static int fast_reg_xdr(struct svcxprt_rdma *xprt,
struct xdr_buf *xdr,
struct svc_rdma_req_map *vec)
{
int sge_no;
u32 sge_bytes;
u32 page_bytes;
u32 page_off;
int page_no = 0;
u8 *frva;
struct svc_rdma_fastreg_mr *frmr;
frmr = svc_rdma_get_frmr(xprt);
if (IS_ERR(frmr))
return -ENOMEM;
vec->frmr = frmr;
/* Skip the RPCRDMA header */
sge_no = 1;
/* Map the head. */
frva = (void *)((unsigned long)(xdr->head[0].iov_base) & PAGE_MASK);
vec->sge[sge_no].iov_base = xdr->head[0].iov_base;
vec->sge[sge_no].iov_len = xdr->head[0].iov_len;
vec->count = 2;
sge_no++;
/* Build the FRMR */
frmr->kva = frva;
frmr->direction = DMA_TO_DEVICE;
frmr->access_flags = 0;
frmr->map_len = PAGE_SIZE;
frmr->page_list_len = 1;
frmr->page_list->page_list[page_no] =
ib_dma_map_single(xprt->sc_cm_id->device,
(void *)xdr->head[0].iov_base,
PAGE_SIZE, DMA_TO_DEVICE);
if (ib_dma_mapping_error(xprt->sc_cm_id->device,
frmr->page_list->page_list[page_no]))
goto fatal_err;
atomic_inc(&xprt->sc_dma_used);
page_off = xdr->page_base;
page_bytes = xdr->page_len + page_off;
if (!page_bytes)
goto encode_tail;
/* Map the pages */
vec->sge[sge_no].iov_base = frva + frmr->map_len + page_off;
vec->sge[sge_no].iov_len = page_bytes;
sge_no++;
while (page_bytes) {
struct page *page;
page = xdr->pages[page_no++];
sge_bytes = min_t(u32, page_bytes, (PAGE_SIZE - page_off));
page_bytes -= sge_bytes;
frmr->page_list->page_list[page_no] =
ib_dma_map_single(xprt->sc_cm_id->device,
page_address(page),
PAGE_SIZE, DMA_TO_DEVICE);
if (ib_dma_mapping_error(xprt->sc_cm_id->device,
frmr->page_list->page_list[page_no]))
goto fatal_err;
atomic_inc(&xprt->sc_dma_used);
page_off = 0; /* reset for next time through loop */
frmr->map_len += PAGE_SIZE;
frmr->page_list_len++;
}
vec->count++;
encode_tail:
/* Map tail */
if (0 == xdr->tail[0].iov_len)
goto done;
vec->count++;
vec->sge[sge_no].iov_len = xdr->tail[0].iov_len;
if (((unsigned long)xdr->tail[0].iov_base & PAGE_MASK) ==
((unsigned long)xdr->head[0].iov_base & PAGE_MASK)) {
/*
* If head and tail use the same page, we don't need
* to map it again.
*/
vec->sge[sge_no].iov_base = xdr->tail[0].iov_base;
} else {
void *va;
/* Map another page for the tail */
page_off = (unsigned long)xdr->tail[0].iov_base & ~PAGE_MASK;
va = (void *)((unsigned long)xdr->tail[0].iov_base & PAGE_MASK);
vec->sge[sge_no].iov_base = frva + frmr->map_len + page_off;
frmr->page_list->page_list[page_no] =
ib_dma_map_single(xprt->sc_cm_id->device, va, PAGE_SIZE,
DMA_TO_DEVICE);
if (ib_dma_mapping_error(xprt->sc_cm_id->device,
frmr->page_list->page_list[page_no]))
goto fatal_err;
atomic_inc(&xprt->sc_dma_used);
frmr->map_len += PAGE_SIZE;
frmr->page_list_len++;
}
done:
if (svc_rdma_fastreg(xprt, frmr))
goto fatal_err;
return 0;
fatal_err:
printk("svcrdma: Error fast registering memory for xprt %p\n", xprt);
vec->frmr = NULL;
svc_rdma_put_frmr(xprt, frmr);
return -EIO;
}
/* Map a read-chunk-list to an XDR and fast register the page-list.
*
* Assumptions:
* - chunk[0] position points to pages[0] at an offset of 0
* - pages[] will be made physically contiguous by creating a one-off memory
* region using the fastreg verb.
* - byte_count is # of bytes in read-chunk-list
* - ch_count is # of chunks in read-chunk-list
*
* Output:
* - sge array pointing into pages[] array.
* - chunk_sge array specifying sge index and count for each
* chunk in the read list
*/
static int fast_reg_read_chunks(struct svcxprt_rdma *xprt,
struct svc_rqst *rqstp,
struct svc_rdma_op_ctxt *head,
struct rpcrdma_msg *rmsgp,
struct svc_rdma_req_map *rpl_map,
struct svc_rdma_req_map *chl_map,
int ch_count,
int byte_count)
{
int page_no;
int ch_no;
u32 offset;
struct rpcrdma_read_chunk *ch;
struct svc_rdma_fastreg_mr *frmr;
int ret = 0;
frmr = svc_rdma_get_frmr(xprt);
if (IS_ERR(frmr))
return -ENOMEM;
head->frmr = frmr;
head->arg.head[0] = rqstp->rq_arg.head[0];
head->arg.tail[0] = rqstp->rq_arg.tail[0];
head->arg.pages = &head->pages[head->count];
head->hdr_count = head->count; /* save count of hdr pages */
head->arg.page_base = 0;
head->arg.page_len = byte_count;
head->arg.len = rqstp->rq_arg.len + byte_count;
head->arg.buflen = rqstp->rq_arg.buflen + byte_count;
/* Fast register the page list */
frmr->kva = page_address(rqstp->rq_arg.pages[0]);
frmr->direction = DMA_FROM_DEVICE;
frmr->access_flags = (IB_ACCESS_LOCAL_WRITE|IB_ACCESS_REMOTE_WRITE);
frmr->map_len = byte_count;
frmr->page_list_len = PAGE_ALIGN(byte_count) >> PAGE_SHIFT;
for (page_no = 0; page_no < frmr->page_list_len; page_no++) {
frmr->page_list->page_list[page_no] =
ib_dma_map_page(xprt->sc_cm_id->device,
rqstp->rq_arg.pages[page_no], 0,
PAGE_SIZE, DMA_FROM_DEVICE);
if (ib_dma_mapping_error(xprt->sc_cm_id->device,
frmr->page_list->page_list[page_no]))
goto fatal_err;
atomic_inc(&xprt->sc_dma_used);
head->arg.pages[page_no] = rqstp->rq_arg.pages[page_no];
}
head->count += page_no;
/* rq_respages points one past arg pages */
rqstp->rq_respages = &rqstp->rq_arg.pages[page_no];
/* Create the reply and chunk maps */
offset = 0;
ch = (struct rpcrdma_read_chunk *)&rmsgp->rm_body.rm_chunks[0];
for (ch_no = 0; ch_no < ch_count; ch_no++) {
rpl_map->sge[ch_no].iov_base = frmr->kva + offset;
rpl_map->sge[ch_no].iov_len = ch->rc_target.rs_length;
chl_map->ch[ch_no].count = 1;
chl_map->ch[ch_no].start = ch_no;
offset += ch->rc_target.rs_length;
ch++;
}
ret = svc_rdma_fastreg(xprt, frmr);
if (ret)
goto fatal_err;
return ch_no;
fatal_err:
printk("svcrdma: error fast registering xdr for xprt %p", xprt);
svc_rdma_put_frmr(xprt, frmr);
return -EIO;
}
