Signed-off-by: NPatrick McHardy <kaber@trash.net>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There are two possible races in handling of private_list in buffer cache.

1) When fsync_buffers_list() processes a private_list, it clears
   b_assoc_mapping and moves buffer to its private list.  Now
   drop_buffers() comes, sees a buffer is on list so it calls
   __remove_assoc_queue() which complains about b_assoc_mapping being
   cleared (as it cannot propagate possible IO error).  This race has been
   actually observed in the wild.

2) When fsync_buffers_list() processes a private_list,
   mark_buffer_dirty_inode() can be called on bh which is already on the
   private list of fsync_buffers_list().  As buffer is on some list (note
   that the check is performed without private_lock), it is not readded to
   the mapping's private_list and after fsync_buffers_list() finishes, we
   have a dirty buffer which should be on private_list but it isn't.  This
   race has not been reported, probably because most (but not all) callers
   of mark_buffer_dirty_inode() hold i_mutex and thus are serialized with
   fsync().

Fix these issues by not clearing b_assoc_map when fsync_buffers_list()
moves buffer to a dedicated list and by reinserting buffer in private_list
when it is found dirty after we have submitted buffer for IO.  We also
change the tests whether a buffer is on a private list from
!list_empty(&bh->b_assoc_buffers) to bh->b_assoc_map so that they are
single word reads and hence lockless checks are safe.
Signed-off-by: NJan Kara <jack@suse.cz>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

So we can use them for the early console like console=uart8250 or
earlycon=uart8250 or early_printk
Signed-off-by: NYinghai Lu <yinghai.lu@sun.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently, for every sysfs node, the callers will be responsible for
implementing store operation, so many many callers are doing duplicate
things to validate input, they have the same mistakes because they are
calling simple_strtol/ul/ll/uul, especially for module params, they are
just numeric, but you can echo such values as 0x1234xxx, 07777888 and
1234aaa, for these cases, module params store operation just ignores
succesive invalid char and converts prefix part to a numeric although input
is acctually invalid.

This patch tries to fix the aforementioned issues and implements
strict_strtox serial functions, kernel/params.c uses them to strictly
validate input, so module params will reject such values as 0x1234xxxx and
returns an error:

write error: Invalid argument

Any modules which export numeric sysfs node can use strict_strtox instead of
simple_strtox to reject any invalid input.

Here are some test results:

Before applying this patch:

[root@yangyi-dev /]# cat /sys/module/e1000/parameters/copybreak
4096
[root@yangyi-dev /]# echo 0x1000 > /sys/module/e1000/parameters/copybreak
[root@yangyi-dev /]# cat /sys/module/e1000/parameters/copybreak
4096
[root@yangyi-dev /]# echo 0x1000g > /sys/module/e1000/parameters/copybreak
[root@yangyi-dev /]# cat /sys/module/e1000/parameters/copybreak
4096
[root@yangyi-dev /]# echo 0x1000gggggggg > /sys/module/e1000/parameters/copybreak
[root@yangyi-dev /]# cat /sys/module/e1000/parameters/copybreak
4096
[root@yangyi-dev /]# echo 010000 > /sys/module/e1000/parameters/copybreak
[root@yangyi-dev /]# cat /sys/module/e1000/parameters/copybreak
4096
[root@yangyi-dev /]# echo 0100008 > /sys/module/e1000/parameters/copybreak
[root@yangyi-dev /]# cat /sys/module/e1000/parameters/copybreak
4096
[root@yangyi-dev /]# echo 010000aaaaa > /sys/module/e1000/parameters/copybreak
[root@yangyi-dev /]# cat /sys/module/e1000/parameters/copybreak
4096
[root@yangyi-dev /]#

After applying this patch:

[root@yangyi-dev /]# cat /sys/module/e1000/parameters/copybreak
4096
[root@yangyi-dev /]# echo 0x1000 > /sys/module/e1000/parameters/copybreak
[root@yangyi-dev /]# cat /sys/module/e1000/parameters/copybreak
4096
[root@yangyi-dev /]# echo 0x1000g > /sys/module/e1000/parameters/copybreak
-bash: echo: write error: Invalid argument
[root@yangyi-dev /]# cat /sys/module/e1000/parameters/copybreak
4096
[root@yangyi-dev /]# echo 0x1000gggggggg > /sys/module/e1000/parameters/copybreak
-bash: echo: write error: Invalid argument
[root@yangyi-dev /]# echo 010000 > /sys/module/e1000/parameters/copybreak
[root@yangyi-dev /]# echo 0100008 > /sys/module/e1000/parameters/copybreak
-bash: echo: write error: Invalid argument
[root@yangyi-dev /]# echo 010000aaaaa > /sys/module/e1000/parameters/copybreak
-bash: echo: write error: Invalid argument
[root@yangyi-dev /]# cat /sys/module/e1000/parameters/copybreak
4096
[root@yangyi-dev /]# echo -n 4096 > /sys/module/e1000/parameters/copybreak
[root@yangyi-dev /]# cat /sys/module/e1000/parameters/copybreak
4096
[root@yangyi-dev /]#

[akpm@linux-foundation.org: fix compiler warnings]
[akpm@linux-foundation.org: fix off-by-one found by tiwai@suse.de]
Signed-off-by: NYi Yang <yi.y.yang@intel.com>
Cc: Greg KH <greg@kroah.com>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix gcc warnings in getdelays.c:

Documentation/accounting/getdelays.c: In function 'task_context_switch_counts':
Documentation/accounting/getdelays.c:214: warning: format '%15lu' expects type 'long unsigned int', but argument 4 has type '__u64'
Documentation/accounting/getdelays.c:214: warning: format '%15lu' expects type 'long unsigned int', but argument 5 has type '__u64'
Documentation/accounting/getdelays.c: In function 'main':
Documentation/accounting/getdelays.c:402: warning: format '%d' expects type 'int', but argument 2 has type 'long unsigned int'
Documentation/accounting/getdelays.c: In function 'get_family_id':
Documentation/accounting/getdelays.c:171: warning: 'id' may be used uninitialized in this function

One warning is not a problem and can be dismissed:
Documentation/accounting/getdelays.c: In function 'main':
Documentation/accounting/getdelays.c:236: warning: 'cmd_type' may be used uninitialized in this function
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Acked-by: NBalbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix following warning:
WARNING: o-x86_64/kernel/built-in.o(.text+0x36d8b): Section mismatch in reference from the function enable_nonboot_cpus() to the function .cpuinit.text:_cpu_up()

enable_nonboot_cpus() are used solely from CONFIG_CONFIG_PM_SLEEP_SMP=y
and PM_SLEEP_SMP imply HOTPLUG_CPU therefore the reference
to _cpu_up() is valid.
Annotate enable_nonboot_cpus() with __ref to silence modpost.
Signed-off-by: NSam Ravnborg <sam@ravnborg.org>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since this header is exported to userspace and all the other types in the
header have been scrubbed, this brings the last straggler in line.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Following the deprecation schedule the a.out ELF interpreter support
is removed now with this patch. a.out ELF interpreters were an transition
feature for moving a.out systems to ELF, but they're unlikely to be still
needed. Pure a.out systems will still work of course. This allows to
simplify the hairy ELF loader.
Signed-off-by: NAndi Kleen <ak@suse.de>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The proper behavior to store task's pid and get this task later is to get the
struct pid pointer and get the task with the pid_task() call.

Make it for rt_mutex_waiter->deadlock_task_pid field.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

All the functions that need to lookup a task by pid in posix timers obtain
this pid from a user space, and thus this value refers to a task in the same
namespace, as the current task lives in.

So the proper behavior is to call find_task_by_vpid() here.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove the arbitrary 128 device limit for NBD.  nbds_max can now be set to
any number.  In certain scenarios where devices are used sparsely we have
run into the 128 device limit.
Signed-off-by: NPaul Clements <paul.clements@steeleye.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Instead of testing hardcoded values, use pci_match_id to reference the
pci_device_id table. Sideways, it allows easy new additions to the table.

[akpm@linux-foundation.org: remove wrongly-added semicolon]
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use pci_resource_start instead of accessing pci_dev struct internals.
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a .show_options super operation to udf.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Acked-by: NCyrill Gorcunov <gorcunov@gmail.com>
Acked-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Documentation/SubmitCheckist, please.

Cc: Hugh Dickins <hugh@veritas.com>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add .show_options super operation to tmpfs.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a .show_options super operation to spufs.

Use generic_show_options() and save the complete option string in
spufs_fill_super().
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a .show_options super operation to reiserfs.

Use generic_show_options() and save the complete option string in
reiserfs_fill_super() and reiserfs_remount().
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a .show_options super operation to ncpfs.

Small fix: add FS_BINARY_MOUNTDATA to the filesystem type flags, since
it can take binary data, as well as text (similarly to NFS).
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a .show_options super operation to isofs.

Use generic_show_options() and save the complete option string in
isofs_fill_super().
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Acked-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a .show_options super operation to hugetlbfs.

Use generic_show_options() and save the complete option string in
hugetlbfs_fill_super().
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Cc: Adam Litke <agl@us.ibm.com>
Cc: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Ken Chen <kenchen@google.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a .show_options super operation to hpfs.

Use generic_show_options() and save the complete option string in
hpfs_fill_super() and hpfs_remount_fs().

Also add a small fix: hpfs_remount_fs() should return -EINVAL on
error, instead of 1, which is not an error value.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add the "host path" option to /proc/mounts for UML hostfs filesystems.

The mount source (mnt_devname) should really be used for this, but not
easy to change now in a backward compatible way.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add blksize= option to /proc/mounts for fuseblk filesystems.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add flush option to /proc/mounts for msdos and vfat filesystems.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Acked-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add noreservation option to /proc/mounts for ext2 filesystems.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Acked-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a .show_options super operation to devpts.

Small cleanup: when parsing the "mode" option, mask with S_IALLUGO
instead of ~S_IFMT.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a .show_options super operation to capifs.

Use generic_show_options() and save the complete option string in
capifs_remount().
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Acked-by: NKarsten Keil <kkeil@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a .show_options super operation to befs.

Use generic_show_options() and save the complete option string in
befs_fill_super().
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Cc: Sergey S. Kostyliov <rathamahata@php4.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a .show_options super operation to autofs.

Use generic_show_options() and save the complete option string in
autofs_fill_super().
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Acked-by: NH. Peter Anvin <hpa@zytor.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add uid= and gid= options to /proc/mounts for autofs4 filesystems.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Acked-by: NIan Kent <raven@themaw.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a .show_options super operation to afs.

Use generic_show_options() and save the complete option string in
afs_get_sb().
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a .show_options super operation to affs.

Use generic_show_options() and save the complete option string in
affs_fill_super() and affs_remount().
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a .show_options super operation to adfs.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a new s_options field to struct super_block.  Filesystems can save
mount options passed to them in mount or remount.  It is automatically
freed when the superblock is destroyed.

A new helper function, generic_show_options() is introduced, which uses
this field to display the mount options in /proc/mounts.

Another helper function, save_mount_options() may be used by
filesystems to save the options in the super block.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This series addresses the problem of showing mount options in
/proc/mounts.

Several filesystems which use mount options, have not implemented a
.show_options superblock operation.  Several others have implemented
this callback, but have not kept it fully up to date with the parsed
options.

Q: Why do we need correct option showing in /proc/mounts?
A: We want /proc/mounts to fully replace /etc/mtab.  The reasons for
   this are:
    - unprivileged mounters won't be able to update /etc/mtab
    - /etc/mtab doesn't work with private mount namespaces
    - /etc/mtab can become out-of-sync with reality

Q: Can't this be done, so that filesystems need not bother with
   implementing a .show_mounts callback, and keeping it up to date?
A: Only in some cases.  Certain filesystems allow modification of a
   subset of options in their remount_fs method.  It is not possible
   to take this into account without knowing exactly how the
   filesystem handles options.

For the simple case (no remount or remount resets all options) the
patchset introduces two helpers:

  generic_show_options()
  save_mount_options()

These can also be used to emulate the old /etc/mtab behavior, until
proper support is added.  Even if this is not 100% correct, it's still
better than showing no options at all.

The following patches fix up most in-tree filesystems, some have been
compile tested only, some have been reviewed and acked by the
maintainer.

Table displaying status of all in-kernel filesystems:
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
legend:

  none - fs has options, but doesn't define ->show_options()
  some - fs defines ->show_options(), but some only options are shown
  good - fs shows all options
  noopt - fs does not have options
  patch - a patch will be posted
  merged - a patch has been merged by subsystem maintainer

9p          good
adfs        patch
affs        patch
afs         patch
autofs      patch
autofs4     patch
befs        patch
bfs         noopt
cifs        some
coda        noopt
configfs    noopt
cramfs      noopt
debugfs     noopt
devpts      patch
ecryptfs    good
efs         noopt
ext2        patch
ext3        good
ext4        merged
fat         patch
freevxfs    noopt
fuse        patch
fusectl	    noopt
gfs2        good
gfs2meta    noopt
hfs         good
hfsplus     good
hostfs      patch
hpfs        patch
hppfs       noopt
hugetlbfs   patch
isofs       patch
jffs2       noopt
jfs         merged
minix       noopt
msdos       ->fat
ncpfs       patch
nfs         some
nfsd        noopt
ntfs        good
ocfs2       good
ocfs2/dlmfs noopt
openpromfs  noopt
proc        noopt
qnx4        noopt
ramfs       noopt
reiserfs    patch
romfs       noopt
smbfs       good
sysfs       noopt
sysv        noopt
udf         patch
ufs         good
vfat        ->fat
xfs         good

mm/shmem.c                                    patch
drivers/oprofile/oprofilefs.c                 noopt
drivers/infiniband/hw/ipath/ipath_fs.c        noopt
drivers/misc/ibmasm/ibmasmfs.c                noopt
drivers/usb/core (usbfs)                      merged
drivers/usb/gadget (gadgetfs)                 noopt
drivers/isdn/capi/capifs.c                    patch
kernel/cpuset.c                               noopt
fs/binfmt_misc.c                              noopt
net/sunrpc/rpc_pipe.c                         noopt
arch/powerpc/platforms/cell/spufs             patch
arch/s390/hypfs                               good
ipc/mqueue.c                                  noopt
security (securityfs)                         noopt
security/selinux/selinuxfs.c                  noopt
kernel/cgroup.c                               good
security/smack/smackfs.c                      noopt

in -mm:

reiser4     some
unionfs     good
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

This patch:

Document the rules for handling mount options in the .show_options
super operation.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Per previous discussions about cleaning up ufs_fs.h, people just want
this straight up dropped from userspace export.  The only remaining
consumer (silo) has been fixed a while ago to not rely on this header.
This allows use to move it completely from include/linux/ to fs/ufs/
seeing as how the only in-kernel consumer is fs/ufs/.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Cc: Jan Kara <jack@ucw.cz>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When the conversion factor between jiffies and milli- or microseconds is
not a single multiply or divide, as for the case of HZ == 300, we currently
do a multiply followed by a divide.  The intervening result, however, is
subject to overflows, especially since the fraction is not simplified (for
HZ == 300, we multiply by 300 and divide by 1000).

This is exposed to the user when passing a large timeout to poll(), for
example.

This patch replaces the multiply-divide with a reciprocal multiplication on
32-bit platforms.  When the input is an unsigned long, there is no portable
way to do this on 64-bit platforms there is no portable way to do this
since it requires a 128-bit intermediate result (which gcc does support on
64-bit platforms but may generate libgcc calls, e.g.  on 64-bit s390), but
since the output is a 32-bit integer in the cases affected, just simplify
the multiply-divide (*3/10 instead of *300/1000).

The reciprocal multiply used can have off-by-one errors in the upper half
of the valid output range.  This could be avoided at the expense of having
to deal with a potential 65-bit intermediate result.  Since the intent is
to avoid overflow problems and most of the other time conversions are only
semiexact, the off-by-one errors were considered an acceptable tradeoff.

At Ralf Baechle's suggestion, this version uses a Perl script to compute
the necessary constants.  We already have dependencies on Perl for kernel
compiles.  This does, however, require the Perl module Math::BigInt, which
is included in the standard Perl distribution starting with version 5.8.0.
In order to support older versions of Perl, include a table of canned
constants in the script itself, and structure the script so that
Math::BigInt isn't required if pulling values from said table.

Running the script requires that the HZ value is available from the
Makefile.  Thus, this patch also adds the Kconfig variable CONFIG_HZ to the
architectures which didn't already have it (alpha, cris, frv, h8300, m32r,
m68k, m68knommu, sparc, v850, and xtensa.) It does *not* touch the sh or
sh64 architectures, since Paul Mundt has dealt with those separately in the
sh tree.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: Ralf Baechle <ralf@linux-mips.org>,
Cc: Sam Ravnborg <sam@ravnborg.org>,
Cc: Paul Mundt <lethal@linux-sh.org>,
Cc: Richard Henderson <rth@twiddle.net>,
Cc: Michael Starvik <starvik@axis.com>,
Cc: David Howells <dhowells@redhat.com>,
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>,
Cc: Hirokazu Takata <takata@linux-m32r.org>,
Cc: Geert Uytterhoeven <geert@linux-m68k.org>,
Cc: Roman Zippel <zippel@linux-m68k.org>,
Cc: William L. Irwin <sparclinux@vger.kernel.org>,
Cc: Chris Zankel <chris@zankel.net>,
Cc: H. Peter Anvin <hpa@zytor.com>,
Cc: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Makes an embedded image a bit smaller.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

do_generic_mapping_read was used by gfs2 for internals reads, but this use
of the interface was rather suboptimal (as was the whole interface) and has
been replaced by an internal helper now.  This patch kills
do_generic_mapping_read and surrounding damage in preparation of additional
cleanups for the buffered read path.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>