.2: Remove redundant checks in nfs_setsecurity+nfs4_label_init_security
NFSv4: Sanity check the server reply in _nfs4_server_capabilities
NFSv4.2: encode_readdir - only ask for labels when doing readdirplus
nfs: set security label when revalidating inode
NFSv4.2: Fix a mismatch between Linux labeled NFS and the NFSv4.2 spec
NFS: Fix a missing initialisation when reading the SELinux label
nfs: fix oops when trying to set SELinux label
nfs: fix inverted test for delegation in nfs4_reclaim_open_state
SUNRPC: Cleanup xs_destroy()
SUNRPC: close a rare race in xs_tcp_setup_socket.
SUNRPC: remove duplicated include from clnt.c
nfs: use IS_ROOT not DCACHE_DISCONNECTED
SUNRPC: Fix buffer overflow checking in gss_encode_v0_msg/gss_encode_v1_msg
SUNRPC: gss_alloc_msg - choose _either_ a v0 message or a v1 message
SUNRPC: remove an unnecessary if statement
nfs: Use PTR_ERR_OR_ZERO in 'nfs/nfs4super.c'
nfs: Use PTR_ERR_OR_ZERO in 'nfs41_callback_up' function
nfs: Remove useless 'error' assignment
sunrpc: comment typo fix
SUNRPC: Add correct rcu_dereference annotation in rpc_clnt_set_transport
...
This reverts commit cb26a31157.
It mysteriously causes NetworkManager to not find the wireless device
for me. As far as I can tell, Tejun *meant* for this commit to not make
any semantic changes, but there clearly are some. So revert it, taking
into account some of the calling convention changes that happened in
this area in subsequent commits.
Cc: Tejun Heo <tj@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull driver core / sysfs patches from Greg KH:
"Here's the big driver core / sysfs update for 3.13-rc1.
There's lots of dev_groups updates for different subsystems, as they
all get slowly migrated over to the safe versions of the attribute
groups (removing userspace races with the creation of the sysfs
files.) Also in here are some kobject updates, devres expansions, and
the first round of Tejun's sysfs reworking to enable it to be used by
other subsystems as a backend for an in-kernel filesystem.
All of these have been in linux-next for a while with no reported
issues"
* tag 'driver-core-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (83 commits)
sysfs: rename sysfs_assoc_lock and explain what it's about
sysfs: use generic_file_llseek() for sysfs_file_operations
sysfs: return correct error code on unimplemented mmap()
mdio_bus: convert bus code to use dev_groups
device: Make dev_WARN/dev_WARN_ONCE print device as well as driver name
sysfs: separate out dup filename warning into a separate function
sysfs: move sysfs_hash_and_remove() to fs/sysfs/dir.c
sysfs: remove unused sysfs_get_dentry() prototype
sysfs: honor bin_attr.attr.ignore_lockdep
sysfs: merge sysfs_elem_bin_attr into sysfs_elem_attr
devres: restore zeroing behavior of devres_alloc()
sysfs: fix sysfs_write_file for bin file
input: gameport: convert bus code to use dev_groups
input: serio: remove bus usage of dev_attrs
input: serio: use DEVICE_ATTR_RO()
i2o: convert bus code to use dev_groups
memstick: convert bus code to use dev_groups
tifm: convert bus code to use dev_groups
virtio: convert bus code to use dev_groups
ipack: convert bus code to use dev_groups
...
Introduce flag KM_ZERO which is used to alloc zeroed entry, and convert
kmem_{zone_}zalloc to call kmem_{zone_}alloc() with KM_ZERO directly,
in order to avoid the setting to zero step.
And following Dave's suggestion, make kmem_{zone_}zalloc static inline
into kmem.h as they're now just a simple wrapper.
V2:
Make kmem_{zone_}zalloc static inline into kmem.h as Dave suggested.
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
To help track down AGI/AGF lock ordering issues, I added these
tracepoints to tell us when an AGI or AGF is read and locked. With
these we can now determine if the lock ordering goes wrong from
tracing captures.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
I debugging a log tail issue on a RHEL6 kernel, I added these trace
points to trace log items being added, moved and removed in the AIL
and how that affected the log tail LSN that was written to the log.
They were very helpful in that they immediately identified the cause
of the problem being seen. Hence I'd like to always have them
available for use.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
A NULL point should avoid to be used in destroy_segment_manager after allocating
memory fail for f2fs_sm_info.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Conflicts:
kernel/Makefile
There are conflicts in kernel/Makefile due to file moving in the
scheduler tree - resolve them.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Move the audit_bprm() call from search_binary_handler() to exec_binprm(). This
allows us to get rid of the mm member of struct audit_aux_data_execve since
bprm->mm will equal current->mm.
This also mitigates the issue that ->argc could be modified by the
load_binary() call in search_binary_handler().
audit_bprm() was being called to add an AUDIT_EXECVE record to the audit
context every time search_binary_handler() was recursively called. Only one
reference is necessary.
Reported-by: Oleg Nesterov <onestero@redhat.com>
Cc: Eric Paris <eparis@redhat.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
---
This patch is against 3.11, but was developed on Oleg's post-3.11 patches that
introduce exec_binprm().
Historically, when a syscall that creates a dentry fails, you get an audit
record that looks something like this (when trying to create a file named
"new" in "/tmp/tmp.SxiLnCcv63"):
type=PATH msg=audit(1366128956.279:965): item=0 name="/tmp/tmp.SxiLnCcv63/new" inode=2138308 dev=fd:02 mode=040700 ouid=0 ogid=0 rdev=00:00 obj=staff_u:object_r:user_tmp_t:s15:c0.c1023
This record makes no sense since it's associating the inode information for
"/tmp/tmp.SxiLnCcv63" with the path "/tmp/tmp.SxiLnCcv63/new". The recent
patch I posted to fix the audit_inode call in do_last fixes this, by making it
look more like this:
type=PATH msg=audit(1366128765.989:13875): item=0 name="/tmp/tmp.DJ1O8V3e4f/" inode=141 dev=fd:02 mode=040700 ouid=0 ogid=0 rdev=00:00 obj=staff_u:object_r:user_tmp_t:s15:c0.c1023
While this is more correct, if the creation of the file fails, then we
have no record of the filename that the user tried to create.
This patch adds a call to audit_inode_child to may_create. This creates
an AUDIT_TYPE_CHILD_CREATE record that will sit in place until the
create succeeds. When and if the create does succeed, then this record
will be updated with the correct inode info from the create.
This fixes what was broken in commit bfcec708.
Commit 79f6530c should also be backported to stable v3.7+.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
If a task has CAP_AUDIT_CONTROL allow that task to unset their loginuid.
This would allow a child of that task to set their loginuid without
CAP_AUDIT_CONTROL. Thus when launching a new login daemon, a
priviledged helper would be able to unset the loginuid and then the
daemon, which may be malicious user facing, do not need priv to function
correctly.
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Commit 8e3dffc651 "Ext2: mark inode dirty after the function
dquot_free_block_nodirty is called" unveiled a bug in __ext2_get_block()
called from ext2_get_xip_mem(). That function called ext2_get_block()
mistakenly asking it to map 0 blocks while 1 was intended. Before the
above mentioned commit things worked out fine by luck but after that commit
we started returning that we allocated 0 blocks while we in fact
allocated 1 block and thus allocation was looping until all blocks in
the filesystem were exhausted.
Fix the problem by properly asking for one block and also add assertion
in ext2_get_blocks() to catch similar problems.
Reported-and-tested-by: Andiry Xu <andiry.xu@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
All async fuse requests must be supplied with extra reference to a fuse
file. This is necessary to ensure that the fuse file is not released until
all in-flight requests are completed. Fuse secondary writeback requests
must obey this rule as well.
Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
BDI_WRITTEN counter is used to estimate bdi bandwidth. It must be
incremented every time as bdi ends page writeback. No matter whether it
was fulfilled by actual write or by discarding the request (e.g. due to
shrunk i_size).
Note that even before writepages patches, the case "Got truncated off
completely" was handled in fuse_send_writepage() by calling
fuse_writepage_finish() which updated BDI_WRITTEN unconditionally.
Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
If writeback happens while fuse is in FUSE_NOWRITE condition, the request
will be queued but not processed immediately (see fuse_flush_writepages()).
Until FUSE_NOWRITE becomes relaxed, more writebacks can happen. They will
be queued as "secondary" requests to that first ("primary") request.
Existing implementation crops only primary request. This is not correct
because a subsequent extending write(2) may increase i_size and then
secondary requests won't be cropped properly. The result would be stale
data written to the server to a file offset where zeros must be.
Similar problem may happen if secondary requests are attached to an
in-flight request that was already cropped.
The patch solves the issue by cropping all secondary requests in
fuse_writepage_end(). Thanks to Miklos for idea.
Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
fuse_writepage_in_flight() returns false if it fails to find request with
given index in fi->writepages. Then the caller proceeds with populating
data->orig_pages[] and incrementing req->num_pages. Hence,
fuse_writepage_in_flight() must revert changes it made in request before
returning false.
Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
This reverts commit 7ebe40f203. We forgot
the nfs4_put_delegation call in fs/nfsd/nfs4callback.c which should not
be unhashing the stateid. This lead to warnings from the idr code when
we tried to removed id's twice.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We already check for nfs_server_capable(inode, NFS_CAP_SECURITY_LABEL)
in nfs4_label_alloc()
We check the minor version in _nfs4_server_capabilities before setting
NFS_CAP_SECURITY_LABEL.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We don't want to be setting capabilities and/or requesting attributes
that are not appropriate for the NFSv4 minor version.
- Ensure that we clear the NFS_CAP_SECURITY_LABEL capability when appropriate
- Ensure that we limit the attribute bitmasks to the mounted_on_fileid
attribute and less for NFSv4.0
- Ensure that we limit the attribute bitmasks to suppattr_exclcreat and
less for NFSv4.1
- Ensure that we limit it to change_sec_label or less for NFSv4.2
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently, if the server is doing NFSv4.2 and supports labeled NFS, then
our on-the-wire READDIR request ends up asking for the label information,
which is then ignored unless we're doing readdirplus.
This patch ensures that READDIR doesn't ask the server for label information
at all unless the readdir->bitmask contains the FATTR4_WORD2_SECURITY_LABEL
attribute, and the readdir->plus flag is set.
While we're at it, optimise away the 3rd bitmap field if it is zero.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently, we fetch the security label when revalidating an inode's
attributes, but don't apply it. This is in contrast to the readdir()
codepath where we do apply label changes.
Cc: Dave Quigley <dpquigl@davequigley.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Removing an inode from the namespace involves removing the directory
entry and dropping the link count on the inode. Removing the
directory entry can result in locking an AGF (directory blocks were
freed) and removing a link count can result in placing the inode on
an unlinked list which results in locking an AGI.
The big problem here is that we have an ordering constraint on AGF
and AGI locking - inode allocation locks the AGI, then can allocate
a new extent for new inodes, locking the AGF after the AGI.
Similarly, freeing the inode removes the inode from the unlinked
list, requiring that we lock the AGI first, and then freeing the
inode can result in an inode chunk being freed and hence freeing
disk space requiring that we lock an AGF.
Hence the ordering that is imposed by other parts of the code is AGI
before AGF. This means we cannot remove the directory entry before
we drop the inode reference count and put it on the unlinked list as
this results in a lock order of AGF then AGI, and this can deadlock
against inode allocation and freeing. Therefore we must drop the
link counts before we remove the directory entry.
This is still safe from a transactional point of view - it is not
until we get to xfs_bmap_finish() that we have the possibility of
multiple transactions in this operation. Hence as long as we remove
the directory entry and drop the link count in the first transaction
of the remove operation, there are no transactional constraints on
the ordering here.
Change the ordering of the operations in the xfs_remove() function
to align the ordering of AGI and AGF locking to match that of the
rest of the code.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
