nvme: expose active quirks in sysfs

Currently, there is no straightforward way for a user to inspect
which quirks are active for a given device from userspace.

Add a new "quirks" sysfs attribute to the nvme controller device.

Reading this file will display a human-readable list
of all active quirks, with each quirk name on a new line.
If no quirks are active, it will display "none".

Tested-by: John Meneghini <jmeneghi@redhat.com>
Reviewed-by: John Meneghini <jmeneghi@redhat.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>

diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index 9a5f28c5103c5c42777bd9309a983ef0196c1b95..523015ae2add7a6a9369fc5cd9fa6126575afded 100644 (file)
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -180,6 +180,60 @@ enum nvme_quirks {
        NVME_QUIRK_DMAPOOL_ALIGN_512            = (1 << 22),
 };
 
+static inline char *nvme_quirk_name(enum nvme_quirks q)
+{
+       switch (q) {
+       case NVME_QUIRK_STRIPE_SIZE:
+               return "stripe_size";
+       case NVME_QUIRK_IDENTIFY_CNS:
+               return "identify_cns";
+       case NVME_QUIRK_DEALLOCATE_ZEROES:
+               return "deallocate_zeroes";
+       case NVME_QUIRK_DELAY_BEFORE_CHK_RDY:
+               return "delay_before_chk_rdy";
+       case NVME_QUIRK_NO_APST:
+               return "no_apst";
+       case NVME_QUIRK_NO_DEEPEST_PS:
+               return "no_deepest_ps";
+       case NVME_QUIRK_QDEPTH_ONE:
+               return "qdepth_one";
+       case NVME_QUIRK_MEDIUM_PRIO_SQ:
+               return "medium_prio_sq";
+       case NVME_QUIRK_IGNORE_DEV_SUBNQN:
+               return "ignore_dev_subnqn";
+       case NVME_QUIRK_DISABLE_WRITE_ZEROES:
+               return "disable_write_zeroes";
+       case NVME_QUIRK_SIMPLE_SUSPEND:
+               return "simple_suspend";
+       case NVME_QUIRK_SINGLE_VECTOR:
+               return "single_vector";
+       case NVME_QUIRK_128_BYTES_SQES:
+               return "128_bytes_sqes";
+       case NVME_QUIRK_SHARED_TAGS:
+               return "shared_tags";
+       case NVME_QUIRK_NO_TEMP_THRESH_CHANGE:
+               return "no_temp_thresh_change";
+       case NVME_QUIRK_NO_NS_DESC_LIST:
+               return "no_ns_desc_list";
+       case NVME_QUIRK_DMA_ADDRESS_BITS_48:
+               return "dma_address_bits_48";
+       case NVME_QUIRK_SKIP_CID_GEN:
+               return "skip_cid_gen";
+       case NVME_QUIRK_BOGUS_NID:
+               return "bogus_nid";
+       case NVME_QUIRK_NO_SECONDARY_TEMP_THRESH:
+               return "no_secondary_temp_thresh";
+       case NVME_QUIRK_FORCE_NO_SIMPLE_SUSPEND:
+               return "force_no_simple_suspend";
+       case NVME_QUIRK_BROKEN_MSI:
+               return "broken_msi";
+       case NVME_QUIRK_DMAPOOL_ALIGN_512:
+               return "dmapool_align_512";
+       }
+
+       return "unknown";
+}
+
 /*
  * Common request structure for NVMe passthrough.  All drivers must have
  * this structure as the first member of their request-private data.

diff --git a/drivers/nvme/host/sysfs.c b/drivers/nvme/host/sysfs.c
index 29430949ce2f0a28e2f7c4b61098dc7decd7eea7..16c6fea4b2db6306a6982aec8598f8a450941d4e 100644 (file)
--- a/drivers/nvme/host/sysfs.c
+++ b/drivers/nvme/host/sysfs.c
@@ -601,6 +601,28 @@ static ssize_t dctype_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(dctype);
 
+static ssize_t quirks_show(struct device *dev, struct device_attribute *attr,
+                char *buf)
+{
+       int count = 0, i;
+       struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
+       unsigned long quirks = ctrl->quirks;
+
+       if (!quirks)
+               return sysfs_emit(buf, "none\n");
+
+       for (i = 0; quirks; ++i) {
+               if (quirks & 1) {
+                       count += sysfs_emit_at(buf, count, "%s\n",
+                                       nvme_quirk_name(BIT(i)));
+               }
+               quirks >>= 1;
+       }
+
+       return count;
+}
+static DEVICE_ATTR_RO(quirks);
+
 #ifdef CONFIG_NVME_HOST_AUTH
 static ssize_t nvme_ctrl_dhchap_secret_show(struct device *dev,
                struct device_attribute *attr, char *buf)
@@ -742,6 +764,7 @@ static struct attribute *nvme_dev_attrs[] = {
        &dev_attr_kato.attr,
        &dev_attr_cntrltype.attr,
        &dev_attr_dctype.attr,
+       &dev_attr_quirks.attr,
 #ifdef CONFIG_NVME_HOST_AUTH
        &dev_attr_dhchap_secret.attr,
        &dev_attr_dhchap_ctrl_secret.attr,