Commit Graph

327 Commits

Author SHA1 Message Date
Linus Torvalds 8e3bda0863 Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6
* 'linux-next' of git://git.infradead.org/ubifs-2.6: (33 commits)
  UBIFS: add more useful debugging prints
  UBIFS: print debugging messages properly
  UBIFS: fix numerous spelling mistakes
  UBIFS: allow mounting when short of space
  UBIFS: fix writing uncompressed files
  UBIFS: fix checkpatch.pl warnings
  UBIFS: fix sparse warnings
  UBIFS: simplify make_free_space
  UBIFS: do not lie about used blocks
  UBIFS: restore budg_uncommitted_idx
  UBIFS: always commit on unmount
  UBIFS: use ubi_sync
  UBIFS: always commit in sync_fs
  UBIFS: fix file-system synchronization
  UBIFS: fix constants initialization
  UBIFS: avoid unnecessary calculations
  UBIFS: re-calculate min_idx_size after the commit
  UBIFS: use nicer 64-bit math
  UBIFS: fix available blocks count
  UBIFS: various comment improvements and fixes
  ...
2009-01-02 15:57:47 -08:00
Sukadev Bhattiprolu 784c4d8b1b Document usage of multiple-instances of devpts
Changelog [v2]:
	- Add note indicating strict isolation is not possible unless all
	  mounts of devpts use the 'newinstance' mount option.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:36 -08:00
Al Viro 6badd79bd0 kill ->dir_notify()
Remove the hopelessly misguided ->dir_notify().  The only instance (cifs)
has been broken by design from the very beginning; the objects it creates
are never destroyed, keep references to struct file they can outlive, nothing
that could possibly evict them exists on close(2) path *and* no locking
whatsoever is done to prevent races with close(), should the previous, er,
deficiencies someday be dealt with.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:43 -05:00
Eric Dumazet fd659fd627 fix f_count description in Documentation/filesystems/files.txt
Documentation/filesystems/files.txt was not updated when
f_count became an atomic_long_t.
atomic_long_inc_not_zero() is now used instead of atomic_inc_not_zero()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:42 -05:00
Zhaolei be42c4c433 correct wrong function name of d_put in kernel document and source comment
no function named d_put(), it should be dput().

Impact: fix document and comment, no functionality changed

Signed-off-by: Zhao Lei <zhaolei@cn.fuijtsu.com>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:40 -05:00
Artem Bityutskiy 80736d41f8 UBIFS: fix numerous spelling mistakes
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-31 14:13:25 +02:00
Lachlan McIlroy 0a8c5395f9 [XFS] Fix merge failures
Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

Conflicts:

	fs/xfs/linux-2.6/xfs_cred.h
	fs/xfs/linux-2.6/xfs_globals.h
	fs/xfs/linux-2.6/xfs_ioctl.c
	fs/xfs/xfs_vnodeops.h

Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-12-29 16:47:18 +11:00
Ingo Molnar fa623d1b02 Merge branches 'x86/apic', 'x86/cleanups', 'x86/cpufeature', 'x86/crashdump', 'x86/debug', 'x86/defconfig', 'x86/detect-hyper', 'x86/doc', 'x86/dumpstack', 'x86/early-printk', 'x86/fpu', 'x86/idle', 'x86/io', 'x86/memory-corruption-check', 'x86/microcode', 'x86/mm', 'x86/mtrr', 'x86/nmi-watchdog', 'x86/pat2', 'x86/pci-ioapic-boot-irq-quirks', 'x86/ptrace', 'x86/quirks', 'x86/reboot', 'x86/setup-memory', 'x86/signal', 'x86/sparse-fixes', 'x86/time', 'x86/uv' and 'x86/xen' into x86/core 2008-12-23 16:27:23 +01:00
Lachlan McIlroy 14d676f56f Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 2008-12-05 15:27:43 +11:00
Artem Bityutskiy 553dea4dd5 UBIFS: introduce compression mount options
It is very handy to be able to change default UBIFS compressor
via mount options. Introduce -o compr=<name> mount option support.
Currently only "none", "lzo" and "zlib" compressors are supported.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-03 13:14:05 +02:00
Davide Libenzi 7ef9964e6d epoll: introduce resource usage limits
It has been thought that the per-user file descriptors limit would also
limit the resources that a normal user can request via the epoll
interface.  Vegard Nossum reported a very simple program (a modified
version attached) that can make a normal user to request a pretty large
amount of kernel memory, well within the its maximum number of fds.  To
solve such problem, default limits are now imposed, and /proc based
configuration has been introduced.  A new directory has been created,
named /proc/sys/fs/epoll/ and inside there, there are two configuration
points:

  max_user_instances = Maximum number of devices - per user

  max_user_watches   = Maximum number of "watched" fds - per user

The current default for "max_user_watches" limits the memory used by epoll
to store "watches", to 1/32 of the amount of the low RAM.  As example, a
256MB 32bit machine, will have "max_user_watches" set to roughly 90000.
That should be enough to not break existing heavy epoll users.  The
default value for "max_user_instances" is set to 128, that should be
enough too.

This also changes the userspace, because a new error code can now come out
from EPOLL_CTL_ADD (-ENOSPC).  The EMFILE from epoll_create() was already
listed, so that should be ok.

[akpm@linux-foundation.org: use get_current_user()]
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: <stable@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Reported-by: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-01 19:55:24 -08:00
Mark Fasheh a2eee69b81 ocfs2: Small documentation update
Remove some features from the "not-supported" list that are actually
supported now.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-12-01 14:46:49 -08:00
frans 1838e39214 Trivial Documentation/filesystems/ramfs-rootfs-initramfs.txt fix
A very minor patch on ramfs-rootfs-initramfs.txt: update the location
where CONFIG_INITRAMFS_SOURCE lives in menuconfig

Signed-off-by: Frans Meulenbroeks <fransmeulenbroeks@gmail.com>
Acked-by: Rob Landley <rob@landley.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-30 11:40:56 -08:00
Lachlan McIlroy b5a20aa265 Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 2008-11-28 15:23:52 +11:00
Marco Stornelli 084c304980 DOC: update xip method info
xip documentation updated:
- change "get_xip_page" to "get_xip_mem";
- explain changed function parameters

Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-12 17:17:17 -08:00
Niv Sardi dcd7b4e5c0 Merge branch 'master' of git://oss.sgi.com:8090/xfs/linux-2.6 2008-11-07 15:07:12 +11:00
OGAWA Hirofumi dfc209c006 fat: Fix ATTR_RO for directory
FAT has the ATTR_RO (read-only) attribute. But on Windows, the ATTR_RO
of the directory will be just ignored actually, and is used by only
applications as flag. E.g. it's setted for the customized folder by
Explorer.

http://msdn2.microsoft.com/en-us/library/aa969337.aspx

This adds "rodir" option. If user specified it, ATTR_RO is used as
read-only flag even if it's the directory. Otherwise, inode->i_mode
is not used to hold ATTR_RO (i.e. fat_mode_can_save_ro() returns 0).

Signed-off-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>
2008-11-06 15:41:21 -08:00
Bart Trojanowski 8986ab5963 fat: document additional vfat mount options
While debugging a sync mount regression on vfat I noticed that there were
mount options parsed by the driver that were not documented.

[hirofumi@mail.parknet.co.jp: fix some parts]
Signed-off-by: Bart Trojanowski <bart@jukie.net>
Signed-off-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>
2008-11-06 15:41:20 -08:00
Nick Piggin 4e02ed4b4a fs: remove prepare_write/commit_write
Nothing uses prepare_write or commit_write. Remove them from the tree
completely.

[akpm@linux-foundation.org: schedule simple_prepare_write() for unexporting]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-30 11:38:45 -07:00
Aristeu Rozanski 8a1c8eb75b x86, nmi-watchdog: update procfs nmi_watchdog file documentation v2
Impact: improve documentation

This patch updates the /proc/sys/kernel/nmi_watchdog documentation.
Updated: included Randy Dunlap's corrections.

Signed-off-by: Aristeu Rozanski <aris@redhat.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-30 19:07:04 +01:00
Tim Shimmin f3f0d7b026 [XFS] remove restricted chown parameter from xfs linux
On Linux all filesystems are supposed to be operating under Posix'
restricted chown. Restricted chown means it restricts chown to the owner
unless you have CAP_FOWNER.

NOTE: that 2 files outside of fs/xfs have been modified too for this
change.

Reviewed-by: Dave Chinner <david@fromorbit.com>

SGI-PV: 988919

SGI-Modid: 2.6.x-xfs-melb:linux:32413b

Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
2008-10-30 18:30:09 +11:00
Linus Torvalds 396b122f6a Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6
* 'linux-next' of git://git.infradead.org/ubifs-2.6: (25 commits)
  UBIFS: fix ubifs_compress commentary
  UBIFS: amend printk
  UBIFS: do not read unnecessary bytes when unpacking bits
  UBIFS: check buffer length when scanning for LPT nodes
  UBIFS: correct condition to eliminate unecessary assignment
  UBIFS: add more debugging messages for LPT
  UBIFS: fix bulk-read handling uptodate pages
  UBIFS: improve garbage collection
  UBIFS: allow for sync_fs when read-only
  UBIFS: commit on sync_fs
  UBIFS: correct comment for commit_on_unmount
  UBIFS: update dbg_dump_inode
  UBIFS: fix commentary
  UBIFS: fix races in bit-fields
  UBIFS: ensure data read beyond i_size is zeroed out correctly
  UBIFS: correct key comparison
  UBIFS: use bit-fields when possible
  UBIFS: check data CRC when in error state
  UBIFS: improve znode splitting rules
  UBIFS: add no_chk_data_crc mount option
  ...
2008-10-20 09:19:03 -07:00
Hidehiro Kawai 0e4fb5e283 ext3: add an option to control error handling on file data
If the journal doesn't abort when it gets an IO error in file data blocks,
the file data corruption will spread silently.  Because most of
applications and commands do buffered writes without fsync(), they don't
notice the IO error.  It's scary for mission critical systems.  On the
other hand, if the journal aborts whenever it gets an IO error in file
data blocks, the system will easily become inoperable.  So this patch
introduces a filesystem option to determine whether it aborts the journal
or just call printk() when it gets an IO error in file data.

If you mount a ext3 fs with data_err=abort option, it aborts on file data
write error.  If you mount it with data_err=ignore, it doesn't abort, just
call printk().  data_err=ignore is the default.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Jan Kara <jack@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:37 -07:00
Andrea Righi 7a6560e025 documentation: clarify dirty_ratio and dirty_background_ratio description
The current documentation of dirty_ratio and dirty_background_ratio is a
bit misleading.

In the documentation we say that they are "a percentage of total system
memory", but the current page writeback policy, intead, is to apply the
percentages to the dirtyable memory, that means free pages + reclaimable
pages.

Better to be more explicit to clarify this concept.

Signed-off-by: Andrea Righi <righi.andrea@gmail.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:32 -07:00
KOSAKI Motohiro e575f111dc coredump_filter: add hugepage dumping
Presently hugepage's vma has a VM_RESERVED flag in order not to be
swapped.  But a VM_RESERVED vma isn't core dumped because this flag is
often used for some kernel vmas (e.g.  vmalloc, sound related).

Thus hugepages are never dumped and it can't be debugged easily.  Many
developers want hugepages to be included into core-dump.

However, We can't read generic VM_RESERVED area because this area is often
IO mapping area.  then these area reading may change device state.  it is
definitly undesiable side-effect.

So adding a hugepage specific bit to the coredump filter is better.  It
will be able to hugepage core dumping and doesn't cause any side-effect to
any i/o devices.

In additional, libhugetlb use hugetlb private mapping pages as anonymous
page.  Then, hugepage private mapping pages should be core dumped by
default.

Then, /proc/[pid]/core_dump_filter has two new bits.

 - bit 5 mean hugetlb private mapping pages are dumped or not. (default: yes)
 - bit 6 mean hugetlb shared mapping pages are dumped or not.  (default: no)

I tested by following method.

% ulimit -c unlimited
% ./crash_hugepage  50
% ./crash_hugepage  50  -p
% ls -lh
% gdb ./crash_hugepage core
%
% echo 0x43 > /proc/self/coredump_filter
% ./crash_hugepage  50
% ./crash_hugepage  50  -p
% ls -lh
% gdb ./crash_hugepage core

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/mman.h>
#include <string.h>

#include "hugetlbfs.h"

int main(int argc, char** argv){
	char* p;
	int ch;
	int mmap_flags = MAP_SHARED;
	int fd;
	int nr_pages;

	while((ch = getopt(argc, argv, "p")) != -1) {
		switch (ch) {
		case 'p':
			mmap_flags &= ~MAP_SHARED;
			mmap_flags |= MAP_PRIVATE;
			break;
		default:
			/* nothing*/
			break;
		}
	}
	argc -= optind;
	argv += optind;

	if (argc == 0){
		printf("need # of pages\n");
		exit(1);
	}

	nr_pages = atoi(argv[0]);
	if (nr_pages < 2) {
		printf("nr_pages must >2\n");
		exit(1);
	}

	fd = hugetlbfs_unlinked_fd();
	p = mmap(NULL, nr_pages * gethugepagesize(),
		 PROT_READ|PROT_WRITE, mmap_flags, fd, 0);

	sleep(2);

	*(p + gethugepagesize()) = 1; /* COW */
	sleep(2);

	/* crash! */
	*(int*)0 = 1;

	return 0;
}

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Kawai Hidehiro <hidehiro.kawai.ez@hitachi.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: William Irwin <wli@holomorphy.com>
Cc: Adam Litke <agl@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20 08:52:32 -07:00
Diego Calleja 22359f5745 ext4: Update Documentation/filesystems/ext4.txt
Since Ext4 is supposed to be stable in 2.6.28-rc, ext4's documentation
file should be updated.

[ More updates also added by Theodore Ts'o. ]

Signed-off-by: Diego Calleja <diegocg@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-17 09:15:14 -04:00
Ian Kent 4b22ff1341 autofs4: device node ioctl documentation
Add documentation for the miscellaneous device module of autofs4.

Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:39 -07:00
Bernhard Walle 22b8ab66de Document panic_on_unrecovered_nmi sysctl
This adds "panic_on_unrecovered_nmi" sysctl to
Documentation/filesystems/proc.txt. The text is mainly taken from
http://readlist.com/lists/vger.kernel.org/linux-kernel/43/217998.html.

Signed-off-by: Bernhard Walle <bwalle@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:32 -07:00
FD Cami 2223c65103 Remove Andrew Morton's http://www.zip.com.au/~akpm/
Remove Andrew Morton's http://www.zip.com.au/~akpm/ urls, update to new
ones when necessary, delete references otherwise.

There are still instances of that living in:
Documentation/zh_CN/HOWTO
Documentation/zh_CN/SubmittingPatches
Documentation/ko_KR/HOWTO
Documentation/ja_JP/SubmittingPatches

Signed-off-by: Francois Cami <francois.cami@free.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:32 -07:00
Shane McDonald 1c828320d2 doc: typo in Documentation/filesystems/nfsroot.txt
Add a missing word to the explanation of the purpose of the zdisk and
bzdisk make targets.

Signed-off-by: Shane McDonald <mcdonald.shane@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:31 -07:00
frans dd1c53a64a Fix Documentation/filesystems/ramfs-rootfs-initramfs.txt
First a file hello.c is created, then the file hello2.c is compiled.
Change this to hello.c

Signed-off-by: Frans Meulenbroeks <fransmeulenbroeks@gmail.com>
Signed-off-by: Rob Landley <rob@landley.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:30 -07:00
Mark Fasheh 696b55d768 ocfs2: Documentation update for user_xattr / nouser_xattr mount options
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-10-13 17:02:44 -07:00
Joel Becker 12462f1d9f ocfs2: Add the 'inode64' mount option.
Now that ocfs2 limits inode numbers to 32bits, add a mount option to
disable the limit.  This parallels XFS.  64bit systems can handle the
larger inode numbers.

[ Added description of inode64 mount option in ocfs2.txt. --Mark ]

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-10-13 16:57:08 -07:00
Linus Torvalds 20272c8994 Merge branch 'proc' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc
* 'proc' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc:
  proc: remove kernel.maps_protect
  proc: remove now unneeded ADDBUF macro
  [PATCH] proc: show personality via /proc/pid/personality
  [PATCH] signal, procfs: some lock_task_sighand() users do not need rcu_read_lock()
  proc: move PROC_PAGE_MONITOR to fs/proc/Kconfig
  proc: make grab_header() static
  proc: remove unused get_dma_list()
  proc: remove dummy vmcore_open()
  proc: proc_sys_root tweak
  proc: fix return value of proc_reg_open() in "too late" case

Fixed up trivial conflict in removed file arch/sparc/include/asm/dma_32.h
2008-10-13 10:04:04 -07:00
Hidehiro Kawai 5bf5683a33 ext4: add an option to control error handling on file data
If the journal doesn't abort when it gets an IO error in file data
blocks, the file data corruption will spread silently.  Because
most of applications and commands do buffered writes without fsync(),
they don't notice the IO error.  It's scary for mission critical
systems.  On the other hand, if the journal aborts whenever it gets
an IO error in file data blocks, the system will easily become
inoperable.  So this patch introduces a filesystem option to
determine whether it aborts the journal or just call printk() when
it gets an IO error in file data.

If you mount an ext4 fs with data_err=abort option, it aborts on file
data write error.  If you mount it with data_err=ignore, it doesn't
abort, just call printk().  data_err=ignore is the default.

Here is the corresponding patch of the ext3 version:
http://kerneltrap.org/mailarchive/linux-kernel/2008/9/9/3239374

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2008-10-10 22:12:43 -04:00
Theodore Ts'o 03010a3350 ext4: Rename ext4dev to ext4
The ext4 filesystem is getting stable enough that it's time to drop
the "dev" prefix.  Also remove the requirement for the TEST_FILESYS
flag.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-10 20:02:48 -04:00
Alexey Dobriyan 3bbfe05967 proc: remove kernel.maps_protect
After commit 831830b5a2 aka
"restrict reading from /proc/<pid>/maps to those who share ->mm or can ptrace"
sysctl stopped being relevant because commit moved security checks from ->show
time to ->start time (mm_for_maps()).

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Kees Cook <kees.cook@canonical.com>
2008-10-10 04:24:51 +04:00
Mark Fasheh c4b929b85b vfs: vfs-level fiemap interface
Basic vfs-level fiemap infrastructure, which sets up a new ->fiemap
inode operation.

Userspace can get extent information on a file via fiemap ioctl. As input,
the fiemap ioctl takes a struct fiemap which includes an array of struct
fiemap_extent (fm_extents). Size of the extent array is passed as
fm_extent_count and number of extents returned will be written into
fm_mapped_extents. Offset and length fields on the fiemap structure
(fm_start, fm_length) describe a logical range which will be searched for
extents. All extents returned will at least partially contain this range.
The actual extent offsets and ranges returned will be unmodified from their
offset and range on-disk.

The fiemap ioctl returns '0' on success. On error, -1 is returned and errno
is set. If errno is equal to EBADR, then fm_flags will contain those flags
which were passed in which the kernel did not understand. On all other
errors, the contents of fm_extents is undefined.

As fiemap evolved, there have been many authors of the vfs patch. As far as
I can tell, the list includes:
Kalpak Shah <kalpak.shah@sun.com>
Andreas Dilger <adilger@sun.com>
Eric Sandeen <sandeen@redhat.com>
Mark Fasheh <mfasheh@suse.com>

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: linux-api@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
2008-10-08 19:44:18 -04:00
Theodore Ts'o 240799cdf2 ext4: Use readahead when reading an inode from the inode table
With modern hard drives, reading 64k takes roughly the same time as
reading a 4k block.  So request readahead for adjacent inode table
blocks to reduce the time it takes when iterating over directories
(especially when doing this in htree sort order) in a cold cache case.
With this patch, the time it takes to run "git status" on a kernel
tree after flushing the caches via "echo 3 > /proc/sys/vm/drop_caches"
is reduced by 21%.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2008-10-09 23:53:47 -04:00
Theodore Ts'o 37515facd0 ext4: Improve the documentation for ext4's /proc tunables
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alex Tomas <bzzz@sun.com>
Cc: Andreas Dilger <adilger@sun.com>
2008-10-09 23:21:54 -04:00
Adrian Hunter 2953e73f1c UBIFS: add no_chk_data_crc mount option
UBIFS read performance can be improved by skipping the CRC
check when data nodes are read.  This option can be used if
the underlying media is considered to be highly reliable.
Note that CRCs are always checked for metadata.

Read speed on Arm platform with OneNAND goes from 19 MiB/s
to 27 MiB/s with data CRC checking disabled.

Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
2008-09-30 11:12:56 +03:00
Adrian Hunter 4793e7c5e1 UBIFS: add bulk-read facility
Some flash media are capable of reading sequentially at faster rates.
UBIFS bulk-read facility is designed to take advantage of that, by
reading in one go consecutive data nodes that are also located
consecutively in the same LEB.

Read speed on Arm platform with OneNAND goes from 17 MiB/s to
19 MiB/s.

Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
2008-09-30 11:12:56 +03:00
Hidehiro Kawai b261dfea48 coredump_filter: add description of bit 4
There is no description of bit 4 of coredump_filter in the
documentation.  This patch adds it.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-13 14:41:51 -07:00
Christoph Hellwig adaae7215e update Documentation/filesystems/Locking for 2.6.27 changes
In the 2.6.27 circle ->fasync lost the BKL, and the last remaining
->open variant that takes the BKL is also gone.  ->get_sb and ->kill_sb
didn't have BKL forever, so updated the entries while we're at that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-09 11:51:15 -07:00
Nadia Derbey 61e55d0576 ipc: document the new auto_msgmni proc file
Update Documentation/filesystems/proc.txt: it describes the file
auto_msgmni intoduced to enable/disable msgmni automatic recomputing upon
memory add/remove (see thread http://lkml.org/lkml/2008/7/4/27).  Also
added a description for msgmni (this filex is only listed in
Documentation/sysctl/kernel.txt).

Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-02 19:21:39 -07:00
Adrian Bunk 169ccbd44e NTFS: update homepage
Update the location of the NTFS homepage in several files.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-02 19:21:37 -07:00
Linus Torvalds ee26562772 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: Update documentation to remind users to update mke2fs.conf
  ext4: Fix small file fragmentation
  ext4: Initialize writeback_index to 0 when allocating a new inode
  ext4: make sure ext4_has_free_blocks returns 0 for ENOSPC
  ext4: journal credit fix for the delayed allocation's writepages() function
  ext4: Rework the ext4_da_writepages() function
  ext4: journal credits reservation fixes for DIO, fallocate
  ext4: journal credits reservation fixes for extent file writepage
  ext4: journal credits calulation cleanup and fix for non-extent writepage
  ext4: Fix bug where we return ENOSPC even though we have plenty of inodes
  ext4: don't try to resize if there are no reserved gdt blocks left
  ext4: Use ext4_discard_reservations instead of mballoc-specific call
  ext4: Fix ext4_dx_readdir hash collision handling
  ext4: Fix delalloc release block reservation for truncate
  ext4: Fix potential truncate BUG due to i_prealloc_list being non-empty
  ext4: Handle unwritten extent properly with delayed allocation
2008-08-22 08:37:07 -07:00
Sebastian Siewior 2e244d0836 Documentation: fix typo in ubifs.txt
Signed-off-by: Sebastian Siewior <bigeasy@linutronix.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-08-13 11:14:54 +03:00
Randy Dunlap 3794f3e812 docsrc: build Documentation/ sources
Currently source files in the Documentation/ sub-dir can easily bit-rot
since they are not generally buildable, either because they are hidden in
text files or because there are no Makefile rules for them.  This needs to
be fixed so that the source files remain usable and good examples of code
instead of bad examples.

Add the ability to build source files that are in the Documentation/ dir.
Add to Kconfig as "BUILD_DOCSRC" config symbol.

Use "CONFIG_BUILD_DOCSRC=1 make ..." to build objects from the
Documentation/ sources.  Or enable BUILD_DOCSRC in the *config system.
However, this symbol depends on HEADERS_CHECK since the header files need
to be installed (for userspace builds).

Built (using cross-tools) for x86-64, i386, alpha, ia64, sparc32,
sparc64, powerpc, sh, m68k, & mips.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-12 16:07:30 -07:00
Jan Kara 866c36637f quota: documentation for sending "below quota" messages via netlink and tiny doc update
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-12 16:07:27 -07:00