1 files changed, 182 insertions, 57 deletions

diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c
index c3adefe95e50..f615c3bbb73e 100644
--- a/drivers/target/target_core_user.c
+++ b/drivers/target/target_core_user.c
@@ -28,6 +28,7 @@
 #include <linux/stringify.h>
 #include <linux/bitops.h>
 #include <linux/highmem.h>
+#include <linux/configfs.h>
 #include <net/genetlink.h>
 #include <scsi/scsi_common.h>
 #include <scsi/scsi_proto.h>
@@ -112,6 +113,7 @@ struct tcmu_dev {
 	spinlock_t commands_lock;
 
 	struct timer_list timeout;
+	unsigned int cmd_time_out;
 
 	char dev_config[TCMU_CONFIG_LEN];
 };
@@ -172,7 +174,9 @@ static struct tcmu_cmd *tcmu_alloc_cmd(struct se_cmd *se_cmd)
 
 	tcmu_cmd->se_cmd = se_cmd;
 	tcmu_cmd->tcmu_dev = udev;
-	tcmu_cmd->deadline = jiffies + msecs_to_jiffies(TCMU_TIME_OUT);
+	if (udev->cmd_time_out)
+		tcmu_cmd->deadline = jiffies +
+					msecs_to_jiffies(udev->cmd_time_out);
 
 	idr_preload(GFP_KERNEL);
 	spin_lock_irq(&udev->commands_lock);
@@ -307,24 +311,50 @@ static void free_data_area(struct tcmu_dev *udev, struct tcmu_cmd *cmd)
 		   DATA_BLOCK_BITS);
 }
 
-static void gather_data_area(struct tcmu_dev *udev, unsigned long *cmd_bitmap,
-		struct scatterlist *data_sg, unsigned int data_nents)
+static void gather_data_area(struct tcmu_dev *udev, struct tcmu_cmd *cmd,
+			     bool bidi)
 {
+	struct se_cmd *se_cmd = cmd->se_cmd;
 	int i, block;
 	int block_remaining = 0;
 	void *from, *to;
 	size_t copy_bytes, from_offset;
-	struct scatterlist *sg;
+	struct scatterlist *sg, *data_sg;
+	unsigned int data_nents;
+	DECLARE_BITMAP(bitmap, DATA_BLOCK_BITS);
+
+	bitmap_copy(bitmap, cmd->data_bitmap, DATA_BLOCK_BITS);
+
+	if (!bidi) {
+		data_sg = se_cmd->t_data_sg;
+		data_nents = se_cmd->t_data_nents;
+	} else {
+		uint32_t count;
+
+		/*
+		 * For bidi case, the first count blocks are for Data-Out
+		 * buffer blocks, and before gathering the Data-In buffer
+		 * the Data-Out buffer blocks should be discarded.
+		 */
+		count = DIV_ROUND_UP(se_cmd->data_length, DATA_BLOCK_SIZE);
+		while (count--) {
+			block = find_first_bit(bitmap, DATA_BLOCK_BITS);
+			clear_bit(block, bitmap);
+		}
+
+		data_sg = se_cmd->t_bidi_data_sg;
+		data_nents = se_cmd->t_bidi_data_nents;
+	}
 
 	for_each_sg(data_sg, sg, data_nents, i) {
 		int sg_remaining = sg->length;
 		to = kmap_atomic(sg_page(sg)) + sg->offset;
 		while (sg_remaining > 0) {
 			if (block_remaining == 0) {
-				block = find_first_bit(cmd_bitmap,
+				block = find_first_bit(bitmap,
 						DATA_BLOCK_BITS);
 				block_remaining = DATA_BLOCK_SIZE;
-				clear_bit(block, cmd_bitmap);
+				clear_bit(block, bitmap);
 			}
 			copy_bytes = min_t(size_t, sg_remaining,
 					block_remaining);
@@ -390,6 +420,27 @@ static bool is_ring_space_avail(struct tcmu_dev *udev, size_t cmd_size, size_t d
 	return true;
 }
 
+static inline size_t tcmu_cmd_get_data_length(struct tcmu_cmd *tcmu_cmd)
+{
+	struct se_cmd *se_cmd = tcmu_cmd->se_cmd;
+	size_t data_length = round_up(se_cmd->data_length, DATA_BLOCK_SIZE);
+
+	if (se_cmd->se_cmd_flags & SCF_BIDI) {
+		BUG_ON(!(se_cmd->t_bidi_data_sg && se_cmd->t_bidi_data_nents));
+		data_length += round_up(se_cmd->t_bidi_data_sg->length,
+				DATA_BLOCK_SIZE);
+	}
+
+	return data_length;
+}
+
+static inline uint32_t tcmu_cmd_get_block_cnt(struct tcmu_cmd *tcmu_cmd)
+{
+	size_t data_length = tcmu_cmd_get_data_length(tcmu_cmd);
+
+	return data_length / DATA_BLOCK_SIZE;
+}
+
 static sense_reason_t
 tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd)
 {
@@ -403,7 +454,7 @@ tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd)
 	uint32_t cmd_head;
 	uint64_t cdb_off;
 	bool copy_to_data_area;
-	size_t data_length;
+	size_t data_length = tcmu_cmd_get_data_length(tcmu_cmd);
 	DECLARE_BITMAP(old_bitmap, DATA_BLOCK_BITS);
 
 	if (test_bit(TCMU_DEV_BIT_BROKEN, &udev->flags))
@@ -417,8 +468,7 @@ tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd)
 	 * expensive to tell how many regions are freed in the bitmap
 	*/
 	base_command_size = max(offsetof(struct tcmu_cmd_entry,
-				req.iov[se_cmd->t_bidi_data_nents +
-					se_cmd->t_data_nents]),
+				req.iov[tcmu_cmd_get_block_cnt(tcmu_cmd)]),
 				sizeof(struct tcmu_cmd_entry));
 	command_size = base_command_size
 		+ round_up(scsi_command_size(se_cmd->t_task_cdb), TCMU_OP_ALIGN_SIZE);
@@ -429,11 +479,6 @@ tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd)
 
 	mb = udev->mb_addr;
 	cmd_head = mb->cmd_head % udev->cmdr_size; /* UAM */
-	data_length = se_cmd->data_length;
-	if (se_cmd->se_cmd_flags & SCF_BIDI) {
-		BUG_ON(!(se_cmd->t_bidi_data_sg && se_cmd->t_bidi_data_nents));
-		data_length += se_cmd->t_bidi_data_sg->length;
-	}
 	if ((command_size > (udev->cmdr_size / 2)) ||
 	    data_length > udev->data_size) {
 		pr_warn("TCMU: Request of size %zu/%zu is too big for %u/%zu "
@@ -451,7 +496,11 @@ tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd)
 
 		pr_debug("sleeping for ring space\n");
 		spin_unlock_irq(&udev->cmdr_lock);
-		ret = schedule_timeout(msecs_to_jiffies(TCMU_TIME_OUT));
+		if (udev->cmd_time_out)
+			ret = schedule_timeout(
+					msecs_to_jiffies(udev->cmd_time_out));
+		else
+			ret = schedule_timeout(msecs_to_jiffies(TCMU_TIME_OUT));
 		finish_wait(&udev->wait_cmdr, &__wait);
 		if (!ret) {
 			pr_warn("tcmu: command timed out\n");
@@ -503,11 +552,14 @@ tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd)
 	entry->req.iov_dif_cnt = 0;
 
 	/* Handle BIDI commands */
-	iov_cnt = 0;
-	alloc_and_scatter_data_area(udev, se_cmd->t_bidi_data_sg,
-		se_cmd->t_bidi_data_nents, &iov, &iov_cnt, false);
-	entry->req.iov_bidi_cnt = iov_cnt;
-
+	if (se_cmd->se_cmd_flags & SCF_BIDI) {
+		iov_cnt = 0;
+		iov++;
+		alloc_and_scatter_data_area(udev, se_cmd->t_bidi_data_sg,
+				se_cmd->t_bidi_data_nents, &iov, &iov_cnt,
+				false);
+		entry->req.iov_bidi_cnt = iov_cnt;
+	}
 	/* cmd's data_bitmap is what changed in process */
 	bitmap_xor(tcmu_cmd->data_bitmap, old_bitmap, udev->data_bitmap,
 			DATA_BLOCK_BITS);
@@ -526,8 +578,9 @@ tcmu_queue_cmd_ring(struct tcmu_cmd *tcmu_cmd)
 	/* TODO: only if FLUSH and FUA? */
 	uio_event_notify(&udev->uio_info);
 
-	mod_timer(&udev->timeout,
-		round_jiffies_up(jiffies + msecs_to_jiffies(TCMU_TIME_OUT)));
+	if (udev->cmd_time_out)
+		mod_timer(&udev->timeout, round_jiffies_up(jiffies +
+			  msecs_to_jiffies(udev->cmd_time_out)));
 
 	return TCM_NO_SENSE;
 }
@@ -583,19 +636,11 @@ static void tcmu_handle_completion(struct tcmu_cmd *cmd, struct tcmu_cmd_entry *
 			       se_cmd->scsi_sense_length);
 		free_data_area(udev, cmd);
 	} else if (se_cmd->se_cmd_flags & SCF_BIDI) {
-		DECLARE_BITMAP(bitmap, DATA_BLOCK_BITS);
-
 		/* Get Data-In buffer before clean up */
-		bitmap_copy(bitmap, cmd->data_bitmap, DATA_BLOCK_BITS);
-		gather_data_area(udev, bitmap,
-			se_cmd->t_bidi_data_sg, se_cmd->t_bidi_data_nents);
+		gather_data_area(udev, cmd, true);
 		free_data_area(udev, cmd);
 	} else if (se_cmd->data_direction == DMA_FROM_DEVICE) {
-		DECLARE_BITMAP(bitmap, DATA_BLOCK_BITS);
-
-		bitmap_copy(bitmap, cmd->data_bitmap, DATA_BLOCK_BITS);
-		gather_data_area(udev, bitmap,
-			se_cmd->t_data_sg, se_cmd->t_data_nents);
+		gather_data_area(udev, cmd, false);
 		free_data_area(udev, cmd);
 	} else if (se_cmd->data_direction == DMA_TO_DEVICE) {
 		free_data_area(udev, cmd);
@@ -742,6 +787,7 @@ static struct se_device *tcmu_alloc_device(struct se_hba *hba, const char *name)
 	}
 
 	udev->hba = hba;
+	udev->cmd_time_out = TCMU_TIME_OUT;
 
 	init_waitqueue_head(&udev->wait_cmdr);
 	spin_lock_init(&udev->cmdr_lock);
@@ -960,7 +1006,8 @@ static int tcmu_configure_device(struct se_device *dev)
 	if (dev->dev_attrib.hw_block_size == 0)
 		dev->dev_attrib.hw_block_size = 512;
 	/* Other attributes can be configured in userspace */
-	dev->dev_attrib.hw_max_sectors = 128;
+	if (!dev->dev_attrib.hw_max_sectors)
+		dev->dev_attrib.hw_max_sectors = 128;
 	dev->dev_attrib.hw_queue_depth = 128;
 
 	ret = tcmu_netlink_event(TCMU_CMD_ADDED_DEVICE, udev->uio_info.name,
@@ -997,6 +1044,11 @@ static void tcmu_dev_call_rcu(struct rcu_head *p)
 	kfree(udev);
 }
 
+static bool tcmu_dev_configured(struct tcmu_dev *udev)
+{
+	return udev->uio_info.uio_dev ? true : false;
+}
+
 static void tcmu_free_device(struct se_device *dev)
 {
 	struct tcmu_dev *udev = TCMU_DEV(dev);
@@ -1018,8 +1070,7 @@ static void tcmu_free_device(struct se_device *dev)
 	spin_unlock_irq(&udev->commands_lock);
 	WARN_ON(!all_expired);
 
-	/* Device was configured */
-	if (udev->uio_info.uio_dev) {
+	if (tcmu_dev_configured(udev)) {
 		tcmu_netlink_event(TCMU_CMD_REMOVED_DEVICE, udev->uio_info.name,
 				   udev->uio_info.uio_dev->minor);
 
@@ -1031,16 +1082,42 @@ static void tcmu_free_device(struct se_device *dev)
 }
 
 enum {
-	Opt_dev_config, Opt_dev_size, Opt_hw_block_size, Opt_err,
+	Opt_dev_config, Opt_dev_size, Opt_hw_block_size, Opt_hw_max_sectors,
+	Opt_err,
 };
 
 static match_table_t tokens = {
 	{Opt_dev_config, "dev_config=%s"},
 	{Opt_dev_size, "dev_size=%u"},
 	{Opt_hw_block_size, "hw_block_size=%u"},
+	{Opt_hw_max_sectors, "hw_max_sectors=%u"},
 	{Opt_err, NULL}
 };
 
+static int tcmu_set_dev_attrib(substring_t *arg, u32 *dev_attrib)
+{
+	unsigned long tmp_ul;
+	char *arg_p;
+	int ret;
+
+	arg_p = match_strdup(arg);
+	if (!arg_p)
+		return -ENOMEM;
+
+	ret = kstrtoul(arg_p, 0, &tmp_ul);
+	kfree(arg_p);
+	if (ret < 0) {
+		pr_err("kstrtoul() failed for dev attrib\n");
+		return ret;
+	}
+	if (!tmp_ul) {
+		pr_err("dev attrib must be nonzero\n");
+		return -EINVAL;
+	}
+	*dev_attrib = tmp_ul;
+	return 0;
+}
+
 static ssize_t tcmu_set_configfs_dev_params(struct se_device *dev,
 		const char *page, ssize_t count)
 {
@@ -1048,7 +1125,6 @@ static ssize_t tcmu_set_configfs_dev_params(struct se_device *dev,
 	char *orig, *ptr, *opts, *arg_p;
 	substring_t args[MAX_OPT_ARGS];
 	int ret = 0, token;
-	unsigned long tmp_ul;
 
 	opts = kstrdup(page, GFP_KERNEL);
 	if (!opts)
@@ -1082,26 +1158,19 @@ static ssize_t tcmu_set_configfs_dev_params(struct se_device *dev,
 				pr_err("kstrtoul() failed for dev_size=\n");
 			break;
 		case Opt_hw_block_size:
-			arg_p = match_strdup(&args[0]);
-			if (!arg_p) {
-				ret = -ENOMEM;
-				break;
-			}
-			ret = kstrtoul(arg_p, 0, &tmp_ul);
-			kfree(arg_p);
-			if (ret < 0) {
-				pr_err("kstrtoul() failed for hw_block_size=\n");
-				break;
-			}
-			if (!tmp_ul) {
-				pr_err("hw_block_size must be nonzero\n");
-				break;
-			}
-			dev->dev_attrib.hw_block_size = tmp_ul;
+			ret = tcmu_set_dev_attrib(&args[0],
+					&(dev->dev_attrib.hw_block_size));
+			break;
+		case Opt_hw_max_sectors:
+			ret = tcmu_set_dev_attrib(&args[0],
+					&(dev->dev_attrib.hw_max_sectors));
 			break;
 		default:
 			break;
 		}
+
+		if (ret)
+			break;
 	}
 
 	kfree(orig);
@@ -1134,7 +1203,43 @@ tcmu_parse_cdb(struct se_cmd *cmd)
 	return passthrough_parse_cdb(cmd, tcmu_queue_cmd);
 }
 
-static const struct target_backend_ops tcmu_ops = {
+static ssize_t tcmu_cmd_time_out_show(struct config_item *item, char *page)
+{
+	struct se_dev_attrib *da = container_of(to_config_group(item),
+					struct se_dev_attrib, da_group);
+	struct tcmu_dev *udev = container_of(da->da_dev,
+					struct tcmu_dev, se_dev);
+
+	return snprintf(page, PAGE_SIZE, "%lu\n", udev->cmd_time_out / MSEC_PER_SEC);
+}
+
+static ssize_t tcmu_cmd_time_out_store(struct config_item *item, const char *page,
+				       size_t count)
+{
+	struct se_dev_attrib *da = container_of(to_config_group(item),
+					struct se_dev_attrib, da_group);
+	struct tcmu_dev *udev = container_of(da->da_dev,
+					struct tcmu_dev, se_dev);
+	u32 val;
+	int ret;
+
+	if (da->da_dev->export_count) {
+		pr_err("Unable to set tcmu cmd_time_out while exports exist\n");
+		return -EINVAL;
+	}
+
+	ret = kstrtou32(page, 0, &val);
+	if (ret < 0)
+		return ret;
+
+	udev->cmd_time_out = val * MSEC_PER_SEC;
+	return count;
+}
+CONFIGFS_ATTR(tcmu_, cmd_time_out);
+
+static struct configfs_attribute **tcmu_attrs;
+
+static struct target_backend_ops tcmu_ops = {
 	.name			= "user",
 	.owner			= THIS_MODULE,
 	.transport_flags	= TRANSPORT_FLAG_PASSTHROUGH,
@@ -1148,12 +1253,12 @@ static const struct target_backend_ops tcmu_ops = {
 	.show_configfs_dev_params = tcmu_show_configfs_dev_params,
 	.get_device_type	= sbc_get_device_type,
 	.get_blocks		= tcmu_get_blocks,
-	.tb_dev_attrib_attrs	= passthrough_attrib_attrs,
+	.tb_dev_attrib_attrs	= NULL,
 };
 
 static int __init tcmu_module_init(void)
 {
-	int ret;
+	int ret, i, len = 0;
 
 	BUILD_BUG_ON((sizeof(struct tcmu_cmd_entry) % TCMU_OP_ALIGN_SIZE) != 0);
 
@@ -1175,12 +1280,31 @@ static int __init tcmu_module_init(void)
 		goto out_unreg_device;
 	}
 
+	for (i = 0; passthrough_attrib_attrs[i] != NULL; i++) {
+		len += sizeof(struct configfs_attribute *);
+	}
+	len += sizeof(struct configfs_attribute *) * 2;
+
+	tcmu_attrs = kzalloc(len, GFP_KERNEL);
+	if (!tcmu_attrs) {
+		ret = -ENOMEM;
+		goto out_unreg_genl;
+	}
+
+	for (i = 0; passthrough_attrib_attrs[i] != NULL; i++) {
+		tcmu_attrs[i] = passthrough_attrib_attrs[i];
+	}
+	tcmu_attrs[i] = &tcmu_attr_cmd_time_out;
+	tcmu_ops.tb_dev_attrib_attrs = tcmu_attrs;
+
 	ret = transport_backend_register(&tcmu_ops);
 	if (ret)
-		goto out_unreg_genl;
+		goto out_attrs;
 
 	return 0;
 
+out_attrs:
+	kfree(tcmu_attrs);
 out_unreg_genl:
 	genl_unregister_family(&tcmu_genl_family);
 out_unreg_device:
@@ -1194,6 +1318,7 @@ out_free_cache:
 static void __exit tcmu_module_exit(void)
 {
 	target_backend_unregister(&tcmu_ops);
+	kfree(tcmu_attrs);
 	genl_unregister_family(&tcmu_genl_family);
 	root_device_unregister(tcmu_root_device);
 	kmem_cache_destroy(tcmu_cmd_cache);