Re: [PULL 32/56] hw/block/nvme: split setup and register for namespace

[Philippe Mathieu-Daudé]

On 2/11/21 10:53 AM, Alexander Graf wrote:
> Hi Klaus,
> 
> On 09.02.21 08:30, Klaus Jensen wrote:
>> From: Minwoo Im <minwoo.im.dev@gmail.com>
>>
>> In NVMe, namespace is being attached to process I/O.  We register NVMe
>> namespace to a controller via nvme_register_namespace() during
>> nvme_ns_setup().  This is main reason of receiving NvmeCtrl object
>> instance to this function to map the namespace to a controller.
>>
>> To make namespace instance more independent, it should be split into two
>> parts: setup and register.  This patch split them into two differnt
>> parts, and finally nvme_ns_setup() does not have nothing to do with
>> NvmeCtrl instance at all.
>>
>> This patch is a former patch to introduce NVMe subsystem scheme to the
>> existing design especially for multi-path.  In that case, it should be
>> split into two to make namespace independent from a controller.
>>
>> Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
>> Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
> 
> 
> In latest master, I can no longer access NVMe devices from edk2. Git
> bisect pointed me to this commit.
> 
> To reproduce:
> 
>   $ ./build/qemu-system-x86_64 -enable-kvm -pflash
> build/pc-bios/edk2-x86_64-code.fd -drive
> file=image.raw,if=none,id=d,snapshot=on -device nvme,serial=1234,drive=d
> -nographic -net none
> 
> You will see that before this commit, edk2 is able to enumerate the
> block device, while after this commit it does not find it.
> 
> 
> good:
> 
> Mapping table
>       FS0: Alias(s):HD1b:;BLK2:
>         �
> PciRoot(0x0)/Pci(0x3,0x0)/NVMe(0x1,00-00-00-00-00-00-00-00)/HD(1,GPT,7A866FF6-0A12-4911-A4ED-D0565BEB41A2,0x80,0x64000)
> 
>      BLK0: Alias(s):
>           PciRoot(0x0)/Pci(0x1,0x1)/Ata(0x0)
>      BLK1: Alias(s):
>         � PciRoot(0x0)/Pci(0x3,0x0)/NVMe(0x1,00-00-00-00-00-00-00-00)
>      BLK3: Alias(s):
>         �
> PciRoot(0x0)/Pci(0x3,0x0)/NVMe(0x1,00-00-00-00-00-00-00-00)/HD(2,GPT,F070566B-C58D-4F13-9B92-64F1794385E7,0x64080,0x40000)
> 
>      BLK4: Alias(s):
>         �
> PciRoot(0x0)/Pci(0x3,0x0)/NVMe(0x1,00-00-00-00-00-00-00-00)/HD(3,GPT,EDE86BE3-C64F-4ACB-B4AA-5E6C0135D335,0xA4080,0x315BF1B)

Good integration test for the emulated NVMe subsystem!

tests/acceptance/boot_linux_console.py should provide trivial template.

> 
> 
> 
> bad:
> 
> Mapping table
>      BLK0: Alias(s):
>           PciRoot(0x0)/Pci(0x1,0x1)/Ata(0x0)
> 
> 
> 
> Thanks,
> 
> Alex
> 
> 
>