If we request reading or writing on a file that needs to be
reopened, it causes the deadlock: we are already holding rw
semaphore for reading and then we try to acquire it for writing
in cifs_relock_file. Fix this by acquiring the semaphore for
reading in cifs_relock_file due to we don't make any changes in
locks and don't need a write access.
CC: <stable@vger.kernel.org>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
This is a follow-on patch for 8/8 patch from the durable handles
series. It fixes the problem when durable file handle timeout
expired on the server and reopen returns -ENOENT for such files.
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
On reconnects, we need to reopen file and then obtain all byte-range
locks held by the client. SMB2 protocol provides feature to make
this process atomic by reconnecting to the same file handle
with all it's byte-range locks. This patch adds this capability
for SMB2 shares.
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steven French <steven@steven-GA-970A-DS3.(none)>
Pull second set of VFS changes from Al Viro:
"Assorted f_pos race fixes, making do_splice_direct() safe to call with
i_mutex on parent, O_TMPFILE support, Jeff's locks.c series,
->d_hash/->d_compare calling conventions changes from Linus, misc
stuff all over the place."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
Document ->tmpfile()
ext4: ->tmpfile() support
vfs: export lseek_execute() to modules
lseek_execute() doesn't need an inode passed to it
block_dev: switch to fixed_size_llseek()
cpqphp_sysfs: switch to fixed_size_llseek()
tile-srom: switch to fixed_size_llseek()
proc_powerpc: switch to fixed_size_llseek()
ubi/cdev: switch to fixed_size_llseek()
pci/proc: switch to fixed_size_llseek()
isapnp: switch to fixed_size_llseek()
lpfc: switch to fixed_size_llseek()
locks: give the blocked_hash its own spinlock
locks: add a new "lm_owner_key" lock operation
locks: turn the blocked_list into a hashtable
locks: convert fl_link to a hlist_node
locks: avoid taking global lock if possible when waking up blocked waiters
locks: protect most of the file_lock handling with i_lock
locks: encapsulate the fl_link list handling
locks: make "added" in __posix_lock_file a bool
...
Having a global lock that protects all of this code is a clear
scalability problem. Instead of doing that, move most of the code to be
protected by the i_lock instead. The exceptions are the global lists
that the ->fl_link sits on, and the ->fl_block list.
->fl_link is what connects these structures to the
global lists, so we must ensure that we hold those locks when iterating
over or updating these lists.
Furthermore, sound deadlock detection requires that we hold the
blocked_list state steady while checking for loops. We also must ensure
that the search and update to the list are atomic.
For the checking and insertion side of the blocked_list, push the
acquisition of the global lock into __posix_lock_file and ensure that
checking and update of the blocked_list is done without dropping the
lock in between.
On the removal side, when waking up blocked lock waiters, take the
global lock before walking the blocked list and dequeue the waiters from
the global list prior to removal from the fl_block list.
With this, deadlock detection should be race free while we minimize
excessive file_lock_lock thrashing.
Finally, in order to avoid a lock inversion problem when handling
/proc/locks output we must ensure that manipulations of the fl_block
list are also protected by the file_lock_lock.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
commit 66189be74 (CIFS: Fix VFS lock usage for oplocked files) exported
the locks_delete_block symbol. There's already an exported helper
function that provides this capability however, so make cifs use that
instead and turn locks_delete_block back into a static function.
Note that if fl->fl_next == NULL then this lock has already been through
locks_delete_block(), so we should be OK to ignore an ENOENT error here
and simply not retry the lock.
Cc: Pavel Shilovsky <piastryyy@gmail.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Currently there is no way to truncate partial page where the end
truncate point is not at the end of the page. This is because it was not
needed and the functionality was enough for file system truncate
operation to work properly. However more file systems now support punch
hole feature and it can benefit from mm supporting truncating page just
up to the certain point.
Specifically, with this functionality truncate_inode_pages_range() can
be changed so it supports truncating partial page at the end of the
range (currently it will BUG_ON() if 'end' is not at the end of the
page).
This commit changes the invalidatepage() address space operation
prototype to accept range to be invalidated and update all the instances
for it.
We also change the block_invalidatepage() in the same way and actually
make a use of the new length argument implementing range invalidation.
Actual file system implementations will follow except the file systems
where the changes are really simple and should not change the behaviour
in any way .Implementation for truncate_page_range() which will be able
to accept page unaligned ranges will follow as well.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Hugh Dickins <hughd@google.com>
It's not obvious from reading the macro names that these macros
are for debugging. Convert the names to a single more typical
kernel style cifs_dbg macro.
cERROR(1, ...) -> cifs_dbg(VFS, ...)
cFYI(1, ...) -> cifs_dbg(FYI, ...)
cFYI(DBG2, ...) -> cifs_dbg(NOISY, ...)
Move the terminating format newline from the macro to the call site.
Add CONFIG_CIFS_DEBUG function cifs_vfs_err to emit the
"CIFS VFS: " prefix for VFS messages.
Size is reduced ~ 1% when CONFIG_CIFS_DEBUG is set (default y)
$ size fs/cifs/cifs.ko*
text data bss dec hex filename
265245 2525 132 267902 4167e fs/cifs/cifs.ko.new
268359 2525 132 271016 422a8 fs/cifs/cifs.ko.old
Other miscellaneous changes around these conversions:
o Miscellaneous typo fixes
o Add terminating \n's to almost all formats and remove them
from the macros to be more kernel style like. A few formats
previously had defective \n's
o Remove unnecessary OOM messages as kmalloc() calls dump_stack
o Coalesce formats to make grep easier,
added missing spaces when coalescing formats
o Use %s, __func__ instead of embedded function name
o Removed unnecessary "cifs: " prefixes
o Convert kzalloc with multiply to kcalloc
o Remove unused cifswarn macro
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
cifsFileInfo objects hold references to dentries and it is possible that
these will still be around in workqueues when VFS decides to kill super
block during unmount.
This results in panics like this one:
BUG: Dentry ffff88001f5e76c0{i=66b4a,n=1M-2} still in use (1) [unmount of cifs cifs]
------------[ cut here ]------------
kernel BUG at fs/dcache.c:943!
[..]
Process umount (pid: 1781, threadinfo ffff88003d6e8000, task ffff880035eeaec0)
[..]
Call Trace:
[<ffffffff811b44f3>] shrink_dcache_for_umount+0x33/0x60
[<ffffffff8119f7fc>] generic_shutdown_super+0x2c/0xe0
[<ffffffff8119f946>] kill_anon_super+0x16/0x30
[<ffffffffa036623a>] cifs_kill_sb+0x1a/0x30 [cifs]
[<ffffffff8119fcc7>] deactivate_locked_super+0x57/0x80
[<ffffffff811a085e>] deactivate_super+0x4e/0x70
[<ffffffff811bb417>] mntput_no_expire+0xd7/0x130
[<ffffffff811bc30c>] sys_umount+0x9c/0x3c0
[<ffffffff81657c19>] system_call_fastpath+0x16/0x1b
Fix this by making each cifsFileInfo object hold a reference to cifs
super block, which implicitly keeps VFS super block around as well.
Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Cc: <stable@vger.kernel.org>
Reported-and-Tested-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Samba rejected libreoffice's attempt to open a file with illegal
O_EXCL (without O_CREAT). Mask this flag off (as the local
linux file system case does) for this case, so that we
don't have disable Unix Extensions unnecessarily due to
the Samba error (Samba server is also being fixed).
See https://bugzilla.samba.org/show_bug.cgi?id=9519
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Pull vfs pile (part one) from Al Viro:
"Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent
locking violations, etc.
The most visible changes here are death of FS_REVAL_DOT (replaced with
"has ->d_weak_revalidate()") and a new helper getting from struct file
to inode. Some bits of preparation to xattr method interface changes.
Misc patches by various people sent this cycle *and* ocfs2 fixes from
several cycles ago that should've been upstream right then.
PS: the next vfs pile will be xattr stuff."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
saner proc_get_inode() calling conventions
proc: avoid extra pde_put() in proc_fill_super()
fs: change return values from -EACCES to -EPERM
fs/exec.c: make bprm_mm_init() static
ocfs2/dlm: use GFP_ATOMIC inside a spin_lock
ocfs2: fix possible use-after-free with AIO
ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path
get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
target: writev() on single-element vector is pointless
export kernel_write(), convert open-coded instances
fs: encode_fh: return FILEID_INVALID if invalid fid_type
kill f_vfsmnt
vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
nfsd: handle vfs_getattr errors in acl protocol
switch vfs_getattr() to struct path
default SET_PERSONALITY() in linux/elf.h
ceph: prepopulate inodes only when request is aborted
d_hash_and_lookup(): export, switch open-coded instances
9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate()
9p: split dropping the acls from v9fs_set_create_acl()
...
Pull user namespace and namespace infrastructure changes from Eric W Biederman:
"This set of changes starts with a few small enhnacements to the user
namespace. reboot support, allowing more arbitrary mappings, and
support for mounting devpts, ramfs, tmpfs, and mqueuefs as just the
user namespace root.
I do my best to document that if you care about limiting your
unprivileged users that when you have the user namespace support
enabled you will need to enable memory control groups.
There is a minor bug fix to prevent overflowing the stack if someone
creates way too many user namespaces.
The bulk of the changes are a continuation of the kuid/kgid push down
work through the filesystems. These changes make using uids and gids
typesafe which ensures that these filesystems are safe to use when
multiple user namespaces are in use. The filesystems converted for
3.9 are ceph, 9p, afs, ocfs2, gfs2, ncpfs, nfs, nfsd, and cifs. The
changes for these filesystems were a little more involved so I split
the changes into smaller hopefully obviously correct changes.
XFS is the only filesystem that remains. I was hoping I could get
that in this release so that user namespace support would be enabled
with an allyesconfig or an allmodconfig but it looks like the xfs
changes need another couple of days before it they are ready."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (93 commits)
cifs: Enable building with user namespaces enabled.
cifs: Convert struct cifs_ses to use a kuid_t and a kgid_t
cifs: Convert struct cifs_sb_info to use kuids and kgids
cifs: Modify struct smb_vol to use kuids and kgids
cifs: Convert struct cifsFileInfo to use a kuid
cifs: Convert struct cifs_fattr to use kuid and kgids
cifs: Convert struct tcon_link to use a kuid.
cifs: Modify struct cifs_unix_set_info_args to hold a kuid_t and a kgid_t
cifs: Convert from a kuid before printing current_fsuid
cifs: Use kuids and kgids SID to uid/gid mapping
cifs: Pass GLOBAL_ROOT_UID and GLOBAL_ROOT_GID to keyring_alloc
cifs: Use BUILD_BUG_ON to validate uids and gids are the same size
cifs: Override unmappable incoming uids and gids
nfsd: Enable building with user namespaces enabled.
nfsd: Properly compare and initialize kuids and kgids
nfsd: Store ex_anon_uid and ex_anon_gid as kuids and kgids
nfsd: Modify nfsd4_cb_sec to use kuids and kgids
nfsd: Handle kuids and kgids in the nfs4acl to posix_acl conversion
nfsd: Convert nfsxdr to use kuids and kgids
nfsd: Convert nfs3xdr to use kuids and kgids
...
Use INVALID_UID and INVALID_GID instead of NO_CHANGE_64 to indicate
the value should not be changed.
In cifs_fill_unix_set_info convert from kuids and kgids into uids and
gids that will fit in FILE_UNIX_BASIC_INFO.
Cc: Steve French <smfrench@gmail.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
If we have mandatory byte-range locks on a file we can't cache reads
because pagereading may have conflicts with these locks on the server.
That's why we should allow level2 oplocks for files without mandatory
locks only.
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
If we have a read oplock and set a read lock in it, we can't write to the
locked area - so, filemap_fdatawrite may fail with a no information for a
userspace application even if we request a write to non-locked area. Fix
this by writing directly to the server and then breaking oplock level from
level2 to None.
Also remove CONFIG_CIFS_SMB2 ifdefs because it's suitable for both CIFS
and SMB2 protocols.
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
that solution has data races and can end up two identical writes to the
server: when clientCanCacheAll value can be changed during the execution
of __generic_file_aio_write.
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
If we have a read oplock and set a read lock in it, we can't write to the
locked area - so, filemap_fdatawrite may fail with a no information for a
userspace application even if we request a write to non-locked area. Fix
this by populating the page cache without marking affected pages dirty
after a successful write directly to the server.
Also remove CONFIG_CIFS_SMB2 ifdefs because it's suitable for both CIFS
and SMB2 protocols.
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
by using cifs_invalidate_mapping rather than invalidate_remote_inode
in cifs_oplock_break - this invalidates all inode pages and resets
fscache cookies.
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
We don't need to permit a write to the area locked with a read lock
by any process including the process that issues the write.
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
If we netogiate mandatory locking style, have a read lock and try
to set a write lock we end up with a write lock in vfs cache and
no lock in cifs lock cache - that's wrong. Fix it by returning
from cifs_setlk immediately if a error occurs during setting a lock.
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
that reacquires byte-range locks when a file is reopened.
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <smfrench@gmail.com>
Commit eddb079deb created a regression in the writepages codepath.
Previously, whenever it needed to check the size of the file, it did so
by consulting the inode->i_size field directly. With that patch, the
i_size was fetched once on entry into the writepages code and that value
was used henceforth.
If the file is changing size though (for instance, if someone is writing
to it or has truncated it), then that value is likely to be wrong. This
can lead to data corruption. Pages past the EOF at the time that the
writepages call was issued may be silently dropped and ignored because
cifs_writepages wrongly assumes that the file must have been truncated
in the interim.
Fix cifs_writepages to properly fetch the size from the inode->i_size
field instead to properly account for this possibility.
Original bug report is here:
https://bugzilla.kernel.org/show_bug.cgi?id=50991
Reported-and-Tested-by: Maxim Britov <ungifted01@gmail.com>
Reviewed-by: Suresh Jayaraman <sjayaraman@suse.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Move actual pte filling for non-linear file mappings into the new special
vma operation: ->remap_pages().
Filesystems must implement this method to get non-linear mapping support,
if it uses filemap_fault() then generic_file_remap_pages() can be used.
Now device drivers can implement this method and obtain nonlinear vma support.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com> #arch/tile
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
FL_CLOSE is quite common when you close a file on which you hold a
lock. The spurious "Unknown lock flags" message in cFYI is
confusing in this case.
Reported-by: Alexander Bokovoy <abokovoy@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Now we walk though cifsFileInfo's list for every incoming lease
break and look for an equivalent there. That approach misses lease
breaks that come just after an open response - we don't have time
to populate new cifsFileInfo structure to the list. Fix this by
adding new list of pending opens and look for a lease there if we
didn't find it in the list of cifsFileInfo structures.
Signed-off-by: Pavel Shilovsky <pshilovsky@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
When we have a file opened with read oplock and we are writing a data
to this file, we need to store the data in the cache and then send to
the server to ensure that the next read operation will get a coherent
data.
Also mark it as CONFIG_CIFS_SMB2 because it's more suitable for SMB2
code but can fix some CIFS problems too (when server delays sending
an oplock break after a write request). We can drop this ifdefs
dependence in future.
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Currently CIFS code accept read/write ops on mandatory locked area
when two processes use the same file descriptor - it's wrong.
Fix this by serializing io and brlock operations on the inode.
Signed-off-by: Pavel Shilovsky <pshilovsky@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
and allow several processes to walk through the lock list and read
can_cache_brlcks value if they are not going to modify them.
Signed-off-by: Pavel Shilovsky <pshilovsky@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Now we need to lock/unlock a spinlock while processing brlock ops
on the inode. Move brlocks of a fid to a separate list and attach
all such lists to the inode. This let us not hold a spinlock.
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Replace the "marshal_iov" function with a "read_into_pages" function.
That function will copy the read data off the socket and into the
pages array, kmapping and reading pages one at a time.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
We'll need an array to put into a smb_rqst, so convert this into an array
instead of (ab)using the lru list_head.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Eventually, we're going to want to append a list of pages to
cifs_readdata instead of a list of kvecs. To prepare for that, turn
the kvec array allocation into a separate one and just keep a
pointer to it in the readdata.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
