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e820, efi: add ACPI 6.0 persistent memory types

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ACPI 6.0 formalizes e820-type-7 and efi-type-14 as persistent memory.
Mark it "reserved" and allow it to be claimed by a persistent memory
device driver.

This definition is in addition to the Linux kernel's existing type-12
definition that was recently added in support of shipping platforms with
NVDIMM support that predate ACPI 6.0 (which now classifies type-12 as
OEM reserved).

Note, /proc/iomem can be consulted for differentiating legacy
"Persistent Memory (legacy)" E820_PRAM vs standard "Persistent Memory"
E820_PMEM.

Cc: Boaz Harrosh <boaz@plexistor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Tested-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Dan Williams
2015-04-03 12:05:28 -04:00
parent f3b6ced236
commit ad5fb870c4
7 changed files with 39 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

28
arch/x86/kernel/e820.c
View File

@@ -149,6 +149,7 @@ static void __init e820_print_type(u32 type)
case E820_UNUSABLE:
printk(KERN_CONT "unusable");
break;
case E820_PMEM:
case E820_PRAM:
printk(KERN_CONT "persistent (type %u)", type);
break;
@@ -918,11 +919,32 @@ static inline const char *e820_type_to_string(int e820_type)
case E820_ACPI: return "ACPI Tables";
case E820_NVS: return "ACPI Non-volatile Storage";
case E820_UNUSABLE: return "Unusable memory";
case E820_PRAM: return "Persistent RAM";
case E820_PRAM: return "Persistent Memory (legacy)";
case E820_PMEM: return "Persistent Memory";
default: return "reserved";
}
}
static bool do_mark_busy(u32 type, struct resource *res)
{
/* this is the legacy bios/dos rom-shadow + mmio region */
if (res->start < (1ULL<<20))
return true;
/*
* Treat persistent memory like device memory, i.e. reserve it
* for exclusive use of a driver
*/
switch (type) {
case E820_RESERVED:
case E820_PRAM:
case E820_PMEM:
return false;
default:
return true;
}
}
/*
* Mark e820 reserved areas as busy for the resource manager.
*/
@@ -952,9 +974,7 @@ void __init e820_reserve_resources(void)
* pci device BAR resource and insert them later in
* pcibios_resource_survey()
*/
if (((e820.map[i].type != E820_RESERVED) &&
(e820.map[i].type != E820_PRAM)) ||
res->start < (1ULL<<20)) {
if (do_mark_busy(e820.map[i].type, res)) {
res->flags |= IORESOURCE_BUSY;
insert_resource(&iomem_resource, res);
}