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* [PATCH v4 00/10] EFI Specific Purpose Memory Support
@ 2019-06-24 18:19 Dan Williams
  2019-06-24 18:19 ` [PATCH v4 01/10] acpi/numa: Establish a new drivers/acpi/numa/ directory Dan Williams
                   ` (9 more replies)
  0 siblings, 10 replies; 21+ messages in thread
From: Dan Williams @ 2019-06-24 18:19 UTC (permalink / raw)
  To: x86
  Cc: Dave Jiang, Jonathan Cameron, Keith Busch, kbuild test robot,
	Andy Shevchenko, Borislav Petkov, Vishal Verma, H. Peter Anvin,
	Thomas Gleixner, Dave Hansen, Matthew Wilcox, Ingo Molnar,
	Len Brown, Peter Zijlstra, Rafael J. Wysocki, Ard Biesheuvel,
	Andy Lutomirski, Darren Hart, tglx, linux-acpi, linux-nvdimm,
	linux-kernel

Changes since v3 [1]:
- Clarify in the changelog that the policy decision of how to treat
  specific-purpose memory is x86 only until other archs grow a
  translation to IORES_DESC_APPLICATION_RESERVED. The EFI spec does not
  mandate a behavior for the EFI_MEMORY_SP attribute so the decision is
  kept out of the core EFI implementation. (prompted by Ard)

- Merge the memregion ida into kernel/resource.c and provide a static
  inline wrappers around an exported  'struct ida memregion_ids'
  instance. (Willy)

- Fix a set of compile errors in the CONFIG_EFI_FAKE_MEMMAP=n case.
  (0day)

- Collect Dave's reviewed-by on the series.

[1]: https://lore.kernel.org/lkml/155993563277.3036719.17400338098057706494.stgit@dwillia2-desk3.amr.corp.intel.com/

---

Merge logistics: These patches touch core-efi, acpi, device-dax, and
x86. Given the regression risk is highest for the x86 changes it seems
tip.git is the best tree to host the series.

---

The EFI 2.8 Specification [2] introduces the EFI_MEMORY_SP ("specific
purpose") memory attribute. This attribute bit replaces the deprecated
ACPI HMAT "reservation hint" that was introduced in ACPI 6.2 and removed
in ACPI 6.3.

Given the increasing diversity of memory types that might be advertised
to the operating system, there is a need for platform firmware to hint
which memory ranges are free for the OS to use as general purpose memory
and which ranges are intended for application specific usage. For
example, an application with prior knowledge of the platform may expect
to be able to exclusively allocate a precious / limited pool of high
bandwidth memory. Alternatively, for the general purpose case, the
operating system may want to make the memory available on a best effort
basis as a unique numa-node with performance properties by the new
CONFIG_HMEM_REPORTING [3] facility.

In support of optionally allowing either application-exclusive and
core-kernel-mm managed access to differentiated memory, claim
EFI_MEMORY_SP ranges for exposure as device-dax instances by default.
Such instances can be directly owned / mapped by a
platform-topology-aware application. Alternatively, with the new kmem
facility [4], the administrator has the option to instead designate that
those memory ranges be hot-added to the core-kernel-mm as a unique
memory numa-node. In short, allow for the decision about what software
agent manages specific-purpose memory to be made at runtime.

The patches build on the new HMAT+HMEM_REPORTING facilities merged
for v5.2-rc1. The implementation is tested with qemu emulation of HMAT
[5] plus the efi_fake_mem facility for applying the EFI_MEMORY_SP
attribute.

[2]: https://uefi.org/sites/default/files/resources/UEFI_Spec_2_8_final.pdf
[3]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e1cf33aafb84
[4]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c221c0b0308f
[5]: http://patchwork.ozlabs.org/cover/1096737/

---

Dan Williams (10):
      acpi/numa: Establish a new drivers/acpi/numa/ directory
      acpi/numa/hmat: Skip publishing target info for nodes with no online memory
      efi: Enumerate EFI_MEMORY_SP
      x86, efi: Push EFI_MEMMAP check into leaf routines
      x86, efi: Reserve UEFI 2.8 Specific Purpose Memory for dax
      x86, efi: Add efi_fake_mem support for EFI_MEMORY_SP
      resource: Uplevel the pmem "region" ida to a global allocator
      device-dax: Add a driver for "hmem" devices
      acpi/numa/hmat: Register HMAT at device_initcall level
      acpi/numa/hmat: Register "specific purpose" memory as an "hmem" device


 arch/x86/Kconfig                    |   23 +++++
 arch/x86/boot/compressed/eboot.c    |    5 +
 arch/x86/boot/compressed/kaslr.c    |    3 -
 arch/x86/include/asm/e820/types.h   |    9 ++
 arch/x86/include/asm/efi.h          |   34 ++++++++
 arch/x86/kernel/e820.c              |   12 ++-
 arch/x86/kernel/setup.c             |   21 +++--
 arch/x86/platform/efi/efi.c         |   40 +++++++++
 arch/x86/platform/efi/quirks.c      |    3 +
 drivers/acpi/Kconfig                |    9 --
 drivers/acpi/Makefile               |    3 -
 drivers/acpi/hmat/Makefile          |    2 
 drivers/acpi/numa/Kconfig           |    8 ++
 drivers/acpi/numa/Makefile          |    3 +
 drivers/acpi/numa/hmat.c            |  148 +++++++++++++++++++++++++++++++----
 drivers/acpi/numa/srat.c            |    0 
 drivers/dax/Kconfig                 |   27 +++++-
 drivers/dax/Makefile                |    2 
 drivers/dax/hmem.c                  |   57 +++++++++++++
 drivers/firmware/efi/Makefile       |    5 +
 drivers/firmware/efi/efi.c          |    5 +
 drivers/firmware/efi/esrt.c         |    3 +
 drivers/firmware/efi/fake_mem.c     |   26 +++---
 drivers/firmware/efi/fake_mem.h     |   10 ++
 drivers/firmware/efi/x86-fake_mem.c |   69 ++++++++++++++++
 drivers/nvdimm/Kconfig              |    1 
 drivers/nvdimm/core.c               |    1 
 drivers/nvdimm/nd-core.h            |    1 
 drivers/nvdimm/region_devs.c        |   12 +--
 include/linux/efi.h                 |    3 -
 include/linux/ioport.h              |   32 ++++++++
 kernel/resource.c                   |    6 +
 lib/Kconfig                         |    3 +
 33 files changed, 504 insertions(+), 82 deletions(-)
 delete mode 100644 drivers/acpi/hmat/Makefile
 rename drivers/acpi/{hmat/Kconfig => numa/Kconfig} (70%)
 create mode 100644 drivers/acpi/numa/Makefile
 rename drivers/acpi/{hmat/hmat.c => numa/hmat.c} (81%)
 rename drivers/acpi/{numa.c => numa/srat.c} (100%)
 create mode 100644 drivers/dax/hmem.c
 create mode 100644 drivers/firmware/efi/fake_mem.h
 create mode 100644 drivers/firmware/efi/x86-fake_mem.c

^ permalink raw reply	[flat|nested] 21+ messages in thread

* [PATCH v4 01/10] acpi/numa: Establish a new drivers/acpi/numa/ directory
  2019-06-24 18:19 [PATCH v4 00/10] EFI Specific Purpose Memory Support Dan Williams
@ 2019-06-24 18:19 ` Dan Williams
  2019-06-25 14:59   ` Jonathan Cameron
  2019-07-03 11:09   ` Rafael J. Wysocki
  2019-06-24 18:19 ` [PATCH v4 02/10] acpi/numa/hmat: Skip publishing target info for nodes with no online memory Dan Williams
                   ` (8 subsequent siblings)
  9 siblings, 2 replies; 21+ messages in thread
From: Dan Williams @ 2019-06-24 18:19 UTC (permalink / raw)
  To: x86
  Cc: Len Brown, Keith Busch, Rafael J. Wysocki, Dave Hansen, peterz,
	vishal.l.verma, ard.biesheuvel, tglx, linux-acpi, linux-nvdimm,
	linux-kernel

Currently hmat.c lives under an "hmat" directory which does not enhance
the description of the file. The initial motivation for giving hmat.c
its own directory was to delineate it as mm functionality in contrast to
ACPI device driver functionality.

As ACPI continues to play an increasing role in conveying
memory location and performance topology information to the OS take the
opportunity to co-locate these NUMA relevant tables in a combined
directory.

numa.c is renamed to srat.c and moved to drivers/acpi/numa/ along with
hmat.c.

Cc: Len Brown <lenb@kernel.org>
Cc: Keith Busch <keith.busch@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 drivers/acpi/Kconfig       |    9 +--------
 drivers/acpi/Makefile      |    3 +--
 drivers/acpi/hmat/Makefile |    2 --
 drivers/acpi/numa/Kconfig  |    7 ++++++-
 drivers/acpi/numa/Makefile |    3 +++
 drivers/acpi/numa/hmat.c   |    0 
 drivers/acpi/numa/srat.c   |    0 
 7 files changed, 11 insertions(+), 13 deletions(-)
 delete mode 100644 drivers/acpi/hmat/Makefile
 rename drivers/acpi/{hmat/Kconfig => numa/Kconfig} (72%)
 create mode 100644 drivers/acpi/numa/Makefile
 rename drivers/acpi/{hmat/hmat.c => numa/hmat.c} (100%)
 rename drivers/acpi/{numa.c => numa/srat.c} (100%)

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 283ee94224c6..82c4a31c8701 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -321,12 +321,6 @@ config ACPI_THERMAL
 	  To compile this driver as a module, choose M here:
 	  the module will be called thermal.
 
-config ACPI_NUMA
-	bool "NUMA support"
-	depends on NUMA
-	depends on (X86 || IA64 || ARM64)
-	default y if IA64_GENERIC || IA64_SGI_SN2 || ARM64
-
 config ACPI_CUSTOM_DSDT_FILE
 	string "Custom DSDT Table file to include"
 	default ""
@@ -475,8 +469,7 @@ config ACPI_REDUCED_HARDWARE_ONLY
 	  If you are unsure what to do, do not enable this option.
 
 source "drivers/acpi/nfit/Kconfig"
-source "drivers/acpi/hmat/Kconfig"
-
+source "drivers/acpi/numa/Kconfig"
 source "drivers/acpi/apei/Kconfig"
 source "drivers/acpi/dptf/Kconfig"
 
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 5d361e4e3405..f08a661274e8 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -55,7 +55,6 @@ acpi-$(CONFIG_X86)		+= acpi_cmos_rtc.o
 acpi-$(CONFIG_X86)		+= x86/apple.o
 acpi-$(CONFIG_X86)		+= x86/utils.o
 acpi-$(CONFIG_DEBUG_FS)		+= debugfs.o
-acpi-$(CONFIG_ACPI_NUMA)	+= numa.o
 acpi-$(CONFIG_ACPI_PROCFS_POWER) += cm_sbs.o
 acpi-y				+= acpi_lpat.o
 acpi-$(CONFIG_ACPI_LPIT)	+= acpi_lpit.o
@@ -80,7 +79,7 @@ obj-$(CONFIG_ACPI_PROCESSOR)	+= processor.o
 obj-$(CONFIG_ACPI)		+= container.o
 obj-$(CONFIG_ACPI_THERMAL)	+= thermal.o
 obj-$(CONFIG_ACPI_NFIT)		+= nfit/
-obj-$(CONFIG_ACPI_HMAT)		+= hmat/
+obj-$(CONFIG_ACPI_NUMA)		+= numa/
 obj-$(CONFIG_ACPI)		+= acpi_memhotplug.o
 obj-$(CONFIG_ACPI_HOTPLUG_IOAPIC) += ioapic.o
 obj-$(CONFIG_ACPI_BATTERY)	+= battery.o
diff --git a/drivers/acpi/hmat/Makefile b/drivers/acpi/hmat/Makefile
deleted file mode 100644
index 1c20ef36a385..000000000000
--- a/drivers/acpi/hmat/Makefile
+++ /dev/null
@@ -1,2 +0,0 @@
-# SPDX-License-Identifier: GPL-2.0-only
-obj-$(CONFIG_ACPI_HMAT) := hmat.o
diff --git a/drivers/acpi/hmat/Kconfig b/drivers/acpi/numa/Kconfig
similarity index 72%
rename from drivers/acpi/hmat/Kconfig
rename to drivers/acpi/numa/Kconfig
index 95a29964dbea..d14582387ed0 100644
--- a/drivers/acpi/hmat/Kconfig
+++ b/drivers/acpi/numa/Kconfig
@@ -1,4 +1,9 @@
-# SPDX-License-Identifier: GPL-2.0
+config ACPI_NUMA
+	bool "NUMA support"
+	depends on NUMA
+	depends on (X86 || IA64 || ARM64)
+	default y if IA64_GENERIC || IA64_SGI_SN2 || ARM64
+
 config ACPI_HMAT
 	bool "ACPI Heterogeneous Memory Attribute Table Support"
 	depends on ACPI_NUMA
diff --git a/drivers/acpi/numa/Makefile b/drivers/acpi/numa/Makefile
new file mode 100644
index 000000000000..517a6c689a94
--- /dev/null
+++ b/drivers/acpi/numa/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_ACPI_NUMA) += srat.o
+obj-$(CONFIG_ACPI_HMAT) += hmat.o
diff --git a/drivers/acpi/hmat/hmat.c b/drivers/acpi/numa/hmat.c
similarity index 100%
rename from drivers/acpi/hmat/hmat.c
rename to drivers/acpi/numa/hmat.c
diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa/srat.c
similarity index 100%
rename from drivers/acpi/numa.c
rename to drivers/acpi/numa/srat.c


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v4 02/10] acpi/numa/hmat: Skip publishing target info for nodes with no online memory
  2019-06-24 18:19 [PATCH v4 00/10] EFI Specific Purpose Memory Support Dan Williams
  2019-06-24 18:19 ` [PATCH v4 01/10] acpi/numa: Establish a new drivers/acpi/numa/ directory Dan Williams
@ 2019-06-24 18:19 ` Dan Williams
  2019-07-03 11:10   ` Rafael J. Wysocki
  2019-06-24 18:19 ` [PATCH v4 03/10] efi: Enumerate EFI_MEMORY_SP Dan Williams
                   ` (7 subsequent siblings)
  9 siblings, 1 reply; 21+ messages in thread
From: Dan Williams @ 2019-06-24 18:19 UTC (permalink / raw)
  To: x86
  Cc: Dave Hansen, peterz, vishal.l.verma, ard.biesheuvel, tglx,
	linux-acpi, linux-nvdimm, linux-kernel

There are multiple scenarios where the HMAT may contain information
about proximity domains that are not currently online. Rather than fail
to report any HMAT data just elide those offline domains.

If and when those domains are later onlined they can be added to the
HMEM reporting at that point.

This was found while testing EFI_MEMORY_SP support which reserves
"specific purpose" memory from the general allocation pool. If that
reservation results in an empty numa-node then the node is not marked
online leading a spurious:

    "acpi/hmat: Ignoring HMAT: Invalid table"

...result for HMAT parsing.

Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 drivers/acpi/numa/hmat.c |   14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c
index 96b7d39a97c6..2c220cb7b620 100644
--- a/drivers/acpi/numa/hmat.c
+++ b/drivers/acpi/numa/hmat.c
@@ -96,9 +96,6 @@ static __init void alloc_memory_target(unsigned int mem_pxm)
 {
 	struct memory_target *target;
 
-	if (pxm_to_node(mem_pxm) == NUMA_NO_NODE)
-		return;
-
 	target = find_mem_target(mem_pxm);
 	if (target)
 		return;
@@ -588,6 +585,17 @@ static __init void hmat_register_targets(void)
 	struct memory_target *target;
 
 	list_for_each_entry(target, &targets, node) {
+		int nid = pxm_to_node(target->memory_pxm);
+
+		/*
+		 * Skip offline nodes. This can happen when memory
+		 * marked EFI_MEMORY_SP, "specific purpose", is applied
+		 * to all the memory in a promixity domain leading to
+		 * the node being marked offline / unplugged, or if
+		 * memory-only "hotplug" node is offline.
+		 */
+		if (nid == NUMA_NO_NODE || !node_online(nid))
+			continue;
 		hmat_register_target_initiators(target);
 		hmat_register_target_perf(target);
 	}


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v4 03/10] efi: Enumerate EFI_MEMORY_SP
  2019-06-24 18:19 [PATCH v4 00/10] EFI Specific Purpose Memory Support Dan Williams
  2019-06-24 18:19 ` [PATCH v4 01/10] acpi/numa: Establish a new drivers/acpi/numa/ directory Dan Williams
  2019-06-24 18:19 ` [PATCH v4 02/10] acpi/numa/hmat: Skip publishing target info for nodes with no online memory Dan Williams
@ 2019-06-24 18:19 ` Dan Williams
  2019-06-24 18:19 ` [PATCH v4 04/10] x86, efi: Push EFI_MEMMAP check into leaf routines Dan Williams
                   ` (6 subsequent siblings)
  9 siblings, 0 replies; 21+ messages in thread
From: Dan Williams @ 2019-06-24 18:19 UTC (permalink / raw)
  To: x86
  Cc: Ard Biesheuvel, Dave Hansen, peterz, vishal.l.verma, tglx,
	linux-acpi, linux-nvdimm, linux-kernel

UEFI 2.8 defines an EFI_MEMORY_SP attribute bit to augment the
interpretation of the EFI Memory Types as "reserved for a specific
purpose". The intent of this bit is to allow the OS to identify precious
or scarce memory resources and optionally manage it separately from
EfiConventionalMemory. As defined older OSes that do not know about this
attribute are permitted to ignore it and the memory will be handled
according to the OS default policy for the given memory type.

In other words, this "specific purpose" hint is deliberately weaker than
EfiReservedMemoryType in that the system continues to operate if the OS
takes no action on the attribute. The risk of taking no action is
potentially unwanted / unmovable kernel allocations from the designated
resource that prevent the full realization of the "specific purpose".
For example, consider a system with a high-bandwidth memory pool. Older
kernels are permitted to boot and consume that memory as conventional
"System-RAM" newer kernels may arrange for that memory to be set aside
by the system administrator for a dedicated high-bandwidth memory aware
application to consume.

Specifically, this mechanism allows for the elimination of scenarios
where platform firmware tries to game OS policy by lying about ACPI SLIT
values, i.e. claiming that a precious memory resource has a high
distance to trigger the OS to avoid it by default.

Implement simple detection of the bit for EFI memory table dumps and
save the kernel policy for a follow-on change.

Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 drivers/firmware/efi/efi.c |    5 +++--
 include/linux/efi.h        |    1 +
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 55b77c576c42..81db09485881 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -848,15 +848,16 @@ char * __init efi_md_typeattr_format(char *buf, size_t size,
 	if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
 		     EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
 		     EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
-		     EFI_MEMORY_NV |
+		     EFI_MEMORY_NV | EFI_MEMORY_SP |
 		     EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
 		snprintf(pos, size, "|attr=0x%016llx]",
 			 (unsigned long long)attr);
 	else
 		snprintf(pos, size,
-			 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
+			 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
 			 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
 			 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
+			 attr & EFI_MEMORY_SP      ? "SP"  : "",
 			 attr & EFI_MEMORY_NV      ? "NV"  : "",
 			 attr & EFI_MEMORY_XP      ? "XP"  : "",
 			 attr & EFI_MEMORY_RP      ? "RP"  : "",
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 6ebc2098cfe1..91368f5ce114 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -112,6 +112,7 @@ typedef	struct {
 #define EFI_MEMORY_MORE_RELIABLE \
 				((u64)0x0000000000010000ULL)	/* higher reliability */
 #define EFI_MEMORY_RO		((u64)0x0000000000020000ULL)	/* read-only */
+#define EFI_MEMORY_SP		((u64)0x0000000000040000ULL)	/* special purpose */
 #define EFI_MEMORY_RUNTIME	((u64)0x8000000000000000ULL)	/* range requires runtime mapping */
 #define EFI_MEMORY_DESCRIPTOR_VERSION	1
 


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v4 04/10] x86, efi: Push EFI_MEMMAP check into leaf routines
  2019-06-24 18:19 [PATCH v4 00/10] EFI Specific Purpose Memory Support Dan Williams
                   ` (2 preceding siblings ...)
  2019-06-24 18:19 ` [PATCH v4 03/10] efi: Enumerate EFI_MEMORY_SP Dan Williams
@ 2019-06-24 18:19 ` Dan Williams
  2019-06-24 18:19 ` [PATCH v4 05/10] x86, efi: Reserve UEFI 2.8 Specific Purpose Memory for dax Dan Williams
                   ` (5 subsequent siblings)
  9 siblings, 0 replies; 21+ messages in thread
From: Dan Williams @ 2019-06-24 18:19 UTC (permalink / raw)
  To: x86
  Cc: Ingo Molnar, H. Peter Anvin, Andy Lutomirski, Thomas Gleixner,
	Peter Zijlstra, Dave Hansen, vishal.l.verma, ard.biesheuvel,
	tglx, linux-acpi, linux-nvdimm, linux-kernel

In preparation for adding another EFI_MEMMAP dependent call that needs
to occur before e820__memblock_setup() fixup the existing efi calls to
check for EFI_MEMMAP internally. This is cleaner than checking
EFI_MEMMAP multiple times in setup_arch().

Cc: <x86@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 arch/x86/include/asm/efi.h      |    9 ++++++++-
 arch/x86/kernel/setup.c         |   19 +++++++++----------
 arch/x86/platform/efi/efi.c     |    3 +++
 arch/x86/platform/efi/quirks.c  |    3 +++
 drivers/firmware/efi/esrt.c     |    3 +++
 drivers/firmware/efi/fake_mem.c |    2 +-
 include/linux/efi.h             |    2 --
 7 files changed, 27 insertions(+), 14 deletions(-)

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 606a4b6a9812..7d52378e376a 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -140,7 +140,6 @@ extern void efi_delete_dummy_variable(void);
 extern void efi_switch_mm(struct mm_struct *mm);
 extern void efi_recover_from_page_fault(unsigned long phys_addr);
 extern void efi_free_boot_services(void);
-extern void efi_reserve_boot_services(void);
 
 struct efi_setup_data {
 	u64 fw_vendor;
@@ -243,12 +242,20 @@ static inline bool efi_is_64bit(void)
 
 extern bool efi_reboot_required(void);
 
+extern void efi_find_mirror(void);
+extern void efi_reserve_boot_services(void);
 #else
 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
 static inline bool efi_reboot_required(void)
 {
 	return false;
 }
+static inline void efi_find_mirror(void)
+{
+}
+static inline void efi_reserve_boot_services(void)
+{
+}
 #endif /* CONFIG_EFI */
 
 #endif /* _ASM_X86_EFI_H */
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 08a5f4a131f5..b68fd57a8d26 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -1103,21 +1103,20 @@ void __init setup_arch(char **cmdline_p)
 	cleanup_highmap();
 
 	memblock_set_current_limit(ISA_END_ADDRESS);
+
 	e820__memblock_setup();
 
 	reserve_bios_regions();
 
-	if (efi_enabled(EFI_MEMMAP)) {
-		efi_fake_memmap();
-		efi_find_mirror();
-		efi_esrt_init();
+	efi_fake_memmap();
+	efi_find_mirror();
+	efi_esrt_init();
 
-		/*
-		 * The EFI specification says that boot service code won't be
-		 * called after ExitBootServices(). This is, in fact, a lie.
-		 */
-		efi_reserve_boot_services();
-	}
+	/*
+	 * The EFI specification says that boot service code won't be
+	 * called after ExitBootServices(). This is, in fact, a lie.
+	 */
+	efi_reserve_boot_services();
 
 	/* preallocate 4k for mptable mpc */
 	e820__memblock_alloc_reserved_mpc_new();
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index e1cb01a22fa8..4e8458b1ca30 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -103,6 +103,9 @@ void __init efi_find_mirror(void)
 	efi_memory_desc_t *md;
 	u64 mirror_size = 0, total_size = 0;
 
+	if (!efi_enabled(EFI_MEMMAP))
+		return;
+
 	for_each_efi_memory_desc(md) {
 		unsigned long long start = md->phys_addr;
 		unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c
index feb77777c8b8..50f7303da7be 100644
--- a/arch/x86/platform/efi/quirks.c
+++ b/arch/x86/platform/efi/quirks.c
@@ -320,6 +320,9 @@ void __init efi_reserve_boot_services(void)
 {
 	efi_memory_desc_t *md;
 
+	if (!efi_enabled(EFI_MEMMAP))
+		return;
+
 	for_each_efi_memory_desc(md) {
 		u64 start = md->phys_addr;
 		u64 size = md->num_pages << EFI_PAGE_SHIFT;
diff --git a/drivers/firmware/efi/esrt.c b/drivers/firmware/efi/esrt.c
index d6dd5f503fa2..2762e0662bf4 100644
--- a/drivers/firmware/efi/esrt.c
+++ b/drivers/firmware/efi/esrt.c
@@ -246,6 +246,9 @@ void __init efi_esrt_init(void)
 	int rc;
 	phys_addr_t end;
 
+	if (!efi_enabled(EFI_MEMMAP))
+		return;
+
 	pr_debug("esrt-init: loading.\n");
 	if (!esrt_table_exists())
 		return;
diff --git a/drivers/firmware/efi/fake_mem.c b/drivers/firmware/efi/fake_mem.c
index 9501edc0fcfb..526b45331d96 100644
--- a/drivers/firmware/efi/fake_mem.c
+++ b/drivers/firmware/efi/fake_mem.c
@@ -44,7 +44,7 @@ void __init efi_fake_memmap(void)
 	void *new_memmap;
 	int i;
 
-	if (!nr_fake_mem)
+	if (!efi_enabled(EFI_MEMMAP) || !nr_fake_mem)
 		return;
 
 	/* count up the number of EFI memory descriptor */
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 91368f5ce114..ea6ce3ef71f5 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -1042,9 +1042,7 @@ extern void efi_enter_virtual_mode (void);	/* switch EFI to virtual mode, if pos
 extern efi_status_t efi_query_variable_store(u32 attributes,
 					     unsigned long size,
 					     bool nonblocking);
-extern void efi_find_mirror(void);
 #else
-
 static inline efi_status_t efi_query_variable_store(u32 attributes,
 						    unsigned long size,
 						    bool nonblocking)


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v4 05/10] x86, efi: Reserve UEFI 2.8 Specific Purpose Memory for dax
  2019-06-24 18:19 [PATCH v4 00/10] EFI Specific Purpose Memory Support Dan Williams
                   ` (3 preceding siblings ...)
  2019-06-24 18:19 ` [PATCH v4 04/10] x86, efi: Push EFI_MEMMAP check into leaf routines Dan Williams
@ 2019-06-24 18:19 ` Dan Williams
  2019-06-25 15:26   ` Jonathan Cameron
  2019-06-24 18:20 ` [PATCH v4 06/10] x86, efi: Add efi_fake_mem support for EFI_MEMORY_SP Dan Williams
                   ` (4 subsequent siblings)
  9 siblings, 1 reply; 21+ messages in thread
From: Dan Williams @ 2019-06-24 18:19 UTC (permalink / raw)
  To: x86
  Cc: Borislav Petkov, Ingo Molnar, H. Peter Anvin, Darren Hart,
	Andy Shevchenko, Andy Lutomirski, Peter Zijlstra,
	Thomas Gleixner, Ard Biesheuvel, kbuild test robot, Dave Hansen,
	vishal.l.verma, tglx, linux-acpi, linux-nvdimm, linux-kernel

UEFI 2.8 defines an EFI_MEMORY_SP attribute bit to augment the
interpretation of the EFI Memory Types as "reserved for a specific
purpose".

The proposed Linux behavior for specific purpose memory is that it is
reserved for direct-access (device-dax) by default and not available for
any kernel usage, not even as an OOM fallback.  Later, through udev
scripts or another init mechanism, these device-dax claimed ranges can
be reconfigured and hot-added to the available System-RAM with a unique
node identifier.

This patch introduces 2 new concepts at once given the entanglement
between early boot enumeration relative to memory that can optionally be
reserved from the kernel page allocator by default. The new concepts
are:

- E820_TYPE_APPLICATION_RESERVED: Upon detecting the EFI_MEMORY_SP
  attribute on EFI_CONVENTIONAL memory, update the E820 map with this
  new type. Only perform this classification if the
  CONFIG_EFI_SPECIFIC_DAX=y policy is enabled, otherwise treat it as
  typical ram.

- IORES_DESC_APPLICATION_RESERVED: Add a new I/O resource descriptor for
  a device driver to search iomem resources for application specific
  memory. Teach the iomem code to identify such ranges as "Application
  Reserved".

A follow-on change integrates parsing of the ACPI HMAT to identify the
node and sub-range boundaries of EFI_MEMORY_SP designated memory. For
now, just identify and reserve memory of this type.

For now this translation of EFI_CONVENTIONAL + EFI_MEMORY_SP is
x86/E820-only, but other archs could choose to publish
IORES_DESC_APPLICATION_RESERVED resources from their platform-firmware
memory map handlers.

Cc: <x86@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Andy Shevchenko <andy@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reported-by: kbuild test robot <lkp@intel.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 arch/x86/Kconfig                  |   23 +++++++++++++++++++++++
 arch/x86/boot/compressed/eboot.c  |    5 ++++-
 arch/x86/boot/compressed/kaslr.c  |    3 ++-
 arch/x86/include/asm/e820/types.h |    9 +++++++++
 arch/x86/include/asm/efi.h        |   17 +++++++++++++++++
 arch/x86/kernel/e820.c            |   12 ++++++++++--
 arch/x86/kernel/setup.c           |    1 +
 arch/x86/platform/efi/efi.c       |   37 +++++++++++++++++++++++++++++++++----
 include/linux/ioport.h            |    1 +
 9 files changed, 100 insertions(+), 8 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 2bbbd4d1ba31..d8d3b4e87ac1 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1955,6 +1955,29 @@ config EFI_MIXED
 
 	   If unsure, say N.
 
+config EFI_APPLICATION_RESERVED
+	bool "Reserve EFI Specific Purpose Memory"
+	depends on ACPI_HMAT
+	default ACPI_HMAT
+	depends on EFI
+	---help---
+	  On systems that have mixed performance classes of memory EFI
+	  may indicate specific purpose memory with an attribute (See
+	  EFI_MEMORY_SP in UEFI 2.8). A memory range tagged with this
+	  attribute may have unique performance characteristics compared
+	  to the system's general purpose "System RAM" pool. On the
+	  expectation that such memory has application specific usage,
+	  and its base EFI memory type is "conventional" answer Y to
+	  arrange for the kernel to reserve it as an "Application
+	  Reserved" resource, and set aside for direct-access
+	  (device-dax) by default. The memory range can later be
+	  optionally assigned to the page allocator by system
+	  administrator policy via the device-dax kmem facility. Say N
+	  to have the kernel treat this memory as "System RAM" by
+	  default.
+
+	  If unsure, say Y.
+
 config SECCOMP
 	def_bool y
 	prompt "Enable seccomp to safely compute untrusted bytecode"
diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
index 544ac4fafd11..a6c96eb6e633 100644
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -560,7 +560,10 @@ setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_s
 		case EFI_BOOT_SERVICES_CODE:
 		case EFI_BOOT_SERVICES_DATA:
 		case EFI_CONVENTIONAL_MEMORY:
-			e820_type = E820_TYPE_RAM;
+			if (is_efi_application_reserved(d))
+				e820_type = E820_TYPE_APPLICATION_RESERVED;
+			else
+				e820_type = E820_TYPE_RAM;
 			break;
 
 		case EFI_ACPI_MEMORY_NVS:
diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
index 2e53c056ba20..e8306f452182 100644
--- a/arch/x86/boot/compressed/kaslr.c
+++ b/arch/x86/boot/compressed/kaslr.c
@@ -757,7 +757,8 @@ process_efi_entries(unsigned long minimum, unsigned long image_size)
 		 *
 		 * Only EFI_CONVENTIONAL_MEMORY is guaranteed to be free.
 		 */
-		if (md->type != EFI_CONVENTIONAL_MEMORY)
+		if (md->type != EFI_CONVENTIONAL_MEMORY
+				|| is_efi_application_reserved(md))
 			continue;
 
 		if (efi_mirror_found &&
diff --git a/arch/x86/include/asm/e820/types.h b/arch/x86/include/asm/e820/types.h
index c3aa4b5e49e2..41193c116a1f 100644
--- a/arch/x86/include/asm/e820/types.h
+++ b/arch/x86/include/asm/e820/types.h
@@ -28,6 +28,15 @@ enum e820_type {
 	 */
 	E820_TYPE_PRAM		= 12,
 
+	/*
+	 * Special-purpose / application-specific memory is indicated to
+	 * the system via the EFI_MEMORY_SP attribute. Define an e820
+	 * translation of this memory type for the purpose of
+	 * reserving this range and marking it with the
+	 * IORES_DESC_APPLICATION_RESERVED designation.
+	 */
+	E820_TYPE_APPLICATION_RESERVED	= 0xefffffff,
+
 	/*
 	 * Reserved RAM used by the kernel itself if
 	 * CONFIG_INTEL_TXT=y is enabled, memory of this type
diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 7d52378e376a..4f80254e0541 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -141,6 +141,19 @@ extern void efi_switch_mm(struct mm_struct *mm);
 extern void efi_recover_from_page_fault(unsigned long phys_addr);
 extern void efi_free_boot_services(void);
 
+#ifdef CONFIG_EFI_APPLICATION_RESERVED
+static inline bool is_efi_application_reserved(efi_memory_desc_t *md)
+{
+	return md->type == EFI_CONVENTIONAL_MEMORY
+		&& (md->attribute & EFI_MEMORY_SP);
+}
+#else
+static inline bool is_efi_application_reserved(efi_memory_desc_t *md)
+{
+	return false;
+}
+#endif
+
 struct efi_setup_data {
 	u64 fw_vendor;
 	u64 runtime;
@@ -244,6 +257,7 @@ extern bool efi_reboot_required(void);
 
 extern void efi_find_mirror(void);
 extern void efi_reserve_boot_services(void);
+extern void __init efi_find_application_reserved(void);
 #else
 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
 static inline bool efi_reboot_required(void)
@@ -256,6 +270,9 @@ static inline void efi_find_mirror(void)
 static inline void efi_reserve_boot_services(void)
 {
 }
+static inline void __init efi_find_application_reserved(void)
+{
+}
 #endif /* CONFIG_EFI */
 
 #endif /* _ASM_X86_EFI_H */
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 8f32e705a980..c5b91c2d0661 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -189,6 +189,7 @@ static void __init e820_print_type(enum e820_type type)
 	switch (type) {
 	case E820_TYPE_RAM:		/* Fall through: */
 	case E820_TYPE_RESERVED_KERN:	pr_cont("usable");			break;
+	case E820_TYPE_APPLICATION_RESERVED: pr_cont("application reserved");	break;
 	case E820_TYPE_RESERVED:	pr_cont("reserved");			break;
 	case E820_TYPE_ACPI:		pr_cont("ACPI data");			break;
 	case E820_TYPE_NVS:		pr_cont("ACPI NVS");			break;
@@ -1036,6 +1037,7 @@ static const char *__init e820_type_to_string(struct e820_entry *entry)
 	case E820_TYPE_UNUSABLE:	return "Unusable memory";
 	case E820_TYPE_PRAM:		return "Persistent Memory (legacy)";
 	case E820_TYPE_PMEM:		return "Persistent Memory";
+	case E820_TYPE_APPLICATION_RESERVED: return "Application Reserved";
 	case E820_TYPE_RESERVED:	return "Reserved";
 	default:			return "Unknown E820 type";
 	}
@@ -1051,6 +1053,7 @@ static unsigned long __init e820_type_to_iomem_type(struct e820_entry *entry)
 	case E820_TYPE_UNUSABLE:	/* Fall-through: */
 	case E820_TYPE_PRAM:		/* Fall-through: */
 	case E820_TYPE_PMEM:		/* Fall-through: */
+	case E820_TYPE_APPLICATION_RESERVED: /* Fall-through: */
 	case E820_TYPE_RESERVED:	/* Fall-through: */
 	default:			return IORESOURCE_MEM;
 	}
@@ -1063,6 +1066,7 @@ static unsigned long __init e820_type_to_iores_desc(struct e820_entry *entry)
 	case E820_TYPE_NVS:		return IORES_DESC_ACPI_NV_STORAGE;
 	case E820_TYPE_PMEM:		return IORES_DESC_PERSISTENT_MEMORY;
 	case E820_TYPE_PRAM:		return IORES_DESC_PERSISTENT_MEMORY_LEGACY;
+	case E820_TYPE_APPLICATION_RESERVED: return IORES_DESC_APPLICATION_RESERVED;
 	case E820_TYPE_RESERVED_KERN:	/* Fall-through: */
 	case E820_TYPE_RAM:		/* Fall-through: */
 	case E820_TYPE_UNUSABLE:	/* Fall-through: */
@@ -1078,13 +1082,14 @@ static bool __init do_mark_busy(enum e820_type type, struct resource *res)
 		return true;
 
 	/*
-	 * Treat persistent memory like device memory, i.e. reserve it
-	 * for exclusive use of a driver
+	 * Treat persistent memory and other special memory ranges like
+	 * device memory, i.e. reserve it for exclusive use of a driver
 	 */
 	switch (type) {
 	case E820_TYPE_RESERVED:
 	case E820_TYPE_PRAM:
 	case E820_TYPE_PMEM:
+	case E820_TYPE_APPLICATION_RESERVED:
 		return false;
 	case E820_TYPE_RESERVED_KERN:
 	case E820_TYPE_RAM:
@@ -1285,6 +1290,9 @@ void __init e820__memblock_setup(void)
 		if (end != (resource_size_t)end)
 			continue;
 
+		if (entry->type == E820_TYPE_APPLICATION_RESERVED)
+			memblock_reserve(entry->addr, entry->size);
+
 		if (entry->type != E820_TYPE_RAM && entry->type != E820_TYPE_RESERVED_KERN)
 			continue;
 
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index b68fd57a8d26..3b9001b7c951 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -1104,6 +1104,7 @@ void __init setup_arch(char **cmdline_p)
 
 	memblock_set_current_limit(ISA_END_ADDRESS);
 
+	efi_find_application_reserved();
 	e820__memblock_setup();
 
 	reserve_bios_regions();
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index 4e8458b1ca30..4b4a9eb6d2c9 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -126,10 +126,18 @@ void __init efi_find_mirror(void)
  * more than the max 128 entries that can fit in the e820 legacy
  * (zeropage) memory map.
  */
+enum add_efi_mode {
+	ADD_EFI_ALL,
+	ADD_EFI_APPLICATION_RESERVED,
+};
 
-static void __init do_add_efi_memmap(void)
+static void __init do_add_efi_memmap(enum add_efi_mode mode)
 {
 	efi_memory_desc_t *md;
+	int add = 0;
+
+	if (!efi_enabled(EFI_MEMMAP))
+		return;
 
 	for_each_efi_memory_desc(md) {
 		unsigned long long start = md->phys_addr;
@@ -142,7 +150,9 @@ static void __init do_add_efi_memmap(void)
 		case EFI_BOOT_SERVICES_CODE:
 		case EFI_BOOT_SERVICES_DATA:
 		case EFI_CONVENTIONAL_MEMORY:
-			if (md->attribute & EFI_MEMORY_WB)
+			if (is_efi_application_reserved(md))
+				e820_type = E820_TYPE_APPLICATION_RESERVED;
+			else if (md->attribute & EFI_MEMORY_WB)
 				e820_type = E820_TYPE_RAM;
 			else
 				e820_type = E820_TYPE_RESERVED;
@@ -168,9 +178,22 @@ static void __init do_add_efi_memmap(void)
 			e820_type = E820_TYPE_RESERVED;
 			break;
 		}
+
+		if (e820_type == E820_TYPE_APPLICATION_RESERVED)
+			/* always add E820_TYPE_APPLICATION_RESERVED */;
+		else if (mode != ADD_EFI_APPLICATION_RESERVED)
+			continue;
+
+		add++;
 		e820__range_add(start, size, e820_type);
 	}
-	e820__update_table(e820_table);
+	if (add)
+		e820__update_table(e820_table);
+}
+
+void __init efi_find_application_reserved(void)
+{
+	do_add_efi_memmap(ADD_EFI_APPLICATION_RESERVED);
 }
 
 int __init efi_memblock_x86_reserve_range(void)
@@ -203,7 +226,7 @@ int __init efi_memblock_x86_reserve_range(void)
 		return rv;
 
 	if (add_efi_memmap)
-		do_add_efi_memmap();
+		do_add_efi_memmap(ADD_EFI_ALL);
 
 	WARN(efi.memmap.desc_version != 1,
 	     "Unexpected EFI_MEMORY_DESCRIPTOR version %ld",
@@ -756,6 +779,12 @@ static bool should_map_region(efi_memory_desc_t *md)
 	if (IS_ENABLED(CONFIG_X86_32))
 		return false;
 
+	/*
+	 * Specific purpose memory is reserved by default.
+	 */
+	if (is_efi_application_reserved(md))
+		return false;
+
 	/*
 	 * Map all of RAM so that we can access arguments in the 1:1
 	 * mapping when making EFI runtime calls.
diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index da0ebaec25f0..2d79841ee9b9 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -133,6 +133,7 @@ enum {
 	IORES_DESC_PERSISTENT_MEMORY_LEGACY	= 5,
 	IORES_DESC_DEVICE_PRIVATE_MEMORY	= 6,
 	IORES_DESC_DEVICE_PUBLIC_MEMORY		= 7,
+	IORES_DESC_APPLICATION_RESERVED		= 8,
 };
 
 /* helpers to define resources */


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v4 06/10] x86, efi: Add efi_fake_mem support for EFI_MEMORY_SP
  2019-06-24 18:19 [PATCH v4 00/10] EFI Specific Purpose Memory Support Dan Williams
                   ` (4 preceding siblings ...)
  2019-06-24 18:19 ` [PATCH v4 05/10] x86, efi: Reserve UEFI 2.8 Specific Purpose Memory for dax Dan Williams
@ 2019-06-24 18:20 ` Dan Williams
  2019-06-24 18:20 ` [PATCH v4 07/10] resource: Uplevel the pmem "region" ida to a global allocator Dan Williams
                   ` (3 subsequent siblings)
  9 siblings, 0 replies; 21+ messages in thread
From: Dan Williams @ 2019-06-24 18:20 UTC (permalink / raw)
  To: x86
  Cc: Borislav Petkov, Ingo Molnar, H. Peter Anvin, Thomas Gleixner,
	Ard Biesheuvel, Dave Hansen, peterz, vishal.l.verma, tglx,
	linux-acpi, linux-nvdimm, linux-kernel

Given that EFI_MEMORY_SP is platform BIOS policy descision for marking
memory ranges as "reserved for a specific purpose" there will inevitably
be scenarios where the BIOS omits the attribute in situations where it
is desired. Unlike other attributes if the OS wants to reserve this
memory from the kernel the reservation needs to happen early in init. So
early, in fact, that it needs to happen before e820__memblock_setup()
which is a pre-requisite for efi_fake_memmap() that wants to allocate
memory for the updated table.

Introduce an x86 specific efi_fake_memmap_early() that can search for
attempts to set EFI_MEMORY_SP via efi_fake_mem and update the e820 table
accordingly.

Cc: <x86@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 arch/x86/include/asm/efi.h          |    8 ++++
 arch/x86/kernel/setup.c             |    1 +
 drivers/firmware/efi/Makefile       |    5 ++-
 drivers/firmware/efi/fake_mem.c     |   24 ++++++------
 drivers/firmware/efi/fake_mem.h     |   10 +++++
 drivers/firmware/efi/x86-fake_mem.c |   69 +++++++++++++++++++++++++++++++++++
 6 files changed, 103 insertions(+), 14 deletions(-)
 create mode 100644 drivers/firmware/efi/fake_mem.h
 create mode 100644 drivers/firmware/efi/x86-fake_mem.c

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 4f80254e0541..d6b18cedf0a8 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -275,4 +275,12 @@ static inline void __init efi_find_application_reserved(void)
 }
 #endif /* CONFIG_EFI */
 
+#ifdef CONFIG_EFI_FAKE_MEMMAP
+extern void __init efi_fake_memmap_early(void);
+#else
+static inline void efi_fake_memmap_early(void)
+{
+}
+#endif
+
 #endif /* _ASM_X86_EFI_H */
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 3b9001b7c951..3a7de6d6f106 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -1105,6 +1105,7 @@ void __init setup_arch(char **cmdline_p)
 	memblock_set_current_limit(ISA_END_ADDRESS);
 
 	efi_find_application_reserved();
+	efi_fake_memmap_early();
 	e820__memblock_setup();
 
 	reserve_bios_regions();
diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile
index d2d0d2030620..b06a9df6094c 100644
--- a/drivers/firmware/efi/Makefile
+++ b/drivers/firmware/efi/Makefile
@@ -20,12 +20,15 @@ obj-$(CONFIG_UEFI_CPER)			+= cper.o
 obj-$(CONFIG_EFI_RUNTIME_MAP)		+= runtime-map.o
 obj-$(CONFIG_EFI_RUNTIME_WRAPPERS)	+= runtime-wrappers.o
 obj-$(CONFIG_EFI_STUB)			+= libstub/
-obj-$(CONFIG_EFI_FAKE_MEMMAP)		+= fake_mem.o
+obj-$(CONFIG_EFI_FAKE_MEMMAP)		+= fake_map.o
 obj-$(CONFIG_EFI_BOOTLOADER_CONTROL)	+= efibc.o
 obj-$(CONFIG_EFI_TEST)			+= test/
 obj-$(CONFIG_EFI_DEV_PATH_PARSER)	+= dev-path-parser.o
 obj-$(CONFIG_APPLE_PROPERTIES)		+= apple-properties.o
 
+fake_map-y				+= fake_mem.o
+fake_map-$(CONFIG_X86)			+= x86-fake_mem.o
+
 arm-obj-$(CONFIG_EFI)			:= arm-init.o arm-runtime.o
 obj-$(CONFIG_ARM)			+= $(arm-obj-y)
 obj-$(CONFIG_ARM64)			+= $(arm-obj-y)
diff --git a/drivers/firmware/efi/fake_mem.c b/drivers/firmware/efi/fake_mem.c
index 526b45331d96..bb9fc70d0cfa 100644
--- a/drivers/firmware/efi/fake_mem.c
+++ b/drivers/firmware/efi/fake_mem.c
@@ -17,12 +17,10 @@
 #include <linux/memblock.h>
 #include <linux/types.h>
 #include <linux/sort.h>
-#include <asm/efi.h>
+#include "fake_mem.h"
 
-#define EFI_MAX_FAKEMEM CONFIG_EFI_MAX_FAKE_MEM
-
-static struct efi_mem_range fake_mems[EFI_MAX_FAKEMEM];
-static int nr_fake_mem;
+struct efi_mem_range efi_fake_mems[EFI_MAX_FAKEMEM];
+int nr_fake_mem;
 
 static int __init cmp_fake_mem(const void *x1, const void *x2)
 {
@@ -50,7 +48,7 @@ void __init efi_fake_memmap(void)
 	/* count up the number of EFI memory descriptor */
 	for (i = 0; i < nr_fake_mem; i++) {
 		for_each_efi_memory_desc(md) {
-			struct range *r = &fake_mems[i].range;
+			struct range *r = &efi_fake_mems[i].range;
 
 			new_nr_map += efi_memmap_split_count(md, r);
 		}
@@ -70,7 +68,7 @@ void __init efi_fake_memmap(void)
 	}
 
 	for (i = 0; i < nr_fake_mem; i++)
-		efi_memmap_insert(&efi.memmap, new_memmap, &fake_mems[i]);
+		efi_memmap_insert(&efi.memmap, new_memmap, &efi_fake_mems[i]);
 
 	/* swap into new EFI memmap */
 	early_memunmap(new_memmap, efi.memmap.desc_size * new_nr_map);
@@ -104,22 +102,22 @@ static int __init setup_fake_mem(char *p)
 		if (nr_fake_mem >= EFI_MAX_FAKEMEM)
 			break;
 
-		fake_mems[nr_fake_mem].range.start = start;
-		fake_mems[nr_fake_mem].range.end = start + mem_size - 1;
-		fake_mems[nr_fake_mem].attribute = attribute;
+		efi_fake_mems[nr_fake_mem].range.start = start;
+		efi_fake_mems[nr_fake_mem].range.end = start + mem_size - 1;
+		efi_fake_mems[nr_fake_mem].attribute = attribute;
 		nr_fake_mem++;
 
 		if (*p == ',')
 			p++;
 	}
 
-	sort(fake_mems, nr_fake_mem, sizeof(struct efi_mem_range),
+	sort(efi_fake_mems, nr_fake_mem, sizeof(struct efi_mem_range),
 	     cmp_fake_mem, NULL);
 
 	for (i = 0; i < nr_fake_mem; i++)
 		pr_info("efi_fake_mem: add attr=0x%016llx to [mem 0x%016llx-0x%016llx]",
-			fake_mems[i].attribute, fake_mems[i].range.start,
-			fake_mems[i].range.end);
+			efi_fake_mems[i].attribute, efi_fake_mems[i].range.start,
+			efi_fake_mems[i].range.end);
 
 	return *p == '\0' ? 0 : -EINVAL;
 }
diff --git a/drivers/firmware/efi/fake_mem.h b/drivers/firmware/efi/fake_mem.h
new file mode 100644
index 000000000000..0390be13df96
--- /dev/null
+++ b/drivers/firmware/efi/fake_mem.h
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0
+#ifndef __EFI_FAKE_MEM_H__
+#define __EFI_FAKE_MEM_H__
+#include <asm/efi.h>
+
+#define EFI_MAX_FAKEMEM CONFIG_EFI_MAX_FAKE_MEM
+
+extern struct efi_mem_range efi_fake_mems[EFI_MAX_FAKEMEM];
+extern int nr_fake_mem;
+#endif /* __EFI_FAKE_MEM_H__ */
diff --git a/drivers/firmware/efi/x86-fake_mem.c b/drivers/firmware/efi/x86-fake_mem.c
new file mode 100644
index 000000000000..3e9a80127562
--- /dev/null
+++ b/drivers/firmware/efi/x86-fake_mem.c
@@ -0,0 +1,69 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2019 Intel Corporation. All rights reserved. */
+#include <linux/efi.h>
+#include <asm/e820/api.h>
+#include "fake_mem.h"
+
+void __init efi_fake_memmap_early(void)
+{
+	int i;
+
+	/*
+	 * efi_fake_mem() can handle all possibilities if EFI_MEMORY_SP
+	 * is ignored.
+	 */
+	if (!IS_ENABLED(CONFIG_EFI_APPLICATION_RESERVED))
+		return;
+
+	if (!efi_enabled(EFI_MEMMAP) || !nr_fake_mem)
+		return;
+
+	/*
+	 * Given that efi_fake_memmap() needs to perform memblock
+	 * allocations it needs to run after e820__memblock_setup().
+	 * However, if efi_fake_mem specifies EFI_MEMORY_SP for a given
+	 * address range that potentially needs to mark the memory as
+	 * reserved prior to e820__memblock_setup(). Update e820
+	 * directly if EFI_MEMORY_SP is specified for an
+	 * EFI_CONVENTIONAL_MEMORY descriptor.
+	 */
+	for (i = 0; i < nr_fake_mem; i++) {
+		struct efi_mem_range *mem = &efi_fake_mems[i];
+		efi_memory_desc_t *md;
+		u64 m_start, m_end;
+
+		if ((mem->attribute & EFI_MEMORY_SP) == 0)
+			continue;
+
+		m_start = mem->range.start;
+		m_end = mem->range.end;
+		for_each_efi_memory_desc(md) {
+			u64 start, end;
+
+			if (md->type != EFI_CONVENTIONAL_MEMORY)
+				continue;
+
+			start = md->phys_addr;
+			end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1;
+
+			if (m_start <= end && m_end >= start)
+				/* fake range overlaps descriptor */;
+			else
+				continue;
+
+			/*
+			 * Trim the boundary of the e820 update to the
+			 * descriptor in case the fake range overlaps
+			 * !EFI_CONVENTIONAL_MEMORY
+			 */
+			start = max(start, m_start);
+			end = min(end, m_end);
+
+			if (end <= start)
+				continue;
+			e820__range_update(start, end - start + 1, E820_TYPE_RAM,
+					E820_TYPE_APPLICATION_RESERVED);
+			e820__update_table(e820_table);
+		}
+	}
+}


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v4 07/10] resource: Uplevel the pmem "region" ida to a global allocator
  2019-06-24 18:19 [PATCH v4 00/10] EFI Specific Purpose Memory Support Dan Williams
                   ` (5 preceding siblings ...)
  2019-06-24 18:20 ` [PATCH v4 06/10] x86, efi: Add efi_fake_mem support for EFI_MEMORY_SP Dan Williams
@ 2019-06-24 18:20 ` Dan Williams
  2019-06-24 18:20 ` [PATCH v4 08/10] device-dax: Add a driver for "hmem" devices Dan Williams
                   ` (2 subsequent siblings)
  9 siblings, 0 replies; 21+ messages in thread
From: Dan Williams @ 2019-06-24 18:20 UTC (permalink / raw)
  To: x86
  Cc: Keith Busch, Matthew Wilcox, peterz, vishal.l.verma, dave.hansen,
	ard.biesheuvel, tglx, linux-acpi, linux-nvdimm, linux-kernel

In preparation for handling platform differentiated memory types beyond
persistent memory, uplevel the "region" identifier to a global number
space. This enables a device-dax instance to be registered to any memory
type with guaranteed unique names.

Given this is a general identifier for persistent and
performance-differentiated memory, and a standalone header / source file
was NAK'd, house it with the rest of the general resource enumeration
implementation.

Cc: Keith Busch <keith.busch@intel.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 drivers/nvdimm/Kconfig       |    1 +
 drivers/nvdimm/core.c        |    1 -
 drivers/nvdimm/nd-core.h     |    1 -
 drivers/nvdimm/region_devs.c |   12 +++---------
 include/linux/ioport.h       |   27 +++++++++++++++++++++++++++
 kernel/resource.c            |    6 ++++++
 lib/Kconfig                  |    3 +++
 7 files changed, 40 insertions(+), 11 deletions(-)

diff --git a/drivers/nvdimm/Kconfig b/drivers/nvdimm/Kconfig
index 54500798f23a..4b3e66fe61c1 100644
--- a/drivers/nvdimm/Kconfig
+++ b/drivers/nvdimm/Kconfig
@@ -4,6 +4,7 @@ menuconfig LIBNVDIMM
 	depends on PHYS_ADDR_T_64BIT
 	depends on HAS_IOMEM
 	depends on BLK_DEV
+	select MEMREGION
 	help
 	  Generic support for non-volatile memory devices including
 	  ACPI-6-NFIT defined resources.  On platforms that define an
diff --git a/drivers/nvdimm/core.c b/drivers/nvdimm/core.c
index acce050856a8..75fe651d327d 100644
--- a/drivers/nvdimm/core.c
+++ b/drivers/nvdimm/core.c
@@ -463,7 +463,6 @@ static __exit void libnvdimm_exit(void)
 	nd_region_exit();
 	nvdimm_exit();
 	nvdimm_bus_exit();
-	nd_region_devs_exit();
 	nvdimm_devs_exit();
 }
 
diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h
index e5ffd5733540..17561302dfec 100644
--- a/drivers/nvdimm/nd-core.h
+++ b/drivers/nvdimm/nd-core.h
@@ -133,7 +133,6 @@ struct nvdimm_bus *walk_to_nvdimm_bus(struct device *nd_dev);
 int __init nvdimm_bus_init(void);
 void nvdimm_bus_exit(void);
 void nvdimm_devs_exit(void);
-void nd_region_devs_exit(void);
 void nd_region_probe_success(struct nvdimm_bus *nvdimm_bus, struct device *dev);
 struct nd_region;
 void nd_region_create_ns_seed(struct nd_region *nd_region);
diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c
index b4ef7d9ff22e..576c390dabd6 100644
--- a/drivers/nvdimm/region_devs.c
+++ b/drivers/nvdimm/region_devs.c
@@ -27,7 +27,6 @@
  */
 #include <linux/io-64-nonatomic-hi-lo.h>
 
-static DEFINE_IDA(region_ida);
 static DEFINE_PER_CPU(int, flush_idx);
 
 static int nvdimm_map_flush(struct device *dev, struct nvdimm *nvdimm, int dimm,
@@ -141,7 +140,7 @@ static void nd_region_release(struct device *dev)
 		put_device(&nvdimm->dev);
 	}
 	free_percpu(nd_region->lane);
-	ida_simple_remove(&region_ida, nd_region->id);
+	memregion_free(nd_region->id);
 	if (is_nd_blk(dev))
 		kfree(to_nd_blk_region(dev));
 	else
@@ -1036,7 +1035,7 @@ static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
 
 	if (!region_buf)
 		return NULL;
-	nd_region->id = ida_simple_get(&region_ida, 0, 0, GFP_KERNEL);
+	nd_region->id = memregion_alloc(GFP_KERNEL);
 	if (nd_region->id < 0)
 		goto err_id;
 
@@ -1090,7 +1089,7 @@ static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
 	return nd_region;
 
  err_percpu:
-	ida_simple_remove(&region_ida, nd_region->id);
+	memregion_free(nd_region->id);
  err_id:
 	kfree(region_buf);
 	return NULL;
@@ -1237,8 +1236,3 @@ int nd_region_conflict(struct nd_region *nd_region, resource_size_t start,
 
 	return device_for_each_child(&nvdimm_bus->dev, &ctx, region_conflict);
 }
-
-void __exit nd_region_devs_exit(void)
-{
-	ida_destroy(&region_ida);
-}
diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index 2d79841ee9b9..72ea690b35a4 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -12,6 +12,12 @@
 #ifndef __ASSEMBLY__
 #include <linux/compiler.h>
 #include <linux/types.h>
+#ifdef CONFIG_MEMREGION
+#include <linux/idr.h>
+#else
+#include <linux/errno.h>
+#endif
+
 /*
  * Resources are tree-like, allowing
  * nesting etc..
@@ -287,6 +293,27 @@ static inline bool resource_overlaps(struct resource *r1, struct resource *r2)
        return (r1->start <= r2->end && r1->end >= r2->start);
 }
 
+#ifdef CONFIG_MEMREGION
+extern struct ida memregion_ids;
+static inline int memregion_alloc(gfp_t gfp)
+{
+	return ida_alloc(&memregion_ids, gfp);
+}
+
+static inline void memregion_free(int id)
+{
+	ida_free(&memregion_ids, id);
+}
+#else /* CONFIG_MEMREGION */
+static inline int memregion_alloc(gfp_t gfp)
+{
+	return -ENOMEM;
+}
+
+static inline void memregion_free(int id)
+{
+}
+#endif
 
 #endif /* __ASSEMBLY__ */
 #endif	/* _LINUX_IOPORT_H */
diff --git a/kernel/resource.c b/kernel/resource.c
index 158f04ec1d4f..82dbd9f28e91 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -1637,4 +1637,10 @@ static int __init strict_iomem(char *str)
 	return 1;
 }
 
+#ifdef CONFIG_MEMREGION
+/* identifiers for device memory regions */
+DEFINE_IDA(memregion_ids);
+EXPORT_SYMBOL(memregion_ids);
+#endif
+
 __setup("iomem=", strict_iomem);
diff --git a/lib/Kconfig b/lib/Kconfig
index 90623a0e1942..89f7e4523799 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -602,6 +602,9 @@ config ARCH_NO_SG_CHAIN
 config ARCH_HAS_PMEM_API
 	bool
 
+config MEMREGION
+	bool
+
 # use memcpy to implement user copies for nommu architectures
 config UACCESS_MEMCPY
 	bool


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v4 08/10] device-dax: Add a driver for "hmem" devices
  2019-06-24 18:19 [PATCH v4 00/10] EFI Specific Purpose Memory Support Dan Williams
                   ` (6 preceding siblings ...)
  2019-06-24 18:20 ` [PATCH v4 07/10] resource: Uplevel the pmem "region" ida to a global allocator Dan Williams
@ 2019-06-24 18:20 ` Dan Williams
  2019-06-25 15:37   ` Jonathan Cameron
  2019-06-24 18:20 ` [PATCH v4 09/10] acpi/numa/hmat: Register HMAT at device_initcall level Dan Williams
  2019-06-24 18:20 ` [PATCH v4 10/10] acpi/numa/hmat: Register "specific purpose" memory as an "hmem" device Dan Williams
  9 siblings, 1 reply; 21+ messages in thread
From: Dan Williams @ 2019-06-24 18:20 UTC (permalink / raw)
  To: x86
  Cc: Vishal Verma, Keith Busch, Dave Jiang, kbuild test robot,
	Dave Hansen, peterz, ard.biesheuvel, tglx, linux-acpi,
	linux-nvdimm, linux-kernel

Platform firmware like EFI/ACPI may publish "hmem" platform devices.
Such a device is a performance differentiated memory range likely
reserved for an application specific use case. The driver gives access
to 100% of the capacity via a device-dax mmap instance by default.

However, if over-subscription and other kernel memory management is
desired the resulting dax device can be assigned to the core-mm via the
kmem driver.

This consumes "hmem" devices the producer of "hmem" devices is saved for
a follow-on patch so that it can reference the new CONFIG_DEV_DAX_HMEM
symbol to gate performing the enumeration work.

Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Reported-by: kbuild test robot <lkp@intel.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 drivers/dax/Kconfig    |   27 +++++++++++++++++++----
 drivers/dax/Makefile   |    2 ++
 drivers/dax/hmem.c     |   57 ++++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/ioport.h |    4 +++
 4 files changed, 85 insertions(+), 5 deletions(-)
 create mode 100644 drivers/dax/hmem.c

diff --git a/drivers/dax/Kconfig b/drivers/dax/Kconfig
index f33c73e4af41..1a59ef86f148 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_APPLICATION_RESERVED
+	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/hmem.c b/drivers/dax/hmem.c
new file mode 100644
index 000000000000..62f9e3c80e21
--- /dev/null
+++ b/drivers/dax/hmem.c
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/platform_device.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/pfn_t.h>
+#include "bus.h"
+
+static int dax_hmem_probe(struct platform_device *pdev)
+{
+	struct dev_pagemap pgmap = { NULL };
+	struct device *dev = &pdev->dev;
+	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;
+	pgmap.dev = dev;
+	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");
diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index 72ea690b35a4..0c529c8f8027 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -294,6 +294,10 @@ static inline bool resource_overlaps(struct resource *r1, struct resource *r2)
 }
 
 #ifdef CONFIG_MEMREGION
+struct memregion_info {
+	int target_node;
+};
+
 extern struct ida memregion_ids;
 static inline int memregion_alloc(gfp_t gfp)
 {


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v4 09/10] acpi/numa/hmat: Register HMAT at device_initcall level
  2019-06-24 18:19 [PATCH v4 00/10] EFI Specific Purpose Memory Support Dan Williams
                   ` (7 preceding siblings ...)
  2019-06-24 18:20 ` [PATCH v4 08/10] device-dax: Add a driver for "hmem" devices Dan Williams
@ 2019-06-24 18:20 ` Dan Williams
  2019-07-03 11:12   ` Rafael J. Wysocki
  2019-06-24 18:20 ` [PATCH v4 10/10] acpi/numa/hmat: Register "specific purpose" memory as an "hmem" device Dan Williams
  9 siblings, 1 reply; 21+ messages in thread
From: Dan Williams @ 2019-06-24 18:20 UTC (permalink / raw)
  To: x86
  Cc: Rafael J. Wysocki, Len Brown, Keith Busch, Jonathan Cameron,
	Dave Hansen, peterz, vishal.l.verma, ard.biesheuvel, tglx,
	linux-acpi, linux-nvdimm, linux-kernel

In preparation for registering device-dax instances for accessing EFI
specific-purpose memory, arrange for the HMAT registration to occur
later in the init process. Critically HMAT initialization needs to occur
after e820__reserve_resources_late() which is the point at which the
iomem resource tree is populated with "Application Reserved"
(IORES_DESC_APPLICATION_RESERVED). e820__reserve_resources_late()
happens at subsys_initcall time.

Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Len Brown <lenb@kernel.org>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 drivers/acpi/numa/hmat.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c
index 2c220cb7b620..1d329c4af3bf 100644
--- a/drivers/acpi/numa/hmat.c
+++ b/drivers/acpi/numa/hmat.c
@@ -671,4 +671,4 @@ static __init int hmat_init(void)
 	acpi_put_table(tbl);
 	return 0;
 }
-subsys_initcall(hmat_init);
+device_initcall(hmat_init);


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* [PATCH v4 10/10] acpi/numa/hmat: Register "specific purpose" memory as an "hmem" device
  2019-06-24 18:19 [PATCH v4 00/10] EFI Specific Purpose Memory Support Dan Williams
                   ` (8 preceding siblings ...)
  2019-06-24 18:20 ` [PATCH v4 09/10] acpi/numa/hmat: Register HMAT at device_initcall level Dan Williams
@ 2019-06-24 18:20 ` Dan Williams
  2019-06-25 15:58   ` Jonathan Cameron
  2019-07-03 11:17   ` Rafael J. Wysocki
  9 siblings, 2 replies; 21+ messages in thread
From: Dan Williams @ 2019-06-24 18:20 UTC (permalink / raw)
  To: x86
  Cc: Len Brown, Keith Busch, Rafael J. Wysocki, Vishal Verma,
	Jonathan Cameron, Dave Hansen, peterz, ard.biesheuvel, tglx,
	linux-acpi, linux-nvdimm, linux-kernel

Memory that has been tagged EFI_MEMORY_SP, and has performance
properties described by the ACPI HMAT is expected to have an application
specific consumer.

Those consumers may want 100% of the memory capacity to be reserved from
any usage by the kernel. By default, with this enabling, a platform
device is created to represent this differentiated resource.

The device-dax "hmem" driver claims these devices by default and
provides an mmap interface for the target application.  If the
administrator prefers, the hmem resource range can be made available to
the core-mm via the device-dax hotplug facility, kmem, to online the
memory with its own numa node.

This was tested with an emulated HMAT produced by qemu (with the pending
HMAT enabling patches), and "efi_fake_mem=8G@9G:0x40000" on the kernel
command line to mark the memory ranges associated with node2 and node3
as EFI_MEMORY_SP.

qemu numa configuration options:

-numa node,mem=4G,cpus=0-19,nodeid=0
-numa node,mem=4G,cpus=20-39,nodeid=1
-numa node,mem=4G,nodeid=2
-numa node,mem=4G,nodeid=3
-numa dist,src=0,dst=0,val=10
-numa dist,src=0,dst=1,val=21
-numa dist,src=0,dst=2,val=21
-numa dist,src=0,dst=3,val=21
-numa dist,src=1,dst=0,val=21
-numa dist,src=1,dst=1,val=10
-numa dist,src=1,dst=2,val=21
-numa dist,src=1,dst=3,val=21
-numa dist,src=2,dst=0,val=21
-numa dist,src=2,dst=1,val=21
-numa dist,src=2,dst=2,val=10
-numa dist,src=2,dst=3,val=21
-numa dist,src=3,dst=0,val=21
-numa dist,src=3,dst=1,val=21
-numa dist,src=3,dst=2,val=21
-numa dist,src=3,dst=3,val=10
-numa hmat-lb,initiator=0,target=0,hierarchy=memory,data-type=access-latency,base-lat=10,latency=5
-numa hmat-lb,initiator=0,target=0,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=5
-numa hmat-lb,initiator=0,target=1,hierarchy=memory,data-type=access-latency,base-lat=10,latency=10
-numa hmat-lb,initiator=0,target=1,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=10
-numa hmat-lb,initiator=0,target=2,hierarchy=memory,data-type=access-latency,base-lat=10,latency=15
-numa hmat-lb,initiator=0,target=2,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=15
-numa hmat-lb,initiator=0,target=3,hierarchy=memory,data-type=access-latency,base-lat=10,latency=20
-numa hmat-lb,initiator=0,target=3,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=20
-numa hmat-lb,initiator=1,target=0,hierarchy=memory,data-type=access-latency,base-lat=10,latency=10
-numa hmat-lb,initiator=1,target=0,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=10
-numa hmat-lb,initiator=1,target=1,hierarchy=memory,data-type=access-latency,base-lat=10,latency=5
-numa hmat-lb,initiator=1,target=1,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=5
-numa hmat-lb,initiator=1,target=2,hierarchy=memory,data-type=access-latency,base-lat=10,latency=15
-numa hmat-lb,initiator=1,target=2,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=15
-numa hmat-lb,initiator=1,target=3,hierarchy=memory,data-type=access-latency,base-lat=10,latency=20
-numa hmat-lb,initiator=1,target=3,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=20

Result:

# daxctl list -RDu
[
  {
    "path":"\/platform\/hmem.1",
    "id":1,
    "size":"4.00 GiB (4.29 GB)",
    "align":2097152,
    "devices":[
      {
        "chardev":"dax1.0",
        "size":"4.00 GiB (4.29 GB)"
      }
    ]
  },
  {
    "path":"\/platform\/hmem.0",
    "id":0,
    "size":"4.00 GiB (4.29 GB)",
    "align":2097152,
    "devices":[
      {
        "chardev":"dax0.0",
        "size":"4.00 GiB (4.29 GB)"
      }
    ]
  }
]

# cat /proc/iomem
[..]
240000000-43fffffff : Application Reserved
  240000000-33fffffff : hmem.0
    240000000-33fffffff : dax0.0
  340000000-43fffffff : hmem.1
    340000000-43fffffff : dax1.0

Cc: Len Brown <lenb@kernel.org>
Cc: Keith Busch <keith.busch@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 drivers/acpi/numa/Kconfig |    1 
 drivers/acpi/numa/hmat.c  |  132 +++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 122 insertions(+), 11 deletions(-)

diff --git a/drivers/acpi/numa/Kconfig b/drivers/acpi/numa/Kconfig
index d14582387ed0..c1be746e111a 100644
--- a/drivers/acpi/numa/Kconfig
+++ b/drivers/acpi/numa/Kconfig
@@ -8,6 +8,7 @@ config ACPI_HMAT
 	bool "ACPI Heterogeneous Memory Attribute Table Support"
 	depends on ACPI_NUMA
 	select HMEM_REPORTING
+	select MEMREGION
 	help
 	 If set, this option has the kernel parse and report the
 	 platform's ACPI HMAT (Heterogeneous Memory Attributes Table),
diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c
index 1d329c4af3bf..622c5feb3aa0 100644
--- a/drivers/acpi/numa/hmat.c
+++ b/drivers/acpi/numa/hmat.c
@@ -8,11 +8,16 @@
  * the applicable attributes with the node's interfaces.
  */
 
+#define pr_fmt(fmt) "acpi/hmat: " fmt
+#define dev_fmt(fmt) "acpi/hmat: " fmt
+
 #include <linux/acpi.h>
 #include <linux/bitops.h>
 #include <linux/device.h>
 #include <linux/init.h>
 #include <linux/list.h>
+#include <linux/mm.h>
+#include <linux/platform_device.h>
 #include <linux/list_sort.h>
 #include <linux/node.h>
 #include <linux/sysfs.h>
@@ -40,6 +45,7 @@ struct memory_target {
 	struct list_head node;
 	unsigned int memory_pxm;
 	unsigned int processor_pxm;
+	struct resource memregions;
 	struct node_hmem_attrs hmem_attrs;
 };
 
@@ -92,21 +98,35 @@ static __init void alloc_memory_initiator(unsigned int cpu_pxm)
 	list_add_tail(&initiator->node, &initiators);
 }
 
-static __init void alloc_memory_target(unsigned int mem_pxm)
+static __init void alloc_memory_target(unsigned int mem_pxm,
+		resource_size_t start, resource_size_t len)
 {
 	struct memory_target *target;
 
 	target = find_mem_target(mem_pxm);
-	if (target)
-		return;
-
-	target = kzalloc(sizeof(*target), GFP_KERNEL);
-	if (!target)
-		return;
+	if (!target) {
+		target = kzalloc(sizeof(*target), GFP_KERNEL);
+		if (!target)
+			return;
+		target->memory_pxm = mem_pxm;
+		target->processor_pxm = PXM_INVAL;
+		target->memregions = (struct resource) {
+			.name	= "ACPI mem",
+			.start	= 0,
+			.end	= -1,
+			.flags	= IORESOURCE_MEM,
+		};
+		list_add_tail(&target->node, &targets);
+	}
 
-	target->memory_pxm = mem_pxm;
-	target->processor_pxm = PXM_INVAL;
-	list_add_tail(&target->node, &targets);
+	/*
+	 * There are potentially multiple ranges per PXM, so record each
+	 * in the per-target memregions resource tree.
+	 */
+	if (!__request_region(&target->memregions, start, len, "memory target",
+				IORESOURCE_MEM))
+		pr_warn("failed to reserve %#llx - %#llx in pxm: %d\n",
+				start, start + len, mem_pxm);
 }
 
 static __init const char *hmat_data_type(u8 type)
@@ -428,7 +448,7 @@ static __init int srat_parse_mem_affinity(union acpi_subtable_headers *header,
 		return -EINVAL;
 	if (!(ma->flags & ACPI_SRAT_MEM_ENABLED))
 		return 0;
-	alloc_memory_target(ma->proximity_domain);
+	alloc_memory_target(ma->proximity_domain, ma->base_address, ma->length);
 	return 0;
 }
 
@@ -580,6 +600,81 @@ static __init void hmat_register_target_perf(struct memory_target *target)
 	node_set_perf_attrs(mem_nid, &target->hmem_attrs, 0);
 }
 
+static __init void hmat_register_target_device(struct memory_target *target,
+		struct resource *r)
+{
+	/* define a clean / non-busy resource for the platform device */
+	struct resource res = {
+		.start = r->start,
+		.end = r->end,
+		.flags = IORESOURCE_MEM,
+	};
+	struct platform_device *pdev;
+	struct memregion_info info;
+	int rc, id;
+
+	rc = region_intersects(res.start, resource_size(&res), IORESOURCE_MEM,
+			IORES_DESC_APPLICATION_RESERVED);
+	if (rc != REGION_INTERSECTS)
+		return;
+
+	id = memregion_alloc(GFP_KERNEL);
+	if (id < 0) {
+		pr_err("memregion allocation failure for %pr\n", &res);
+		return;
+	}
+
+	pdev = platform_device_alloc("hmem", id);
+	if (!pdev) {
+		pr_err("hmem device allocation failure for %pr\n", &res);
+		goto out_pdev;
+	}
+
+	pdev->dev.numa_node = acpi_map_pxm_to_online_node(target->memory_pxm);
+	info = (struct memregion_info) {
+		.target_node = acpi_map_pxm_to_node(target->memory_pxm),
+	};
+	rc = platform_device_add_data(pdev, &info, sizeof(info));
+	if (rc < 0) {
+		pr_err("hmem memregion_info allocation failure for %pr\n", &res);
+		goto out_pdev;
+	}
+
+	rc = platform_device_add_resources(pdev, &res, 1);
+	if (rc < 0) {
+		pr_err("hmem resource allocation failure for %pr\n", &res);
+		goto out_resource;
+	}
+
+	rc = platform_device_add(pdev);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "device add failed for %pr\n", &res);
+		goto out_resource;
+	}
+
+	return;
+
+out_resource:
+	put_device(&pdev->dev);
+out_pdev:
+	memregion_free(id);
+}
+
+static __init void hmat_register_target_devices(struct memory_target *target)
+{
+	struct resource *res;
+
+	/*
+	 * Do not bother creating devices if no driver is available to
+	 * consume them.
+	 */
+	if (!IS_ENABLED(CONFIG_DEV_DAX_HMEM))
+		return;
+
+	for (res = target->memregions.child; res; res = res->sibling)
+		hmat_register_target_device(target, res);
+}
+
 static __init void hmat_register_targets(void)
 {
 	struct memory_target *target;
@@ -587,6 +682,12 @@ static __init void hmat_register_targets(void)
 	list_for_each_entry(target, &targets, node) {
 		int nid = pxm_to_node(target->memory_pxm);
 
+		/*
+		 * Devices may belong to either an offline or online
+		 * node, so unconditionally add them.
+		 */
+		hmat_register_target_devices(target);
+
 		/*
 		 * Skip offline nodes. This can happen when memory
 		 * marked EFI_MEMORY_SP, "specific purpose", is applied
@@ -608,7 +709,16 @@ static __init void hmat_free_structures(void)
 	struct memory_initiator *initiator, *inext;
 
 	list_for_each_entry_safe(target, tnext, &targets, node) {
+		struct resource *res, *res_next;
+
 		list_del(&target->node);
+		res = target->memregions.child;
+		while (res) {
+			res_next = res->sibling;
+			__release_region(&target->memregions, res->start,
+					resource_size(res));
+			res = res_next;
+		}
 		kfree(target);
 	}
 


^ permalink raw reply related	[flat|nested] 21+ messages in thread

* Re: [PATCH v4 01/10] acpi/numa: Establish a new drivers/acpi/numa/ directory
  2019-06-24 18:19 ` [PATCH v4 01/10] acpi/numa: Establish a new drivers/acpi/numa/ directory Dan Williams
@ 2019-06-25 14:59   ` Jonathan Cameron
  2019-06-25 16:02     ` Dan Williams
  2019-07-03 11:09   ` Rafael J. Wysocki
  1 sibling, 1 reply; 21+ messages in thread
From: Jonathan Cameron @ 2019-06-25 14:59 UTC (permalink / raw)
  To: Dan Williams
  Cc: x86, Len Brown, Keith Busch, Rafael J. Wysocki, Dave Hansen,
	peterz, vishal.l.verma, ard.biesheuvel, tglx, linux-acpi,
	linux-nvdimm, linux-kernel

On Mon, 24 Jun 2019 11:19:32 -0700
Dan Williams <dan.j.williams@intel.com> wrote:

> Currently hmat.c lives under an "hmat" directory which does not enhance
> the description of the file. The initial motivation for giving hmat.c
> its own directory was to delineate it as mm functionality in contrast to
> ACPI device driver functionality.
> 
> As ACPI continues to play an increasing role in conveying
> memory location and performance topology information to the OS take the
> opportunity to co-locate these NUMA relevant tables in a combined
> directory.
> 
> numa.c is renamed to srat.c and moved to drivers/acpi/numa/ along with
> hmat.c.

Hi Dan,

srat.c now includes processing for the slit table which is a bit odd.

Now we could split this up in to a top level numa.c and then
srat.c, slit.c and hmat.c....

Does feel rather silly though.  Perhaps better to just leave it as
numa.c?

I don't really feel strongly about this though.

Jonathan

> 
> Cc: Len Brown <lenb@kernel.org>
> Cc: Keith Busch <keith.busch@intel.com>
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
> ---
>  drivers/acpi/Kconfig       |    9 +--------
>  drivers/acpi/Makefile      |    3 +--
>  drivers/acpi/hmat/Makefile |    2 --
>  drivers/acpi/numa/Kconfig  |    7 ++++++-
>  drivers/acpi/numa/Makefile |    3 +++
>  drivers/acpi/numa/hmat.c   |    0 
>  drivers/acpi/numa/srat.c   |    0 
>  7 files changed, 11 insertions(+), 13 deletions(-)
>  delete mode 100644 drivers/acpi/hmat/Makefile
>  rename drivers/acpi/{hmat/Kconfig => numa/Kconfig} (72%)
>  create mode 100644 drivers/acpi/numa/Makefile
>  rename drivers/acpi/{hmat/hmat.c => numa/hmat.c} (100%)
>  rename drivers/acpi/{numa.c => numa/srat.c} (100%)
> 
> diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
> index 283ee94224c6..82c4a31c8701 100644
> --- a/drivers/acpi/Kconfig
> +++ b/drivers/acpi/Kconfig
> @@ -321,12 +321,6 @@ config ACPI_THERMAL
>  	  To compile this driver as a module, choose M here:
>  	  the module will be called thermal.
>  
> -config ACPI_NUMA
> -	bool "NUMA support"
> -	depends on NUMA
> -	depends on (X86 || IA64 || ARM64)
> -	default y if IA64_GENERIC || IA64_SGI_SN2 || ARM64
> -
>  config ACPI_CUSTOM_DSDT_FILE
>  	string "Custom DSDT Table file to include"
>  	default ""
> @@ -475,8 +469,7 @@ config ACPI_REDUCED_HARDWARE_ONLY
>  	  If you are unsure what to do, do not enable this option.
>  
>  source "drivers/acpi/nfit/Kconfig"
> -source "drivers/acpi/hmat/Kconfig"
> -
> +source "drivers/acpi/numa/Kconfig"
>  source "drivers/acpi/apei/Kconfig"
>  source "drivers/acpi/dptf/Kconfig"
>  
> diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
> index 5d361e4e3405..f08a661274e8 100644
> --- a/drivers/acpi/Makefile
> +++ b/drivers/acpi/Makefile
> @@ -55,7 +55,6 @@ acpi-$(CONFIG_X86)		+= acpi_cmos_rtc.o
>  acpi-$(CONFIG_X86)		+= x86/apple.o
>  acpi-$(CONFIG_X86)		+= x86/utils.o
>  acpi-$(CONFIG_DEBUG_FS)		+= debugfs.o
> -acpi-$(CONFIG_ACPI_NUMA)	+= numa.o
>  acpi-$(CONFIG_ACPI_PROCFS_POWER) += cm_sbs.o
>  acpi-y				+= acpi_lpat.o
>  acpi-$(CONFIG_ACPI_LPIT)	+= acpi_lpit.o
> @@ -80,7 +79,7 @@ obj-$(CONFIG_ACPI_PROCESSOR)	+= processor.o
>  obj-$(CONFIG_ACPI)		+= container.o
>  obj-$(CONFIG_ACPI_THERMAL)	+= thermal.o
>  obj-$(CONFIG_ACPI_NFIT)		+= nfit/
> -obj-$(CONFIG_ACPI_HMAT)		+= hmat/
> +obj-$(CONFIG_ACPI_NUMA)		+= numa/
>  obj-$(CONFIG_ACPI)		+= acpi_memhotplug.o
>  obj-$(CONFIG_ACPI_HOTPLUG_IOAPIC) += ioapic.o
>  obj-$(CONFIG_ACPI_BATTERY)	+= battery.o
> diff --git a/drivers/acpi/hmat/Makefile b/drivers/acpi/hmat/Makefile
> deleted file mode 100644
> index 1c20ef36a385..000000000000
> --- a/drivers/acpi/hmat/Makefile
> +++ /dev/null
> @@ -1,2 +0,0 @@
> -# SPDX-License-Identifier: GPL-2.0-only
> -obj-$(CONFIG_ACPI_HMAT) := hmat.o
> diff --git a/drivers/acpi/hmat/Kconfig b/drivers/acpi/numa/Kconfig
> similarity index 72%
> rename from drivers/acpi/hmat/Kconfig
> rename to drivers/acpi/numa/Kconfig
> index 95a29964dbea..d14582387ed0 100644
> --- a/drivers/acpi/hmat/Kconfig
> +++ b/drivers/acpi/numa/Kconfig
> @@ -1,4 +1,9 @@
> -# SPDX-License-Identifier: GPL-2.0
> +config ACPI_NUMA
> +	bool "NUMA support"
> +	depends on NUMA
> +	depends on (X86 || IA64 || ARM64)
> +	default y if IA64_GENERIC || IA64_SGI_SN2 || ARM64
> +
>  config ACPI_HMAT
>  	bool "ACPI Heterogeneous Memory Attribute Table Support"
>  	depends on ACPI_NUMA
> diff --git a/drivers/acpi/numa/Makefile b/drivers/acpi/numa/Makefile
> new file mode 100644
> index 000000000000..517a6c689a94
> --- /dev/null
> +++ b/drivers/acpi/numa/Makefile
> @@ -0,0 +1,3 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +obj-$(CONFIG_ACPI_NUMA) += srat.o
> +obj-$(CONFIG_ACPI_HMAT) += hmat.o
> diff --git a/drivers/acpi/hmat/hmat.c b/drivers/acpi/numa/hmat.c
> similarity index 100%
> rename from drivers/acpi/hmat/hmat.c
> rename to drivers/acpi/numa/hmat.c
> diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa/srat.c
> similarity index 100%
> rename from drivers/acpi/numa.c
> rename to drivers/acpi/numa/srat.c
> 



^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v4 05/10] x86, efi: Reserve UEFI 2.8 Specific Purpose Memory for dax
  2019-06-24 18:19 ` [PATCH v4 05/10] x86, efi: Reserve UEFI 2.8 Specific Purpose Memory for dax Dan Williams
@ 2019-06-25 15:26   ` Jonathan Cameron
  0 siblings, 0 replies; 21+ messages in thread
From: Jonathan Cameron @ 2019-06-25 15:26 UTC (permalink / raw)
  To: Dan Williams
  Cc: x86, Borislav Petkov, Ingo Molnar, H. Peter Anvin, Darren Hart,
	Andy Shevchenko, Andy Lutomirski, Peter Zijlstra,
	Thomas Gleixner, Ard Biesheuvel, kbuild test robot, Dave Hansen,
	vishal.l.verma, linux-acpi, linux-nvdimm, linux-kernel

On Mon, 24 Jun 2019 11:19:55 -0700
Dan Williams <dan.j.williams@intel.com> wrote:

> UEFI 2.8 defines an EFI_MEMORY_SP attribute bit to augment the
> interpretation of the EFI Memory Types as "reserved for a specific
> purpose".
> 
> The proposed Linux behavior for specific purpose memory is that it is
> reserved for direct-access (device-dax) by default and not available for
> any kernel usage, not even as an OOM fallback.  Later, through udev
> scripts or another init mechanism, these device-dax claimed ranges can
> be reconfigured and hot-added to the available System-RAM with a unique
> node identifier.
> 
> This patch introduces 2 new concepts at once given the entanglement
> between early boot enumeration relative to memory that can optionally be
> reserved from the kernel page allocator by default. The new concepts
> are:
> 
> - E820_TYPE_APPLICATION_RESERVED: Upon detecting the EFI_MEMORY_SP
>   attribute on EFI_CONVENTIONAL memory, update the E820 map with this
>   new type. Only perform this classification if the
>   CONFIG_EFI_SPECIFIC_DAX=y policy is enabled, otherwise treat it as
>   typical ram.
> 
> - IORES_DESC_APPLICATION_RESERVED: Add a new I/O resource descriptor for
>   a device driver to search iomem resources for application specific
>   memory. Teach the iomem code to identify such ranges as "Application
>   Reserved".
> 
> A follow-on change integrates parsing of the ACPI HMAT to identify the
> node and sub-range boundaries of EFI_MEMORY_SP designated memory. For
> now, just identify and reserve memory of this type.
> 
> For now this translation of EFI_CONVENTIONAL + EFI_MEMORY_SP is
> x86/E820-only, but other archs could choose to publish
> IORES_DESC_APPLICATION_RESERVED resources from their platform-firmware
> memory map handlers.
> 
> Cc: <x86@kernel.org>
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: Ingo Molnar <mingo@redhat.com>
> Cc: "H. Peter Anvin" <hpa@zytor.com>
> Cc: Darren Hart <dvhart@infradead.org>
> Cc: Andy Shevchenko <andy@infradead.org>
> Cc: Andy Lutomirski <luto@kernel.org>
> Cc: Peter Zijlstra <peterz@infradead.org>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> Reported-by: kbuild test robot <lkp@intel.com>
> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
A few really minor things inline.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> ---
>  arch/x86/Kconfig                  |   23 +++++++++++++++++++++++
>  arch/x86/boot/compressed/eboot.c  |    5 ++++-
>  arch/x86/boot/compressed/kaslr.c  |    3 ++-
>  arch/x86/include/asm/e820/types.h |    9 +++++++++
>  arch/x86/include/asm/efi.h        |   17 +++++++++++++++++
>  arch/x86/kernel/e820.c            |   12 ++++++++++--
>  arch/x86/kernel/setup.c           |    1 +
>  arch/x86/platform/efi/efi.c       |   37 +++++++++++++++++++++++++++++++++----
>  include/linux/ioport.h            |    1 +
>  9 files changed, 100 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 2bbbd4d1ba31..d8d3b4e87ac1 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -1955,6 +1955,29 @@ config EFI_MIXED
>  
>  	   If unsure, say N.
>  
> +config EFI_APPLICATION_RESERVED
> +	bool "Reserve EFI Specific Purpose Memory"
> +	depends on ACPI_HMAT
> +	default ACPI_HMAT
> +	depends on EFI
> +	---help---
> +	  On systems that have mixed performance classes of memory EFI
> +	  may indicate specific purpose memory with an attribute (See
> +	  EFI_MEMORY_SP in UEFI 2.8). A memory range tagged with this
> +	  attribute may have unique performance characteristics compared
> +	  to the system's general purpose "System RAM" pool. On the
> +	  expectation that such memory has application specific usage,
> +	  and its base EFI memory type is "conventional" answer Y to
> +	  arrange for the kernel to reserve it as an "Application
> +	  Reserved" resource, and set aside for direct-access
> +	  (device-dax) by default. The memory range can later be
> +	  optionally assigned to the page allocator by system
> +	  administrator policy via the device-dax kmem facility. Say N
> +	  to have the kernel treat this memory as "System RAM" by
> +	  default.
> +
> +	  If unsure, say Y.
> +
>  config SECCOMP
>  	def_bool y
>  	prompt "Enable seccomp to safely compute untrusted bytecode"
> diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
> index 544ac4fafd11..a6c96eb6e633 100644
> --- a/arch/x86/boot/compressed/eboot.c
> +++ b/arch/x86/boot/compressed/eboot.c
> @@ -560,7 +560,10 @@ setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_s
>  		case EFI_BOOT_SERVICES_CODE:
>  		case EFI_BOOT_SERVICES_DATA:
>  		case EFI_CONVENTIONAL_MEMORY:
> -			e820_type = E820_TYPE_RAM;
> +			if (is_efi_application_reserved(d))
> +				e820_type = E820_TYPE_APPLICATION_RESERVED;
> +			else
> +				e820_type = E820_TYPE_RAM;
>  			break;
>  
>  		case EFI_ACPI_MEMORY_NVS:
> diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c
> index 2e53c056ba20..e8306f452182 100644
> --- a/arch/x86/boot/compressed/kaslr.c
> +++ b/arch/x86/boot/compressed/kaslr.c
> @@ -757,7 +757,8 @@ process_efi_entries(unsigned long minimum, unsigned long image_size)
>  		 *
>  		 * Only EFI_CONVENTIONAL_MEMORY is guaranteed to be free.
>  		 */
> -		if (md->type != EFI_CONVENTIONAL_MEMORY)
> +		if (md->type != EFI_CONVENTIONAL_MEMORY
> +				|| is_efi_application_reserved(md))
>  			continue;
>  
>  		if (efi_mirror_found &&
> diff --git a/arch/x86/include/asm/e820/types.h b/arch/x86/include/asm/e820/types.h
> index c3aa4b5e49e2..41193c116a1f 100644
> --- a/arch/x86/include/asm/e820/types.h
> +++ b/arch/x86/include/asm/e820/types.h
> @@ -28,6 +28,15 @@ enum e820_type {
>  	 */
>  	E820_TYPE_PRAM		= 12,
>  
> +	/*
> +	 * Special-purpose / application-specific memory is indicated to
> +	 * the system via the EFI_MEMORY_SP attribute. Define an e820
> +	 * translation of this memory type for the purpose of
> +	 * reserving this range and marking it with the
> +	 * IORES_DESC_APPLICATION_RESERVED designation.
> +	 */
> +	E820_TYPE_APPLICATION_RESERVED	= 0xefffffff,
> +
>  	/*
>  	 * Reserved RAM used by the kernel itself if
>  	 * CONFIG_INTEL_TXT=y is enabled, memory of this type
> diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
> index 7d52378e376a..4f80254e0541 100644
> --- a/arch/x86/include/asm/efi.h
> +++ b/arch/x86/include/asm/efi.h
> @@ -141,6 +141,19 @@ extern void efi_switch_mm(struct mm_struct *mm);
>  extern void efi_recover_from_page_fault(unsigned long phys_addr);
>  extern void efi_free_boot_services(void);
>  
> +#ifdef CONFIG_EFI_APPLICATION_RESERVED
> +static inline bool is_efi_application_reserved(efi_memory_desc_t *md)
> +{
> +	return md->type == EFI_CONVENTIONAL_MEMORY
> +		&& (md->attribute & EFI_MEMORY_SP);
> +}
> +#else
> +static inline bool is_efi_application_reserved(efi_memory_desc_t *md)
> +{
> +	return false;
> +}
> +#endif
> +
>  struct efi_setup_data {
>  	u64 fw_vendor;
>  	u64 runtime;
> @@ -244,6 +257,7 @@ extern bool efi_reboot_required(void);
>  
>  extern void efi_find_mirror(void);
>  extern void efi_reserve_boot_services(void);
> +extern void __init efi_find_application_reserved(void);
>  #else
>  static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
>  static inline bool efi_reboot_required(void)
> @@ -256,6 +270,9 @@ static inline void efi_find_mirror(void)
>  static inline void efi_reserve_boot_services(void)
>  {
>  }
> +static inline void __init efi_find_application_reserved(void)
> +{
> +}
>  #endif /* CONFIG_EFI */
>  
>  #endif /* _ASM_X86_EFI_H */
> diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
> index 8f32e705a980..c5b91c2d0661 100644
> --- a/arch/x86/kernel/e820.c
> +++ b/arch/x86/kernel/e820.c
> @@ -189,6 +189,7 @@ static void __init e820_print_type(enum e820_type type)
>  	switch (type) {
>  	case E820_TYPE_RAM:		/* Fall through: */
>  	case E820_TYPE_RESERVED_KERN:	pr_cont("usable");			break;
> +	case E820_TYPE_APPLICATION_RESERVED: pr_cont("application reserved");	break;
>  	case E820_TYPE_RESERVED:	pr_cont("reserved");			break;
>  	case E820_TYPE_ACPI:		pr_cont("ACPI data");			break;
>  	case E820_TYPE_NVS:		pr_cont("ACPI NVS");			break;
> @@ -1036,6 +1037,7 @@ static const char *__init e820_type_to_string(struct e820_entry *entry)
>  	case E820_TYPE_UNUSABLE:	return "Unusable memory";
>  	case E820_TYPE_PRAM:		return "Persistent Memory (legacy)";
>  	case E820_TYPE_PMEM:		return "Persistent Memory";
> +	case E820_TYPE_APPLICATION_RESERVED: return "Application Reserved";
>  	case E820_TYPE_RESERVED:	return "Reserved";
>  	default:			return "Unknown E820 type";
>  	}
> @@ -1051,6 +1053,7 @@ static unsigned long __init e820_type_to_iomem_type(struct e820_entry *entry)
>  	case E820_TYPE_UNUSABLE:	/* Fall-through: */
>  	case E820_TYPE_PRAM:		/* Fall-through: */
>  	case E820_TYPE_PMEM:		/* Fall-through: */
> +	case E820_TYPE_APPLICATION_RESERVED: /* Fall-through: */
>  	case E820_TYPE_RESERVED:	/* Fall-through: */
>  	default:			return IORESOURCE_MEM;
>  	}
> @@ -1063,6 +1066,7 @@ static unsigned long __init e820_type_to_iores_desc(struct e820_entry *entry)
>  	case E820_TYPE_NVS:		return IORES_DESC_ACPI_NV_STORAGE;
>  	case E820_TYPE_PMEM:		return IORES_DESC_PERSISTENT_MEMORY;
>  	case E820_TYPE_PRAM:		return IORES_DESC_PERSISTENT_MEMORY_LEGACY;
> +	case E820_TYPE_APPLICATION_RESERVED: return IORES_DESC_APPLICATION_RESERVED;
>  	case E820_TYPE_RESERVED_KERN:	/* Fall-through: */
>  	case E820_TYPE_RAM:		/* Fall-through: */
>  	case E820_TYPE_UNUSABLE:	/* Fall-through: */
> @@ -1078,13 +1082,14 @@ static bool __init do_mark_busy(enum e820_type type, struct resource *res)
>  		return true;
>  
>  	/*
> -	 * Treat persistent memory like device memory, i.e. reserve it
> -	 * for exclusive use of a driver
> +	 * Treat persistent memory and other special memory ranges like
> +	 * device memory, i.e. reserve it for exclusive use of a driver
>  	 */
>  	switch (type) {
>  	case E820_TYPE_RESERVED:
>  	case E820_TYPE_PRAM:
>  	case E820_TYPE_PMEM:
> +	case E820_TYPE_APPLICATION_RESERVED:
>  		return false;
>  	case E820_TYPE_RESERVED_KERN:
>  	case E820_TYPE_RAM:
> @@ -1285,6 +1290,9 @@ void __init e820__memblock_setup(void)
>  		if (end != (resource_size_t)end)
>  			continue;
>  
> +		if (entry->type == E820_TYPE_APPLICATION_RESERVED)
> +			memblock_reserve(entry->addr, entry->size);
> +
>  		if (entry->type != E820_TYPE_RAM && entry->type != E820_TYPE_RESERVED_KERN)
>  			continue;
>  
> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
> index b68fd57a8d26..3b9001b7c951 100644
> --- a/arch/x86/kernel/setup.c
> +++ b/arch/x86/kernel/setup.c
> @@ -1104,6 +1104,7 @@ void __init setup_arch(char **cmdline_p)
>  
>  	memblock_set_current_limit(ISA_END_ADDRESS);
>  
> +	efi_find_application_reserved();
>  	e820__memblock_setup();
>  
>  	reserve_bios_regions();
> diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
> index 4e8458b1ca30..4b4a9eb6d2c9 100644
> --- a/arch/x86/platform/efi/efi.c
> +++ b/arch/x86/platform/efi/efi.c
> @@ -126,10 +126,18 @@ void __init efi_find_mirror(void)
>   * more than the max 128 entries that can fit in the e820 legacy
>   * (zeropage) memory map.
>   */
> +enum add_efi_mode {
> +	ADD_EFI_ALL,
> +	ADD_EFI_APPLICATION_RESERVED,
> +};

This enum rather separates the above comment from the function which
it describes. Perhaps reorganize or make the comment include
the function name so it's clear what 'Tell the kernel about...'
refers to.

>  
> -static void __init do_add_efi_memmap(void)
> +static void __init do_add_efi_memmap(enum add_efi_mode mode)

The mode parameter is somewhat confusing.  Perhaps some docs?

>  {
>  	efi_memory_desc_t *md;
> +	int add = 0;
> +
> +	if (!efi_enabled(EFI_MEMMAP))
> +		return;
>  
>  	for_each_efi_memory_desc(md) {
>  		unsigned long long start = md->phys_addr;
> @@ -142,7 +150,9 @@ static void __init do_add_efi_memmap(void)
>  		case EFI_BOOT_SERVICES_CODE:
>  		case EFI_BOOT_SERVICES_DATA:
>  		case EFI_CONVENTIONAL_MEMORY:
> -			if (md->attribute & EFI_MEMORY_WB)
> +			if (is_efi_application_reserved(md))
> +				e820_type = E820_TYPE_APPLICATION_RESERVED;
> +			else if (md->attribute & EFI_MEMORY_WB)
>  				e820_type = E820_TYPE_RAM;
>  			else
>  				e820_type = E820_TYPE_RESERVED;
> @@ -168,9 +178,22 @@ static void __init do_add_efi_memmap(void)
>  			e820_type = E820_TYPE_RESERVED;
>  			break;
>  		}
> +
> +		if (e820_type == E820_TYPE_APPLICATION_RESERVED)
> +			/* always add E820_TYPE_APPLICATION_RESERVED */;
> +		else if (mode != ADD_EFI_APPLICATION_RESERVED)
> +			continue;
> +
> +		add++;
>  		e820__range_add(start, size, e820_type);
>  	}
> -	e820__update_table(e820_table);
> +	if (add)

> +		e820__update_table(e820_table);
> +}
> +
> +void __init efi_find_application_reserved(void)
> +{
> +	do_add_efi_memmap(ADD_EFI_APPLICATION_RESERVED);
>  }
>  
>  int __init efi_memblock_x86_reserve_range(void)
> @@ -203,7 +226,7 @@ int __init efi_memblock_x86_reserve_range(void)
>  		return rv;
>  
>  	if (add_efi_memmap)
> -		do_add_efi_memmap();
> +		do_add_efi_memmap(ADD_EFI_ALL);
>  
>  	WARN(efi.memmap.desc_version != 1,
>  	     "Unexpected EFI_MEMORY_DESCRIPTOR version %ld",
> @@ -756,6 +779,12 @@ static bool should_map_region(efi_memory_desc_t *md)
>  	if (IS_ENABLED(CONFIG_X86_32))
>  		return false;
>  
> +	/*
> +	 * Specific purpose memory is reserved by default.
> +	 */
This file is pretty consistent on comment syntax with single line comments as.
/* Specific purpose memory is reserved by default. */

> +	if (is_efi_application_reserved(md))
> +		return false;
> +
>  	/*
>  	 * Map all of RAM so that we can access arguments in the 1:1
>  	 * mapping when making EFI runtime calls.
> diff --git a/include/linux/ioport.h b/include/linux/ioport.h
> index da0ebaec25f0..2d79841ee9b9 100644
> --- a/include/linux/ioport.h
> +++ b/include/linux/ioport.h
> @@ -133,6 +133,7 @@ enum {
>  	IORES_DESC_PERSISTENT_MEMORY_LEGACY	= 5,
>  	IORES_DESC_DEVICE_PRIVATE_MEMORY	= 6,
>  	IORES_DESC_DEVICE_PUBLIC_MEMORY		= 7,
> +	IORES_DESC_APPLICATION_RESERVED		= 8,
>  };
>  
>  /* helpers to define resources */
> 



^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v4 08/10] device-dax: Add a driver for "hmem" devices
  2019-06-24 18:20 ` [PATCH v4 08/10] device-dax: Add a driver for "hmem" devices Dan Williams
@ 2019-06-25 15:37   ` Jonathan Cameron
  2019-06-25 20:07     ` Dan Williams
  0 siblings, 1 reply; 21+ messages in thread
From: Jonathan Cameron @ 2019-06-25 15:37 UTC (permalink / raw)
  To: Dan Williams
  Cc: x86, Vishal Verma, Keith Busch, Dave Jiang, kbuild test robot,
	Dave Hansen, peterz, ard.biesheuvel, tglx, linux-acpi,
	linux-nvdimm, linux-kernel

On Mon, 24 Jun 2019 11:20:16 -0700
Dan Williams <dan.j.williams@intel.com> wrote:

> Platform firmware like EFI/ACPI may publish "hmem" platform devices.
> Such a device is a performance differentiated memory range likely
> reserved for an application specific use case. The driver gives access
> to 100% of the capacity via a device-dax mmap instance by default.
> 
> However, if over-subscription and other kernel memory management is
> desired the resulting dax device can be assigned to the core-mm via the
> kmem driver.
> 
> This consumes "hmem" devices the producer of "hmem" devices is saved for
> a follow-on patch so that it can reference the new CONFIG_DEV_DAX_HMEM
> symbol to gate performing the enumeration work.
> 
> Cc: Vishal Verma <vishal.l.verma@intel.com>
> Cc: Keith Busch <keith.busch@intel.com>
> Cc: Dave Jiang <dave.jiang@intel.com>
> Reported-by: kbuild test robot <lkp@intel.com>
> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
No need to have a remove function at all.  Otherwise this looks good to me.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

> ---
>  drivers/dax/Kconfig    |   27 +++++++++++++++++++----
>  drivers/dax/Makefile   |    2 ++
>  drivers/dax/hmem.c     |   57 ++++++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/ioport.h |    4 +++
>  4 files changed, 85 insertions(+), 5 deletions(-)
>  create mode 100644 drivers/dax/hmem.c
> 
> diff --git a/drivers/dax/Kconfig b/drivers/dax/Kconfig
> index f33c73e4af41..1a59ef86f148 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_APPLICATION_RESERVED
> +	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/hmem.c b/drivers/dax/hmem.c
> new file mode 100644
> index 000000000000..62f9e3c80e21
> --- /dev/null
> +++ b/drivers/dax/hmem.c
> @@ -0,0 +1,57 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#include <linux/platform_device.h>
> +#include <linux/ioport.h>
> +#include <linux/module.h>
> +#include <linux/pfn_t.h>
> +#include "bus.h"
> +
> +static int dax_hmem_probe(struct platform_device *pdev)
> +{
> +	struct dev_pagemap pgmap = { NULL };
> +	struct device *dev = &pdev->dev;
> +	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;
> +	pgmap.dev = dev;
> +	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;

Why have a remove at all?  driver/base/platform.c has
the appropriate protections to allow you to not provide one.
If you want the comment, just put it after .probe =
below.

> +}
> +
> +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");
> diff --git a/include/linux/ioport.h b/include/linux/ioport.h
> index 72ea690b35a4..0c529c8f8027 100644
> --- a/include/linux/ioport.h
> +++ b/include/linux/ioport.h
> @@ -294,6 +294,10 @@ static inline bool resource_overlaps(struct resource *r1, struct resource *r2)
>  }
>  
>  #ifdef CONFIG_MEMREGION
> +struct memregion_info {
> +	int target_node;
> +};
> +
>  extern struct ida memregion_ids;
>  static inline int memregion_alloc(gfp_t gfp)
>  {
> 



^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v4 10/10] acpi/numa/hmat: Register "specific purpose" memory as an "hmem" device
  2019-06-24 18:20 ` [PATCH v4 10/10] acpi/numa/hmat: Register "specific purpose" memory as an "hmem" device Dan Williams
@ 2019-06-25 15:58   ` Jonathan Cameron
  2019-07-03 11:17   ` Rafael J. Wysocki
  1 sibling, 0 replies; 21+ messages in thread
From: Jonathan Cameron @ 2019-06-25 15:58 UTC (permalink / raw)
  To: Dan Williams
  Cc: x86, Len Brown, Keith Busch, Rafael J. Wysocki, Vishal Verma,
	Dave Hansen, peterz, ard.biesheuvel, tglx, linux-acpi,
	linux-nvdimm, linux-kernel

On Mon, 24 Jun 2019 11:20:26 -0700
Dan Williams <dan.j.williams@intel.com> wrote:

> Memory that has been tagged EFI_MEMORY_SP, and has performance
> properties described by the ACPI HMAT is expected to have an application
> specific consumer.
> 
> Those consumers may want 100% of the memory capacity to be reserved from
> any usage by the kernel. By default, with this enabling, a platform
> device is created to represent this differentiated resource.
> 
> The device-dax "hmem" driver claims these devices by default and
> provides an mmap interface for the target application.  If the
> administrator prefers, the hmem resource range can be made available to
> the core-mm via the device-dax hotplug facility, kmem, to online the
> memory with its own numa node.
> 
> This was tested with an emulated HMAT produced by qemu (with the pending
> HMAT enabling patches), and "efi_fake_mem=8G@9G:0x40000" on the kernel
> command line to mark the memory ranges associated with node2 and node3
> as EFI_MEMORY_SP.
> 
> qemu numa configuration options:
> 
> -numa node,mem=4G,cpus=0-19,nodeid=0
> -numa node,mem=4G,cpus=20-39,nodeid=1
> -numa node,mem=4G,nodeid=2
> -numa node,mem=4G,nodeid=3
> -numa dist,src=0,dst=0,val=10
> -numa dist,src=0,dst=1,val=21
> -numa dist,src=0,dst=2,val=21
> -numa dist,src=0,dst=3,val=21
> -numa dist,src=1,dst=0,val=21
> -numa dist,src=1,dst=1,val=10
> -numa dist,src=1,dst=2,val=21
> -numa dist,src=1,dst=3,val=21
> -numa dist,src=2,dst=0,val=21
> -numa dist,src=2,dst=1,val=21
> -numa dist,src=2,dst=2,val=10
> -numa dist,src=2,dst=3,val=21
> -numa dist,src=3,dst=0,val=21
> -numa dist,src=3,dst=1,val=21
> -numa dist,src=3,dst=2,val=21
> -numa dist,src=3,dst=3,val=10
> -numa hmat-lb,initiator=0,target=0,hierarchy=memory,data-type=access-latency,base-lat=10,latency=5
> -numa hmat-lb,initiator=0,target=0,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=5
> -numa hmat-lb,initiator=0,target=1,hierarchy=memory,data-type=access-latency,base-lat=10,latency=10
> -numa hmat-lb,initiator=0,target=1,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=10
> -numa hmat-lb,initiator=0,target=2,hierarchy=memory,data-type=access-latency,base-lat=10,latency=15
> -numa hmat-lb,initiator=0,target=2,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=15
> -numa hmat-lb,initiator=0,target=3,hierarchy=memory,data-type=access-latency,base-lat=10,latency=20
> -numa hmat-lb,initiator=0,target=3,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=20
> -numa hmat-lb,initiator=1,target=0,hierarchy=memory,data-type=access-latency,base-lat=10,latency=10
> -numa hmat-lb,initiator=1,target=0,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=10
> -numa hmat-lb,initiator=1,target=1,hierarchy=memory,data-type=access-latency,base-lat=10,latency=5
> -numa hmat-lb,initiator=1,target=1,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=5
> -numa hmat-lb,initiator=1,target=2,hierarchy=memory,data-type=access-latency,base-lat=10,latency=15
> -numa hmat-lb,initiator=1,target=2,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=15
> -numa hmat-lb,initiator=1,target=3,hierarchy=memory,data-type=access-latency,base-lat=10,latency=20
> -numa hmat-lb,initiator=1,target=3,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=20
> 
> Result:
> 
> # daxctl list -RDu
> [
>   {
>     "path":"\/platform\/hmem.1",
>     "id":1,
>     "size":"4.00 GiB (4.29 GB)",
>     "align":2097152,
>     "devices":[
>       {
>         "chardev":"dax1.0",
>         "size":"4.00 GiB (4.29 GB)"
>       }
>     ]
>   },
>   {
>     "path":"\/platform\/hmem.0",
>     "id":0,
>     "size":"4.00 GiB (4.29 GB)",
>     "align":2097152,
>     "devices":[
>       {
>         "chardev":"dax0.0",
>         "size":"4.00 GiB (4.29 GB)"
>       }
>     ]
>   }
> ]
> 
> # cat /proc/iomem
> [..]
> 240000000-43fffffff : Application Reserved
>   240000000-33fffffff : hmem.0
>     240000000-33fffffff : dax0.0
>   340000000-43fffffff : hmem.1
>     340000000-43fffffff : dax1.0
> 
> Cc: Len Brown <lenb@kernel.org>
> Cc: Keith Busch <keith.busch@intel.com>
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Cc: Vishal Verma <vishal.l.verma@intel.com>
> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Looks good to me.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

I like the approach of this patch set in general as it gives the flexibility to
the administrator of a given system.

Jonathan

> ---
>  drivers/acpi/numa/Kconfig |    1 
>  drivers/acpi/numa/hmat.c  |  132 +++++++++++++++++++++++++++++++++++++++++----
>  2 files changed, 122 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/acpi/numa/Kconfig b/drivers/acpi/numa/Kconfig
> index d14582387ed0..c1be746e111a 100644
> --- a/drivers/acpi/numa/Kconfig
> +++ b/drivers/acpi/numa/Kconfig
> @@ -8,6 +8,7 @@ config ACPI_HMAT
>  	bool "ACPI Heterogeneous Memory Attribute Table Support"
>  	depends on ACPI_NUMA
>  	select HMEM_REPORTING
> +	select MEMREGION
>  	help
>  	 If set, this option has the kernel parse and report the
>  	 platform's ACPI HMAT (Heterogeneous Memory Attributes Table),
> diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c
> index 1d329c4af3bf..622c5feb3aa0 100644
> --- a/drivers/acpi/numa/hmat.c
> +++ b/drivers/acpi/numa/hmat.c
> @@ -8,11 +8,16 @@
>   * the applicable attributes with the node's interfaces.
>   */
>  
> +#define pr_fmt(fmt) "acpi/hmat: " fmt
> +#define dev_fmt(fmt) "acpi/hmat: " fmt
> +
>  #include <linux/acpi.h>
>  #include <linux/bitops.h>
>  #include <linux/device.h>
>  #include <linux/init.h>
>  #include <linux/list.h>
> +#include <linux/mm.h>
> +#include <linux/platform_device.h>
>  #include <linux/list_sort.h>
>  #include <linux/node.h>
>  #include <linux/sysfs.h>
> @@ -40,6 +45,7 @@ struct memory_target {
>  	struct list_head node;
>  	unsigned int memory_pxm;
>  	unsigned int processor_pxm;
> +	struct resource memregions;
>  	struct node_hmem_attrs hmem_attrs;
>  };
>  
> @@ -92,21 +98,35 @@ static __init void alloc_memory_initiator(unsigned int cpu_pxm)
>  	list_add_tail(&initiator->node, &initiators);
>  }
>  
> -static __init void alloc_memory_target(unsigned int mem_pxm)
> +static __init void alloc_memory_target(unsigned int mem_pxm,
> +		resource_size_t start, resource_size_t len)
>  {
>  	struct memory_target *target;
>  
>  	target = find_mem_target(mem_pxm);
> -	if (target)
> -		return;
> -
> -	target = kzalloc(sizeof(*target), GFP_KERNEL);
> -	if (!target)
> -		return;
> +	if (!target) {
> +		target = kzalloc(sizeof(*target), GFP_KERNEL);
> +		if (!target)
> +			return;
> +		target->memory_pxm = mem_pxm;
> +		target->processor_pxm = PXM_INVAL;
> +		target->memregions = (struct resource) {
> +			.name	= "ACPI mem",
> +			.start	= 0,
> +			.end	= -1,
> +			.flags	= IORESOURCE_MEM,
> +		};
> +		list_add_tail(&target->node, &targets);
> +	}
>  
> -	target->memory_pxm = mem_pxm;
> -	target->processor_pxm = PXM_INVAL;
> -	list_add_tail(&target->node, &targets);
> +	/*
> +	 * There are potentially multiple ranges per PXM, so record each
> +	 * in the per-target memregions resource tree.
> +	 */
> +	if (!__request_region(&target->memregions, start, len, "memory target",
> +				IORESOURCE_MEM))
> +		pr_warn("failed to reserve %#llx - %#llx in pxm: %d\n",
> +				start, start + len, mem_pxm);
>  }
>  
>  static __init const char *hmat_data_type(u8 type)
> @@ -428,7 +448,7 @@ static __init int srat_parse_mem_affinity(union acpi_subtable_headers *header,
>  		return -EINVAL;
>  	if (!(ma->flags & ACPI_SRAT_MEM_ENABLED))
>  		return 0;
> -	alloc_memory_target(ma->proximity_domain);
> +	alloc_memory_target(ma->proximity_domain, ma->base_address, ma->length);
>  	return 0;
>  }
>  
> @@ -580,6 +600,81 @@ static __init void hmat_register_target_perf(struct memory_target *target)
>  	node_set_perf_attrs(mem_nid, &target->hmem_attrs, 0);
>  }
>  
> +static __init void hmat_register_target_device(struct memory_target *target,
> +		struct resource *r)
> +{
> +	/* define a clean / non-busy resource for the platform device */
> +	struct resource res = {
> +		.start = r->start,
> +		.end = r->end,
> +		.flags = IORESOURCE_MEM,
> +	};
> +	struct platform_device *pdev;
> +	struct memregion_info info;
> +	int rc, id;
> +
> +	rc = region_intersects(res.start, resource_size(&res), IORESOURCE_MEM,
> +			IORES_DESC_APPLICATION_RESERVED);
> +	if (rc != REGION_INTERSECTS)
> +		return;
> +
> +	id = memregion_alloc(GFP_KERNEL);
> +	if (id < 0) {
> +		pr_err("memregion allocation failure for %pr\n", &res);
> +		return;
> +	}
> +
> +	pdev = platform_device_alloc("hmem", id);
> +	if (!pdev) {
> +		pr_err("hmem device allocation failure for %pr\n", &res);
> +		goto out_pdev;
> +	}
> +
> +	pdev->dev.numa_node = acpi_map_pxm_to_online_node(target->memory_pxm);
> +	info = (struct memregion_info) {
> +		.target_node = acpi_map_pxm_to_node(target->memory_pxm),
> +	};
> +	rc = platform_device_add_data(pdev, &info, sizeof(info));
> +	if (rc < 0) {
> +		pr_err("hmem memregion_info allocation failure for %pr\n", &res);
> +		goto out_pdev;
> +	}
> +
> +	rc = platform_device_add_resources(pdev, &res, 1);
> +	if (rc < 0) {
> +		pr_err("hmem resource allocation failure for %pr\n", &res);
> +		goto out_resource;
> +	}
> +
> +	rc = platform_device_add(pdev);
> +	if (rc < 0) {
> +		dev_err(&pdev->dev, "device add failed for %pr\n", &res);
> +		goto out_resource;
> +	}
> +
> +	return;
> +
> +out_resource:
> +	put_device(&pdev->dev);
> +out_pdev:
> +	memregion_free(id);
> +}
> +
> +static __init void hmat_register_target_devices(struct memory_target *target)
> +{
> +	struct resource *res;
> +
> +	/*
> +	 * Do not bother creating devices if no driver is available to
> +	 * consume them.
> +	 */
> +	if (!IS_ENABLED(CONFIG_DEV_DAX_HMEM))
> +		return;
> +
> +	for (res = target->memregions.child; res; res = res->sibling)
> +		hmat_register_target_device(target, res);
> +}
> +
>  static __init void hmat_register_targets(void)
>  {
>  	struct memory_target *target;
> @@ -587,6 +682,12 @@ static __init void hmat_register_targets(void)
>  	list_for_each_entry(target, &targets, node) {
>  		int nid = pxm_to_node(target->memory_pxm);
>  
> +		/*
> +		 * Devices may belong to either an offline or online
> +		 * node, so unconditionally add them.
> +		 */
> +		hmat_register_target_devices(target);
> +
>  		/*
>  		 * Skip offline nodes. This can happen when memory
>  		 * marked EFI_MEMORY_SP, "specific purpose", is applied
> @@ -608,7 +709,16 @@ static __init void hmat_free_structures(void)
>  	struct memory_initiator *initiator, *inext;
>  
>  	list_for_each_entry_safe(target, tnext, &targets, node) {
> +		struct resource *res, *res_next;
> +
>  		list_del(&target->node);
> +		res = target->memregions.child;
> +		while (res) {
> +			res_next = res->sibling;
> +			__release_region(&target->memregions, res->start,
> +					resource_size(res));
> +			res = res_next;
> +		}
>  		kfree(target);
>  	}
>  
> 



^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v4 01/10] acpi/numa: Establish a new drivers/acpi/numa/ directory
  2019-06-25 14:59   ` Jonathan Cameron
@ 2019-06-25 16:02     ` Dan Williams
  0 siblings, 0 replies; 21+ messages in thread
From: Dan Williams @ 2019-06-25 16:02 UTC (permalink / raw)
  To: Jonathan Cameron
  Cc: X86 ML, Len Brown, Keith Busch, Rafael J. Wysocki, Dave Hansen,
	Peter Zijlstra, Vishal L Verma, Ard Biesheuvel, Thomas Gleixner,
	Linux ACPI, linux-nvdimm, Linux Kernel Mailing List

On Tue, Jun 25, 2019 at 8:01 AM Jonathan Cameron
<jonathan.cameron@huawei.com> wrote:
>
> On Mon, 24 Jun 2019 11:19:32 -0700
> Dan Williams <dan.j.williams@intel.com> wrote:
>
> > Currently hmat.c lives under an "hmat" directory which does not enhance
> > the description of the file. The initial motivation for giving hmat.c
> > its own directory was to delineate it as mm functionality in contrast to
> > ACPI device driver functionality.
> >
> > As ACPI continues to play an increasing role in conveying
> > memory location and performance topology information to the OS take the
> > opportunity to co-locate these NUMA relevant tables in a combined
> > directory.
> >
> > numa.c is renamed to srat.c and moved to drivers/acpi/numa/ along with
> > hmat.c.
>
> Hi Dan,
>
> srat.c now includes processing for the slit table which is a bit odd.
>
> Now we could split this up in to a top level numa.c and then
> srat.c, slit.c and hmat.c....
>
> Does feel rather silly though.  Perhaps better to just leave it as
> numa.c?

The srat and slit tables go hand in hand, I'm not too bothered by the
fact that the slit table does not get top billing with its own source
file name.

The "numa" term is already in the path name, and calling numa.c leaves
out hmat details which are also "numa".

> I don't really feel strongly about this though.

Understood, I just did not see the justification for HMAT being off in
its own directory when it is a direct extension of the existing
ACPI_NUMA functionality, the other renames were my best effort to
rationalize the code organization.

^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v4 08/10] device-dax: Add a driver for "hmem" devices
  2019-06-25 15:37   ` Jonathan Cameron
@ 2019-06-25 20:07     ` Dan Williams
  0 siblings, 0 replies; 21+ messages in thread
From: Dan Williams @ 2019-06-25 20:07 UTC (permalink / raw)
  To: Jonathan Cameron
  Cc: X86 ML, Vishal Verma, Keith Busch, Dave Jiang, kbuild test robot,
	Dave Hansen, Peter Zijlstra, Ard Biesheuvel, Thomas Gleixner,
	Linux ACPI, linux-nvdimm, Linux Kernel Mailing List

On Tue, Jun 25, 2019 at 8:39 AM Jonathan Cameron
<jonathan.cameron@huawei.com> wrote:
>
> On Mon, 24 Jun 2019 11:20:16 -0700
> Dan Williams <dan.j.williams@intel.com> wrote:
>
> > Platform firmware like EFI/ACPI may publish "hmem" platform devices.
> > Such a device is a performance differentiated memory range likely
> > reserved for an application specific use case. The driver gives access
> > to 100% of the capacity via a device-dax mmap instance by default.
> >
> > However, if over-subscription and other kernel memory management is
> > desired the resulting dax device can be assigned to the core-mm via the
> > kmem driver.
> >
> > This consumes "hmem" devices the producer of "hmem" devices is saved for
> > a follow-on patch so that it can reference the new CONFIG_DEV_DAX_HMEM
> > symbol to gate performing the enumeration work.
> >
> > Cc: Vishal Verma <vishal.l.verma@intel.com>
> > Cc: Keith Busch <keith.busch@intel.com>
> > Cc: Dave Jiang <dave.jiang@intel.com>
> > Reported-by: kbuild test robot <lkp@intel.com>
> > Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
> > Signed-off-by: Dan Williams <dan.j.williams@intel.com>
> No need to have a remove function at all.  Otherwise this looks good to me.
>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
>
> > ---
> >  drivers/dax/Kconfig    |   27 +++++++++++++++++++----
> >  drivers/dax/Makefile   |    2 ++
> >  drivers/dax/hmem.c     |   57 ++++++++++++++++++++++++++++++++++++++++++++++++
> >  include/linux/ioport.h |    4 +++
> >  4 files changed, 85 insertions(+), 5 deletions(-)
> >  create mode 100644 drivers/dax/hmem.c
> >
> > diff --git a/drivers/dax/Kconfig b/drivers/dax/Kconfig
> > index f33c73e4af41..1a59ef86f148 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_APPLICATION_RESERVED
> > +     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/hmem.c b/drivers/dax/hmem.c
> > new file mode 100644
> > index 000000000000..62f9e3c80e21
> > --- /dev/null
> > +++ b/drivers/dax/hmem.c
> > @@ -0,0 +1,57 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +#include <linux/platform_device.h>
> > +#include <linux/ioport.h>
> > +#include <linux/module.h>
> > +#include <linux/pfn_t.h>
> > +#include "bus.h"
> > +
> > +static int dax_hmem_probe(struct platform_device *pdev)
> > +{
> > +     struct dev_pagemap pgmap = { NULL };
> > +     struct device *dev = &pdev->dev;
> > +     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;
> > +     pgmap.dev = dev;
> > +     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;
>
> Why have a remove at all?  driver/base/platform.c has
> the appropriate protections to allow you to not provide one.
> If you want the comment, just put it after .probe =
> below.

True, that's a good cleanup.

^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v4 01/10] acpi/numa: Establish a new drivers/acpi/numa/ directory
  2019-06-24 18:19 ` [PATCH v4 01/10] acpi/numa: Establish a new drivers/acpi/numa/ directory Dan Williams
  2019-06-25 14:59   ` Jonathan Cameron
@ 2019-07-03 11:09   ` Rafael J. Wysocki
  1 sibling, 0 replies; 21+ messages in thread
From: Rafael J. Wysocki @ 2019-07-03 11:09 UTC (permalink / raw)
  To: Dan Williams
  Cc: the arch/x86 maintainers, Len Brown, Keith Busch,
	Rafael J. Wysocki, Dave Hansen, Peter Zijlstra, Vishal Verma,
	Ard Biesheuvel, Thomas Gleixner, ACPI Devel Maling List,
	linux-nvdimm, Linux Kernel Mailing List

On Mon, Jun 24, 2019 at 8:33 PM Dan Williams <dan.j.williams@intel.com> wrote:
>
> Currently hmat.c lives under an "hmat" directory which does not enhance
> the description of the file. The initial motivation for giving hmat.c
> its own directory was to delineate it as mm functionality in contrast to
> ACPI device driver functionality.
>
> As ACPI continues to play an increasing role in conveying
> memory location and performance topology information to the OS take the
> opportunity to co-locate these NUMA relevant tables in a combined
> directory.
>
> numa.c is renamed to srat.c and moved to drivers/acpi/numa/ along with
> hmat.c.
>
> Cc: Len Brown <lenb@kernel.org>
> Cc: Keith Busch <keith.busch@intel.com>
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

> ---
>  drivers/acpi/Kconfig       |    9 +--------
>  drivers/acpi/Makefile      |    3 +--
>  drivers/acpi/hmat/Makefile |    2 --
>  drivers/acpi/numa/Kconfig  |    7 ++++++-
>  drivers/acpi/numa/Makefile |    3 +++
>  drivers/acpi/numa/hmat.c   |    0
>  drivers/acpi/numa/srat.c   |    0
>  7 files changed, 11 insertions(+), 13 deletions(-)
>  delete mode 100644 drivers/acpi/hmat/Makefile
>  rename drivers/acpi/{hmat/Kconfig => numa/Kconfig} (72%)
>  create mode 100644 drivers/acpi/numa/Makefile
>  rename drivers/acpi/{hmat/hmat.c => numa/hmat.c} (100%)
>  rename drivers/acpi/{numa.c => numa/srat.c} (100%)
>
> diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
> index 283ee94224c6..82c4a31c8701 100644
> --- a/drivers/acpi/Kconfig
> +++ b/drivers/acpi/Kconfig
> @@ -321,12 +321,6 @@ config ACPI_THERMAL
>           To compile this driver as a module, choose M here:
>           the module will be called thermal.
>
> -config ACPI_NUMA
> -       bool "NUMA support"
> -       depends on NUMA
> -       depends on (X86 || IA64 || ARM64)
> -       default y if IA64_GENERIC || IA64_SGI_SN2 || ARM64
> -
>  config ACPI_CUSTOM_DSDT_FILE
>         string "Custom DSDT Table file to include"
>         default ""
> @@ -475,8 +469,7 @@ config ACPI_REDUCED_HARDWARE_ONLY
>           If you are unsure what to do, do not enable this option.
>
>  source "drivers/acpi/nfit/Kconfig"
> -source "drivers/acpi/hmat/Kconfig"
> -
> +source "drivers/acpi/numa/Kconfig"
>  source "drivers/acpi/apei/Kconfig"
>  source "drivers/acpi/dptf/Kconfig"
>
> diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
> index 5d361e4e3405..f08a661274e8 100644
> --- a/drivers/acpi/Makefile
> +++ b/drivers/acpi/Makefile
> @@ -55,7 +55,6 @@ acpi-$(CONFIG_X86)            += acpi_cmos_rtc.o
>  acpi-$(CONFIG_X86)             += x86/apple.o
>  acpi-$(CONFIG_X86)             += x86/utils.o
>  acpi-$(CONFIG_DEBUG_FS)                += debugfs.o
> -acpi-$(CONFIG_ACPI_NUMA)       += numa.o
>  acpi-$(CONFIG_ACPI_PROCFS_POWER) += cm_sbs.o
>  acpi-y                         += acpi_lpat.o
>  acpi-$(CONFIG_ACPI_LPIT)       += acpi_lpit.o
> @@ -80,7 +79,7 @@ obj-$(CONFIG_ACPI_PROCESSOR)  += processor.o
>  obj-$(CONFIG_ACPI)             += container.o
>  obj-$(CONFIG_ACPI_THERMAL)     += thermal.o
>  obj-$(CONFIG_ACPI_NFIT)                += nfit/
> -obj-$(CONFIG_ACPI_HMAT)                += hmat/
> +obj-$(CONFIG_ACPI_NUMA)                += numa/
>  obj-$(CONFIG_ACPI)             += acpi_memhotplug.o
>  obj-$(CONFIG_ACPI_HOTPLUG_IOAPIC) += ioapic.o
>  obj-$(CONFIG_ACPI_BATTERY)     += battery.o
> diff --git a/drivers/acpi/hmat/Makefile b/drivers/acpi/hmat/Makefile
> deleted file mode 100644
> index 1c20ef36a385..000000000000
> --- a/drivers/acpi/hmat/Makefile
> +++ /dev/null
> @@ -1,2 +0,0 @@
> -# SPDX-License-Identifier: GPL-2.0-only
> -obj-$(CONFIG_ACPI_HMAT) := hmat.o
> diff --git a/drivers/acpi/hmat/Kconfig b/drivers/acpi/numa/Kconfig
> similarity index 72%
> rename from drivers/acpi/hmat/Kconfig
> rename to drivers/acpi/numa/Kconfig
> index 95a29964dbea..d14582387ed0 100644
> --- a/drivers/acpi/hmat/Kconfig
> +++ b/drivers/acpi/numa/Kconfig
> @@ -1,4 +1,9 @@
> -# SPDX-License-Identifier: GPL-2.0
> +config ACPI_NUMA
> +       bool "NUMA support"
> +       depends on NUMA
> +       depends on (X86 || IA64 || ARM64)
> +       default y if IA64_GENERIC || IA64_SGI_SN2 || ARM64
> +
>  config ACPI_HMAT
>         bool "ACPI Heterogeneous Memory Attribute Table Support"
>         depends on ACPI_NUMA
> diff --git a/drivers/acpi/numa/Makefile b/drivers/acpi/numa/Makefile
> new file mode 100644
> index 000000000000..517a6c689a94
> --- /dev/null
> +++ b/drivers/acpi/numa/Makefile
> @@ -0,0 +1,3 @@
> +# SPDX-License-Identifier: GPL-2.0-only
> +obj-$(CONFIG_ACPI_NUMA) += srat.o
> +obj-$(CONFIG_ACPI_HMAT) += hmat.o
> diff --git a/drivers/acpi/hmat/hmat.c b/drivers/acpi/numa/hmat.c
> similarity index 100%
> rename from drivers/acpi/hmat/hmat.c
> rename to drivers/acpi/numa/hmat.c
> diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa/srat.c
> similarity index 100%
> rename from drivers/acpi/numa.c
> rename to drivers/acpi/numa/srat.c
>

^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v4 02/10] acpi/numa/hmat: Skip publishing target info for nodes with no online memory
  2019-06-24 18:19 ` [PATCH v4 02/10] acpi/numa/hmat: Skip publishing target info for nodes with no online memory Dan Williams
@ 2019-07-03 11:10   ` Rafael J. Wysocki
  0 siblings, 0 replies; 21+ messages in thread
From: Rafael J. Wysocki @ 2019-07-03 11:10 UTC (permalink / raw)
  To: Dan Williams
  Cc: the arch/x86 maintainers, Dave Hansen, Peter Zijlstra,
	Vishal Verma, Ard Biesheuvel, Thomas Gleixner,
	ACPI Devel Maling List, linux-nvdimm, Linux Kernel Mailing List

On Mon, Jun 24, 2019 at 8:33 PM Dan Williams <dan.j.williams@intel.com> wrote:
>
> There are multiple scenarios where the HMAT may contain information
> about proximity domains that are not currently online. Rather than fail
> to report any HMAT data just elide those offline domains.
>
> If and when those domains are later onlined they can be added to the
> HMEM reporting at that point.
>
> This was found while testing EFI_MEMORY_SP support which reserves
> "specific purpose" memory from the general allocation pool. If that
> reservation results in an empty numa-node then the node is not marked
> online leading a spurious:
>
>     "acpi/hmat: Ignoring HMAT: Invalid table"
>
> ...result for HMAT parsing.
>
> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

> ---
>  drivers/acpi/numa/hmat.c |   14 +++++++++++---
>  1 file changed, 11 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c
> index 96b7d39a97c6..2c220cb7b620 100644
> --- a/drivers/acpi/numa/hmat.c
> +++ b/drivers/acpi/numa/hmat.c
> @@ -96,9 +96,6 @@ static __init void alloc_memory_target(unsigned int mem_pxm)
>  {
>         struct memory_target *target;
>
> -       if (pxm_to_node(mem_pxm) == NUMA_NO_NODE)
> -               return;
> -
>         target = find_mem_target(mem_pxm);
>         if (target)
>                 return;
> @@ -588,6 +585,17 @@ static __init void hmat_register_targets(void)
>         struct memory_target *target;
>
>         list_for_each_entry(target, &targets, node) {
> +               int nid = pxm_to_node(target->memory_pxm);
> +
> +               /*
> +                * Skip offline nodes. This can happen when memory
> +                * marked EFI_MEMORY_SP, "specific purpose", is applied
> +                * to all the memory in a promixity domain leading to
> +                * the node being marked offline / unplugged, or if
> +                * memory-only "hotplug" node is offline.
> +                */
> +               if (nid == NUMA_NO_NODE || !node_online(nid))
> +                       continue;
>                 hmat_register_target_initiators(target);
>                 hmat_register_target_perf(target);
>         }
>

^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v4 09/10] acpi/numa/hmat: Register HMAT at device_initcall level
  2019-06-24 18:20 ` [PATCH v4 09/10] acpi/numa/hmat: Register HMAT at device_initcall level Dan Williams
@ 2019-07-03 11:12   ` Rafael J. Wysocki
  0 siblings, 0 replies; 21+ messages in thread
From: Rafael J. Wysocki @ 2019-07-03 11:12 UTC (permalink / raw)
  To: Dan Williams
  Cc: the arch/x86 maintainers, Rafael J. Wysocki, Len Brown,
	Keith Busch, Jonathan Cameron, Dave Hansen, Peter Zijlstra,
	Vishal Verma, Ard Biesheuvel, Thomas Gleixner,
	ACPI Devel Maling List, linux-nvdimm, Linux Kernel Mailing List

On Mon, Jun 24, 2019 at 8:34 PM Dan Williams <dan.j.williams@intel.com> wrote:
>
> In preparation for registering device-dax instances for accessing EFI
> specific-purpose memory, arrange for the HMAT registration to occur
> later in the init process. Critically HMAT initialization needs to occur
> after e820__reserve_resources_late() which is the point at which the
> iomem resource tree is populated with "Application Reserved"
> (IORES_DESC_APPLICATION_RESERVED). e820__reserve_resources_late()
> happens at subsys_initcall time.
>
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Cc: Len Brown <lenb@kernel.org>
> Cc: Keith Busch <keith.busch@intel.com>
> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

> ---
>  drivers/acpi/numa/hmat.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c
> index 2c220cb7b620..1d329c4af3bf 100644
> --- a/drivers/acpi/numa/hmat.c
> +++ b/drivers/acpi/numa/hmat.c
> @@ -671,4 +671,4 @@ static __init int hmat_init(void)
>         acpi_put_table(tbl);
>         return 0;
>  }
> -subsys_initcall(hmat_init);
> +device_initcall(hmat_init);
>

^ permalink raw reply	[flat|nested] 21+ messages in thread

* Re: [PATCH v4 10/10] acpi/numa/hmat: Register "specific purpose" memory as an "hmem" device
  2019-06-24 18:20 ` [PATCH v4 10/10] acpi/numa/hmat: Register "specific purpose" memory as an "hmem" device Dan Williams
  2019-06-25 15:58   ` Jonathan Cameron
@ 2019-07-03 11:17   ` Rafael J. Wysocki
  1 sibling, 0 replies; 21+ messages in thread
From: Rafael J. Wysocki @ 2019-07-03 11:17 UTC (permalink / raw)
  To: Dan Williams
  Cc: the arch/x86 maintainers, Len Brown, Keith Busch,
	Rafael J. Wysocki, Vishal Verma, Jonathan Cameron, Dave Hansen,
	Peter Zijlstra, Ard Biesheuvel, Thomas Gleixner,
	ACPI Devel Maling List, linux-nvdimm, Linux Kernel Mailing List

On Mon, Jun 24, 2019 at 8:34 PM Dan Williams <dan.j.williams@intel.com> wrote:
>
> Memory that has been tagged EFI_MEMORY_SP, and has performance
> properties described by the ACPI HMAT is expected to have an application
> specific consumer.
>
> Those consumers may want 100% of the memory capacity to be reserved from
> any usage by the kernel. By default, with this enabling, a platform
> device is created to represent this differentiated resource.
>
> The device-dax "hmem" driver claims these devices by default and
> provides an mmap interface for the target application.  If the
> administrator prefers, the hmem resource range can be made available to
> the core-mm via the device-dax hotplug facility, kmem, to online the
> memory with its own numa node.
>
> This was tested with an emulated HMAT produced by qemu (with the pending
> HMAT enabling patches), and "efi_fake_mem=8G@9G:0x40000" on the kernel
> command line to mark the memory ranges associated with node2 and node3
> as EFI_MEMORY_SP.
>
> qemu numa configuration options:
>
> -numa node,mem=4G,cpus=0-19,nodeid=0
> -numa node,mem=4G,cpus=20-39,nodeid=1
> -numa node,mem=4G,nodeid=2
> -numa node,mem=4G,nodeid=3
> -numa dist,src=0,dst=0,val=10
> -numa dist,src=0,dst=1,val=21
> -numa dist,src=0,dst=2,val=21
> -numa dist,src=0,dst=3,val=21
> -numa dist,src=1,dst=0,val=21
> -numa dist,src=1,dst=1,val=10
> -numa dist,src=1,dst=2,val=21
> -numa dist,src=1,dst=3,val=21
> -numa dist,src=2,dst=0,val=21
> -numa dist,src=2,dst=1,val=21
> -numa dist,src=2,dst=2,val=10
> -numa dist,src=2,dst=3,val=21
> -numa dist,src=3,dst=0,val=21
> -numa dist,src=3,dst=1,val=21
> -numa dist,src=3,dst=2,val=21
> -numa dist,src=3,dst=3,val=10
> -numa hmat-lb,initiator=0,target=0,hierarchy=memory,data-type=access-latency,base-lat=10,latency=5
> -numa hmat-lb,initiator=0,target=0,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=5
> -numa hmat-lb,initiator=0,target=1,hierarchy=memory,data-type=access-latency,base-lat=10,latency=10
> -numa hmat-lb,initiator=0,target=1,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=10
> -numa hmat-lb,initiator=0,target=2,hierarchy=memory,data-type=access-latency,base-lat=10,latency=15
> -numa hmat-lb,initiator=0,target=2,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=15
> -numa hmat-lb,initiator=0,target=3,hierarchy=memory,data-type=access-latency,base-lat=10,latency=20
> -numa hmat-lb,initiator=0,target=3,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=20
> -numa hmat-lb,initiator=1,target=0,hierarchy=memory,data-type=access-latency,base-lat=10,latency=10
> -numa hmat-lb,initiator=1,target=0,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=10
> -numa hmat-lb,initiator=1,target=1,hierarchy=memory,data-type=access-latency,base-lat=10,latency=5
> -numa hmat-lb,initiator=1,target=1,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=5
> -numa hmat-lb,initiator=1,target=2,hierarchy=memory,data-type=access-latency,base-lat=10,latency=15
> -numa hmat-lb,initiator=1,target=2,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=15
> -numa hmat-lb,initiator=1,target=3,hierarchy=memory,data-type=access-latency,base-lat=10,latency=20
> -numa hmat-lb,initiator=1,target=3,hierarchy=memory,data-type=access-bandwidth,base-bw=20,bandwidth=20
>
> Result:
>
> # daxctl list -RDu
> [
>   {
>     "path":"\/platform\/hmem.1",
>     "id":1,
>     "size":"4.00 GiB (4.29 GB)",
>     "align":2097152,
>     "devices":[
>       {
>         "chardev":"dax1.0",
>         "size":"4.00 GiB (4.29 GB)"
>       }
>     ]
>   },
>   {
>     "path":"\/platform\/hmem.0",
>     "id":0,
>     "size":"4.00 GiB (4.29 GB)",
>     "align":2097152,
>     "devices":[
>       {
>         "chardev":"dax0.0",
>         "size":"4.00 GiB (4.29 GB)"
>       }
>     ]
>   }
> ]
>
> # cat /proc/iomem
> [..]
> 240000000-43fffffff : Application Reserved
>   240000000-33fffffff : hmem.0
>     240000000-33fffffff : dax0.0
>   340000000-43fffffff : hmem.1
>     340000000-43fffffff : dax1.0
>
> Cc: Len Brown <lenb@kernel.org>
> Cc: Keith Busch <keith.busch@intel.com>
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Cc: Vishal Verma <vishal.l.verma@intel.com>
> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

> ---
>  drivers/acpi/numa/Kconfig |    1
>  drivers/acpi/numa/hmat.c  |  132 +++++++++++++++++++++++++++++++++++++++++----
>  2 files changed, 122 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/acpi/numa/Kconfig b/drivers/acpi/numa/Kconfig
> index d14582387ed0..c1be746e111a 100644
> --- a/drivers/acpi/numa/Kconfig
> +++ b/drivers/acpi/numa/Kconfig
> @@ -8,6 +8,7 @@ config ACPI_HMAT
>         bool "ACPI Heterogeneous Memory Attribute Table Support"
>         depends on ACPI_NUMA
>         select HMEM_REPORTING
> +       select MEMREGION
>         help
>          If set, this option has the kernel parse and report the
>          platform's ACPI HMAT (Heterogeneous Memory Attributes Table),
> diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c
> index 1d329c4af3bf..622c5feb3aa0 100644
> --- a/drivers/acpi/numa/hmat.c
> +++ b/drivers/acpi/numa/hmat.c
> @@ -8,11 +8,16 @@
>   * the applicable attributes with the node's interfaces.
>   */
>
> +#define pr_fmt(fmt) "acpi/hmat: " fmt
> +#define dev_fmt(fmt) "acpi/hmat: " fmt
> +
>  #include <linux/acpi.h>
>  #include <linux/bitops.h>
>  #include <linux/device.h>
>  #include <linux/init.h>
>  #include <linux/list.h>
> +#include <linux/mm.h>
> +#include <linux/platform_device.h>
>  #include <linux/list_sort.h>
>  #include <linux/node.h>
>  #include <linux/sysfs.h>
> @@ -40,6 +45,7 @@ struct memory_target {
>         struct list_head node;
>         unsigned int memory_pxm;
>         unsigned int processor_pxm;
> +       struct resource memregions;
>         struct node_hmem_attrs hmem_attrs;
>  };
>
> @@ -92,21 +98,35 @@ static __init void alloc_memory_initiator(unsigned int cpu_pxm)
>         list_add_tail(&initiator->node, &initiators);
>  }
>
> -static __init void alloc_memory_target(unsigned int mem_pxm)
> +static __init void alloc_memory_target(unsigned int mem_pxm,
> +               resource_size_t start, resource_size_t len)
>  {
>         struct memory_target *target;
>
>         target = find_mem_target(mem_pxm);
> -       if (target)
> -               return;
> -
> -       target = kzalloc(sizeof(*target), GFP_KERNEL);
> -       if (!target)
> -               return;
> +       if (!target) {
> +               target = kzalloc(sizeof(*target), GFP_KERNEL);
> +               if (!target)
> +                       return;
> +               target->memory_pxm = mem_pxm;
> +               target->processor_pxm = PXM_INVAL;
> +               target->memregions = (struct resource) {
> +                       .name   = "ACPI mem",
> +                       .start  = 0,
> +                       .end    = -1,
> +                       .flags  = IORESOURCE_MEM,
> +               };
> +               list_add_tail(&target->node, &targets);
> +       }
>
> -       target->memory_pxm = mem_pxm;
> -       target->processor_pxm = PXM_INVAL;
> -       list_add_tail(&target->node, &targets);
> +       /*
> +        * There are potentially multiple ranges per PXM, so record each
> +        * in the per-target memregions resource tree.
> +        */
> +       if (!__request_region(&target->memregions, start, len, "memory target",
> +                               IORESOURCE_MEM))
> +               pr_warn("failed to reserve %#llx - %#llx in pxm: %d\n",
> +                               start, start + len, mem_pxm);
>  }
>
>  static __init const char *hmat_data_type(u8 type)
> @@ -428,7 +448,7 @@ static __init int srat_parse_mem_affinity(union acpi_subtable_headers *header,
>                 return -EINVAL;
>         if (!(ma->flags & ACPI_SRAT_MEM_ENABLED))
>                 return 0;
> -       alloc_memory_target(ma->proximity_domain);
> +       alloc_memory_target(ma->proximity_domain, ma->base_address, ma->length);
>         return 0;
>  }
>
> @@ -580,6 +600,81 @@ static __init void hmat_register_target_perf(struct memory_target *target)
>         node_set_perf_attrs(mem_nid, &target->hmem_attrs, 0);
>  }
>
> +static __init void hmat_register_target_device(struct memory_target *target,
> +               struct resource *r)
> +{
> +       /* define a clean / non-busy resource for the platform device */
> +       struct resource res = {
> +               .start = r->start,
> +               .end = r->end,
> +               .flags = IORESOURCE_MEM,
> +       };
> +       struct platform_device *pdev;
> +       struct memregion_info info;
> +       int rc, id;
> +
> +       rc = region_intersects(res.start, resource_size(&res), IORESOURCE_MEM,
> +                       IORES_DESC_APPLICATION_RESERVED);
> +       if (rc != REGION_INTERSECTS)
> +               return;
> +
> +       id = memregion_alloc(GFP_KERNEL);
> +       if (id < 0) {
> +               pr_err("memregion allocation failure for %pr\n", &res);
> +               return;
> +       }
> +
> +       pdev = platform_device_alloc("hmem", id);
> +       if (!pdev) {
> +               pr_err("hmem device allocation failure for %pr\n", &res);
> +               goto out_pdev;
> +       }
> +
> +       pdev->dev.numa_node = acpi_map_pxm_to_online_node(target->memory_pxm);
> +       info = (struct memregion_info) {
> +               .target_node = acpi_map_pxm_to_node(target->memory_pxm),
> +       };
> +       rc = platform_device_add_data(pdev, &info, sizeof(info));
> +       if (rc < 0) {
> +               pr_err("hmem memregion_info allocation failure for %pr\n", &res);
> +               goto out_pdev;
> +       }
> +
> +       rc = platform_device_add_resources(pdev, &res, 1);
> +       if (rc < 0) {
> +               pr_err("hmem resource allocation failure for %pr\n", &res);
> +               goto out_resource;
> +       }
> +
> +       rc = platform_device_add(pdev);
> +       if (rc < 0) {
> +               dev_err(&pdev->dev, "device add failed for %pr\n", &res);
> +               goto out_resource;
> +       }
> +
> +       return;
> +
> +out_resource:
> +       put_device(&pdev->dev);
> +out_pdev:
> +       memregion_free(id);
> +}
> +
> +static __init void hmat_register_target_devices(struct memory_target *target)
> +{
> +       struct resource *res;
> +
> +       /*
> +        * Do not bother creating devices if no driver is available to
> +        * consume them.
> +        */
> +       if (!IS_ENABLED(CONFIG_DEV_DAX_HMEM))
> +               return;
> +
> +       for (res = target->memregions.child; res; res = res->sibling)
> +               hmat_register_target_device(target, res);
> +}
> +
>  static __init void hmat_register_targets(void)
>  {
>         struct memory_target *target;
> @@ -587,6 +682,12 @@ static __init void hmat_register_targets(void)
>         list_for_each_entry(target, &targets, node) {
>                 int nid = pxm_to_node(target->memory_pxm);
>
> +               /*
> +                * Devices may belong to either an offline or online
> +                * node, so unconditionally add them.
> +                */
> +               hmat_register_target_devices(target);
> +
>                 /*
>                  * Skip offline nodes. This can happen when memory
>                  * marked EFI_MEMORY_SP, "specific purpose", is applied
> @@ -608,7 +709,16 @@ static __init void hmat_free_structures(void)
>         struct memory_initiator *initiator, *inext;
>
>         list_for_each_entry_safe(target, tnext, &targets, node) {
> +               struct resource *res, *res_next;
> +
>                 list_del(&target->node);
> +               res = target->memregions.child;
> +               while (res) {
> +                       res_next = res->sibling;
> +                       __release_region(&target->memregions, res->start,
> +                                       resource_size(res));
> +                       res = res_next;
> +               }
>                 kfree(target);
>         }
>
>

^ permalink raw reply	[flat|nested] 21+ messages in thread

end of thread, other threads:[~2019-07-03 11:17 UTC | newest]

Thread overview: 21+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-06-24 18:19 [PATCH v4 00/10] EFI Specific Purpose Memory Support Dan Williams
2019-06-24 18:19 ` [PATCH v4 01/10] acpi/numa: Establish a new drivers/acpi/numa/ directory Dan Williams
2019-06-25 14:59   ` Jonathan Cameron
2019-06-25 16:02     ` Dan Williams
2019-07-03 11:09   ` Rafael J. Wysocki
2019-06-24 18:19 ` [PATCH v4 02/10] acpi/numa/hmat: Skip publishing target info for nodes with no online memory Dan Williams
2019-07-03 11:10   ` Rafael J. Wysocki
2019-06-24 18:19 ` [PATCH v4 03/10] efi: Enumerate EFI_MEMORY_SP Dan Williams
2019-06-24 18:19 ` [PATCH v4 04/10] x86, efi: Push EFI_MEMMAP check into leaf routines Dan Williams
2019-06-24 18:19 ` [PATCH v4 05/10] x86, efi: Reserve UEFI 2.8 Specific Purpose Memory for dax Dan Williams
2019-06-25 15:26   ` Jonathan Cameron
2019-06-24 18:20 ` [PATCH v4 06/10] x86, efi: Add efi_fake_mem support for EFI_MEMORY_SP Dan Williams
2019-06-24 18:20 ` [PATCH v4 07/10] resource: Uplevel the pmem "region" ida to a global allocator Dan Williams
2019-06-24 18:20 ` [PATCH v4 08/10] device-dax: Add a driver for "hmem" devices Dan Williams
2019-06-25 15:37   ` Jonathan Cameron
2019-06-25 20:07     ` Dan Williams
2019-06-24 18:20 ` [PATCH v4 09/10] acpi/numa/hmat: Register HMAT at device_initcall level Dan Williams
2019-07-03 11:12   ` Rafael J. Wysocki
2019-06-24 18:20 ` [PATCH v4 10/10] acpi/numa/hmat: Register "specific purpose" memory as an "hmem" device Dan Williams
2019-06-25 15:58   ` Jonathan Cameron
2019-07-03 11:17   ` Rafael J. Wysocki

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