RDMA/srpt: Add support for immediate data

Modify allocation of the non-SRQ receive queues such that immediate
data is aligned on a 512 byte boundary. That alignment is necessary
to pass the immediate data without copying to the block layer. When
receiving an SRP_CMD with immediate data, postpone the ib_post_recv()
call until target_execute_cmd() has finished. See also
srpt_release_cmd().

Cc: Sergey Gorenko <sergeygo@mellanox.com>
Cc: Max Gurtovoy <maxg@mellanox.com>
Cc: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This commit is contained in:
Bart Van Assche 2018-12-17 13:20:46 -08:00 committed by Doug Ledford
parent 82305f8235
commit 5dabcd0456
2 changed files with 189 additions and 49 deletions

View file

@ -648,24 +648,26 @@ static void srpt_unregister_mad_agent(struct srpt_device *sdev)
* srpt_alloc_ioctx - allocate a SRPT I/O context structure
* @sdev: SRPT HCA pointer.
* @ioctx_size: I/O context size.
* @dma_size: Size of I/O context DMA buffer.
* @buf_cache: I/O buffer cache.
* @dir: DMA data direction.
*/
static struct srpt_ioctx *srpt_alloc_ioctx(struct srpt_device *sdev,
int ioctx_size, int dma_size,
int ioctx_size,
struct kmem_cache *buf_cache,
enum dma_data_direction dir)
{
struct srpt_ioctx *ioctx;
ioctx = kmalloc(ioctx_size, GFP_KERNEL);
ioctx = kzalloc(ioctx_size, GFP_KERNEL);
if (!ioctx)
goto err;
ioctx->buf = kmalloc(dma_size, GFP_KERNEL);
ioctx->buf = kmem_cache_alloc(buf_cache, GFP_KERNEL);
if (!ioctx->buf)
goto err_free_ioctx;
ioctx->dma = ib_dma_map_single(sdev->device, ioctx->buf, dma_size, dir);
ioctx->dma = ib_dma_map_single(sdev->device, ioctx->buf,
kmem_cache_size(buf_cache), dir);
if (ib_dma_mapping_error(sdev->device, ioctx->dma))
goto err_free_buf;
@ -683,17 +685,19 @@ err:
* srpt_free_ioctx - free a SRPT I/O context structure
* @sdev: SRPT HCA pointer.
* @ioctx: I/O context pointer.
* @dma_size: Size of I/O context DMA buffer.
* @buf_cache: I/O buffer cache.
* @dir: DMA data direction.
*/
static void srpt_free_ioctx(struct srpt_device *sdev, struct srpt_ioctx *ioctx,
int dma_size, enum dma_data_direction dir)
struct kmem_cache *buf_cache,
enum dma_data_direction dir)
{
if (!ioctx)
return;
ib_dma_unmap_single(sdev->device, ioctx->dma, dma_size, dir);
kfree(ioctx->buf);
ib_dma_unmap_single(sdev->device, ioctx->dma,
kmem_cache_size(buf_cache), dir);
kmem_cache_free(buf_cache, ioctx->buf);
kfree(ioctx);
}
@ -702,12 +706,16 @@ static void srpt_free_ioctx(struct srpt_device *sdev, struct srpt_ioctx *ioctx,
* @sdev: Device to allocate the I/O context ring for.
* @ring_size: Number of elements in the I/O context ring.
* @ioctx_size: I/O context size.
* @dma_size: DMA buffer size.
* @buf_cache: I/O buffer cache.
* @alignment_offset: Offset in each ring buffer at which the SRP information
* unit starts.
* @dir: DMA data direction.
*/
static struct srpt_ioctx **srpt_alloc_ioctx_ring(struct srpt_device *sdev,
int ring_size, int ioctx_size,
int dma_size, enum dma_data_direction dir)
struct kmem_cache *buf_cache,
int alignment_offset,
enum dma_data_direction dir)
{
struct srpt_ioctx **ring;
int i;
@ -719,16 +727,17 @@ static struct srpt_ioctx **srpt_alloc_ioctx_ring(struct srpt_device *sdev,
if (!ring)
goto out;
for (i = 0; i < ring_size; ++i) {
ring[i] = srpt_alloc_ioctx(sdev, ioctx_size, dma_size, dir);
ring[i] = srpt_alloc_ioctx(sdev, ioctx_size, buf_cache, dir);
if (!ring[i])
goto err;
ring[i]->index = i;
ring[i]->offset = alignment_offset;
}
goto out;
err:
while (--i >= 0)
srpt_free_ioctx(sdev, ring[i], dma_size, dir);
srpt_free_ioctx(sdev, ring[i], buf_cache, dir);
kvfree(ring);
ring = NULL;
out:
@ -740,12 +749,13 @@ out:
* @ioctx_ring: I/O context ring to be freed.
* @sdev: SRPT HCA pointer.
* @ring_size: Number of ring elements.
* @dma_size: Size of I/O context DMA buffer.
* @buf_cache: I/O buffer cache.
* @dir: DMA data direction.
*/
static void srpt_free_ioctx_ring(struct srpt_ioctx **ioctx_ring,
struct srpt_device *sdev, int ring_size,
int dma_size, enum dma_data_direction dir)
struct kmem_cache *buf_cache,
enum dma_data_direction dir)
{
int i;
@ -753,7 +763,7 @@ static void srpt_free_ioctx_ring(struct srpt_ioctx **ioctx_ring,
return;
for (i = 0; i < ring_size; ++i)
srpt_free_ioctx(sdev, ioctx_ring[i], dma_size, dir);
srpt_free_ioctx(sdev, ioctx_ring[i], buf_cache, dir);
kvfree(ioctx_ring);
}
@ -815,7 +825,7 @@ static int srpt_post_recv(struct srpt_device *sdev, struct srpt_rdma_ch *ch,
struct ib_recv_wr wr;
BUG_ON(!sdev);
list.addr = ioctx->ioctx.dma;
list.addr = ioctx->ioctx.dma + ioctx->ioctx.offset;
list.length = srp_max_req_size;
list.lkey = sdev->lkey;
@ -981,23 +991,28 @@ static inline void *srpt_get_desc_buf(struct srp_cmd *srp_cmd)
/**
* srpt_get_desc_tbl - parse the data descriptors of a SRP_CMD request
* @ioctx: Pointer to the I/O context associated with the request.
* @recv_ioctx: I/O context associated with the received command @srp_cmd.
* @ioctx: I/O context that will be used for responding to the initiator.
* @srp_cmd: Pointer to the SRP_CMD request data.
* @dir: Pointer to the variable to which the transfer direction will be
* written.
* @sg: [out] scatterlist allocated for the parsed SRP_CMD.
* @sg: [out] scatterlist for the parsed SRP_CMD.
* @sg_cnt: [out] length of @sg.
* @data_len: Pointer to the variable to which the total data length of all
* descriptors in the SRP_CMD request will be written.
* @imm_data_offset: [in] Offset in SRP_CMD requests at which immediate data
* starts.
*
* This function initializes ioctx->nrbuf and ioctx->r_bufs.
*
* Returns -EINVAL when the SRP_CMD request contains inconsistent descriptors;
* -ENOMEM when memory allocation fails and zero upon success.
*/
static int srpt_get_desc_tbl(struct srpt_send_ioctx *ioctx,
static int srpt_get_desc_tbl(struct srpt_recv_ioctx *recv_ioctx,
struct srpt_send_ioctx *ioctx,
struct srp_cmd *srp_cmd, enum dma_data_direction *dir,
struct scatterlist **sg, unsigned *sg_cnt, u64 *data_len)
struct scatterlist **sg, unsigned int *sg_cnt, u64 *data_len,
u16 imm_data_offset)
{
BUG_ON(!dir);
BUG_ON(!data_len);
@ -1044,6 +1059,40 @@ static int srpt_get_desc_tbl(struct srpt_send_ioctx *ioctx,
*data_len = be32_to_cpu(idb->len);
return srpt_alloc_rw_ctxs(ioctx, idb->desc_list, nbufs,
sg, sg_cnt);
} else if ((srp_cmd->buf_fmt >> 4) == SRP_DATA_DESC_IMM) {
struct srp_imm_buf *imm_buf = srpt_get_desc_buf(srp_cmd);
void *data = (void *)srp_cmd + imm_data_offset;
uint32_t len = be32_to_cpu(imm_buf->len);
uint32_t req_size = imm_data_offset + len;
if (req_size > srp_max_req_size) {
pr_err("Immediate data (length %d + %d) exceeds request size %d\n",
imm_data_offset, len, srp_max_req_size);
return -EINVAL;
}
if (recv_ioctx->byte_len < req_size) {
pr_err("Received too few data - %d < %d\n",
recv_ioctx->byte_len, req_size);
return -EIO;
}
/*
* The immediate data buffer descriptor must occur before the
* immediate data itself.
*/
if ((void *)(imm_buf + 1) > (void *)data) {
pr_err("Received invalid write request\n");
return -EINVAL;
}
*data_len = len;
ioctx->recv_ioctx = recv_ioctx;
if ((uintptr_t)data & 511) {
pr_warn_once("Internal error - the receive buffers are not aligned properly.\n");
return -EINVAL;
}
sg_init_one(&ioctx->imm_sg, data, len);
*sg = &ioctx->imm_sg;
*sg_cnt = 1;
return 0;
} else {
*data_len = 0;
return 0;
@ -1186,6 +1235,7 @@ static struct srpt_send_ioctx *srpt_get_send_ioctx(struct srpt_rdma_ch *ch)
BUG_ON(ioctx->ch != ch);
ioctx->state = SRPT_STATE_NEW;
WARN_ON_ONCE(ioctx->recv_ioctx);
ioctx->n_rdma = 0;
ioctx->n_rw_ctx = 0;
ioctx->queue_status_only = false;
@ -1428,7 +1478,7 @@ static void srpt_handle_cmd(struct srpt_rdma_ch *ch,
BUG_ON(!send_ioctx);
srp_cmd = recv_ioctx->ioctx.buf;
srp_cmd = recv_ioctx->ioctx.buf + recv_ioctx->ioctx.offset;
cmd = &send_ioctx->cmd;
cmd->tag = srp_cmd->tag;
@ -1448,8 +1498,8 @@ static void srpt_handle_cmd(struct srpt_rdma_ch *ch,
break;
}
rc = srpt_get_desc_tbl(send_ioctx, srp_cmd, &dir, &sg, &sg_cnt,
&data_len);
rc = srpt_get_desc_tbl(recv_ioctx, send_ioctx, srp_cmd, &dir,
&sg, &sg_cnt, &data_len, ch->imm_data_offset);
if (rc) {
if (rc != -EAGAIN) {
pr_err("0x%llx: parsing SRP descriptor table failed.\n",
@ -1516,7 +1566,7 @@ static void srpt_handle_tsk_mgmt(struct srpt_rdma_ch *ch,
BUG_ON(!send_ioctx);
srp_tsk = recv_ioctx->ioctx.buf;
srp_tsk = recv_ioctx->ioctx.buf + recv_ioctx->ioctx.offset;
cmd = &send_ioctx->cmd;
pr_debug("recv tsk_mgmt fn %d for task_tag %lld and cmd tag %lld ch %p sess %p\n",
@ -1559,10 +1609,11 @@ srpt_handle_new_iu(struct srpt_rdma_ch *ch, struct srpt_recv_ioctx *recv_ioctx)
goto push;
ib_dma_sync_single_for_cpu(ch->sport->sdev->device,
recv_ioctx->ioctx.dma, srp_max_req_size,
recv_ioctx->ioctx.dma,
recv_ioctx->ioctx.offset + srp_max_req_size,
DMA_FROM_DEVICE);
srp_cmd = recv_ioctx->ioctx.buf;
srp_cmd = recv_ioctx->ioctx.buf + recv_ioctx->ioctx.offset;
opcode = srp_cmd->opcode;
if (opcode == SRP_CMD || opcode == SRP_TSK_MGMT) {
send_ioctx = srpt_get_send_ioctx(ch);
@ -1599,7 +1650,8 @@ srpt_handle_new_iu(struct srpt_rdma_ch *ch, struct srpt_recv_ioctx *recv_ioctx)
break;
}
srpt_post_recv(ch->sport->sdev, ch, recv_ioctx);
if (!send_ioctx || !send_ioctx->recv_ioctx)
srpt_post_recv(ch->sport->sdev, ch, recv_ioctx);
res = true;
out:
@ -1625,6 +1677,7 @@ static void srpt_recv_done(struct ib_cq *cq, struct ib_wc *wc)
req_lim = atomic_dec_return(&ch->req_lim);
if (unlikely(req_lim < 0))
pr_err("req_lim = %d < 0\n", req_lim);
ioctx->byte_len = wc->byte_len;
srpt_handle_new_iu(ch, ioctx);
} else {
pr_info_ratelimited("receiving failed for ioctx %p with status %d\n",
@ -1749,6 +1802,8 @@ retry:
qp_init->cap.max_rdma_ctxs = sq_size / 2;
qp_init->cap.max_send_sge = min(attrs->max_send_sge,
SRPT_MAX_SG_PER_WQE);
qp_init->cap.max_recv_sge = min(attrs->max_recv_sge,
SRPT_MAX_SG_PER_WQE);
qp_init->port_num = ch->sport->port;
if (sdev->use_srq) {
qp_init->srq = sdev->srq;
@ -2049,11 +2104,15 @@ static void srpt_release_channel_work(struct work_struct *w)
srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_ring,
ch->sport->sdev, ch->rq_size,
ch->max_rsp_size, DMA_TO_DEVICE);
ch->rsp_buf_cache, DMA_TO_DEVICE);
kmem_cache_destroy(ch->rsp_buf_cache);
srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_recv_ring,
sdev, ch->rq_size,
srp_max_req_size, DMA_FROM_DEVICE);
ch->req_buf_cache, DMA_FROM_DEVICE);
kmem_cache_destroy(ch->req_buf_cache);
wake_up(&sport->ch_releaseQ);
@ -2177,14 +2236,19 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
INIT_LIST_HEAD(&ch->cmd_wait_list);
ch->max_rsp_size = ch->sport->port_attrib.srp_max_rsp_size;
ch->rsp_buf_cache = kmem_cache_create("srpt-rsp-buf", ch->max_rsp_size,
512, 0, NULL);
if (!ch->rsp_buf_cache)
goto free_ch;
ch->ioctx_ring = (struct srpt_send_ioctx **)
srpt_alloc_ioctx_ring(ch->sport->sdev, ch->rq_size,
sizeof(*ch->ioctx_ring[0]),
ch->max_rsp_size, DMA_TO_DEVICE);
ch->rsp_buf_cache, 0, DMA_TO_DEVICE);
if (!ch->ioctx_ring) {
pr_err("rejected SRP_LOGIN_REQ because creating a new QP SQ ring failed.\n");
rej->reason = cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
goto free_ch;
goto free_rsp_cache;
}
INIT_LIST_HEAD(&ch->free_list);
@ -2193,16 +2257,39 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
list_add_tail(&ch->ioctx_ring[i]->free_list, &ch->free_list);
}
if (!sdev->use_srq) {
u16 imm_data_offset = req->req_flags & SRP_IMMED_REQUESTED ?
be16_to_cpu(req->imm_data_offset) : 0;
u16 alignment_offset;
u32 req_sz;
if (req->req_flags & SRP_IMMED_REQUESTED)
pr_debug("imm_data_offset = %d\n",
be16_to_cpu(req->imm_data_offset));
if (imm_data_offset >= sizeof(struct srp_cmd)) {
ch->imm_data_offset = imm_data_offset;
rsp->rsp_flags |= SRP_LOGIN_RSP_IMMED_SUPP;
} else {
ch->imm_data_offset = 0;
}
alignment_offset = round_up(imm_data_offset, 512) -
imm_data_offset;
req_sz = alignment_offset + imm_data_offset + srp_max_req_size;
ch->req_buf_cache = kmem_cache_create("srpt-req-buf", req_sz,
512, 0, NULL);
if (!ch->req_buf_cache)
goto free_rsp_ring;
ch->ioctx_recv_ring = (struct srpt_recv_ioctx **)
srpt_alloc_ioctx_ring(ch->sport->sdev, ch->rq_size,
sizeof(*ch->ioctx_recv_ring[0]),
srp_max_req_size,
ch->req_buf_cache,
alignment_offset,
DMA_FROM_DEVICE);
if (!ch->ioctx_recv_ring) {
pr_err("rejected SRP_LOGIN_REQ because creating a new QP RQ ring failed.\n");
rej->reason =
cpu_to_be32(SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
goto free_ring;
goto free_recv_cache;
}
for (i = 0; i < ch->rq_size; i++)
INIT_LIST_HEAD(&ch->ioctx_recv_ring[i]->wait_list);
@ -2252,17 +2339,15 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
if ((req->req_flags & SRP_MTCH_ACTION) == SRP_MULTICHAN_SINGLE) {
struct srpt_rdma_ch *ch2;
rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_NO_CHAN;
list_for_each_entry(ch2, &nexus->ch_list, list) {
if (srpt_disconnect_ch(ch2) < 0)
continue;
pr_info("Relogin - closed existing channel %s\n",
ch2->sess_name);
rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_TERMINATED;
rsp->rsp_flags |= SRP_LOGIN_RSP_MULTICHAN_TERMINATED;
}
} else {
rsp->rsp_flags = SRP_LOGIN_RSP_MULTICHAN_MAINTAINED;
rsp->rsp_flags |= SRP_LOGIN_RSP_MULTICHAN_MAINTAINED;
}
list_add_tail_rcu(&ch->list, &nexus->ch_list);
@ -2292,7 +2377,7 @@ static int srpt_cm_req_recv(struct srpt_device *const sdev,
/* create srp_login_response */
rsp->opcode = SRP_LOGIN_RSP;
rsp->tag = req->tag;
rsp->max_it_iu_len = req->req_it_iu_len;
rsp->max_it_iu_len = cpu_to_be32(srp_max_req_size);
rsp->max_ti_iu_len = req->req_it_iu_len;
ch->max_ti_iu_len = it_iu_len;
rsp->buf_fmt = cpu_to_be16(SRP_BUF_FORMAT_DIRECT |
@ -2356,12 +2441,18 @@ destroy_ib:
free_recv_ring:
srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_recv_ring,
ch->sport->sdev, ch->rq_size,
srp_max_req_size, DMA_FROM_DEVICE);
ch->req_buf_cache, DMA_FROM_DEVICE);
free_ring:
free_recv_cache:
kmem_cache_destroy(ch->req_buf_cache);
free_rsp_ring:
srpt_free_ioctx_ring((struct srpt_ioctx **)ch->ioctx_ring,
ch->sport->sdev, ch->rq_size,
ch->max_rsp_size, DMA_TO_DEVICE);
ch->rsp_buf_cache, DMA_TO_DEVICE);
free_rsp_cache:
kmem_cache_destroy(ch->rsp_buf_cache);
free_ch:
if (rdma_cm_id)
@ -2442,6 +2533,7 @@ static int srpt_rdma_cm_req_recv(struct rdma_cm_id *cm_id,
req.req_flags = req_rdma->req_flags;
memcpy(req.initiator_port_id, req_rdma->initiator_port_id, 16);
memcpy(req.target_port_id, req_rdma->target_port_id, 16);
req.imm_data_offset = req_rdma->imm_data_offset;
snprintf(src_addr, sizeof(src_addr), "%pIS",
&cm_id->route.addr.src_addr);
@ -2632,6 +2724,12 @@ static int srpt_write_pending(struct se_cmd *se_cmd)
enum srpt_command_state new_state;
int ret, i;
if (ioctx->recv_ioctx) {
srpt_set_cmd_state(ioctx, SRPT_STATE_DATA_IN);
target_execute_cmd(&ioctx->cmd);
return 0;
}
new_state = srpt_set_cmd_state(ioctx, SRPT_STATE_NEED_DATA);
WARN_ON(new_state == SRPT_STATE_DONE);
@ -2911,7 +3009,9 @@ static void srpt_free_srq(struct srpt_device *sdev)
ib_destroy_srq(sdev->srq);
srpt_free_ioctx_ring((struct srpt_ioctx **)sdev->ioctx_ring, sdev,
sdev->srq_size, srp_max_req_size, DMA_FROM_DEVICE);
sdev->srq_size, sdev->req_buf_cache,
DMA_FROM_DEVICE);
kmem_cache_destroy(sdev->req_buf_cache);
sdev->srq = NULL;
}
@ -2938,12 +3038,17 @@ static int srpt_alloc_srq(struct srpt_device *sdev)
pr_debug("create SRQ #wr= %d max_allow=%d dev= %s\n", sdev->srq_size,
sdev->device->attrs.max_srq_wr, dev_name(&device->dev));
sdev->req_buf_cache = kmem_cache_create("srpt-srq-req-buf",
srp_max_req_size, 0, 0, NULL);
if (!sdev->req_buf_cache)
goto free_srq;
sdev->ioctx_ring = (struct srpt_recv_ioctx **)
srpt_alloc_ioctx_ring(sdev, sdev->srq_size,
sizeof(*sdev->ioctx_ring[0]),
srp_max_req_size, DMA_FROM_DEVICE);
sdev->req_buf_cache, 0, DMA_FROM_DEVICE);
if (!sdev->ioctx_ring)
goto free_srq;
goto free_cache;
sdev->use_srq = true;
sdev->srq = srq;
@ -2955,6 +3060,9 @@ static int srpt_alloc_srq(struct srpt_device *sdev)
return 0;
free_cache:
kmem_cache_destroy(sdev->req_buf_cache);
free_srq:
ib_destroy_srq(srq);
return -ENOMEM;
@ -3186,11 +3294,18 @@ static void srpt_release_cmd(struct se_cmd *se_cmd)
struct srpt_send_ioctx *ioctx = container_of(se_cmd,
struct srpt_send_ioctx, cmd);
struct srpt_rdma_ch *ch = ioctx->ch;
struct srpt_recv_ioctx *recv_ioctx = ioctx->recv_ioctx;
unsigned long flags;
WARN_ON_ONCE(ioctx->state != SRPT_STATE_DONE &&
!(ioctx->cmd.transport_state & CMD_T_ABORTED));
if (recv_ioctx) {
WARN_ON_ONCE(!list_empty(&recv_ioctx->wait_list));
ioctx->recv_ioctx = NULL;
srpt_post_recv(ch->sport->sdev, ch, recv_ioctx);
}
if (ioctx->n_rw_ctx) {
srpt_free_rw_ctxs(ch, ioctx);
ioctx->n_rw_ctx = 0;

View file

@ -120,11 +120,18 @@ enum {
MAX_SRPT_RDMA_SIZE = 1U << 24,
MAX_SRPT_RSP_SIZE = 1024,
SRP_MAX_ADD_CDB_LEN = 16,
SRP_MAX_IMM_DATA_OFFSET = 80,
SRP_MAX_IMM_DATA = 8 * 1024,
MIN_MAX_REQ_SIZE = 996,
DEFAULT_MAX_REQ_SIZE
= sizeof(struct srp_cmd)/*48*/
+ sizeof(struct srp_indirect_buf)/*20*/
+ 128 * sizeof(struct srp_direct_buf)/*16*/,
DEFAULT_MAX_REQ_SIZE_1 = sizeof(struct srp_cmd)/*48*/ +
SRP_MAX_ADD_CDB_LEN +
sizeof(struct srp_indirect_buf)/*20*/ +
128 * sizeof(struct srp_direct_buf)/*16*/,
DEFAULT_MAX_REQ_SIZE_2 = SRP_MAX_IMM_DATA_OFFSET +
sizeof(struct srp_imm_buf) + SRP_MAX_IMM_DATA,
DEFAULT_MAX_REQ_SIZE = DEFAULT_MAX_REQ_SIZE_1 > DEFAULT_MAX_REQ_SIZE_2 ?
DEFAULT_MAX_REQ_SIZE_1 : DEFAULT_MAX_REQ_SIZE_2,
MIN_MAX_RSP_SIZE = sizeof(struct srp_rsp)/*36*/ + 4,
DEFAULT_MAX_RSP_SIZE = 256, /* leaves 220 bytes for sense data */
@ -161,12 +168,14 @@ enum srpt_command_state {
* @cqe: Completion queue element.
* @buf: Pointer to the buffer.
* @dma: DMA address of the buffer.
* @offset: Offset of the first byte in @buf and @dma that is actually used.
* @index: Index of the I/O context in its ioctx_ring array.
*/
struct srpt_ioctx {
struct ib_cqe cqe;
void *buf;
dma_addr_t dma;
uint32_t offset;
uint32_t index;
};
@ -174,10 +183,12 @@ struct srpt_ioctx {
* struct srpt_recv_ioctx - SRPT receive I/O context
* @ioctx: See above.
* @wait_list: Node for insertion in srpt_rdma_ch.cmd_wait_list.
* @byte_len: Number of bytes in @ioctx.buf.
*/
struct srpt_recv_ioctx {
struct srpt_ioctx ioctx;
struct list_head wait_list;
int byte_len;
};
struct srpt_rw_ctx {
@ -190,8 +201,11 @@ struct srpt_rw_ctx {
* struct srpt_send_ioctx - SRPT send I/O context
* @ioctx: See above.
* @ch: Channel pointer.
* @recv_ioctx: Receive I/O context associated with this send I/O context.
* Only used for processing immediate data.
* @s_rw_ctx: @rw_ctxs points here if only a single rw_ctx is needed.
* @rw_ctxs: RDMA read/write contexts.
* @imm_sg: Scatterlist for immediate data.
* @rdma_cqe: RDMA completion queue element.
* @free_list: Node in srpt_rdma_ch.free_list.
* @state: I/O context state.
@ -205,10 +219,13 @@ struct srpt_rw_ctx {
struct srpt_send_ioctx {
struct srpt_ioctx ioctx;
struct srpt_rdma_ch *ch;
struct srpt_recv_ioctx *recv_ioctx;
struct srpt_rw_ctx s_rw_ctx;
struct srpt_rw_ctx *rw_ctxs;
struct scatterlist imm_sg;
struct ib_cqe rdma_cqe;
struct list_head free_list;
enum srpt_command_state state;
@ -258,12 +275,15 @@ enum rdma_ch_state {
* @req_lim: request limit: maximum number of requests that may be sent
* by the initiator without having received a response.
* @req_lim_delta: Number of credits not yet sent back to the initiator.
* @imm_data_offset: Offset from start of SRP_CMD for immediate data.
* @spinlock: Protects free_list and state.
* @free_list: Head of list with free send I/O contexts.
* @state: channel state. See also enum rdma_ch_state.
* @using_rdma_cm: Whether the RDMA/CM or IB/CM is used for this channel.
* @processing_wait_list: Whether or not cmd_wait_list is being processed.
* @rsp_buf_cache: kmem_cache for @ioctx_ring.
* @ioctx_ring: Send ring.
* @req_buf_cache: kmem_cache for @ioctx_recv_ring.
* @ioctx_recv_ring: Receive I/O context ring.
* @list: Node in srpt_nexus.ch_list.
* @cmd_wait_list: List of SCSI commands that arrived before the RTU event. This
@ -296,10 +316,13 @@ struct srpt_rdma_ch {
int max_ti_iu_len;
atomic_t req_lim;
atomic_t req_lim_delta;
u16 imm_data_offset;
spinlock_t spinlock;
struct list_head free_list;
enum rdma_ch_state state;
struct kmem_cache *rsp_buf_cache;
struct srpt_send_ioctx **ioctx_ring;
struct kmem_cache *req_buf_cache;
struct srpt_recv_ioctx **ioctx_recv_ring;
struct list_head list;
struct list_head cmd_wait_list;
@ -394,6 +417,7 @@ struct srpt_port {
* @srq_size: SRQ size.
* @sdev_mutex: Serializes use_srq changes.
* @use_srq: Whether or not to use SRQ.
* @req_buf_cache: kmem_cache for @ioctx_ring buffers.
* @ioctx_ring: Per-HCA SRQ.
* @event_handler: Per-HCA asynchronous IB event handler.
* @list: Node in srpt_dev_list.
@ -408,6 +432,7 @@ struct srpt_device {
int srq_size;
struct mutex sdev_mutex;
bool use_srq;
struct kmem_cache *req_buf_cache;
struct srpt_recv_ioctx **ioctx_ring;
struct ib_event_handler event_handler;
struct list_head list;