[PATCH 2/7] scsi: target: Add atomic se_device fields

[Mike Christie <michael.christie@xxxxxxxxxx>]

This adds atomic fields to the se_device and exports them in configfs.

Initially only target_core_iblock will be supported and we will inherit
all the settings from the block layer except the alignment which userspace
will set.

Signed-off-by: Mike Christie <michael.christie@xxxxxxxxxx>
---
 drivers/target/target_core_configfs.c | 42 +++++++++++++++++++++++++++
 include/target/target_core_base.h     |  6 ++++
 2 files changed, 48 insertions(+)

diff --git a/drivers/target/target_core_configfs.c b/drivers/target/target_core_configfs.c
index c40217f44b1b..f3c7da650f65 100644
--- a/drivers/target/target_core_configfs.c
+++ b/drivers/target/target_core_configfs.c
@@ -578,6 +578,12 @@ DEF_CONFIGFS_ATTRIB_SHOW(unmap_zeroes_data);
 DEF_CONFIGFS_ATTRIB_SHOW(max_write_same_len);
 DEF_CONFIGFS_ATTRIB_SHOW(emulate_rsoc);
 DEF_CONFIGFS_ATTRIB_SHOW(submit_type);
+DEF_CONFIGFS_ATTRIB_SHOW(atomic_supported);
+DEF_CONFIGFS_ATTRIB_SHOW(atomic_alignment);
+DEF_CONFIGFS_ATTRIB_SHOW(atomic_max_len);
+DEF_CONFIGFS_ATTRIB_SHOW(atomic_granularity);
+DEF_CONFIGFS_ATTRIB_SHOW(atomic_max_with_boundary);
+DEF_CONFIGFS_ATTRIB_SHOW(atomic_max_boundary);
 
 #define DEF_CONFIGFS_ATTRIB_STORE_U32(_name)				\
 static ssize_t _name##_store(struct config_item *item, const char *page,\
@@ -1266,6 +1272,30 @@ static ssize_t submit_type_store(struct config_item *item, const char *page,
 	return count;
 }
 
+static ssize_t atomic_alignment_store(struct config_item *item,
+				      const char *page, size_t count)
+{
+	struct se_dev_attrib *da = to_attrib(item);
+	u32 val;
+	int ret;
+
+	ret = kstrtou32(page, 0, &val);
+	if (ret < 0)
+		return ret;
+
+	if (da->da_dev->export_count) {
+		pr_err("dev[%p]: Unable to change SE Device atomic_alignment while export_count is %d\n",
+		       da->da_dev, da->da_dev->export_count);
+		return -EINVAL;
+	}
+
+	da->atomic_alignment = val;
+
+	pr_debug("dev[%p]: SE Device atomic_alignment changed to %u\n",
+		 da->da_dev, val);
+	return count;
+}
+
 CONFIGFS_ATTR(, emulate_model_alias);
 CONFIGFS_ATTR(, emulate_dpo);
 CONFIGFS_ATTR(, emulate_fua_write);
@@ -1302,6 +1332,12 @@ CONFIGFS_ATTR(, max_write_same_len);
 CONFIGFS_ATTR(, alua_support);
 CONFIGFS_ATTR(, pgr_support);
 CONFIGFS_ATTR(, submit_type);
+CONFIGFS_ATTR(, atomic_alignment);
+CONFIGFS_ATTR_RO(, atomic_supported);
+CONFIGFS_ATTR_RO(, atomic_max_len);
+CONFIGFS_ATTR_RO(, atomic_granularity);
+CONFIGFS_ATTR_RO(, atomic_max_with_boundary);
+CONFIGFS_ATTR_RO(, atomic_max_boundary);
 
 /*
  * dev_attrib attributes for devices using the target core SBC/SPC
@@ -1345,6 +1381,12 @@ struct configfs_attribute *sbc_attrib_attrs[] = {
 	&attr_pgr_support,
 	&attr_emulate_rsoc,
 	&attr_submit_type,
+	&attr_atomic_supported,
+	&attr_atomic_alignment,
+	&attr_atomic_max_len,
+	&attr_atomic_granularity,
+	&attr_atomic_max_with_boundary,
+	&attr_atomic_max_boundary,
 	NULL,
 };
 EXPORT_SYMBOL(sbc_attrib_attrs);
diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h
index 97099a5e3f6c..6c87bd018983 100644
--- a/include/target/target_core_base.h
+++ b/include/target/target_core_base.h
@@ -715,6 +715,7 @@ struct se_dev_attrib {
 	bool		is_nonrot;
 	bool		emulate_rest_reord;
 	bool		unmap_zeroes_data;
+	bool		atomic_supported;
 	u32		hw_block_size;
 	u32		block_size;
 	u32		hw_max_sectors;
@@ -726,6 +727,11 @@ struct se_dev_attrib {
 	u32		unmap_granularity;
 	u32		unmap_granularity_alignment;
 	u32		max_write_same_len;
+	u32		atomic_max_len;
+	u32		atomic_alignment;
+	u32		atomic_granularity;
+	u32		atomic_max_with_boundary;
+	u32		atomic_max_boundary;
 	u8		submit_type;
 	struct se_device *da_dev;
 	struct config_group da_group;
-- 
2.34.1