Implements SRP_CRED_REQ and SRP_AER_REQ, which are information units defined
in the SRP (draft) standard. Adds declarations for the SRP_CRED_REQ,
SRP_CRED_RSP, SRP_AER_REQ and SRP_AER_RSP information units to
include/scsi/srp.h. Changes function definition order in ib_srp in order to
avoid having to add more forward declarations.
Signed-off-by: Bart Van Assche <bvanass...@acm.org>
Cc: Roland Dreier <rola...@cisco.com>
Cc: David Dillow <d...@thedillows.org>
---
drivers/infiniband/ulp/srp/ib_srp.c | 244 ++++++++++++++++++++++++++---------
drivers/infiniband/ulp/srp/ib_srp.h | 7 +-
include/scsi/srp.h | 38 ++++++
3 files changed, 225 insertions(+), 64 deletions(-)
diff --git a/drivers/infiniband/ulp/srp/ib_srp.c
b/drivers/infiniband/ulp/srp/ib_srp.c
index 548ba5d..da62b57 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -896,6 +896,180 @@ 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 held to protect
+ * tx_head. Lock cannot be dropped between call here and call to
+ * __srp_post_send_iu().
+ *
+ * Note:
+ * An upper limit for the number of allocated information units for each
+ * request type is:
+ * - SRP_TX_IU_REQ_NORMAL: SRP_NORMAL_REQ_SQ_SIZE, since the SCSI mid-layer
+ * never queues more than Scsi_Host.can_queue requests.
+ * - SRP_TX_IU_REQ_TASK_MGMT: SRP_TASK_MGMT_SQ_SIZE.
+ * - SRP_TX_IU_RSP: 1, since a conforming SRP target never sends more than
+ * one unanswered SRP request to an initiator.
+ */
+static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target,
+ enum srp_tx_iu_type tx_iu_type)
+{
+ s32 rsv;
+
+ srp_send_completion(target->send_cq, target);
+
+ rsv = (tx_iu_type == SRP_TX_IU_REQ_TASK_MGMT) ? 0 :
SRP_TASK_MGMT_SQ_SIZE;
+
+ if (target->tx_head - target->tx_tail >= SRP_SQ_SIZE)
+ return NULL;
+
+ if (tx_iu_type != SRP_TX_IU_RSP && target->req_lim <= rsv) {
+ ++target->zero_req_lim;
+ return NULL;
+ }
+
+ return target->tx_ring[target->tx_head & SRP_SQ_MASK];
+}
+
+/*
+ * Must be called with target->scsi_host->host_lock held to protect tx_head.
+ */
+static int __srp_post_send_iu(struct srp_target_port *target,
+ struct srp_iu *iu, int len)
+{
+ struct ib_sge list;
+ struct ib_send_wr wr, *bad_wr;
+ int ret = 0;
+
+ list.addr = iu->dma;
+ list.length = len;
+ list.lkey = target->srp_host->srp_dev->mr->lkey;
+
+ wr.next = NULL;
+ wr.wr_id = target->tx_head & SRP_SQ_MASK;
+ wr.sg_list = &list;
+ wr.num_sge = 1;
+ wr.opcode = IB_WR_SEND;
+ wr.send_flags = IB_SEND_SIGNALED;
+
+ ret = ib_post_send(target->qp, &wr, &bad_wr);
+
+ if (!ret)
+ ++target->tx_head;
+
+ return ret;
+}
+
+/*
+ * Must be called with target->scsi_host->host_lock held to protect req_lim.
+ */
+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);
+ if (ret == 0)
+ --target->req_lim;
+ return ret;
+}
+
+/*
+ * Must be called with target->scsi_host->host_lock held.
+ */
+static int __srp_post_send_rsp(struct srp_target_port *target,
+ struct srp_iu *iu, int len)
+{
+ return __srp_post_send_iu(target, iu, len);
+}
+
+/*
+ * 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;
+}
+
+/*
+ * Must be called with target->scsi_host->host_lock locked to protect
+ * target->req_lim.
+ */
+static int srp_handle_aer_req(struct srp_target_port *target,
+ struct srp_aer_req *req,
+ struct srp_aer_rsp *rsp)
+{
+ target->req_lim += be32_to_cpu(req->req_lim_delta);
+
+ shost_printk(KERN_ERR, target->scsi_host,
+ PFX "ignoring AER for LUN %llu\n", be64_to_cpu(req->lun));
+
+ memset(rsp, 0, sizeof *rsp);
+ rsp->opcode = SRP_AER_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_iu(target, SRP_TX_IU_RSP);
+ 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;
+ case SRP_AER_REQ:
+ res = srp_handle_aer_req(target,
+ (struct srp_aer_req *)req_buf,
+ (struct srp_aer_rsp *)rsp_buf);
+ break;
+ }
+
+ if (res)
+ goto out_unlock;
+
+ 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;
@@ -929,6 +1103,11 @@ 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:
+ case SRP_AER_REQ:
+ srp_handle_req(target, iu);
+ break;
+
default:
shost_printk(KERN_WARNING, target->scsi_host,
PFX "Unhandled SRP opcode 0x%02x\n", opcode);
@@ -981,63 +1160,6 @@ static void srp_send_completion(struct ib_cq *cq, void
*target_ptr)
}
}
-/*
- * 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().
- */
-static struct srp_iu *__srp_get_tx_iu(struct srp_target_port *target,
- enum srp_request_type req_type)
-{
- s32 rsv;
-
- rsv = (req_type == SRP_REQ_TASK_MGMT) ? 0 : SRP_TASK_MGMT_SQ_SIZE;
-
- srp_send_completion(target->send_cq, target);
-
- if (target->tx_head - target->tx_tail >= SRP_SQ_SIZE)
- return NULL;
-
- if (target->req_lim <= rsv) {
- ++target->zero_req_lim;
- return NULL;
- }
-
- return target->tx_ring[target->tx_head & SRP_SQ_MASK];
-}
-
-/*
- * Must be called with target->scsi_host->host_lock held to protect
- * req_lim and tx_head.
- */
-static int __srp_post_send(struct srp_target_port *target,
- struct srp_iu *iu, int len)
-{
- struct ib_sge list;
- struct ib_send_wr wr, *bad_wr;
- int ret = 0;
-
- list.addr = iu->dma;
- list.length = len;
- list.lkey = target->srp_host->srp_dev->mr->lkey;
-
- wr.next = NULL;
- wr.wr_id = target->tx_head & SRP_SQ_MASK;
- wr.sg_list = &list;
- wr.num_sge = 1;
- wr.opcode = IB_WR_SEND;
- wr.send_flags = IB_SEND_SIGNALED;
-
- ret = ib_post_send(target->qp, &wr, &bad_wr);
-
- if (!ret) {
- ++target->tx_head;
- --target->req_lim;
- }
-
- return ret;
-}
-
static int srp_queuecommand(struct scsi_cmnd *scmnd,
void (*done)(struct scsi_cmnd *))
{
@@ -1058,7 +1180,7 @@ static int srp_queuecommand(struct scsi_cmnd *scmnd,
return 0;
}
- iu = __srp_get_tx_iu(target, SRP_REQ_NORMAL);
+ iu = __srp_get_tx_iu(target, SRP_TX_IU_REQ_NORMAL);
if (!iu)
goto err;
@@ -1095,7 +1217,7 @@ 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;
}
@@ -1365,7 +1487,7 @@ 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_iu(target, SRP_TX_IU_REQ_TASK_MGMT);
if (!iu)
goto out;
@@ -1378,7 +1500,7 @@ 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 3a566a7..f8e9bb4 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.h
+++ b/drivers/infiniband/ulp/srp/ib_srp.h
@@ -82,9 +82,10 @@ enum srp_target_state {
SRP_TARGET_REMOVED
};
-enum srp_request_type {
- SRP_REQ_NORMAL,
- SRP_REQ_TASK_MGMT,
+enum srp_tx_iu_type {
+ SRP_TX_IU_REQ_NORMAL,
+ SRP_TX_IU_REQ_TASK_MGMT,
+ SRP_TX_IU_RSP,
};
struct srp_device {
diff --git a/include/scsi/srp.h b/include/scsi/srp.h
index ad178fa..1ae84db 100644
--- a/include/scsi/srp.h
+++ b/include/scsi/srp.h
@@ -239,4 +239,42 @@ struct srp_rsp {
u8 data[0];
} __attribute__((packed));
+struct srp_cred_req {
+ u8 opcode;
+ u8 sol_not;
+ u8 reserved[2];
+ __be32 req_lim_delta;
+ u64 tag;
+};
+
+struct srp_cred_rsp {
+ u8 opcode;
+ u8 reserved[7];
+ u64 tag;
+};
+
+/*
+ * The SRP spec defines the fixed portion of the AER_REQ structure to be
+ * 36 bytes, so it needs to be packed to avoid having it padded to 40 bytes
+ * on 64-bit architectures.
+ */
+struct srp_aer_req {
+ u8 opcode;
+ u8 sol_not;
+ u8 reserved[2];
+ __be32 req_lim_delta;
+ u64 tag;
+ u32 reserved2;
+ __be64 lun;
+ __be32 sense_data_len;
+ u32 reserved3;
+ u8 sense_data[0];
+} __attribute__((packed));
+
+struct srp_aer_rsp {
+ u8 opcode;
+ u8 reserved[7];
+ u64 tag;
+};
+
#endif /* SCSI_SRP_H */
--
1.6.4.2
--
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