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authorDan Williams <dan.j.williams@intel.com>2020-10-13 16:49:28 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-10-13 18:38:28 -0700
commit5ccac54f3e124a49789c3773d5a351e87470cf12 (patch)
treeddee395823c58f32d4d95b525bc6dab2fd78cf72 /drivers/dax
parenta035b6bf863e5c42c2746de2a8ed6600140307e7 (diff)
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ACPI: HMAT: attach a device for each soft-reserved range
The hmem enabling in commit cf8741ac57ed ("ACPI: NUMA: HMAT: Register "soft reserved" memory as an "hmem" device") only registered ranges to the hmem driver for each soft-reservation that also appeared in the HMAT. While this is meant to encourage platform firmware to "do the right thing" and publish an HMAT, the corollary is that platforms that fail to publish an accurate HMAT will strand memory from Linux usage. Additionally, the "efi_fake_mem" kernel command line option enabling will strand memory by default without an HMAT. Arrange for "soft reserved" memory that goes unclaimed by HMAT entries to be published as raw resource ranges for the hmem driver to consume. Include a module parameter to disable either this fallback behavior, or the hmat enabling from creating hmem devices. The module parameter requires the hmem device enabling to have unique name in the module namespace: "device_hmem". The driver depends on the architecture providing phys_to_target_node() which is only x86 via numa_meminfo() and arm64 via a generic memblock implementation. [joao.m.martins@oracle.com: require NUMA_KEEP_MEMINFO for phys_to_target_node()] Link: https://lkml.kernel.org/r/aaae71a7-4846-f5cc-5acf-cf05fdb1f2dc@oracle.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Joao Martins <joao.m.martins@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Joao Martins <joao.m.martins@oracle.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Brice Goglin <Brice.Goglin@inria.fr> Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: David Airlie <airlied@linux.ie> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jason Gunthorpe <jgg@mellanox.com> Cc: Jia He <justin.he@arm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Wei Yang <richard.weiyang@linux.alibaba.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Hulk Robot <hulkci@huawei.com> Cc: Jason Yan <yanaijie@huawei.com> Cc: "Jérôme Glisse" <jglisse@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: kernel test robot <lkp@intel.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Link: https://lkml.kernel.org/r/159643098298.4062302.17587338161136144730.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/dax')
-rw-r--r--drivers/dax/Kconfig2
-rw-r--r--drivers/dax/hmem/Makefile3
-rw-r--r--drivers/dax/hmem/device.c35
3 files changed, 39 insertions, 1 deletions
diff --git a/drivers/dax/Kconfig b/drivers/dax/Kconfig
index a66dff78f298..567428e10b7b 100644
--- a/drivers/dax/Kconfig
+++ b/drivers/dax/Kconfig
@@ -35,6 +35,7 @@ config DEV_DAX_PMEM
config DEV_DAX_HMEM
tristate "HMEM DAX: direct access to 'specific purpose' memory"
depends on EFI_SOFT_RESERVE
+ select NUMA_KEEP_MEMINFO if (NUMA && X86)
default DEV_DAX
help
EFI 2.8 platforms, and others, may advertise 'specific purpose'
@@ -49,6 +50,7 @@ config DEV_DAX_HMEM
Say M if unsure.
config DEV_DAX_HMEM_DEVICES
+ depends on NUMA_KEEP_MEMINFO # for phys_to_target_node()
depends on DEV_DAX_HMEM && DAX=y
def_bool y
diff --git a/drivers/dax/hmem/Makefile b/drivers/dax/hmem/Makefile
index a9d353d0c9ed..57377b4c3d47 100644
--- a/drivers/dax/hmem/Makefile
+++ b/drivers/dax/hmem/Makefile
@@ -1,5 +1,6 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_DEV_DAX_HMEM) += dax_hmem.o
-obj-$(CONFIG_DEV_DAX_HMEM_DEVICES) += device.o
+obj-$(CONFIG_DEV_DAX_HMEM_DEVICES) += device_hmem.o
+device_hmem-y := device.o
dax_hmem-y := hmem.o
diff --git a/drivers/dax/hmem/device.c b/drivers/dax/hmem/device.c
index b9dd6b27745c..cb6401c9e9a4 100644
--- a/drivers/dax/hmem/device.c
+++ b/drivers/dax/hmem/device.c
@@ -5,6 +5,9 @@
#include <linux/dax.h>
#include <linux/mm.h>
+static bool nohmem;
+module_param_named(disable, nohmem, bool, 0444);
+
void hmem_register_device(int target_nid, struct resource *r)
{
/* define a clean / non-busy resource for the platform device */
@@ -17,6 +20,9 @@ void hmem_register_device(int target_nid, struct resource *r)
struct memregion_info info;
int rc, id;
+ if (nohmem)
+ return;
+
rc = region_intersects(res.start, resource_size(&res), IORESOURCE_MEM,
IORES_DESC_SOFT_RESERVED);
if (rc != REGION_INTERSECTS)
@@ -63,3 +69,32 @@ out_resource:
out_pdev:
memregion_free(id);
}
+
+static __init int hmem_register_one(struct resource *res, void *data)
+{
+ /*
+ * If the resource is not a top-level resource it was already
+ * assigned to a device by the HMAT parsing.
+ */
+ if (res->parent != &iomem_resource) {
+ pr_info("HMEM: skip %pr, already claimed\n", res);
+ return 0;
+ }
+
+ hmem_register_device(phys_to_target_node(res->start), res);
+
+ return 0;
+}
+
+static __init int hmem_init(void)
+{
+ walk_iomem_res_desc(IORES_DESC_SOFT_RESERVED,
+ IORESOURCE_MEM, 0, -1, NULL, hmem_register_one);
+ return 0;
+}
+
+/*
+ * As this is a fallback for address ranges unclaimed by the ACPI HMAT
+ * parsing it must be at an initcall level greater than hmat_init().
+ */
+late_initcall(hmem_init);