[PATCH 5/6] scsi tgt: kernel/user interface changes

[FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>]

- merge the tgt command structure with the the event structure for simplicity.
- add a new event type for task management.
- remove some of unused event types.
- send task attributes to user-space daemon.


Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>

---

 drivers/scsi/scsi_tgt_if.c   |   52 ++++++++++++++++++------------------------
 drivers/scsi/scsi_tgt_lib.c  |   10 ++++----
 drivers/scsi/scsi_tgt_priv.h |    4 ++-
 include/scsi/scsi_tgt_if.h   |   50 ++++++++++++++++++++--------------------
 4 files changed, 54 insertions(+), 62 deletions(-)

b38ae32ad97e87f4e4d5fa70b96219cd7e0edabb
diff --git a/drivers/scsi/scsi_tgt_if.c b/drivers/scsi/scsi_tgt_if.c
index 38b35da..a31c8d5 100644
--- a/drivers/scsi/scsi_tgt_if.c
+++ b/drivers/scsi/scsi_tgt_if.c
@@ -35,15 +35,15 @@
 static int tgtd_pid;
 static struct sock *nl_sk;
 
-static int send_event_res(uint16_t type, struct tgt_event *p,
-			  void *data, int dlen, gfp_t flags, pid_t pid)
+static int send_event_rsp(uint16_t type, struct tgt_event *p, gfp_t flags,
+			  pid_t pid)
 {
 	struct tgt_event *ev;
 	struct nlmsghdr *nlh;
 	struct sk_buff *skb;
 	uint32_t len;
 
-	len = NLMSG_SPACE(sizeof(*ev) + dlen);
+	len = NLMSG_SPACE(sizeof(*ev));
 	skb = alloc_skb(len, flags);
 	if (!skb)
 		return -ENOMEM;
@@ -52,8 +52,6 @@ static int send_event_res(uint16_t type,
 
 	ev = NLMSG_DATA(nlh);
 	memcpy(ev, p, sizeof(*ev));
-	if (dlen)
-		memcpy(ev->data, data, dlen);
 
 	return netlink_unicast(nl_sk, skb, pid, 0);
 }
@@ -64,10 +62,12 @@ int scsi_tgt_uspace_send(struct scsi_cmn
 	struct sk_buff *skb;
 	struct nlmsghdr *nlh;
 	struct tgt_event *ev;
-	struct tgt_cmd *tcmd;
 	int err, len;
 
-	len = NLMSG_SPACE(sizeof(*ev) + sizeof(struct tgt_cmd));
+	/* FIXME: we need scsi core to do that. */
+	memcpy(cmd->cmnd, cmd->data_cmnd, MAX_COMMAND_SIZE);
+
+	len = NLMSG_SPACE(sizeof(*ev));
 	/*
 	 * TODO: add MAX_COMMAND_SIZE to ev and add mempool
 	 */
@@ -82,17 +82,13 @@ int scsi_tgt_uspace_send(struct scsi_cmn
 	ev->k.cmd_req.host_no = shost->host_no;
 	ev->k.cmd_req.cid = cmd->request->tag;
 	ev->k.cmd_req.data_len = cmd->request_bufflen;
+	memcpy(ev->k.cmd_req.scb, cmd->cmnd, sizeof(ev->k.cmd_req.scb));
+	memcpy(ev->k.cmd_req.lun, lun, sizeof(ev->k.cmd_req.lun));
+	ev->k.cmd_req.attribute = cmd->tag;
 
 	dprintk("%d %u %u\n", ev->k.cmd_req.host_no, ev->k.cmd_req.cid,
 		ev->k.cmd_req.data_len);
 
-	/* FIXME: we need scsi core to do that. */
-	memcpy(cmd->cmnd, cmd->data_cmnd, MAX_COMMAND_SIZE);
-
-	tcmd = (struct tgt_cmd *) ev->data;
-	memcpy(tcmd->scb, cmd->cmnd, sizeof(tcmd->scb));
-	memcpy(tcmd->lun, lun, sizeof(struct scsi_lun));
-
 	err = netlink_unicast(nl_sk, skb, tgtd_pid, 0);
 	if (err < 0)
 		printk(KERN_ERR "scsi_tgt_uspace_send: could not send skb %d\n",
@@ -104,15 +100,13 @@ int scsi_tgt_uspace_send_status(struct s
 {
 	struct Scsi_Host *shost = scsi_tgt_cmd_to_host(cmd);
 	struct tgt_event ev;
-	char dummy[sizeof(struct tgt_cmd)];
 
 	memset(&ev, 0, sizeof(ev));
 	ev.k.cmd_done.host_no = shost->host_no;
 	ev.k.cmd_done.cid = cmd->request->tag;
 	ev.k.cmd_done.result = cmd->result;
 
-	return send_event_res(TGT_KEVENT_CMD_DONE, &ev, dummy, sizeof(dummy),
-			      gfp_mask, tgtd_pid);
+	return send_event_rsp(TGT_KEVENT_CMD_DONE, &ev, gfp_mask, tgtd_pid);
 }
 
 static int event_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
@@ -124,19 +118,17 @@ static int event_recv_msg(struct sk_buff
 		nlh->nlmsg_pid, current->pid);
 
 	switch (nlh->nlmsg_type) {
-	case TGT_UEVENT_TGTD_BIND:
+	case TGT_UEVENT_REQ:
 		tgtd_pid = NETLINK_CREDS(skb)->pid;
 		break;
-	case TGT_UEVENT_CMD_RES:
+	case TGT_UEVENT_CMD_RSP:
 		/* TODO: handle multiple cmds in one event */
-		err = scsi_tgt_kspace_exec(ev->u.cmd_res.host_no,
-					   ev->u.cmd_res.cid,
-					   ev->u.cmd_res.result,
-					   ev->u.cmd_res.len,
-					   ev->u.cmd_res.offset,
-					   ev->u.cmd_res.uaddr,
-					   ev->u.cmd_res.rw,
-					   ev->u.cmd_res.try_map);
+		err = scsi_tgt_kspace_exec(ev->u.cmd_rsp.host_no,
+					   ev->u.cmd_rsp.cid,
+					   ev->u.cmd_rsp.result,
+					   ev->u.cmd_rsp.len,
+					   ev->u.cmd_rsp.uaddr,
+					   ev->u.cmd_rsp.rw);
 		break;
 	default:
 		eprintk("unknown type %d\n", nlh->nlmsg_type);
@@ -166,12 +158,12 @@ static int event_recv_skb(struct sk_buff
 		 * TODO for passthru commands the lower level should
 		 * probably handle the result or we should modify this
 		 */
-		if (nlh->nlmsg_type != TGT_UEVENT_CMD_RES) {
+		if (nlh->nlmsg_type != TGT_UEVENT_CMD_RSP) {
 			struct tgt_event ev;
 
 			memset(&ev, 0, sizeof(ev));
-			ev.k.event_res.err = err;
-			send_event_res(TGT_KEVENT_RESPONSE, &ev, NULL, 0,
+			ev.k.event_rsp.err = err;
+			send_event_rsp(TGT_KEVENT_RSP, &ev,
 				       GFP_KERNEL | __GFP_NOFAIL,
 					nlh->nlmsg_pid);
 		}
diff --git a/drivers/scsi/scsi_tgt_lib.c b/drivers/scsi/scsi_tgt_lib.c
index 8746236..3549e7c 100644
--- a/drivers/scsi/scsi_tgt_lib.c
+++ b/drivers/scsi/scsi_tgt_lib.c
@@ -315,7 +315,7 @@ static int scsi_map_user_pages(struct sc
 
 	while (len > 0) {
 		dprintk("%lx %u\n", (unsigned long) uaddr, len);
-		bio = bio_map_user(q, NULL, (unsigned long) uaddr, len, rw, 1);
+		bio = bio_map_user(q, NULL, (unsigned long) uaddr, len, rw);
 		if (IS_ERR(bio)) {
 			err = PTR_ERR(bio);
 			dprintk("fail to map %lx %u %d %x\n",
@@ -438,16 +438,16 @@ static int scsi_tgt_copy_sense(struct sc
 	return 0;
 }
 
-int scsi_tgt_kspace_exec(int host_no, u32 cid, int result, u32 len, u64 offset,
-			 unsigned long uaddr, u8 rw, u8 try_map)
+int scsi_tgt_kspace_exec(int host_no, u32 cid, int result, u32 len,
+			 unsigned long uaddr, u8 rw)
 {
 	struct Scsi_Host *shost;
 	struct scsi_cmnd *cmd;
 	struct request *rq;
 	int err = 0;
 
-	dprintk("%d %u %d %u %llu %lx %u %u\n", host_no, cid, result,
-		len, (unsigned long long) offset, uaddr, rw, try_map);
+	dprintk("%d %u %d %u %lx %u\n", host_no, cid, result,
+		len, uaddr, rw);
 
 	/* TODO: replace with a O(1) alg */
 	shost = scsi_host_lookup(host_no);
diff --git a/drivers/scsi/scsi_tgt_priv.h b/drivers/scsi/scsi_tgt_priv.h
index 4236e50..fcf2ec6 100644
--- a/drivers/scsi/scsi_tgt_priv.h
+++ b/drivers/scsi/scsi_tgt_priv.h
@@ -21,5 +21,5 @@ extern int scsi_tgt_if_init(void);
 extern int scsi_tgt_uspace_send(struct scsi_cmnd *cmd, struct scsi_lun *lun, gfp_t flags);
 extern int scsi_tgt_uspace_send_status(struct scsi_cmnd *cmd, gfp_t flags);
 extern int scsi_tgt_kspace_exec(int host_no, u32 cid, int result, u32 len,
-				u64 offset, unsigned long uaddr, u8 rw,
-				u8 try_map);
+				unsigned long uaddr, u8 rw);
+
diff --git a/include/scsi/scsi_tgt_if.h b/include/scsi/scsi_tgt_if.h
index da3a808..ebca452 100644
--- a/include/scsi/scsi_tgt_if.h
+++ b/include/scsi/scsi_tgt_if.h
@@ -24,65 +24,65 @@
 
 enum tgt_event_type {
 	/* user -> kernel */
-	TGT_UEVENT_TGTD_BIND,
-	TGT_UEVENT_TARGET_SETUP,
-	TGT_UEVENT_CMD_RES,
+	TGT_UEVENT_REQ,
+	TGT_UEVENT_CMD_RSP,
+	TGT_UEVENT_TSK_MGMT_RSP,
 
 	/* kernel -> user */
-	TGT_KEVENT_RESPONSE,
+	TGT_KEVENT_RSP,
 	TGT_KEVENT_CMD_REQ,
 	TGT_KEVENT_CMD_DONE,
+	TGT_KEVENT_TSK_MGMT_REQ,
 };
 
 struct tgt_event {
 	/* user-> kernel */
 	union {
 		struct {
-			int pk_fd;
-		} tgtd_bind;
+			int type;
+			int host_no;
+		} event_req;
 		struct {
 			int host_no;
 			uint32_t cid;
 			uint32_t len;
 			int result;
 			uint64_t uaddr;
-			uint64_t offset;
 			uint8_t rw;
-			uint8_t try_map;
-		} cmd_res;
+		} cmd_rsp;
+		struct {
+			int host_no;
+			int mid;
+			int result;
+		} tsk_mgmt_rsp;
 	} u;
 
 	/* kernel -> user */
 	union {
 		struct {
 			int err;
-		} event_res;
+		} event_rsp;
 		struct {
 			int host_no;
 			uint32_t cid;
 			uint32_t data_len;
-			uint64_t dev_id;
+			uint8_t scb[16];
+			uint8_t lun[8];
+			int attribute;
 		} cmd_req;
 		struct {
 			int host_no;
 			uint32_t cid;
 			int result;
 		} cmd_done;
+		struct {
+			int host_no;
+			int mid;
+			uint64_t tag;
+			uint8_t lun[8];
+			int function;
+		} tsk_mgmt_req;
 	} k;
 
-	/*
-	 * I think a pointer is a unsigned long but this struct
-	 * gets passed around from the kernel to userspace and
-	 * back again so to handle some ppc64 setups where userspace is
-	 * 32 bits but the kernel is 64 we do this odd thing
-	 */
-	uint64_t data[0];
-} __attribute__ ((aligned (sizeof(uint64_t))));
-
-struct tgt_cmd {
-	uint8_t scb[16];
-	uint8_t lun[8];
-	int tags;
 } __attribute__ ((aligned (sizeof(uint64_t))));
-
 #endif
-- 
1.1.5