summaryrefslogtreecommitdiff
path: root/Documentation
AgeCommit message (Collapse)Author
2011-02-17kbuild, mtd, net: a few comment typo fixes and rewordingGilles Espinasse
Signed-off-by: Gilles Espinasse <g.esp@free.fr> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-02-17memcg: clarify use_hierarchy documentationGreg Thelen
The memcg code does not allow changing memory.use_hierarchy if the parent cgroup has enabled use_hierarchy. Update documentation to match the code. Signed-off-by: Greg Thelen <gthelen@google.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-02-15doc: Fix numbering of KVM API description sectionsPaul Bolle
Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Reviewed-by: Jesper Juhl <jj@chaosbits.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-02-15Merge branch 'master' into for-nextJiri Kosina
2011-02-13Merge branch 'spi/merge' of git://git.secretlab.ca/git/linux-2.6Linus Torvalds
* 'spi/merge' of git://git.secretlab.ca/git/linux-2.6: devicetree-discuss is moderated for non-subscribers MAINTAINERS: Add entry for GPIO subsystem dt: add documentation of ARM dt boot interface dt: Remove obsolete description of powerpc boot interface dt: Move device tree documentation out of powerpc directory spi/spi_sh_msiof: fix wrong address calculation, which leads to an Oops
2011-02-11Documentation: default_message_level is a typoPaul Bolle
It's default_message_loglevel, not default_message_level. Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-02-06Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6: ALSA: use linux/io.h to fix compile warnings ALSA: hda - Fix memory leaks in conexant jack arrays ASoC: CX20442: fix NULL pointer dereference ASoC: Amstrad Delta: fix const related build error ALSA: oxygen: fix output routing on Xonar DG sound: silent echo'ed messages in Makefile ASoC: Fix mask/val_mask confusion snd_soc_dapm_put_volsw() ASoC: DaVinci: fix kernel panic due to uninitialized platform_data ALSA: HDA: Fix microphone(s) on Lenovo Edge 13 ASoC: Fix module refcount for auxiliary devices ALSA: HDA: cxt5066 - Use asus model for Asus U50F, select correct SPDIF output ALSA: HDA: Add a new model "asus" for Conexant 5066/205xx ALSA: HDA: Refactor some redundant code for Conexant 5066/205xx
2011-02-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (68 commits) net: can: janz-ican3: world-writable sysfs termination file net: can: at91_can: world-writable sysfs files MAINTAINERS: update email ids of the be2net driver maintainers. bridge: Don't put partly initialized fdb into hash r8169: prevent RxFIFO induced loops in the irq handler. r8169: RxFIFO overflow oddities with 8168 chipsets. r8169: use RxFIFO overflow workaround for 8168c chipset. include/net/genetlink.h: Allow genlmsg_cancel to accept a NULL argument net: Provide compat support for SIOCGETMIFCNT_IN6 and SIOCGETSGCNT_IN6. net: Support compat SIOCGETVIFCNT ioctl in ipv4. net: Fix bug in compat SIOCGETSGCNT handling. niu: Fix races between up/down and get_stats. tcp_ecn is an integer not a boolean atl1c: Add missing PCI device ID s390: Fix possibly wrong size in strncmp (smsgiucv) s390: Fix wrong size in memcmp (netiucv) qeth: allow OSA CHPARM change in suspend state qeth: allow HiperSockets framesize change in suspend qeth: add more strict MTU checking qeth: show new mac-address if its setting fails ...
2011-02-03Merge branch 'sched-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: sched: Fix update_curr_rt() sched, docs: Update schedstats documentation to version 15
2011-02-02memsw: deprecate noswapaccount kernel parameter and schedule it for removalMichal Hocko
noswapaccount couldn't be used to control memsw for both on/off cases so we have added swapaccount[=0|1] parameter. This way we can turn the feature in two ways noswapaccount resp. swapaccount=0. We have kept the original noswapaccount but I think we should remove it after some time as it just makes more command line parameters without any advantages and also the code to handle parameters is uglier if we want both parameters. Signed-off-by: Michal Hocko <mhocko@suse.cz> Requested-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-02tcp_ecn is an integer not a booleanPeter Chubb
There was some confusion at LCA as to why the sysctl tcp_ecn took one of three values when it was documented as a Boolean. This patch fixes the documentation. Signed-off-by: Peter Chubb <peter.chubb@nicta.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-01sched, docs: Update schedstats documentation to version 15Javi Merino
Version 15 of schedstats was introduced in: 67aa0f767af4: sched: remove unused fields from struct rq and removed three unused counters in sched_yield(). Update the documentation. Signed-off-by: Javi Merino <cibervicho@gmail.com> Cc: henrix@sapo.pt Cc: rdunlap@xenotime.net Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <1296515496-8229-1-git-send-email-cibervicho@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-01-31dt: add documentation of ARM dt boot interfaceGrant Likely
v3: added details to Documentation/arm/Booting Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-01-31dt: Remove obsolete description of powerpc boot interfaceGrant Likely
32 and 64 bit powerpc support has been merged for a while now, but the booting-without-of.txt document still describes 32 bit as not supporting multiplatform, which is no longer true. This patch fixes the documentation. Also remove references to powerpc-specific details outside of section I in preparation to add details for other architectures. v3: cleaned up a lot more powerpc-isms and updated text to reflect current usage conventions. Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-01-31dt: Move device tree documentation out of powerpc directoryGrant Likely
The device tree is used by more than just PowerPC. Make the documentation directory available to all. v2: reorganized files while moving to create arch and driver specific directories. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2011-01-31NTFS: Fix invalid pointer dereference in ntfs_mft_record_alloc().Anton Altaparmakov
In ntfs_mft_record_alloc() when mapping the new extent mft record with map_extent_mft_record() we overwrite @m with the return value and on error, we then try to use the old @m but that is no longer there as @m now contains an error code instead so we crash when dereferencing the error code as if it were a pointer. The simple fix is to use a temporary variable to store the return value thus preserving the original @m for later use. This is a backport from the commercial Tuxera-NTFS driver and is well tested... Thanks go to Julia Lawall for pointing this out (whilst I had fixed it in the commercial driver I had failed to fix it in the Linux kernel). Signed-off-by: Anton Altaparmakov <anton@tuxera.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (43 commits) bnx2: Eliminate AER error messages on systems not supporting it cnic: Fix big endian bug xfrm6: Don't forget to propagate peer into ipsec route. tg3: Use new VLAN code bonding: update documentation - alternate configuration. TCP: fix a bug that triggers large number of TCP RST by mistake MAINTAINERS: remove Reinette Chatre as iwlwifi maintainer rt2x00: add device id for windy31 usb device mac80211: fix a crash in ieee80211_beacon_get_tim on change_interface ipv6: Revert 'administrative down' address handling changes. textsearch: doc - fix spelling in lib/textsearch.c. USB NET KL5KUSB101: Fix mem leak in error path of kaweth_download_firmware() pch_gbe: don't use flush_scheduled_work() bnx2: Always set ETH_FLAG_TXVLAN net: clear heap allocation for ethtool_get_regs() ipv6: Always clone offlink routes. dcbnl: make get_app handling symmetric for IEEE and CEE DCBx tcp: fix bug in listening_get_next() inetpeer: Use correct AVL tree base pointer in inet_getpeer(). GRO: fix merging a paged skb after non-paged skbs ...
2011-01-26Documentation: Fix kernel parameter orderingAlan Cox
A B C D E ... Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-25bonding: update documentation - alternate configuration.Nicolas de Pesloüan
The bonding documentation used to provide configuration details and examples for initscripts and sysconfig only. This patch describe the third possible configuration: /etc/network/interfaces. Signed-off-by: Nicolas de Pesloüan <nicolas.2p.debian@free.fr> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-24Merge branch 'can/at91_can-for-net-2.6' of ↵David S. Miller
git://git.pengutronix.de/git/mkl/linux-2.6
2011-01-24can: at91_can: make can_id of mailbox 0 configurableMarc Kleine-Budde
Due to a chip bug (errata 50.2.6.3 & 50.3.5.3 in "AT91SAM9263 Preliminary 6249H-ATARM-27-Jul-09") the contents of mailbox 0 may be send under certain conditions (even if disabled or in rx mode). The workaround in the errata suggests not to use the mailbox and load it with an unused identifier. This patch implements the second part of the workaround. A sysfs entry "mb0_id" is introduced. While the interface is down it can be used to configure the can_id of mailbox 0. The default value id 0x7ff. In order to use an extended can_id add the CAN_EFF_FLAG (0x80000000U) to the can_id. Example: - standard id 0x7ff: echo 0x7ff > /sys/class/net/can0/mb0_id - extended id 0x1fffffff: echo 0x9fffffff > /sys/class/net/can0/mb0_id Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Acked-by: Wolfgang Grandegger <wg@grandegger.com> Acked-by: Kurt Van Dijck <kurt.van.dijck@eia.be> For the Documentation-part: Acked-by: Wolfram Sang <w.sang@pengutronix.de>
2011-01-22docbook: fix broken serial to tty/serial movementRandy Dunlap
Fix move of drivers/serial/ to drivers/tty/, where it broke one of the docbook files: docproc: drivers/serial/serial_core.c: No such file or directory Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-22ALSA: HDA: Add a new model "asus" for Conexant 5066/205xxDavid Henningsson
BugLink: http://bugs.launchpad.net/bugs/701271 This new model, named "asus", is identical to the "hp_laptop" model, except for the location of the internal mic, which is at pin 0x1a. It is used for Asus K52JU and Lenovo G560. Signed-off-by: David Henningsson <david.henningsson@canonical.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2011-01-21Merge branch 'media_fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6 * 'media_fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (101 commits) [media] staging/lirc: fix mem leaks and ptr err usage [media] hdpvr: reduce latency of i2c read/write w/recycled buffer [media] hdpvr: enable IR part [media] rc/mceusb: timeout should be in ns, not us [media] v4l2-device: fix 'use-after-freed' oops [media] v4l2-dev: don't memset video_device.dev [media] zoran: use video_device_alloc instead of kmalloc [media] w9966: zero device state after a detach [media] v4l: Fix a use-before-set in the control framework [media] v4l: Include linux/videodev2.h in media/v4l2-ctrls.h [media] DocBook/v4l: update V4L2 revision and update copyright years [media] DocBook/v4l: fix validation error in dev-rds.xml [media] v4l2-ctrls: queryctrl shouldn't attempt to replace V4L2_CID_PRIVATE_BASE IDs [media] v4l2-ctrls: fix missing 'read-only' check [media] pvrusb2: Provide more information about IR units to lirc_zilog and ir-kbd-i2c [media] ir-kbd-i2c: Add back defaults setting for Zilog Z8's at addr 0x71 [media] lirc_zilog: Update TODO.lirc_zilog [media] lirc_zilog: Add Andy Walls to copyright notice and authors list [media] lirc_zilog: Remove useless struct i2c_driver.command function [media] lirc_zilog: Remove unneeded tests for existence of the IR Tx function ...
2011-01-21Merge branch 'irq-cleanup-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'irq-cleanup-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (37 commits) um: Use generic irq Kconfig tile: Use generic irq Kconfig sparc: Use generic irq Kconfig score: Use generic irq Kconfig powerpc: Use generic irq Kconfig parisc: Use generic irq Kconfig mn10300: Use generic irq Kconfig microblaze: Use generic irq Kconfig m68knommu: Use generic irq Kconfig ia64: Use generic irq Kconfig frv: Use generic irq Kconfig blackfin: Use generic irq Kconfig alpha: Use generic irq Kconfig genirq: Remove __do_IRQ m32r: Convert to generic irq Kconfig m32r: Convert usrv platform irq handling m32r: Convert opsput_lcdpld irq chip m32r: Convert opsput lanpld irq chip m32r: Convert opsput pld irq chip m32r: Convert opsput irq chip ...
2011-01-21Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6: ALSA: hda - Fix EAPD to low on CZC P10T tablet computer with ALC662 ALSA: HDA: Add SKU ignore for another Thinkpad Edge 14 ALSA: hda - Fix "unused variable" compile warning ALSA: hda - Add quirk for HP Z-series workstation Revert "ALSA: HDA: Create mixers on ALC887" ASoC: PXA: Fix codec address on Zipit Z2 ASoC: PXA: Fix jack detection on Zipit Z2 ASoC: Blackfin: fix DAI/SPORT config dependency issues ASoC: Blackfin TDM: use external frame syncs ASoC: Blackfin AC97: fix build error after multi-component update ASoC: Blackfin TDM: fix missed snd_soc_dai_get_drvdata update ASoC: documentation updates ALSA: ice1712 delta - initialize SPI clock
2011-01-21genirq: Remove __do_IRQThomas Gleixner
All architectures are finally converted. Remove the cruft. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Richard Henderson <rth@twiddle.net> Cc: Mike Frysinger <vapier@gentoo.org> Cc: David Howells <dhowells@redhat.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Greg Ungerer <gerg@uclinux.org> Cc: Michal Simek <monstr@monstr.eu> Acked-by: David Howells <dhowells@redhat.com> Cc: Kyle McMartin <kyle@mcmartin.ca> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Chen Liqin <liqin.chen@sunplusct.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Jeff Dike <jdike@addtoit.com>
2011-01-21Merge branch 'fix/asoc' into for-linusTakashi Iwai
2011-01-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linusLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus: virtio: remove virtio-pci root device LGUEST_GUEST: fix unmet direct dependencies (VIRTUALIZATION && VIRTIO) lguest: compile fixes lguest: Use this_cpu_ops lguest: document --rng in example Launcher lguest: example launcher to use guard pages, drop PROT_EXEC, fix limit logic lguest: --username and --chroot options
2011-01-20lguest: document --rng in example LauncherPhilip Sanderson
Rusty Russell wrote: > Ah, it will appear as /dev/hwrng. It's a weirdness of Linux that our actual > hardware number generators are not wired up to /dev/random... Reflected this in the documentation, thanks :-) Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-01-20lguest: example launcher to use guard pages, drop PROT_EXEC, fix limit logicPhilip Sanderson
PROT_EXEC seems to be completely unnecessary (as the lguest binary never executes there), and will allow it to work with SELinux (and more importantly, PaX :-) as they can/do forbid writable and executable mappings. Also, map PROT_NONE guard pages at start and end of guest memory for extra paranoia. I changed the length check to addr + size > guest_limit because >= is wrong (addr of 0, size of getpagesize() with a guest_limit of getpagesize() would false positive). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-01-20lguest: --username and --chroot optionsPhilip Sanderson
I've attached a patch which implements dropping to privileges and chrooting to a directory. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-01-19[media] DocBook/v4l: update V4L2 revision and update copyright yearsHans Verkuil
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-01-19[media] DocBook/v4l: fix validation error in dev-rds.xmlHans Verkuil
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-01-19[media] v4l2-ctrls: v4l2_ctrl_handler_setup must set is_new to 1Hans Verkuil
Renamed has_new to is_new. Drivers can use the is_new field to determine if a new value was specified for a control. The v4l2_ctrl_handler_setup() must always set this to 1 since the setup has to force a full update of all controls. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-01-18hwmon: (lm93) Add support for LM94Guenter Roeck
This patch adds basic support for LM94 to the LM93 driver. LM94 specific sensors and features are not supported. Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com> Acked-by: Jean Delvare <khali@linux-fr.org>
2011-01-18ASoC: documentation updatesSeungwhan Youn
This patch is only for RFC purpose of ASoC documentation updates which match with current ASoC codes with documents. Mostly modify features are modified to be sync with changes after multi-component patches. Signed-off-by: Seungwhan Youn <sw.youn@samsung.com> Acked-by: Liam Girdwood <lrg@slimlogic.co.uk> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-01-17fallocate should be a file operationChristoph Hellwig
Currently all filesystems except XFS implement fallocate asynchronously, while XFS forced a commit. Both of these are suboptimal - in case of O_SYNC I/O we really want our allocation on disk, especially for the !KEEP_SIZE case where we actually grow the file with user-visible zeroes. On the other hand always commiting the transaction is a bad idea for fast-path uses of fallocate like for example in recent Samba versions. Given that block allocation is a data plane operation anyway change it from an inode operation to a file operation so that we have the file structure available that lets us check for O_SYNC. This also includes moving the code around for a few of the filesystems, and remove the already unnedded S_ISDIR checks given that we only wire up fallocate for regular files. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-16Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (23 commits) sanitize vfsmount refcounting changes fix old umount_tree() breakage autofs4: Merge the remaining dentry ops tables Unexport do_add_mount() and add in follow_automount(), not ->d_automount() Allow d_manage() to be used in RCU-walk mode Remove a further kludge from __do_follow_link() autofs4: Bump version autofs4: Add v4 pseudo direct mount support autofs4: Fix wait validation autofs4: Clean up autofs4_free_ino() autofs4: Clean up dentry operations autofs4: Clean up inode operations autofs4: Remove unused code autofs4: Add d_manage() dentry operation autofs4: Add d_automount() dentry operation Remove the automount through follow_link() kludge code from pathwalk CIFS: Use d_automount() rather than abusing follow_link() NFS: Use d_automount() rather than abusing follow_link() AFS: Use d_automount() rather than abusing follow_link() Add an AT_NO_AUTOMOUNT flag to suppress terminal automount ...
2011-01-15Unexport do_add_mount() and add in follow_automount(), not ->d_automount()David Howells
Unexport do_add_mount() and make ->d_automount() return the vfsmount to be added rather than calling do_add_mount() itself. follow_automount() will then do the addition. This slightly complicates things as ->d_automount() normally wants to add the new vfsmount to an expiration list and start an expiration timer. The problem with that is that the vfsmount will be deleted if it has a refcount of 1 and the timer will not repeat if the expiration list is empty. To this end, we require the vfsmount to be returned from d_automount() with a refcount of (at least) 2. One of these refs will be dropped unconditionally. In addition, follow_automount() must get a 3rd ref around the call to do_add_mount() lest it eat a ref and return an error, leaving the mount we have open to being expired as we would otherwise have only 1 ref on it. d_automount() should also add the the vfsmount to the expiration list (by calling mnt_set_expiry()) and start the expiration timer before returning, if this mechanism is to be used. The vfsmount will be unlinked from the expiration list by follow_automount() if do_add_mount() fails. This patch also fixes the call to do_add_mount() for AFS to propagate the mount flags from the parent vfsmount. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-15Allow d_manage() to be used in RCU-walk modeDavid Howells
Allow d_manage() to be called from pathwalk when it is in RCU-walk mode as well as when it is in Ref-walk mode. This permits __follow_mount_rcu() to call d_manage() directly. d_manage() needs a parameter to indicate that it is in RCU-walk mode as it isn't allowed to sleep if in that mode (but should return -ECHILD instead). autofs4_d_manage() can then be set to retain RCU-walk mode if the daemon accesses it and otherwise request dropping back to ref-walk mode. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-15Add a dentry op to allow processes to be held during pathwalk transitDavid Howells
Add a dentry op (d_manage) to permit a filesystem to hold a process and make it sleep when it tries to transit away from one of that filesystem's directories during a pathwalk. The operation is keyed off a new dentry flag (DCACHE_MANAGE_TRANSIT). The filesystem is allowed to be selective about which processes it holds and which it permits to continue on or prohibits from transiting from each flagged directory. This will allow autofs to hold up client processes whilst letting its userspace daemon through to maintain the directory or the stuff behind it or mounted upon it. The ->d_manage() dentry operation: int (*d_manage)(struct path *path, bool mounting_here); takes a pointer to the directory about to be transited away from and a flag indicating whether the transit is undertaken by do_add_mount() or do_move_mount() skipping through a pile of filesystems mounted on a mountpoint. It should return 0 if successful and to let the process continue on its way; -EISDIR to prohibit the caller from skipping to overmounted filesystems or automounting, and to use this directory; or some other error code to return to the user. ->d_manage() is called with namespace_sem writelocked if mounting_here is true and no other locks held, so it may sleep. However, if mounting_here is true, it may not initiate or wait for a mount or unmount upon the parameter directory, even if the act is actually performed by userspace. Within fs/namei.c, follow_managed() is extended to check with d_manage() first on each managed directory, before transiting away from it or attempting to automount upon it. follow_down() is renamed follow_down_one() and should only be used where the filesystem deliberately intends to avoid management steps (e.g. autofs). A new follow_down() is added that incorporates the loop done by all other callers of follow_down() (do_add/move_mount(), autofs and NFSD; whilst AFS, NFS and CIFS do use it, their use is removed by converting them to use d_automount()). The new follow_down() calls d_manage() as appropriate. It also takes an extra parameter to indicate if it is being called from mount code (with namespace_sem writelocked) which it passes to d_manage(). follow_down() ignores automount points so that it can be used to mount on them. __follow_mount_rcu() is made to abort rcu-walk mode if it hits a directory with DCACHE_MANAGE_TRANSIT set on the basis that we're probably going to have to sleep. It would be possible to enter d_manage() in rcu-walk mode too, and have that determine whether to abort or not itself. That would allow the autofs daemon to continue on in rcu-walk mode. Note that DCACHE_MANAGE_TRANSIT on a directory should be cleared when it isn't required as every tranist from that directory will cause d_manage() to be invoked. It can always be set again when necessary. ========================== WHAT THIS MEANS FOR AUTOFS ========================== Autofs currently uses the lookup() inode op and the d_revalidate() dentry op to trigger the automounting of indirect mounts, and both of these can be called with i_mutex held. autofs knows that the i_mutex will be held by the caller in lookup(), and so can drop it before invoking the daemon - but this isn't so for d_revalidate(), since the lock is only held on _some_ of the code paths that call it. This means that autofs can't risk dropping i_mutex from its d_revalidate() function before it calls the daemon. The bug could manifest itself as, for example, a process that's trying to validate an automount dentry that gets made to wait because that dentry is expired and needs cleaning up: mkdir S ffffffff8014e05a 0 32580 24956 Call Trace: [<ffffffff885371fd>] :autofs4:autofs4_wait+0x674/0x897 [<ffffffff80127f7d>] avc_has_perm+0x46/0x58 [<ffffffff8009fdcf>] autoremove_wake_function+0x0/0x2e [<ffffffff88537be6>] :autofs4:autofs4_expire_wait+0x41/0x6b [<ffffffff88535cfc>] :autofs4:autofs4_revalidate+0x91/0x149 [<ffffffff80036d96>] __lookup_hash+0xa0/0x12f [<ffffffff80057a2f>] lookup_create+0x46/0x80 [<ffffffff800e6e31>] sys_mkdirat+0x56/0xe4 versus the automount daemon which wants to remove that dentry, but can't because the normal process is holding the i_mutex lock: automount D ffffffff8014e05a 0 32581 1 32561 Call Trace: [<ffffffff80063c3f>] __mutex_lock_slowpath+0x60/0x9b [<ffffffff8000ccf1>] do_path_lookup+0x2ca/0x2f1 [<ffffffff80063c89>] .text.lock.mutex+0xf/0x14 [<ffffffff800e6d55>] do_rmdir+0x77/0xde [<ffffffff8005d229>] tracesys+0x71/0xe0 [<ffffffff8005d28d>] tracesys+0xd5/0xe0 which means that the system is deadlocked. This patch allows autofs to hold up normal processes whilst the daemon goes ahead and does things to the dentry tree behind the automouter point without risking a deadlock as almost no locks are held in d_manage() and none in d_automount(). Signed-off-by: David Howells <dhowells@redhat.com> Was-Acked-by: Ian Kent <raven@themaw.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-15Add a dentry op to handle automounting rather than abusing follow_link()David Howells
Add a dentry op (d_automount) to handle automounting directories rather than abusing the follow_link() inode operation. The operation is keyed off a new dentry flag (DCACHE_NEED_AUTOMOUNT). This also makes it easier to add an AT_ flag to suppress terminal segment automount during pathwalk and removes the need for the kludge code in the pathwalk algorithm to handle directories with follow_link() semantics. The ->d_automount() dentry operation: struct vfsmount *(*d_automount)(struct path *mountpoint); takes a pointer to the directory to be mounted upon, which is expected to provide sufficient data to determine what should be mounted. If successful, it should return the vfsmount struct it creates (which it should also have added to the namespace using do_add_mount() or similar). If there's a collision with another automount attempt, NULL should be returned. If the directory specified by the parameter should be used directly rather than being mounted upon, -EISDIR should be returned. In any other case, an error code should be returned. The ->d_automount() operation is called with no locks held and may sleep. At this point the pathwalk algorithm will be in ref-walk mode. Within fs/namei.c itself, a new pathwalk subroutine (follow_automount()) is added to handle mountpoints. It will return -EREMOTE if the automount flag was set, but no d_automount() op was supplied, -ELOOP if we've encountered too many symlinks or mountpoints, -EISDIR if the walk point should be used without mounting and 0 if successful. The path will be updated to point to the mounted filesystem if a successful automount took place. __follow_mount() is replaced by follow_managed() which is more generic (especially with the patch that adds ->d_manage()). This handles transits from directories during pathwalk, including automounting and skipping over mountpoints (and holding processes with the next patch). __follow_mount_rcu() will jump out of RCU-walk mode if it encounters an automount point with nothing mounted on it. follow_dotdot*() does not handle automounts as you don't want to trigger them whilst following "..". I've also extracted the mount/don't-mount logic from autofs4 and included it here. It makes the mount go ahead anyway if someone calls open() or creat(), tries to traverse the directory, tries to chdir/chroot/etc. into the directory, or sticks a '/' on the end of the pathname. If they do a stat(), however, they'll only trigger the automount if they didn't also say O_NOFOLLOW. I've also added an inode flag (S_AUTOMOUNT) so that filesystems can mark their inodes as automount points. This flag is automatically propagated to the dentry as DCACHE_NEED_AUTOMOUNT by __d_instantiate(). This saves NFS and could save AFS a private flag bit apiece, but is not strictly necessary. It would be preferable to do the propagation in d_set_d_op(), but that doesn't normally have access to the inode. [AV: fixed breakage in case if __follow_mount_rcu() fails and nameidata_drop_rcu() succeeds in RCU case of do_lookup(); we need to fall through to non-RCU case after that, rather than just returning with ungrabbed *path] Signed-off-by: David Howells <dhowells@redhat.com> Was-Acked-by: Ian Kent <raven@themaw.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-post-merge-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-post-merge-2.6: [SCSI] target: Add LIO target core v4.0.0-rc6 [SCSI] sd,sr: kill compat SDEV_MEDIA_CHANGE event [SCSI] sd: implement sd_check_events()
2011-01-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (47 commits) GRETH: resolve SMP issues and other problems GRETH: handle frame error interrupts GRETH: avoid writing bad speed/duplex when setting transfer mode GRETH: fixed skb buffer memory leak on frame errors GRETH: GBit transmit descriptor handling optimization GRETH: fix opening/closing GRETH: added raw AMBA vendor/device number to match against. cassini: Fix build bustage on x86. e1000e: consistent use of Rx/Tx vs. RX/TX/rx/tx in comments/logs e1000e: update Copyright for 2011 e1000: Avoid unhandled IRQ r8169: keep firmware in memory. netdev: tilepro: Use is_unicast_ether_addr helper etherdevice.h: Add is_unicast_ether_addr function ks8695net: Use default implementation of ethtool_ops::get_link ks8695net: Disable non-working ethtool operations USB CDC NCM: Don't deref NULL in cdc_ncm_rx_fixup() and don't use uninitialized variable. vxge: Remember to release firmware after upgrading firmware netdev: bfin_mac: Remove is_multicast_ether_addr use in netdev_for_each_mc_addr ipsec: update MAX_AH_AUTH_LEN to support sha512 ...
2011-01-14Merge branch 'for-2.6.38' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
* 'for-2.6.38' of git://linux-nfs.org/~bfields/linux: (62 commits) nfsd4: fix callback restarting nfsd: break lease on unlink, link, and rename nfsd4: break lease on nfsd setattr nfsd: don't support msnfs export option nfsd4: initialize cb_per_client nfsd4: allow restarting callbacks nfsd4: simplify nfsd4_cb_prepare nfsd4: give out delegations more quickly in 4.1 case nfsd4: add helper function to run callbacks nfsd4: make sure sequence flags are set after destroy_session nfsd4: re-probe callback on connection loss nfsd4: set sequence flag when backchannel is down nfsd4: keep finer-grained callback status rpc: allow xprt_class->setup to return a preexisting xprt rpc: keep backchannel xprt as long as server connection rpc: move sk_bc_xprt to svc_xprt nfsd4: allow backchannel recovery nfsd4: support BIND_CONN_TO_SESSION nfsd4: modify session list under cl_lock Documentation: fl_mylease no longer exists ... Fix up conflicts in fs/nfsd/vfs.c with the vfs-scale work. The vfs-scale work touched some msnfs cases, and this merge removes support for that entirely, so the conflict was trivial to resolve.
2011-01-14[SCSI] target: Add LIO target core v4.0.0-rc6Nicholas Bellinger
LIO target is a full featured in-kernel target framework with the following feature set: High-performance, non-blocking, multithreaded architecture with SIMD support. Advanced SCSI feature set: * Persistent Reservations (PRs) * Asymmetric Logical Unit Assignment (ALUA) * Protocol and intra-nexus multiplexing, load-balancing and failover (MC/S) * Full Error Recovery (ERL=0,1,2) * Active/active task migration and session continuation (ERL=2) * Thin LUN provisioning (UNMAP and WRITE_SAMExx) Multiprotocol target plugins Storage media independence: * Virtualization of all storage media; transparent mapping of IO to LUNs * No hard limits on number of LUNs per Target; maximum LUN size ~750 TB * Backstores: SATA, SAS, SCSI, BluRay, DVD, FLASH, USB, ramdisk, etc. Standards compliance: * Full compliance with IETF (RFC 3720) * Full implementation of SPC-4 PRs and ALUA Significant code cleanups done by Christoph Hellwig. [jejb: fix up for new block bdev exclusive interface. Minor fixes from Randy Dunlap and Dan Carpenter.] Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-01-14revert documentaion update for memcg's dirty ratio.KAMEZAWA Hiroyuki
Subjct: Revert memory cgroup dirty_ratio Documentation. The commit ece72400c2a27a3d726cb0854449f991d9fcd2da adds documentation for memcg's dirty ratio. But the function is not implemented yet. Remove the documentation for avoiding confusing users. Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Reviewed-by: Greg Thelen <gthelen@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13Merge branch 'release' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (59 commits) ACPI / PM: Fix build problems for !CONFIG_ACPI related to NVS rework ACPI: fix resource check message ACPI / Battery: Update information on info notification and resume ACPI: Drop device flag wake_capable ACPI: Always check if _PRW is present before trying to evaluate it ACPI / PM: Check status of power resources under mutexes ACPI / PM: Rename acpi_power_off_device() ACPI / PM: Drop acpi_power_nocheck ACPI / PM: Drop acpi_bus_get_power() Platform / x86: Make fujitsu_laptop use acpi_bus_update_power() ACPI / Fan: Rework the handling of power resources ACPI / PM: Register power resource devices as soon as they are needed ACPI / PM: Register acpi_power_driver early ACPI / PM: Add function for updating device power state consistently ACPI / PM: Add function for device power state initialization ACPI / PM: Introduce __acpi_bus_get_power() ACPI / PM: Introduce function for refcounting device power resources ACPI / PM: Add functions for manipulating lists of power resources ACPI / PM: Prevent acpi_power_get_inferred_state() from making changes ACPICA: Update version to 20101209 ...
2011-01-13Merge branch 'vfs-scale-working' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin * 'vfs-scale-working' of git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin: fs: fix do_last error case when need_reval_dot nfs: add missing rcu-walk check fs: hlist UP debug fixup fs: fix dropping of rcu-walk from force_reval_path fs: force_reval_path drop rcu-walk before d_invalidate fs: small rcu-walk documentation fixes Fixed up trivial conflicts in Documentation/filesystems/porting