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2011-01-07fs: rcu-walk for path lookupNick Piggin
Perform common cases of path lookups without any stores or locking in the ancestor dentry elements. This is called rcu-walk, as opposed to the current algorithm which is a refcount based walk, or ref-walk. This results in far fewer atomic operations on every path element, significantly improving path lookup performance. It also avoids cacheline bouncing on common dentries, significantly improving scalability. The overall design is like this: * LOOKUP_RCU is set in nd->flags, which distinguishes rcu-walk from ref-walk. * Take the RCU lock for the entire path walk, starting with the acquiring of the starting path (eg. root/cwd/fd-path). So now dentry refcounts are not required for dentry persistence. * synchronize_rcu is called when unregistering a filesystem, so we can access d_ops and i_ops during rcu-walk. * Similarly take the vfsmount lock for the entire path walk. So now mnt refcounts are not required for persistence. Also we are free to perform mount lookups, and to assume dentry mount points and mount roots are stable up and down the path. * Have a per-dentry seqlock to protect the dentry name, parent, and inode, so we can load this tuple atomically, and also check whether any of its members have changed. * Dentry lookups (based on parent, candidate string tuple) recheck the parent sequence after the child is found in case anything changed in the parent during the path walk. * inode is also RCU protected so we can load d_inode and use the inode for limited things. * i_mode, i_uid, i_gid can be tested for exec permissions during path walk. * i_op can be loaded. When we reach the destination dentry, we lock it, recheck lookup sequence, and increment its refcount and mountpoint refcount. RCU and vfsmount locks are dropped. This is termed "dropping rcu-walk". If the dentry refcount does not match, we can not drop rcu-walk gracefully at the current point in the lokup, so instead return -ECHILD (for want of a better errno). This signals the path walking code to re-do the entire lookup with a ref-walk. Aside from the final dentry, there are other situations that may be encounted where we cannot continue rcu-walk. In that case, we drop rcu-walk (ie. take a reference on the last good dentry) and continue with a ref-walk. Again, if we can drop rcu-walk gracefully, we return -ECHILD and do the whole lookup using ref-walk. But it is very important that we can continue with ref-walk for most cases, particularly to avoid the overhead of double lookups, and to gain the scalability advantages on common path elements (like cwd and root). The cases where rcu-walk cannot continue are: * NULL dentry (ie. any uncached path element) * parent with d_inode->i_op->permission or ACLs * dentries with d_revalidate * Following links In future patches, permission checks and d_revalidate become rcu-walk aware. It may be possible eventually to make following links rcu-walk aware. Uncached path elements will always require dropping to ref-walk mode, at the very least because i_mutex needs to be grabbed, and objects allocated. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07fs: icache RCU free inodesNick Piggin
RCU free the struct inode. This will allow: - Subsequent store-free path walking patch. The inode must be consulted for permissions when walking, so an RCU inode reference is a must. - sb_inode_list_lock to be moved inside i_lock because sb list walkers who want to take i_lock no longer need to take sb_inode_list_lock to walk the list in the first place. This will simplify and optimize locking. - Could remove some nested trylock loops in dcache code - Could potentially simplify things a bit in VM land. Do not need to take the page lock to follow page->mapping. The downsides of this is the performance cost of using RCU. In a simple creat/unlink microbenchmark, performance drops by about 10% due to inability to reuse cache-hot slab objects. As iterations increase and RCU freeing starts kicking over, this increases to about 20%. In cases where inode lifetimes are longer (ie. many inodes may be allocated during the average life span of a single inode), a lot of this cache reuse is not applicable, so the regression caused by this patch is smaller. The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU, however this adds some complexity to list walking and store-free path walking, so I prefer to implement this at a later date, if it is shown to be a win in real situations. I haven't found a regression in any non-micro benchmark so I doubt it will be a problem. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07fs: dcache remove dcache_lockNick Piggin
dcache_lock no longer protects anything. remove it. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07fs: change d_hash for rcu-walkNick Piggin
Change d_hash so it may be called from lock-free RCU lookups. See similar patch for d_compare for details. For in-tree filesystems, this is just a mechanical change. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07fs: change d_compare for rcu-walkNick Piggin
Change d_compare so it may be called from lock-free RCU lookups. This does put significant restrictions on what may be done from the callback, however there don't seem to have been any problems with in-tree fses. If some strange use case pops up that _really_ cannot cope with the rcu-walk rules, we can just add new rcu-unaware callbacks, which would cause name lookup to drop out of rcu-walk mode. For in-tree filesystems, this is just a mechanical change. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07fs: change d_delete semanticsNick Piggin
Change d_delete from a dentry deletion notification to a dentry caching advise, more like ->drop_inode. Require it to be constant and idempotent, and not take d_lock. This is how all existing filesystems use the callback anyway. This makes fine grained dentry locking of dput and dentry lru scanning much simpler. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-04remove trim_fs method from Documentation/filesystems/LockingChristoph Hellwig
The ->trim_fs has been removed meanwhile, so remove it from the documentation as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-03watchdog: Improve initialisation error message and documentationBen Hutchings
The error message 'NMI watchdog failed to create perf event...' does not make it clear that this is a fatal error for the watchdog. It also currently prints the error value as a pointer, rather than extracting the error code with PTR_ERR(). Fix that. Add a note to the description of the 'nowatchdog' kernel parameter to associate it with this message. Reported-by: Cesare Leonardi <celeonar@gmail.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: 599368@bugs.debian.org Cc: 608138@bugs.debian.org Cc: Don Zickus <dzickus@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: <stable@kernel.org> # .37.x and later LKML-Reference: <1294009362.3167.126.camel@localhost> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-12-30update Documentation/filesystems/LockingChristoph Hellwig
Mostly inspired by all the recent BKL removal changes, but a lot of older updates also weren't properly recorded. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-12-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6: [SCSI] fix up documentation for change in ->queuecommand to lockless calling [SCSI] bfa: rename log_level to bfa_log_level
2010-12-22taskstats: pad taskstats netlink response for aligment issues on ia64Jeff Mahoney
The taskstats structure is internally aligned on 8 byte boundaries but the layout of the aggregrate reply, with two NLA headers and the pid (each 4 bytes), actually force the entire structure to be unaligned. This causes the kernel to issue unaligned access warnings on some architectures like ia64. Unfortunately, some software out there doesn't properly unroll the NLA packet and assumes that the start of the taskstats structure will always be 20 bytes from the start of the netlink payload. Aligning the start of the taskstats structure breaks this software, which we don't want. So, for now the alignment only happens on architectures that require it and those users will have to update to fixed versions of those packages. Space is reserved in the packet only when needed. This ifdef should be removed in several years e.g. 2012 once we can be confident that fixed versions are installed on most systems. We add the padding before the aggregate since the aggregate is already a defined type. Commit 85893120 ("delayacct: align to 8 byte boundary on 64-bit systems") previously addressed the alignment issues by padding out the pid field. This was supposed to be a compatible change but the circumstances described above mean that it wasn't. This patch backs out that change, since it was a hack, and introduces a new NULL attribute type to provide the padding. Padding the response with 4 bytes avoids allocating an aligned taskstats structure and copying it back. Since the structure weighs in at 328 bytes, it's too big to do it on the stack. Signed-off-by: Jeff Mahoney <jeffm@suse.com> Reported-by: Brian Rogers <brian@xyzw.org> Cc: Jeff Mahoney <jeffm@suse.com> Cc: Guillaume Chazarain <guichaz@gmail.com> Cc: Balbir Singh <balbir@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-12-22mm: vmscan: tracepoint: account for scanned pages similarly for both ftrace ↵Mel Gorman
and vmstat When correlating ftrace results with /proc/vmstat, I noticed that the reporting scripts value for "pages scanned" differed significantly. Both values were "right" depending on how you look at it. The difference is due to vmstat only counting scanning of the inactive list towards pages scanned. The analysis script for the tracepoint counts active and inactive list yielding a far higher value than vmstat. The resulting scanning/reclaim ratio looks much worse. The tracepoint is ok but this patch updates the reporting script so that the report values for scanned are similar to vmstat. Signed-off-by: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-12-21[SCSI] fix up documentation for change in ->queuecommand to lockless callingJames Bottomley
The current doc still says we call it with the host lock held, which is going to cause confusion. Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-12-18Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: x86: avoid high BIOS area when allocating address space x86: avoid E820 regions when allocating address space x86: avoid low BIOS area when allocating address space resources: add arch hook for preventing allocation in reserved areas Revert "resources: support allocating space within a region from the top down" Revert "PCI: allocate bus resources from the top down" Revert "x86/PCI: allocate space from the end of a region, not the beginning" Revert "x86: allocate space within a region top-down" Revert "PCI: fix pci_bus_alloc_resource() hang, prefer positive decode" PCI: Update MCP55 quirk to not affect non HyperTransport variants
2010-12-17Revert "resources: support allocating space within a region from the top down"Bjorn Helgaas
This reverts commit e7f8567db9a7f6b3151b0b275e245c1cef0d9c70. Acked-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-12-16PM / Runtime: Fix pm_runtime_suspended()Rafael J. Wysocki
There are some situations (e.g. in __pm_generic_call()), where pm_runtime_suspended() is used to decide whether or not to execute a device's (system) ->suspend() callback. The callback is not executed if pm_runtime_suspended() returns true, but it does so for devices that don't even support runtime PM, because the power.disable_depth device field is ignored by it. This leads to problems (i.e. devices are not suspened when they should), so rework pm_runtime_suspended() so that it returns false if the device's power.disable_depth field is different from zero. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Cc: stable@kernel.org
2010-12-14Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6Linus Torvalds
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: NFS: Fix panic after nfs_umount() nfs: remove extraneous and problematic calls to nfs_clear_request nfs: kernel should return EPROTONOSUPPORT when not support NFSv4 NFS: Fix fcntl F_GETLK not reporting some conflicts nfs: Discard ACL cache on mode update NFS: Readdir cleanups NFS: nfs_readdir_search_for_cookie() don't mark as eof if cookie not found NFS: Fix a memory leak in nfs_readdir Call the filesystem back whenever a page is removed from the page cache NFS: Ensure we use the correct cookie in nfs_readdir_xdr_filler
2010-12-07Merge branch 'for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mjg59/platform-drivers-x86 * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mjg59/platform-drivers-x86: wmi: use memcmp instead of strncmp to compare GUIDs ACPI, hp-wmi: Fix memory leak in acpi query msi-wmi: fix semantically incorrect use of keycode instead of scancode msi-wmi: Add mute key support asus-laptop: add wimax and wwan support eeepc-wmi: fix compiler warning ibm_rtl: _RTL_ is not available in UEFI mode ibm_rtl: Loosen the DMI criteria to all IBM machines drivers/platform/x86/thinkpad_acpi.c: delete double assignment eeepc-wmi: add cpufv sysfs documentation toshiba_acpi.c: Add key_entry for a lone FN keypress ibm_rtl: fix printk format warning
2010-12-02Documentation/filesystems/vfs.txt: fix ->repeasepage() descriptionAndrew Morton
->releasepage() does not remove the page from the mapping. Acked-by: Neil Brown <neilb@suse.de> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-12-02Merge branch 'driver-core-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6 * 'driver-core-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: uio: Change mail address of Hans J. Koch driver core: prune docs about device_interface driver core: the development tree has switched to git
2010-12-02Merge branch 'rbd-sysfs' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client * 'rbd-sysfs' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: rbd: replace the rbd sysfs interface
2010-12-02Call the filesystem back whenever a page is removed from the page cacheLinus Torvalds
NFS needs to be able to release objects that are stored in the page cache once the page itself is no longer visible from the page cache. This patch adds a callback to the address space operations that allows filesystems to perform page cleanups once the page has been removed from the page cache. Original patch by: Linus Torvalds <torvalds@linux-foundation.org> [trondmy: cover the cases of invalidate_inode_pages2() and truncate_inode_pages()] Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-12-01rbd: replace the rbd sysfs interfaceYehuda Sadeh
The new interface creates directories per mapped image and under each it creates a subdir per available snapshot. This allows keeping a cleaner interface within the sysfs guidelines. The ABI documentation was updated too. Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net> Signed-off-by: Sage Weil <sage@newdream.net>
2010-11-29Merge 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: (27 commits) af_unix: limit recursion level pch_gbe driver: The wrong of initializer entry pch_gbe dreiver: chang author ucc_geth: fix ucc halt problem in half duplex mode inet: Fix __inet_inherit_port() to correctly increment bsockets and num_owners ehea: Add some info messages and fix an issue hso: fix disable_net NET: wan/x25_asy, move lapb_unregister to x25_asy_close_tty cxgb4vf: fix setting unicast/multicast addresses ... net, ppp: Report correct error code if unit allocation failed DECnet: don't leak uninitialized stack byte au1000_eth: fix invalid address accessing the MAC enable register dccp: fix error in updating the GAR tcp: restrict net.ipv4.tcp_adv_win_scale (#20312) netns: Don't leak others' openreq-s in proc Net: ceph: Makefile: Remove unnessary code vhost/net: fix rcu check usage econet: fix CVE-2010-3848 econet: fix CVE-2010-3850 econet: disallow NULL remote addr for sendmsg(), fixes CVE-2010-3849 ...
2010-11-29Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bpLinus Torvalds
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp: EDAC: Fix typos in Documentation/edac.txt EDAC, MCE: Fix edac_init_mce_inject error handling EDAC: Remove deprecated kbuild goal definitions
2010-11-28tcp: restrict net.ipv4.tcp_adv_win_scale (#20312)Alexey Dobriyan
tcp_win_from_space() does the following: if (sysctl_tcp_adv_win_scale <= 0) return space >> (-sysctl_tcp_adv_win_scale); else return space - (space >> sysctl_tcp_adv_win_scale); "space" is int. As per C99 6.5.7 (3) shifting int for 32 or more bits is undefined behaviour. Indeed, if sysctl_tcp_adv_win_scale is exactly 32, space >> 32 equals space and function returns 0. Which means we busyloop in tcp_fixup_rcvbuf(). Restrict net.ipv4.tcp_adv_win_scale to [-31, 31]. Fix https://bugzilla.kernel.org/show_bug.cgi?id=20312 Steps to reproduce: echo 32 >/proc/sys/net/ipv4/tcp_adv_win_scale wget www.kernel.org [softlockup] Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-25EDAC: Fix typos in Documentation/edac.txtRaoul Bhatia
Fix trivial typos in edac.txt Signed-off-by: Raoul Bhatia <r.bhatia@ipax.at> Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
2010-11-25Merge branch 'fbdev-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lethal/fbdev-2.6 * 'fbdev-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/fbdev-2.6: sisfb: delete osdef.h sisfb: move the CONFIG warning to sis_main.c sisfb: replace SiS_SetMemory with memset_io sisfb: remove InPort/OutPort wrappers sisfb: use CONFIG_FB_SIS_301/315 instead of SIS301/315H sisfb: delete redudant #define SIS_LINUX_KERNEL sisfb: delete dead SIS_XORG_XF86 code sisfb: delete fallback code for pci_map_rom() sisfb: delete obsolete PCI ROM bug workaround fbdev: Update documentation index file. lxfb: Program panel v/h sync output polarity correctly fbcmap: integer overflow bug fbcmap: cleanup white space in fb_alloc_cmap() MAINTAINERS: Add fbdev patchwork entry, tidy up file patterns. fbdev: da8xx: punt duplicated FBIO_WAITFORVSYNC define fbdev: sh_mobile_lcdcfb: fix bug in reconfig()
2010-11-25Merge branch 'sh-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6 * 'sh-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: sh: clkfwk: Build fix for non-legacy CPG changes. sh: Use GCC __builtin_prefetch() to implement prefetch(). sh: fix vsyscall compilation due to .eh_frame issue sh: avoid to flush all cache in sys_cacheflush sh: clkfwk: Disable init clk op for non-legacy clocks. sh: clkfwk: Kill off now unused algo_id in set_rate op. sh: clkfwk: Kill off unused clk_set_rate_ex().
2010-11-25cgroups: make swap accounting default behavior configurableMichal Hocko
Swap accounting can be configured by CONFIG_CGROUP_MEM_RES_CTLR_SWAP configuration option and then it is turned on by default. There is a boot option (noswapaccount) which can disable this feature. This makes it hard for distributors to enable the configuration option as this feature leads to a bigger memory consumption and this is a no-go for general purpose distribution kernel. On the other hand swap accounting may be very usuful for some workloads. This patch adds a new configuration option which controls the default behavior (CGROUP_MEM_RES_CTLR_SWAP_ENABLED). If the option is selected then the feature is turned on by default. It also adds a new boot parameter swapaccount[=1|0] which enhances the original noswapaccount parameter semantic by means of enable/disable logic (defaults to 1 if no value is provided to be still consistent with noswapaccount). The default behavior is unchanged (if CONFIG_CGROUP_MEM_RES_CTLR_SWAP is enabled then CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED is enabled as well) Signed-off-by: Michal Hocko <mhocko@suse.cz> Acked-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Cc: Balbir Singh <balbir@linux.vnet.ibm.com> Cc: 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>
2010-11-24asus-laptop: add wimax and wwan supportCorentin Chary
Asus UL30A has a 3G chip, but the radio is disabled by default. The DSDT also reference a WIMAX device, which is not present on this model. This patch adds two new files: wwan and wimax to control WWAN and WIMAX devices. It does not use rfkill, because like WLED and BLED, we don't know yet that the two ACPI functions will always control the radio, they may control only the leds on some hardware. We may add rfkill switchs later. Signed-off-by: Corentin Chary <corentincj@iksaif.net> Signed-off-by: Matthew Garrett <mjg@redhat.com>
2010-11-24eeepc-wmi: add cpufv sysfs documentationChris Bagwell
Based on cpufv text from sysfs-platform-eeepc-laptop that has almost same behavior. Signed-off-by: Chris Bagwell <chris@cnpbagwell.com> Signed-off-by: Matthew Garrett <mjg@redhat.com> Acked-by: Corentin Chary <corentincj@iksaif.net>
2010-11-18Documentation/development-process: more staging infoAndres Salomon
Document things that I would've liked to have known when submitting a driver to gregkh for staging. Signed-off-by: Andres Salomon <dilinger@queued.net> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-18Documentation/development-process: use -next trees instead of stagingAndres Salomon
This is confusing, as we have "staging" trees for drivers/staging. Call them -next trees. Signed-off-by: Andres Salomon <dilinger@queued.net> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-18Documentation: change email address for Hans KochHans J. Koch
My old mail address doesn't exist anymore. This changes all occurrences to my new address. Signed-off-by: Hans J. Koch <hjk@hansjkoch.de> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-18Documentation/gpio.txt: explain poll/select usageBernhard Walle
Add a bit more information how to use poll(2) on GPIO value files correctly. For me it was not clear that I need to poll(2) for POLLPRI|POLLERR or select(2) for exceptfds. Signed-off-by: Bernhard Walle <walle@corscience.de> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-18Documentation: make configfs example code simpler, clearerDan Carpenter
If "p" is NULL then it will cause an oops when we pass it to simple_strtoul(). In this case "p" can not be NULL so I removed the check. I also changed the check a little to make it more explicit that we are testing whether p points to the NUL char. Signed-off-by: Dan Carpenter <error27@gmail.com> Acked-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-18fbdev: Update documentation index file.Vicente Jimenez Aguilar
This is a simple update of the file Documentation/fb/00-INDEX based on the directory content. Signed-off-by: Vicente Jimenez Aguilar <googuy@gmail.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2010-11-16Merge branch 'pm-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6 * 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6: PM / PM QoS: Fix reversed min and max PM / OPP: Hide OPP configuration when SoCs do not provide an implementation PM: Allow devices to be removed during late suspend and early resume
2010-11-16Merge branch 'common/clkfwk' into sh-fixes-for-linusPaul Mundt
2010-11-15Merge branch 'i2c-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging * 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging: i2c: Sanity checks on adapter registration i2c: Mark i2c_adapter.id as deprecated i2c: Drivers shouldn't include <linux/i2c-id.h> i2c: Delete unused adapter IDs i2c: Remove obsolete cleanup for clientdata
2010-11-15i2c: Mark i2c_adapter.id as deprecatedJean Delvare
It's about time to make it clear that i2c_adapter.id is deprecated. Hopefully this will remind the last user to move over to a different strategy. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Jarod Wilson <jarod@redhat.com> Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com> Acked-by: Hans Verkuil <hverkuil@xs4all.nl>
2010-11-15Merge branch 'fbdev-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lethal/fbdev-2.6 * 'fbdev-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/fbdev-2.6: fsl-diu-fb: drop dead ioctl define MAINTAINERS: Add an fbdev git tree entry. OMAP: DSS: Fix documentation regarding 'vram' kernel parameter OMAP: VRAM: Fix boot-time memory allocation OMAP: VRAM: improve VRAM error prints sisfb: limit POST memory test according to PCI resource length fbdev: sh_mobile_lcdc: use correct number of modes, when using the default fbdev: sh_mobile_lcdc: use the standard CEA-861 720p timing fbdev: sh_mobile_hdmi: properly clean up modedb on monitor unplug
2010-11-15sh: clkfwk: Kill off unused clk_set_rate_ex().Paul Mundt
With the refactoring of the SH7722 clock framework some time ago this abstraction has become unecessary. Kill it off before anyone else gets the bright idea to start using it. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2010-11-12Merge 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: (66 commits) can-bcm: fix minor heap overflow gianfar: Do not call device_set_wakeup_enable() under a spinlock ipv6: Warn users if maximum number of routes is reached. docs: Add neigh/gc_thresh3 and route/max_size documentation. axnet_cs: fix resume problem for some Ax88790 chip ipv6: addrconf: don't remove address state on ifdown if the address is being kept tcp: Don't change unlocked socket state in tcp_v4_err(). x25: Prevent crashing when parsing bad X.25 facilities cxgb4vf: add call to Firmware to reset VF State. cxgb4vf: Fail open if link_start() fails. cxgb4vf: flesh out PCI Device ID Table ... cxgb4vf: fix some errors in Gather List to skb conversion cxgb4vf: fix bug in Generic Receive Offload cxgb4vf: don't implement trivial (and incorrect) ndo_select_queue() ixgbe: Look inside vlan when determining offload protocol. bnx2x: Look inside vlan when determining checksum proto. vlan: Add function to retrieve EtherType from vlan packets. virtio-net: init link state correctly ucc_geth: Fix deadlock ucc_geth: Do not bring the whole IF down when TX failure. ...
2010-11-12docs: Add neigh/gc_thresh3 and route/max_size documentation.Ben Greear
Signed-off-by: Ben Greear <greearb@candelatech.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-12Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: (27 commits) block: remove unused copy_io_context() Documentation: remove anticipatory scheduler info block: remove REQ_HARDBARRIER ioprio: rcu_read_lock/unlock protect find_task_by_vpid call (V2) ioprio: fix RCU locking around task dereference block: ioctl: fix information leak to userland block: read i_size with i_size_read() cciss: fix proc warning on attempt to remove non-existant directory bio: take care not overflow page count when mapping/copying user data block: limit vec count in bio_kmalloc() and bio_alloc_map_data() block: take care not to overflow when calculating total iov length block: check for proper length of iov entries in blk_rq_map_user_iov() cciss: remove controllers supported by hpsa cciss: use usleep_range not msleep for small sleeps cciss: limit commands allocated on reset_devices cciss: Use kernel provided PCI state save and restore functions cciss: fix board status waiting code drbd: Removed checks for REQ_HARDBARRIER on incomming BIOs drbd: REQ_HARDBARRIER -> REQ_FUA transition for meta data accesses drbd: Removed the BIO_RW_BARRIER support form the receiver/epoch code ...
2010-11-12Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfsLinus Torvalds
* 'for-linus' of git://oss.sgi.com/xfs/xfs: xfs: remove incorrect assert in xfs_vm_writepage xfs: use hlist_add_fake xfs: fix a few compiler warnings with CONFIG_XFS_QUOTA=n xfs: tell lockdep about parent iolock usage in filestreams xfs: move delayed write buffer trace xfs: fix per-ag reference counting in inode reclaim tree walking xfs: xfs_ioctl: fix information leak to userland xfs: remove experimental tag from the delaylog option
2010-11-12Documentation: led drivers lp5521 and lp5523Samu Onkalo
Create sub directory Documentation/leds and add short documentation for LP5521 and LP5523 drivers. Signed-off-by: Samu Onkalo <samu.p.onkalo@nokia.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Jean Delvare <khali@linux-fr.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-12led-class: always implement blinkingJohannes Berg
Currently, blinking LEDs can be awkward because it is not guaranteed that all LEDs implement blinking. The trigger that wants it to blink then needs to implement its own timer solution. Rather than require that, add led_blink_set() API that triggers can use. This function will attempt to use hw blinking, but if that fails implements a timer for it. To stop blinking again, brightness_set() also needs to be wrapped into API that will stop the software blink. As a result of this, the timer trigger becomes a very trivial one, and hopefully we can finally see triggers using blinking as well because it's always easy to use. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Acked-by: Richard Purdie <rpurdie@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>