[PATCH v3 2/8] memregion: Support fine grained invalidate by cpu_cache_invalidate_memregion()
From: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Date: 2025-08-20 10:30:59
Also in:
linux-acpi, linux-arch, linux-cxl, linux-mm
Subsystem:
compute express link (cxl), libnvdimm: non-volatile memory device subsystem, the rest, x86 architecture (32-bit and 64-bit), x86 mm · Maintainers:
Davidlohr Bueso, Jonathan Cameron, Dave Jiang, Alison Schofield, Vishal Verma, Dan Williams, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, Andy Lutomirski, Peter Zijlstra
From: Yicong Yang <yangyicong@hisilicon.com>
Extend cpu_cache_invalidate_memregion() to support invalidate certain range
of memory by introducing start and length parameters. Control of types of
invalidation is left for when usecases turn up. For now everything is
Clean and Invalidate.
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
v3: Rebase on top of previous patch that removed the IO_RESDESC_*
parameter.
---
arch/x86/mm/pat/set_memory.c | 2 +-
drivers/cxl/core/region.c | 5 ++++-
drivers/nvdimm/region.c | 2 +-
drivers/nvdimm/region_devs.c | 2 +-
include/linux/memregion.h | 7 +++++--
5 files changed, 12 insertions(+), 6 deletions(-)
diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
index 4019b17fb65e..292c7202faed 100644
--- a/arch/x86/mm/pat/set_memory.c
+++ b/arch/x86/mm/pat/set_memory.c@@ -368,7 +368,7 @@ bool cpu_cache_has_invalidate_memregion(void) } EXPORT_SYMBOL_NS_GPL(cpu_cache_has_invalidate_memregion, "DEVMEM"); -int cpu_cache_invalidate_memregion(void) +int cpu_cache_invalidate_memregion(phys_addr_t start, size_t len) { if (WARN_ON_ONCE(!cpu_cache_has_invalidate_memregion())) return -ENXIO;
diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index d7fa76810f82..410e41cef5d3 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c@@ -228,7 +228,10 @@ static int cxl_region_invalidate_memregion(struct cxl_region *cxlr) return -ENXIO; } - cpu_cache_invalidate_memregion(); + if (!cxlr->params.res) + return -ENXIO; + cpu_cache_invalidate_memregion(cxlr->params.res->start, + resource_size(cxlr->params.res)); return 0; }
diff --git a/drivers/nvdimm/region.c b/drivers/nvdimm/region.c
index c43506448edf..62535d200402 100644
--- a/drivers/nvdimm/region.c
+++ b/drivers/nvdimm/region.c@@ -110,7 +110,7 @@ static void nd_region_remove(struct device *dev) * here is ok. */ if (cpu_cache_has_invalidate_memregion()) - cpu_cache_invalidate_memregion(); + cpu_cache_invalidate_memregion(0, -1); } static int child_notify(struct device *dev, void *data)
diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c
index 3cdd93d40997..7c1d27c75b73 100644
--- a/drivers/nvdimm/region_devs.c
+++ b/drivers/nvdimm/region_devs.c@@ -90,7 +90,7 @@ static int nd_region_invalidate_memregion(struct nd_region *nd_region) } } - cpu_cache_invalidate_memregion(); + cpu_cache_invalidate_memregion(0, -1); out: for (i = 0; i < nd_region->ndr_mappings; i++) { struct nd_mapping *nd_mapping = &nd_region->mapping[i];
diff --git a/include/linux/memregion.h b/include/linux/memregion.h
index 945646bde825..428635562302 100644
--- a/include/linux/memregion.h
+++ b/include/linux/memregion.h@@ -27,6 +27,9 @@ static inline void memregion_free(int id) /** * cpu_cache_invalidate_memregion - drop any CPU cached data for * memregion + * @start: start physical address of the target memory region. + * @len: length of the target memory region. -1 for all the regions of + * the target type. * * Perform cache maintenance after a memory event / operation that * changes the contents of physical memory in a cache-incoherent manner.
@@ -45,7 +48,7 @@ static inline void memregion_free(int id) * the cache maintenance. */ #ifdef CONFIG_ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION -int cpu_cache_invalidate_memregion(void); +int cpu_cache_invalidate_memregion(phys_addr_t start, size_t len); bool cpu_cache_has_invalidate_memregion(void); #else static inline bool cpu_cache_has_invalidate_memregion(void)
@@ -53,7 +56,7 @@ static inline bool cpu_cache_has_invalidate_memregion(void) return false; } -static inline int cpu_cache_invalidate_memregion(void) +static inline int cpu_cache_invalidate_memregion(phys_addr_t start, size_t len) { WARN_ON_ONCE("CPU cache invalidation required"); return -ENXIO;
--
2.48.1