[PATCH 7/9] IB/iser: Use a dedicated descriptor for login

Christoph Hellwig
2015-11-13T13:52:55Z

From: Sagi Grimberg <sagig@mellanox.com>

Makes better sense and we'll need it later with CQ
abstraction.
iser switch login bufs to void

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/infiniband/ulp/iser/iscsi_iser.h | 30 +++++--
drivers/infiniband/ulp/iser/iser_initiator.c | 128 +++++++++++++--------------
drivers/infiniband/ulp/iser/iser_verbs.c | 14 +--
3 files changed, 89 insertions(+), 83 deletions(-)

diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.h b/drivers/infiniband/ulp/iser/iscsi_iser.h
index 502063b..5648409 100644
--- a/drivers/infiniband/ulp/iser/iscsi_iser.h
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.h
@@ -326,6 +326,25 @@ struct iser_rx_desc {
char pad[ISER_RX_PAD_SIZE];
} __attribute__((packed));

+
+/**
+ * struct iser_login_desc - iSER login descriptor
+ *
+ * @req: pointer to login request buffer
+ * @resp: pointer to login response buffer
+ * @req_dma: DMA address of login request buffer
+ * @rsp_dma: DMA address of login response buffer
+ * @sge: IB sge for login post recv
+ */
+struct iser_login_desc {
+ void *req;
+ void *rsp;
+ u64 req_dma;
+ u64 rsp_dma;
+ struct ib_sge sge;
+} __attribute__((packed));
+
+
struct iser_conn;
struct ib_conn;
struct iscsi_iser_task;
@@ -512,11 +531,7 @@ struct ib_conn {
* @up_completion: connection establishment completed
* (state is ISER_CONN_UP)
* @conn_list: entry in ig conn list
- * @login_buf: login data buffer (stores login parameters)
- * @login_req_buf: login request buffer
- * @login_req_dma: login request buffer dma address
- * @login_resp_buf: login response buffer
- * @login_resp_dma: login response buffer dma address
+ * @login_desc: login descriptor
* @rx_desc_head: head of rx_descs cyclic buffer
* @rx_descs: rx buffers array (cyclic buffer)
* @num_rx_descs: number of rx descriptors
@@ -539,10 +554,7 @@ struct iser_conn {
struct completion ib_completion;
struct completion up_completion;
struct list_head conn_list;
-
- char *login_buf;
- char *login_req_buf, *login_resp_buf;
- u64 login_req_dma, login_resp_dma;
+ struct iser_login_desc login_desc;
unsigned int rx_desc_head;
struct iser_rx_desc *rx_descs;
u32 num_rx_descs;
diff --git a/drivers/infiniband/ulp/iser/iser_initiator.c b/drivers/infiniband/ulp/iser/iser_initiator.c
index ffd00c4..21f28c8 100644
--- a/drivers/infiniband/ulp/iser/iser_initiator.c
+++ b/drivers/infiniband/ulp/iser/iser_initiator.c
@@ -174,73 +174,63 @@ static void iser_create_send_desc(struct iser_conn *iser_conn,
static void iser_free_login_buf(struct iser_conn *iser_conn)
{
struct iser_device *device = iser_conn->ib_conn.device;
+ struct iser_login_desc *desc = &iser_conn->login_desc;

- if (!iser_conn->login_buf)
+ if (!desc->req)
return;

- if (iser_conn->login_req_dma)
- ib_dma_unmap_single(device->ib_device,
- iser_conn->login_req_dma,
- ISCSI_DEF_MAX_RECV_SEG_LEN, DMA_TO_DEVICE);
+ ib_dma_unmap_single(device->ib_device, desc->req_dma,
+ ISCSI_DEF_MAX_RECV_SEG_LEN, DMA_TO_DEVICE);

- if (iser_conn->login_resp_dma)
- ib_dma_unmap_single(device->ib_device,
- iser_conn->login_resp_dma,
- ISER_RX_LOGIN_SIZE, DMA_FROM_DEVICE);
+ ib_dma_unmap_single(device->ib_device, desc->rsp_dma,
+ ISER_RX_LOGIN_SIZE, DMA_FROM_DEVICE);

- kfree(iser_conn->login_buf);
+ kfree(desc->req);
+ kfree(desc->rsp);

/* make sure we never redo any unmapping */
- iser_conn->login_req_dma = 0;
- iser_conn->login_resp_dma = 0;
- iser_conn->login_buf = NULL;
+ desc->req = NULL;
+ desc->rsp = NULL;
}

static int iser_alloc_login_buf(struct iser_conn *iser_conn)
{
struct iser_device *device = iser_conn->ib_conn.device;
- int req_err, resp_err;
-
- BUG_ON(device == NULL);
-
- iser_conn->login_buf = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN +
- ISER_RX_LOGIN_SIZE, GFP_KERNEL);
- if (!iser_conn->login_buf)
- goto out_err;
-
- iser_conn->login_req_buf = iser_conn->login_buf;
- iser_conn->login_resp_buf = iser_conn->login_buf +
- ISCSI_DEF_MAX_RECV_SEG_LEN;
-
- iser_conn->login_req_dma = ib_dma_map_single(device->ib_device,
- iser_conn->login_req_buf,
- ISCSI_DEF_MAX_RECV_SEG_LEN,
- DMA_TO_DEVICE);
-
- iser_conn->login_resp_dma = ib_dma_map_single(device->ib_device,
- iser_conn->login_resp_buf,
- ISER_RX_LOGIN_SIZE,
- DMA_FROM_DEVICE);
-
- req_err = ib_dma_mapping_error(device->ib_device,
- iser_conn->login_req_dma);
- resp_err = ib_dma_mapping_error(device->ib_device,
- iser_conn->login_resp_dma);
-
- if (req_err || resp_err) {
- if (req_err)
- iser_conn->login_req_dma = 0;
- if (resp_err)
- iser_conn->login_resp_dma = 0;
- goto free_login_buf;
- }
+ struct iser_login_desc *desc = &iser_conn->login_desc;
+
+ desc->req = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
+ if (!desc->req)
+ return -ENOMEM;
+
+ desc->req_dma = ib_dma_map_single(device->ib_device, desc->req,
+ ISCSI_DEF_MAX_RECV_SEG_LEN,
+ DMA_TO_DEVICE);
+ if (ib_dma_mapping_error(device->ib_device,
+ desc->req_dma))
+ goto free_req;
+
+ desc->rsp = kmalloc(ISER_RX_LOGIN_SIZE, GFP_KERNEL);
+ if (!desc->rsp)
+ goto unmap_req;
+
+ desc->rsp_dma = ib_dma_map_single(device->ib_device, desc->rsp,
+ ISER_RX_LOGIN_SIZE,
+ DMA_FROM_DEVICE);
+ if (ib_dma_mapping_error(device->ib_device,
+ desc->rsp_dma))
+ goto free_rsp;
+
return 0;

-free_login_buf:
- iser_free_login_buf(iser_conn);
+free_rsp:
+ kfree(desc->rsp);
+unmap_req:
+ ib_dma_unmap_single(device->ib_device, desc->req_dma,
+ ISCSI_DEF_MAX_RECV_SEG_LEN,
+ DMA_TO_DEVICE);
+free_req:
+ kfree(desc->req);

-out_err:
- iser_err("unable to alloc or map login buf\n");
return -ENOMEM;
}

@@ -520,25 +510,25 @@ int iser_send_control(struct iscsi_conn *conn,
data_seg_len = ntoh24(task->hdr->dlength);

if (data_seg_len > 0) {
+ struct iser_login_desc *desc = &iser_conn->login_desc;
struct ib_sge *tx_dsg = &mdesc->tx_sg[1];
+
if (task != conn->login_task) {
iser_err("data present on non login task!!!\n");
goto send_control_error;
}

- ib_dma_sync_single_for_cpu(device->ib_device,
- iser_conn->login_req_dma, task->data_count,
- DMA_TO_DEVICE);
+ ib_dma_sync_single_for_cpu(device->ib_device, desc->req_dma,
+ task->data_count, DMA_TO_DEVICE);

- memcpy(iser_conn->login_req_buf, task->data, task->data_count);
+ memcpy(desc->req, task->data, task->data_count);

- ib_dma_sync_single_for_device(device->ib_device,
- iser_conn->login_req_dma, task->data_count,
- DMA_TO_DEVICE);
+ ib_dma_sync_single_for_device(device->ib_device, desc->req_dma,
+ task->data_count, DMA_TO_DEVICE);

- tx_dsg->addr = iser_conn->login_req_dma;
- tx_dsg->length = task->data_count;
- tx_dsg->lkey = device->pd->local_dma_lkey;
+ tx_dsg->addr = desc->req_dma;
+ tx_dsg->length = task->data_count;
+ tx_dsg->lkey = device->pd->local_dma_lkey;
mdesc->num_sge = 2;
}

@@ -572,27 +562,31 @@ void iser_rcv_completion(struct iser_rx_desc *rx_desc,
struct iser_conn *iser_conn = container_of(ib_conn, struct iser_conn,
ib_conn);
struct iscsi_hdr *hdr;
+ char *data;
u64 rx_dma;
int rx_buflen, outstanding, count, err;

/* differentiate between login to all other PDUs */
- if ((char *)rx_desc == iser_conn->login_resp_buf) {
- rx_dma = iser_conn->login_resp_dma;
+ if (rx_desc == (void *)&iser_conn->login_desc) {
+ rx_dma = iser_conn->login_desc.rsp_dma;
rx_buflen = ISER_RX_LOGIN_SIZE;
+ hdr = iser_conn->login_desc.rsp + sizeof(struct iser_hdr);
+ data = iser_conn->login_desc.rsp + ISER_HEADERS_LEN;
} else {
rx_dma = rx_desc->dma_addr;
rx_buflen = ISER_RX_PAYLOAD_SIZE;
+ hdr = &rx_desc->iscsi_header;
+ data = rx_desc->data;
}

ib_dma_sync_single_for_cpu(ib_conn->device->ib_device, rx_dma,
rx_buflen, DMA_FROM_DEVICE);

- hdr = &rx_desc->iscsi_header;

iser_dbg("op 0x%x itt 0x%x dlen %d\n", hdr->opcode,
hdr->itt, (int)(rx_xfer_len - ISER_HEADERS_LEN));

- iscsi_iser_recv(iser_conn->iscsi_conn, hdr, rx_desc->data,
+ iscsi_iser_recv(iser_conn->iscsi_conn, hdr, data,
rx_xfer_len - ISER_HEADERS_LEN);

ib_dma_sync_single_for_device(ib_conn->device->ib_device, rx_dma,
@@ -604,7 +598,7 @@ void iser_rcv_completion(struct iser_rx_desc *rx_desc,
* for the posted rx bufs refcount to become zero handles everything */
ib_conn->post_recv_buf_count--;

- if (rx_dma == iser_conn->login_resp_dma)
+ if (rx_desc == (void *)&iser_conn->login_desc)
return;

outstanding = ib_conn->post_recv_buf_count;
diff --git a/drivers/infiniband/ulp/iser/iser_verbs.c b/drivers/infiniband/ulp/iser/iser_verbs.c
index bf29ddf..ee4cebc 100644
--- a/drivers/infiniband/ulp/iser/iser_verbs.c
+++ b/drivers/infiniband/ulp/iser/iser_verbs.c
@@ -1041,17 +1041,17 @@ int iser_post_recvl(struct iser_conn *iser_conn)
{
struct ib_recv_wr rx_wr, *rx_wr_failed;
struct ib_conn *ib_conn = &iser_conn->ib_conn;
- struct ib_sge sge;
+ struct iser_login_desc *desc = &iser_conn->login_desc;
int ib_ret;

- sge.addr = iser_conn->login_resp_dma;
- sge.length = ISER_RX_LOGIN_SIZE;
- sge.lkey = ib_conn->device->pd->local_dma_lkey;
+ desc->sge.addr = desc->rsp_dma;
+ desc->sge.length = ISER_RX_LOGIN_SIZE;
+ desc->sge.lkey = ib_conn->device->pd->local_dma_lkey;

- rx_wr.wr_id = (uintptr_t)iser_conn->login_resp_buf;
- rx_wr.sg_list = &sge;
+ rx_wr.wr_id = (uintptr_t)desc;
+ rx_wr.sg_list = &desc->sge;
rx_wr.num_sge = 1;
- rx_wr.next = NULL;
+ rx_wr.next = NULL;

ib_conn->post_recv_buf_count++;
ib_ret = ib_post_recv(ib_conn->qp, &rx_wr, &rx_wr_failed);
--
1.9.1