| Message ID | 20210117145341.23310-1-minwoo.im.dev@gmail.com |
|---|---|
| Headers | show |
| Series | hw/block/nvme: support multi-path for ctrl/ns | expand |
On Jan 17 23:53, Minwoo Im wrote: > Hello, > > This patch series introduces NVMe subsystem device to support multi-path > I/O in NVMe device model. Two use-cases are supported along with this > patch: Multi-controller, Namespace Sharing. > > V1 RFC has been discussed with Klaus and Keith, I really appreciate them > for this patch series to have proper direction [1]. > > This patch series contains few start-up refactoring pathces from the > first to fifth patches to make nvme-ns device not to rely on the nvme > controller always. Because nvme-ns shall be able to be mapped to the > subsystem level, not a single controller level so that it should provide > generic initialization code: nvme_ns_setup() with NvmeCtrl. To do that, > the first five patches are to remove the NvmeCtrl * instance argument > from the nvme_ns_setup(). I'd be happy if they are picked! > > For controller and namespace devices, 'subsys' property has been > introduced to map them to a subsystem. If multi-controller needed, we > can specify 'subsys' to controllers the same. > > For namespace deivice, if 'subsys' is not given just like it was, it > will have to be provided with 'bus' parameter to specify a nvme > controller device to attach, it means, they are mutual-exlusive. To > share a namespace between or among controllers, then nvme-ns should have > 'subsys' property to a single nvme subsystem instance. To make a > namespace private one, then we need to specify 'bus' property rather > than the 'subsys'. > > Of course, this series does not require any updates for the run command > for the previos users. > > Plase refer the following example with nvme-cli output: > > QEMU Run: > -device nvme-subsys,id=subsys0 \ > -device nvme,serial=foo,id=nvme0,subsys=subsys0 \ > -device nvme,serial=bar,id=nvme1,subsys=subsys0 \ > -device nvme,serial=baz,id=nvme2,subsys=subsys0 \ > -device nvme-ns,id=ns1,drive=drv10,nsid=1,subsys=subsys0 \ > -device nvme-ns,id=ns2,drive=drv11,nsid=2,bus=nvme2 \ > \ > -device nvme,serial=qux,id=nvme3 \ > -device nvme-ns,id=ns3,drive=drv12,nsid=3,bus=nvme3 > > nvme-cli: > root@vm:~/work# nvme list -v > NVM Express Subsystems > > Subsystem Subsystem-NQN Controllers > ---------------- ------------------------------------------------------------------------------------------------ ---------------- > nvme-subsys1 nqn.2019-08.org.qemu:subsys0 nvme0, nvme1, nvme2 > nvme-subsys3 nqn.2019-08.org.qemu:qux nvme3 > > NVM Express Controllers > > Device SN MN FR TxPort Address Subsystem Namespaces > -------- -------------------- ---------------------------------------- -------- ------ -------------- ------------ ---------------- > nvme0 foo QEMU NVMe Ctrl 1.0 pcie 0000:00:06.0 nvme-subsys1 nvme1n1 > nvme1 bar QEMU NVMe Ctrl 1.0 pcie 0000:00:07.0 nvme-subsys1 nvme1n1 > nvme2 baz QEMU NVMe Ctrl 1.0 pcie 0000:00:08.0 nvme-subsys1 nvme1n1, nvme1n2 > nvme3 qux QEMU NVMe Ctrl 1.0 pcie 0000:00:09.0 nvme-subsys3 > > NVM Express Namespaces > > Device NSID Usage Format Controllers > ------------ -------- -------------------------- ---------------- ---------------- > nvme1n1 1 134.22 MB / 134.22 MB 512 B + 0 B nvme0, nvme1, nvme2 > nvme1n2 2 268.44 MB / 268.44 MB 512 B + 0 B nvme2 > nvme3n1 3 268.44 MB / 268.44 MB 512 B + 0 B nvme3 > > Summary: > - Refactored nvme-ns device not to rely on controller during the > setup. [1/11 - 5/11] > - Introduced a nvme-subsys device model. [6/11] > - Create subsystem NQN based on subsystem. [7/11] > - Introduced multi-controller model. [8/11 - 9/11] > - Updated namespace sharing scheme to be based on nvme-subsys > hierarchy. [10/11 - 11/11] > > Since RFC V1: > - Updated namespace sharing scheme to be based on nvme-subsys > hierarchy. > Great stuff Minwoo. Thanks! I'll pick up [01-05/11] directly since they are pretty trivial. The subsystem model looks pretty much like it should, I don't have a lot of comments. One thing that I considered, is if we should reverse the "registration" and think about it as namespace attachment. The spec is about controllers attaching to namespaces, not the other way around. Basically, let the namespaces be configured first and register on the subsystem (accumulating in a "namespaces" array), then have the controllers register with the subsystem and attach to all "non-detached" namespaces. This allows detached namespaces to "linger" in the subsystem to be attached later on. If there are any private namespaces (like ns2 in your example above), it will be defined after the controller with the bus=ctrlX parameter like normal.
On 21-01-18 22:14:45, Klaus Jensen wrote: > On Jan 17 23:53, Minwoo Im wrote: > > Hello, > > > > This patch series introduces NVMe subsystem device to support multi-path > > I/O in NVMe device model. Two use-cases are supported along with this > > patch: Multi-controller, Namespace Sharing. > > > > V1 RFC has been discussed with Klaus and Keith, I really appreciate them > > for this patch series to have proper direction [1]. > > > > This patch series contains few start-up refactoring pathces from the > > first to fifth patches to make nvme-ns device not to rely on the nvme > > controller always. Because nvme-ns shall be able to be mapped to the > > subsystem level, not a single controller level so that it should provide > > generic initialization code: nvme_ns_setup() with NvmeCtrl. To do that, > > the first five patches are to remove the NvmeCtrl * instance argument > > from the nvme_ns_setup(). I'd be happy if they are picked! > > > > For controller and namespace devices, 'subsys' property has been > > introduced to map them to a subsystem. If multi-controller needed, we > > can specify 'subsys' to controllers the same. > > > > For namespace deivice, if 'subsys' is not given just like it was, it > > will have to be provided with 'bus' parameter to specify a nvme > > controller device to attach, it means, they are mutual-exlusive. To > > share a namespace between or among controllers, then nvme-ns should have > > 'subsys' property to a single nvme subsystem instance. To make a > > namespace private one, then we need to specify 'bus' property rather > > than the 'subsys'. > > > > Of course, this series does not require any updates for the run command > > for the previos users. > > > > Plase refer the following example with nvme-cli output: > > > > QEMU Run: > > -device nvme-subsys,id=subsys0 \ > > -device nvme,serial=foo,id=nvme0,subsys=subsys0 \ > > -device nvme,serial=bar,id=nvme1,subsys=subsys0 \ > > -device nvme,serial=baz,id=nvme2,subsys=subsys0 \ > > -device nvme-ns,id=ns1,drive=drv10,nsid=1,subsys=subsys0 \ > > -device nvme-ns,id=ns2,drive=drv11,nsid=2,bus=nvme2 \ > > \ > > -device nvme,serial=qux,id=nvme3 \ > > -device nvme-ns,id=ns3,drive=drv12,nsid=3,bus=nvme3 > > > > nvme-cli: > > root@vm:~/work# nvme list -v > > NVM Express Subsystems > > > > Subsystem Subsystem-NQN Controllers > > ---------------- ------------------------------------------------------------------------------------------------ ---------------- > > nvme-subsys1 nqn.2019-08.org.qemu:subsys0 nvme0, nvme1, nvme2 > > nvme-subsys3 nqn.2019-08.org.qemu:qux nvme3 > > > > NVM Express Controllers > > > > Device SN MN FR TxPort Address Subsystem Namespaces > > -------- -------------------- ---------------------------------------- -------- ------ -------------- ------------ ---------------- > > nvme0 foo QEMU NVMe Ctrl 1.0 pcie 0000:00:06.0 nvme-subsys1 nvme1n1 > > nvme1 bar QEMU NVMe Ctrl 1.0 pcie 0000:00:07.0 nvme-subsys1 nvme1n1 > > nvme2 baz QEMU NVMe Ctrl 1.0 pcie 0000:00:08.0 nvme-subsys1 nvme1n1, nvme1n2 > > nvme3 qux QEMU NVMe Ctrl 1.0 pcie 0000:00:09.0 nvme-subsys3 > > > > NVM Express Namespaces > > > > Device NSID Usage Format Controllers > > ------------ -------- -------------------------- ---------------- ---------------- > > nvme1n1 1 134.22 MB / 134.22 MB 512 B + 0 B nvme0, nvme1, nvme2 > > nvme1n2 2 268.44 MB / 268.44 MB 512 B + 0 B nvme2 > > nvme3n1 3 268.44 MB / 268.44 MB 512 B + 0 B nvme3 > > > > Summary: > > - Refactored nvme-ns device not to rely on controller during the > > setup. [1/11 - 5/11] > > - Introduced a nvme-subsys device model. [6/11] > > - Create subsystem NQN based on subsystem. [7/11] > > - Introduced multi-controller model. [8/11 - 9/11] > > - Updated namespace sharing scheme to be based on nvme-subsys > > hierarchy. [10/11 - 11/11] > > > > Since RFC V1: > > - Updated namespace sharing scheme to be based on nvme-subsys > > hierarchy. > > > > Great stuff Minwoo. Thanks! > > I'll pick up [01-05/11] directly since they are pretty trivial. Thanks! will prepare the next series based on there. > The subsystem model looks pretty much like it should, I don't have a lot > of comments. > > One thing that I considered, is if we should reverse the "registration" > and think about it as namespace attachment. The spec is about > controllers attaching to namespaces, not the other way around. > Basically, let the namespaces be configured first and register on the > subsystem (accumulating in a "namespaces" array), then have the > controllers register with the subsystem and attach to all "non-detached" > namespaces. This allows detached namespaces to "linger" in the subsystem > to be attached later on. If there are any private namespaces (like ns2 > in your example above), it will be defined after the controller with the > bus=ctrlX parameter like normal. Revisited spec. again. 5.19 says "The Namespace Attachment command is used to attach and detach controllers from a namespace.". and 5.20 says "Host software uses the Namespace Attachment command to attach or detach a namespace to or from a controller. The create operation does not attach the namespace to a controller." -device nvme-subsys,id=subsys0 -device nvme-ns,id=ns1,drive=<drv>,nsid=1,subsys=subsys0 -device nvme,id=nvme0,serial=foo,subsys=subsys0 In this case, the 'nvme0' controller will have no namespace at the initial time of the boot-up. 'nvme0' can be attached to the namespace 'ns1' with namespace attach command. 'nvme-ns' device is same as the 'create-ns' operation in a NVMe subsystem. This makes sense as spec 5.19 says "from a namespace". -device nvme,id=nvme1,serial=bar,subsys=subsys0b -device nvme-ns,id=ns2,drive=<drv>,nsid=1,bus=nvme1 This case if for private namespace directly attached to controller. This makes sense as spec 5.20 says "to or from a controller". All looks fine to me, but one thing I an wondering is that how can we attach a controller to shared namespace(s) at the initial time?
On Jan 19 12:21, Minwoo Im wrote: > On 21-01-18 22:14:45, Klaus Jensen wrote: > > On Jan 17 23:53, Minwoo Im wrote: > > > Hello, > > > > > > This patch series introduces NVMe subsystem device to support multi-path > > > I/O in NVMe device model. Two use-cases are supported along with this > > > patch: Multi-controller, Namespace Sharing. > > > > > > V1 RFC has been discussed with Klaus and Keith, I really appreciate them > > > for this patch series to have proper direction [1]. > > > > > > This patch series contains few start-up refactoring pathces from the > > > first to fifth patches to make nvme-ns device not to rely on the nvme > > > controller always. Because nvme-ns shall be able to be mapped to the > > > subsystem level, not a single controller level so that it should provide > > > generic initialization code: nvme_ns_setup() with NvmeCtrl. To do that, > > > the first five patches are to remove the NvmeCtrl * instance argument > > > from the nvme_ns_setup(). I'd be happy if they are picked! > > > > > > For controller and namespace devices, 'subsys' property has been > > > introduced to map them to a subsystem. If multi-controller needed, we > > > can specify 'subsys' to controllers the same. > > > > > > For namespace deivice, if 'subsys' is not given just like it was, it > > > will have to be provided with 'bus' parameter to specify a nvme > > > controller device to attach, it means, they are mutual-exlusive. To > > > share a namespace between or among controllers, then nvme-ns should have > > > 'subsys' property to a single nvme subsystem instance. To make a > > > namespace private one, then we need to specify 'bus' property rather > > > than the 'subsys'. > > > > > > Of course, this series does not require any updates for the run command > > > for the previos users. > > > > > > Plase refer the following example with nvme-cli output: > > > > > > QEMU Run: > > > -device nvme-subsys,id=subsys0 \ > > > -device nvme,serial=foo,id=nvme0,subsys=subsys0 \ > > > -device nvme,serial=bar,id=nvme1,subsys=subsys0 \ > > > -device nvme,serial=baz,id=nvme2,subsys=subsys0 \ > > > -device nvme-ns,id=ns1,drive=drv10,nsid=1,subsys=subsys0 \ > > > -device nvme-ns,id=ns2,drive=drv11,nsid=2,bus=nvme2 \ > > > \ > > > -device nvme,serial=qux,id=nvme3 \ > > > -device nvme-ns,id=ns3,drive=drv12,nsid=3,bus=nvme3 > > > > > > nvme-cli: > > > root@vm:~/work# nvme list -v > > > NVM Express Subsystems > > > > > > Subsystem Subsystem-NQN Controllers > > > ---------------- ------------------------------------------------------------------------------------------------ ---------------- > > > nvme-subsys1 nqn.2019-08.org.qemu:subsys0 nvme0, nvme1, nvme2 > > > nvme-subsys3 nqn.2019-08.org.qemu:qux nvme3 > > > > > > NVM Express Controllers > > > > > > Device SN MN FR TxPort Address Subsystem Namespaces > > > -------- -------------------- ---------------------------------------- -------- ------ -------------- ------------ ---------------- > > > nvme0 foo QEMU NVMe Ctrl 1.0 pcie 0000:00:06.0 nvme-subsys1 nvme1n1 > > > nvme1 bar QEMU NVMe Ctrl 1.0 pcie 0000:00:07.0 nvme-subsys1 nvme1n1 > > > nvme2 baz QEMU NVMe Ctrl 1.0 pcie 0000:00:08.0 nvme-subsys1 nvme1n1, nvme1n2 > > > nvme3 qux QEMU NVMe Ctrl 1.0 pcie 0000:00:09.0 nvme-subsys3 > > > > > > NVM Express Namespaces > > > > > > Device NSID Usage Format Controllers > > > ------------ -------- -------------------------- ---------------- ---------------- > > > nvme1n1 1 134.22 MB / 134.22 MB 512 B + 0 B nvme0, nvme1, nvme2 > > > nvme1n2 2 268.44 MB / 268.44 MB 512 B + 0 B nvme2 > > > nvme3n1 3 268.44 MB / 268.44 MB 512 B + 0 B nvme3 > > > > > > Summary: > > > - Refactored nvme-ns device not to rely on controller during the > > > setup. [1/11 - 5/11] > > > - Introduced a nvme-subsys device model. [6/11] > > > - Create subsystem NQN based on subsystem. [7/11] > > > - Introduced multi-controller model. [8/11 - 9/11] > > > - Updated namespace sharing scheme to be based on nvme-subsys > > > hierarchy. [10/11 - 11/11] > > > > > > Since RFC V1: > > > - Updated namespace sharing scheme to be based on nvme-subsys > > > hierarchy. > > > > > > > Great stuff Minwoo. Thanks! > > > > I'll pick up [01-05/11] directly since they are pretty trivial. > > Thanks! will prepare the next series based on there. > > > The subsystem model looks pretty much like it should, I don't have a lot > > of comments. > > > > One thing that I considered, is if we should reverse the "registration" > > and think about it as namespace attachment. The spec is about > > controllers attaching to namespaces, not the other way around. > > Basically, let the namespaces be configured first and register on the > > subsystem (accumulating in a "namespaces" array), then have the > > controllers register with the subsystem and attach to all "non-detached" > > namespaces. This allows detached namespaces to "linger" in the subsystem > > to be attached later on. If there are any private namespaces (like ns2 > > in your example above), it will be defined after the controller with the > > bus=ctrlX parameter like normal. > > Revisited spec. again. 5.19 says "The Namespace Attachment command is > used to attach and detach controllers from a namespace.". and 5.20 says > "Host software uses the Namespace Attachment command to attach or detach > a namespace to or from a controller. The create operation does not attach > the namespace to a controller." > Yeah ok, that is pretty inconsistent. > -device nvme-subsys,id=subsys0 > -device nvme-ns,id=ns1,drive=<drv>,nsid=1,subsys=subsys0 > -device nvme,id=nvme0,serial=foo,subsys=subsys0 > > In this case, the 'nvme0' controller will have no namespace at the > initial time of the boot-up. 'nvme0' can be attached to the namespace > 'ns1' with namespace attach command. 'nvme-ns' device is same as the > 'create-ns' operation in a NVMe subsystem. This makes sense as spec > 5.19 says "from a namespace". > > -device nvme,id=nvme1,serial=bar,subsys=subsys0b > -device nvme-ns,id=ns2,drive=<drv>,nsid=1,bus=nvme1 > > This case if for private namespace directly attached to controller. > This makes sense as spec 5.20 says "to or from a controller". > > All looks fine to me, but one thing I an wondering is that how can we > attach a controller to shared namespace(s) at the initial time? > Ok, nevermind. I think we can get 'detached' functionality in either case, so no need to increase complexity by requiring a change of define order. Supporting CNS 0x12 and 0x13 (Identify, Controller List), we need the controllers registered and stored in the subsystem anyway. So, can we add a 'namespaces' array on the subsystem to keep a list of namespaces and add a 'detached' parameter on the nvme-ns device? If that parameter is given, the device is not registered with the controllers.
On 21-01-19 07:04:04, Klaus Jensen wrote: > On Jan 19 12:21, Minwoo Im wrote: > > On 21-01-18 22:14:45, Klaus Jensen wrote: > > > On Jan 17 23:53, Minwoo Im wrote: > > > > Hello, > > > > > > > > This patch series introduces NVMe subsystem device to support multi-path > > > > I/O in NVMe device model. Two use-cases are supported along with this > > > > patch: Multi-controller, Namespace Sharing. > > > > > > > > V1 RFC has been discussed with Klaus and Keith, I really appreciate them > > > > for this patch series to have proper direction [1]. > > > > > > > > This patch series contains few start-up refactoring pathces from the > > > > first to fifth patches to make nvme-ns device not to rely on the nvme > > > > controller always. Because nvme-ns shall be able to be mapped to the > > > > subsystem level, not a single controller level so that it should provide > > > > generic initialization code: nvme_ns_setup() with NvmeCtrl. To do that, > > > > the first five patches are to remove the NvmeCtrl * instance argument > > > > from the nvme_ns_setup(). I'd be happy if they are picked! > > > > > > > > For controller and namespace devices, 'subsys' property has been > > > > introduced to map them to a subsystem. If multi-controller needed, we > > > > can specify 'subsys' to controllers the same. > > > > > > > > For namespace deivice, if 'subsys' is not given just like it was, it > > > > will have to be provided with 'bus' parameter to specify a nvme > > > > controller device to attach, it means, they are mutual-exlusive. To > > > > share a namespace between or among controllers, then nvme-ns should have > > > > 'subsys' property to a single nvme subsystem instance. To make a > > > > namespace private one, then we need to specify 'bus' property rather > > > > than the 'subsys'. > > > > > > > > Of course, this series does not require any updates for the run command > > > > for the previos users. > > > > > > > > Plase refer the following example with nvme-cli output: > > > > > > > > QEMU Run: > > > > -device nvme-subsys,id=subsys0 \ > > > > -device nvme,serial=foo,id=nvme0,subsys=subsys0 \ > > > > -device nvme,serial=bar,id=nvme1,subsys=subsys0 \ > > > > -device nvme,serial=baz,id=nvme2,subsys=subsys0 \ > > > > -device nvme-ns,id=ns1,drive=drv10,nsid=1,subsys=subsys0 \ > > > > -device nvme-ns,id=ns2,drive=drv11,nsid=2,bus=nvme2 \ > > > > \ > > > > -device nvme,serial=qux,id=nvme3 \ > > > > -device nvme-ns,id=ns3,drive=drv12,nsid=3,bus=nvme3 > > > > > > > > nvme-cli: > > > > root@vm:~/work# nvme list -v > > > > NVM Express Subsystems > > > > > > > > Subsystem Subsystem-NQN Controllers > > > > ---------------- ------------------------------------------------------------------------------------------------ ---------------- > > > > nvme-subsys1 nqn.2019-08.org.qemu:subsys0 nvme0, nvme1, nvme2 > > > > nvme-subsys3 nqn.2019-08.org.qemu:qux nvme3 > > > > > > > > NVM Express Controllers > > > > > > > > Device SN MN FR TxPort Address Subsystem Namespaces > > > > -------- -------------------- ---------------------------------------- -------- ------ -------------- ------------ ---------------- > > > > nvme0 foo QEMU NVMe Ctrl 1.0 pcie 0000:00:06.0 nvme-subsys1 nvme1n1 > > > > nvme1 bar QEMU NVMe Ctrl 1.0 pcie 0000:00:07.0 nvme-subsys1 nvme1n1 > > > > nvme2 baz QEMU NVMe Ctrl 1.0 pcie 0000:00:08.0 nvme-subsys1 nvme1n1, nvme1n2 > > > > nvme3 qux QEMU NVMe Ctrl 1.0 pcie 0000:00:09.0 nvme-subsys3 > > > > > > > > NVM Express Namespaces > > > > > > > > Device NSID Usage Format Controllers > > > > ------------ -------- -------------------------- ---------------- ---------------- > > > > nvme1n1 1 134.22 MB / 134.22 MB 512 B + 0 B nvme0, nvme1, nvme2 > > > > nvme1n2 2 268.44 MB / 268.44 MB 512 B + 0 B nvme2 > > > > nvme3n1 3 268.44 MB / 268.44 MB 512 B + 0 B nvme3 > > > > > > > > Summary: > > > > - Refactored nvme-ns device not to rely on controller during the > > > > setup. [1/11 - 5/11] > > > > - Introduced a nvme-subsys device model. [6/11] > > > > - Create subsystem NQN based on subsystem. [7/11] > > > > - Introduced multi-controller model. [8/11 - 9/11] > > > > - Updated namespace sharing scheme to be based on nvme-subsys > > > > hierarchy. [10/11 - 11/11] > > > > > > > > Since RFC V1: > > > > - Updated namespace sharing scheme to be based on nvme-subsys > > > > hierarchy. > > > > > > > > > > Great stuff Minwoo. Thanks! > > > > > > I'll pick up [01-05/11] directly since they are pretty trivial. > > > > Thanks! will prepare the next series based on there. > > > > > The subsystem model looks pretty much like it should, I don't have a lot > > > of comments. > > > > > > One thing that I considered, is if we should reverse the "registration" > > > and think about it as namespace attachment. The spec is about > > > controllers attaching to namespaces, not the other way around. > > > Basically, let the namespaces be configured first and register on the > > > subsystem (accumulating in a "namespaces" array), then have the > > > controllers register with the subsystem and attach to all "non-detached" > > > namespaces. This allows detached namespaces to "linger" in the subsystem > > > to be attached later on. If there are any private namespaces (like ns2 > > > in your example above), it will be defined after the controller with the > > > bus=ctrlX parameter like normal. > > > > Revisited spec. again. 5.19 says "The Namespace Attachment command is > > used to attach and detach controllers from a namespace.". and 5.20 says > > "Host software uses the Namespace Attachment command to attach or detach > > a namespace to or from a controller. The create operation does not attach > > the namespace to a controller." > > > > Yeah ok, that is pretty inconsistent. > > > -device nvme-subsys,id=subsys0 > > -device nvme-ns,id=ns1,drive=<drv>,nsid=1,subsys=subsys0 > > -device nvme,id=nvme0,serial=foo,subsys=subsys0 > > > > In this case, the 'nvme0' controller will have no namespace at the > > initial time of the boot-up. 'nvme0' can be attached to the namespace > > 'ns1' with namespace attach command. 'nvme-ns' device is same as the > > 'create-ns' operation in a NVMe subsystem. This makes sense as spec > > 5.19 says "from a namespace". > > > > -device nvme,id=nvme1,serial=bar,subsys=subsys0b > > -device nvme-ns,id=ns2,drive=<drv>,nsid=1,bus=nvme1 > > > > This case if for private namespace directly attached to controller. > > This makes sense as spec 5.20 says "to or from a controller". > > > > All looks fine to me, but one thing I an wondering is that how can we > > attach a controller to shared namespace(s) at the initial time? > > > > Ok, nevermind. I think we can get 'detached' functionality in either > case, so no need to increase complexity by requiring a change of define > order. > > Supporting CNS 0x12 and 0x13 (Identify, Controller List), we need the > controllers registered and stored in the subsystem anyway. > > So, can we add a 'namespaces' array on the subsystem to keep a list of > namespaces and add a 'detached' parameter on the nvme-ns device? If that > parameter is given, the device is not registered with the controllers. Sure, will do that. Plese let me have V3 series. Thanks!
Hello, This patch series introduces NVMe subsystem device to support multi-path I/O in NVMe device model. Two use-cases are supported along with this patch: Multi-controller, Namespace Sharing. V1 RFC has been discussed with Klaus and Keith, I really appreciate them for this patch series to have proper direction [1]. This patch series contains few start-up refactoring pathces from the first to fifth patches to make nvme-ns device not to rely on the nvme controller always. Because nvme-ns shall be able to be mapped to the subsystem level, not a single controller level so that it should provide generic initialization code: nvme_ns_setup() with NvmeCtrl. To do that, the first five patches are to remove the NvmeCtrl * instance argument from the nvme_ns_setup(). I'd be happy if they are picked! For controller and namespace devices, 'subsys' property has been introduced to map them to a subsystem. If multi-controller needed, we can specify 'subsys' to controllers the same. For namespace deivice, if 'subsys' is not given just like it was, it will have to be provided with 'bus' parameter to specify a nvme controller device to attach, it means, they are mutual-exlusive. To share a namespace between or among controllers, then nvme-ns should have 'subsys' property to a single nvme subsystem instance. To make a namespace private one, then we need to specify 'bus' property rather than the 'subsys'. Of course, this series does not require any updates for the run command for the previos users. Plase refer the following example with nvme-cli output: QEMU Run: -device nvme-subsys,id=subsys0 \ -device nvme,serial=foo,id=nvme0,subsys=subsys0 \ -device nvme,serial=bar,id=nvme1,subsys=subsys0 \ -device nvme,serial=baz,id=nvme2,subsys=subsys0 \ -device nvme-ns,id=ns1,drive=drv10,nsid=1,subsys=subsys0 \ -device nvme-ns,id=ns2,drive=drv11,nsid=2,bus=nvme2 \ \ -device nvme,serial=qux,id=nvme3 \ -device nvme-ns,id=ns3,drive=drv12,nsid=3,bus=nvme3 nvme-cli: root@vm:~/work# nvme list -v NVM Express Subsystems Subsystem Subsystem-NQN Controllers ---------------- ------------------------------------------------------------------------------------------------ ---------------- nvme-subsys1 nqn.2019-08.org.qemu:subsys0 nvme0, nvme1, nvme2 nvme-subsys3 nqn.2019-08.org.qemu:qux nvme3 NVM Express Controllers Device SN MN FR TxPort Address Subsystem Namespaces -------- -------------------- ---------------------------------------- -------- ------ -------------- ------------ ---------------- nvme0 foo QEMU NVMe Ctrl 1.0 pcie 0000:00:06.0 nvme-subsys1 nvme1n1 nvme1 bar QEMU NVMe Ctrl 1.0 pcie 0000:00:07.0 nvme-subsys1 nvme1n1 nvme2 baz QEMU NVMe Ctrl 1.0 pcie 0000:00:08.0 nvme-subsys1 nvme1n1, nvme1n2 nvme3 qux QEMU NVMe Ctrl 1.0 pcie 0000:00:09.0 nvme-subsys3 NVM Express Namespaces Device NSID Usage Format Controllers ------------ -------- -------------------------- ---------------- ---------------- nvme1n1 1 134.22 MB / 134.22 MB 512 B + 0 B nvme0, nvme1, nvme2 nvme1n2 2 268.44 MB / 268.44 MB 512 B + 0 B nvme2 nvme3n1 3 268.44 MB / 268.44 MB 512 B + 0 B nvme3 Summary: - Refactored nvme-ns device not to rely on controller during the setup. [1/11 - 5/11] - Introduced a nvme-subsys device model. [6/11] - Create subsystem NQN based on subsystem. [7/11] - Introduced multi-controller model. [8/11 - 9/11] - Updated namespace sharing scheme to be based on nvme-subsys hierarchy. [10/11 - 11/11] Since RFC V1: - Updated namespace sharing scheme to be based on nvme-subsys hierarchy. Thanks, [1] https://lists.gnu.org/archive/html/qemu-block/2021-01/msg00425.html Minwoo Im (11): hw/block/nvme: remove unused argument in nvme_ns_init_zoned hw/block/nvme: open code for volatile write cache hw/block/nvme: remove unused argument in nvme_ns_init_blk hw/block/nvme: split setup and register for namespace hw/block/nvme: remove unused argument in nvme_ns_setup hw/block/nvme: introduce nvme-subsys device hw/block/nvme: support to map controller to a subsystem hw/block/nvme: add CMIC enum value for Identify Controller hw/block/nvme: support for multi-controller in subsystem hw/block/nvme: add NMIC enum value for Identify Namespace hw/block/nvme: support for shared namespace in subsystem hw/block/meson.build | 2 +- hw/block/nvme-ns.c | 40 ++++++++++------ hw/block/nvme-ns.h | 9 +++- hw/block/nvme-subsys.c | 101 +++++++++++++++++++++++++++++++++++++++++ hw/block/nvme-subsys.h | 30 ++++++++++++ hw/block/nvme.c | 92 ++++++++++++++++++++++++++++++++----- hw/block/nvme.h | 5 +- include/block/nvme.h | 8 ++++ 8 files changed, 259 insertions(+), 28 deletions(-) create mode 100644 hw/block/nvme-subsys.c create mode 100644 hw/block/nvme-subsys.h