aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm/include/asm/fixmap.h (follow)
AgeCommit message (Collapse)AuthorFilesLines
2015-08-18ARM: 8415/1: early fixmap support for earlyconStefan Agner1-1/+14
Add early fixmap support, initially to support permanent, fixed mapping support for early console. A temporary, early pte is created which is migrated to a permanent mapping in paging_init. This is also needed since the attributes may change as the memory types are initialized. The 3MiB range of fixmap spans two pte tables, but currently only one pte is created for early fixmap support. Re-add FIX_KMAP_BEGIN to the index calculation in highmem.c since the index for kmap does not start at zero anymore. This reverts 4221e2e6b316 ("ARM: 8031/1: fixmap: remove FIX_KMAP_BEGIN and FIX_KMAP_END") to some extent. Cc: Mark Salter <msalter@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-10-16arm: use fixmap for text patching when text is RORabin Vincent1-0/+4
Use fixmaps for text patching when the kernel text is read-only, inspired by x86. This makes jump labels and kprobes work with the currently available CONFIG_DEBUG_SET_MODULE_RONX and the upcoming CONFIG_DEBUG_RODATA options. Signed-off-by: Rabin Vincent <rabin@rab.in> [kees: fixed up for merge with "arm: use generic fixmap.h"] [kees: added parse acquire/release annotations to pass C=1 builds] [kees: always use stop_machine to keep TLB flushing local] Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Nicolas Pitre <nico@linaro.org>
2014-10-16arm: fixmap: implement __set_fixmap()Kees Cook1-0/+2
This is used from set_fixmap() and clear_fixmap() via asm-generic/fixmap.h. Also makes sure that the fixmap allocation fits into the expected range. Based on patch by Rabin Vincent. Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Rabin Vincent <rabin@rab.in> Acked-by: Nicolas Pitre <nico@linaro.org>
2014-10-16ARM: expand fixmap region to 3MBRob Herring1-1/+1
With commit a05e54c103b0 ("ARM: 8031/2: change fixmap mapping region to support 32 CPUs"), the fixmap region was expanded to 2MB, but it precluded any other uses of the fixmap region. In order to support other uses the fixmap region needs to be expanded beyond 2MB. Fortunately, the adjacent 1MB range 0xffe00000-0xfff00000 is availabe. Remove fixmap_page_table ptr and lookup the page table via the virtual address so that the fixmap region can span more that one pmd. The 2nd pmd is already created since it is shared with the vector page. Signed-off-by: Rob Herring <robh@kernel.org> [kees: fixed CONFIG_DEBUG_HIGHMEM get_fixmap() calls] [kees: moved pte allocation outside of CONFIG_HIGHMEM] Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Nicolas Pitre <nico@linaro.org>
2014-10-16arm: use generic fixmap.hMark Salter1-18/+9
ARM is different from other architectures in that fixmap pages are indexed with a positive offset from FIXADDR_START. Other architectures index with a negative offset from FIXADDR_TOP. In order to use the generic fixmap.h definitions, this patch redefines FIXADDR_TOP to be inclusive of the useable range. That is, FIXADDR_TOP is the virtual address of the topmost fixed page. The newly defined FIXADDR_END is the first virtual address past the fixed mappings. Signed-off-by: Mark Salter <msalter@redhat.com> Reviewed-by: Doug Anderson <dianders@chromium.org> [kees: update for a05e54c103b0 ("ARM: 8031/2: change fixmap ...")] Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Rob Herring <robh@kernel.org> Acked-by: Nicolas Pitre <nico@linaro.org>
2014-04-23ARM: 8031/2: change fixmap mapping region to support 32 CPUsLiu Hua1-14/+2
In 32-bit ARM systems, the fixmap mapping region can support no more than 14 CPUs(total: 896k; one CPU: 64K). And we can configure NR_CPUS up to 32. So there is a mismatch. This patch moves fixmapping region downwards to region 0xffc00000- 0xffe00000. Then the fixmap mapping region can support up to 32 CPUs. Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Liu Hua <sdu.liu@huawei.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-04-23ARM: 8031/1: fixmap: remove FIX_KMAP_BEGIN and FIX_KMAP_ENDLiu Hua1-3/+2
It seems that these two macros are not used by non architecture specific code. And on ARM FIX_KMAP_BEGIN equals zero. This patch removes these two macros. Instead, using FIX_KMAP_NR_PTES to tell the pte number belonged to fixmap mapping region. The code will become clearer when I introduce a bugfix on fixmap mapping region. Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Liu Hua <sdu.liu@huawei.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2009-03-15[ARM] fixmap supportNicolas Pitre1-0/+41
This is the minimum fixmap interface expected to be implemented by architectures supporting highmem. We have a second level page table already allocated and covering 0xfff00000-0xffffffff because the exception vector page is located at 0xffff0000, and various cache tricks already use some entries above 0xffff0000. Therefore the PTEs covering 0xfff00000-0xfffeffff are free to be used. However the XScale cache flushing code already uses virtual addresses between 0xfffe0000 and 0xfffeffff. So this reserves the 0xfff00000-0xfffdffff range for fixmap stuff. The Documentation/arm/memory.txt information is updated accordingly, including the information about the actual top of DMA memory mapping region which didn't match the code. Signed-off-by: Nicolas Pitre <nico@marvell.com>