Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

tracepoints are evil, exhibit #6969...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Beginning to introduce those.  Just the callers for now, and it's
clumsier than it'll eventually become; once we finish converting
aio_read and aio_write instances, the things will get nicer.

For now, these guys are in parallel to ->aio_read() and ->aio_write();
they take iocb and iov_iter, with everything in iov_iter already
validated.  File offset is passed in iocb->ki_pos, iov/nr_segs -
in iov_iter.

Main concerns in that series are stack footprint and ability to
split the damn thing cleanly.

[fix from Peter Ujfalusi <peter.ujfalusi@ti.com> folded]
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Since we are about to introduce new methods (read_iter/write_iter), the
tests in a bunch of places would have to grow inconveniently.  Check
once (at open() time) and store results in ->f_mode as FMODE_CAN_READ
and FMODE_CAN_WRITE resp.  It might end up being a temporary measure -
once everything switches from ->aio_{read,write} to ->{read,write}_iter
it might make sense to return to open-coded checks.  We'll see...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

pos is redundant (it's iocb->ki_pos), and iov/nr_segs/count are taken
care of by lifting iov_iter into the caller.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Now It Can Be Done(tm) - we don't need to do iov_shorten() in
generic_file_direct_write() anymore, now that all ->direct_IO()
instances are converted to proper iov_iter methods and honour
iter->count and iter->iov_offset properly.

Get rid of count/ocount arguments of generic_file_direct_write(),
while we are at it.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

... and don't open-code iov_iter_alignment() there
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

same as iov_iter_get_pages(), except that pages array is allocated
(kmalloc if possible, vmalloc if that fails) and left for caller to
free.  Lustre and NFS ->direct_IO() switched to it.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

counts the pages covered by iov_iter, up to given limit.
do_block_direct_io() and fuse_iter_npages() switched to
it.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

... to fuse_direct_{read,write}().  ->direct_IO() path uses the
iov_iter passed by the caller instead.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

iov_iter_get_pages(iter, pages, maxsize, &start) grabs references pinning
the pages of up to maxsize of (contiguous) data from iter.  Returns the
amount of memory grabbed or -error.  In case of success, the requested
area begins at offset start in pages[0] and runs through pages[1], etc.
Less than requested amount might be returned - either because the contiguous
area in the beginning of iterator is smaller than requested, or because
the kernel failed to pin that many pages.

direct-io.c switched to using iov_iter_get_pages()
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

For now, just use the same thing we pass to ->direct_IO() - it's all
iovec-based at the moment.  Pass it explicitly to iov_iter_init() and
account for kvec vs. iovec in there, by the same kludge NFS ->direct_IO()
uses.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

iov_iter-using variant of generic_file_aio_read().  Some callers
converted.  Note that it's still not quite there for use as ->read_iter() -
we depend on having zero iter->iov_offset in O_DIRECT case.  Fortunately,
that's true for all converted callers (and for generic_file_aio_read() itself).
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

returns the value aligned as badly as the worst remaining segment
in iov_iter is.  Use instead of open-coded equivalents.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

all callers have iov_length(iter->iov, iter->nr_segs) == iov_iter_count(iter)
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

unmodified, for now
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

all callers of ->aio_read() and ->aio_write() have iov/nr_segs already
checked - generic_segment_checks() done after that is just an odd way
to spell iov_length().
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

all callers can use copy_page_from_iter() and it actually simplifies
them.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Commit 842a859d ("affs: use ->kill_sb() to simplify ->put_super()
and failure exits of ->mount()") adds .kill_sb which frees sbi but
doesn't remove sbi free in case of parse_options error causing double
free+random crash.
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>	[3.14.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

On 64-bit systems, O_LARGEFILE is automatically added to flags inside
the open() syscall (also openat(), blkdev_open(), etc).  Userspace
therefore defines O_LARGEFILE to be 0 - you can use it, but it's a
no-op.  Everything should be O_LARGEFILE by default.

But: when fanotify does create_fd() it uses dentry_open(), which skips
all that.  And userspace can't set O_LARGEFILE in fanotify_init()
because it's defined to 0.  So if fanotify gets an event regarding a
large file, the read() will just fail with -EOVERFLOW.

This patch adds O_LARGEFILE to fanotify_init()'s event_f_flags on 64-bit
systems, using the same test as open()/openat()/etc.

Addresses https://bugzilla.redhat.com/show_bug.cgi?id=696821Signed-off-by: NWill Woods <wwoods@redhat.com>
Acked-by: NEric Paris <eparis@redhat.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

autofs needs to be able to see private data dentry flags for its dentrys
that are being created but not yet hashed and for its dentrys that have
been rmdir()ed but not yet freed.  It needs to do this so it can block
processes in these states until a status has been returned to indicate
the given operation is complete.

It does this by keeping two lists, active and expring, of dentrys in
this state and uses ->d_release() to keep them stable while it checks
the reference count to determine if they should be used.

But with the recent lockref changes dentrys being freed sometimes don't
transition to a reference count of 0 before being freed so autofs can
occassionally use a dentry that is invalid which can lead to a panic.
Signed-off-by: NIan Kent <raven@themaw.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently, I am seeing the following when I `mount -t hugetlbfs /none
/dev/hugetlbfs`, and then simply do a `ls /dev/hugetlbfs`.  I think it's
related to the fact that hugetlbfs is properly not correctly setting
itself up in this state?:

  Unable to handle kernel paging request for data at address 0x00000031
  Faulting instruction address: 0xc000000000245710
  Oops: Kernel access of bad area, sig: 11 [#1]
  SMP NR_CPUS=2048 NUMA pSeries
  ....

In KVM guests on Power, in a guest not backed by hugepages, we see the
following:

  AnonHugePages:         0 kB
  HugePages_Total:       0
  HugePages_Free:        0
  HugePages_Rsvd:        0
  HugePages_Surp:        0
  Hugepagesize:         64 kB

HPAGE_SHIFT == 0 in this configuration, which indicates that hugepages
are not supported at boot-time, but this is only checked in
hugetlb_init().  Extract the check to a helper function, and use it in a
few relevant places.

This does make hugetlbfs not supported (not registered at all) in this
environment.  I believe this is fine, as there are no valid hugepages
and that won't change at runtime.

[akpm@linux-foundation.org: use pr_info(), per Mel]
[akpm@linux-foundation.org: fix build when HPAGE_SHIFT is undefined]
Signed-off-by: NNishanth Aravamudan <nacc@linux.vnet.ibm.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: NMel Gorman <mgorman@suse.de>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Various filesystems don't bother checking for a NULL ACL in
posix_acl_equiv_mode, and thus can dereference a NULL pointer when it
gets passed one. This usually happens from the NFS server, as the ACL tools
never pass a NULL ACL, but instead of one representing the mode bits.

Instead of adding boilerplat to all filesystems put this check into one place,
which will allow us to remove the check from other filesystems as well later
on.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reported-by: NBen Greear <greearb@candelatech.com>
Reported-by: Marco Munderloh <munderl@tnt.uni-hannover.de>,
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Dan's "smatch" checker found out that there was a bug in the error path of the
'ubifs_remount_rw()' function. Instead of jumping to the "out" label which
cleans-things up, we just returned.

This patch fixes the problem.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>