snic: driver for Cisco SCSI HBA

Cisco has developed a new PCI HBA interface called sNIC, which stands for
SCSI NIC. This is a new storage feature supported on specialized network
adapter. The new PCI function provides a uniform host interface and abstracts
backend storage.

[jejb: fix up checkpatch errors]
Signed-off-by: Narsimhulu Musini <nmusini@cisco.com>
Signed-off-by: Sesidhar Baddela <sebaddel@cisco.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>

1 files changed, 118 insertions, 0 deletions

diff --git a/drivers/scsi/snic/snic_io.h b/drivers/scsi/snic/snic_io.h
new file mode 100644
index 0000000..093d652
--- /dev/null
+++ b/drivers/scsi/snic/snic_io.h
@@ -0,0 +1,118 @@
+/*
+ * Copyright 2014 Cisco Systems, Inc.  All rights reserved.
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef _SNIC_IO_H
+#define _SNIC_IO_H
+
+#define SNIC_DFLT_SG_DESC_CNT	32	/* Default descriptors for sgl */
+#define SNIC_MAX_SG_DESC_CNT	60	/* Max descriptor for sgl */
+#define SNIC_SG_DESC_ALIGN	16	/* Descriptor address alignment */
+
+/* SG descriptor for snic */
+struct snic_sg_desc {
+	__le64 addr;
+	__le32 len;
+	u32 _resvd;
+};
+
+struct snic_dflt_sgl {
+	struct snic_sg_desc sg_desc[SNIC_DFLT_SG_DESC_CNT];
+};
+
+struct snic_max_sgl {
+	struct snic_sg_desc sg_desc[SNIC_MAX_SG_DESC_CNT];
+};
+
+enum snic_req_cache_type {
+	SNIC_REQ_CACHE_DFLT_SGL = 0,	/* cache with default size sgl */
+	SNIC_REQ_CACHE_MAX_SGL,		/* cache with max size sgl */
+	SNIC_REQ_TM_CACHE,		/* cache for task mgmt reqs contains
+					   snic_host_req objects only*/
+	SNIC_REQ_MAX_CACHES		/* number of sgl caches */
+};
+
+/* Per IO internal state */
+struct snic_internal_io_state {
+	char	*rqi;
+	u64	flags;
+	u32	state;
+	u32	abts_status;	/* Abort completion status */
+	u32	lr_status;	/* device reset completion status */
+};
+
+/* IO state machine */
+enum snic_ioreq_state {
+	SNIC_IOREQ_NOT_INITED = 0,
+	SNIC_IOREQ_PENDING,
+	SNIC_IOREQ_ABTS_PENDING,
+	SNIC_IOREQ_ABTS_COMPLETE,
+	SNIC_IOREQ_LR_PENDING,
+	SNIC_IOREQ_LR_COMPLETE,
+	SNIC_IOREQ_COMPLETE,
+};
+
+struct snic;
+struct snic_host_req;
+
+/*
+ * snic_req_info : Contains info about IO, one per scsi command.
+ * Notes: Make sure that the structure is aligned to 16 B
+ * this helps in easy access to snic_req_info from snic_host_req
+ */
+struct snic_req_info {
+	struct list_head list;
+	struct snic_host_req *req;
+	u64	start_time;		/* start time in jiffies */
+	u16	rq_pool_type;		/* noticion of request pool type */
+	u16	req_len;		/* buf len passing to fw (req + sgl)*/
+	u32	tgt_id;
+
+	u32	tm_tag;
+	u8	io_cmpl:1;		/* sets to 1 when fw completes IO */
+	u8	resvd[3];
+	struct scsi_cmnd *sc;		/* Associated scsi cmd */
+	struct snic	*snic;		/* Associated snic */
+	ulong	sge_va;			/* Pointer to Resp Buffer */
+	u64	snsbuf_va;
+
+	struct snic_host_req *abort_req;
+	struct completion *abts_done;
+
+	struct snic_host_req *dr_req;
+	struct completion *dr_done;
+};
+
+
+#define rqi_to_req(rqi)	\
+	((struct snic_host_req *) (((struct snic_req_info *)rqi)->req))
+
+#define req_to_rqi(req)	\
+	((struct snic_req_info *) (((struct snic_host_req *)req)->hdr.init_ctx))
+
+#define req_to_sgl(req)	\
+	((struct snic_sg_desc *) (((struct snic_host_req *)req)+1))
+
+struct snic_req_info *
+snic_req_init(struct snic *, int sg_cnt);
+void snic_req_free(struct snic *, struct snic_req_info *);
+void snic_calc_io_process_time(struct snic *, struct snic_req_info *);
+void snic_pci_unmap_rsp_buf(struct snic *, struct snic_req_info *);
+struct snic_host_req *
+snic_abort_req_init(struct snic *, struct snic_req_info *);
+struct snic_host_req *
+snic_dr_req_init(struct snic *, struct snic_req_info *);
+#endif /* _SNIC_IO_H */