Commit b3cfdbf6 authored by Dan Williams's avatar Dan Williams
Browse files

Merge branch 'for-6.7/cxl-commited' into cxl/next 

Add the committed decoder sysfs attribute for v6.7.
parents de5512b2 05e37b21

Documentation/ABI/testing/sysfs-bus-cxl

+15 −0
Original line number Diff line number Diff line
@@ -178,6 +178,21 @@ Description: 
		hardware decoder target list.





What:		/sys/bus/cxl/devices/portX/decoders_committed

Date:		October, 2023

KernelVersion:	v6.7

Contact:	linux-cxl@vger.kernel.org

Description:

		(RO) A memory device is considered active when any of its

		decoders are in the "committed" state (See CXL 3.0 8.2.4.19.7

		CXL HDM Decoder n Control Register). Hotplug and destructive

		operations like "sanitize" are blocked while device is actively

		decoding a Host Physical Address range. Note that this number

		may be elevated without any regionX objects active or even

		enumerated, as this may be due to decoders established by

		platform firwmare or a previous kernel (kexec).





What:		/sys/bus/cxl/devices/decoderX.Y

Date:		June, 2021

KernelVersion:	v5.14

drivers/cxl/core/hdm.c

+4 −3
Original line number Diff line number Diff line
@@ -633,10 +633,11 @@ static int cxl_decoder_commit(struct cxl_decoder *cxld) 
	if (cxld->flags & CXL_DECODER_F_ENABLE)

		return 0;



	if (port->commit_end + 1 != id) {

	if (cxl_num_decoders_committed(port) != id) {

		dev_dbg(&port->dev,

			"%s: out of order commit, expected decoder%d.%d\n",

			dev_name(&cxld->dev), port->id, port->commit_end + 1);

			dev_name(&cxld->dev), port->id,

			cxl_num_decoders_committed(port));

		return -EBUSY;

	}
@@ -853,7 +854,7 @@ static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld, 
			cxld->target_type = CXL_DECODER_HOSTONLYMEM;

		else

			cxld->target_type = CXL_DECODER_DEVMEM;

		if (cxld->id != port->commit_end + 1) {

		if (cxld->id != cxl_num_decoders_committed(port)) {

			dev_warn(&port->dev,

				 "decoder%d.%d: Committed out of order\n",

				 port->id, cxld->id);

drivers/cxl/core/mbox.c

+1 −1
Original line number Diff line number Diff line
@@ -1200,7 +1200,7 @@ int cxl_mem_sanitize(struct cxl_memdev *cxlmd, u16 cmd) 
	 * Require an endpoint to be safe otherwise the driver can not

	 * be sure that the device is unmapped.

	 */

	if (endpoint && endpoint->commit_end == -1)

	if (endpoint && cxl_num_decoders_committed(endpoint) == 0)

		rc = __cxl_mem_sanitize(mds, cmd);

	else

		rc = -EBUSY;

drivers/cxl/core/memdev.c

+2 −2
Original line number Diff line number Diff line
@@ -231,7 +231,7 @@ int cxl_trigger_poison_list(struct cxl_memdev *cxlmd) 
	if (rc)

		return rc;



	if (port->commit_end == -1) {

	if (cxl_num_decoders_committed(port) == 0) {

		/* No regions mapped to this memdev */

		rc = cxl_get_poison_by_memdev(cxlmd);

	} else {
@@ -282,7 +282,7 @@ static struct cxl_region *cxl_dpa_to_region(struct cxl_memdev *cxlmd, u64 dpa) 
		.dpa = dpa,

	};

	port = cxlmd->endpoint;

	if (port && is_cxl_endpoint(port) && port->commit_end != -1)

	if (port && is_cxl_endpoint(port) && cxl_num_decoders_committed(port))

		device_for_each_child(&port->dev, &ctx, __cxl_dpa_to_region);



	return ctx.cxlr;

drivers/cxl/core/port.c

+32 −0
Original line number Diff line number Diff line
@@ -37,6 +37,13 @@ DECLARE_RWSEM(cxl_region_rwsem); 
static DEFINE_IDA(cxl_port_ida);

static DEFINE_XARRAY(cxl_root_buses);



int cxl_num_decoders_committed(struct cxl_port *port)

{

	lockdep_assert_held(&cxl_region_rwsem);



	return port->commit_end + 1;

}



static ssize_t devtype_show(struct device *dev, struct device_attribute *attr,

			    char *buf)

{
@@ -537,8 +544,33 @@ static void cxl_port_release(struct device *dev) 
	kfree(port);

}



static ssize_t decoders_committed_show(struct device *dev,

				       struct device_attribute *attr, char *buf)

{

	struct cxl_port *port = to_cxl_port(dev);

	int rc;



	down_read(&cxl_region_rwsem);

	rc = sysfs_emit(buf, "%d\n", cxl_num_decoders_committed(port));

	up_read(&cxl_region_rwsem);



	return rc;

}



static DEVICE_ATTR_RO(decoders_committed);



static struct attribute *cxl_port_attrs[] = {

	&dev_attr_decoders_committed.attr,

	NULL,

};



static struct attribute_group cxl_port_attribute_group = {

	.attrs = cxl_port_attrs,

};



static const struct attribute_group *cxl_port_attribute_groups[] = {

	&cxl_base_attribute_group,

	&cxl_port_attribute_group,

	NULL,

};