We may sleep inside a the lock, so use a mutex rather than spinlock.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
For block devices the pagecache is associated with the inode
on bdevfs, not with the aliasing ones on the mountable filesystems.
The latter have its own ->i_data empty and ->i_mapping pointing
to the (unique per major/minor) bdevfs inode. That guarantees
cache coherence between all block device inodes with the same
device number.
Eviction of an alias inode has no business trying to evict the
pages belonging to bdevfs one; moreover, ->i_mapping is only
safe to access when the thing is opened. At the time of
->evict_inode() the victim is definitely *not* opened. We are
about to kill the address space embedded into struct inode
(inode->i_data) and that's what we need to empty of any pages.
9p instance tries to empty inode->i_mapping instead, which is
both unsafe and bogus - if we have several device nodes with
the same device number in different places, closing one of them
should not try to empty the (shared) page cache.
Fortunately, other instances in the tree are OK; they are
evicting from &inode->i_data instead, as 9p one should.
Cc: stable@vger.kernel.org # v2.6.32+, ones prior to 2.6.36 need only half of that
Reported-by: "Suzuki K. Poulose" <Suzuki.Poulose@arm.com>
Tested-by: "Suzuki K. Poulose" <Suzuki.Poulose@arm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Now that the xattr handler is passed to the xattr handler operations, we
can use the same get and set operations for the user, trusted, and security
xattr namespaces. In those namespaces, we can access the full attribute
name by "reattaching" the name prefix the vfs has skipped for us. Add a
xattr_full_name helper to make this obvious in the code.
For the "system.posix_acl_access" and "system.posix_acl_default"
attributes, handler->prefix is the full attribute name; the suffix is the
empty string.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: v9fs-developer@lists.sourceforge.net
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The xattr_handler operations are currently all passed a file system
specific flags value which the operations can use to disambiguate between
different handlers; some file systems use that to distinguish the xattr
namespace, for example. In some oprations, it would be useful to also have
access to the handler prefix. To allow that, pass a pointer to the handler
to operations instead of the flags value alone.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull vfs update from Al Viro:
- misc stable fixes
- trivial kernel-doc and comment fixups
- remove never-used block_page_mkwrite() wrapper function, and rename
the function that is _actually_ used to not have double underscores.
* 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs: 9p: cache.h: Add #define of include guard
vfs: remove stale comment in inode_operations
vfs: remove unused wrapper block_page_mkwrite()
binfmt_elf: Correct `arch_check_elf's description
fs: fix writeback.c kernel-doc warnings
fs: fix inode.c kernel-doc warning
fs/pipe.c: return error code rather than 0 in pipe_write()
fs/pipe.c: preserve alloc_file() error code
binfmt_elf: Don't clobber passed executable's file header
FS-Cache: Handle a write to the page immediately beyond the EOF marker
cachefiles: perform test on s_blocksize when opening cache file.
FS-Cache: Don't override netfs's primary_index if registering failed
FS-Cache: Increase reference of parent after registering, netfs success
debugfs: fix refcount imbalance in start_creating
The include file was intended to have an include guard, but the #define
part is missing.
Signed-off-by: Tzvetelin Katchov <katchov@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
new_valid_dev() always returns 1, so the !new_valid_dev() check is not
needed. Remove it.
Signed-off-by: Yaowei Bai <bywxiaobai@163.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge patch-bomb from Andrew Morton:
- inotify tweaks
- some ocfs2 updates (many more are awaiting review)
- various misc bits
- kernel/watchdog.c updates
- Some of mm. I have a huge number of MM patches this time and quite a
lot of it is quite difficult and much will be held over to next time.
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (162 commits)
selftests: vm: add tests for lock on fault
mm: mlock: add mlock flags to enable VM_LOCKONFAULT usage
mm: introduce VM_LOCKONFAULT
mm: mlock: add new mlock system call
mm: mlock: refactor mlock, munlock, and munlockall code
kasan: always taint kernel on report
mm, slub, kasan: enable user tracking by default with KASAN=y
kasan: use IS_ALIGNED in memory_is_poisoned_8()
kasan: Fix a type conversion error
lib: test_kasan: add some testcases
kasan: update reference to kasan prototype repo
kasan: move KASAN_SANITIZE in arch/x86/boot/Makefile
kasan: various fixes in documentation
kasan: update log messages
kasan: accurately determine the type of the bad access
kasan: update reported bug types for kernel memory accesses
kasan: update reported bug types for not user nor kernel memory accesses
mm/kasan: prevent deadlock in kasan reporting
mm/kasan: don't use kasan shadow pointer in generic functions
mm/kasan: MODULE_VADDR is not available on all archs
...
If the remote locking fail, we run a local vfs unlock that should work and
return success to userland when we didn't actually lock at all. We need
to tell the application that tried to lock that it didn't get it, not that
all went well.
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Instead of having users check for FL_POSIX or FL_FLOCK to call the correct
locks API function, use the check within locks_lock_inode_wait(). This
allows for some later cleanup.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
When reading 0 bytes from an empty file on a 9P filesystem, the return
code of read() was not 0 as expected due to an unitialized err variable.
Tested with this simple program:
#include <assert.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
int main(int argc, const char **argv)
{
assert(argc == 2);
char buffer[256];
int fd = open(argv[1], O_RDONLY|O_NOCTTY);
assert(fd >= 0);
assert(read(fd, buffer, 0) == 0);
return 0;
}
Signed-off-by: Vincent Bernat <vincent@bernat.im>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Commit 8a0dc95fd9
("9p: transport API reorganization")
removed Opt_trans in tokens not in enum.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Pull cgroup writeback support from Jens Axboe:
"This is the big pull request for adding cgroup writeback support.
This code has been in development for a long time, and it has been
simmering in for-next for a good chunk of this cycle too. This is one
of those problems that has been talked about for at least half a
decade, finally there's a solution and code to go with it.
Also see last weeks writeup on LWN:
http://lwn.net/Articles/648292/"
* 'for-4.2/writeback' of git://git.kernel.dk/linux-block: (85 commits)
writeback, blkio: add documentation for cgroup writeback support
vfs, writeback: replace FS_CGROUP_WRITEBACK with SB_I_CGROUPWB
writeback: do foreign inode detection iff cgroup writeback is enabled
v9fs: fix error handling in v9fs_session_init()
bdi: fix wrong error return value in cgwb_create()
buffer: remove unusued 'ret' variable
writeback: disassociate inodes from dying bdi_writebacks
writeback: implement foreign cgroup inode bdi_writeback switching
writeback: add lockdep annotation to inode_to_wb()
writeback: use unlocked_inode_to_wb transaction in inode_congested()
writeback: implement unlocked_inode_to_wb transaction and use it for stat updates
writeback: implement [locked_]inode_to_wb_and_lock_list()
writeback: implement foreign cgroup inode detection
writeback: make writeback_control track the inode being written back
writeback: relocate wb[_try]_get(), wb_put(), inode_{attach|detach}_wb()
mm: vmscan: disable memcg direct reclaim stalling if cgroup writeback support is in use
writeback: implement memcg writeback domain based throttling
writeback: reset wb_domain->dirty_limit[_tstmp] when memcg domain size changes
writeback: implement memcg wb_domain
writeback: update wb_over_bg_thresh() to use wb_domain aware operations
...
On failure, v9fs_session_init() returns with the v9fs_session_info
struct partially initialized and expects the caller to invoke
v9fs_session_close() to clean it up; however, it doesn't track whether
the bdi is initialized or not and curiously invokes bdi_destroy() in
both vfs_session_init() failure path too.
A. If v9fs_session_init() fails before the bdi is initialized, the
follow-up v9fs_session_close() will invoke bdi_destroy() on an
uninitialized bdi.
B. If v9fs_session_init() fails after the bdi is initialized,
bdi_destroy() will be called twice on the same bdi - once in the
failure path of v9fs_session_init() and then by
v9fs_session_close().
A is broken no matter what. B used to be okay because bdi_destroy()
allowed being invoked multiple times on the same bdi, which BTW was
broken in its own way - if bdi_destroy() was invoked on an initialiezd
but !registered bdi, it'd fail to free percpu counters. Since
f0054bb1e1 ("writeback: move backing_dev_info->wb_lock and
->worklist into bdi_writeback"), this no longer work - bdi_destroy()
on an initialized but not registered bdi works correctly but multiple
invocations of bdi_destroy() is no longer allowed.
The obvious culprit here is v9fs_session_init()'s odd and broken error
behavior. It should simply clean up after itself on failures. This
patch makes the following updates to v9fs_session_init().
* @rc -> @retval error return propagation removed. It didn't serve
any purpose. Just use @rc.
* Move addition to v9fs_sessionlist to the end of the function so that
incomplete sessions are not put on the list or iterated and error
path doesn't have to worry about it.
* Update error handling so that it cleans up after itself.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
a) instead of storing the symlink body (via nd_set_link()) and returning
an opaque pointer later passed to ->put_link(), ->follow_link() _stores_
that opaque pointer (into void * passed by address by caller) and returns
the symlink body. Returning ERR_PTR() on error, NULL on jump (procfs magic
symlinks) and pointer to symlink body for normal symlinks. Stored pointer
is ignored in all cases except the last one.
Storing NULL for opaque pointer (or not storing it at all) means no call
of ->put_link().
b) the body used to be passed to ->put_link() implicitly (via nameidata).
Now only the opaque pointer is. In the cases when we used the symlink body
to free stuff, ->follow_link() now should store it as opaque pointer in addition
to returning it.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We copy there a kmalloc'ed string and proceed to kfree that string immediately
after that. Easier to just feed that string to nd_set_link() and _not_
kfree it until ->put_link() (which becomes kfree_put_link() in that case).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull fourth vfs update from Al Viro:
"d_inode() annotations from David Howells (sat in for-next since before
the beginning of merge window) + four assorted fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
RCU pathwalk breakage when running into a symlink overmounting something
fix I_DIO_WAKEUP definition
direct-io: only inc/dec inode->i_dio_count for file systems
fs/9p: fix readdir()
VFS: assorted d_backing_inode() annotations
VFS: fs/inode.c helpers: d_inode() annotations
VFS: fs/cachefiles: d_backing_inode() annotations
VFS: fs library helpers: d_inode() annotations
VFS: assorted weird filesystems: d_inode() annotations
VFS: normal filesystems (and lustre): d_inode() annotations
VFS: security/: d_inode() annotations
VFS: security/: d_backing_inode() annotations
VFS: net/: d_inode() annotations
VFS: net/unix: d_backing_inode() annotations
VFS: kernel/: d_inode() annotations
VFS: audit: d_backing_inode() annotations
VFS: Fix up some ->d_inode accesses in the chelsio driver
VFS: Cachefiles should perform fs modifications on the top layer only
VFS: AF_UNIX sockets should call mknod on the top layer only
Al Viro's IOV changes broke 9p readdir() because the new code
didn't abort the read when it returned nothing. The original
code checked if the combined error/length was <= 0 but in the
new code that accidentally got changed to just an error check.
Add back the return from the function when nothing is read.
Cc: Al Viro <viro@zeniv.linux.org.uk>
Fixes: e1200fe68f ("9p: switch p9_client_read() to passing struct iov_iter *")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Some accumulated cleanup patches for kerneldoc and unused variables
as well as some lock bug fixes and adding privateport option for RDMA.
A quick check shows some merge-conflicts versus current-tip on
9p: use unsigned integers for nwqid/count
If you would prefer I can rebase, remerge and fix the patch but didn't
want to do that and look the for-next references.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
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Merge tag 'for-linus-4.1-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs
Pull 9pfs updates from Eric Van Hensbergen:
"Some accumulated cleanup patches for kerneldoc and unused variables as
well as some lock bug fixes and adding privateport option for RDMA"
* tag 'for-linus-4.1-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
net/9p: add a privport option for RDMA transport.
fs/9p: Initialize status in v9fs_file_do_lock.
net/9p: Initialize opts->privport as it should be.
net/9p: use memcpy() instead of snprintf() in p9_mount_tag_show()
9p: use unsigned integers for nwqid/count
9p: do not crash on unknown lock status code
9p: fix error handling in v9fs_file_do_lock
9p: remove unused variable in p9_fd_create()
9p: kerneldoc warning fixes
that's the bulk of filesystem drivers dealing with inodes of their own
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
... returning -E... upon error and amount of data left in iter after
(possible) truncation upon success. Note, that normal case gives
a non-zero (positive) return value, so any tests for != 0 _must_ be
updated.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Conflicts:
fs/ext4/file.c
The rw parameter to direct_IO is redundant with iov_iter->type, and
treated slightly differently just about everywhere it's used: some users
do rw & WRITE, and others do rw == WRITE where they should be doing a
bitwise check. Simplify this with the new iov_iter_rw() helper, which
always returns either READ or WRITE.
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
All places outside of core VFS that checked ->read and ->write for being NULL or
called the methods directly are gone now, so NULL {read,write} with non-NULL
{read,write}_iter will do the right thing in all cases.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
struct kiocb now is a generic I/O container, so move it to fs.h.
Also do a #include diet for aio.h while we're at it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
If p9_client_lock_dotl returns an error, status is possibly never filled
but will be used in the following switch.
Initializing it to P9_LOCK_ERROR makes sur we will return an error and
cleanup (and not hit the default case).
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Current 9p implementation will crash whole system if sees unknown lock
status code. It's trivial target for DOS: 9p server can produce such
code easily.
Let's fallback more gracefully: warning in dmesg + -ENOLCK.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
p9_client_lock_dotl() doesn't set status if p9_client_rpc() fails.
It can lead to 'default:' case in switch below and kernel crashes.
Let's bypass the switch if p9_client_lock_dotl() fails.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
options argument was removed from v9fs_session_info in commit 4b53e4b500
("9p: remove unnecessary v9fses->options which duplicates the mount string")
iov and nr_segs were removed from v9fs_direct_IO
in commit d8d3d94b80
("pass iov_iter to ->direct_IO()")
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: v9fs-developer@lists.sourceforge.net
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Convert the following where appropriate:
(1) S_ISLNK(dentry->d_inode) to d_is_symlink(dentry).
(2) S_ISREG(dentry->d_inode) to d_is_reg(dentry).
(3) S_ISDIR(dentry->d_inode) to d_is_dir(dentry). This is actually more
complicated than it appears as some calls should be converted to
d_can_lookup() instead. The difference is whether the directory in
question is a real dir with a ->lookup op or whether it's a fake dir with
a ->d_automount op.
In some circumstances, we can subsume checks for dentry->d_inode not being
NULL into this, provided we the code isn't in a filesystem that expects
d_inode to be NULL if the dirent really *is* negative (ie. if we're going to
use d_inode() rather than d_backing_inode() to get the inode pointer).
Note that the dentry type field may be set to something other than
DCACHE_MISS_TYPE when d_inode is NULL in the case of unionmount, where the VFS
manages the fall-through from a negative dentry to a lower layer. In such a
case, the dentry type of the negative union dentry is set to the same as the
type of the lower dentry.
However, if you know d_inode is not NULL at the call site, then you can use
the d_is_xxx() functions even in a filesystem.
There is one further complication: a 0,0 chardev dentry may be labelled
DCACHE_WHITEOUT_TYPE rather than DCACHE_SPECIAL_TYPE. Strictly, this was
intended for special directory entry types that don't have attached inodes.
The following perl+coccinelle script was used:
use strict;
my @callers;
open($fd, 'git grep -l \'S_IS[A-Z].*->d_inode\' |') ||
die "Can't grep for S_ISDIR and co. callers";
@callers = <$fd>;
close($fd);
unless (@callers) {
print "No matches\n";
exit(0);
}
my @cocci = (
'@@',
'expression E;',
'@@',
'',
'- S_ISLNK(E->d_inode->i_mode)',
'+ d_is_symlink(E)',
'',
'@@',
'expression E;',
'@@',
'',
'- S_ISDIR(E->d_inode->i_mode)',
'+ d_is_dir(E)',
'',
'@@',
'expression E;',
'@@',
'',
'- S_ISREG(E->d_inode->i_mode)',
'+ d_is_reg(E)' );
my $coccifile = "tmp.sp.cocci";
open($fd, ">$coccifile") || die $coccifile;
print($fd "$_\n") || die $coccifile foreach (@cocci);
close($fd);
foreach my $file (@callers) {
chomp $file;
print "Processing ", $file, "\n";
system("spatch", "--sp-file", $coccifile, $file, "--in-place", "--no-show-diff") == 0 ||
die "spatch failed";
}
[AV: overlayfs parts skipped]
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull backing device changes from Jens Axboe:
"This contains a cleanup of how the backing device is handled, in
preparation for a rework of the life time rules. In this part, the
most important change is to split the unrelated nommu mmap flags from
it, but also removing a backing_dev_info pointer from the
address_space (and inode), and a cleanup of other various minor bits.
Christoph did all the work here, I just fixed an oops with pages that
have a swap backing. Arnd fixed a missing export, and Oleg killed the
lustre backing_dev_info from staging. Last patch was from Al,
unexporting parts that are now no longer needed outside"
* 'for-3.20/bdi' of git://git.kernel.dk/linux-block:
Make super_blocks and sb_lock static
mtd: export new mtd_mmap_capabilities
fs: make inode_to_bdi() handle NULL inode
staging/lustre/llite: get rid of backing_dev_info
fs: remove default_backing_dev_info
fs: don't reassign dirty inodes to default_backing_dev_info
nfs: don't call bdi_unregister
ceph: remove call to bdi_unregister
fs: remove mapping->backing_dev_info
fs: export inode_to_bdi and use it in favor of mapping->backing_dev_info
nilfs2: set up s_bdi like the generic mount_bdev code
block_dev: get bdev inode bdi directly from the block device
block_dev: only write bdev inode on close
fs: introduce f_op->mmap_capabilities for nommu mmap support
fs: kill BDI_CAP_SWAP_BACKED
fs: deduplicate noop_backing_dev_info
Since "BDI: Provide backing device capability information [try #3]" the
backing_dev_info structure also provides flags for the kind of mmap
operation available in a nommu environment, which is entirely unrelated
to it's original purpose.
Introduce a new nommu-only file operation to provide this information to
the nommu mmap code instead. Splitting this from the backing_dev_info
structure allows to remove lots of backing_dev_info instance that aren't
otherwise needed, and entirely gets rid of the concept of providing a
backing_dev_info for a character device. It also removes the need for
the mtd_inodefs filesystem.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tejun Heo <tj@kernel.org>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
