/* Use the ib_map_phys_fmr() verb to register a memory region
* for remote access via RDMA READ or RDMA WRITE.
*/
static int
fmr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg,
int nsegs, bool writing)
{
struct rpcrdma_ia *ia = &r_xprt->rx_ia;
struct ib_device *device = ia->ri_device;
enum dma_data_direction direction = rpcrdma_data_dir(writing);
struct rpcrdma_mr_seg *seg1 = seg;
int len, pageoff, i, rc;
struct rpcrdma_mw *mw;
mw = seg1->rl_mw;
seg1->rl_mw = NULL;
if (!mw) {
mw = rpcrdma_get_mw(r_xprt);
if (!mw)
return -ENOMEM;
} else {
/* this is a retransmit; generate a fresh rkey */
rc = __fmr_unmap(mw);
if (rc)
return rc;
}
pageoff = offset_in_page(seg1->mr_offset);
seg1->mr_offset -= pageoff; /* start of page */
seg1->mr_len += pageoff;
len = -pageoff;
if (nsegs > RPCRDMA_MAX_FMR_SGES)
nsegs = RPCRDMA_MAX_FMR_SGES;
for (i = 0; i < nsegs;) {
rpcrdma_map_one(device, seg, direction);
mw->r.fmr.physaddrs[i] = seg->mr_dma;
len += seg->mr_len;
++seg;
++i;
/* Check for holes */
if ((i < nsegs && offset_in_page(seg->mr_offset)) ||
offset_in_page((seg-1)->mr_offset + (seg-1)->mr_len))
break;
}
rc = ib_map_phys_fmr(mw->r.fmr.fmr, mw->r.fmr.physaddrs,
i, seg1->mr_dma);
if (rc)
goto out_maperr;
seg1->rl_mw = mw;
seg1->mr_rkey = mw->r.fmr.fmr->rkey;
seg1->mr_base = seg1->mr_dma + pageoff;
seg1->mr_nsegs = i;
seg1->mr_len = len;
return i;
out_maperr:
dprintk("RPC: %s: ib_map_phys_fmr %u@0x%llx+%i (%d) status %i\n",
__func__, len, (unsigned long long)seg1->mr_dma,
pageoff, i, rc);
while (i--)
rpcrdma_unmap_one(device, --seg);
return rc;
}
/* Post a REG_MR Work Request to register a memory region
* for remote access via RDMA READ or RDMA WRITE.
*/
static struct rpcrdma_mr_seg *
frwr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg,
int nsegs, bool writing, struct rpcrdma_mr **out)
{
struct rpcrdma_ia *ia = &r_xprt->rx_ia;
bool holes_ok = ia->ri_mrtype == IB_MR_TYPE_SG_GAPS;
struct rpcrdma_frwr *frwr;
struct rpcrdma_mr *mr;
struct ib_mr *ibmr;
struct ib_reg_wr *reg_wr;
struct ib_send_wr *bad_wr;
int rc, i, n;
u8 key;
mr = NULL;
do {
if (mr)
rpcrdma_mr_defer_recovery(mr);
mr = rpcrdma_mr_get(r_xprt);
if (!mr)
return ERR_PTR(-ENOBUFS);
} while (mr->frwr.fr_state != FRWR_IS_INVALID);
frwr = &mr->frwr;
frwr->fr_state = FRWR_IS_VALID;
if (nsegs > ia->ri_max_frwr_depth)
nsegs = ia->ri_max_frwr_depth;
for (i = 0; i < nsegs;) {
if (seg->mr_page)
sg_set_page(&mr->mr_sg[i],
seg->mr_page,
seg->mr_len,
offset_in_page(seg->mr_offset));
else
sg_set_buf(&mr->mr_sg[i], seg->mr_offset,
seg->mr_len);
++seg;
++i;
if (holes_ok)
continue;
if ((i < nsegs && offset_in_page(seg->mr_offset)) ||
offset_in_page((seg-1)->mr_offset + (seg-1)->mr_len))
break;
}
mr->mr_dir = rpcrdma_data_dir(writing);
mr->mr_nents = ib_dma_map_sg(ia->ri_device, mr->mr_sg, i, mr->mr_dir);
if (!mr->mr_nents)
goto out_dmamap_err;
ibmr = frwr->fr_mr;
n = ib_map_mr_sg(ibmr, mr->mr_sg, mr->mr_nents, NULL, PAGE_SIZE);
if (unlikely(n != mr->mr_nents))
goto out_mapmr_err;
key = (u8)(ibmr->rkey & 0x000000FF);
ib_update_fast_reg_key(ibmr, ++key);
reg_wr = &frwr->fr_regwr;
reg_wr->wr.next = NULL;
reg_wr->wr.opcode = IB_WR_REG_MR;
frwr->fr_cqe.done = frwr_wc_fastreg;
reg_wr->wr.wr_cqe = &frwr->fr_cqe;
reg_wr->wr.num_sge = 0;
reg_wr->wr.send_flags = 0;
reg_wr->mr = ibmr;
reg_wr->key = ibmr->rkey;
reg_wr->access = writing ?
IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
IB_ACCESS_REMOTE_READ;
rc = ib_post_send(ia->ri_id->qp, ®_wr->wr, &bad_wr);
if (rc)
goto out_senderr;
mr->mr_handle = ibmr->rkey;
mr->mr_length = ibmr->length;
mr->mr_offset = ibmr->iova;
*out = mr;
return seg;
out_dmamap_err:
pr_err("rpcrdma: failed to DMA map sg %p sg_nents %d\n",
mr->mr_sg, i);
frwr->fr_state = FRWR_IS_INVALID;
rpcrdma_mr_put(mr);
return ERR_PTR(-EIO);
out_mapmr_err:
pr_err("rpcrdma: failed to map mr %p (%d/%d)\n",
frwr->fr_mr, n, mr->mr_nents);
rpcrdma_mr_defer_recovery(mr);
return ERR_PTR(-EIO);
out_senderr:
pr_err("rpcrdma: FRWR registration ib_post_send returned %i\n", rc);
rpcrdma_mr_defer_recovery(mr);
return ERR_PTR(-ENOTCONN);
}
