[PATCHv5 2/5] scsi: Export blacklist flags to sysfs

[Hannes Reinecke <hare@suse.de>]

Each scsi device is scanned according to the found blacklist flags,
but this information is never presented to sysfs.
This makes it quite hard to figure out if blacklisting worked as
expected.
With this patch we're exporting an additional attribute 'blacklist'
containing the blacklist flags for this device.

Signed-off-by: Hannes Reinecke <hare@suse.com>
---
 drivers/scsi/Makefile     |  8 ++++++++
 drivers/scsi/scsi_scan.c  |  1 +
 drivers/scsi/scsi_sysfs.c | 40 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 49 insertions(+)

diff --git a/drivers/scsi/Makefile b/drivers/scsi/Makefile
index 93dbe58c47c8..c4298c7fe819 100644
--- a/drivers/scsi/Makefile
+++ b/drivers/scsi/Makefile
@@ -191,6 +191,14 @@ clean-files :=	53c700_d.h 53c700_u.h
 
 $(obj)/53c700.o $(MODVERDIR)/$(obj)/53c700.ver: $(obj)/53c700_d.h
 
+$(obj)/scsi_sysfs.o: $(obj)/scsi_devinfo_tbl.c
+
+quiet_cmd_bflags = GEN     $@
+	cmd_bflags = sed -n 's/.*BLIST_\([A-Z0-9_]*\) *.*/BLIST_FLAG_NAME(\1),/p' $< > $@
+
+$(obj)/scsi_devinfo_tbl.c: include/scsi/scsi_devinfo.h
+	$(call if_changed,bflags)
+
 # If you want to play with the firmware, uncomment
 # GENERATE_FIRMWARE := 1
 
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index e7818afeda2b..26edd61a5554 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -984,6 +984,7 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
 		scsi_attach_vpd(sdev);
 
 	sdev->max_queue_depth = sdev->queue_depth;
+	sdev->sdev_bflags = *bflags;
 
 	/*
 	 * Ok, the device is now all set up, we can
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index cfc5e316f6cb..e57448acfdd3 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -20,6 +20,7 @@
 #include <scsi/scsi_dh.h>
 #include <scsi/scsi_transport.h>
 #include <scsi/scsi_driver.h>
+#include <scsi/scsi_devinfo.h>
 
 #include "scsi_priv.h"
 #include "scsi_logging.h"
@@ -966,6 +967,44 @@ sdev_show_wwid(struct device *dev, struct device_attribute *attr,
 }
 static DEVICE_ATTR(wwid, S_IRUGO, sdev_show_wwid, NULL);
 
+#define BLIST_FLAG_NAME(name) [ilog2(BLIST_##name)] = #name
+static const char *const sdev_bflags_name[] = {
+#include "scsi_devinfo_tbl.c"
+};
+#undef BLIST_FLAG_NAME
+
+static ssize_t
+sdev_show_blacklist(struct device *dev, struct device_attribute *attr,
+		    char *buf)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	int i;
+	ssize_t len = 0;
+
+	for (i = 0; i < sizeof(sdev->sdev_bflags) * BITS_PER_BYTE; i++) {
+		const char *name = NULL;
+
+		if (!(sdev->sdev_bflags & BIT(i)))
+			continue;
+		if (i < ARRAY_SIZE(sdev_bflags_name) && sdev_bflags_name[i])
+			name = sdev_bflags_name[i];
+
+		if (len)
+			len += snprintf(buf + len, 2, " ");
+
+		if (name)
+			len += snprintf(buf + len, strlen(name) + 1,
+					"%s", name);
+		else
+			len += snprintf(buf + len, 67,
+					"INVALID_BIT(%d)", i);
+	}
+	if (len)
+		len += snprintf(buf + len, 2, "\n");
+	return len;
+}
+static DEVICE_ATTR(blacklist, S_IRUGO, sdev_show_blacklist, NULL);
+
 #ifdef CONFIG_SCSI_DH
 static ssize_t
 sdev_show_dh_state(struct device *dev, struct device_attribute *attr,
@@ -1151,6 +1190,7 @@ static struct attribute *scsi_sdev_attrs[] = {
 	&dev_attr_queue_depth.attr,
 	&dev_attr_queue_type.attr,
 	&dev_attr_wwid.attr,
+	&dev_attr_blacklist.attr,
 #ifdef CONFIG_SCSI_DH
 	&dev_attr_dh_state.attr,
 	&dev_attr_access_state.attr,
-- 
2.12.3