Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751922AbbDSHqp (ORCPT ); Sun, 19 Apr 2015 03:46:45 -0400 Received: from mail-wg0-f53.google.com ([74.125.82.53]:33624 "EHLO mail-wg0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750806AbbDSHqm (ORCPT ); Sun, 19 Apr 2015 03:46:42 -0400 Message-ID: <55335D5E.40806@plexistor.com> Date: Sun, 19 Apr 2015 10:46:38 +0300 From: Boaz Harrosh User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: Dan Williams , linux-nvdimm@ml01.01.org CC: linux-kernel@vger.kernel.org, Andy Lutomirski , Jens Axboe , "H. Peter Anvin" , Ross Zwisler , Christoph Hellwig , Ingo Molnar Subject: Re: [PATCH 01/21] e820, efi: add ACPI 6.0 persistent memory types References: <20150418013256.25237.96403.stgit@dwillia2-desk3.amr.corp.intel.com> <20150418013519.25237.16129.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <20150418013519.25237.16129.stgit@dwillia2-desk3.amr.corp.intel.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7020 Lines: 208 On 04/18/2015 04:35 AM, Dan Williams wrote: > 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). We may choose to exploit this wealth of definitions for > NVDIMMs to differentiate E820_PRAM (type-12) from E820_PMEM (type-7). > One potential differentiation is that PMEM is not backed by struct page > by default in contrast to PRAM. For now, they are effectively treated > as aliases by the mm. > > Note, /proc/iomem can be consulted for differentiating legacy > "Persistent RAM" E820_PRAM vs standard "Persistent I/O Memory" > E820_PMEM. > > Cc: Andy Lutomirski > Cc: Boaz Harrosh > Cc: H. Peter Anvin > Cc: Jens Axboe > Cc: Ingo Molnar > Cc: Christoph Hellwig > Signed-off-by: Dan Williams > Reviewed-by: Ross Zwisler > --- > arch/arm64/kernel/efi.c | 1 + > arch/ia64/kernel/efi.c | 1 + > arch/x86/boot/compressed/eboot.c | 4 ++++ > arch/x86/include/uapi/asm/e820.h | 1 + > arch/x86/kernel/e820.c | 25 +++++++++++++++++++------ > arch/x86/platform/efi/efi.c | 3 +++ > include/linux/efi.h | 3 ++- > 7 files changed, 31 insertions(+), 7 deletions(-) > > diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c > index ab21e0d58278..9d4aa18f2a82 100644 > --- a/arch/arm64/kernel/efi.c > +++ b/arch/arm64/kernel/efi.c > @@ -158,6 +158,7 @@ static __init int is_reserve_region(efi_memory_desc_t *md) > case EFI_BOOT_SERVICES_CODE: > case EFI_BOOT_SERVICES_DATA: > case EFI_CONVENTIONAL_MEMORY: > + case EFI_PERSISTENT_MEMORY: > return 0; > default: > break; > diff --git a/arch/ia64/kernel/efi.c b/arch/ia64/kernel/efi.c > index c52d7540dc05..cd8b7485e396 100644 > --- a/arch/ia64/kernel/efi.c > +++ b/arch/ia64/kernel/efi.c > @@ -1227,6 +1227,7 @@ efi_initialize_iomem_resources(struct resource *code_resource, > case EFI_RUNTIME_SERVICES_CODE: > case EFI_RUNTIME_SERVICES_DATA: > case EFI_ACPI_RECLAIM_MEMORY: > + case EFI_PERSISTENT_MEMORY: > default: > name = "reserved"; > break; > diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c > index ef17683484e9..dde5bf7726f4 100644 > --- a/arch/x86/boot/compressed/eboot.c > +++ b/arch/x86/boot/compressed/eboot.c > @@ -1222,6 +1222,10 @@ static efi_status_t setup_e820(struct boot_params *params, > e820_type = E820_NVS; > break; > > + case EFI_PERSISTENT_MEMORY: > + e820_type = E820_PMEM; > + break; > + > default: > continue; > } > diff --git a/arch/x86/include/uapi/asm/e820.h b/arch/x86/include/uapi/asm/e820.h > index 960a8a9dc4ab..0f457e6eab18 100644 > --- a/arch/x86/include/uapi/asm/e820.h > +++ b/arch/x86/include/uapi/asm/e820.h > @@ -32,6 +32,7 @@ > #define E820_ACPI 3 > #define E820_NVS 4 > #define E820_UNUSABLE 5 > +#define E820_PMEM 7 > > /* > * This is a non-standardized way to represent ADR or NVDIMM regions that > diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c > index 11cc7d54ec3f..410af501a941 100644 > --- a/arch/x86/kernel/e820.c > +++ b/arch/x86/kernel/e820.c > @@ -137,6 +137,8 @@ static void __init e820_print_type(u32 type) > case E820_RESERVED_KERN: > printk(KERN_CONT "usable"); > break; > + case E820_PMEM: > + case E820_PRAM: NACK! This is the most important print in the system and it is a pure user Interface. It has no effect what so ever on functionality It is to Inform the user through dmesg what is the content of the table. > case E820_RESERVED: > printk(KERN_CONT "reserved"); > break; > @@ -149,9 +151,6 @@ 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; Just add the new (7) entry here please. Here Christoph has bike shed it for you. > default: > printk(KERN_CONT "type %u", type); > break; > @@ -919,10 +918,26 @@ static inline const char *e820_type_to_string(int e820_type) > case E820_NVS: return "ACPI Non-volatile Storage"; > case E820_UNUSABLE: return "Unusable memory"; > case E820_PRAM: return "Persistent RAM"; > + case E820_PMEM: return "Persistent I/O Memory"; > default: return "reserved"; > } > } > > +static bool do_mark_busy(u32 type, struct resource *res) > +{ > + if (res->start < (1ULL<<20)) > + return true; > + > + switch (type) { > + case E820_RESERVED: > + case E820_PRAM: > + case E820_PMEM: > + return false; > + default: > + return true; > + } Sigh. Again an unknown type comes out busy. Busy means resource used. It does *not* mean "unknown type". It just forces researchers to ignore the return value of request_region. And not be protected by double lock. It does not really prevent anything Thanks Boaz > +} > + > /* > * Mark e820 reserved areas as busy for the resource manager. > */ > @@ -952,9 +967,7 @@ 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); > } > diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c > index dbc8627a5cdf..a116e236ac3f 100644 > --- a/arch/x86/platform/efi/efi.c > +++ b/arch/x86/platform/efi/efi.c > @@ -145,6 +145,9 @@ static void __init do_add_efi_memmap(void) > case EFI_UNUSABLE_MEMORY: > e820_type = E820_UNUSABLE; > break; > + case EFI_PERSISTENT_MEMORY: > + e820_type = E820_PMEM; > + break; > default: > /* > * EFI_RESERVED_TYPE EFI_RUNTIME_SERVICES_CODE > diff --git a/include/linux/efi.h b/include/linux/efi.h > index cf7e431cbc73..28868504aa17 100644 > --- a/include/linux/efi.h > +++ b/include/linux/efi.h > @@ -85,7 +85,8 @@ typedef struct { > #define EFI_MEMORY_MAPPED_IO 11 > #define EFI_MEMORY_MAPPED_IO_PORT_SPACE 12 > #define EFI_PAL_CODE 13 > -#define EFI_MAX_MEMORY_TYPE 14 > +#define EFI_PERSISTENT_MEMORY 14 > +#define EFI_MAX_MEMORY_TYPE 15 > > /* Attribute values: */ > #define EFI_MEMORY_UC ((u64)0x0000000000000001ULL) /* uncached */ > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/