diff options
Diffstat (limited to 'drivers/dax')
-rw-r--r-- | drivers/dax/Kconfig | 27 | ||||
-rw-r--r-- | drivers/dax/Makefile | 2 | ||||
-rw-r--r-- | drivers/dax/bus.c | 2 | ||||
-rw-r--r-- | drivers/dax/bus.h | 2 | ||||
-rw-r--r-- | drivers/dax/dax-private.h | 2 | ||||
-rw-r--r-- | drivers/dax/hmem.c | 56 |
6 files changed, 83 insertions, 8 deletions
diff --git a/drivers/dax/Kconfig b/drivers/dax/Kconfig index f33c73e4af41..3b6c06f07326 100644 --- a/drivers/dax/Kconfig +++ b/drivers/dax/Kconfig @@ -32,19 +32,36 @@ config DEV_DAX_PMEM Say M if unsure +config DEV_DAX_HMEM + tristate "HMEM DAX: direct access to 'specific purpose' memory" + depends on EFI_SOFT_RESERVE + default DEV_DAX + help + EFI 2.8 platforms, and others, may advertise 'specific purpose' + memory. For example, a high bandwidth memory pool. The + indication from platform firmware is meant to reserve the + memory from typical usage by default. This driver creates + device-dax instances for these memory ranges, and that also + enables the possibility to assign them to the DEV_DAX_KMEM + driver to override the reservation and add them to kernel + "System RAM" pool. + + Say M if unsure. + config DEV_DAX_KMEM tristate "KMEM DAX: volatile-use of persistent memory" default DEV_DAX depends on DEV_DAX depends on MEMORY_HOTPLUG # for add_memory() and friends help - Support access to persistent memory as if it were RAM. This - allows easier use of persistent memory by unmodified - applications. + Support access to persistent, or other performance + differentiated memory as if it were System RAM. This allows + easier use of persistent memory by unmodified applications, or + adds core kernel memory services to heterogeneous memory types + (HMEM) marked "reserved" by platform firmware. To use this feature, a DAX device must be unbound from the - device_dax driver (PMEM DAX) and bound to this kmem driver - on each boot. + device_dax driver and bound to this kmem driver on each boot. Say N if unsure. diff --git a/drivers/dax/Makefile b/drivers/dax/Makefile index 81f7d54dadfb..80065b38b3c4 100644 --- a/drivers/dax/Makefile +++ b/drivers/dax/Makefile @@ -2,9 +2,11 @@ obj-$(CONFIG_DAX) += dax.o obj-$(CONFIG_DEV_DAX) += device_dax.o obj-$(CONFIG_DEV_DAX_KMEM) += kmem.o +obj-$(CONFIG_DEV_DAX_HMEM) += dax_hmem.o dax-y := super.o dax-y += bus.o device_dax-y := device.o +dax_hmem-y := hmem.o obj-y += pmem/ diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 8fafbeab510a..eccdda1f7b71 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -227,7 +227,7 @@ static void dax_region_unregister(void *region) struct dax_region *alloc_dax_region(struct device *parent, int region_id, struct resource *res, int target_node, unsigned int align, - unsigned long pfn_flags) + unsigned long long pfn_flags) { struct dax_region *dax_region; diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h index 8619e3299943..9e4eba67e8b9 100644 --- a/drivers/dax/bus.h +++ b/drivers/dax/bus.h @@ -11,7 +11,7 @@ struct dax_region; void dax_region_put(struct dax_region *dax_region); struct dax_region *alloc_dax_region(struct device *parent, int region_id, struct resource *res, int target_node, unsigned int align, - unsigned long flags); + unsigned long long flags); enum dev_dax_subsys { DEV_DAX_BUS, diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h index 6ccca3b890d6..3107ce80e809 100644 --- a/drivers/dax/dax-private.h +++ b/drivers/dax/dax-private.h @@ -32,7 +32,7 @@ struct dax_region { struct device *dev; unsigned int align; struct resource res; - unsigned long pfn_flags; + unsigned long long pfn_flags; }; /** diff --git a/drivers/dax/hmem.c b/drivers/dax/hmem.c new file mode 100644 index 000000000000..fe7214daf62e --- /dev/null +++ b/drivers/dax/hmem.c @@ -0,0 +1,56 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/platform_device.h> +#include <linux/memregion.h> +#include <linux/module.h> +#include <linux/pfn_t.h> +#include "bus.h" + +static int dax_hmem_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct dev_pagemap pgmap = { }; + struct dax_region *dax_region; + struct memregion_info *mri; + struct dev_dax *dev_dax; + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENOMEM; + + mri = dev->platform_data; + memcpy(&pgmap.res, res, sizeof(*res)); + + dax_region = alloc_dax_region(dev, pdev->id, res, mri->target_node, + PMD_SIZE, PFN_DEV|PFN_MAP); + if (!dax_region) + return -ENOMEM; + + dev_dax = devm_create_dev_dax(dax_region, 0, &pgmap); + if (IS_ERR(dev_dax)) + return PTR_ERR(dev_dax); + + /* child dev_dax instances now own the lifetime of the dax_region */ + dax_region_put(dax_region); + return 0; +} + +static int dax_hmem_remove(struct platform_device *pdev) +{ + /* devm handles teardown */ + return 0; +} + +static struct platform_driver dax_hmem_driver = { + .probe = dax_hmem_probe, + .remove = dax_hmem_remove, + .driver = { + .name = "hmem", + }, +}; + +module_platform_driver(dax_hmem_driver); + +MODULE_ALIAS("platform:hmem*"); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Intel Corporation"); |