On Fri 17 May 09:47 PDT 2019, Stephen Boyd wrote: > This patch series implements a read-only version of memremap() via > a new MEMREMAP_RO flag. If this is passed in the mapping call, we'll > try to map the memory region as read-only if it doesn't intersect > with an existing mapping. Otherwise, we'll try to fallback to other > flags to try to map the memory that way. > > The main use case I have is to map the command-db memory region on > Qualcomm devices with a read-only mapping. It's already a const marked > pointer and the API returns const pointers as well, so this series makes > sure that even stray writes can't modify the memory. To get there we > introduce a devm version of memremap() for a reserved memory region, add > a memremap() flag, and implement support for that flag on arm64. > I have a few places where the first patch will be useful, and the rest looks good. Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> Regards, Bjorn > Cc: Evan Green <evgreen@xxxxxxxxxxxx> > Cc: Rob Herring <robh+dt@xxxxxxxxxx> > Cc: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> > Cc: Andy Gross <agross@xxxxxxxxxx> > Cc: Will Deacon <will.deacon@xxxxxxx> > Cc: Catalin Marinas <catalin.marinas@xxxxxxx> > > Stephen Boyd (5): > reserved_mem: Add a devm_memremap_reserved_mem() API > soc: qcom: cmd-db: Migrate to devm_memremap_reserved_mem() > memremap: Add support for read-only memory mappings > arm64: Add support for arch_memremap_ro() > soc: qcom: cmd-db: Map with read-only mappings > > arch/arm64/include/asm/io.h | 1 + > drivers/of/of_reserved_mem.c | 45 +++++++++++++++++++++++++++++++++ > drivers/soc/qcom/cmd-db.c | 14 +++------- > include/linux/io.h | 1 + > include/linux/of_reserved_mem.h | 6 +++++ > kernel/iomem.c | 15 +++++++++-- > 6 files changed, 70 insertions(+), 12 deletions(-) > > > base-commit: 9e98c678c2d6ae3a17cb2de55d17f69dddaa231b > prerequisite-patch-id: 62119e27c0c0686e02f0cb55c296b878fb7f5e47 > prerequisite-patch-id: bda32cfc1733c245ae3f141d7c27b18e4adcc628 > prerequisite-patch-id: b8f8097161bd15e87d54dcfbfa67b9ca1abc7204 > -- > Sent by a computer through tubes >
