The pmem api is responsible for shepherding data out to persistent media. The pmem driver uses this api, when available, to assert that data is durable by the time bio_endio() is invoked. When an architecture or cpu can not make persistence guarantees the driver warns and falls back to "best effort" implementation. Changes since v1 [1]: 1/ Rebase on tip/master + Toshi's ioremap_wt() patches and enable ioremap_cache() to be used generically in drivers. Fix devm_ioremap_resource() in the process. 2/ Rather than add yet another instance of "force cast away __iomem for non-io-memory" take the opportunity to introduce memremap() for this use case and fix up the current users that botch their handling of the __iomem annotation. 3/ Mandate that consumers of the pmem api handle the case when archs, or cpus within an arch are not able to make durability guarantees for writes to persistent memory. See pmem_ops in drivers/block/pmem.c 4/ Drop the persistent_flush() api as there are no users until the BLK driver is introduced, and even then it is not a "flush to persistence" it is an invalidation of a previous mmio aperture setting (io_flush_cache_range()). 5/ Add persistent_remap() to the pmem api for the arch to pick its desired memory type that corresponds to the assumptions of persistent_copy() and persistent_sync(). [1]: https://lists.01.org/pipermail/linux-nvdimm/2015-May/000929.html This boots and processes pmem writes on x86, cross-compile 0day results are still pending. --- Dan Williams (3): arch/*/asm/io.h: add ioremap_cache() to all architectures devm: fix ioremap_cache() usage arch: introduce memremap() Ross Zwisler (1): arch, x86: cache management apis for persistent memory arch/arc/include/asm/io.h | 1 arch/arm/include/asm/io.h | 2 + arch/arm64/include/asm/io.h | 2 + arch/arm64/kernel/efi.c | 4 + arch/arm64/kernel/smp_spin_table.c | 10 ++-- arch/avr32/include/asm/io.h | 1 arch/frv/include/asm/io.h | 6 ++ arch/m32r/include/asm/io.h | 1 arch/m68k/include/asm/io_mm.h | 7 +++ arch/m68k/include/asm/io_no.h | 5 ++ arch/metag/include/asm/io.h | 5 ++ arch/microblaze/include/asm/io.h | 1 arch/mn10300/include/asm/io.h | 1 arch/nios2/include/asm/io.h | 1 arch/s390/include/asm/io.h | 1 arch/sparc/include/asm/io_32.h | 1 arch/sparc/include/asm/io_64.h | 1 arch/tile/include/asm/io.h | 1 arch/x86/Kconfig | 1 arch/x86/include/asm/cacheflush.h | 24 +++++++++ arch/x86/include/asm/io.h | 7 +++ arch/x86/kernel/crash_dump_64.c | 6 +- arch/x86/kernel/kdebugfs.c | 8 +-- arch/x86/kernel/ksysfs.c | 28 +++++----- arch/x86/mm/ioremap.c | 10 +--- arch/xtensa/include/asm/io.h | 3 + drivers/acpi/apei/einj.c | 8 +-- drivers/acpi/apei/erst.c | 14 +++-- drivers/block/pmem.c | 62 +++++++++++++++++++++-- drivers/firmware/google/memconsole.c | 4 + include/asm-generic/io.h | 8 +++ include/asm-generic/iomap.h | 4 + include/linux/device.h | 5 ++ include/linux/io.h | 38 ++++++++++++++ include/linux/pmem.h | 93 ++++++++++++++++++++++++++++++++++ lib/Kconfig | 3 + lib/devres.c | 48 ++++++++---------- 37 files changed, 347 insertions(+), 78 deletions(-) create mode 100644 include/linux/pmem.h -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>