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* Merge branch 'for-linus' of ↵Linus Torvalds2009-12-09
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (42 commits) tree-wide: fix misspelling of "definition" in comments reiserfs: fix misspelling of "journaled" doc: Fix a typo in slub.txt. inotify: remove superfluous return code check hdlc: spelling fix in find_pvc() comment doc: fix regulator docs cut-and-pasteism mtd: Fix comment in Kconfig doc: Fix IRQ chip docs tree-wide: fix assorted typos all over the place drivers/ata/libata-sff.c: comment spelling fixes fix typos/grammos in Documentation/edac.txt sysctl: add missing comments fs/debugfs/inode.c: fix comment typos sgivwfb: Make use of ARRAY_SIZE. sky2: fix sky2_link_down copy/paste comment error tree-wide: fix typos "couter" -> "counter" tree-wide: fix typos "offest" -> "offset" fix kerneldoc for set_irq_msi() spidev: fix double "of of" in comment comment typo fix: sybsystem -> subsystem ...
| * tree-wide: fix assorted typos all over the placeAndré Goddard Rosa2009-12-04
| | | | | | | | | | | | | | | | | | | | That is "success", "unknown", "through", "performance", "[re|un]mapping" , "access", "default", "reasonable", "[con]currently", "temperature" , "channel", "[un]used", "application", "example","hierarchy", "therefore" , "[over|under]flow", "contiguous", "threshold", "enough" and others. Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* | mem_class: Drop the bkl from memory_open()Frederic Weisbecker2009-10-14
|/ | | | | | | | | | | | | | | | | | | | | | The generic open callback for the mem class devices is "protected" by the bkl. Let's look at the datas manipulated inside memory_open: - inode and file: safe - the devlist: safe because it is constant - the memdev classes inside this array are safe too (constant) After we find out which memdev file operation we need to use, we call its open callback. Depending on the targeted memdev, we call either open_port() that doesn't manipulate any racy data (just a capable() check), or we call nothing. So it's safe to remove the big kernel lock there. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> LKML-Reference: <1255113062-5835-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* const: mark struct vm_struct_operationsAlexey Dobriyan2009-09-27
| | | | | | | | | | | * mark struct vm_area_struct::vm_ops as const * mark vm_ops in AGP code But leave TTM code alone, something is fishy there with global vm_ops being used. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* /dev/zero: avoid repeated access_ok() checksNikanth Karthikesan2009-09-24
| | | | | | | | | | In read_zero, we check for access_ok() once for the count bytes. It is unnecessarily checked again in clear_user. Use __clear_user, which does not check for access_ok(). Signed-off-by: Nikanth Karthikesan <knikanth@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Driver-Core: extend devnode callbacks to provide permissionsKay Sievers2009-09-19
| | | | | | | | | | | | | This allows subsytems to provide devtmpfs with non-default permissions for the device node. Instead of the default mode of 0600, null, zero, random, urandom, full, tty, ptmx now have a mode of 0666, which allows non-privileged processes to access standard device nodes in case no other userspace process applies the expected permissions. This also fixes a wrong assignment in pktcdvd and a checkpatch.pl complain. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* mem_class: fix bugJin Dongming2009-09-15
| | | | | | | | | | | | | | | | | | | | | When I build and boot -next on fedora 10, I can not login anymore. When I input the user name and password, the system does not output any message and requires user to input the user name and password again and again. I find the patch which caused this problem with "GIT BISECT" command. And the patch is commit 7c4b7daa1878972ed0137c95f23569124bd6e2b1 "mem_class: use minor as index instead of searching the array". Though I don't know the real reason why user could not login, I confirmed the patch I made as following could resolve the problem on fedora 10. Signed-off-by: Jin Dongming <jin.dongming@np.css.fujitsu.com> Acked-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* mem_class: use minor as index instead of searching the arrayKay Sievers2009-09-15
| | | | | | | | | Declare the device list with the minor numbers as the index, which saves us from searching for a matching list entry. Remove old devfs permissions declaration. Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* writeback: add name to backing_dev_infoJens Axboe2009-09-11
| | | | | | | | 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>
* drivers/char/mem.c: memory_open() cleanup: lookup minor device number from ↵Adriano dos Santos Fernandes2009-06-18
| | | | | | | | | | | | | | | devlist memory_open() ignores devlist and does a switch for each item, duplicating code and conditional definitions. Clean it up by adding backing_dev_info to devlist and use it to lookup for the minor device. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Adriano dos Santos Fernandes <adrianosf@uol.com.br> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Make /dev/zero reads interruptible by signalsLinus Torvalds2009-06-09
| | | | | | | | | | | | This helps with bad latencies for large reads from /dev/zero, but might conceivably break some application that "knows" that a read of /dev/zero cannot return early. So do this early in the merge window to give us maximal test coverage, even if the patch is totally trivial. Obviously, no well-behaved application should ever depend on the read being uninterruptible, but hey, bugs happen. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* drivers/char/mem.c: avoid OOM lockup during large reads from /dev/zeroSalman Qazi2009-06-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While running 20 parallel instances of dd as follows: #!/bin/bash for i in `seq 1 20`; do dd if=/dev/zero of=/export/hda3/dd_$i bs=1073741824 count=1 & done wait on a 16G machine, we noticed that rather than just killing the processes, the entire kernel went down. Stracing dd reveals that it first does an mmap2, which makes 1GB worth of zero page mappings. Then it performs a read on those pages from /dev/zero, and finally it performs a write. The machine died during the reads. Looking at the code, it was noticed that /dev/zero's read operation had been changed by 557ed1fa2620dc119adb86b34c614e152a629a80 ("remove ZERO_PAGE") from giving zero page mappings to actually zeroing the page. The zeroing of the pages causes physical pages to be allocated to the process. But, when the process exhausts all the memory that it can, the kernel cannot kill it, as it is still in the kernel mode allocating more memory. Consequently, the kernel eventually crashes. To fix this, I propose that when a fatal signal is pending during /dev/zero read operation, we simply return and let the user process die. Signed-off-by: Salman Qazi <sqazi@google.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> [ Modified error return and comment trivially. - Linus] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86, PAT: Remove duplicate memtype reserve in devmem mmapSuresh Siddha2009-04-10
| | | | | | | | | | | | /dev/mem mmap code was doing memtype reserve/free for a while now. Recently we added memtype tracking in remap_pfn_range, and /dev/mem mmap uses it indirectly. So, we don't need seperate tracking in /dev/mem code any more. That means another ~100 lines of code removed :-). Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> LKML-Reference: <20090409212709.085210000@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* mm: make vread() and vwrite() declarationKOSAKI Motohiro2009-01-06
| | | | | | | | | | | | | Sparse output following warnings. mm/vmalloc.c:1436:6: warning: symbol 'vread' was not declared. Should it be static? mm/vmalloc.c:1474:6: warning: symbol 'vwrite' was not declared. Should it be static? However, it is used by /dev/kmem. fixed here. Signed-off-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>
* device create: char: convert device_create_drvdata to device_createGreg Kroah-Hartman2008-10-16
| | | | | | | | Now that device_create() has been audited, rename things back to the original call to be sane. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* use generic_access_phys for /dev/mem mappingsRik van Riel2008-07-24
| | | | | | | | | | | | | | | Use generic_access_phys as the access_process_vm access function for /dev/mem mappings. This makes it possible to debug the X server. [akpm@linux-foundation.org: repair all the architectures which broke] Signed-off-by: Rik van Riel <riel@redhat.com> Cc: Benjamin Herrensmidt <benh@kernel.crashing.org> Cc: Dave Airlie <airlied@linux.ie> Cc: Hugh Dickins <hugh@veritas.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* device create: char: convert device_create to device_create_drvdataGreg Kroah-Hartman2008-07-22
| | | | | | | | device_create() is race-prone, so use the race-free device_create_drvdata() instead as device_create() is going away. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Subject: devmem, x86: fix rename of CONFIG_NONPROMISC_DEVMEMIngo Molnar2008-07-20
| | | | | | | | | | | | | | | | | | | From: Arjan van de Ven <arjan@infradead.org> Date: Sat, 19 Jul 2008 15:47:17 -0700 CONFIG_NONPROMISC_DEVMEM was a rather confusing name - but renaming it to CONFIG_PROMISC_DEVMEM causes problems on architectures that do not support this feature; this patch renames it to CONFIG_STRICT_DEVMEM, so that architectures can opt-in into it. ( the polarity of the option is still the same as it was originally; it needs to be for now to not break architectures that don't have the infastructure yet to support this feature) Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: "V.Radhakrishnan" <rk@atr-labs.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> ---
* x86: rename CONFIG_NONPROMISC_DEVMEM to CONFIG_PROMISC_DEVMEMIngo Molnar2008-07-17
| | | | | | | | | | | | | | | | Linus observed: > The real bug is that we shouldn't have "double negatives", and > certainly not negative config options. Making that "promiscuous > /dev/mem" option a negated thing as a config option was bad. right ... lets rename this option. There should never be a negation in config options. [ that reminds me of CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER, but that is for another commit ;-) ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
* mem: cdev lock_kernel() pushdownJonathan Corbet2008-06-20
| | | | | | | It's really hard to tell if this is necessary - lots of weird magic happens by way of map_devmem() Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* make /dev/kmem a config optionArjan van de Ven2008-04-29
| | | | | | | | | | | | | | | Make /dev/kmem a config option; /dev/kmem is VERY rarely used, and when used, it's generally for no good (rootkits tend to be the most common users). With this config option, users have the choice to disable /dev/kmem, saving some size as well. A patch to disable /dev/kmem has been in the Fedora and RHEL kernels for 4+ years now without any known problems or legit users of /dev/kmem. [akpm@linux-foundation.org: make CONFIG_DEVKMEM default to y] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86: PAT use reserve free memtype in mmap of /dev/memvenkatesh.pallipadi@intel.com2008-04-24
| | | | | | | | | | Use reserve_memtype and free_memtype wrappers for /dev/mem mmaps. The memtype is slightly complicated here, given that we have to support existing X mappings. We fallback on UC_MINUS for that. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: PAT phys_mem_access_prot_allowed for dev/mem mmapvenkatesh.pallipadi@intel.com2008-04-24
| | | | | | | | | | | | | | Introduce phys_mem_access_prot_allowed(), which checks whether the mapping is possible, without any conflicts and returns success or failure based on that. phys_mem_access_prot() by itself does not allow failure case. This ability to return error is needed for PAT where we may have aliasing conflicts. x86 setup __HAVE_PHYS_MEM_ACCESS_PROT and move x86 specific code out of /dev/mem into arch specific area. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: PAT avoid aliasing in /dev/mem read/writevenkatesh.pallipadi@intel.com2008-04-24
| | | | | | | | | Add xlate and unxlate around /dev/mem read/write. This sets up the mapping that can be used for /dev/mem read and write without aliasing worries. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* devmem: add range_is_allowed() check to mmap of /dev/memVenki Pallipadi2008-04-24
| | | | | | | | | | | | Earlier patch that introduced CONFIG_NONPROMISC_DEVMEM, did the range_is_allowed() check only for read and write. Add range_is_allowed() check to mmap of /dev/mem as well. Changes the paramaters of range_is_allowed() to pfn and size to handle more than 32 bits of physical address on 32 bit arch cleanly. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: introduce /dev/mem restrictions with a config optionArjan van de Ven2008-04-24
| | | | | | | | | | | | | | | | | | | | | | | This patch introduces a restriction on /dev/mem: Only non-memory can be read or written unless the newly introduced config option is set. The X server needs access to /dev/mem for the PCI space, but it doesn't need access to memory; both the file permissions and SELinux permissions of /dev/mem just make X effectively super-super powerful. With the exception of the BIOS area, there's just no valid app that uses /dev/mem on actual memory. Other popular users of /dev/mem are rootkits and the like. (note: mmap access of memory via /dev/mem was already not allowed since a really long time) People who want to use /dev/mem for kernel debugging can enable the config option. The restrictions of this patch have been in the Fedora and RHEL kernels for at least 4 years without any problems. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* x86 merge fallout: umlAl Viro2007-10-29
| | | | | | | | Don't undef __i386__/__x86_64__ in uml anymore, make sure that (few) places that required adjusting the ifdefs got those. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: bdi init hooksPeter Zijlstra2007-10-17
| | | | | | | | | 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>
* remove ZERO_PAGENick Piggin2007-10-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The commit b5810039a54e5babf428e9a1e89fc1940fabff11 contains the note A last caveat: the ZERO_PAGE is now refcounted and managed with rmap (and thus mapcounted and count towards shared rss). These writes to the struct page could cause excessive cacheline bouncing on big systems. There are a number of ways this could be addressed if it is an issue. And indeed this cacheline bouncing has shown up on large SGI systems. There was a situation where an Altix system was essentially livelocked tearing down ZERO_PAGE pagetables when an HPC app aborted during startup. This situation can be avoided in userspace, but it does highlight the potential scalability problem with refcounting ZERO_PAGE, and corner cases where it can really hurt (we don't want the system to livelock!). There are several broad ways to fix this problem: 1. add back some special casing to avoid refcounting ZERO_PAGE 2. per-node or per-cpu ZERO_PAGES 3. remove the ZERO_PAGE completely I will argue for 3. The others should also fix the problem, but they result in more complex code than does 3, with little or no real benefit that I can see. Why? Inserting a ZERO_PAGE for anonymous read faults appears to be a false optimisation: if an application is performance critical, it would not be doing many read faults of new memory, or at least it could be expected to write to that memory soon afterwards. If cache or memory use is critical, it should not be working with a significant number of ZERO_PAGEs anyway (a more compact representation of zeroes should be used). As a sanity check -- mesuring on my desktop system, there are never many mappings to the ZERO_PAGE (eg. 2 or 3), thus memory usage here should not increase much without it. When running a make -j4 kernel compile on my dual core system, there are about 1,000 mappings to the ZERO_PAGE created per second, but about 1,000 ZERO_PAGE COW faults per second (less than 1 ZERO_PAGE mapping per second is torn down without being COWed). So removing ZERO_PAGE will save 1,000 page faults per second when running kbuild, while keeping it only saves less than 1 page clearing operation per second. 1 page clear is cheaper than a thousand faults, presumably, so there isn't an obvious loss. Neither the logical argument nor these basic tests give a guarantee of no regressions. However, this is a reasonable opportunity to try to remove the ZERO_PAGE from the pagefault path. If it is found to cause regressions, we can reintroduce it and just avoid refcounting it. The /dev/zero ZERO_PAGE usage and TLB tricks also get nuked. I don't see much use to them except on benchmarks. All other users of ZERO_PAGE are converted just to use ZERO_PAGE(0) for simplicity. We can look at replacing them all and maybe ripping out ZERO_PAGE completely when we are more satisfied with this solution. Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus "snif" Torvalds <torvalds@linux-foundation.org>
* Merge branch 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linusLinus Torvalds2007-07-10
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus: (62 commits) [MIPS] PNX8550: Cleanup proc code. [MIPS] WRPPMC: Fix build. [MIPS] Yosemite: Fix modpost warnings. [MIPS] Change names of local variables to silence sparse [MIPS] SB1: Fix modpost warning. [MIPS] PNX: Fix modpost warnings. [MIPS] Alchemy: Fix modpost warnings. [MIPS] Non-FPAFF: Fix warning. [MIPS] DEC: Fix modpost warning. [MIPS] MIPSsim: Enable MIPSsim virtual network driver. [MIPS] Delete Ocelot 3 support. [MIPS] remove LASAT Networks platforms support [MIPS] Early check for SMTC kernel on non-MT processor [MIPS] Add debugfs files to show fpuemu statistics [MIPS] Add some debugfs files to debug unaligned accesses [MIPS] rbtx4938: Fix secondary PCIC and glue internal NICs [MIPS] tc35815: Load MAC address via platform_device [MIPS] Move FPU affinity code into separate file. [MIPS] Make ioremap() work on TX39/49 special unmapped segment [MIPS] rbtx4938: Update and minimize defconfig ...
| * [MIPS] Hook for platforms to define cachability of /dev/mem regionsRalf Baechle2007-07-10
| | | | | | | | Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* | splice: divorce the splice structure/function definitions from the pipe headerJens Axboe2007-07-10
|/ | | | | | | | | We need to move even more stuff into the header so that folks can use the splice_to_pipe() implementation instead of open-coding a lot of pipe knowledge (see relay implementation), so move to our own header file finally. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Make /dev/port conditional on config symbolRussell King2007-05-08
| | | | | | | | | | Instead of having /dev/port support dependent in multiple places on a string of preprocessor symbols, define a new configuration directive for it. This ensures that all four places remain consistent with each other. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* header cleaning: don't include smp_lock.h when not usedRandy Dunlap2007-05-08
| | | | | | | | | | | | Remove includes of <linux/smp_lock.h> where it is not used/needed. Suggested by Al Viro. Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc, sparc64, and arm (all 59 defconfigs). Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fix bogon in /dev/mem mmap'ing on nommuBenjamin Herrenschmidt2007-04-17
| | | | | | | | | | | | While digging through my MAP_FIXED changes, I found that rather obvious bug in /dev/mem mmap implementation for nommu archs. get_unmapped_area() is expected to return an address, not a pfn. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-By: David Howells <dhowells@redhat.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Revert "[PATCH] Fix up mmap_kmem"Linus Torvalds2007-01-22
| | | | | | | | | | | | | | | | | | | | | This reverts commit 99a10a60ba9bedcf5d70ef81414d3e03816afa3f. As per Hugh Dickins: "Nadia Derbey has reported that mmap of /dev/kmem no longer works with the kernel virtual address as offset, and Franck has confirmed that his patch came from a misunderstanding of what an offset means to /dev/kmem - whereas his patch description seems to say that he was correcting the offset on a few plaforms, there was no such problem to correct, and his patch was in fact changing its API on all platforms." Suggested-by: Hugh Dickins <hugh@veritas.com> Cc: Franck Bui-Huu <fbuihuu@gmail.com> Cc: Nadia Derbey <Nadia.Derbey@bull.net> Cc: Andi Kleen <ak@suse.de> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] read_zero_pagealigned() locking fixHugh Dickins2006-12-10
| | | | | | | | | | | | | | | | | | | | | | | | | Ramiro Voicu hits the BUG_ON(!pte_none(*pte)) in zeromap_pte_range: kernel bugzilla 7645. Right: read_zero_pagealigned uses down_read of mmap_sem, but another thread's racing read of /dev/zero, or a normal fault, can easily set that pte again, in between zap_page_range and zeromap_page_range getting there. It's been wrong ever since 2.4.3. The simple fix is to use down_write instead, but that would serialize reads of /dev/zero more than at present: perhaps some app would be badly affected. So instead let zeromap_page_range return the error instead of BUG_ON, and read_zero_pagealigned break to the slower clear_user loop in that case - there's no need to optimize for it. Use -EEXIST for when a pte is found: BUG_ON in mmap_zero (the other user of zeromap_page_range), though it really isn't interesting there. And since mmap_zero wants -EAGAIN for out-of-memory, the zeromaps better return that than -ENOMEM. Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: Ramiro Voicu: <Ramiro.Voicu@cern.ch> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] struct path: convert char-driversJosef Sipek2006-12-08
| | | | | | Signed-off-by: Josef Sipek <jsipek@fsl.cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Driver core: change mem class_devices to be real devicesGreg Kroah-Hartman2006-12-01
| | | | | Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Include proper header file for PFN_DOWN()Linus Torvalds2006-10-13
| | | | | | | | The recent commit (99a10a60ba9bedcf5d70ef81414d3e03816afa3f) to fix up mmap_kmem() broke compiles because it used PFN_DOWN() without including <linux/pfn.h>. Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Fix up mmap_kmemFranck Bui-Huu2006-10-13
| | | | | | | | | | | | | | | | | | | | | | | vma->vm_pgoff is an pfn _offset_ relatif to the begining of the memory start. The previous code was doing at first: vma->vm_pgoff << PAGE_SHIFT which results into a wrong physical address since some platforms have a physical mem start that can be different from 0. After that the previous call __pa() on this wrong physical address, however __pa() is used to convert a _virtual_ address into a physical one. This patch rewrites this convertion. It calculates the pfn of PAGE_OFFSET which is the pfn of the mem start then it adds the vma->vm_pgoff to it. It also uses virt_to_phys() instead of __pa() since the latter shouldn't be used by drivers. Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] mem driver: fix conditional on isa i/o supportGeoff Levand2006-09-29
| | | | | | | | | | | | | | | | This change corrects the logic on the preprocessor conditionals that include support for ISA port i/o (/dev/ioports) into the mem character driver. This fixes the following error when building for powerpc platforms with CONFIG_PCI=n. drivers/built-in.o: undefined reference to `pci_io_base' Signed-off-by: Geoff Levand <geoffrey.levand@am.sony.com> Acked-by: Linas Vepstas <lins@austin.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] NOMMU: Set BDI capabilities for /dev/mem and /dev/kmemDavid Howells2006-09-27
| | | | | | | | | | | | | | 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>
* [PATCH] make valid_mmap_phys_addr_range() take a pfnLennert Buytenhek2006-07-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Newer ARMs have a 40 bit physical address space, but mapping physical memory above 4G needs a special page table format which we (currently?) do not use for userspace mappings, so what happens instead is that mapping an address >= 4G will happily discard the upper bits and wrap. There is a valid_mmap_phys_addr_range() arch hook where we could check for >= 4G addresses and deny the mapping, but this hook takes an unsigned long address: static inline int valid_mmap_phys_addr_range(unsigned long addr, size_t size); And drivers/char/mem.c:mmap_mem() calls it like this: static int mmap_mem(struct file * file, struct vm_area_struct * vma) { size_t size = vma->vm_end - vma->vm_start; if (!valid_mmap_phys_addr_range(vma->vm_pgoff << PAGE_SHIFT, size)) So that's not much help either. This patch makes the hook take a pfn instead of a phys address. Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org> Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] make more file_operation structs staticArjan van de Ven2006-07-03
| | | | | | | | | | | | Mark the static struct file_operations in drivers/char as const. Making them const prevents accidental bugs, and moves them to the .rodata section so that they no longer do any false sharing; in addition with the proper debug option they are then protected against corruption.. [akpm@osdl.org: build fix] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Remove obsolete #include <linux/config.h>Jörn Engel2006-06-30
| | | | | Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [PATCH] devfs: Remove the devfs_fs_kernel.h file from the treeGreg Kroah-Hartman2006-06-26
| | | | | | Also fixes up all files that #include it. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] devfs: Remove devfs_mk_cdev() function from the kernel treeGreg Kroah-Hartman2006-06-26
| | | | | | Removes the devfs_mk_cdev() function and all callers of it. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [PATCH] splice: add ->splice_write support for /dev/nullJens Axboe2006-04-26
| | | | | | Useful for testing. Signed-off-by: Jens Axboe <axboe@suse.de>
* [PATCH] mark f_ops const in the inodeArjan van de Ven2006-03-28
| | | | | | | | | | | 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>
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