| Message ID | 20211007082139.3088615-12-vishal.l.verma@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Initial CXL support | expand |
On Thu, Oct 7, 2021 at 1:22 AM Vishal Verma <vishal.l.verma@intel.com> wrote: > > Add an interface to determine whether a memdev is bound to a region > driver and therefore is currently active. > > For now, this just returns '0' all the time - i.e. devices are always > considered inactive. Flesh this out fully once the region driver is > available. > > Cc: Dan Williams <dan.j.williams@intel.com> > Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> > --- > cxl/lib/libcxl.c | 10 ++++++++++ > cxl/libcxl.h | 1 + > cxl/lib/libcxl.sym | 1 + > 3 files changed, 12 insertions(+) > > diff --git a/cxl/lib/libcxl.c b/cxl/lib/libcxl.c > index de3a8f7..59d091c 100644 > --- a/cxl/lib/libcxl.c > +++ b/cxl/lib/libcxl.c > @@ -362,6 +362,16 @@ CXL_EXPORT size_t cxl_memdev_get_label_size(struct cxl_memdev *memdev) > return memdev->lsa_size; > } > > +CXL_EXPORT int cxl_memdev_is_active(struct cxl_memdev *memdev) > +{ > + /* > + * TODO: Currently memdevs are always considered inactive. Once we have > + * cxl_bus drivers that are bound/unbound to memdevs, we'd use that to > + * determine the active/inactive state. > + */ So I jumped ahead to look at the use case for this and it brings up questions if this is the right check for the label helpers to be using. Note that the LSA commands may still be disabled even if the memdev is inactive. This is because the NVDIMM bridge might be up and have claimed the label operations for exclusive access via /dev/nmemX. So perhaps this should become a narrower focused cxl_memdev_label_area_active() or cxl_memdev_nvdimm_bridge_active(). I think Ben and I still need to arm wrestle how to mediate the label area, but my going-in position is that the CXL subsystem works through the NVDIMM subsystem to coordinate label updates. So cxl_memdev_nvdimm_bridge_active() should be a sufficient check for now. That's determined simply by the existence of a pmemX device as a child of a memX device. > + return 0; > +} > + > CXL_EXPORT void cxl_cmd_unref(struct cxl_cmd *cmd) > { > if (!cmd) > diff --git a/cxl/libcxl.h b/cxl/libcxl.h > index d3b97a1..2e24371 100644 > --- a/cxl/libcxl.h > +++ b/cxl/libcxl.h > @@ -43,6 +43,7 @@ unsigned long long cxl_memdev_get_pmem_size(struct cxl_memdev *memdev); > unsigned long long cxl_memdev_get_ram_size(struct cxl_memdev *memdev); > const char *cxl_memdev_get_firmware_verison(struct cxl_memdev *memdev); > size_t cxl_memdev_get_label_size(struct cxl_memdev *memdev); > +int cxl_memdev_is_active(struct cxl_memdev *memdev); > > #define cxl_memdev_foreach(ctx, memdev) \ > for (memdev = cxl_memdev_get_first(ctx); \ > diff --git a/cxl/lib/libcxl.sym b/cxl/lib/libcxl.sym > index b9feb93..0e82030 100644 > --- a/cxl/lib/libcxl.sym > +++ b/cxl/lib/libcxl.sym > @@ -79,4 +79,5 @@ global: > LIBCXL_4 { > global: > cxl_memdev_get_label_size; > + cxl_memdev_is_active; > } LIBCXL_3; > -- > 2.31.1 >
diff --git a/cxl/lib/libcxl.c b/cxl/lib/libcxl.c index de3a8f7..59d091c 100644 --- a/cxl/lib/libcxl.c +++ b/cxl/lib/libcxl.c @@ -362,6 +362,16 @@ CXL_EXPORT size_t cxl_memdev_get_label_size(struct cxl_memdev *memdev) return memdev->lsa_size; } +CXL_EXPORT int cxl_memdev_is_active(struct cxl_memdev *memdev) +{ + /* + * TODO: Currently memdevs are always considered inactive. Once we have + * cxl_bus drivers that are bound/unbound to memdevs, we'd use that to + * determine the active/inactive state. + */ + return 0; +} + CXL_EXPORT void cxl_cmd_unref(struct cxl_cmd *cmd) { if (!cmd) diff --git a/cxl/libcxl.h b/cxl/libcxl.h index d3b97a1..2e24371 100644 --- a/cxl/libcxl.h +++ b/cxl/libcxl.h @@ -43,6 +43,7 @@ unsigned long long cxl_memdev_get_pmem_size(struct cxl_memdev *memdev); unsigned long long cxl_memdev_get_ram_size(struct cxl_memdev *memdev); const char *cxl_memdev_get_firmware_verison(struct cxl_memdev *memdev); size_t cxl_memdev_get_label_size(struct cxl_memdev *memdev); +int cxl_memdev_is_active(struct cxl_memdev *memdev); #define cxl_memdev_foreach(ctx, memdev) \ for (memdev = cxl_memdev_get_first(ctx); \ diff --git a/cxl/lib/libcxl.sym b/cxl/lib/libcxl.sym index b9feb93..0e82030 100644 --- a/cxl/lib/libcxl.sym +++ b/cxl/lib/libcxl.sym @@ -79,4 +79,5 @@ global: LIBCXL_4 { global: cxl_memdev_get_label_size; + cxl_memdev_is_active; } LIBCXL_3;
Add an interface to determine whether a memdev is bound to a region driver and therefore is currently active. For now, this just returns '0' all the time - i.e. devices are always considered inactive. Flesh this out fully once the region driver is available. Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> --- cxl/lib/libcxl.c | 10 ++++++++++ cxl/libcxl.h | 1 + cxl/lib/libcxl.sym | 1 + 3 files changed, 12 insertions(+)