subject:"\[PATCH v2\] libnvdimm, nfit\: treat volatile virtual CD region as pmem"

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

2016-06-27 Thread Linda Knippers



On 6/27/2016 3:11 AM, joeyli wrote:
> On Sat, Jun 25, 2016 at 09:08:16AM -0700, Dan Williams wrote:
>> On Sat, Jun 25, 2016 at 5:21 AM, joeyli  wrote:
>>> iOn Fri, Jun 24, 2016 at 10:59:56AM -0700, Dan Williams wrote:
 On Fri, Jun 24, 2016 at 12:51 AM, Lee, Chun-Yi  
 wrote:
> This patch adds logic to treat volatile virtual CD region as pmem
> region, then /dev/pmem* device can be mounted with iso9660.
>
> It's useful to work with the httpboot in EFI firmware to pull a remote
> ISO file to the local memory region for booting and installation.
>
> Wiki page of UEFI HTTPBoot with OVMF:
> https://en.opensuse.org/UEFI_HTTPBoot_with_OVMF
>
> The ramdisk function in EDK2/OVMF generates a ACPI0012 root device that
> it contains empty _STA but without _DSM:
>
> DefinitionBlock ("ssdt2.aml", "SSDT", 2, "INTEL ", "RamDisk ", 0x1000)
> {
> Scope (\_SB)
> {
> Device (NVDR)
> {
> Name (_HID, "ACPI0012")  // _HID: Hardware ID
> Name (_STR, Unicode ("NVDIMM Root Device"))  // _STR: 
> Description String
> Method (_STA, 0, NotSerialized)  // _STA: Status
> {
> Return (0x0F)
> }
> }
> }
> }
>
> In section 5.2.25.2 of ACPI 6.1 spec, it mentions that the "SPA Range
> Structure Index" of VCD SPA shall be set to zero. That means VCD SPA
> will not be associated by any NVDIMM region mapping.
>
> The VCD's SPA Range Structure in NFIT is similar to virtual disk region
> as following:
>
> [028h 0040   2]Subtable Type :  [System Physical 
> Address Range]
> [02Ah 0042   2]   Length : 0038
>
> [02Ch 0044   2]  Range Index : 
> [02Eh 0046   2]Flags (decoded below) : 
>Add/Online Operation Only : 0
>   Proximity Domain Valid : 0
> [030h 0048   4] Reserved : 
> [034h 0052   4] Proximity Domain : 
> [038h 0056  16]   Address Range GUID : 
> 77AB535A-45FC-624B-5560-F7B281D1F96E
> [048h 0072   8]   Address Range Base : B6ABD018
> [050h 0080   8] Address Range Length : 0550
> [058h 0088   8] Memory Map Attribute : 
>
> The range index set to zero that means the VCD region not associated by
> any NVDIMM region mapping, and it will not assoicate to "flush hint",
> "interleave" or "control region".

 No, per the spec zero is a reserved value and we should ignore such
 SPA tables.  The way to not associate a SPA range is to never
 reference it from a "flush hint", "interleave", or "control region"
 table.

>>>
>>> In 5.2.25.2 section of ACPI 6.1 spec, it mentions:
>>>
>>> Platform is allowed to implement this structure just to describe system
>>> physical address ranges that describe Virtual CD and Virtual Disk. For
>>> Virtual CD Region and Virtual Disk Region (both volatile and persistent),
>>> the following fields - Proximity Domain, SPA Range Structure Index, Flags, 
>>> and
>>> ^^^
>>> Address Range Memory Mapping Attribute, are not relevant and shall be set 
>>> to 0.
>>> 
>>> ^^^
>>>
>>> The above sentences conflict with the "SPA Range Structure Index" 
>>> description
>>> in Table 5-128 because the SPA index _shall_ be set to zero for virtual CD 
>>> and
>>> virtual Disk. Looks the "SPA index" is not really _reserved_.
>>
>> If we had multiple VCD regions userspace would benefit from some way
>> to the distinguish them which is why sysfs exports the spa range
>> index.  If there are no memdev associations the spa range index is
>> likely the only identifying attribute we have left.
>>
> 
> Yes, this is a benefit when using multiple VCD regions. 
> 
> Maybe the SPA index of VCD doesn't need to be zero, and it also doesn't need
> associated by NVDIMM region mapping. But ACPI spec needs to be changed.
> 
> Hi Linda, do you have any opinion for that the VCD SPA index shell be set to 
> zero? 

My opinion is that we should fix the spec.  But in the meantime, I think the
value should be zero.

My  understanding is that the primary use of this feature is to support
http boot with UEFI and in that case, there is probably only one device.
I think having these as "pmem" devices is already confusing so what's a little
more confusion if we end up with more than one of them.

-- ljk

>  
>>>
>
> After testing on OVMF, pmem driver can support the region that it doesn't
> assoicate to any NVDIMM mapping. So, treat VCD as pmem is a idea to get
> a pmem block

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

2016-06-27 Thread Linda Knippers



On 6/27/2016 3:11 AM, joeyli wrote:
> On Sat, Jun 25, 2016 at 09:08:16AM -0700, Dan Williams wrote:
>> On Sat, Jun 25, 2016 at 5:21 AM, joeyli  wrote:
>>> iOn Fri, Jun 24, 2016 at 10:59:56AM -0700, Dan Williams wrote:
 On Fri, Jun 24, 2016 at 12:51 AM, Lee, Chun-Yi  
 wrote:
> This patch adds logic to treat volatile virtual CD region as pmem
> region, then /dev/pmem* device can be mounted with iso9660.
>
> It's useful to work with the httpboot in EFI firmware to pull a remote
> ISO file to the local memory region for booting and installation.
>
> Wiki page of UEFI HTTPBoot with OVMF:
> https://en.opensuse.org/UEFI_HTTPBoot_with_OVMF
>
> The ramdisk function in EDK2/OVMF generates a ACPI0012 root device that
> it contains empty _STA but without _DSM:
>
> DefinitionBlock ("ssdt2.aml", "SSDT", 2, "INTEL ", "RamDisk ", 0x1000)
> {
> Scope (\_SB)
> {
> Device (NVDR)
> {
> Name (_HID, "ACPI0012")  // _HID: Hardware ID
> Name (_STR, Unicode ("NVDIMM Root Device"))  // _STR: 
> Description String
> Method (_STA, 0, NotSerialized)  // _STA: Status
> {
> Return (0x0F)
> }
> }
> }
> }
>
> In section 5.2.25.2 of ACPI 6.1 spec, it mentions that the "SPA Range
> Structure Index" of VCD SPA shall be set to zero. That means VCD SPA
> will not be associated by any NVDIMM region mapping.
>
> The VCD's SPA Range Structure in NFIT is similar to virtual disk region
> as following:
>
> [028h 0040   2]Subtable Type :  [System Physical 
> Address Range]
> [02Ah 0042   2]   Length : 0038
>
> [02Ch 0044   2]  Range Index : 
> [02Eh 0046   2]Flags (decoded below) : 
>Add/Online Operation Only : 0
>   Proximity Domain Valid : 0
> [030h 0048   4] Reserved : 
> [034h 0052   4] Proximity Domain : 
> [038h 0056  16]   Address Range GUID : 
> 77AB535A-45FC-624B-5560-F7B281D1F96E
> [048h 0072   8]   Address Range Base : B6ABD018
> [050h 0080   8] Address Range Length : 0550
> [058h 0088   8] Memory Map Attribute : 
>
> The range index set to zero that means the VCD region not associated by
> any NVDIMM region mapping, and it will not assoicate to "flush hint",
> "interleave" or "control region".

 No, per the spec zero is a reserved value and we should ignore such
 SPA tables.  The way to not associate a SPA range is to never
 reference it from a "flush hint", "interleave", or "control region"
 table.

>>>
>>> In 5.2.25.2 section of ACPI 6.1 spec, it mentions:
>>>
>>> Platform is allowed to implement this structure just to describe system
>>> physical address ranges that describe Virtual CD and Virtual Disk. For
>>> Virtual CD Region and Virtual Disk Region (both volatile and persistent),
>>> the following fields - Proximity Domain, SPA Range Structure Index, Flags, 
>>> and
>>> ^^^
>>> Address Range Memory Mapping Attribute, are not relevant and shall be set 
>>> to 0.
>>> 
>>> ^^^
>>>
>>> The above sentences conflict with the "SPA Range Structure Index" 
>>> description
>>> in Table 5-128 because the SPA index _shall_ be set to zero for virtual CD 
>>> and
>>> virtual Disk. Looks the "SPA index" is not really _reserved_.
>>
>> If we had multiple VCD regions userspace would benefit from some way
>> to the distinguish them which is why sysfs exports the spa range
>> index.  If there are no memdev associations the spa range index is
>> likely the only identifying attribute we have left.
>>
> 
> Yes, this is a benefit when using multiple VCD regions. 
> 
> Maybe the SPA index of VCD doesn't need to be zero, and it also doesn't need
> associated by NVDIMM region mapping. But ACPI spec needs to be changed.
> 
> Hi Linda, do you have any opinion for that the VCD SPA index shell be set to 
> zero? 

My opinion is that we should fix the spec.  But in the meantime, I think the
value should be zero.

My  understanding is that the primary use of this feature is to support
http boot with UEFI and in that case, there is probably only one device.
I think having these as "pmem" devices is already confusing so what's a little
more confusion if we end up with more than one of them.

-- ljk

>  
>>>
>
> After testing on OVMF, pmem driver can support the region that it doesn't
> assoicate to any NVDIMM mapping. So, treat VCD as pmem is a idea to get
> a pmem block device that it containts iso.
>
> v2

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

2016-06-27 Thread joeyli

On Sat, Jun 25, 2016 at 09:08:16AM -0700, Dan Williams wrote:
> On Sat, Jun 25, 2016 at 5:21 AM, joeyli  wrote:
> > iOn Fri, Jun 24, 2016 at 10:59:56AM -0700, Dan Williams wrote:
> >> On Fri, Jun 24, 2016 at 12:51 AM, Lee, Chun-Yi  
> >> wrote:
> >> > This patch adds logic to treat volatile virtual CD region as pmem
> >> > region, then /dev/pmem* device can be mounted with iso9660.
> >> >
> >> > It's useful to work with the httpboot in EFI firmware to pull a remote
> >> > ISO file to the local memory region for booting and installation.
> >> >
> >> > Wiki page of UEFI HTTPBoot with OVMF:
> >> > https://en.opensuse.org/UEFI_HTTPBoot_with_OVMF
> >> >
> >> > The ramdisk function in EDK2/OVMF generates a ACPI0012 root device that
> >> > it contains empty _STA but without _DSM:
> >> >
> >> > DefinitionBlock ("ssdt2.aml", "SSDT", 2, "INTEL ", "RamDisk ", 
> >> > 0x1000)
> >> > {
> >> > Scope (\_SB)
> >> > {
> >> > Device (NVDR)
> >> > {
> >> > Name (_HID, "ACPI0012")  // _HID: Hardware ID
> >> > Name (_STR, Unicode ("NVDIMM Root Device"))  // _STR: 
> >> > Description String
> >> > Method (_STA, 0, NotSerialized)  // _STA: Status
> >> > {
> >> > Return (0x0F)
> >> > }
> >> > }
> >> > }
> >> > }
> >> >
> >> > In section 5.2.25.2 of ACPI 6.1 spec, it mentions that the "SPA Range
> >> > Structure Index" of VCD SPA shall be set to zero. That means VCD SPA
> >> > will not be associated by any NVDIMM region mapping.
> >> >
> >> > The VCD's SPA Range Structure in NFIT is similar to virtual disk region
> >> > as following:
> >> >
> >> > [028h 0040   2]Subtable Type :  [System Physical 
> >> > Address Range]
> >> > [02Ah 0042   2]   Length : 0038
> >> >
> >> > [02Ch 0044   2]  Range Index : 
> >> > [02Eh 0046   2]Flags (decoded below) : 
> >> >Add/Online Operation Only : 0
> >> >   Proximity Domain Valid : 0
> >> > [030h 0048   4] Reserved : 
> >> > [034h 0052   4] Proximity Domain : 
> >> > [038h 0056  16]   Address Range GUID : 
> >> > 77AB535A-45FC-624B-5560-F7B281D1F96E
> >> > [048h 0072   8]   Address Range Base : B6ABD018
> >> > [050h 0080   8] Address Range Length : 0550
> >> > [058h 0088   8] Memory Map Attribute : 
> >> >
> >> > The range index set to zero that means the VCD region not associated by
> >> > any NVDIMM region mapping, and it will not assoicate to "flush hint",
> >> > "interleave" or "control region".
> >>
> >> No, per the spec zero is a reserved value and we should ignore such
> >> SPA tables.  The way to not associate a SPA range is to never
> >> reference it from a "flush hint", "interleave", or "control region"
> >> table.
> >>
> >
> > In 5.2.25.2 section of ACPI 6.1 spec, it mentions:
> >
> > Platform is allowed to implement this structure just to describe system
> > physical address ranges that describe Virtual CD and Virtual Disk. For
> > Virtual CD Region and Virtual Disk Region (both volatile and persistent),
> > the following fields - Proximity Domain, SPA Range Structure Index, Flags, 
> > and
> > ^^^
> > Address Range Memory Mapping Attribute, are not relevant and shall be set 
> > to 0.
> > 
> > ^^^
> >
> > The above sentences conflict with the "SPA Range Structure Index" 
> > description
> > in Table 5-128 because the SPA index _shall_ be set to zero for virtual CD 
> > and
> > virtual Disk. Looks the "SPA index" is not really _reserved_.
> 
> If we had multiple VCD regions userspace would benefit from some way
> to the distinguish them which is why sysfs exports the spa range
> index.  If there are no memdev associations the spa range index is
> likely the only identifying attribute we have left.
>

Yes, this is a benefit when using multiple VCD regions. 

Maybe the SPA index of VCD doesn't need to be zero, and it also doesn't need
associated by NVDIMM region mapping. But ACPI spec needs to be changed.

Hi Linda, do you have any opinion for that the VCD SPA index shell be set to 
zero? 
 
> >
> >> >
> >> > After testing on OVMF, pmem driver can support the region that it doesn't
> >> > assoicate to any NVDIMM mapping. So, treat VCD as pmem is a idea to get
> >> > a pmem block device that it containts iso.
> >> >
> >> > v2
> >> > Removed the code for setting VCD to a read-only region.
> >> >
> >> > Cc: Gary Lin 
> >> > Cc: Dan Williams 
> >> > Cc: Ross Zwisler 
> >> > Cc: "Rafael J. Wysocki" 
> >> > Cc: Linda Knippers 
> >> > Signed-off-by: Lee,

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

2016-06-27 Thread joeyli

On Sat, Jun 25, 2016 at 09:08:16AM -0700, Dan Williams wrote:
> On Sat, Jun 25, 2016 at 5:21 AM, joeyli  wrote:
> > iOn Fri, Jun 24, 2016 at 10:59:56AM -0700, Dan Williams wrote:
> >> On Fri, Jun 24, 2016 at 12:51 AM, Lee, Chun-Yi  
> >> wrote:
> >> > This patch adds logic to treat volatile virtual CD region as pmem
> >> > region, then /dev/pmem* device can be mounted with iso9660.
> >> >
> >> > It's useful to work with the httpboot in EFI firmware to pull a remote
> >> > ISO file to the local memory region for booting and installation.
> >> >
> >> > Wiki page of UEFI HTTPBoot with OVMF:
> >> > https://en.opensuse.org/UEFI_HTTPBoot_with_OVMF
> >> >
> >> > The ramdisk function in EDK2/OVMF generates a ACPI0012 root device that
> >> > it contains empty _STA but without _DSM:
> >> >
> >> > DefinitionBlock ("ssdt2.aml", "SSDT", 2, "INTEL ", "RamDisk ", 
> >> > 0x1000)
> >> > {
> >> > Scope (\_SB)
> >> > {
> >> > Device (NVDR)
> >> > {
> >> > Name (_HID, "ACPI0012")  // _HID: Hardware ID
> >> > Name (_STR, Unicode ("NVDIMM Root Device"))  // _STR: 
> >> > Description String
> >> > Method (_STA, 0, NotSerialized)  // _STA: Status
> >> > {
> >> > Return (0x0F)
> >> > }
> >> > }
> >> > }
> >> > }
> >> >
> >> > In section 5.2.25.2 of ACPI 6.1 spec, it mentions that the "SPA Range
> >> > Structure Index" of VCD SPA shall be set to zero. That means VCD SPA
> >> > will not be associated by any NVDIMM region mapping.
> >> >
> >> > The VCD's SPA Range Structure in NFIT is similar to virtual disk region
> >> > as following:
> >> >
> >> > [028h 0040   2]Subtable Type :  [System Physical 
> >> > Address Range]
> >> > [02Ah 0042   2]   Length : 0038
> >> >
> >> > [02Ch 0044   2]  Range Index : 
> >> > [02Eh 0046   2]Flags (decoded below) : 
> >> >Add/Online Operation Only : 0
> >> >   Proximity Domain Valid : 0
> >> > [030h 0048   4] Reserved : 
> >> > [034h 0052   4] Proximity Domain : 
> >> > [038h 0056  16]   Address Range GUID : 
> >> > 77AB535A-45FC-624B-5560-F7B281D1F96E
> >> > [048h 0072   8]   Address Range Base : B6ABD018
> >> > [050h 0080   8] Address Range Length : 0550
> >> > [058h 0088   8] Memory Map Attribute : 
> >> >
> >> > The range index set to zero that means the VCD region not associated by
> >> > any NVDIMM region mapping, and it will not assoicate to "flush hint",
> >> > "interleave" or "control region".
> >>
> >> No, per the spec zero is a reserved value and we should ignore such
> >> SPA tables.  The way to not associate a SPA range is to never
> >> reference it from a "flush hint", "interleave", or "control region"
> >> table.
> >>
> >
> > In 5.2.25.2 section of ACPI 6.1 spec, it mentions:
> >
> > Platform is allowed to implement this structure just to describe system
> > physical address ranges that describe Virtual CD and Virtual Disk. For
> > Virtual CD Region and Virtual Disk Region (both volatile and persistent),
> > the following fields - Proximity Domain, SPA Range Structure Index, Flags, 
> > and
> > ^^^
> > Address Range Memory Mapping Attribute, are not relevant and shall be set 
> > to 0.
> > 
> > ^^^
> >
> > The above sentences conflict with the "SPA Range Structure Index" 
> > description
> > in Table 5-128 because the SPA index _shall_ be set to zero for virtual CD 
> > and
> > virtual Disk. Looks the "SPA index" is not really _reserved_.
> 
> If we had multiple VCD regions userspace would benefit from some way
> to the distinguish them which is why sysfs exports the spa range
> index.  If there are no memdev associations the spa range index is
> likely the only identifying attribute we have left.
>

Yes, this is a benefit when using multiple VCD regions. 

Maybe the SPA index of VCD doesn't need to be zero, and it also doesn't need
associated by NVDIMM region mapping. But ACPI spec needs to be changed.

Hi Linda, do you have any opinion for that the VCD SPA index shell be set to 
zero? 
 
> >
> >> >
> >> > After testing on OVMF, pmem driver can support the region that it doesn't
> >> > assoicate to any NVDIMM mapping. So, treat VCD as pmem is a idea to get
> >> > a pmem block device that it containts iso.
> >> >
> >> > v2
> >> > Removed the code for setting VCD to a read-only region.
> >> >
> >> > Cc: Gary Lin 
> >> > Cc: Dan Williams 
> >> > Cc: Ross Zwisler 
> >> > Cc: "Rafael J. Wysocki" 
> >> > Cc: Linda Knippers 
> >> > Signed-off-by: Lee, Chun-Yi 
> >> > ---
> >> >  drivers/acpi/nfit.c  |  8 +++-
> >> >  drivers/nvdimm/region_devs.c | 26 +-
> >> >

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

2016-06-25 Thread Dan Williams

On Sat, Jun 25, 2016 at 5:21 AM, joeyli  wrote:
> iOn Fri, Jun 24, 2016 at 10:59:56AM -0700, Dan Williams wrote:
>> On Fri, Jun 24, 2016 at 12:51 AM, Lee, Chun-Yi  
>> wrote:
>> > This patch adds logic to treat volatile virtual CD region as pmem
>> > region, then /dev/pmem* device can be mounted with iso9660.
>> >
>> > It's useful to work with the httpboot in EFI firmware to pull a remote
>> > ISO file to the local memory region for booting and installation.
>> >
>> > Wiki page of UEFI HTTPBoot with OVMF:
>> > https://en.opensuse.org/UEFI_HTTPBoot_with_OVMF
>> >
>> > The ramdisk function in EDK2/OVMF generates a ACPI0012 root device that
>> > it contains empty _STA but without _DSM:
>> >
>> > DefinitionBlock ("ssdt2.aml", "SSDT", 2, "INTEL ", "RamDisk ", 0x1000)
>> > {
>> > Scope (\_SB)
>> > {
>> > Device (NVDR)
>> > {
>> > Name (_HID, "ACPI0012")  // _HID: Hardware ID
>> > Name (_STR, Unicode ("NVDIMM Root Device"))  // _STR: 
>> > Description String
>> > Method (_STA, 0, NotSerialized)  // _STA: Status
>> > {
>> > Return (0x0F)
>> > }
>> > }
>> > }
>> > }
>> >
>> > In section 5.2.25.2 of ACPI 6.1 spec, it mentions that the "SPA Range
>> > Structure Index" of VCD SPA shall be set to zero. That means VCD SPA
>> > will not be associated by any NVDIMM region mapping.
>> >
>> > The VCD's SPA Range Structure in NFIT is similar to virtual disk region
>> > as following:
>> >
>> > [028h 0040   2]Subtable Type :  [System Physical 
>> > Address Range]
>> > [02Ah 0042   2]   Length : 0038
>> >
>> > [02Ch 0044   2]  Range Index : 
>> > [02Eh 0046   2]Flags (decoded below) : 
>> >Add/Online Operation Only : 0
>> >   Proximity Domain Valid : 0
>> > [030h 0048   4] Reserved : 
>> > [034h 0052   4] Proximity Domain : 
>> > [038h 0056  16]   Address Range GUID : 
>> > 77AB535A-45FC-624B-5560-F7B281D1F96E
>> > [048h 0072   8]   Address Range Base : B6ABD018
>> > [050h 0080   8] Address Range Length : 0550
>> > [058h 0088   8] Memory Map Attribute : 
>> >
>> > The range index set to zero that means the VCD region not associated by
>> > any NVDIMM region mapping, and it will not assoicate to "flush hint",
>> > "interleave" or "control region".
>>
>> No, per the spec zero is a reserved value and we should ignore such
>> SPA tables.  The way to not associate a SPA range is to never
>> reference it from a "flush hint", "interleave", or "control region"
>> table.
>>
>
> In 5.2.25.2 section of ACPI 6.1 spec, it mentions:
>
> Platform is allowed to implement this structure just to describe system
> physical address ranges that describe Virtual CD and Virtual Disk. For
> Virtual CD Region and Virtual Disk Region (both volatile and persistent),
> the following fields - Proximity Domain, SPA Range Structure Index, Flags, and
> ^^^
> Address Range Memory Mapping Attribute, are not relevant and shall be set to 
> 0.
> 
> ^^^
>
> The above sentences conflict with the "SPA Range Structure Index" description
> in Table 5-128 because the SPA index _shall_ be set to zero for virtual CD and
> virtual Disk. Looks the "SPA index" is not really _reserved_.

If we had multiple VCD regions userspace would benefit from some way
to the distinguish them which is why sysfs exports the spa range
index.  If there are no memdev associations the spa range index is
likely the only identifying attribute we have left.

>
>> >
>> > After testing on OVMF, pmem driver can support the region that it doesn't
>> > assoicate to any NVDIMM mapping. So, treat VCD as pmem is a idea to get
>> > a pmem block device that it containts iso.
>> >
>> > v2
>> > Removed the code for setting VCD to a read-only region.
>> >
>> > Cc: Gary Lin 
>> > Cc: Dan Williams 
>> > Cc: Ross Zwisler 
>> > Cc: "Rafael J. Wysocki" 
>> > Cc: Linda Knippers 
>> > Signed-off-by: Lee, Chun-Yi 
>> > ---
>> >  drivers/acpi/nfit.c  |  8 +++-
>> >  drivers/nvdimm/region_devs.c | 26 +-
>> >  include/linux/libnvdimm.h|  2 ++
>> >  3 files changed, 34 insertions(+), 2 deletions(-)
>> >
>>
>> I don't think we need "nd_vcd_device_type".  I think this patch can
>> just be reduced to:
>>
>> diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
>> index 32579a7b71d5..d289e772c20a 100644
>> --- a/drivers/acpi/nfit.c
>> +++ b/drivers/acpi/nfit.c
>> @@ -1948,6 +1948,7 @@ static int acpi_nfit_init_mapping(struct
>>

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

2016-06-25 Thread Dan Williams

On Sat, Jun 25, 2016 at 5:21 AM, joeyli  wrote:
> iOn Fri, Jun 24, 2016 at 10:59:56AM -0700, Dan Williams wrote:
>> On Fri, Jun 24, 2016 at 12:51 AM, Lee, Chun-Yi  
>> wrote:
>> > This patch adds logic to treat volatile virtual CD region as pmem
>> > region, then /dev/pmem* device can be mounted with iso9660.
>> >
>> > It's useful to work with the httpboot in EFI firmware to pull a remote
>> > ISO file to the local memory region for booting and installation.
>> >
>> > Wiki page of UEFI HTTPBoot with OVMF:
>> > https://en.opensuse.org/UEFI_HTTPBoot_with_OVMF
>> >
>> > The ramdisk function in EDK2/OVMF generates a ACPI0012 root device that
>> > it contains empty _STA but without _DSM:
>> >
>> > DefinitionBlock ("ssdt2.aml", "SSDT", 2, "INTEL ", "RamDisk ", 0x1000)
>> > {
>> > Scope (\_SB)
>> > {
>> > Device (NVDR)
>> > {
>> > Name (_HID, "ACPI0012")  // _HID: Hardware ID
>> > Name (_STR, Unicode ("NVDIMM Root Device"))  // _STR: 
>> > Description String
>> > Method (_STA, 0, NotSerialized)  // _STA: Status
>> > {
>> > Return (0x0F)
>> > }
>> > }
>> > }
>> > }
>> >
>> > In section 5.2.25.2 of ACPI 6.1 spec, it mentions that the "SPA Range
>> > Structure Index" of VCD SPA shall be set to zero. That means VCD SPA
>> > will not be associated by any NVDIMM region mapping.
>> >
>> > The VCD's SPA Range Structure in NFIT is similar to virtual disk region
>> > as following:
>> >
>> > [028h 0040   2]Subtable Type :  [System Physical 
>> > Address Range]
>> > [02Ah 0042   2]   Length : 0038
>> >
>> > [02Ch 0044   2]  Range Index : 
>> > [02Eh 0046   2]Flags (decoded below) : 
>> >Add/Online Operation Only : 0
>> >   Proximity Domain Valid : 0
>> > [030h 0048   4] Reserved : 
>> > [034h 0052   4] Proximity Domain : 
>> > [038h 0056  16]   Address Range GUID : 
>> > 77AB535A-45FC-624B-5560-F7B281D1F96E
>> > [048h 0072   8]   Address Range Base : B6ABD018
>> > [050h 0080   8] Address Range Length : 0550
>> > [058h 0088   8] Memory Map Attribute : 
>> >
>> > The range index set to zero that means the VCD region not associated by
>> > any NVDIMM region mapping, and it will not assoicate to "flush hint",
>> > "interleave" or "control region".
>>
>> No, per the spec zero is a reserved value and we should ignore such
>> SPA tables.  The way to not associate a SPA range is to never
>> reference it from a "flush hint", "interleave", or "control region"
>> table.
>>
>
> In 5.2.25.2 section of ACPI 6.1 spec, it mentions:
>
> Platform is allowed to implement this structure just to describe system
> physical address ranges that describe Virtual CD and Virtual Disk. For
> Virtual CD Region and Virtual Disk Region (both volatile and persistent),
> the following fields - Proximity Domain, SPA Range Structure Index, Flags, and
> ^^^
> Address Range Memory Mapping Attribute, are not relevant and shall be set to 
> 0.
> 
> ^^^
>
> The above sentences conflict with the "SPA Range Structure Index" description
> in Table 5-128 because the SPA index _shall_ be set to zero for virtual CD and
> virtual Disk. Looks the "SPA index" is not really _reserved_.

If we had multiple VCD regions userspace would benefit from some way
to the distinguish them which is why sysfs exports the spa range
index.  If there are no memdev associations the spa range index is
likely the only identifying attribute we have left.

>
>> >
>> > After testing on OVMF, pmem driver can support the region that it doesn't
>> > assoicate to any NVDIMM mapping. So, treat VCD as pmem is a idea to get
>> > a pmem block device that it containts iso.
>> >
>> > v2
>> > Removed the code for setting VCD to a read-only region.
>> >
>> > Cc: Gary Lin 
>> > Cc: Dan Williams 
>> > Cc: Ross Zwisler 
>> > Cc: "Rafael J. Wysocki" 
>> > Cc: Linda Knippers 
>> > Signed-off-by: Lee, Chun-Yi 
>> > ---
>> >  drivers/acpi/nfit.c  |  8 +++-
>> >  drivers/nvdimm/region_devs.c | 26 +-
>> >  include/linux/libnvdimm.h|  2 ++
>> >  3 files changed, 34 insertions(+), 2 deletions(-)
>> >
>>
>> I don't think we need "nd_vcd_device_type".  I think this patch can
>> just be reduced to:
>>
>> diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
>> index 32579a7b71d5..d289e772c20a 100644
>> --- a/drivers/acpi/nfit.c
>> +++ b/drivers/acpi/nfit.c
>> @@ -1948,6 +1948,7 @@ static int acpi_nfit_init_mapping(struct
>> acpi_nfit_desc *acpi_desc,
>> nd_mapping->nvdimm = nvdimm;
>> switch (nfit_spa_type(spa)) {
>> case NFIT_SPA_PM:
>> +   case NFIT_SPA_VCD:
>>

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

2016-06-25 Thread joeyli

iOn Fri, Jun 24, 2016 at 10:59:56AM -0700, Dan Williams wrote:
> On Fri, Jun 24, 2016 at 12:51 AM, Lee, Chun-Yi  
> wrote:
> > This patch adds logic to treat volatile virtual CD region as pmem
> > region, then /dev/pmem* device can be mounted with iso9660.
> >
> > It's useful to work with the httpboot in EFI firmware to pull a remote
> > ISO file to the local memory region for booting and installation.
> >
> > Wiki page of UEFI HTTPBoot with OVMF:
> > https://en.opensuse.org/UEFI_HTTPBoot_with_OVMF
> >
> > The ramdisk function in EDK2/OVMF generates a ACPI0012 root device that
> > it contains empty _STA but without _DSM:
> >
> > DefinitionBlock ("ssdt2.aml", "SSDT", 2, "INTEL ", "RamDisk ", 0x1000)
> > {
> > Scope (\_SB)
> > {
> > Device (NVDR)
> > {
> > Name (_HID, "ACPI0012")  // _HID: Hardware ID
> > Name (_STR, Unicode ("NVDIMM Root Device"))  // _STR: 
> > Description String
> > Method (_STA, 0, NotSerialized)  // _STA: Status
> > {
> > Return (0x0F)
> > }
> > }
> > }
> > }
> >
> > In section 5.2.25.2 of ACPI 6.1 spec, it mentions that the "SPA Range
> > Structure Index" of VCD SPA shall be set to zero. That means VCD SPA
> > will not be associated by any NVDIMM region mapping.
> >
> > The VCD's SPA Range Structure in NFIT is similar to virtual disk region
> > as following:
> >
> > [028h 0040   2]Subtable Type :  [System Physical 
> > Address Range]
> > [02Ah 0042   2]   Length : 0038
> >
> > [02Ch 0044   2]  Range Index : 
> > [02Eh 0046   2]Flags (decoded below) : 
> >Add/Online Operation Only : 0
> >   Proximity Domain Valid : 0
> > [030h 0048   4] Reserved : 
> > [034h 0052   4] Proximity Domain : 
> > [038h 0056  16]   Address Range GUID : 
> > 77AB535A-45FC-624B-5560-F7B281D1F96E
> > [048h 0072   8]   Address Range Base : B6ABD018
> > [050h 0080   8] Address Range Length : 0550
> > [058h 0088   8] Memory Map Attribute : 
> >
> > The range index set to zero that means the VCD region not associated by
> > any NVDIMM region mapping, and it will not assoicate to "flush hint",
> > "interleave" or "control region".
> 
> No, per the spec zero is a reserved value and we should ignore such
> SPA tables.  The way to not associate a SPA range is to never
> reference it from a "flush hint", "interleave", or "control region"
> table.
>

In 5.2.25.2 section of ACPI 6.1 spec, it mentions:

Platform is allowed to implement this structure just to describe system
physical address ranges that describe Virtual CD and Virtual Disk. For
Virtual CD Region and Virtual Disk Region (both volatile and persistent),
the following fields - Proximity Domain, SPA Range Structure Index, Flags, and
^^^
Address Range Memory Mapping Attribute, are not relevant and shall be set to 0.
^^^

The above sentences conflict with the "SPA Range Structure Index" description
in Table 5-128 because the SPA index _shall_ be set to zero for virtual CD and
virtual Disk. Looks the "SPA index" is not really _reserved_.

> >
> > After testing on OVMF, pmem driver can support the region that it doesn't
> > assoicate to any NVDIMM mapping. So, treat VCD as pmem is a idea to get
> > a pmem block device that it containts iso.
> >
> > v2
> > Removed the code for setting VCD to a read-only region.
> >
> > Cc: Gary Lin 
> > Cc: Dan Williams 
> > Cc: Ross Zwisler 
> > Cc: "Rafael J. Wysocki" 
> > Cc: Linda Knippers 
> > Signed-off-by: Lee, Chun-Yi 
> > ---
> >  drivers/acpi/nfit.c  |  8 +++-
> >  drivers/nvdimm/region_devs.c | 26 +-
> >  include/linux/libnvdimm.h|  2 ++
> >  3 files changed, 34 insertions(+), 2 deletions(-)
> >
> 
> I don't think we need "nd_vcd_device_type".  I think this patch can
> just be reduced to:
> 
> diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
> index 32579a7b71d5..d289e772c20a 100644
> --- a/drivers/acpi/nfit.c
> +++ b/drivers/acpi/nfit.c
> @@ -1948,6 +1948,7 @@ static int acpi_nfit_init_mapping(struct
> acpi_nfit_desc *acpi_desc,
> nd_mapping->nvdimm = nvdimm;
> switch (nfit_spa_type(spa)) {
> case NFIT_SPA_PM:
> +   case NFIT_SPA_VCD:
> case NFIT_SPA_VOLATILE:
> nd_mapping->start = memdev->address;
> nd_mapping->size = memdev->region_size;

It does not work.

Actually I removed the above code in version two because it useless.

VCD SPA should not be referenced by any "NVDIMM

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

2016-06-25 Thread joeyli

iOn Fri, Jun 24, 2016 at 10:59:56AM -0700, Dan Williams wrote:
> On Fri, Jun 24, 2016 at 12:51 AM, Lee, Chun-Yi  
> wrote:
> > This patch adds logic to treat volatile virtual CD region as pmem
> > region, then /dev/pmem* device can be mounted with iso9660.
> >
> > It's useful to work with the httpboot in EFI firmware to pull a remote
> > ISO file to the local memory region for booting and installation.
> >
> > Wiki page of UEFI HTTPBoot with OVMF:
> > https://en.opensuse.org/UEFI_HTTPBoot_with_OVMF
> >
> > The ramdisk function in EDK2/OVMF generates a ACPI0012 root device that
> > it contains empty _STA but without _DSM:
> >
> > DefinitionBlock ("ssdt2.aml", "SSDT", 2, "INTEL ", "RamDisk ", 0x1000)
> > {
> > Scope (\_SB)
> > {
> > Device (NVDR)
> > {
> > Name (_HID, "ACPI0012")  // _HID: Hardware ID
> > Name (_STR, Unicode ("NVDIMM Root Device"))  // _STR: 
> > Description String
> > Method (_STA, 0, NotSerialized)  // _STA: Status
> > {
> > Return (0x0F)
> > }
> > }
> > }
> > }
> >
> > In section 5.2.25.2 of ACPI 6.1 spec, it mentions that the "SPA Range
> > Structure Index" of VCD SPA shall be set to zero. That means VCD SPA
> > will not be associated by any NVDIMM region mapping.
> >
> > The VCD's SPA Range Structure in NFIT is similar to virtual disk region
> > as following:
> >
> > [028h 0040   2]Subtable Type :  [System Physical 
> > Address Range]
> > [02Ah 0042   2]   Length : 0038
> >
> > [02Ch 0044   2]  Range Index : 
> > [02Eh 0046   2]Flags (decoded below) : 
> >Add/Online Operation Only : 0
> >   Proximity Domain Valid : 0
> > [030h 0048   4] Reserved : 
> > [034h 0052   4] Proximity Domain : 
> > [038h 0056  16]   Address Range GUID : 
> > 77AB535A-45FC-624B-5560-F7B281D1F96E
> > [048h 0072   8]   Address Range Base : B6ABD018
> > [050h 0080   8] Address Range Length : 0550
> > [058h 0088   8] Memory Map Attribute : 
> >
> > The range index set to zero that means the VCD region not associated by
> > any NVDIMM region mapping, and it will not assoicate to "flush hint",
> > "interleave" or "control region".
> 
> No, per the spec zero is a reserved value and we should ignore such
> SPA tables.  The way to not associate a SPA range is to never
> reference it from a "flush hint", "interleave", or "control region"
> table.
>

In 5.2.25.2 section of ACPI 6.1 spec, it mentions:

Platform is allowed to implement this structure just to describe system
physical address ranges that describe Virtual CD and Virtual Disk. For
Virtual CD Region and Virtual Disk Region (both volatile and persistent),
the following fields - Proximity Domain, SPA Range Structure Index, Flags, and
^^^
Address Range Memory Mapping Attribute, are not relevant and shall be set to 0.
^^^

The above sentences conflict with the "SPA Range Structure Index" description
in Table 5-128 because the SPA index _shall_ be set to zero for virtual CD and
virtual Disk. Looks the "SPA index" is not really _reserved_.

> >
> > After testing on OVMF, pmem driver can support the region that it doesn't
> > assoicate to any NVDIMM mapping. So, treat VCD as pmem is a idea to get
> > a pmem block device that it containts iso.
> >
> > v2
> > Removed the code for setting VCD to a read-only region.
> >
> > Cc: Gary Lin 
> > Cc: Dan Williams 
> > Cc: Ross Zwisler 
> > Cc: "Rafael J. Wysocki" 
> > Cc: Linda Knippers 
> > Signed-off-by: Lee, Chun-Yi 
> > ---
> >  drivers/acpi/nfit.c  |  8 +++-
> >  drivers/nvdimm/region_devs.c | 26 +-
> >  include/linux/libnvdimm.h|  2 ++
> >  3 files changed, 34 insertions(+), 2 deletions(-)
> >
> 
> I don't think we need "nd_vcd_device_type".  I think this patch can
> just be reduced to:
> 
> diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
> index 32579a7b71d5..d289e772c20a 100644
> --- a/drivers/acpi/nfit.c
> +++ b/drivers/acpi/nfit.c
> @@ -1948,6 +1948,7 @@ static int acpi_nfit_init_mapping(struct
> acpi_nfit_desc *acpi_desc,
> nd_mapping->nvdimm = nvdimm;
> switch (nfit_spa_type(spa)) {
> case NFIT_SPA_PM:
> +   case NFIT_SPA_VCD:
> case NFIT_SPA_VOLATILE:
> nd_mapping->start = memdev->address;
> nd_mapping->size = memdev->region_size;

It does not work.

Actually I removed the above code in version two because it useless.

VCD SPA should not be referenced by any "NVDIMM Region Mapping Structure",
so it does not have any memdev in memdevs list for mapping. That means
acpi_nfit_init_mapping() never be called in

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

2016-06-24 Thread Dan Williams

On Fri, Jun 24, 2016 at 12:51 AM, Lee, Chun-Yi  wrote:
> This patch adds logic to treat volatile virtual CD region as pmem
> region, then /dev/pmem* device can be mounted with iso9660.
>
> It's useful to work with the httpboot in EFI firmware to pull a remote
> ISO file to the local memory region for booting and installation.
>
> Wiki page of UEFI HTTPBoot with OVMF:
> https://en.opensuse.org/UEFI_HTTPBoot_with_OVMF
>
> The ramdisk function in EDK2/OVMF generates a ACPI0012 root device that
> it contains empty _STA but without _DSM:
>
> DefinitionBlock ("ssdt2.aml", "SSDT", 2, "INTEL ", "RamDisk ", 0x1000)
> {
> Scope (\_SB)
> {
> Device (NVDR)
> {
> Name (_HID, "ACPI0012")  // _HID: Hardware ID
> Name (_STR, Unicode ("NVDIMM Root Device"))  // _STR: Description 
> String
> Method (_STA, 0, NotSerialized)  // _STA: Status
> {
> Return (0x0F)
> }
> }
> }
> }
>
> In section 5.2.25.2 of ACPI 6.1 spec, it mentions that the "SPA Range
> Structure Index" of VCD SPA shall be set to zero. That means VCD SPA
> will not be associated by any NVDIMM region mapping.
>
> The VCD's SPA Range Structure in NFIT is similar to virtual disk region
> as following:
>
> [028h 0040   2]Subtable Type :  [System Physical Address 
> Range]
> [02Ah 0042   2]   Length : 0038
>
> [02Ch 0044   2]  Range Index : 
> [02Eh 0046   2]Flags (decoded below) : 
>Add/Online Operation Only : 0
>   Proximity Domain Valid : 0
> [030h 0048   4] Reserved : 
> [034h 0052   4] Proximity Domain : 
> [038h 0056  16]   Address Range GUID : 
> 77AB535A-45FC-624B-5560-F7B281D1F96E
> [048h 0072   8]   Address Range Base : B6ABD018
> [050h 0080   8] Address Range Length : 0550
> [058h 0088   8] Memory Map Attribute : 
>
> The range index set to zero that means the VCD region not associated by
> any NVDIMM region mapping, and it will not assoicate to "flush hint",
> "interleave" or "control region".

No, per the spec zero is a reserved value and we should ignore such
SPA tables.  The way to not associate a SPA range is to never
reference it from a "flush hint", "interleave", or "control region"
table.

>
> After testing on OVMF, pmem driver can support the region that it doesn't
> assoicate to any NVDIMM mapping. So, treat VCD as pmem is a idea to get
> a pmem block device that it containts iso.
>
> v2
> Removed the code for setting VCD to a read-only region.
>
> Cc: Gary Lin 
> Cc: Dan Williams 
> Cc: Ross Zwisler 
> Cc: "Rafael J. Wysocki" 
> Cc: Linda Knippers 
> Signed-off-by: Lee, Chun-Yi 
> ---
>  drivers/acpi/nfit.c  |  8 +++-
>  drivers/nvdimm/region_devs.c | 26 +-
>  include/linux/libnvdimm.h|  2 ++
>  3 files changed, 34 insertions(+), 2 deletions(-)
>

I don't think we need "nd_vcd_device_type".  I think this patch can
just be reduced to:

diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
index 32579a7b71d5..d289e772c20a 100644
--- a/drivers/acpi/nfit.c
+++ b/drivers/acpi/nfit.c
@@ -1948,6 +1948,7 @@ static int acpi_nfit_init_mapping(struct
acpi_nfit_desc *acpi_desc,
nd_mapping->nvdimm = nvdimm;
switch (nfit_spa_type(spa)) {
case NFIT_SPA_PM:
+   case NFIT_SPA_VCD:
case NFIT_SPA_VOLATILE:
nd_mapping->start = memdev->address;
nd_mapping->size = memdev->region_size;

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

2016-06-24 Thread Dan Williams

On Fri, Jun 24, 2016 at 12:51 AM, Lee, Chun-Yi  wrote:
> This patch adds logic to treat volatile virtual CD region as pmem
> region, then /dev/pmem* device can be mounted with iso9660.
>
> It's useful to work with the httpboot in EFI firmware to pull a remote
> ISO file to the local memory region for booting and installation.
>
> Wiki page of UEFI HTTPBoot with OVMF:
> https://en.opensuse.org/UEFI_HTTPBoot_with_OVMF
>
> The ramdisk function in EDK2/OVMF generates a ACPI0012 root device that
> it contains empty _STA but without _DSM:
>
> DefinitionBlock ("ssdt2.aml", "SSDT", 2, "INTEL ", "RamDisk ", 0x1000)
> {
> Scope (\_SB)
> {
> Device (NVDR)
> {
> Name (_HID, "ACPI0012")  // _HID: Hardware ID
> Name (_STR, Unicode ("NVDIMM Root Device"))  // _STR: Description 
> String
> Method (_STA, 0, NotSerialized)  // _STA: Status
> {
> Return (0x0F)
> }
> }
> }
> }
>
> In section 5.2.25.2 of ACPI 6.1 spec, it mentions that the "SPA Range
> Structure Index" of VCD SPA shall be set to zero. That means VCD SPA
> will not be associated by any NVDIMM region mapping.
>
> The VCD's SPA Range Structure in NFIT is similar to virtual disk region
> as following:
>
> [028h 0040   2]Subtable Type :  [System Physical Address 
> Range]
> [02Ah 0042   2]   Length : 0038
>
> [02Ch 0044   2]  Range Index : 
> [02Eh 0046   2]Flags (decoded below) : 
>Add/Online Operation Only : 0
>   Proximity Domain Valid : 0
> [030h 0048   4] Reserved : 
> [034h 0052   4] Proximity Domain : 
> [038h 0056  16]   Address Range GUID : 
> 77AB535A-45FC-624B-5560-F7B281D1F96E
> [048h 0072   8]   Address Range Base : B6ABD018
> [050h 0080   8] Address Range Length : 0550
> [058h 0088   8] Memory Map Attribute : 
>
> The range index set to zero that means the VCD region not associated by
> any NVDIMM region mapping, and it will not assoicate to "flush hint",
> "interleave" or "control region".

No, per the spec zero is a reserved value and we should ignore such
SPA tables.  The way to not associate a SPA range is to never
reference it from a "flush hint", "interleave", or "control region"
table.

>
> After testing on OVMF, pmem driver can support the region that it doesn't
> assoicate to any NVDIMM mapping. So, treat VCD as pmem is a idea to get
> a pmem block device that it containts iso.
>
> v2
> Removed the code for setting VCD to a read-only region.
>
> Cc: Gary Lin 
> Cc: Dan Williams 
> Cc: Ross Zwisler 
> Cc: "Rafael J. Wysocki" 
> Cc: Linda Knippers 
> Signed-off-by: Lee, Chun-Yi 
> ---
>  drivers/acpi/nfit.c  |  8 +++-
>  drivers/nvdimm/region_devs.c | 26 +-
>  include/linux/libnvdimm.h|  2 ++
>  3 files changed, 34 insertions(+), 2 deletions(-)
>

I don't think we need "nd_vcd_device_type".  I think this patch can
just be reduced to:

diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
index 32579a7b71d5..d289e772c20a 100644
--- a/drivers/acpi/nfit.c
+++ b/drivers/acpi/nfit.c
@@ -1948,6 +1948,7 @@ static int acpi_nfit_init_mapping(struct
acpi_nfit_desc *acpi_desc,
nd_mapping->nvdimm = nvdimm;
switch (nfit_spa_type(spa)) {
case NFIT_SPA_PM:
+   case NFIT_SPA_VCD:
case NFIT_SPA_VOLATILE:
nd_mapping->start = memdev->address;
nd_mapping->size = memdev->region_size;

[PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

2016-06-24 Thread Lee, Chun-Yi

This patch adds logic to treat volatile virtual CD region as pmem
region, then /dev/pmem* device can be mounted with iso9660.

It's useful to work with the httpboot in EFI firmware to pull a remote
ISO file to the local memory region for booting and installation.

Wiki page of UEFI HTTPBoot with OVMF:
https://en.opensuse.org/UEFI_HTTPBoot_with_OVMF

The ramdisk function in EDK2/OVMF generates a ACPI0012 root device that
it contains empty _STA but without _DSM:

DefinitionBlock ("ssdt2.aml", "SSDT", 2, "INTEL ", "RamDisk ", 0x1000)
{
Scope (\_SB)
{
Device (NVDR)
{
Name (_HID, "ACPI0012")  // _HID: Hardware ID
Name (_STR, Unicode ("NVDIMM Root Device"))  // _STR: Description 
String
Method (_STA, 0, NotSerialized)  // _STA: Status
{
Return (0x0F)
}
}
}
}

In section 5.2.25.2 of ACPI 6.1 spec, it mentions that the "SPA Range
Structure Index" of VCD SPA shall be set to zero. That means VCD SPA
will not be associated by any NVDIMM region mapping.

The VCD's SPA Range Structure in NFIT is similar to virtual disk region
as following:

[028h 0040   2]Subtable Type :  [System Physical Address 
Range]
[02Ah 0042   2]   Length : 0038

[02Ch 0044   2]  Range Index : 
[02Eh 0046   2]Flags (decoded below) : 
   Add/Online Operation Only : 0
  Proximity Domain Valid : 0
[030h 0048   4] Reserved : 
[034h 0052   4] Proximity Domain : 
[038h 0056  16]   Address Range GUID : 
77AB535A-45FC-624B-5560-F7B281D1F96E
[048h 0072   8]   Address Range Base : B6ABD018
[050h 0080   8] Address Range Length : 0550
[058h 0088   8] Memory Map Attribute : 

The range index set to zero that means the VCD region not associated by
any NVDIMM region mapping, and it will not assoicate to "flush hint",
"interleave" or "control region".

After testing on OVMF, pmem driver can support the region that it doesn't
assoicate to any NVDIMM mapping. So, treat VCD as pmem is a idea to get
a pmem block device that it containts iso. 
 
v2
Removed the code for setting VCD to a read-only region.

Cc: Gary Lin 
Cc: Dan Williams 
Cc: Ross Zwisler 
Cc: "Rafael J. Wysocki" 
Cc: Linda Knippers 
Signed-off-by: Lee, Chun-Yi 
---
 drivers/acpi/nfit.c  |  8 +++-
 drivers/nvdimm/region_devs.c | 26 +-
 include/linux/libnvdimm.h|  2 ++
 3 files changed, 34 insertions(+), 2 deletions(-)

Index: linux/drivers/acpi/nfit.c
===
--- linux.orig/drivers/acpi/nfit.c
+++ linux/drivers/acpi/nfit.c
@@ -1995,7 +1995,7 @@ static int acpi_nfit_register_region(str
if (nfit_spa->nd_region)
return 0;
 
-   if (spa->range_index == 0) {
+   if (spa->range_index == 0 && nfit_spa_type(spa) != NFIT_SPA_VCD) {
dev_dbg(acpi_desc->dev, "%s: detected invalid spa index\n",
__func__);
return 0;
@@ -2059,6 +2059,11 @@ static int acpi_nfit_register_region(str
ndr_desc);
if (!nfit_spa->nd_region)
rc = -ENOMEM;
+   } else if (nfit_spa_type(spa) == NFIT_SPA_VCD) {
+   nfit_spa->nd_region = nvdimm_vcd_region_create(nvdimm_bus,
+   ndr_desc);
+   if (!nfit_spa->nd_region)
+   rc = -ENOMEM;
}
 
  out:
Index: linux/drivers/nvdimm/region_devs.c
===
--- linux.orig/drivers/nvdimm/region_devs.c
+++ linux/drivers/nvdimm/region_devs.c
@@ -56,9 +56,19 @@ static struct device_type nd_volatile_de
.release = nd_region_release,
 };
 
+static struct device_type nd_vcd_device_type = {
+   .name = "nd_vcd",
+   .release = nd_region_release,
+};
+
+bool is_nd_vcd(struct device *dev)
+{
+   return dev ? dev->type == _vcd_device_type : false;
+}
+
 bool is_nd_pmem(struct device *dev)
 {
-   return dev ? dev->type == _pmem_device_type : false;
+   return dev ? dev->type == _pmem_device_type || is_nd_vcd(dev) : 
false;
 }
 
 bool is_nd_blk(struct device *dev)
@@ -774,6 +784,14 @@ struct nd_region *nvdimm_pmem_region_cre
 }
 EXPORT_SYMBOL_GPL(nvdimm_pmem_region_create);
 
+struct nd_region *nvdimm_vcd_region_create(struct nvdimm_bus *nvdimm_bus,
+   struct nd_region_desc *ndr_desc)
+{
+   return nd_region_create(nvdimm_bus, ndr_desc, _vcd_device_type,
+   __func__);
+}
+EXPORT_SYMBOL_GPL(nvdimm_vcd_region_create);
+
 struct nd_region *nvdimm_blk_region_create(struct nvdimm_bus

[PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

2016-06-24 Thread Lee, Chun-Yi

This patch adds logic to treat volatile virtual CD region as pmem
region, then /dev/pmem* device can be mounted with iso9660.

It's useful to work with the httpboot in EFI firmware to pull a remote
ISO file to the local memory region for booting and installation.

Wiki page of UEFI HTTPBoot with OVMF:
https://en.opensuse.org/UEFI_HTTPBoot_with_OVMF

The ramdisk function in EDK2/OVMF generates a ACPI0012 root device that
it contains empty _STA but without _DSM:

DefinitionBlock ("ssdt2.aml", "SSDT", 2, "INTEL ", "RamDisk ", 0x1000)
{
Scope (\_SB)
{
Device (NVDR)
{
Name (_HID, "ACPI0012")  // _HID: Hardware ID
Name (_STR, Unicode ("NVDIMM Root Device"))  // _STR: Description 
String
Method (_STA, 0, NotSerialized)  // _STA: Status
{
Return (0x0F)
}
}
}
}

In section 5.2.25.2 of ACPI 6.1 spec, it mentions that the "SPA Range
Structure Index" of VCD SPA shall be set to zero. That means VCD SPA
will not be associated by any NVDIMM region mapping.

The VCD's SPA Range Structure in NFIT is similar to virtual disk region
as following:

[028h 0040   2]Subtable Type :  [System Physical Address 
Range]
[02Ah 0042   2]   Length : 0038

[02Ch 0044   2]  Range Index : 
[02Eh 0046   2]Flags (decoded below) : 
   Add/Online Operation Only : 0
  Proximity Domain Valid : 0
[030h 0048   4] Reserved : 
[034h 0052   4] Proximity Domain : 
[038h 0056  16]   Address Range GUID : 
77AB535A-45FC-624B-5560-F7B281D1F96E
[048h 0072   8]   Address Range Base : B6ABD018
[050h 0080   8] Address Range Length : 0550
[058h 0088   8] Memory Map Attribute : 

The range index set to zero that means the VCD region not associated by
any NVDIMM region mapping, and it will not assoicate to "flush hint",
"interleave" or "control region".

After testing on OVMF, pmem driver can support the region that it doesn't
assoicate to any NVDIMM mapping. So, treat VCD as pmem is a idea to get
a pmem block device that it containts iso. 
 
v2
Removed the code for setting VCD to a read-only region.

Cc: Gary Lin 
Cc: Dan Williams 
Cc: Ross Zwisler 
Cc: "Rafael J. Wysocki" 
Cc: Linda Knippers 
Signed-off-by: Lee, Chun-Yi 
---
 drivers/acpi/nfit.c  |  8 +++-
 drivers/nvdimm/region_devs.c | 26 +-
 include/linux/libnvdimm.h|  2 ++
 3 files changed, 34 insertions(+), 2 deletions(-)

Index: linux/drivers/acpi/nfit.c
===
--- linux.orig/drivers/acpi/nfit.c
+++ linux/drivers/acpi/nfit.c
@@ -1995,7 +1995,7 @@ static int acpi_nfit_register_region(str
if (nfit_spa->nd_region)
return 0;
 
-   if (spa->range_index == 0) {
+   if (spa->range_index == 0 && nfit_spa_type(spa) != NFIT_SPA_VCD) {
dev_dbg(acpi_desc->dev, "%s: detected invalid spa index\n",
__func__);
return 0;
@@ -2059,6 +2059,11 @@ static int acpi_nfit_register_region(str
ndr_desc);
if (!nfit_spa->nd_region)
rc = -ENOMEM;
+   } else if (nfit_spa_type(spa) == NFIT_SPA_VCD) {
+   nfit_spa->nd_region = nvdimm_vcd_region_create(nvdimm_bus,
+   ndr_desc);
+   if (!nfit_spa->nd_region)
+   rc = -ENOMEM;
}
 
  out:
Index: linux/drivers/nvdimm/region_devs.c
===
--- linux.orig/drivers/nvdimm/region_devs.c
+++ linux/drivers/nvdimm/region_devs.c
@@ -56,9 +56,19 @@ static struct device_type nd_volatile_de
.release = nd_region_release,
 };
 
+static struct device_type nd_vcd_device_type = {
+   .name = "nd_vcd",
+   .release = nd_region_release,
+};
+
+bool is_nd_vcd(struct device *dev)
+{
+   return dev ? dev->type == _vcd_device_type : false;
+}
+
 bool is_nd_pmem(struct device *dev)
 {
-   return dev ? dev->type == _pmem_device_type : false;
+   return dev ? dev->type == _pmem_device_type || is_nd_vcd(dev) : 
false;
 }
 
 bool is_nd_blk(struct device *dev)
@@ -774,6 +784,14 @@ struct nd_region *nvdimm_pmem_region_cre
 }
 EXPORT_SYMBOL_GPL(nvdimm_pmem_region_create);
 
+struct nd_region *nvdimm_vcd_region_create(struct nvdimm_bus *nvdimm_bus,
+   struct nd_region_desc *ndr_desc)
+{
+   return nd_region_create(nvdimm_bus, ndr_desc, _vcd_device_type,
+   __func__);
+}
+EXPORT_SYMBOL_GPL(nvdimm_vcd_region_create);
+
 struct nd_region *nvdimm_blk_region_create(struct nvdimm_bus *nvdimm_bus,
struct nd_region_desc *ndr_desc)
 {
Index: linux/include/linux/libnvdimm.h

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

Re: [PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

[PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

[PATCH v2] libnvdimm, nfit: treat volatile virtual CD region as pmem

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