| Message ID | 20231220204906.566922-1-changyuanl@google.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 35967bdcff325f4572b21b0d0005318da7e03f53 |
| Delegated to: | Ira Weiny |
| Headers | show |
| Series | [v4] virtio_pmem: support feature SHMEM_REGION | expand |
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 >
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;