kernel/linux.git/arch/riscv/include/asm/cacheflush.h, branch linux-5.9.y

mm: rename flush_icache_user_range to flush_icache_user_page

2020-06-08T18:05:58+00:00

The function currently known as flush_icache_user_range only operates on a single page. Rename it to flush_icache_user_page as we'll need the name flush_icache_user_range for something else soon. Signed-off-by: Christoph Hellwig Signed-off-by: Andrew Morton Acked-by: Geert Uytterhoeven Cc: Richard Henderson Cc: Ivan Kokshaysky Cc: Matt Turner Cc: Tony Luck Cc: Fenghua Yu Cc: Geert Uytterhoeven Cc: Greentime Hu Cc: Vincent Chen Cc: Jonas Bonn Cc: Stefan Kristiansson Cc: Stafford Horne Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: Paul Walmsley Cc: Palmer Dabbelt Cc: Albert Ou Cc: Arnd Bergmann Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Arnaldo Carvalho de Melo Cc: Mark Rutland Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lkml.kernel.org/r/20200515143646.3857579-20-hch@lst.de Signed-off-by: Linus Torvalds

riscv: use asm-generic/cacheflush.h

2020-06-08T18:05:57+00:00

RISC-V needs almost no cache flushing routines of its own. Rely on asm-generic/cacheflush.h for the defaults. Also remove the pointless __KERNEL__ ifdef while we're at it. Signed-off-by: Christoph Hellwig Signed-off-by: Andrew Morton Reviewed-by: Palmer Dabbelt Acked-by: Palmer Dabbelt Cc: Paul Walmsley Cc: Palmer Dabbelt Cc: Albert Ou Link: http://lkml.kernel.org/r/20200515143646.3857579-18-hch@lst.de Signed-off-by: Linus Torvalds

riscv: Use flush_icache_mm for flush_icache_user_range

2020-03-03T18:28:10+00:00

The only call path is: __access_remote_vm -> copy_to_user_page -> flush_icache_user_range Seems it's ok to use flush_icache_mm instead of flush_icache_all and it could reduce flush_icache_all called on other harts. Signed-off-by: Guo Ren [Palmer: git-am wouldn't apply the patch, I did so manually] Fixes: 08f051eda33b ("RISC-V: Flush I$ when making a dirty page executable") Reviewed-by: Palmer Dabbelt Signed-off-by: Palmer Dabbelt

riscv: fix build break after macro-to-function conversion in generic cacheflush.h

2019-07-18T15:16:56+00:00

Commit c296d4dc13ae ("asm-generic: fix a compilation warning") converted the various flush_*cache_* macros in asm-generic/cacheflush.h to static inline functions. This breaks RISC-V builds, since RISC-V's cacheflush.h includes the generic cacheflush.h and then undefines the macros to be overridden. Fix by copying the subset of the no-op functions that are reused from the generic cacheflush.h into the RISC-V cacheflush.h, and dropping the include of the generic cacheflush.h. Fixes: c296d4dc13ae ("asm-generic: fix a compilation warning") Signed-off-by: Paul Walmsley Cc: Qian Cai Cc: Arnd Bergmann Cc: Andrew Morton Cc: Linus Torvalds

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 286

2019-06-05T15:36:37+00:00

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation version 2 this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 97 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Alexios Zavras Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141901.025053186@linutronix.de Signed-off-by: Greg Kroah-Hartman

riscv: move flush_icache_{all,mm} to cacheflush.c

2019-05-17T03:42:12+00:00

Currently, flush_icache_all is macro-expanded into a SBI call, yet no asm/sbi.h is included in asm/cacheflush.h. This could be moved to mm/cacheflush.c instead (SBI call will dominate performance-wise and there is no worry to not have it inlined. Currently, flush_icache_mm stays in kernel/smp.c, which looks like a hack to prevent it from being compiled when CONFIG_SMP=n. It should also be in mm/cacheflush.c. Signed-off-by: Gary Guo Signed-off-by: Christoph Hellwig Signed-off-by: Palmer Dabbelt

riscv: use NULL instead of a plain 0

2018-06-07T15:01:50+00:00

sbi_remote_sfence_vma() & sbi_remote_fence_i() takes a pointer as first argument but some macros call them with a plain 0 which, while legal C, is frowned upon in the kernel. Change this by replacing the 0 by NULL. Signed-off-by: Luc Van Oostenryck Signed-off-by: Palmer Dabbelt

RISC-V: Allow userspace to flush the instruction cache

2017-11-30T20:58:29+00:00

Despite RISC-V having a direct 'fence.i' instruction available to userspace (which we can't trap!), that's not actually viable when running on Linux because the kernel might schedule a process on another hart. There is no way for userspace to handle this without invoking the kernel (as it doesn't know the thread->hart mappings), so we've defined a RISC-V specific system call to flush the instruction cache. This patch adds both a system call and a VDSO entry. If possible, we'd like to avoid having the system call be considered part of the user-facing ABI and instead restrict that to the VDSO entry -- both just in general to avoid having additional user-visible ABI to maintain, and because we'd prefer that users just call the VDSO entry because there might be a better way to do this in the future (ie, one that doesn't require entering the kernel). Signed-off-by: Andrew Waterman Signed-off-by: Palmer Dabbelt

RISC-V: Flush I$ when making a dirty page executable

2017-11-30T20:58:25+00:00

The RISC-V ISA allows for instruction caches that are not coherent WRT stores, even on a single hart. As a result, we need to explicitly flush the instruction cache whenever marking a dirty page as executable in order to preserve the correct system behavior. Local instruction caches aren't that scary (our implementations actually flush the cache, but RISC-V is defined to allow higher-performance implementations to exist), but RISC-V defines no way to perform an instruction cache shootdown. When explicitly asked to do so we can shoot down remote instruction caches via an IPI, but this is a bit on the slow side. Instead of requiring an IPI to all harts whenever marking a page as executable, we simply flush the currently running harts. In order to maintain correct behavior, we additionally mark every other hart as needing a deferred instruction cache which will be taken before anything runs on it. Signed-off-by: Andrew Waterman Signed-off-by: Palmer Dabbelt

RISC-V: Atomic and Locking Code

2017-09-26T22:26:45+00:00

This contains all the code that directly interfaces with the RISC-V memory model. While this code corforms to the current RISC-V ISA specifications (user 2.2 and priv 1.10), the memory model is somewhat underspecified in those documents. There is a working group that hopes to produce a formal memory model by the end of the year, but my understanding is that the basic definitions we're relying on here won't change significantly. Reviewed-by: Arnd Bergmann Signed-off-by: Palmer Dabbelt