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2012-12-13MIPS: Highmem: Fix build error if CONFIG_DEBUG_HIGHMEM is disabledRalf Baechle
CC arch/mips/mm/highmem.o /home/ralf/src/linux/linux-mips/arch/mips/mm/highmem.c: In function ‘__kunmap_atomic’: /home/ralf/src/linux/linux-mips/arch/mips/mm/highmem.c:70:6: error: variable ‘type’ set but not used [-Werror=unused-but-set-variable] cc1: all warnings being treated as errors This warning exists in gcc 4.6.0 and newer. Kernels 2.6.40 and newer use -Wunused-but-set-variable to suppress it. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-03-20highmem: kill all __kmap_atomic()Cong Wang
[swarren@nvidia.com: highmem: Fix ARM build break due to __kmap_atomic rename] Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Cong Wang <amwang@redhat.com>
2010-10-27mm: fix race in kunmap_atomic()Peter Zijlstra
Christoph reported a nice splat which illustrated a race in the new stack based kmap_atomic implementation. The problem is that we pop our stack slot before we're completely done resetting its state -- in particular clearing the PTE (sometimes that's CONFIG_DEBUG_HIGHMEM). If an interrupt happens before we actually clear the PTE used for the last slot, that interrupt can reuse the slot in a dirty state, which triggers a BUG in kmap_atomic(). Fix this by introducing kmap_atomic_idx() which reports the current slot index without actually releasing it and use that to find the PTE and delay the _pop() until after we're completely done. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reported-by: Christoph Hellwig <hch@infradead.org> Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26mm: stack based kmap_atomic()Peter Zijlstra
Keep the current interface but ignore the KM_type and use a stack based approach. The advantage is that we get rid of crappy code like: #define __KM_PTE \ (in_nmi() ? KM_NMI_PTE : \ in_irq() ? KM_IRQ_PTE : \ KM_PTE0) and in general can stop worrying about what context we're in and what kmap slots might be appropriate for that. The downside is that FRV kmap_atomic() gets more expensive. For now we use a CPP trick suggested by Andrew: #define kmap_atomic(page, args...) __kmap_atomic(page) to avoid having to touch all kmap_atomic() users in a single patch. [ not compiled on: - mn10300: the arch doesn't actually build with highmem to begin with ] [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: fix up drivers/gpu/drm/i915/intel_overlay.c] Acked-by: Rik van Riel <riel@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Chris Metcalf <cmetcalf@tilera.com> Cc: David Howells <dhowells@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: David Miller <davem@davemloft.net> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dave Airlie <airlied@linux.ie> Cc: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-09kmap_atomic: make kunmap_atomic() harder to misuseCesar Eduardo Barros
kunmap_atomic() is currently at level -4 on Rusty's "Hard To Misuse" list[1] ("Follow common convention and you'll get it wrong"), except in some architectures when CONFIG_DEBUG_HIGHMEM is set[2][3]. kunmap() takes a pointer to a struct page; kunmap_atomic(), however, takes takes a pointer to within the page itself. This seems to once in a while trip people up (the convention they are following is the one from kunmap()). Make it much harder to misuse, by moving it to level 9 on Rusty's list[4] ("The compiler/linker won't let you get it wrong"). This is done by refusing to build if the type of its first argument is a pointer to a struct page. The real kunmap_atomic() is renamed to kunmap_atomic_notypecheck() (which is what you would call in case for some strange reason calling it with a pointer to a struct page is not incorrect in your code). The previous version of this patch was compile tested on x86-64. [1] http://ozlabs.org/~rusty/index.cgi/tech/2008-04-01.html [2] In these cases, it is at level 5, "Do it right or it will always break at runtime." [3] At least mips and powerpc look very similar, and sparc also seems to share a common ancestor with both; there seems to be quite some degree of copy-and-paste coding here. The include/asm/highmem.h file for these three archs mention x86 CPUs at its top. [4] http://ozlabs.org/~rusty/index.cgi/tech/2008-03-30.html [5] As an aside, could someone tell me why mn10300 uses unsigned long as the first parameter of kunmap_atomic() instead of void *? Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net> Cc: Russell King <linux@arm.linux.org.uk> (arch/arm) Cc: Ralf Baechle <ralf@linux-mips.org> (arch/mips) Cc: David Howells <dhowells@redhat.com> (arch/frv, arch/mn10300) Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> (arch/mn10300) Cc: Kyle McMartin <kyle@mcmartin.ca> (arch/parisc) Cc: Helge Deller <deller@gmx.de> (arch/parisc) Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> (arch/parisc) Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> (arch/powerpc) Cc: Paul Mackerras <paulus@samba.org> (arch/powerpc) Cc: "David S. Miller" <davem@davemloft.net> (arch/sparc) Cc: Thomas Gleixner <tglx@linutronix.de> (arch/x86) Cc: Ingo Molnar <mingo@redhat.com> (arch/x86) Cc: "H. Peter Anvin" <hpa@zytor.com> (arch/x86) Cc: Arnd Bergmann <arnd@arndb.de> (include/asm-generic) Cc: Rusty Russell <rusty@rustcorp.com.au> ("Hard To Misuse" list) Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-02-22MIPS: Highmem: Fix build errorYoichi Yuasa
arch/mips/mm/highmem.c: In function 'kmap_init': arch/mips/mm/highmem.c:130: error: 'init_mm' undeclared (first use in this function) arch/mips/mm/highmem.c:130: error: (Each undeclared identifier is reported only once arch/mips/mm/highmem.c:130: error: for each function it appears in.) Signed-off-by: Yoichi Yuasa <yuasa@linux-mips.org> Cc: linux-mips <linux-mips@linux-mips.org> Patchwork: http://patchwork.linux-mips.org/patch/980/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-06-24MIPS: Build fix - include <linux/smp.h> into all smp_processor_id() users.Ralf Baechle
Some of the were relying into smp.h being dragged in by another header which of course is fragile. <asm/cpu-info.h> uses smp_processor_id() only in macros and including smp.h there leads to an include loop, so don't change cpu-info.h. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-05-14MIPS: Fix highmem.Ralf Baechle
Commit 351336929ccf222ae38ff0cb7a8dd5fd5c6236a0 (kernel.org) rsp. b3594a089f1c17ff919f8f78505c3f20e1f6f8ce (linux-mips.org): > From: Chris Dearman <chris@mips.com> > Date: Wed, 19 Sep 2007 00:58:24 +0100 > Subject: [PATCH] [MIPS] Allow setting of the cache attribute at run time. > > Slightly tacky, but there is a precedent in the sparc archirecture code. introduces the variable _page_cachable_default, which defaults to zero and. is used to create the prototype PTE for __kmap_atomic in arch/mips/mm/init.c:kmap_init before initialization in arch/mips/mm/c-r4k.c:coherency_setup, so the default value of 0 will be used as the CCA of kmap atomic pages which on many processors is not a defined CCA value and may result in writes to kmap_atomic pages getting corrupted. Debugged by Jon Fraser (jfraser@broadcom.com). Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-04-01mm: use debug_kmap_atomicAkinobu Mita
Use debug_kmap_atomic in kmap_atomic, kmap_atomic_pfn, and iomap_atomic_prot_pfn. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-30MIPS: Use BUG_ON() where possible.Ralf Baechle
Based on original patch by Stoyan Gaydarov <stoyboyker@gmail.com> which missed a few places. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2008-05-12[MIPS] unexport __kmap_atomic_to_pageAdrian Bunk
This patch removes the no longer used export of __kmap_atomic_to_page. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-05-11[MIPS] Remove LIMITED_DMA supportFranck Bui-Huu
This code was needed only by Jaguar ATX. Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2006-12-07[PATCH] mm: pagefault_{disable,enable}()Peter Zijlstra
Introduce pagefault_{disable,enable}() and use these where previously we did manual preempt increments/decrements to make the pagefault handler do the atomic thing. Currently they still rely on the increased preempt count, but do not rely on the disabled preemption, this might go away in the future. (NOTE: the extra barrier() in pagefault_disable might fix some holes on machines which have too many registers for their own good) [heiko.carstens@de.ibm.com: s390 fix] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Nick Piggin <npiggin@suse.de> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> 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>
2006-04-19[MIPS] Fix CONFIG_LIMITED_DMA build.Ralf Baechle
This fix a build error for the Momentum Jaguar ATX eval board. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2005-10-29Define kmap_atomic_pfn() for MIPS.Ralf Baechle
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2005-04-16Linux-2.6.12-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!