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

New method - ->iterate(file, ctx).  That's the replacement for ->readdir();
it takes callback from ctx->actor, uses ctx->pos instead of file->f_pos and
calls dir_emit(ctx, ...) instead of filldir(data, ...).  It does *not*
update file->f_pos (or look at it, for that matter); iterate_dir() does the
update.

Note that dir_emit() takes the offset from ctx->pos (and eventually
filldir_t will lose that argument).
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

iterate_dir(): new helper, replacing vfs_readdir().

struct dir_context: contains the readdir callback (and will get more stuff
in it), embedded into whatever data that callback wants to deal with;
eventually, we'll be passing it to ->readdir() replacement instead of
(data,filldir) pair.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Faster kernel compiles by way of fewer unnecessary includes.

[akpm@linux-foundation.org: fix fallout]
[akpm@linux-foundation.org: fix build]
Signed-off-by: NKent Overstreet <koverstreet@google.com>
Cc: Zach Brown <zab@redhat.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Reviewed-by: N"Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/compat.c doesn't need it anymore, so let's just move the remaining
contents (two typedefs) into fs/read_write.c
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

... and take to fs/read_write.c
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

Looking at mm/process_vm_access.c:process_vm_rw() and comparing it to
compat_process_vm_rw() shows that the compatibility code requires an
explicit "access_ok()" check before calling
compat_rw_copy_check_uvector(). The same difference seems to appear when
we compare fs/read_write.c:do_readv_writev() to
fs/compat.c:compat_do_readv_writev().

This subtle difference between the compat and non-compat requirements
should probably be debated, as it seems to be error-prone. In fact,
there are two others sites that use this function in the Linux kernel,
and they both seem to get it wrong:

Now shifting our attention to fs/aio.c, we see that aio_setup_iocb()
also ends up calling compat_rw_copy_check_uvector() through
aio_setup_vectored_rw(). Unfortunately, the access_ok() check appears to
be missing. Same situation for
security/keys/compat.c:compat_keyctl_instantiate_key_iov().

I propose that we add the access_ok() check directly into
compat_rw_copy_check_uvector(), so callers don't have to worry about it,
and it therefore makes the compat call code similar to its non-compat
counterpart. Place the access_ok() check in the same location where
copy_from_user() can trigger a -EFAULT error in the non-compat code, so
the ABI behaviors are alike on both compat and non-compat.

While we are here, fix compat_do_readv_writev() so it checks for
compat_rw_copy_check_uvector() negative return values.

And also, fix a memory leak in compat_keyctl_instantiate_key_iov() error
handling.
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Acked-by: NAl Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NMathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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>

... and move them over to fs/timerfd.c.  Cleaner and easier
that way...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

getname() is intended to copy pathname strings from userspace into a
kernel buffer. The result is just a string in kernel space. It would
however be quite helpful to be able to attach some ancillary info to
the string.

For instance, we could attach some audit-related info to reduce the
amount of audit-related processing needed. When auditing is enabled,
we could also call getname() on the string more than once and not
need to recopy it from userspace.

This patchset converts the getname()/putname() interfaces to return
a struct instead of a string. For now, the struct just tracks the
string in kernel space and the original userland pointer for it.

Later, we'll add other information to the struct as it becomes
convenient.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

This function is used by sparc, powerpc and arm64 for compat support.
The patch adds a generic implementation which calls do_sendfile()
directly and avoids set_fs().

The sparc architecture has wrappers for the sign extensions while
powerpc relies on the compiler to do the this. The patch adds wrappers
for powerpc to handle the u32->int type conversion.

compat_sys_sendfile64() can be replaced by a sys_sendfile() call since
compat_loff_t has the same size as off_t on a 64-bit system.

On powerpc, the patch also changes the 64-bit sendfile call from
sys_sendile64 to sys_sendfile.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

compat_sys_{read,write}v() need the same "pass a copy of file->f_pos" thing
as sys_{read,write}{,v}().
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Everyone either defines it in arch thread_info.h or has TIF_RESTORE_SIGMASK
and picks default set_restore_sigmask() in linux/thread_info.h.  Kill the
ifdefs, slap #error in linux/thread_info.h to catch breakage when new ones
get merged.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

A cleanup of rw_copy_check_uvector and compat_rw_copy_check_uvector after
changes made to support CMA in an earlier patch.

Rather than having an additional check_access parameter to these
functions, the first paramater type is overloaded to allow the caller to
specify CHECK_IOVEC_ONLY which means check that the contents of the iovec
are valid, but do not check the memory that they point to.  This is used
by process_vm_readv/writev where we need to validate that a iovec passed
to the syscall is valid but do not want to check the memory that it points
to at this point because it refers to an address space in another process.
Signed-off-by: NChris Yeoh <yeohc@au1.ibm.com>
Reviewed-by: NOleg Nesterov <oleg@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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

- Store uids and gids with kuid_t and kgid_t in struct kstat
- Convert uid and gids to userspace usable values with
  from_kuid and from_kgid
Acked-by: NSerge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>

For files only using THIS_MODULE and/or EXPORT_SYMBOL, map
them onto including export.h -- or if the file isn't even
using those, then just delete the include.  Fix up any implicit
include dependencies that were being masked by module.h along
the way.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

For 32-bit ABIs which have real 64-bit registers, we don't want to
break the position argument into two.  However, we still need compat
support to deal with 32-bit pointers, so we can't just use
sys_p{read,write} directly.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Massaged cp_compat_stat() into form closer to cp_new_stat(); the only
real issue had been in handling of st_nlink overflows - native 32bit
stat(2) returns -EOVERFLOW in such situations, compat one silently
loses upper bits.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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

... and bury user_get_super()/statfs_by_dentry() - they are
purely internal now.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

The basic idea behind cross memory attach is to allow MPI programs doing
intra-node communication to do a single copy of the message rather than a
double copy of the message via shared memory.

The following patch attempts to achieve this by allowing a destination
process, given an address and size from a source process, to copy memory
directly from the source process into its own address space via a system
call.  There is also a symmetrical ability to copy from the current
process's address space into a destination process's address space.

- Use of /proc/pid/mem has been considered, but there are issues with
  using it:
  - Does not allow for specifying iovecs for both src and dest, assuming
    preadv or pwritev was implemented either the area read from or
  written to would need to be contiguous.
  - Currently mem_read allows only processes who are currently
  ptrace'ing the target and are still able to ptrace the target to read
  from the target. This check could possibly be moved to the open call,
  but its not clear exactly what race this restriction is stopping
  (reason  appears to have been lost)
  - Having to send the fd of /proc/self/mem via SCM_RIGHTS on unix
  domain socket is a bit ugly from a userspace point of view,
  especially when you may have hundreds if not (eventually) thousands
  of processes  that all need to do this with each other
  - Doesn't allow for some future use of the interface we would like to
  consider adding in the future (see below)
  - Interestingly reading from /proc/pid/mem currently actually
  involves two copies! (But this could be fixed pretty easily)

As mentioned previously use of vmsplice instead was considered, but has
problems.  Since you need the reader and writer working co-operatively if
the pipe is not drained then you block.  Which requires some wrapping to
do non blocking on the send side or polling on the receive.  In all to all
communication it requires ordering otherwise you can deadlock.  And in the
example of many MPI tasks writing to one MPI task vmsplice serialises the
copying.

There are some cases of MPI collectives where even a single copy interface
does not get us the performance gain we could.  For example in an
MPI_Reduce rather than copy the data from the source we would like to
instead use it directly in a mathops (say the reduce is doing a sum) as
this would save us doing a copy.  We don't need to keep a copy of the data
from the source.  I haven't implemented this, but I think this interface
could in the future do all this through the use of the flags - eg could
specify the math operation and type and the kernel rather than just
copying the data would apply the specified operation between the source
and destination and store it in the destination.

Although we don't have a "second user" of the interface (though I've had
some nibbles from people who may be interested in using it for intra
process messaging which is not MPI).  This interface is something which
hardware vendors are already doing for their custom drivers to implement
fast local communication.  And so in addition to this being useful for
OpenMPI it would mean the driver maintainers don't have to fix things up
when the mm changes.

There was some discussion about how much faster a true zero copy would
go. Here's a link back to the email with some testing I did on that:

http://marc.info/?l=linux-mm&m=130105930902915&w=2

There is a basic man page for the proposed interface here:

http://ozlabs.org/~cyeoh/cma/process_vm_readv.txt

This has been implemented for x86 and powerpc, other architecture should
mainly (I think) just need to add syscall numbers for the process_vm_readv
and process_vm_writev. There are 32 bit compatibility versions for
64-bit kernels.

For arch maintainers there are some simple tests to be able to quickly
verify that the syscalls are working correctly here:

http://ozlabs.org/~cyeoh/cma/cma-test-20110718.tgzSigned-off-by: NChris Yeoh <yeohc@au1.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: <linux-man@vger.kernel.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This was found by inspection while tracking a similar
bug in compat_statfs64, that has been fixed in mainline
since decemeber.

- This fixes a bug where not all of the f_spare fields
  were cleared on mips and s390.
- Add the f_flags field to struct compat_statfs
- Copy f_flags to userspace in case someone cares.
- Use __clear_user to copy the f_spare field to userspace
  to ensure that all of the elements of f_spare are cleared.
  On some architectures f_spare is has 5 ints and on some
  architectures f_spare only has 4 ints.  Which makes
  the previous technique of clearing each int individually
  broken.

I don't expect anyone actually uses the old statfs system
call anymore but if they do let them benefit from having
the compat and the native version working the same.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>

We don't need this any more.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The nfsservctl system call is now gone, so we should remove all
linkage for it.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

As promised in feature-removal-schedule.txt it is time to
remove the nfsctl system call.

Userspace has perferred to not use this call throughout 2.6 and it has been
excluded in the default configuration since 2.6.36 (9 months ago).

So this patch removes all the code that was being compiled out.

There are still references to sys_nfsctl in various arch systemcall tables
and related code.  These should be cleaned out too, probably in the next
merge window.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Add the appropriate members into struct user_arg_ptr and teach
get_user_arg_ptr() to handle is_compat = T case correctly.

This allows us to remove the compat_do_execve() code from fs/compat.c
and reimplement compat_do_execve() as the trivial wrapper on top of
do_execve_common(is_compat => true).

In fact, this fixes another (minor) bug. "compat_uptr_t str" can
overflow after "str += len" in compat_copy_strings() if a 64bit
application execs via sys32_execve().

Unexport acct_arg_size() and get_arg_page(), fs/compat.c doesn't
need them any longer.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Reviewed-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Tested-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>

Remove the leftover from the commit 8ff3e8e8 ("select:
switch select() and poll() over to hrtimers").
Signed-off-by: NNamhyung Kim <namhyung@gmail.com>
Acked-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

[AV: duplicate of open() guts removed; file_open_root() used instead]
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

New helpers: user_statfs() and fd_statfs(), taking userland pathname and
descriptor resp. and filling struct kstatfs.  Syscalls of statfs family
(native, compat and foreign - osf and hpux on alpha and parisc resp.)
switched to those.  Removes some boilerplate code, simplifies cleanup
on errors...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Fix for a dumb preadv()/pwritev() compat bug - unlike the native
variants, the compat_...  ones forget to check FMODE_P{READ,WRITE}, so
e.g.  on pipe the native preadv() will fail with -ESPIPE and compat one
will act as readv() and succeed.

Not critical, but it's a clear bug with trivial fix, so IMO it's OK for
-final.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix for a dumb preadv()/pwritev() compat bug - unlike the native
variants, compat_... ones forget to check FMODE_P{READ,WRITE}, so e.g.
on pipe the native preadv() will fail with -ESPIPE and compat one will
act as readv() and succeed.  Not critical, but it's a clear bug with trivial
fix.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

f_flags and f_spare fields were not copied to userspace when
compat_sys_[f]statfs64 called.
Signed-off-by: NNamhyung Kim <namhyung@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

The commit 7ed1ee61 ("Take statfs variants to fs/statfs.c")
separates out statfs syscalls from fs/open.c. Thus the comment
should be changed also.
Signed-off-by: NNamhyung Kim <namhyung@gmail.com>
Cc: Jiri Kosina <trivial@kernel.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>