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2009-01-06poll: allow f_op->poll to sleepTejun Heo
f_op->poll is the only vfs operation which is not allowed to sleep. It's because poll and select implementation used task state to synchronize against wake ups, which doesn't have to be the case anymore as wait/wake interface can now use custom wake up functions. The non-sleep restriction can be a bit tricky because ->poll is not called from an atomic context and the result of accidentally sleeping in ->poll only shows up as temporary busy looping when the timing is right or rather wrong. This patch converts poll/select to use custom wake up function and use separate triggered variable to synchronize against wake up events. The only added overhead is an extra function call during wake up and negligible. This patch removes the one non-sleep exception from vfs locking rules and is beneficial to userland filesystem implementations like FUSE, 9p or peculiar fs like spufs as it's very difficult for those to implement non-sleeping poll method. While at it, make the following cosmetic changes to make poll.h and select.c checkpatch friendly. * s/type * symbol/type *symbol/ : three places in poll.h * remove blank line before EXPORT_SYMBOL() : two places in select.c Oleg: spotted missing barrier in poll_schedule_timeout() Davide: spotted missing write barrier in pollwake() Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Ron Minnich <rminnich@sandia.gov> Cc: Ingo Molnar <mingo@elte.hu> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Davide Libenzi <davidel@xmailserver.org> Cc: Brad Boyer <flar@allandria.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Roland McGrath <roland@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Davide Libenzi <davidel@xmailserver.org> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06mm: add dirty_background_bytes and dirty_bytes sysctlsDavid Rientjes
This change introduces two new sysctls to /proc/sys/vm: dirty_background_bytes and dirty_bytes. dirty_background_bytes is the counterpart to dirty_background_ratio and dirty_bytes is the counterpart to dirty_ratio. With growing memory capacities of individual machines, it's no longer sufficient to specify dirty thresholds as a percentage of the amount of dirtyable memory over the entire system. dirty_background_bytes and dirty_bytes specify quantities of memory, in bytes, that represent the dirty limits for the entire system. If either of these values is set, its value represents the amount of dirty memory that is needed to commence either background or direct writeback. When a `bytes' or `ratio' file is written, its counterpart becomes a function of the written value. For example, if dirty_bytes is written to be 8096, 8K of memory is required to commence direct writeback. dirty_ratio is then functionally equivalent to 8K / the amount of dirtyable memory: dirtyable_memory = free pages + mapped pages + file cache dirty_background_bytes = dirty_background_ratio * dirtyable_memory -or- dirty_background_ratio = dirty_background_bytes / dirtyable_memory AND dirty_bytes = dirty_ratio * dirtyable_memory -or- dirty_ratio = dirty_bytes / dirtyable_memory Only one of dirty_background_bytes and dirty_background_ratio may be specified at a time, and only one of dirty_bytes and dirty_ratio may be specified. When one sysctl is written, the other appears as 0 when read. The `bytes' files operate on a page size granularity since dirty limits are compared with ZVC values, which are in page units. Prior to this change, the minimum dirty_ratio was 5 as implemented by get_dirty_limits() although /proc/sys/vm/dirty_ratio would show any user written value between 0 and 100. This restriction is maintained, but dirty_bytes has a lower limit of only one page. Also prior to this change, the dirty_background_ratio could not equal or exceed dirty_ratio. This restriction is maintained in addition to restricting dirty_background_bytes. If either background threshold equals or exceeds that of the dirty threshold, it is implicitly set to half the dirty threshold. Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: David Rientjes <rientjes@google.com> Cc: Andrea Righi <righi.andrea@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-05ocfs2: add mount option and Kconfig option for aclTiger Yang
This patch adds the Kconfig option "CONFIG_OCFS2_FS_POSIX_ACL" and mount options "acl" to enable acls in Ocfs2. Signed-off-by: Tiger Yang <tiger.yang@oracle.com> Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-01-02Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6Linus Torvalds
* '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 ...
2009-01-02Document usage of multiple-instances of devptsSukadev Bhattiprolu
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>
2008-12-31kill ->dir_notify()Al Viro
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>
2008-12-31fix f_count description in Documentation/filesystems/files.txtEric Dumazet
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>
2008-12-31correct wrong function name of d_put in kernel document and source commentZhaolei
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>
2008-12-31UBIFS: fix numerous spelling mistakesArtem Bityutskiy
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-29[XFS] Fix merge failuresLachlan McIlroy
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>
2008-12-23Merge branches 'x86/apic', 'x86/cleanups', 'x86/cpufeature', ↵Ingo Molnar
'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
2008-12-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6Lachlan McIlroy
2008-12-03UBIFS: introduce compression mount optionsArtem Bityutskiy
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>
2008-12-01epoll: introduce resource usage limitsDavide Libenzi
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>
2008-12-01ocfs2: Small documentation updateMark Fasheh
Remove some features from the "not-supported" list that are actually supported now. Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-11-30Trivial Documentation/filesystems/ramfs-rootfs-initramfs.txt fixfrans
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>
2008-11-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6Lachlan McIlroy
2008-11-12DOC: update xip method infoMarco Stornelli
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>
2008-11-07Merge branch 'master' of git://oss.sgi.com:8090/xfs/linux-2.6Niv Sardi
2008-11-06fat: Fix ATTR_RO for directoryOGAWA Hirofumi
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>
2008-11-06fat: document additional vfat mount optionsBart Trojanowski
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>
2008-10-30fs: remove prepare_write/commit_writeNick Piggin
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>
2008-10-30x86, nmi-watchdog: update procfs nmi_watchdog file documentation v2Aristeu Rozanski
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[XFS] remove restricted chown parameter from xfs linuxTim Shimmin
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>
2008-10-20Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6Linus Torvalds
* '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 ...
2008-10-20ext3: add an option to control error handling on file dataHidehiro Kawai
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>
2008-10-20documentation: clarify dirty_ratio and dirty_background_ratio descriptionAndrea Righi
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>
2008-10-20coredump_filter: add hugepage dumpingKOSAKI Motohiro
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>
2008-10-17ext4: Update Documentation/filesystems/ext4.txtDiego Calleja
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>
2008-10-16autofs4: device node ioctl documentationIan Kent
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>
2008-10-16Document panic_on_unrecovered_nmi sysctlBernhard Walle
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>
2008-10-16Remove Andrew Morton's http://www.zip.com.au/~akpm/FD Cami
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>
2008-10-16doc: typo in Documentation/filesystems/nfsroot.txtShane McDonald
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>
2008-10-16Fix Documentation/filesystems/ramfs-rootfs-initramfs.txtfrans
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>
2008-10-13ocfs2: Documentation update for user_xattr / nouser_xattr mount optionsMark Fasheh
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-10-13ocfs2: Add the 'inode64' mount option.Joel Becker
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>
2008-10-13Merge branch 'proc' of ↵Linus Torvalds
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
2008-10-10ext4: add an option to control error handling on file dataHidehiro Kawai
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>
2008-10-10ext4: Rename ext4dev to ext4Theodore Ts'o
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>
2008-10-10proc: remove kernel.maps_protectAlexey Dobriyan
After commit 831830b5a2b5d413407adf380ef62fe17d6fcbf2 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>
2008-10-08vfs: vfs-level fiemap interfaceMark Fasheh
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
2008-10-09ext4: Use readahead when reading an inode from the inode tableTheodore Ts'o
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>
2008-10-09ext4: Improve the documentation for ext4's /proc tunablesTheodore Ts'o
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Alex Tomas <bzzz@sun.com> Cc: Andreas Dilger <adilger@sun.com>
2008-09-30UBIFS: add no_chk_data_crc mount optionAdrian Hunter
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>
2008-09-30UBIFS: add bulk-read facilityAdrian Hunter
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>
2008-09-13coredump_filter: add description of bit 4Hidehiro Kawai
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>
2008-09-09update Documentation/filesystems/Locking for 2.6.27 changesChristoph Hellwig
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>
2008-09-02ipc: document the new auto_msgmni proc fileNadia Derbey
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>
2008-09-02NTFS: update homepageAdrian Bunk
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>
2008-08-22Merge branch 'for_linus' of ↵Linus Torvalds
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