fork: report pid reservation failure properly

copy_process will report any failure in alloc_pid as ENOMEM currently
which is misleading because the pid allocation might fail not only when
the memory is short but also when the pid space is consumed already.

The current man page even mentions this case:

: EAGAIN
:
:       A system-imposed limit on the number of threads was encountered.
:       There are a number of limits that may trigger this error: the
:       RLIMIT_NPROC soft resource limit (set via setrlimit(2)), which
:       limits the number of processes and threads for a real user ID, was
:       reached; the kernel's system-wide limit on the number of processes
:       and threads, /proc/sys/kernel/threads-max, was reached (see
:       proc(5)); or the maximum number of PIDs, /proc/sys/kernel/pid_max,
:       was reached (see proc(5)).

so the current behavior is also incorrect wrt.  documentation.  POSIX man
page also suggest returing EAGAIN when the process count limit is reached.

This patch simply propagates error code from alloc_pid and makes sure we
return -EAGAIN due to reservation failure.  This will make behavior of
fork closer to both our documentation and POSIX.

alloc_pid might alsoo fail when the reaper in the pid namespace is dead
(the namespace basically disallows all new processes) and there is no
good error code which would match documented ones. We have traditionally
returned ENOMEM for this case which is misleading as well but as per
Eric W. Biederman this behavior is documented in man pid_namespaces(7)

: If the "init" process of a PID namespace terminates, the kernel
: terminates all of the processes in the namespace via a SIGKILL signal.
: This behavior reflects the fact that the "init" process is essential for
: the correct operation of a PID namespace.  In this case, a subsequent
: fork(2) into this PID namespace will fail with the error ENOMEM; it is
: not possible to create a new processes in a PID namespace whose "init"
: process has terminated.

and introducing a new error code would be too risky so let's stick to
ENOMEM for this case.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

signal: remove warning about using SI_TKILL in rt_[tg]sigqueueinfo

Sending SI_TKILL from rt_[tg]sigqueueinfo was deprecated, so now we issue
a warning on the first attempt of doing it.  We use WARN_ON_ONCE, which is
not informative and, what is worse, taints the kernel, making the trinity
syscall fuzzer complain false-positively from time to time.

It does not look like we need this warning at all, because the behaviour
changed quite a long time ago (2.6.39), and if an application relies on
the old API, it gets EPERM anyway and can issue a warning by itself.

So let us zap the warning in kernel.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ptrace: ptrace_detach() can no longer race with SIGKILL

ptrace_detach() re-checks ->ptrace under tasklist lock and calls
release_task() if __ptrace_detach() returns true.  This was needed because
the __TASK_TRACED tracee could be killed/untraced, and it could even pass
exit_notify() before we take tasklist_lock.

But this is no longer possible after 9899d11f6544 "ptrace: ensure
arch_ptrace/ptrace_request can never race with SIGKILL".  We can turn
these checks into WARN_ON() and remove release_task().

While at it, document the setting of child->exit_code.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Pavel Labath <labath@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ptrace: fix race between ptrace_resume() and wait_task_stopped()

ptrace_resume() is called when the tracee is still __TASK_TRACED.  We set
tracee->exit_code and then wake_up_state() changes tracee->state.  If the
tracer's sub-thread does wait() in between, task_stopped_code(ptrace => T)
wrongly looks like another report from tracee.

This confuses debugger, and since wait_task_stopped() clears ->exit_code
the tracee can miss a signal.

Test-case:

#include <stdio.h>
#include <unistd.h>
#include <sys/wait.h>
#include <sys/ptrace.h>
#include <pthread.h>
#include <assert.h>

int pid;

void *waiter(void *arg)
{
int stat;

for (;;) {
assert(pid == wait(&stat));
assert(WIFSTOPPED(stat));
if (WSTOPSIG(stat) == SIGHUP)
continue;

assert(WSTOPSIG(stat) == SIGCONT);
printf("ERR! extra/wrong report:%x\n", stat);
}
}

int main(void)
{
pthread_t thread;

pid = fork();
if (!pid) {
assert(ptrace(PTRACE_TRACEME, 0,0,0) == 0);
for (;;)
kill(getpid(), SIGHUP);
}

assert(pthread_create(&thread, NULL, waiter, NULL) == 0);

for (;;)
ptrace(PTRACE_CONT, pid, 0, SIGCONT);

return 0;
}

Note for stable: the bug is very old, but without 9899d11f6544 "ptrace:
ensure arch_ptrace/ptrace_request can never race with SIGKILL" the fix
should use lock_task_sighand(child).

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Pavel Labath <labath@google.com>
Tested-by: Pavel Labath <labath@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/fat: comment fix, fat_bits can be also 32

Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/fat: remove unnecessary includes

'fat.h' includes <linux/buffer_head.h> which includes <linux/fs.h> which
includes all the header files required for all *.c files fat filesystem.

[akpm@linux-foundation.org: fs/fat/iode.c needs seq_file.h]
[sfr@canb.auug.org.au: put one actually necessary include file back]
Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/fat: remove unnecessary defintion

'*sb' never used, so let's remote it and pass inode->i_sb directly to the
MSDOS_SB.

Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hfsplus: don't store special "osx" xattr prefix on-disk

On Mac OS X, HFS+ extended attributes are not namespaced.  Since we want
to be compatible with OS X filesystems and yet still support the Linux
namespacing system, the hfsplus driver implements a special "osx"
namespace that is reported for any attribute that is not namespaced
on-disk.  However, the current code for getting and setting these
unprefixed attributes is broken.

hfsplus_osx_setattr() and hfsplus_osx_getattr() are passed names that have
already had their "osx." prefixes stripped by the generic functions.  The
functions first, quite correctly, check those names to make sure that they
aren't prefixed with a known namespace, which would allow namespace access
restrictions to be bypassed.  However, the functions then prepend "osx."
to the name they're given before passing it on to hfsplus_getattr() and
hfsplus_setattr().  Not only does this cause the "osx." prefix to be
stored on-disk, defeating its purpose, it also breaks the check for the
special "com.apple.FinderInfo" attribute, which is reported for all files,
and as a consequence makes some userspace applications (e.g.  GNU patch)
fail even when extended attributes are not otherwise in use.

There are five commits which have touched this particular code:

  127e5f5ae51e ("hfsplus: rework functionality of getting, setting and deleting of extended attributes")
  b168fff72109 ("hfsplus: use xattr handlers for removexattr")
  bf29e886b242 ("hfsplus: correct usage of HFSPLUS_ATTR_MAX_STRLEN for non-English attributes")
  fcacbd95e121 ("fs/hfsplus: move xattr_name allocation in hfsplus_getxattr()")
  ec1bbd346f18 ("fs/hfsplus: move xattr_name allocation in hfsplus_setxattr()")

The first commit creates the functions to begin with.  The namespace is
prepended by the original code, which I believe was correct at the time,
since hfsplus_?etattr() stripped the prefix if found.  The second commit
removes this behavior from hfsplus_?etattr() and appears to have been
intended to also remove the prefixing from hfsplus_osx_?etattr().
However, what it actually does is remove a necessary strncpy() call
completely, breaking the osx namespace entirely.  The third commit re-adds
the strncpy() call as it was originally, but doesn't mention it in its
commit message.  The final two commits refactor the code and don't affect
its functionality.

This commit does what b168fff attempted to do (prevent the prefix from
being added), but does it properly, instead of passing in an empty buffer
(which is what b168fff actually did).

Fixes: b168fff72109 ("hfsplus: use xattr handlers for removexattr")
Signed-off-by: Thomas Hebb <tommyhebb@gmail.com>
Cc: Hin-Tak Leung <htl10@users.sourceforge.net>
Cc: Sergei Antonov <saproj@gmail.com>
Cc: Anton Altaparmakov <anton@tuxera.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Christian Kujau <lists@nerdbynature.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hfsplus: fix expand when not enough available space

Fix a bug which is reproduced as follows. Create a file:

 echo abc > test_file

Try to expand the file beyond available space:

 truncate --size=<size exceeding available space> test_file

Since HFS+ does not support file size > allocated size, truncate should
fail.  However, it ends successfully.  The driver returns success despite
having been unable to allocate the requested space for the file.  Also
filesystem check finds an error:

 Checking catalog file.
 Incorrect size for file test_file
 (It should be 469094400 instead of 1000000000)

Add a piece of code analogous to code in the fat driver.  Now a proper
error is returned and filesystem remains consistent.

Signed-off-by: Sergei Antonov <saproj@gmail.com>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Hin-Tak Leung <htl10@users.sourceforge.net>
Reviewed-by: Anton Altaparmakov <anton@tuxera.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Sougata Santra <sougata@tuxera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hfsplus: incorrect return value

In case of memory allocation error, the return should be -ENOMEM, instead
of -ENOSPC.

Signed-off-by: Chengyu Song <csong84@gatech.edu>
Reviewed-by: Sergei Antonov <saproj@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/hfsplus: replace if/BUG by BUG_ON

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/hfsplus: use bool instead of int for is_known_namespace() return value

is_known_namespace() only returns true/false.  Also remove inline and let
compiler decide what to do with static functions.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/hfsplus: atomically set inode->i_flags

According to commit 5f16f3225b06 ("ext4: atomically set inode->i_flags in
ext4_set_inode_flags()").

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/hfsplus: move xattr_name allocation in hfsplus_setxattr()

security/trusted/user/osx setxattr did the same
xattr_name initialization. Move that operation in hfsplus_setxattr().

Tested with security/trusted/user getfattr/setfattr

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/hfsplus: move xattr_name allocation in hfsplus_getxattr()

security/trusted/user/osx getxattr did the same
xattr_name initialization. Move that operation in hfsplus_getxattr().

Tested with security/trusted/user getfattr/setfattr

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hfsplus: add missing curly braces in hfsplus_delete_cat()

This doesn't change how the code works, but clearly the curly braces were
intended.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Sougata Santra <sougata@tuxera.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hfs: incorrect return values

In case of memory allocation error, the return should be -ENOMEM, instead
of -ENOSPC.

Signed-off-by: Chengyu Song <csong84@gatech.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

nilfs2: use inode_set_flags() in nilfs_set_inode_flags()

Use inode_set_flags() to atomically set i_flags instead of clearing out
the S_IMMUTABLE, S_APPEND, etc.  flags and then setting them from the
FS_IMMUTABLE_FL, FS_APPEND_FL flags to avoid a race where an immutable
file has the immutable flag cleared for a brief window of time.

This is a similar fix to commit 5f16f3225b06 ("ext4: atomically set
inode->i_flags in ext4_set_inode_flags()").

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

nilfs2: put out gfp mask manipulation from nilfs_set_inode_flags()

nilfs_set_inode_flags() function adjusts gfp-mask of inode->i_mapping as
well as i_flags, however, this coupling of operations is not appropriate.

For instance, nilfs_ioctl_setflags(), one of three callers of
nilfs_set_inode_flags(), doesn't need to reinitialize the gfp-mask at all.
 In addition, nilfs_new_inode(), another caller of
nilfs_set_inode_flags(), doesn't either because it has already initialized
the gfp-mask.

Only __nilfs_read_inode(), the remaining caller, needs it.  So, this moves
the gfp mask manipulation to __nilfs_read_inode() from
nilfs_set_inode_flags().

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

nilfs2: fix gcc warning at nilfs_checkpoint_is_mounted()

Fix the following build warning:

 fs/nilfs2/super.c: In function 'nilfs_checkpoint_is_mounted':
 fs/nilfs2/super.c:1023:10: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
   if (cno < 0 || cno > nilfs->ns_cno)
           ^

This warning indicates that the comparision "cno < 0" is useless because
variable "cno" has an unsigned integer type "__u64".

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

nilfs2: improve execution time of NILFS_IOCTL_GET_CPINFO ioctl

The older a filesystem gets, the slower lscp command becomes.  This is
because nilfs_cpfile_do_get_cpinfo() function meets more hole blocks
as the start offset of valid checkpoint numbers gets bigger.

This reduces the overhead by skipping hole blocks efficiently with
nilfs_mdt_find_block() helper.

A measurement result of this patch is as follows:

Before:
$ time lscp
                 CNO        DATE     TIME  MODE  FLG      BLKCNT       ICNT
             5769303  2015-02-22 19:31:33   cp    -          108          1
             5769304  2015-02-22 19:38:54   cp    -          108          1

real    0m0.182s
user    0m0.003s
sys     0m0.180s

After:
$ time lscp
                 CNO        DATE     TIME  MODE  FLG      BLKCNT       ICNT
             5769303  2015-02-22 19:31:33   cp    -          108          1
             5769304  2015-02-22 19:38:54   cp    -          108          1

real    0m0.003s
user    0m0.001s
sys     0m0.002s

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

nilfs2: add helper to find existent block on metadata file

Add a new metadata file function, nilfs_mdt_find_block(), which finds
an existent block on a metadata file in a given range of blocks.  This
function skips continuous hole blocks efficiently by using
nilfs_bmap_seek_key().

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

nilfs2: add bmap function to seek a valid key

Add a new bmap function, nilfs_bmap_seek_key(), which seeks a valid
entry and returns its key starting from a given key.  This function
can be used to skip hole blocks efficiently.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

nilfs2: unify type of key arguments in bmap interface

The type of key arguments in block mapping interface varies depending
on function.  For instance, nilfs_bmap_lookup_at_level() takes "__u64"
for its key argument whereas nilfs_bmap_lookup() takes "unsigned
long".

This fits them to "__u64" to eliminate the variation.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

nilfs2: use bgl_lock_ptr()

Simplify nilfs_mdt_bgl_lock() by utilizing bgl_lock_ptr() helper in
<linux/blockgroup_lock.h>.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

nilfs2: use set_mask_bits() for operations on buffer state bitmap

nilfs_forget_buffer(), nilfs_clear_dirty_page(), and
nilfs_segctor_complete_write() are using a bunch of atomic bit operations
against buffer state bitmap.

This reduces the number of them by utilizing set_mask_bits() macro.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

nilfs2: do not use async write flag for segment summary buffers

The async write flag is introduced to nilfs2 in the commit 7f42ec394156
("nilfs2: fix issue with race condition of competition between segments
for dirty blocks"), but the flag only makes sense for data buffers and
btree node buffers.  It is not needed for segment summary buffers.

This gets rid of the latter uses as part of refactoring of atomic bit
operations on buffer state bitmap.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

befs: replace typedef befs_inode_info by structure

See Documentation/CodingStyle

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

befs: replace typedef befs_sb_info by structure

See Documenation/CodingStyle

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

befs: replace typedef befs_mount_options by structure

See Documentation/CodingStyle

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc: use more standard kernel logging styles

Neaten the logging a bit by adding #define pr_fmt

Miscellanea:

o Remove __FILE__/__func__ uses
o Coalesce formats adding missing spaces
o Align arguments
o (rtc-cmos) Integrated 2 consecutive messages

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: Chanwoo Choi <cw00.choi@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-hym8563.c: fix swapped enable/disable of clockout control bit

The hym8563 datasheet describes the clock output control-bit as "when set
to logic 0, the square wave output is enable, when set to logic 1, the
CLKOUT output is inhibited".  But in reality the setting is exactly
opposite.

Before now, the clock output was not really used, but on the rk3288 soc
this generated clock is used to supply the temperature sensor block and
the swapped bit value prevented it from working.  With the corrected
value, the tsadc now reports correct values.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-s3c.c: remove one superfluous rtc_valid_tm() check

s3c_rtc_gettime() already returns the result of rtc_valid_tm() on the
obtained time so get rid of another call to rtc_valid_tm().

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-omap.c: use module_platform_driver

module_platform_driver_probe() prevents driver from requesting probe
deferral.  So using module_platform_drive() to support probe deferral.

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Tero Kristo <t-kristo@ti.com>
Cc: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/Kconfig: update Kconfig for OMAP RTC

RTC is present in AM43xx and DRA7xx also.  Updating the Kconfig to depend
on ARCH_OMAP or ARCH_DAVINCI

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Tero Kristo <t-kristo@ti.com>
Cc: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-omap.c: unlock and lock rtc registers before and after register writes

RTC module contains a kicker mechanism to prevent any spurious writes from
changing the register values.  This mechanism requires two MMR writes to
the KICK0 and KICK1 registers with exact data values before the kicker
lock mechanism is released.

Currently the driver release the lock in the probe and leaves it enabled
until the rtc driver removal.  This eliminates the idea of preventing
spurious writes when RTC driver is loaded.  So implement rtc lock and
unlock functions before and after register writes.

This is as advised by Paul to implement lock and unlock functions in the
driver and not to unlock and leave it in probe.  The same discussion can
be seen here:
http://www.mail-archive.com/linux-omap%40vger.kernel.org/msg111588.html

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Tero Kristo <t-kristo@ti.com>
Cc: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-s3c.c: fix failed first read of RTC time

Initialize the device time (if it is wrong) before registering RTC device
to fix following error message during rtc-s3c probe:

[    2.215414] rtc (null): read_time: fail to read
[    2.216322] s3c-rtc 10070000.rtc: rtc core: registered s3c as rtc1

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc: hctosys: use function name in the error log

Use function name in the error log instead of __FILE__.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/interface.c: __rtc_read_time: reduce log level

__rtc_read_time logs should be debug logs instead of error logs.

For example, when the RTC clock is not set, it's not really useful
to print a kernel error log every time someone tries to read the clock:

~ # hwclock -r
[  604.508263] rtc rtc0: read_time: fail to read
hwclock: RTC_RD_TIME: Invalid argument

If there's a real error, it's likely that lower level or higher level
code will tell it anyway. Make these logs debug logs, and also print
the error code for the read failure.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/class.c: initialize rtc name early

In some error cases RTC name is used before it is initialized:

rtc-rs5c372 0-0032: clock needs to be set
rtc-rs5c372 0-0032: rs5c372b found, 24hr, driver version 0.6
rtc (null): read_time: fail to read
rtc-rs5c372 0-0032: rtc core: registered rtc-rs5c372 as rtc0

Fix by initializing the name early.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-s5m.c: add support for S2MPS13 RTC

The S2MPS13 RTC is almost the same as S2MPS14. The differences when
updating alarm are:
1. Set WUDR+AUDR field instead of WUDR+RUDR.
2. Clear the AUDR field later (it is not auto-cleared).

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: Add Alexandre Belloni as an RTC maintainer

I've noticed that most of the patches for the RTC subsystem are currently
either taken directly by Andrew or going through another maintainer's
tree, quite often without an Acked-by or Reviewed-by tag.

I'd like to propose myself as the RTC subsystem co-maintainer, to mainly
help Alessandro reviewing incoming patches and maintain a subsystem tree
to avoid having the RTC patches going through trees when they have no
particular dependencies.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc: driver for Conexant Digicolor CX92755 on-chip RTC

Add driver for the RTC hardware block on the Conexant CX92755 SoC, from
the Digicolor series of SoCs.  Tested on the Equinox evaluation board for
the CX92755 chip.

[akpm@linux-foundation.org: build command arrays at compile-time]
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc: digicolor: document device tree binding

Add a device tree binding documentation to the Real Time Clock hardware
block on the Conexant CX92755 SoC.  The CX92755 is from the Digicolor SoCs
series.  Other SoCs in that series may share the same hardware block.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-hym8563.c: return clock rate even when clock is disabled

When the clock is disabled, do not return a rate of 0 but instead return
the rate the clock will be running at after it gets enabled.  This
prevents problems when the core clock code is trying to determine a
suitable rate, while the clock is still off.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-da9052.c: register ability of alarm to wake device from suspend

Signed-off-by: Adam Ward <adam.ward.opensource@diasemi.com>
Tested-by: Adam Ward <adam.ward.opensource@diasemi.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-da9052.c: add constraints to set valid year

Signed-off-by: Adam Ward <adam.ward.opensource@diasemi.com>
Tested-by: Adam Ward <adam.ward.opensource@diasemi.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-da9052.c: add extra reads with timeouts to avoid returning partially updated values

The RTC is in a different clock domain so a quick read after write
can retrieve a mangled value of the old/new values

Signed-off-by: Adam Ward <adam.ward.opensource@diasemi.com>
Tested-by: Adam Ward <adam.ward.opensource@diasemi.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-ds1685.c: fix sparse warnings

Fix two minor sparse warnings:

  CHECK   drivers/rtc/rtc-ds1685.c
  drivers/rtc/rtc-ds1685.c:2178:1: warning: function 'ds1685_rtc_poweroff' with external linkage has definition
  drivers/rtc/rtc-ds1685.c:802:23: warning: Using plain integer as NULL pointer

Fixes: aaaf5fbf56f1 ("rtc: add driver for DS1685 family of real time clocks")
Signed-off-by: Joshua Kinard <kumba@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-ds1685.c: remove .owner assignment from platform_driver

The rtc driver core now sets the platform_driver 'owner' property, so
remove the assignment from the DS1685 driver.

Fixes: aaaf5fbf56f1: "rtc: add driver for DS1685 family of real time clocks"
Signed-off-by: Joshua Kinard <kumba@gentoo.org>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-ab-b5ze-s3.c: constify struct regmap_config

The regmap_config struct may be const because it is not modified by the
driver and regmap_init() accepts pointer to const.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-s3c.c: delete duplicate clock control

The current functions in s3c-rtc driver execute clk_enable/disable() to
control clocks and some functions execute s3c_rtc_alarm_clk_enable()
unnecessarily.  So this patch deletes the duplicate clock control and
spilts s3c_rtc_alarm_clk_enable() out as
s3c_rtc_enable_clk()/s3c_rtc_disable_clk() to improve readability.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc: hctosys: do not treat lack of RTC device as error

When using device trees on the ARM platform, it is not certain at compile
time whether or not the system will have a RTC.

If one enables CONFIG_HCTOSYS just in case the system booted has a RTC,
and it turns out not to be, this will result in a big fat "unable to open
rtc device" error being printed to console, even when "quiet" is set in
the kernel cmdline.

Fix this by outputting the message with loglevel info instead.

Signed-off-by: Floris Bos <bos@je-eigen-domein.nl>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-x1205.c: use sign_extend32() for sign extension

Despite its name, sign_extend32() is safe to use for 8 bit types too.
(See https://lkml.org/lkml/2015/1/18/289).

Signed-off-by: Martin Kepplinger <martink@posteo.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-em3027.c: add device tree support

Set the of_match_table for this driver so that devices can be described in
the device tree.  This device is used in the Trimslice and is already
defined in the Trimslice device tree.

Signed-off-by: Peter Robinson <pbrobinson@gmail.com>
Cc: Mike Rapoport <mike@compulab.co.il>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Grant Likely <grant.likely@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc: stmp3xxx: use optional crystal in low power states

The rtc's status register allows to determine if a 32k crystal is
connected to keep the rtc running in low power states provided the
corresponding fuse bits were blown correctly during production.  (In case
they were not, the right frequency can be stated in the device tree.) If
there is no such crystal available force the 24 MHz XTAL clock to keep
running to retain the right date and time.  Otherwise use the crystal to
save some power.

It would be nice to only switch to the crystal when the XTAL clock is
about to be disabled and keep the crystal off when unneeded because XTAL
is always on while the chip is powered on.  But as sudden power loss isn't
detectable this is not save.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-pcf8563.c: simplify return from function

This commit does not change any logic here.  It just makes the code easier
to read.

This is how it looked like:
If err != 0 return err;
else return 0;

Signed-off-by: Robert Kmiec <robert.r.kmiec@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kasan: Makefile: shut up warnings if CONFIG_COMPILE_TEST=y

It might be annoying to constantly see this:

scripts/Makefile.kasan:16: Cannot use CONFIG_KASAN: -fsanitize=kernel-address is not supported by compiler

while performing allmodconfig/allyesconfig build tests.
Disable this warning if CONFIG_COMPILE_TEST=y.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/binfmt_misc.c: simplify entry_status()

sprintf() reliably returns the number of characters printed, so we don't
need to ask strlen() where we are.  Also replace calling sprintf("%02x")
in a loop with the much simpler bin2hex().

[akpm@linux-foundation.org: it's odd to include kernel.h after everything else]
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: avoid "spaces required around that ':'" false positive

Since commit 1f65f947a6a8 ("checkpatch: add checks for question mark and
colon spacing") back in 2008, checkpatch has reported false positive for
asm volatile uses of "::" checkpatch thinks colons should always have
spaces around it.

Add an exception for colons with colons on either side for this valid asm
volatile (and c++) use.

Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Yehuda Yitschak <yehuday@marvell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: fix --fix use with a patch of multiple files

If a patch touches multiple files, the --fix and --fix-inplace option
doesn't keep the proper line count and makes the new patch file not able
to be applied via bad offset line numbers when lines are added or deleted
by the --fix option.

Dunno how that extra backslash snuck in there.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

errno.h: Improve ENOSYS's comment

ENOSYS is the mechanism used by user code to detect whether the running
kernel implements a given system call.  It should not be returned by
anything except an unimplemented system call.

Unfortunately, it is rather frequently used in the kernel to indicate that
various new functions of existing system calls are not implemented.  This
should be discouraged.

Improve the comment in errno.h to help clarify ENOSYS's purpose.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch.pl: new instances of ENOSYS are errors

ENOSYS means that a nonexistent system call was called.  We have a
bad habit of using it for things like invalid operations on
otherwise valid syscalls.  We should avoid this in new code.

Pervasive incorrect usage of ENOSYS came up at the kernel summit ABI
review discussion.  Let's see if checkpatch can help.

I'll submit a separate patch for include/uapi/asm-generic/errno.h.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: add a test for const with __read_mostly uses

const objects shouldn't be __read_mostly.  They are read-only.

Marking these objects as __read_mostly causes section conflicts with LTO
linking.

So add a test to try to avoid this issue.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: improve operator spacing check

Code such as:
       x = timercmp(&now, &end, <);
Will currently trigger a checkpatch error. e.g.

ERROR: spaces required around that '<'

This is because the "Ignore operators passed as parameters" check looks
only for a comma following the operator.  Improve the check by also
looking for a close parenthesis.

Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: add 'Prefer ARRAY_SIZE" test

Add a test for sizeof(foo)/sizeof(foo[0]) that could be ARRAY_SIZE(foo).

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: add uart_ops to normally const structs

Add another struct to the list of normally const struct types

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: add #define foo "string" long line exception

There are #defines with long string constants like:
#define foo "some really long string > 80 columns"
Add a long line exception for them.

Miscellanea:

Use the $String variable for slightly better readability

Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Madalin-Cristian Bucur <madalin.bucur@freescale.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch, SubmittingPatches: suggest line wrapping commit messages at 75 columns

Commit messages lines are sometimes overly long.

Suggest line wrapping at 75 columns so the default git commit log
indentation of 4 plus the commit message text still fits on an 80 column
screen.

Add a checkpatch test for long commit messages lines too.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: David Miller <davem@davemloft.net>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: don't ask for asm/file.h to linux/file.h unconditionally

Currently checkpatch warns when asm/file.h is included and linux/file.h
exists.  That conversion can be made when linux/file.h includes asm/file.h
which is not always the case.(See signal.h)

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Andy Whitcroft <apw@canonical.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: add test for repeated const uses

Using 'const <type> const *' is generally meant to be written 'const
<type> * const'.

Add a test for the miswritten form.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: improve return negative errno check

Add a few conditions to the test to find
return (ERRNO);

Make the output message a bit less cryptic too.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: match more world writable permissions

Currently checkpatch will fuss if one uses world writable settings in
debugfs files and DEVICE_ATTR uses by testing S_IWUGO but not testing
S_IWOTH, S_IRWXUGO or S_IALLUGO.

Extend the check to catch all cases exporting world writable permissions
including octal values.

[akpm@linux-foundation.org: remove stray $]
Signed-off-by: Joe Perches <joe@perches.com>
Original-patch-by: Nicholas Mc Guire <hofrat@osadl.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: add optional --codespell dictionary to find more typos

If a codespell dictionary exists, use it if desired.  default is off,
maybe it could be turned on later.

codespell's dictionary format allows multiple possible corrections, ignore
that for now and only use the first suggestion.

Also add \b to spelling test so that consecutive misspelled words
are found properly.

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masanari Iida <standby24x7@gmail.com>
Cc: Lucas De Marchi <lucas.de.marchi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: spell check reudce

References: http://mid.gmane.org/1424977312-24902-1-git-send-email-ville.syrjala@linux.intel.com

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: add spell checking of email subject line

Only commit log and patch additions are checked for typos and spelling
errors currently.  Add a check of the email subject line too.

Signed-off-by: Joe Perches <joe@perches.com>
Suggested-by: Jani Nikula <jani.nikula@linux.intel.com>
Tested-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

checkpatch: improve "no space is necessary after a cast" test

The "no space is necessary after a cast" sizeof exclusion doesn't work
properly.

The test reports a false positive for code like:

BUILD_BUG_ON(sizeof(struct batadv_bla_claim_dst) != 6);

Make it work, simplify the exclusions, and add some comments.

Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

firmware/ihex2fw.c: restore missing default in switch statement

Commit 2473238eac95 ("ihex: add support for CS:IP/EIP records") removes
the "default:" statement in the switch block, making the "return
usage();" line dead code and ihex2fw silently ignoring unknown options.
Restore this statement.

This bug was found by building with HOSTCC=clang and adding
-Wunreachable-code-return to HOSTCFLAGS.

Fixes: 2473238eac95 ("ihex: add support for CS:IP/EIP records")
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/bitmap.c: bitmap_[empty,full]: remove code duplication

bitmap_empty() has its own implementation.  But it's clearly as simple as:

find_first_bit(src, nbits) == nbits

The same is true for 'bitmap_full'.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Cc: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ASoC: pcm512x: use DIV_ROUND_CLOSEST_ULL() from kernel.h

Now that the kernel provides DIV_ROUND_CLOSEST_ULL(), drop the internal
implementation and use the kernel one.

Signed-off-by: Javi Merino <javi.merino@arm.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Cc: Peter Rosin <peda@axentia.se>
Acked-by: Mark Brown <broonie@kernel.org>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

media: cxd2820r: use DIV_ROUND_CLOSEST_ULL()

Now that the kernel provides DIV_ROUND_CLOSEST_ULL(), drop the internal
implementation and use the kernel one.

Signed-off-by: Javi Merino <javi.merino@arm.com>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Acked-by: Antti Palosaari <crope@iki.fi>
Reviewed-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

cpuidle: menu: use DIV_ROUND_CLOSEST_ULL()

Now that the kernel provides DIV_ROUND_CLOSEST_ULL(), drop the internal
implementation and use the kernel one.

Signed-off-by: Javi Merino <javi.merino@arm.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

clk: bcm/kona: use DIV_ROUND_CLOSEST_ULL()

Now that the kernel provides DIV_ROUND_CLOSEST_ULL(), drop the internal
implementation and use the kernel one.

Signed-off-by: Javi Merino <javi.merino@arm.com>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Alex Elder <elder@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel.h: implement DIV_ROUND_CLOSEST_ULL

We have grown a number of different implementations of
DIV_ROUND_CLOSEST_ULL throughout the kernel.  Move the i915 one to
kernel.h so that it can be reused.

Signed-off-by: Javi Merino <javi.merino@arm.com>
Reviewed-by: Jeff Epler <jepler@unpythonic.net>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Guenter Roeck <linux@roeck-us.net>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Alex Elder <elder@linaro.org>
Cc: Antti Palosaari <crope@iki.fi>
Cc: Javi Merino <javi.merino@arm.com>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/vsprintf.c: improve put_dec_trunc8 slightly

I hadn't had enough coffee when I wrote this. Currently, the final
increment of buf depends on the value loaded from the table, and
causes gcc to emit a cmov immediately before the return. It is smarter
to let it depend on r, since the increment can then be computed in
parallel with the final load/store pair. It also shaves 16 bytes of
.text.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hwmon: (w83795) use find_closest_descending() in pwm_freq_to_reg()

Replace the loop iterating over pwm_freq_cksel0 with a call to
find_closest_descending().

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hwmon: (lm85) use find_closest() in x_TO_REG() functions

Replace RANGE_TO_REG() and FREQ_TO_REG() implementations with
calls to find_closest().

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hwmon: (ina2xx) replace ina226_avg_bits() with find_closest()

Use find_closest() to locate the closest average in ina226_avg_tab.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

documentation: update CodingStyle on local variables naming in macros

Describe proper naming convention for local variables in macros
resembling functions.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

util_macros.h: add find_closest() macro

This series unduplicates the code used to find the member in an array
closest to 'x'.

The first patch adds a macro implementing the algorithm in two flavors -
for arrays sorted in ascending and descending order.  The second updates
Documentation/CodingStyle on the naming convention for local variables in
macros resembling functions.  Other three patches replace duplicated code
with calls to one of these macros in some hwmon drivers.

This patch (of 5):

Searching for the member of an array closest to 'x' is duplicated in
several places.

Add a new include - util_macros.h - and two macros that implement this
algorithm for arrays sorted both in ascending and descending order.

Uses linear search.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/dma-debug: fix bucket_find_contain()

bucket_find_contain() will search the bucket list for a dma_debug_entry.
When the entry isn't found it needs to search other buckets too, since
only the start address of a dma range is hashed (which might be in a
different bucket).

A copy of the dma_debug_entry is used to get the previous hash bucket
but when its list is searched the original dma_debug_entry is to be used
not its modified copy.

This fixes false "device driver tries to sync DMA memory it has not allocated"
warnings.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Horia Geanta <horia.geanta@freescale.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/vsprintf.c: even faster binary to decimal conversion

The most expensive part of decimal conversion is the divisions by 10
(albeit done using reciprocal multiplication with appropriately chosen
constants).  I decided to see if one could eliminate around half of
these multiplications by emitting two digits at a time, at the cost of a
200 byte lookup table, and it does indeed seem like there is something
to be gained, especially on 64 bits.  Microbenchmarking shows
improvements ranging from -50% (for numbers uniformly distributed in [0,
2^64-1]) to -25% (for numbers heavily biased toward the smaller end, a
more realistic distribution).

On a larger scale, perf shows that top, one of the big consumers of /proc
data, uses 0.5-1.0% fewer cpu cycles.

I had to jump through some hoops to get the 32 bit code to compile and run
on my 64 bit machine, so I'm not sure how relevant these numbers are, but
just for comparison the microbenchmark showed improvements between -30%
and -10%.

The bloat-o-meter costs are around 150 bytes (the generated code is a
little smaller, so it's not the full 200 bytes) on both 32 and 64 bit.
I'm aware that extra cache misses won't show up in a microbenchmark as
used above, but on the other hand decimal conversions often happen in bulk
(for example in the case of top).

I have of course tested that the new code generates the same output as the
old, for both the first and last 1e10 numbers in [0,2^64-1] and 4e9
'random' numbers in-between.

Test and verification code on github: https://github.com/Villemoes/dec.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Tested-by: Jeff Epler <jepler@unpythonic.net>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib: rename lib/find_next_bit.c to lib/find_bit.c

This file contains implementation for all find_*_bit{,_le}
So giving it more generic name looks reasonable.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib: move find_last_bit to lib/find_next_bit.c

Currently all 'find_*_bit' family is located in lib/find_next_bit.c,
except 'find_last_bit', which is in lib/find_last_bit.c. It seems,
there's no major benefit to have it separated.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib: find_*_bit reimplementation

This patchset does rework to find_bit function family to achieve better
performance, and decrease size of text.  All rework is done in patch 1.
Patches 2 and 3 are about code moving and renaming.

It was boot-tested on x86_64 and MIPS (big-endian) machines.
Performance tests were ran on userspace with code like this:

/* addr[] is filled from /dev/urandom */
start = clock();
while (ret < nbits)
ret = find_next_bit(addr, nbits, ret + 1);

end = clock();
printf("%ld\t", (unsigned long) end - start);

On Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz measurements are: (for
find_next_bit, nbits is 8M, for find_first_bit - 80K)

find_next_bit: find_first_bit:
new current new current
26932 43151 14777 14925
26947 43182 14521 15423
26507 43824 15053 14705
27329 43759 14473 14777
26895 43367 14847 15023
26990 43693 15103 15163
26775 43299 15067 15232
27282 42752 14544 15121
27504 43088 14644 14858
26761 43856 14699 15193
26692 43075 14781 14681
27137 42969 14451 15061
... ...

find_next_bit performance gain is 35-40%;
find_first_bit - no measurable difference.

On ARM machine, there is arch-specific implementation for find_bit.

Thanks a lot to George Spelvin and Rasmus Villemoes for hints and
helpful discussions.

This patch (of 3):

New implementations takes less space in source file (see diffstat) and in
object.  For me it's 710 vs 453 bytes of text.  It also shows better
performance.

find_last_bit description fixed due to obvious typo.

[akpm@linux-foundation.org: include linux/bitmap.h, per Rasmus]
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: George Spelvin <linux@horizon.com>
Cc: Alexey Klimov <klimov.linux@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Daniel Borkmann <dborkman@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Valentin Rothberg <valentinrothberg@gmail.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

alpha: forward declare struct pt_regs in processor.h

Removal of exec domains uncovered this new warning.  processor.h re-used
struct pt_regs from personality.h which is now gone.

  ./arch/alpha/include/asm/processor.h:47:33: warning: 'struct pt_regs' declared inside parameter list [enabled by default]

Signed-off-by: Richard Weinberger <richard@nod.at>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

crypto: fix broken crypto_register_instance() module handling

Commit 9c521a200bc3 ("crypto: api - remove instance when test failed")
tried to grab a module reference count before the module was even set.

Worse, it then goes on to free the module reference count after it is
set so you quickly end up with a negative module reference count which
prevents people from using any instances belonging to that module.

This patch moves the module initialisation before the reference
count.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge branch 'akpm' (patches from Andrew)

Merge second patchbomb from Andrew Morton:

 - the rest of MM

 - various misc bits

 - add ability to run /sbin/reboot at reboot time

 - printk/vsprintf changes

 - fiddle with seq_printf() return value

* akpm: (114 commits)
  parisc: remove use of seq_printf return value
  lru_cache: remove use of seq_printf return value
  tracing: remove use of seq_printf return value
  cgroup: remove use of seq_printf return value
  proc: remove use of seq_printf return value
  s390: remove use of seq_printf return value
  cris fasttimer: remove use of seq_printf return value
  cris: remove use of seq_printf return value
  openrisc: remove use of seq_printf return value
  ARM: plat-pxa: remove use of seq_printf return value
  nios2: cpuinfo: remove use of seq_printf return value
  microblaze: mb: remove use of seq_printf return value
  ipc: remove use of seq_printf return value
  rtc: remove use of seq_printf return value
  power: wakeup: remove use of seq_printf return value
  x86: mtrr: if: remove use of seq_printf return value
  linux/bitmap.h: improve BITMAP_{LAST,FIRST}_WORD_MASK
  MAINTAINERS: CREDITS: remove Stefano Brivio from B43
  .mailmap: add Ricardo Ribalda
  CREDITS: add Ricardo Ribalda Delgado
  ...

parisc: remove use of seq_printf return value

The seq_printf return value, because it's frequently misused,
will eventually be converted to void.

See: commit 1f33c41c03da ("seq_file: Rename seq_overflow() to
     seq_has_overflowed() and make public")

Signed-off-by: Joe Perches <joe@perches.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lru_cache: remove use of seq_printf return value

The seq_printf return value, because it's frequently misused,
will eventually be converted to void.

See: commit 1f33c41c03da ("seq_file: Rename seq_overflow() to
     seq_has_overflowed() and make public")

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>