* [PATCH] virtio_pmem: support feature SHMEM_REGION @ 2023-12-19 7:18 Changyuan Lyu 2023-12-20 3:57 ` Jason Wang 0 siblings, 1 reply; 8+ messages in thread From: Changyuan Lyu @ 2023-12-19 7:18 UTC (permalink / raw) To: Pankaj Gupta, Michael S . Tsirkin, Jason Wang Cc: Xuan Zhuo, Dan Williams, Vishal Verma, Dave Jiang, virtualization, nvdimm, linux-kernel, Changyuan Lyu As per virtio spec 1.2 section 5.19.5.2, if the feature VIRTIO_PMEM_F_SHMEM_REGION has been negotiated, the driver MUST query shared memory ID 0 for the physical address ranges. Signed-off-by: Changyuan Lyu <changyuanl@google.com> --- drivers/nvdimm/virtio_pmem.c | 29 +++++++++++++++++++++++++---- include/uapi/linux/virtio_pmem.h | 8 ++++++++ 2 files changed, 33 insertions(+), 4 deletions(-) diff --git a/drivers/nvdimm/virtio_pmem.c b/drivers/nvdimm/virtio_pmem.c index a92eb172f0e7..5b28d543728b 100644 --- a/drivers/nvdimm/virtio_pmem.c +++ b/drivers/nvdimm/virtio_pmem.c @@ -35,6 +35,8 @@ static int virtio_pmem_probe(struct virtio_device *vdev) struct nd_region *nd_region; struct virtio_pmem *vpmem; struct resource res; + struct virtio_shm_region shm_reg; + bool have_shm; int err = 0; if (!vdev->config->get) { @@ -57,10 +59,23 @@ static int virtio_pmem_probe(struct virtio_device *vdev) goto out_err; } - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, - start, &vpmem->start); - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, - size, &vpmem->size); + if (virtio_has_feature(vdev, VIRTIO_PMEM_F_SHMEM_REGION)) { + have_shm = virtio_get_shm_region(vdev, &shm_reg, + (u8)VIRTIO_PMEM_SHMCAP_ID); + if (!have_shm) { + dev_err(&vdev->dev, "failed to get shared memory region %d\n", + VIRTIO_PMEM_SHMCAP_ID); + return -EINVAL; + } + vpmem->start = shm_reg.addr; + vpmem->size = shm_reg.len; + } else { + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, + start, &vpmem->start); + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, + size, &vpmem->size); + } + res.start = vpmem->start; res.end = vpmem->start + vpmem->size - 1; @@ -122,7 +137,13 @@ static void virtio_pmem_remove(struct virtio_device *vdev) virtio_reset_device(vdev); } +static unsigned int features[] = { + VIRTIO_PMEM_F_SHMEM_REGION, +}; + static struct virtio_driver virtio_pmem_driver = { + .feature_table = features, + .feature_table_size = ARRAY_SIZE(features), .driver.name = KBUILD_MODNAME, .driver.owner = THIS_MODULE, .id_table = id_table, diff --git a/include/uapi/linux/virtio_pmem.h b/include/uapi/linux/virtio_pmem.h index d676b3620383..025174f6eacf 100644 --- a/include/uapi/linux/virtio_pmem.h +++ b/include/uapi/linux/virtio_pmem.h @@ -14,6 +14,14 @@ #include <linux/virtio_ids.h> #include <linux/virtio_config.h> +/* Feature bits */ +#define VIRTIO_PMEM_F_SHMEM_REGION 0 /* guest physical address range will be + * indicated as shared memory region 0 + */ + +/* shmid of the shared memory region corresponding to the pmem */ +#define VIRTIO_PMEM_SHMCAP_ID 0 + struct virtio_pmem_config { __le64 start; __le64 size; -- 2.43.0.472.g3155946c3a-goog ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH] virtio_pmem: support feature SHMEM_REGION 2023-12-19 7:18 [PATCH] virtio_pmem: support feature SHMEM_REGION Changyuan Lyu @ 2023-12-20 3:57 ` Jason Wang 2023-12-20 6:13 ` [PATCH v2] " Changyuan Lyu 0 siblings, 1 reply; 8+ messages in thread From: Jason Wang @ 2023-12-20 3:57 UTC (permalink / raw) To: Changyuan Lyu Cc: Pankaj Gupta, Michael S . Tsirkin, Xuan Zhuo, Dan Williams, Vishal Verma, Dave Jiang, virtualization, nvdimm, linux-kernel On Tue, Dec 19, 2023 at 3:19 PM Changyuan Lyu <changyuanl@google.com> wrote: > > As per virtio spec 1.2 section 5.19.5.2, if the feature > VIRTIO_PMEM_F_SHMEM_REGION has been negotiated, the driver MUST query > shared memory ID 0 for the physical address ranges. > > Signed-off-by: Changyuan Lyu <changyuanl@google.com> > --- > drivers/nvdimm/virtio_pmem.c | 29 +++++++++++++++++++++++++---- > include/uapi/linux/virtio_pmem.h | 8 ++++++++ > 2 files changed, 33 insertions(+), 4 deletions(-) > > diff --git a/drivers/nvdimm/virtio_pmem.c b/drivers/nvdimm/virtio_pmem.c > index a92eb172f0e7..5b28d543728b 100644 > --- a/drivers/nvdimm/virtio_pmem.c > +++ b/drivers/nvdimm/virtio_pmem.c > @@ -35,6 +35,8 @@ static int virtio_pmem_probe(struct virtio_device *vdev) > struct nd_region *nd_region; > struct virtio_pmem *vpmem; > struct resource res; > + struct virtio_shm_region shm_reg; > + bool have_shm; > int err = 0; > > if (!vdev->config->get) { > @@ -57,10 +59,23 @@ static int virtio_pmem_probe(struct virtio_device *vdev) > goto out_err; > } > > - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > - start, &vpmem->start); > - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > - size, &vpmem->size); > + if (virtio_has_feature(vdev, VIRTIO_PMEM_F_SHMEM_REGION)) { > + have_shm = virtio_get_shm_region(vdev, &shm_reg, > + (u8)VIRTIO_PMEM_SHMCAP_ID); > + if (!have_shm) { > + dev_err(&vdev->dev, "failed to get shared memory region %d\n", > + VIRTIO_PMEM_SHMCAP_ID); > + return -EINVAL; > + } > + vpmem->start = shm_reg.addr; > + vpmem->size = shm_reg.len; > + } else { > + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > + start, &vpmem->start); > + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > + size, &vpmem->size); > + } > + > > res.start = vpmem->start; > res.end = vpmem->start + vpmem->size - 1; > @@ -122,7 +137,13 @@ static void virtio_pmem_remove(struct virtio_device *vdev) > virtio_reset_device(vdev); > } > > +static unsigned int features[] = { > + VIRTIO_PMEM_F_SHMEM_REGION, > +}; > + > static struct virtio_driver virtio_pmem_driver = { > + .feature_table = features, > + .feature_table_size = ARRAY_SIZE(features), > .driver.name = KBUILD_MODNAME, > .driver.owner = THIS_MODULE, > .id_table = id_table, > diff --git a/include/uapi/linux/virtio_pmem.h b/include/uapi/linux/virtio_pmem.h > index d676b3620383..025174f6eacf 100644 > --- a/include/uapi/linux/virtio_pmem.h > +++ b/include/uapi/linux/virtio_pmem.h > @@ -14,6 +14,14 @@ > #include <linux/virtio_ids.h> > #include <linux/virtio_config.h> > > +/* Feature bits */ > +#define VIRTIO_PMEM_F_SHMEM_REGION 0 /* guest physical address range will be > + * indicated as shared memory region 0 > + */ > + > +/* shmid of the shared memory region corresponding to the pmem */ > +#define VIRTIO_PMEM_SHMCAP_ID 0 NIT: not a native speaker, but any reason for "CAP" here? Would it be better to use SHMMEM_REGION_ID? Thanks > + > struct virtio_pmem_config { > __le64 start; > __le64 size; > -- > 2.43.0.472.g3155946c3a-goog > ^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v2] virtio_pmem: support feature SHMEM_REGION 2023-12-20 3:57 ` Jason Wang @ 2023-12-20 6:13 ` Changyuan Lyu 2023-12-20 7:01 ` Michael S. Tsirkin 0 siblings, 1 reply; 8+ messages in thread From: Changyuan Lyu @ 2023-12-20 6:13 UTC (permalink / raw) To: jasowang Cc: changyuanl, dan.j.williams, dave.jiang, linux-kernel, mst, nvdimm, pankaj.gupta.linux, virtualization, vishal.l.verma, xuanzhuo On Tue, Dec 19, 2023 at 7:57 PM Jason Wang <jasowang@redhat.com> wrote: > > On Tue, Dec 19, 2023 at 3:19 PM Changyuan Lyu <changyuanl@google.com> wrote: > > > > +/* shmid of the shared memory region corresponding to the pmem */ > > +#define VIRTIO_PMEM_SHMCAP_ID 0 > > NIT: not a native speaker, but any reason for "CAP" here? Would it be > better to use SHMMEM_REGION_ID? I was following the name VIRTIO_FS_SHMCAP_ID_CACHE in include/uapi/linux/virtio_fs.h, where I guess "CAP" was referring to the shared memory capability when the device is on PCI bus. I agree SHMMEM_REGION_ID is a better name. On Tue, Dec 19, 2023 at 3:19 PM Changyuan Lyu <changyuanl@google.com> wrote: > > + if (!have_shm) { > + dev_err(&vdev->dev, "failed to get shared memory region %d\n", > + VIRTIO_PMEM_SHMCAP_ID); > + return -EINVAL; > + } I realized that it needs to jump to tag out_vq to clean up vqs instead of simply returnning an error. Thanks for reviewing the patch! ---8<--- As per virtio spec 1.2 section 5.19.5.2, if the feature VIRTIO_PMEM_F_SHMEM_REGION has been negotiated, the driver MUST query shared memory ID 0 for the physical address ranges. Signed-off-by: Changyuan Lyu <changyuanl@google.com> --- V2: * renamed VIRTIO_PMEM_SHMCAP_ID to VIRTIO_PMEM_SHMEM_REGION_ID * fixed the error handling when region 0 does not exist --- drivers/nvdimm/virtio_pmem.c | 30 ++++++++++++++++++++++++++---- include/uapi/linux/virtio_pmem.h | 8 ++++++++ 2 files changed, 34 insertions(+), 4 deletions(-) diff --git a/drivers/nvdimm/virtio_pmem.c b/drivers/nvdimm/virtio_pmem.c index a92eb172f0e7..8e447c7558cb 100644 --- a/drivers/nvdimm/virtio_pmem.c +++ b/drivers/nvdimm/virtio_pmem.c @@ -35,6 +35,8 @@ static int virtio_pmem_probe(struct virtio_device *vdev) struct nd_region *nd_region; struct virtio_pmem *vpmem; struct resource res; + struct virtio_shm_region shm_reg; + bool have_shm; int err = 0; if (!vdev->config->get) { @@ -57,10 +59,24 @@ static int virtio_pmem_probe(struct virtio_device *vdev) goto out_err; } - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, - start, &vpmem->start); - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, - size, &vpmem->size); + if (virtio_has_feature(vdev, VIRTIO_PMEM_F_SHMEM_REGION)) { + have_shm = virtio_get_shm_region(vdev, &shm_reg, + (u8)VIRTIO_PMEM_SHMEM_REGION_ID); + if (!have_shm) { + dev_err(&vdev->dev, "failed to get shared memory region %d\n", + VIRTIO_PMEM_SHMEM_REGION_ID); + err = -ENXIO; + goto out_vq; + } + vpmem->start = shm_reg.addr; + vpmem->size = shm_reg.len; + } else { + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, + start, &vpmem->start); + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, + size, &vpmem->size); + } + res.start = vpmem->start; res.end = vpmem->start + vpmem->size - 1; @@ -122,7 +138,13 @@ static void virtio_pmem_remove(struct virtio_device *vdev) virtio_reset_device(vdev); } +static unsigned int features[] = { + VIRTIO_PMEM_F_SHMEM_REGION, +}; + static struct virtio_driver virtio_pmem_driver = { + .feature_table = features, + .feature_table_size = ARRAY_SIZE(features), .driver.name = KBUILD_MODNAME, .driver.owner = THIS_MODULE, .id_table = id_table, diff --git a/include/uapi/linux/virtio_pmem.h b/include/uapi/linux/virtio_pmem.h index d676b3620383..c5e49b6e58b1 100644 --- a/include/uapi/linux/virtio_pmem.h +++ b/include/uapi/linux/virtio_pmem.h @@ -14,6 +14,14 @@ #include <linux/virtio_ids.h> #include <linux/virtio_config.h> +/* Feature bits */ +#define VIRTIO_PMEM_F_SHMEM_REGION 0 /* guest physical address range will be + * indicated as shared memory region 0 + */ + +/* shmid of the shared memory region corresponding to the pmem */ +#define VIRTIO_PMEM_SHMEM_REGION_ID 0 + struct virtio_pmem_config { __le64 start; __le64 size; -- 2.43.0.472.g3155946c3a-goog ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH v2] virtio_pmem: support feature SHMEM_REGION 2023-12-20 6:13 ` [PATCH v2] " Changyuan Lyu @ 2023-12-20 7:01 ` Michael S. Tsirkin 2023-12-20 7:32 ` [PATCH v3] " Changyuan Lyu 0 siblings, 1 reply; 8+ messages in thread From: Michael S. Tsirkin @ 2023-12-20 7:01 UTC (permalink / raw) To: Changyuan Lyu Cc: jasowang, dan.j.williams, dave.jiang, linux-kernel, nvdimm, pankaj.gupta.linux, virtualization, vishal.l.verma, xuanzhuo On Tue, Dec 19, 2023 at 10:13:00PM -0800, Changyuan Lyu wrote: > On Tue, Dec 19, 2023 at 7:57 PM Jason Wang <jasowang@redhat.com> wrote: > > > > On Tue, Dec 19, 2023 at 3:19 PM Changyuan Lyu <changyuanl@google.com> wrote: > > > > > > +/* shmid of the shared memory region corresponding to the pmem */ > > > +#define VIRTIO_PMEM_SHMCAP_ID 0 > > > > NIT: not a native speaker, but any reason for "CAP" here? Would it be > > better to use SHMMEM_REGION_ID? > > I was following the name VIRTIO_FS_SHMCAP_ID_CACHE in > include/uapi/linux/virtio_fs.h, where I guess "CAP" was referring to > the shared memory capability when the device is on PCI bus. I agree > SHMMEM_REGION_ID is a better name. > > On Tue, Dec 19, 2023 at 3:19 PM Changyuan Lyu <changyuanl@google.com> wrote: > > > > + if (!have_shm) { > > + dev_err(&vdev->dev, "failed to get shared memory region %d\n", > > + VIRTIO_PMEM_SHMCAP_ID); > > + return -EINVAL; > > + } > > I realized that it needs to jump to tag out_vq to clean up vqs > instead of simply returnning an error. > > Thanks for reviewing the patch! > > ---8<--- > > As per virtio spec 1.2 section 5.19.5.2, if the feature > VIRTIO_PMEM_F_SHMEM_REGION has been negotiated, the driver MUST query > shared memory ID 0 for the physical address ranges. This is not a great description. Please describe what the patch does. > Signed-off-by: Changyuan Lyu <changyuanl@google.com> > > --- > V2: > * renamed VIRTIO_PMEM_SHMCAP_ID to VIRTIO_PMEM_SHMEM_REGION_ID > * fixed the error handling when region 0 does not exist > --- > drivers/nvdimm/virtio_pmem.c | 30 ++++++++++++++++++++++++++---- > include/uapi/linux/virtio_pmem.h | 8 ++++++++ > 2 files changed, 34 insertions(+), 4 deletions(-) > > diff --git a/drivers/nvdimm/virtio_pmem.c b/drivers/nvdimm/virtio_pmem.c > index a92eb172f0e7..8e447c7558cb 100644 > --- a/drivers/nvdimm/virtio_pmem.c > +++ b/drivers/nvdimm/virtio_pmem.c > @@ -35,6 +35,8 @@ static int virtio_pmem_probe(struct virtio_device *vdev) > struct nd_region *nd_region; > struct virtio_pmem *vpmem; > struct resource res; > + struct virtio_shm_region shm_reg; > + bool have_shm; > int err = 0; > > if (!vdev->config->get) { > @@ -57,10 +59,24 @@ static int virtio_pmem_probe(struct virtio_device *vdev) > goto out_err; > } > > - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > - start, &vpmem->start); > - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > - size, &vpmem->size); > + if (virtio_has_feature(vdev, VIRTIO_PMEM_F_SHMEM_REGION)) { > + have_shm = virtio_get_shm_region(vdev, &shm_reg, > + (u8)VIRTIO_PMEM_SHMEM_REGION_ID); > + if (!have_shm) { > + dev_err(&vdev->dev, "failed to get shared memory region %d\n", > + VIRTIO_PMEM_SHMEM_REGION_ID); > + err = -ENXIO; > + goto out_vq; > + } > + vpmem->start = shm_reg.addr; > + vpmem->size = shm_reg.len; > + } else { > + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > + start, &vpmem->start); > + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > + size, &vpmem->size); > + } > + > > res.start = vpmem->start; > res.end = vpmem->start + vpmem->size - 1; > @@ -122,7 +138,13 @@ static void virtio_pmem_remove(struct virtio_device *vdev) > virtio_reset_device(vdev); > } > > +static unsigned int features[] = { > + VIRTIO_PMEM_F_SHMEM_REGION, > +}; > + > static struct virtio_driver virtio_pmem_driver = { > + .feature_table = features, > + .feature_table_size = ARRAY_SIZE(features), > .driver.name = KBUILD_MODNAME, > .driver.owner = THIS_MODULE, > .id_table = id_table, > diff --git a/include/uapi/linux/virtio_pmem.h b/include/uapi/linux/virtio_pmem.h > index d676b3620383..c5e49b6e58b1 100644 > --- a/include/uapi/linux/virtio_pmem.h > +++ b/include/uapi/linux/virtio_pmem.h > @@ -14,6 +14,14 @@ > #include <linux/virtio_ids.h> > #include <linux/virtio_config.h> > > +/* Feature bits */ > +#define VIRTIO_PMEM_F_SHMEM_REGION 0 /* guest physical address range will be > + * indicated as shared memory region 0 > + */ > + > +/* shmid of the shared memory region corresponding to the pmem */ > +#define VIRTIO_PMEM_SHMEM_REGION_ID 0 > + > struct virtio_pmem_config { > __le64 start; > __le64 size; > -- > 2.43.0.472.g3155946c3a-goog ^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v3] virtio_pmem: support feature SHMEM_REGION 2023-12-20 7:01 ` Michael S. Tsirkin @ 2023-12-20 7:32 ` Changyuan Lyu 2023-12-20 7:44 ` Michael S. Tsirkin 0 siblings, 1 reply; 8+ messages in thread From: Changyuan Lyu @ 2023-12-20 7:32 UTC (permalink / raw) To: mst Cc: changyuanl, dan.j.williams, dave.jiang, jasowang, linux-kernel, nvdimm, pankaj.gupta.linux, virtualization, vishal.l.verma, xuanzhuo On Tue, Dec 19, 2023 at 11:01 PM Michael S. Tsirkin <mst@redhat.com> wrote: > > This is not a great description. Please describe what the patch does. Thanks for the feedback! Please see the v3 patch below. ---8<--- This patch adds the support for feature VIRTIO_PMEM_F_SHMEM_REGION (virtio spec v1.2 section 5.19.5.2 [1]). Feature bit VIRTIO_PMEM_F_SHMEM_REGION is added to the driver feature table. If the driver feature bit VIRTIO_PMEM_F_SHMEM_REGION is found, during probe, virtio pmem ignores the `start` and `size` fields in device config and looks for a shared memory region of id 0. The physical address range of the pmem is then determined by the physical address range of shared memory region 0. [1] https://docs.oasis-open.org/virtio/virtio/v1.2/csd01/virtio-v1.2-csd01.html#x1-6480002 Signed-off-by: Changyuan Lyu <changyuanl@google.com> --- v3: * updated the patch description. V2: * renamed VIRTIO_PMEM_SHMCAP_ID to VIRTIO_PMEM_SHMEM_REGION_ID * fixed the error handling when region 0 does not exist --- drivers/nvdimm/virtio_pmem.c | 30 ++++++++++++++++++++++++++---- include/uapi/linux/virtio_pmem.h | 8 ++++++++ 2 files changed, 34 insertions(+), 4 deletions(-) diff --git a/drivers/nvdimm/virtio_pmem.c b/drivers/nvdimm/virtio_pmem.c index a92eb172f0e7..8e447c7558cb 100644 --- a/drivers/nvdimm/virtio_pmem.c +++ b/drivers/nvdimm/virtio_pmem.c @@ -35,6 +35,8 @@ static int virtio_pmem_probe(struct virtio_device *vdev) struct nd_region *nd_region; struct virtio_pmem *vpmem; struct resource res; + struct virtio_shm_region shm_reg; + bool have_shm; int err = 0; if (!vdev->config->get) { @@ -57,10 +59,24 @@ static int virtio_pmem_probe(struct virtio_device *vdev) goto out_err; } - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, - start, &vpmem->start); - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, - size, &vpmem->size); + if (virtio_has_feature(vdev, VIRTIO_PMEM_F_SHMEM_REGION)) { + have_shm = virtio_get_shm_region(vdev, &shm_reg, + (u8)VIRTIO_PMEM_SHMEM_REGION_ID); + if (!have_shm) { + dev_err(&vdev->dev, "failed to get shared memory region %d\n", + VIRTIO_PMEM_SHMEM_REGION_ID); + err = -ENXIO; + goto out_vq; + } + vpmem->start = shm_reg.addr; + vpmem->size = shm_reg.len; + } else { + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, + start, &vpmem->start); + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, + size, &vpmem->size); + } + res.start = vpmem->start; res.end = vpmem->start + vpmem->size - 1; @@ -122,7 +138,13 @@ static void virtio_pmem_remove(struct virtio_device *vdev) virtio_reset_device(vdev); } +static unsigned int features[] = { + VIRTIO_PMEM_F_SHMEM_REGION, +}; + static struct virtio_driver virtio_pmem_driver = { + .feature_table = features, + .feature_table_size = ARRAY_SIZE(features), .driver.name = KBUILD_MODNAME, .driver.owner = THIS_MODULE, .id_table = id_table, diff --git a/include/uapi/linux/virtio_pmem.h b/include/uapi/linux/virtio_pmem.h index d676b3620383..c5e49b6e58b1 100644 --- a/include/uapi/linux/virtio_pmem.h +++ b/include/uapi/linux/virtio_pmem.h @@ -14,6 +14,14 @@ #include <linux/virtio_ids.h> #include <linux/virtio_config.h> +/* Feature bits */ +#define VIRTIO_PMEM_F_SHMEM_REGION 0 /* guest physical address range will be + * indicated as shared memory region 0 + */ + +/* shmid of the shared memory region corresponding to the pmem */ +#define VIRTIO_PMEM_SHMEM_REGION_ID 0 + struct virtio_pmem_config { __le64 start; __le64 size; -- 2.43.0.472.g3155946c3a-goog ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH v3] virtio_pmem: support feature SHMEM_REGION 2023-12-20 7:32 ` [PATCH v3] " Changyuan Lyu @ 2023-12-20 7:44 ` Michael S. Tsirkin 2023-12-20 20:49 ` [PATCH v4] " Changyuan Lyu 0 siblings, 1 reply; 8+ messages in thread From: Michael S. Tsirkin @ 2023-12-20 7:44 UTC (permalink / raw) To: Changyuan Lyu Cc: dan.j.williams, dave.jiang, jasowang, linux-kernel, nvdimm, pankaj.gupta.linux, virtualization, vishal.l.verma, xuanzhuo On Tue, Dec 19, 2023 at 11:32:27PM -0800, Changyuan Lyu wrote: > On Tue, Dec 19, 2023 at 11:01 PM Michael S. Tsirkin <mst@redhat.com> wrote: > > > > This is not a great description. Please describe what the patch does. > > Thanks for the feedback! Please see the v3 patch below. > > ---8<--- > > This patch adds the support for feature VIRTIO_PMEM_F_SHMEM_REGION > (virtio spec v1.2 section 5.19.5.2 [1]). Feature bit > VIRTIO_PMEM_F_SHMEM_REGION is added to the driver feature > table. > > If the driver feature bit VIRTIO_PMEM_F_SHMEM_REGION is found, > during probe, virtio pmem ignores the `start` and `size` fields in > device config and looks for a shared memory region of id 0. The > physical address range of the pmem is then determined by the physical > address range of shared memory region 0. > > [1] https://docs.oasis-open.org/virtio/virtio/v1.2/csd01/virtio-v1.2-csd01.html#x1-6480002 > > Signed-off-by: Changyuan Lyu <changyuanl@google.com> > > --- > v3: > * updated the patch description. > V2: > * renamed VIRTIO_PMEM_SHMCAP_ID to VIRTIO_PMEM_SHMEM_REGION_ID > * fixed the error handling when region 0 does not exist > --- > drivers/nvdimm/virtio_pmem.c | 30 ++++++++++++++++++++++++++---- > include/uapi/linux/virtio_pmem.h | 8 ++++++++ > 2 files changed, 34 insertions(+), 4 deletions(-) > > diff --git a/drivers/nvdimm/virtio_pmem.c b/drivers/nvdimm/virtio_pmem.c > index a92eb172f0e7..8e447c7558cb 100644 > --- a/drivers/nvdimm/virtio_pmem.c > +++ b/drivers/nvdimm/virtio_pmem.c > @@ -35,6 +35,8 @@ static int virtio_pmem_probe(struct virtio_device *vdev) > struct nd_region *nd_region; > struct virtio_pmem *vpmem; > struct resource res; > + struct virtio_shm_region shm_reg; > + bool have_shm; > int err = 0; > > if (!vdev->config->get) { > @@ -57,10 +59,24 @@ static int virtio_pmem_probe(struct virtio_device *vdev) > goto out_err; > } > > - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > - start, &vpmem->start); > - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > - size, &vpmem->size); > + if (virtio_has_feature(vdev, VIRTIO_PMEM_F_SHMEM_REGION)) { > + have_shm = virtio_get_shm_region(vdev, &shm_reg, > + (u8)VIRTIO_PMEM_SHMEM_REGION_ID); > + if (!have_shm) { > + dev_err(&vdev->dev, "failed to get shared memory region %d\n", > + VIRTIO_PMEM_SHMEM_REGION_ID); > + err = -ENXIO; > + goto out_vq; Maybe additionally, add a validate callback and clear VIRTIO_PMEM_F_SHMEM_REGION if VIRTIO_PMEM_SHMEM_REGION_ID is not there. > + } > + vpmem->start = shm_reg.addr; > + vpmem->size = shm_reg.len; > + } else { > + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > + start, &vpmem->start); > + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > + size, &vpmem->size); > + } > + > > res.start = vpmem->start; > res.end = vpmem->start + vpmem->size - 1; > @@ -122,7 +138,13 @@ static void virtio_pmem_remove(struct virtio_device *vdev) > virtio_reset_device(vdev); > } > > +static unsigned int features[] = { > + VIRTIO_PMEM_F_SHMEM_REGION, > +}; > + > static struct virtio_driver virtio_pmem_driver = { > + .feature_table = features, > + .feature_table_size = ARRAY_SIZE(features), > .driver.name = KBUILD_MODNAME, > .driver.owner = THIS_MODULE, > .id_table = id_table, > diff --git a/include/uapi/linux/virtio_pmem.h b/include/uapi/linux/virtio_pmem.h > index d676b3620383..c5e49b6e58b1 100644 > --- a/include/uapi/linux/virtio_pmem.h > +++ b/include/uapi/linux/virtio_pmem.h > @@ -14,6 +14,14 @@ > #include <linux/virtio_ids.h> > #include <linux/virtio_config.h> > > +/* Feature bits */ > +#define VIRTIO_PMEM_F_SHMEM_REGION 0 /* guest physical address range will be > + * indicated as shared memory region 0 > + */ Either make this comment shorter to fit in one line, or put the multi-line comment before the define. > + > +/* shmid of the shared memory region corresponding to the pmem */ > +#define VIRTIO_PMEM_SHMEM_REGION_ID 0 > + > struct virtio_pmem_config { > __le64 start; > __le64 size; > -- > 2.43.0.472.g3155946c3a-goog ^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v4] virtio_pmem: support feature SHMEM_REGION 2023-12-20 7:44 ` Michael S. Tsirkin @ 2023-12-20 20:49 ` Changyuan Lyu 2023-12-27 2:51 ` Jason Wang 0 siblings, 1 reply; 8+ messages in thread From: Changyuan Lyu @ 2023-12-20 20:49 UTC (permalink / raw) To: mst Cc: changyuanl, dan.j.williams, dave.jiang, jasowang, linux-kernel, nvdimm, pankaj.gupta.linux, virtualization, vishal.l.verma, xuanzhuo Thanks Michael for the feedback! On Tue, Dec 19, 2023 at 11:44 PM Michael S. Tsirkin <mst@redhat.com> wrote: > > > On Tue, Dec 19, 2023 at 11:32:27PM -0800, Changyuan Lyu wrote: > > > > + if (!have_shm) { > > + dev_err(&vdev->dev, "failed to get shared memory region %d\n", > > + VIRTIO_PMEM_SHMEM_REGION_ID); > > + err = -ENXIO; > > + goto out_vq; > > + } > > Maybe additionally, add a validate callback and clear > VIRTIO_PMEM_F_SHMEM_REGION if VIRTIO_PMEM_SHMEM_REGION_ID is not there. Done. > > +/* Feature bits */ > > +#define VIRTIO_PMEM_F_SHMEM_REGION 0 /* guest physical address range will be > > + * indicated as shared memory region 0 > > + */ > > Either make this comment shorter to fit in one line, or put the > multi-line comment before the define. Done. ---8<--- This patch adds the support for feature VIRTIO_PMEM_F_SHMEM_REGION (virtio spec v1.2 section 5.19.5.2 [1]). During feature negotiation, if VIRTIO_PMEM_F_SHMEM_REGION is offered by the device, the driver looks for a shared memory region of id 0. If it is found, this feature is understood. Otherwise, this feature bit is cleared. During probe, if VIRTIO_PMEM_F_SHMEM_REGION has been negotiated, virtio pmem ignores the `start` and `size` fields in device config and uses the physical address range of shared memory region 0. [1] https://docs.oasis-open.org/virtio/virtio/v1.2/csd01/virtio-v1.2-csd01.html#x1-6480002 Signed-off-by: Changyuan Lyu <changyuanl@google.com> --- v4: * added virtio_pmem_validate callback. v3: * updated the patch description. V2: * renamed VIRTIO_PMEM_SHMCAP_ID to VIRTIO_PMEM_SHMEM_REGION_ID * fixed the error handling when region 0 does not exist --- drivers/nvdimm/virtio_pmem.c | 36 ++++++++++++++++++++++++++++---- include/uapi/linux/virtio_pmem.h | 7 +++++++ 2 files changed, 39 insertions(+), 4 deletions(-) diff --git a/drivers/nvdimm/virtio_pmem.c b/drivers/nvdimm/virtio_pmem.c index a92eb172f0e7..4ceced5cefcf 100644 --- a/drivers/nvdimm/virtio_pmem.c +++ b/drivers/nvdimm/virtio_pmem.c @@ -29,12 +29,27 @@ static int init_vq(struct virtio_pmem *vpmem) return 0; }; +static int virtio_pmem_validate(struct virtio_device *vdev) +{ + struct virtio_shm_region shm_reg; + + if (virtio_has_feature(vdev, VIRTIO_PMEM_F_SHMEM_REGION) && + !virtio_get_shm_region(vdev, &shm_reg, (u8)VIRTIO_PMEM_SHMEM_REGION_ID) + ) { + dev_notice(&vdev->dev, "failed to get shared memory region %d\n", + VIRTIO_PMEM_SHMEM_REGION_ID); + __virtio_clear_bit(vdev, VIRTIO_PMEM_F_SHMEM_REGION); + } + return 0; +} + static int virtio_pmem_probe(struct virtio_device *vdev) { struct nd_region_desc ndr_desc = {}; struct nd_region *nd_region; struct virtio_pmem *vpmem; struct resource res; + struct virtio_shm_region shm_reg; int err = 0; if (!vdev->config->get) { @@ -57,10 +72,16 @@ static int virtio_pmem_probe(struct virtio_device *vdev) goto out_err; } - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, - start, &vpmem->start); - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, - size, &vpmem->size); + if (virtio_has_feature(vdev, VIRTIO_PMEM_F_SHMEM_REGION)) { + virtio_get_shm_region(vdev, &shm_reg, (u8)VIRTIO_PMEM_SHMEM_REGION_ID); + vpmem->start = shm_reg.addr; + vpmem->size = shm_reg.len; + } else { + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, + start, &vpmem->start); + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, + size, &vpmem->size); + } res.start = vpmem->start; res.end = vpmem->start + vpmem->size - 1; @@ -122,10 +143,17 @@ static void virtio_pmem_remove(struct virtio_device *vdev) virtio_reset_device(vdev); } +static unsigned int features[] = { + VIRTIO_PMEM_F_SHMEM_REGION, +}; + static struct virtio_driver virtio_pmem_driver = { + .feature_table = features, + .feature_table_size = ARRAY_SIZE(features), .driver.name = KBUILD_MODNAME, .driver.owner = THIS_MODULE, .id_table = id_table, + .validate = virtio_pmem_validate, .probe = virtio_pmem_probe, .remove = virtio_pmem_remove, }; diff --git a/include/uapi/linux/virtio_pmem.h b/include/uapi/linux/virtio_pmem.h index d676b3620383..ede4f3564977 100644 --- a/include/uapi/linux/virtio_pmem.h +++ b/include/uapi/linux/virtio_pmem.h @@ -14,6 +14,13 @@ #include <linux/virtio_ids.h> #include <linux/virtio_config.h> +/* Feature bits */ +/* guest physical address range will be indicated as shared memory region 0 */ +#define VIRTIO_PMEM_F_SHMEM_REGION 0 + +/* shmid of the shared memory region corresponding to the pmem */ +#define VIRTIO_PMEM_SHMEM_REGION_ID 0 + struct virtio_pmem_config { __le64 start; __le64 size; -- 2.43.0.472.g3155946c3a-goog ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH v4] virtio_pmem: support feature SHMEM_REGION 2023-12-20 20:49 ` [PATCH v4] " Changyuan Lyu @ 2023-12-27 2:51 ` Jason Wang 0 siblings, 0 replies; 8+ messages in thread From: Jason Wang @ 2023-12-27 2:51 UTC (permalink / raw) To: Changyuan Lyu Cc: mst, dan.j.williams, dave.jiang, linux-kernel, nvdimm, pankaj.gupta.linux, virtualization, vishal.l.verma, xuanzhuo On Thu, Dec 21, 2023 at 4:49 AM Changyuan Lyu <changyuanl@google.com> wrote: > > Thanks Michael for the feedback! > > On Tue, Dec 19, 2023 at 11:44 PM Michael S. Tsirkin <mst@redhat.com> wrote: > > > > > On Tue, Dec 19, 2023 at 11:32:27PM -0800, Changyuan Lyu wrote: > > > > > > + if (!have_shm) { > > > + dev_err(&vdev->dev, "failed to get shared memory region %d\n", > > > + VIRTIO_PMEM_SHMEM_REGION_ID); > > > + err = -ENXIO; > > > + goto out_vq; > > > + } > > > > Maybe additionally, add a validate callback and clear > > VIRTIO_PMEM_F_SHMEM_REGION if VIRTIO_PMEM_SHMEM_REGION_ID is not there. > > Done. > > > > +/* Feature bits */ > > > +#define VIRTIO_PMEM_F_SHMEM_REGION 0 /* guest physical address range will be > > > + * indicated as shared memory region 0 > > > + */ > > > > Either make this comment shorter to fit in one line, or put the > > multi-line comment before the define. > > Done. > > ---8<--- > > This patch adds the support for feature VIRTIO_PMEM_F_SHMEM_REGION > (virtio spec v1.2 section 5.19.5.2 [1]). > > During feature negotiation, if VIRTIO_PMEM_F_SHMEM_REGION is offered > by the device, the driver looks for a shared memory region of id 0. > If it is found, this feature is understood. Otherwise, this feature > bit is cleared. > > During probe, if VIRTIO_PMEM_F_SHMEM_REGION has been negotiated, > virtio pmem ignores the `start` and `size` fields in device config > and uses the physical address range of shared memory region 0. > > [1] https://docs.oasis-open.org/virtio/virtio/v1.2/csd01/virtio-v1.2-csd01.html#x1-6480002 > > Signed-off-by: Changyuan Lyu <changyuanl@google.com> Acked-by: Jason Wang <jasowang@redhat.com> Thanks > --- > v4: > * added virtio_pmem_validate callback. > v3: > * updated the patch description. > V2: > * renamed VIRTIO_PMEM_SHMCAP_ID to VIRTIO_PMEM_SHMEM_REGION_ID > * fixed the error handling when region 0 does not exist > --- > drivers/nvdimm/virtio_pmem.c | 36 ++++++++++++++++++++++++++++---- > include/uapi/linux/virtio_pmem.h | 7 +++++++ > 2 files changed, 39 insertions(+), 4 deletions(-) > > diff --git a/drivers/nvdimm/virtio_pmem.c b/drivers/nvdimm/virtio_pmem.c > index a92eb172f0e7..4ceced5cefcf 100644 > --- a/drivers/nvdimm/virtio_pmem.c > +++ b/drivers/nvdimm/virtio_pmem.c > @@ -29,12 +29,27 @@ static int init_vq(struct virtio_pmem *vpmem) > return 0; > }; > > +static int virtio_pmem_validate(struct virtio_device *vdev) > +{ > + struct virtio_shm_region shm_reg; > + > + if (virtio_has_feature(vdev, VIRTIO_PMEM_F_SHMEM_REGION) && > + !virtio_get_shm_region(vdev, &shm_reg, (u8)VIRTIO_PMEM_SHMEM_REGION_ID) > + ) { > + dev_notice(&vdev->dev, "failed to get shared memory region %d\n", > + VIRTIO_PMEM_SHMEM_REGION_ID); > + __virtio_clear_bit(vdev, VIRTIO_PMEM_F_SHMEM_REGION); > + } > + return 0; > +} > + > static int virtio_pmem_probe(struct virtio_device *vdev) > { > struct nd_region_desc ndr_desc = {}; > struct nd_region *nd_region; > struct virtio_pmem *vpmem; > struct resource res; > + struct virtio_shm_region shm_reg; > int err = 0; > > if (!vdev->config->get) { > @@ -57,10 +72,16 @@ static int virtio_pmem_probe(struct virtio_device *vdev) > goto out_err; > } > > - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > - start, &vpmem->start); > - virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > - size, &vpmem->size); > + if (virtio_has_feature(vdev, VIRTIO_PMEM_F_SHMEM_REGION)) { > + virtio_get_shm_region(vdev, &shm_reg, (u8)VIRTIO_PMEM_SHMEM_REGION_ID); > + vpmem->start = shm_reg.addr; > + vpmem->size = shm_reg.len; > + } else { > + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > + start, &vpmem->start); > + virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, > + size, &vpmem->size); > + } > > res.start = vpmem->start; > res.end = vpmem->start + vpmem->size - 1; > @@ -122,10 +143,17 @@ static void virtio_pmem_remove(struct virtio_device *vdev) > virtio_reset_device(vdev); > } > > +static unsigned int features[] = { > + VIRTIO_PMEM_F_SHMEM_REGION, > +}; > + > static struct virtio_driver virtio_pmem_driver = { > + .feature_table = features, > + .feature_table_size = ARRAY_SIZE(features), > .driver.name = KBUILD_MODNAME, > .driver.owner = THIS_MODULE, > .id_table = id_table, > + .validate = virtio_pmem_validate, > .probe = virtio_pmem_probe, > .remove = virtio_pmem_remove, > }; > diff --git a/include/uapi/linux/virtio_pmem.h b/include/uapi/linux/virtio_pmem.h > index d676b3620383..ede4f3564977 100644 > --- a/include/uapi/linux/virtio_pmem.h > +++ b/include/uapi/linux/virtio_pmem.h > @@ -14,6 +14,13 @@ > #include <linux/virtio_ids.h> > #include <linux/virtio_config.h> > > +/* Feature bits */ > +/* guest physical address range will be indicated as shared memory region 0 */ > +#define VIRTIO_PMEM_F_SHMEM_REGION 0 > + > +/* shmid of the shared memory region corresponding to the pmem */ > +#define VIRTIO_PMEM_SHMEM_REGION_ID 0 > + > struct virtio_pmem_config { > __le64 start; > __le64 size; > -- > 2.43.0.472.g3155946c3a-goog > ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2023-12-27 2:51 UTC | newest] Thread overview: 8+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2023-12-19 7:18 [PATCH] virtio_pmem: support feature SHMEM_REGION Changyuan Lyu 2023-12-20 3:57 ` Jason Wang 2023-12-20 6:13 ` [PATCH v2] " Changyuan Lyu 2023-12-20 7:01 ` Michael S. Tsirkin 2023-12-20 7:32 ` [PATCH v3] " Changyuan Lyu 2023-12-20 7:44 ` Michael S. Tsirkin 2023-12-20 20:49 ` [PATCH v4] " Changyuan Lyu 2023-12-27 2:51 ` Jason Wang
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