Message ID | 20210130002438.1872527-1-ben.widawsky@intel.com (mailing list archive) |
---|---|
Headers | show |
Series | CXL 2.0 Support | expand |
On Fri, Jan 29, 2021 at 4:25 PM Ben Widawsky <ben.widawsky@intel.com> wrote: > > From: Dan Williams <dan.j.williams@intel.com> > > Create the /sys/bus/cxl hierarchy to enumerate: > > * Memory Devices (per-endpoint control devices) > > * Memory Address Space Devices (platform address ranges with > interleaving, performance, and persistence attributes) > > * Memory Regions (active provisioned memory from an address space device > that is in use as System RAM or delegated to libnvdimm as Persistent > Memory regions). > > For now, only the per-endpoint control devices are registered on the > 'cxl' bus. However, going forward it will provide a mechanism to > coordinate cross-device interleave. > > Signed-off-by: Dan Williams <dan.j.williams@intel.com> > Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> > --- > Documentation/ABI/testing/sysfs-bus-cxl | 26 ++ > .../driver-api/cxl/memory-devices.rst | 17 + > drivers/base/core.c | 14 + > drivers/cxl/Makefile | 3 + > drivers/cxl/bus.c | 29 ++ > drivers/cxl/cxl.h | 4 + > drivers/cxl/mem.c | 308 +++++++++++++++++- > include/linux/device.h | 1 + > 8 files changed, 400 insertions(+), 2 deletions(-) > create mode 100644 Documentation/ABI/testing/sysfs-bus-cxl > create mode 100644 drivers/cxl/bus.c [..] > diff --git a/drivers/base/core.c b/drivers/base/core.c > index 25e08e5f40bd..33432a4cbe23 100644 > --- a/drivers/base/core.c > +++ b/drivers/base/core.c > @@ -3179,6 +3179,20 @@ struct device *get_device(struct device *dev) > } > EXPORT_SYMBOL_GPL(get_device); > > +/** > + * get_live_device() - increment reference count for device iff !dead > + * @dev: device. > + * > + * Forward the call to get_device() if the device is still alive. If > + * this is called with the device_lock() held then the device is > + * guaranteed to not die until the device_lock() is dropped. > + */ > +struct device *get_live_device(struct device *dev) > +{ > + return dev && !dev->p->dead ? get_device(dev) : NULL; > +} > +EXPORT_SYMBOL_GPL(get_live_device); Disregard this hunk, it's an abandoned idea that I failed to cleanup.