ibmvscsis: Initial commit of IBM VSCSI Tgt Driver

This driver is a pick up of the old IBM VIO scsi Target Driver
that was started by Nick and Fujita 2-4 years ago.
http://comments.gmane.org/gmane.linux.scsi/90119

The driver provides a virtual SCSI device on IBM Power Servers.

This patch contains the fifth version for an initial merge of the
tcm ibmvscsis driver. More information on this driver and config
can be found:

https://github.com/powervm/ibmvscsis/wiki/Configuration
http://www.linux-iscsi.org/wiki/IBM_vSCSI

(Drop extra libsrp review breakage + Fix kconfig typo - nab)

Signed-off-by: Steven Royer <seroyer@linux.vnet.ibm.com>
Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
Signed-off-by: Michael Cyr <mikecyr@linux.vnet.ibm.com>
Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Cc: FUJITA Tomonori <tomof@acm.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 files changed, 123 insertions, 0 deletions

diff --git a/drivers/scsi/ibmvscsi_tgt/libsrp.h b/drivers/scsi/ibmvscsi_tgt/libsrp.h
new file mode 100644
index 000000000000..4696f331453e
--- /dev/null
+++ b/drivers/scsi/ibmvscsi_tgt/libsrp.h
@@ -0,0 +1,123 @@
+#ifndef __LIBSRP_H__
+#define __LIBSRP_H__
+
+#include <linux/list.h>
+#include <linux/kfifo.h>
+#include <scsi/srp.h>
+
+enum srp_valid {
+	INVALIDATE_CMD_RESP_EL = 0,
+	VALID_CMD_RESP_EL = 0x80,
+	VALID_INIT_MSG = 0xC0,
+	VALID_TRANS_EVENT = 0xFF
+};
+
+enum srp_format {
+	SRP_FORMAT = 1,
+	MAD_FORMAT = 2,
+	OS400_FORMAT = 3,
+	AIX_FORMAT = 4,
+	LINUX_FORMAT = 5,
+	MESSAGE_IN_CRQ = 6
+};
+
+enum srp_init_msg {
+	INIT_MSG = 1,
+	INIT_COMPLETE_MSG = 2
+};
+
+enum srp_trans_event {
+	UNUSED_FORMAT = 0,
+	PARTNER_FAILED = 1,
+	PARTNER_DEREGISTER = 2,
+	MIGRATED = 6
+};
+
+enum srp_status {
+	HEADER_DESCRIPTOR = 0xF1,
+	PING = 0xF5,
+	PING_RESPONSE = 0xF6
+};
+
+enum srp_mad_version {
+	MAD_VERSION_1 = 1
+};
+
+enum srp_os_type {
+	OS400 = 1,
+	LINUX = 2,
+	AIX = 3,
+	OFW = 4
+};
+
+enum srp_task_attributes {
+	SRP_SIMPLE_TASK = 0,
+	SRP_HEAD_TASK = 1,
+	SRP_ORDERED_TASK = 2,
+	SRP_ACA_TASK = 4
+};
+
+enum {
+	SRP_TASK_MANAGEMENT_FUNCTION_COMPLETE           = 0,
+	SRP_REQUEST_FIELDS_INVALID                      = 2,
+	SRP_TASK_MANAGEMENT_FUNCTION_NOT_SUPPORTED      = 4,
+	SRP_TASK_MANAGEMENT_FUNCTION_FAILED             = 5
+};
+
+struct srp_buf {
+	dma_addr_t dma;
+	void *buf;
+};
+
+struct srp_queue {
+	void *pool;
+	void *items;
+	struct kfifo queue;
+	spinlock_t lock;
+};
+
+struct srp_target {
+	struct device *dev;
+
+	spinlock_t lock;
+	struct list_head cmd_queue;
+
+	size_t srp_iu_size;
+	struct srp_queue iu_queue;
+	size_t rx_ring_size;
+	struct srp_buf **rx_ring;
+
+	void *ldata;
+};
+
+struct iu_entry {
+	struct srp_target *target;
+
+	struct list_head ilist;
+	dma_addr_t remote_token;
+	unsigned long flags;
+
+	struct srp_buf *sbuf;
+	u16 iu_len;
+};
+
+struct ibmvscsis_cmd;
+
+typedef int (srp_rdma_t)(struct ibmvscsis_cmd *, struct scatterlist *, int,
+			 struct srp_direct_buf *, int,
+			 enum dma_data_direction, unsigned int);
+int srp_target_alloc(struct srp_target *, struct device *, size_t, size_t);
+void srp_target_free(struct srp_target *);
+struct iu_entry *srp_iu_get(struct srp_target *);
+void srp_iu_put(struct iu_entry *);
+int srp_transfer_data(struct ibmvscsis_cmd *, struct srp_cmd *,
+		      srp_rdma_t, int, int);
+u64 srp_data_length(struct srp_cmd *cmd, enum dma_data_direction dir);
+int srp_get_desc_table(struct srp_cmd *srp_cmd, enum dma_data_direction *dir,
+		       u64 *data_len);
+static inline int srp_cmd_direction(struct srp_cmd *cmd)
+{
+	return (cmd->buf_fmt >> 4) ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
+}
+
+#endif