diff options
| author |  Dave Jiang <dave.jiang@intel.com>
| 2023-10-16 10:57:54 -0700 |
|---|---|---|
| committer |  Dan Williams <dan.j.williams@intel.com>
| 2023-10-27 20:29:41 -0700 |
| commit | 05e37b2138a6deb1f23daf1282dc86b29968a1ab (patch) | |
| tree | 190c9abcbf65fe7f5892732154524024e1d059ce | |
| parent | cxl: Add cxl_decoders_committed() helper (diff) | |
| download | linux-05e37b2138a6deb1f23daf1282dc86b29968a1ab.tar.gz linux-05e37b2138a6deb1f23daf1282dc86b29968a1ab.tar.bz2 linux-05e37b2138a6deb1f23daf1282dc86b29968a1ab.zip | |
cxl: Add decoders_committed sysfs attribute to cxl_port
This attribute allows cxl-cli to determine whether there are decoders
committed to a memdev. This is only a snapshot of the state, and
doesn't offer any protection or serialization against a concurrent
disable-region operation.
Reviewed-by: Jim Harris <jim.harris@samsung.com>
Suggested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/169747907439.272156.10261062080830155662.stgit@djiang5-mobl3
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-cxl | 15 | ||||
| -rw-r--r-- | drivers/cxl/core/port.c | 25 |
2 files changed, 40 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-cxl b/Documentation/ABI/testing/sysfs-bus-cxl index 087f762ebfd5..432610f41aee 100644 --- a/Documentation/ABI/testing/sysfs-bus-cxl +++ b/Documentation/ABI/testing/sysfs-bus-cxl @@ -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 diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c index d0ed98a6bade..0adee1e406ec 100644 --- a/drivers/cxl/core/port.c +++ b/drivers/cxl/core/port.c @@ -534,8 +534,33 @@ 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, }; |