This patch enables allocation of request and response information units on the
send queue instead of only requests, and implements processing of SRP_CRED_REQ
information units. Also, declarations have been added to include/scsi/srp.h
for the SRP_CRED_REQ and SRP_CRED_RSP information units.
Signed-off-by: Bart Van Assche <bart.vanass...@gmail.com>
Cc: Roland Dreier <rola...@cisco.com>
Cc: David Dillow <d...@thedillows.org>
---
drivers/infiniband/ulp/srp/ib_srp.c | 151 +++++++++++++++++++++++++++++++----
drivers/infiniband/ulp/srp/ib_srp.h | 7 ++
include/scsi/srp.h | 19 +++++
3 files changed, 162 insertions(+), 15 deletions(-)
diff --git a/drivers/infiniband/ulp/srp/ib_srp.c
b/drivers/infiniband/ulp/srp/ib_srp.c
index 8252a45..c810e52 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -93,6 +93,9 @@ static void srp_notify_recv_thread(struct ib_cq *cq, void
*target_ptr);
static int srp_compl_thread(void *target_ptr);
static void srp_send_completion(struct ib_cq *cq, void *target_ptr);
static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event);
+static struct srp_iu *__srp_get_tx_rsp_iu(struct srp_target_port *target);
+static int __srp_post_send_rsp(struct srp_target_port *target,
+ struct srp_iu *iu, int len);
static struct scsi_transport_template *ib_srp_transport_template;
@@ -628,6 +631,8 @@ static int srp_reconnect_target(struct srp_target_port
*target)
target->rx_head = 0;
target->tx_head = 0;
target->tx_tail = 0;
+ target->tx_req = 0;
+ target->tx_rsp = 0;
target->qp_in_error = 0;
ret = srp_connect_target(target);
@@ -933,6 +938,69 @@ static void srp_process_rsp(struct srp_target_port
*target, struct srp_rsp *rsp)
spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
}
+/*
+ * Must be called with target->scsi_host->host_lock locked to protect
+ * target->req_lim.
+ */
+static int srp_handle_cred_req(struct srp_target_port *target,
+ struct srp_cred_req *req,
+ struct srp_cred_rsp *rsp)
+{
+ target->req_lim += be32_to_cpu(req->req_lim_delta);
+
+ memset(rsp, 0, sizeof *rsp);
+ rsp->opcode = SRP_CRED_RSP;
+ rsp->tag = req->tag;
+
+ return 0;
+}
+
+static void srp_handle_req(struct srp_target_port *target,
+ struct srp_iu *req_iu)
+{
+ struct ib_device *dev;
+ u8 *req_buf;
+ unsigned long flags;
+ struct srp_iu *rsp_iu;
+ u8 *rsp_buf;
+ int res;
+
+ dev = target->srp_host->srp_dev->dev;
+ req_buf = req_iu->buf;
+
+ spin_lock_irqsave(target->scsi_host->host_lock, flags);
+
+ rsp_iu = __srp_get_tx_rsp_iu(target);
+ if (!rsp_iu)
+ goto out_unlock;
+
+ rsp_buf = rsp_iu->buf;
+
+ res = -EINVAL;
+
+ switch (req_buf[0]) {
+ case SRP_CRED_REQ:
+ res = srp_handle_cred_req(target,
+ (struct srp_cred_req *)req_buf,
+ (struct srp_cred_rsp *)rsp_buf);
+ break;
+ }
+
+ if (res == 0) {
+ ib_dma_sync_single_for_device(dev, rsp_iu->dma, srp_max_iu_len,
+ DMA_TO_DEVICE);
+
+ res = __srp_post_send_rsp(target, rsp_iu, sizeof *rsp_iu);
+ if (res)
+ shost_printk(KERN_ERR, target->scsi_host,
+ PFX "Sending response failed -- res = %d\n",
+ res);
+ }
+
+out_unlock:
+ spin_unlock_irqrestore(target->scsi_host->host_lock, flags);
+}
+
static void srp_handle_recv(struct srp_target_port *target, struct ib_wc *wc)
{
struct ib_device *dev;
@@ -966,6 +1034,10 @@ static void srp_handle_recv(struct srp_target_port
*target, struct ib_wc *wc)
PFX "Got target logout request\n");
break;
+ case SRP_CRED_REQ:
+ srp_handle_req(target, iu);
+ break;
+
default:
shost_printk(KERN_WARNING, target->scsi_host,
PFX "Unhandled SRP opcode 0x%02x\n", opcode);
@@ -1022,6 +1094,10 @@ static int srp_compl_thread(void *target_ptr)
return 0;
}
+/*
+ * Must be called with target->scsi_host->host_lock held to protect
+ * tx_tail, tx_rsp and tx_req.
+ */
static void srp_send_completion(struct ib_cq *cq, void *target_ptr)
{
struct srp_target_port *target = target_ptr;
@@ -1037,22 +1113,26 @@ static void srp_send_completion(struct ib_cq *cq, void
*target_ptr)
}
++target->tx_tail;
+ if (wc.wr_id & SRP_OP_RSP)
+ --target->tx_rsp;
+ else
+ --target->tx_req;
}
}
/*
* Must be called with target->scsi_host->host_lock held to protect
- * req_lim and tx_head. Lock cannot be dropped between call here and
- * call to __srp_post_send().
+ * req_lim, tx_head and tx_req. Lock cannot be dropped between call here and
+ * call to __srp_post_send_iu().
*/
-static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target,
- enum srp_request_type req_type)
+static struct srp_iu *__srp_get_tx_req_iu(struct srp_target_port *target,
+ enum srp_request_type req_type)
{
s32 min = (req_type == SRP_REQ_TASK_MGMT) ? 1 : 2;
srp_send_completion(target->send_cq, target);
- if (target->tx_head - target->tx_tail >= SRP_REQ_SQ_SIZE)
+ if (target->tx_req >= SRP_REQ_SQ_SIZE)
return NULL;
if (target->req_lim < min) {
@@ -1065,10 +1145,21 @@ static struct srp_iu *__srp_get_tx_iu(struct
srp_target_port *target,
/*
* Must be called with target->scsi_host->host_lock held to protect
- * req_lim and tx_head.
+ * req_lim, tx_head and tx_req. Lock cannot be dropped between call here and
+ * call to __srp_post_send_iu().
*/
-static int __srp_post_send(struct srp_target_port *target,
- struct srp_iu *iu, int len)
+static struct srp_iu *__srp_get_tx_rsp_iu(struct srp_target_port *target)
+{
+ srp_send_completion(target->send_cq, target);
+
+ if (target->tx_rsp >= SRP_RSP_SQ_SIZE)
+ return NULL;
+
+ return target->tx_ring[target->tx_head & SRP_SQ_MASK];
+}
+
+static int __srp_post_send_iu(struct srp_target_port *target,
+ struct srp_iu *iu, int len, int wr_id_flags)
{
struct ib_sge list;
struct ib_send_wr wr, *bad_wr;
@@ -1079,7 +1170,7 @@ static int __srp_post_send(struct srp_target_port *target,
list.lkey = target->srp_host->srp_dev->mr->lkey;
wr.next = NULL;
- wr.wr_id = target->tx_head & SRP_SQ_MASK;
+ wr.wr_id = (target->tx_head & SRP_SQ_MASK) | wr_id_flags;
wr.sg_list = &list;
wr.num_sge = 1;
wr.opcode = IB_WR_SEND;
@@ -1087,11 +1178,41 @@ static int __srp_post_send(struct srp_target_port
*target,
ret = ib_post_send(target->qp, &wr, &bad_wr);
- if (!ret) {
+ if (!ret)
++target->tx_head;
+
+ return ret;
+}
+
+/*
+ * Must be called with target->scsi_host->host_lock held to protect
+ * req_lim, tx_head and tx_req.
+ */
+static int __srp_post_send_req(struct srp_target_port *target,
+ struct srp_iu *iu, int len)
+{
+ int ret;
+
+ ret = __srp_post_send_iu(target, iu, len, 0);
+ if (ret == 0) {
+ ++target->tx_req;
--target->req_lim;
}
+ return ret;
+}
+
+/*
+ * Must be called with target->scsi_host->host_lock held to protect
+ * tx_head and tx_rsp.
+ */
+static int __srp_post_send_rsp(struct srp_target_port *target,
+ struct srp_iu *iu, int len)
+{
+ int ret;
+ ret = __srp_post_send_iu(target, iu, len, SRP_OP_RSP);
+ if (ret == 0)
+ ++target->tx_rsp;
return ret;
}
@@ -1115,7 +1236,7 @@ static int srp_queuecommand(struct scsi_cmnd *scmnd,
return 0;
}
- iu = __srp_get_tx_iu(target, SRP_REQ_NORMAL);
+ iu = __srp_get_tx_req_iu(target, SRP_REQ_NORMAL);
if (!iu)
goto err;
@@ -1152,7 +1273,7 @@ static int srp_queuecommand(struct scsi_cmnd *scmnd,
ib_dma_sync_single_for_device(dev, iu->dma, srp_max_iu_len,
DMA_TO_DEVICE);
- if (__srp_post_send(target, iu, len)) {
+ if (__srp_post_send_req(target, iu, len)) {
shost_printk(KERN_ERR, target->scsi_host, PFX "Send failed\n");
goto err_unmap;
}
@@ -1422,7 +1543,7 @@ static int srp_send_tsk_mgmt(struct srp_target_port
*target,
init_completion(&req->done);
- iu = __srp_get_tx_iu(target, SRP_REQ_TASK_MGMT);
+ iu = __srp_get_tx_req_iu(target, SRP_REQ_TASK_MGMT);
if (!iu)
goto out;
@@ -1435,7 +1556,7 @@ static int srp_send_tsk_mgmt(struct srp_target_port
*target,
tsk_mgmt->tsk_mgmt_func = func;
tsk_mgmt->task_tag = req->index;
- if (__srp_post_send(target, iu, sizeof *tsk_mgmt))
+ if (__srp_post_send_req(target, iu, sizeof *tsk_mgmt))
goto out;
req->tsk_mgmt = iu;
diff --git a/drivers/infiniband/ulp/srp/ib_srp.h
b/drivers/infiniband/ulp/srp/ib_srp.h
index 9efff05..f198c0d 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.h
+++ b/drivers/infiniband/ulp/srp/ib_srp.h
@@ -73,6 +73,11 @@ enum {
SRP_FMR_DIRTY_SIZE = SRP_FMR_POOL_SIZE / 4
};
+/* wr_id for marking responses sent by the initiator to the target. */
+enum {
+ SRP_OP_RSP = (1 << 30),
+};
+
enum srp_target_state {
SRP_TARGET_LIVE,
SRP_TARGET_CONNECTING,
@@ -151,6 +156,8 @@ struct srp_target_port {
unsigned tx_head;
unsigned tx_tail;
+ unsigned tx_req;
+ unsigned tx_rsp;
struct srp_iu *tx_ring[SRP_SQ_SIZE];
struct list_head free_reqs;
diff --git a/include/scsi/srp.h b/include/scsi/srp.h
index ad178fa..99bd552 100644
--- a/include/scsi/srp.h
+++ b/include/scsi/srp.h
@@ -239,4 +239,23 @@ struct srp_rsp {
u8 data[0];
} __attribute__((packed));
+/*
+ * The SRP spec defines the size of the CRED_REQ structure to be 16 bytes,
+ * so it needs to be packed to avoid having it padded to 24 bytes on
+ * 64-bit architectures.
+ */
+struct srp_cred_req {
+ u8 opcode;
+ u8 sol_not;
+ u8 reserved[2];
+ __be32 req_lim_delta;
+ u64 tag;
+} __attribute__((packed));
+
+struct srp_cred_rsp {
+ u8 opcode;
+ u8 reserved[7];
+ u64 tag;
+};
+
#endif /* SCSI_SRP_H */
--
1.6.4.2
--
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