litmus-rt-ext-res.git/drivers/misc/ibmasm, branch EXT-RES

fs: Replace CURRENT_TIME with current_time() for inode timestamps

2016-09-28T01:06:21+00:00

CURRENT_TIME macro is not appropriate for filesystems as it
doesn't use the right granularity for filesystem timestamps.
Use current_time() instead.

CURRENT_TIME is also not y2038 safe.

This is also in preparation for the patch that transitions
vfs timestamps to use 64 bit time and hence make them
y2038 safe. As part of the effort current_time() will be
extended to do range checks. Hence, it is necessary for all
file system timestamps to use current_time(). Also,
current_time() will be transitioned along with vfs to be
y2038 safe.

Note that whenever a single call to current_time() is used
to change timestamps in different inodes, it is because they
share the same time granularity.

Signed-off-by: Deepa Dinamani 
Reviewed-by: Arnd Bergmann 
Acked-by: Felipe Balbi 
Acked-by: Steven Whitehouse 
Acked-by: Ryusuke Konishi 
Acked-by: David Sterba 
Signed-off-by: Al Viro

mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

2016-04-04T17:41:08+00:00

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 -  << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> ;

 -  >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> ;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov 
Acked-by: Michal Hocko 
Signed-off-by: Linus Torvalds

misc: ibmasm: Replace timeval with timespec64

2016-02-12T04:06:46+00:00

This patch replaces timeval with timespec64 as 32 bit 'struct timeval'
will not give current time beyond year 2038.

The patch changes the code to use ktime_get_real_ts64() which returns
a 'struct timespec64' instead of do_gettimeofday() which returns a
'struct timeval'

This patch also alters the format strings in sprintf() for now.tv_sec
and now.tv_nsec to incorporate 'long long' on 32 bit architectures and
leading zeroes respectively.

Signed-off-by: Amitoj Kaur Chawla 
Reviewed-by: Arnd Bergmann 
Signed-off-by: Greg Kroah-Hartman

kbuild: Allow to specify composite modules with modname-m

2015-11-25T10:23:25+00:00

This allows to write

  drm-$(CONFIG_AGP) += drm_agpsupport.o

without having to handle CONFIG_AGP=y vs. CONFIG_AGP=m. Only support
this syntax for modules, since built-in code depending on something
modular cannot work and init/Makefile actually relies on the current
semantics. There are a few drivers which adapted to the current
semantics out of necessity; these are fixed to also work when the
respective subsystem is modular.

Acked-by: Peter Chen  [chipidea]
Signed-off-by: Michal Marek

misc: ibmasm: remove unnecessary pci_set_drvdata()

2013-09-26T16:13:54+00:00

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.

Signed-off-by: Jingoo Han 
Signed-off-by: Greg Kroah-Hartman

misc: ibmasm: Remove casting the return value which is a void pointer

2013-09-26T15:53:23+00:00

Casting the return value which is a void pointer is redundant.
The conversion from void pointer to any other pointer type is
guaranteed by the C programming language.

Signed-off-by: Jingoo Han 
Signed-off-by: Greg Kroah-Hartman

ibmasmfs: don't bother passing superblock when not needed

2013-09-04T02:52:50+00:00

Signed-off-by: Al Viro

fs: Limit sys_mount to only request filesystem modules.

2013-03-04T03:36:31+00:00

Modify the request_module to prefix the file system type with "fs-"
and add aliases to all of the filesystems that can be built as modules
to match.

A common practice is to build all of the kernel code and leave code
that is not commonly needed as modules, with the result that many
users are exposed to any bug anywhere in the kernel.

Looking for filesystems with a fs- prefix limits the pool of possible
modules that can be loaded by mount to just filesystems trivially
making things safer with no real cost.

Using aliases means user space can control the policy of which
filesystem modules are auto-loaded by editing /etc/modprobe.d/*.conf
with blacklist and alias directives.  Allowing simple, safe,
well understood work-arounds to known problematic software.

This also addresses a rare but unfortunate problem where the filesystem
name is not the same as it's module name and module auto-loading
would not work.  While writing this patch I saw a handful of such
cases.  The most significant being autofs that lives in the module
autofs4.

This is relevant to user namespaces because we can reach the request
module in get_fs_type() without having any special permissions, and
people get uncomfortable when a user specified string (in this case
the filesystem type) goes all of the way to request_module.

After having looked at this issue I don't think there is any
particular reason to perform any filtering or permission checks beyond
making it clear in the module request that we want a filesystem
module.  The common pattern in the kernel is to call request_module()
without regards to the users permissions.  In general all a filesystem
module does once loaded is call register_filesystem() and go to sleep.
Which means there is not much attack surface exposed by loading a
filesytem module unless the filesystem is mounted.  In a user
namespace filesystems are not mounted unless .fs_flags = FS_USERNS_MOUNT,
which most filesystems do not set today.

Acked-by: Serge Hallyn 
Acked-by: Kees Cook 
Reported-by: Kees Cook 
Signed-off-by: "Eric W. Biederman"

misc: remove use of __devexit

2012-11-21T20:53:32+00:00

CONFIG_HOTPLUG is going away as an option so __devexit is no
longer needed.

Signed-off-by: Bill Pemberton 
Cc: "Michał Mirosław" 
Cc: Wolfram Sang 
Cc: Eric Piel 
Cc: Jiri Slaby 
Signed-off-by: Greg Kroah-Hartman

misc: remove use of __devinit

2012-11-21T20:51:53+00:00

CONFIG_HOTPLUG is going away as an option so __devinit is no longer
needed.

Signed-off-by: Bill Pemberton 
Cc: "Michał Mirosław" 
Cc: Eric Piel 
Cc: Jiri Slaby 
Signed-off-by: Greg Kroah-Hartman