dmaengine: idxd: Allow ATS disable update only for configurable devices

ATS disable status in a WQ is read-only if the device is not configurable.
This change ensures that the ATS disable attribute can be modified via
sysfs only on configurable devices.

Fixes: 92de5fa2dc39 ("dmaengine: idxd: add ATS disable knob for work queues")
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20230811012635.535413-1-fenghua.yu@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/dma/idxd/sysfs.c b/drivers/dma/idxd/sysfs.c
index d16c164..66c89b0 100644 (file)
--- a/drivers/dma/idxd/sysfs.c
+++ b/drivers/dma/idxd/sysfs.c
@@ -1088,12 +1088,16 @@ static ssize_t wq_ats_disable_store(struct device *dev, struct device_attribute
                                    const char *buf, size_t count)
 {
        struct idxd_wq *wq = confdev_to_wq(dev);
+       struct idxd_device *idxd = wq->idxd;
        bool ats_dis;
        int rc;
 
        if (wq->state != IDXD_WQ_DISABLED)
                return -EPERM;
 
+       if (!test_bit(IDXD_FLAG_CONFIGURABLE, &idxd->flags))
+               return -EPERM;
+
        rc = kstrtobool(buf, &ats_dis);
        if (rc < 0)
                return rc;