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path: root/fs/char_dev.c
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2010-09-22char: Mark /dev/zero and /dev/kmem as not capable of writebackJan Kara
These devices don't do any writeback but their device inodes still can get dirty so mark bdi appropriately so that bdi code does the right thing and files inodes to lists of bdi carrying the device inodes. Cc: stable@kernel.org Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-06Fix init ordering of /dev/console vs callers of modprobeDavid Howells
Make /dev/console get initialised before any initialisation routine that invokes modprobe because if modprobe fails, it's going to want to open /dev/console, presumably to write an error message to. The problem with that is that if the /dev/console driver is not yet initialised, the chardev handler will call request_module() to invoke modprobe, which will fail, because we never compile /dev/console as a module. This will lead to a modprobe loop, showing the following in the kernel log: request_module: runaway loop modprobe char-major-5-1 request_module: runaway loop modprobe char-major-5-1 request_module: runaway loop modprobe char-major-5-1 request_module: runaway loop modprobe char-major-5-1 request_module: runaway loop modprobe char-major-5-1 This can happen, for example, when the built in md5 module can't find the built in cryptomgr module (because the latter fails to initialise). The md5 module comes before the call to tty_init(), presumably because 'crypto' comes before 'drivers' alphabetically. Fix this by calling tty_init() from chrdev_init(). Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-24fs/char_dev.c: remove useless loopRenzo Davoli
There are two useless lines in fs/char_dev.c. In register_chrdev there is a loop to change all '/' into '!' in the kernel object name. This code is useless as the same substitution is in kobject_set_name_vargs in lib/kobject.c: 228 /* ewww... some of these buggers have '/' in the name ... */ 229 while ((s = strchr(kobj->name, '/'))) 230 s[0] = '!'; kobject_set_name_vargs is called by kobject_set_name. kobject_set_name is called just above the useless loop. [hidave.darkstar@gmail.com: fix warning, remove the unused char *s] Signed-off-by: Renzo Davoli <renzo@cs.unibo.it> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-11Merge 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: (377 commits) ASoC: au1x: PSC-AC97 bugfixes ALSA: dummy - Increase MAX_PCM_SUBSTREAMS to 128 ALSA: dummy - Add debug proc file ALSA: Add const prefix to proc helper functions ALSA: Re-export snd_pcm_format_name() function ALSA: hda - Use auto model for HP laptops with ALC268 codec ALSA: cs46xx - Fix minimum period size ASoC: Fix WM835x Out4 capture enumeration ALSA: Remove unneeded ifdef from sound/core.h ALSA: Remove struct snd_monitor_file from public sound/core.h ASoC: Remove unuused hw_read_t sound: oxygen: work around MCE when changing volume ALSA: dummy - Fake buffer allocations ALSA: hda/realtek: Added support for CLEVO M540R subsystem, 6 channel + digital ASoC: fix pxa2xx-ac97.c breakage ALSA: dummy - Fix the timer calculation in systimer mode ALSA: dummy - Add more description ALSA: dummy - Better jiffies handling ALSA: dummy - Support high-res timer mode ALSA: Release v1.0.21 ...
2009-09-11writeback: add name to backing_dev_infoJens Axboe
This enables us to track who does what and print info. Its main use is catching dirty inodes on the default_backing_dev_info, so we can fix that up. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-08-10chrdev: implement __[un]register_chrdev()Tejun Heo
[un]register_chrdev() assume minor range 0-255. This patch adds __ prefixed versions which take @minorbase and @count explicitly. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2009-07-12headers: smp_lock.h reduxAlexey Dobriyan
* Remove smp_lock.h from files which don't need it (including some headers!) * Add smp_lock.h to files which do need it * Make smp_lock.h include conditional in hardirq.h It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT This will make hardirq.h inclusion cheaper for every PREEMPT=n config (which includes allmodconfig/allyesconfig, BTW) Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11fs: Remove i_cindex from struct inodeTheodore Ts'o
The only user of the i_cindex element in the inode structure is used is by the firewire drivers. As part of an attempt to slim down the inode structure to save memory --- since a typical Linux system will have hundreds of thousands if not millions of inodes cached, a reduction in the size inode has high leverage. The firewire driver does not need i_cindex in any fast path, so it's simple enough to calculate when it is needed, instead of wasting space in the inode structure. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: krh@redhat.com Cc: stefanr@s5r6.in-berlin.de Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-06fs: fix name overwrite in __register_chrdev_region()Cyrill Gorcunov
It's possible to register a chrdev with a name size exactly the same as was allocated in structure. It seems it was not intended behaviour. At least chrdev_show does not like it. Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-23[PATCH] tidy up chrdev_openChristoph Hellwig
Use a single goto label for chrdev_put + return error cases. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-17remove CONFIG_KMOD from fsJohannes Berg
Just always compile the code when the kernel is modular. Convert load_nls to use try_then_request_module to tidy up the code. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-06-20Remove the lock_kernel() call from chrdev_open()Jonathan Corbet
All in-kernel char device open() functions now either have their own lock_kernel() calls or clearly do not need one. Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-06-20Add a comment in chrdev_open()Jonathan Corbet
I stared at this code for a while and almost deleted it before understanding crept into my slow brain. Hopefully this makes life easier for the next person to happen on it. Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-04-29fs: remove unused fops from struct char_device_structJiri Olsa
struct char_device_struct::fops is no longer used: remove it. Signed-off-by: Jiri Olsa <olsajiri@gmail.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08fs/char_dev.c: chrdev_open marked static and removed from fs.hDenis Cheng
There is an outdated comment in serial_core.c also fixed. Signed-off-by: Denis Cheng <crquan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-01-24Kobject: rename kobject_init_ng() to kobject_init()Greg Kroah-Hartman
Now that the old kobject_init() function is gone, rename kobject_init_ng() to kobject_init() to clean up the namespace. Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-01-24Kobject: convert fs/char_dev.c to use kobject_init/add_ng()Greg Kroah-Hartman
This converts the code to use the new kobject functions, cleaning up the logic in doing so. Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-10-17mm: bdi init hooksPeter Zijlstra
provide BDI constructor/destructor hooks [akpm@linux-foundation.org: compile fix] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19unregister_chrdev() return voidAkinobu Mita
unregister_chrdev() does not return meaningful value. This patch makes it return void like most unregister_* functions. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-04-04[PATCH] remove protection of LANANA-reserved majorsAndrew Morton
Revert all this. It can cause device-mapper to receive a different major from earlier kernels and it turns out that the Amanda backup program (via GNU tar, apparently) checks major numbers on files when performing incremental backups. Which is a bit broken of Amanda (or tar), but this feature isn't important enough to justify the churn. Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-20[PATCH] rework reserved major handlingAndrew Morton
Several people have reported failures in dynamic major device number handling due to the recent changes in there to avoid handing out the local/experimental majors. Rolf reports that this is due to a gcc-4.1.0 bug. The patch refactors that code a lot in an attempt to provoke the compiler into behaving. Cc: Rolf Eike Beer <eike-kernel@sf-tec.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12[PATCH] register_chrdev_region() don't hand out the LOCAL/EXPERIMENTAL majorsAndrew Morton
As pointed out in http://bugzilla.kernel.org/show_bug.cgi?id=7922, dynamic chardev major allocation can hand out majors which LANANA has defined as being for local/experimental use. Cc: Torben Mathiasen <device@lanana.org> Cc: Greg KH <greg@kroah.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Tomas Klas <tomas.klas@mepatek.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-09-30[PATCH] BLOCK: Move extern declarations out of fs/*.c into header files [try #6]David Howells
Create a new header file, fs/internal.h, for common definitions local to the sources in the fs/ directory. Move extern definitions that should be in header files from fs/*.c to fs/internal.h or other main header files where they span directories. Signed-Off-By: David Howells <dhowells@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-29[PATCH] cdev documentationJonathan Corbet
Add some documentation comments for the cdev interface. Signed-off-by: Jonathan Corbet <corbet@lwn.net> Cc: Rolf Eike Beer <eike-kernel@sf-tec.de> Acked-by: "Randy.Dunlap" <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29[PATCH] Chardev checking of overlapping rangesAmos Waterland
The code in __register_chrdev_region checks that if the driver wishing to register has the same major as an existing driver the new minor range is strictly less than the existing minor range. However, it does not also check that the new minor range is strictly greater than the existing minor range. That is, if driver X has registered with major=x and minor=0-3, __register_chrdev_region will allow driver Y to register with major=x and minor=1-4. Signed-off-by: Amos Waterland <apw@us.ibm.com> Cc: Linas Vepstas <linas@austin.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27[PATCH] NOMMU: Set BDI capabilities for /dev/mem and /dev/kmemDavid Howells
Set the backing device info capabilities for /dev/mem and /dev/kmem to permit direct sharing under no-MMU conditions and full mapping capabilities under MMU conditions. Make the BDI used by these available to all directly mappable character devices. Also comment the capabilities for /dev/zero. [akpm@osdl.org: ifdef reductions] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-14[PATCH] add function documentation for register_chrdev()Rolf Eike Beer
Documentation for register_chrdev() was missing completely. [akpm@osdl.org: kerneldocification] Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-26[PATCH] devfs: Remove the devfs_fs_kernel.h file from the treeGreg Kroah-Hartman
Also fixes up all files that #include it. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-31[PATCH] Simplify proc/devices and fix early termination regressionJoe Korty
Make baby-simple the code for /proc/devices. Based on the proven design for /proc/interrupts. This also fixes the early-termination regression 2.6.16 introduced, as demonstrated by: # dd if=/proc/devices bs=1 Character devices: 1 mem 27+0 records in 27+0 records out This should also work (but is untested) when /proc/devices >4096 bytes, which I believe is what the original 2.6.16 rewrite fixed. [akpm@osdl.org: cleanups, simplifications] Signed-off-by: Joe Korty <joe.korty@ccur.com> Cc: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28[PATCH] Make most file operations structs in fs/ constArjan van de Ven
This is a conversion to make the various file_operations structs in fs/ const. Basically a regexp job, with a few manual fixups The goal is both to increase correctness (harder to accidentally write to shared datastructures) and reducing the false sharing of cachelines with things that get dirty in .data (while .rodata is nicely read only and thus cache clean) Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28[PATCH] mark f_ops const in the inodeArjan van de Ven
Mark the f_ops members of inodes as const, as well as fix the ripple-through this causes by places that copy this f_ops and then "do stuff" with it. Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-25[PATCH] use kzalloc and kcalloc in core fs codeOliver Neukum
Signed-off-by: Oliver Neukum <oliver@neukum.name> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-20[PATCH] kobj_map semaphore to mutex conversionJes Sorensen
Convert the kobj_map code to use a mutex instead of a semaphore. It converts the single two users as well, genhd.c and char_dev.c. Signed-off-by: Jes Sorensen <jes@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-14[PATCH] convert /proc/devices to use seq_file interfaceNeil Horman
A Christoph suggested that the /proc/devices file be converted to use the seq_file interface. This patch does that. I've obxerved one or two installation that had sufficiently large sans that they overran the 4k limit on /proc/devices. Signed-off-by: Neil Horman <nhorman@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-12[PATCH] cdev: cdev_put oopsBrian King
While fixing an oops in the st driver in a dirty release path, I encountered an oops in cdev_put for cdevs allocated using cdev_alloc. If cdev_del is called when the cdev kobject still has an open user, when the last cdev_put is called, the cdev_put will call kobject_put, which will end up ultimately releasing the cdev in cdev_dynamic_release. Patch fixes the oops by preventing cdev_put from accessing freed memory. Signed-off-by: Brian King <brking@us.ibm.com> Cc: <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-28[PATCH] fix semaphore handling in __unregister_chrdev_regionWen-chien Jesse Sung
This up() should be down() instead. Signed-off-by: Wen-chien Jesse Sung <jesse@cola.voip.idv.tw> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23[PATCH] add check to /proc/devices read routinesNeil Horman
Patch to add check to get_chrdev_list and get_blkdev_list to prevent reads of /proc/devices from spilling over the provided page if more than 4096 bytes of string data are generated from all the registered character and block devices in a system Signed-off-by: Neil Horman <nhorman@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: <viro@parcelfarce.linux.theplanet.co.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05[PATCH] make some things staticAdrian Bunk
This patch makes some needlessly global identifiers static. Signed-off-by: Adrian Bunk <bunk@stusta.de> Acked-by: Arjan van de Ven <arjanv@infradead.org> Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-17[PATCH] revert fs/char_dev.c CONFIG_BASE_FULL changeDavid Brownell
This reverts a fs/char_dev.c patch that was merged into BK on March 3. The problem is that it breaks things ... __register_chrdev_region() has a block of code, commented "temporary" for over two years now, which fails rudely during PCMCIA initialization or other register_chrdev() calls, because it doesn't "degrade to linked list". This keeps whole subsystems from working. A real fix to that "temporary" code should be possible, using some better scheme to allocate major numbers, but it's not something I want to spend time on just now. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Matt Mackall <mpm@selenic.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!