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path: root/net/sunrpc/xprtrdma/rpc_rdma.c
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Diffstat (limited to 'net/sunrpc/xprtrdma/rpc_rdma.c')
-rw-r--r--net/sunrpc/xprtrdma/rpc_rdma.c413
1 files changed, 268 insertions, 145 deletions
diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
index b86b5fd62d9f..aec3beb93b25 100644
--- a/net/sunrpc/xprtrdma/rpc_rdma.c
+++ b/net/sunrpc/xprtrdma/rpc_rdma.c
@@ -78,8 +78,6 @@ static unsigned int rpcrdma_max_call_header_size(unsigned int maxsegs)
size += rpcrdma_segment_maxsz * sizeof(__be32);
size += sizeof(__be32); /* list discriminator */
- dprintk("RPC: %s: max call header size = %u\n",
- __func__, size);
return size;
}
@@ -100,8 +98,6 @@ static unsigned int rpcrdma_max_reply_header_size(unsigned int maxsegs)
size += maxsegs * rpcrdma_segment_maxsz * sizeof(__be32);
size += sizeof(__be32); /* list discriminator */
- dprintk("RPC: %s: max reply header size = %u\n",
- __func__, size);
return size;
}
@@ -363,8 +359,7 @@ static struct rpcrdma_mr_seg *rpcrdma_mr_prepare(struct rpcrdma_xprt *r_xprt,
out_getmr_err:
trace_xprtrdma_nomrs(req);
xprt_wait_for_buffer_space(&r_xprt->rx_xprt);
- if (r_xprt->rx_ep.rep_connected != -ENODEV)
- schedule_work(&r_xprt->rx_buf.rb_refresh_worker);
+ rpcrdma_mrs_refresh(r_xprt);
return ERR_PTR(-EAGAIN);
}
@@ -393,7 +388,7 @@ static int rpcrdma_encode_read_list(struct rpcrdma_xprt *r_xprt,
unsigned int pos;
int nsegs;
- if (rtype == rpcrdma_noch)
+ if (rtype == rpcrdma_noch_pullup || rtype == rpcrdma_noch_mapped)
goto done;
pos = rqst->rq_snd_buf.head[0].iov_len;
@@ -565,6 +560,7 @@ static void rpcrdma_sendctx_done(struct kref *kref)
*/
void rpcrdma_sendctx_unmap(struct rpcrdma_sendctx *sc)
{
+ struct rpcrdma_regbuf *rb = sc->sc_req->rl_sendbuf;
struct ib_sge *sge;
if (!sc->sc_unmap_count)
@@ -576,7 +572,7 @@ void rpcrdma_sendctx_unmap(struct rpcrdma_sendctx *sc)
*/
for (sge = &sc->sc_sges[2]; sc->sc_unmap_count;
++sge, --sc->sc_unmap_count)
- ib_dma_unmap_page(sc->sc_device, sge->addr, sge->length,
+ ib_dma_unmap_page(rdmab_device(rb), sge->addr, sge->length,
DMA_TO_DEVICE);
kref_put(&sc->sc_req->rl_kref, rpcrdma_sendctx_done);
@@ -589,149 +585,228 @@ static bool rpcrdma_prepare_hdr_sge(struct rpcrdma_xprt *r_xprt,
{
struct rpcrdma_sendctx *sc = req->rl_sendctx;
struct rpcrdma_regbuf *rb = req->rl_rdmabuf;
- struct ib_sge *sge = sc->sc_sges;
+ struct ib_sge *sge = &sc->sc_sges[req->rl_wr.num_sge++];
if (!rpcrdma_regbuf_dma_map(r_xprt, rb))
- goto out_regbuf;
+ return false;
sge->addr = rdmab_addr(rb);
sge->length = len;
sge->lkey = rdmab_lkey(rb);
ib_dma_sync_single_for_device(rdmab_device(rb), sge->addr, sge->length,
DMA_TO_DEVICE);
- sc->sc_wr.num_sge++;
return true;
-
-out_regbuf:
- pr_err("rpcrdma: failed to DMA map a Send buffer\n");
- return false;
}
-/* Prepare the Send SGEs. The head and tail iovec, and each entry
- * in the page list, gets its own SGE.
+/* The head iovec is straightforward, as it is usually already
+ * DMA-mapped. Sync the content that has changed.
*/
-static bool rpcrdma_prepare_msg_sges(struct rpcrdma_xprt *r_xprt,
- struct rpcrdma_req *req,
- struct xdr_buf *xdr,
- enum rpcrdma_chunktype rtype)
+static bool rpcrdma_prepare_head_iov(struct rpcrdma_xprt *r_xprt,
+ struct rpcrdma_req *req, unsigned int len)
{
struct rpcrdma_sendctx *sc = req->rl_sendctx;
- unsigned int sge_no, page_base, len, remaining;
+ struct ib_sge *sge = &sc->sc_sges[req->rl_wr.num_sge++];
struct rpcrdma_regbuf *rb = req->rl_sendbuf;
- struct ib_sge *sge = sc->sc_sges;
- struct page *page, **ppages;
- /* The head iovec is straightforward, as it is already
- * DMA-mapped. Sync the content that has changed.
- */
if (!rpcrdma_regbuf_dma_map(r_xprt, rb))
- goto out_regbuf;
- sc->sc_device = rdmab_device(rb);
- sge_no = 1;
- sge[sge_no].addr = rdmab_addr(rb);
- sge[sge_no].length = xdr->head[0].iov_len;
- sge[sge_no].lkey = rdmab_lkey(rb);
- ib_dma_sync_single_for_device(rdmab_device(rb), sge[sge_no].addr,
- sge[sge_no].length, DMA_TO_DEVICE);
-
- /* If there is a Read chunk, the page list is being handled
- * via explicit RDMA, and thus is skipped here. However, the
- * tail iovec may include an XDR pad for the page list, as
- * well as additional content, and may not reside in the
- * same page as the head iovec.
- */
- if (rtype == rpcrdma_readch) {
- len = xdr->tail[0].iov_len;
+ return false;
- /* Do not include the tail if it is only an XDR pad */
- if (len < 4)
- goto out;
+ sge->addr = rdmab_addr(rb);
+ sge->length = len;
+ sge->lkey = rdmab_lkey(rb);
- page = virt_to_page(xdr->tail[0].iov_base);
- page_base = offset_in_page(xdr->tail[0].iov_base);
+ ib_dma_sync_single_for_device(rdmab_device(rb), sge->addr, sge->length,
+ DMA_TO_DEVICE);
+ return true;
+}
- /* If the content in the page list is an odd length,
- * xdr_write_pages() has added a pad at the beginning
- * of the tail iovec. Force the tail's non-pad content
- * to land at the next XDR position in the Send message.
- */
- page_base += len & 3;
- len -= len & 3;
- goto map_tail;
- }
+/* If there is a page list present, DMA map and prepare an
+ * SGE for each page to be sent.
+ */
+static bool rpcrdma_prepare_pagelist(struct rpcrdma_req *req,
+ struct xdr_buf *xdr)
+{
+ struct rpcrdma_sendctx *sc = req->rl_sendctx;
+ struct rpcrdma_regbuf *rb = req->rl_sendbuf;
+ unsigned int page_base, len, remaining;
+ struct page **ppages;
+ struct ib_sge *sge;
- /* If there is a page list present, temporarily DMA map
- * and prepare an SGE for each page to be sent.
- */
- if (xdr->page_len) {
- ppages = xdr->pages + (xdr->page_base >> PAGE_SHIFT);
- page_base = offset_in_page(xdr->page_base);
- remaining = xdr->page_len;
- while (remaining) {
- sge_no++;
- if (sge_no > RPCRDMA_MAX_SEND_SGES - 2)
- goto out_mapping_overflow;
-
- len = min_t(u32, PAGE_SIZE - page_base, remaining);
- sge[sge_no].addr =
- ib_dma_map_page(rdmab_device(rb), *ppages,
- page_base, len, DMA_TO_DEVICE);
- if (ib_dma_mapping_error(rdmab_device(rb),
- sge[sge_no].addr))
- goto out_mapping_err;
- sge[sge_no].length = len;
- sge[sge_no].lkey = rdmab_lkey(rb);
-
- sc->sc_unmap_count++;
- ppages++;
- remaining -= len;
- page_base = 0;
- }
- }
+ ppages = xdr->pages + (xdr->page_base >> PAGE_SHIFT);
+ page_base = offset_in_page(xdr->page_base);
+ remaining = xdr->page_len;
+ while (remaining) {
+ sge = &sc->sc_sges[req->rl_wr.num_sge++];
+ len = min_t(unsigned int, PAGE_SIZE - page_base, remaining);
+ sge->addr = ib_dma_map_page(rdmab_device(rb), *ppages,
+ page_base, len, DMA_TO_DEVICE);
+ if (ib_dma_mapping_error(rdmab_device(rb), sge->addr))
+ goto out_mapping_err;
- /* The tail iovec is not always constructed in the same
- * page where the head iovec resides (see, for example,
- * gss_wrap_req_priv). To neatly accommodate that case,
- * DMA map it separately.
- */
- if (xdr->tail[0].iov_len) {
- page = virt_to_page(xdr->tail[0].iov_base);
- page_base = offset_in_page(xdr->tail[0].iov_base);
- len = xdr->tail[0].iov_len;
+ sge->length = len;
+ sge->lkey = rdmab_lkey(rb);
-map_tail:
- sge_no++;
- sge[sge_no].addr =
- ib_dma_map_page(rdmab_device(rb), page, page_base, len,
- DMA_TO_DEVICE);
- if (ib_dma_mapping_error(rdmab_device(rb), sge[sge_no].addr))
- goto out_mapping_err;
- sge[sge_no].length = len;
- sge[sge_no].lkey = rdmab_lkey(rb);
sc->sc_unmap_count++;
+ ppages++;
+ remaining -= len;
+ page_base = 0;
}
-out:
- sc->sc_wr.num_sge += sge_no;
- if (sc->sc_unmap_count)
- kref_get(&req->rl_kref);
return true;
-out_regbuf:
- pr_err("rpcrdma: failed to DMA map a Send buffer\n");
+out_mapping_err:
+ trace_xprtrdma_dma_maperr(sge->addr);
return false;
+}
-out_mapping_overflow:
- rpcrdma_sendctx_unmap(sc);
- pr_err("rpcrdma: too many Send SGEs (%u)\n", sge_no);
- return false;
+/* The tail iovec may include an XDR pad for the page list,
+ * as well as additional content, and may not reside in the
+ * same page as the head iovec.
+ */
+static bool rpcrdma_prepare_tail_iov(struct rpcrdma_req *req,
+ struct xdr_buf *xdr,
+ unsigned int page_base, unsigned int len)
+{
+ struct rpcrdma_sendctx *sc = req->rl_sendctx;
+ struct ib_sge *sge = &sc->sc_sges[req->rl_wr.num_sge++];
+ struct rpcrdma_regbuf *rb = req->rl_sendbuf;
+ struct page *page = virt_to_page(xdr->tail[0].iov_base);
+
+ sge->addr = ib_dma_map_page(rdmab_device(rb), page, page_base, len,
+ DMA_TO_DEVICE);
+ if (ib_dma_mapping_error(rdmab_device(rb), sge->addr))
+ goto out_mapping_err;
+
+ sge->length = len;
+ sge->lkey = rdmab_lkey(rb);
+ ++sc->sc_unmap_count;
+ return true;
out_mapping_err:
- rpcrdma_sendctx_unmap(sc);
- trace_xprtrdma_dma_maperr(sge[sge_no].addr);
+ trace_xprtrdma_dma_maperr(sge->addr);
return false;
}
+/* Copy the tail to the end of the head buffer.
+ */
+static void rpcrdma_pullup_tail_iov(struct rpcrdma_xprt *r_xprt,
+ struct rpcrdma_req *req,
+ struct xdr_buf *xdr)
+{
+ unsigned char *dst;
+
+ dst = (unsigned char *)xdr->head[0].iov_base;
+ dst += xdr->head[0].iov_len + xdr->page_len;
+ memmove(dst, xdr->tail[0].iov_base, xdr->tail[0].iov_len);
+ r_xprt->rx_stats.pullup_copy_count += xdr->tail[0].iov_len;
+}
+
+/* Copy pagelist content into the head buffer.
+ */
+static void rpcrdma_pullup_pagelist(struct rpcrdma_xprt *r_xprt,
+ struct rpcrdma_req *req,
+ struct xdr_buf *xdr)
+{
+ unsigned int len, page_base, remaining;
+ struct page **ppages;
+ unsigned char *src, *dst;
+
+ dst = (unsigned char *)xdr->head[0].iov_base;
+ dst += xdr->head[0].iov_len;
+ ppages = xdr->pages + (xdr->page_base >> PAGE_SHIFT);
+ page_base = offset_in_page(xdr->page_base);
+ remaining = xdr->page_len;
+ while (remaining) {
+ src = page_address(*ppages);
+ src += page_base;
+ len = min_t(unsigned int, PAGE_SIZE - page_base, remaining);
+ memcpy(dst, src, len);
+ r_xprt->rx_stats.pullup_copy_count += len;
+
+ ppages++;
+ dst += len;
+ remaining -= len;
+ page_base = 0;
+ }
+}
+
+/* Copy the contents of @xdr into @rl_sendbuf and DMA sync it.
+ * When the head, pagelist, and tail are small, a pull-up copy
+ * is considerably less costly than DMA mapping the components
+ * of @xdr.
+ *
+ * Assumptions:
+ * - the caller has already verified that the total length
+ * of the RPC Call body will fit into @rl_sendbuf.
+ */
+static bool rpcrdma_prepare_noch_pullup(struct rpcrdma_xprt *r_xprt,
+ struct rpcrdma_req *req,
+ struct xdr_buf *xdr)
+{
+ if (unlikely(xdr->tail[0].iov_len))
+ rpcrdma_pullup_tail_iov(r_xprt, req, xdr);
+
+ if (unlikely(xdr->page_len))
+ rpcrdma_pullup_pagelist(r_xprt, req, xdr);
+
+ /* The whole RPC message resides in the head iovec now */
+ return rpcrdma_prepare_head_iov(r_xprt, req, xdr->len);
+}
+
+static bool rpcrdma_prepare_noch_mapped(struct rpcrdma_xprt *r_xprt,
+ struct rpcrdma_req *req,
+ struct xdr_buf *xdr)
+{
+ struct kvec *tail = &xdr->tail[0];
+
+ if (!rpcrdma_prepare_head_iov(r_xprt, req, xdr->head[0].iov_len))
+ return false;
+ if (xdr->page_len)
+ if (!rpcrdma_prepare_pagelist(req, xdr))
+ return false;
+ if (tail->iov_len)
+ if (!rpcrdma_prepare_tail_iov(req, xdr,
+ offset_in_page(tail->iov_base),
+ tail->iov_len))
+ return false;
+
+ if (req->rl_sendctx->sc_unmap_count)
+ kref_get(&req->rl_kref);
+ return true;
+}
+
+static bool rpcrdma_prepare_readch(struct rpcrdma_xprt *r_xprt,
+ struct rpcrdma_req *req,
+ struct xdr_buf *xdr)
+{
+ if (!rpcrdma_prepare_head_iov(r_xprt, req, xdr->head[0].iov_len))
+ return false;
+
+ /* If there is a Read chunk, the page list is being handled
+ * via explicit RDMA, and thus is skipped here.
+ */
+
+ /* Do not include the tail if it is only an XDR pad */
+ if (xdr->tail[0].iov_len > 3) {
+ unsigned int page_base, len;
+
+ /* If the content in the page list is an odd length,
+ * xdr_write_pages() adds a pad at the beginning of
+ * the tail iovec. Force the tail's non-pad content to
+ * land at the next XDR position in the Send message.
+ */
+ page_base = offset_in_page(xdr->tail[0].iov_base);
+ len = xdr->tail[0].iov_len;
+ page_base += len & 3;
+ len -= len & 3;
+ if (!rpcrdma_prepare_tail_iov(req, xdr, page_base, len))
+ return false;
+ kref_get(&req->rl_kref);
+ }
+
+ return true;
+}
+
/**
* rpcrdma_prepare_send_sges - Construct SGEs for a Send WR
* @r_xprt: controlling transport
@@ -742,31 +817,53 @@ out_mapping_err:
*
* Returns 0 on success; otherwise a negative errno is returned.
*/
-int
-rpcrdma_prepare_send_sges(struct rpcrdma_xprt *r_xprt,
- struct rpcrdma_req *req, u32 hdrlen,
- struct xdr_buf *xdr, enum rpcrdma_chunktype rtype)
+inline int rpcrdma_prepare_send_sges(struct rpcrdma_xprt *r_xprt,
+ struct rpcrdma_req *req, u32 hdrlen,
+ struct xdr_buf *xdr,
+ enum rpcrdma_chunktype rtype)
{
int ret;
ret = -EAGAIN;
req->rl_sendctx = rpcrdma_sendctx_get_locked(r_xprt);
if (!req->rl_sendctx)
- goto err;
- req->rl_sendctx->sc_wr.num_sge = 0;
+ goto out_nosc;
req->rl_sendctx->sc_unmap_count = 0;
req->rl_sendctx->sc_req = req;
kref_init(&req->rl_kref);
+ req->rl_wr.wr_cqe = &req->rl_sendctx->sc_cqe;
+ req->rl_wr.sg_list = req->rl_sendctx->sc_sges;
+ req->rl_wr.num_sge = 0;
+ req->rl_wr.opcode = IB_WR_SEND;
ret = -EIO;
if (!rpcrdma_prepare_hdr_sge(r_xprt, req, hdrlen))
- goto err;
- if (rtype != rpcrdma_areadch)
- if (!rpcrdma_prepare_msg_sges(r_xprt, req, xdr, rtype))
- goto err;
+ goto out_unmap;
+
+ switch (rtype) {
+ case rpcrdma_noch_pullup:
+ if (!rpcrdma_prepare_noch_pullup(r_xprt, req, xdr))
+ goto out_unmap;
+ break;
+ case rpcrdma_noch_mapped:
+ if (!rpcrdma_prepare_noch_mapped(r_xprt, req, xdr))
+ goto out_unmap;
+ break;
+ case rpcrdma_readch:
+ if (!rpcrdma_prepare_readch(r_xprt, req, xdr))
+ goto out_unmap;
+ break;
+ case rpcrdma_areadch:
+ break;
+ default:
+ goto out_unmap;
+ }
+
return 0;
-err:
+out_unmap:
+ rpcrdma_sendctx_unmap(req->rl_sendctx);
+out_nosc:
trace_xprtrdma_prepsend_failed(&req->rl_slot, ret);
return ret;
}
@@ -796,6 +893,7 @@ rpcrdma_marshal_req(struct rpcrdma_xprt *r_xprt, struct rpc_rqst *rqst)
struct rpcrdma_req *req = rpcr_to_rdmar(rqst);
struct xdr_stream *xdr = &req->rl_stream;
enum rpcrdma_chunktype rtype, wtype;
+ struct xdr_buf *buf = &rqst->rq_snd_buf;
bool ddp_allowed;
__be32 *p;
int ret;
@@ -853,8 +951,9 @@ rpcrdma_marshal_req(struct rpcrdma_xprt *r_xprt, struct rpc_rqst *rqst)
*/
if (rpcrdma_args_inline(r_xprt, rqst)) {
*p++ = rdma_msg;
- rtype = rpcrdma_noch;
- } else if (ddp_allowed && rqst->rq_snd_buf.flags & XDRBUF_WRITE) {
+ rtype = buf->len < rdmab_length(req->rl_sendbuf) ?
+ rpcrdma_noch_pullup : rpcrdma_noch_mapped;
+ } else if (ddp_allowed && buf->flags & XDRBUF_WRITE) {
*p++ = rdma_msg;
rtype = rpcrdma_readch;
} else {
@@ -863,12 +962,6 @@ rpcrdma_marshal_req(struct rpcrdma_xprt *r_xprt, struct rpc_rqst *rqst)
rtype = rpcrdma_areadch;
}
- /* If this is a retransmit, discard previously registered
- * chunks. Very likely the connection has been replaced,
- * so these registrations are invalid and unusable.
- */
- frwr_recycle(req);
-
/* This implementation supports the following combinations
* of chunk lists in one RPC-over-RDMA Call message:
*
@@ -902,7 +995,7 @@ rpcrdma_marshal_req(struct rpcrdma_xprt *r_xprt, struct rpc_rqst *rqst)
goto out_err;
ret = rpcrdma_prepare_send_sges(r_xprt, req, req->rl_hdrbuf.len,
- &rqst->rq_snd_buf, rtype);
+ buf, rtype);
if (ret)
goto out_err;
@@ -916,6 +1009,40 @@ out_err:
return ret;
}
+static void __rpcrdma_update_cwnd_locked(struct rpc_xprt *xprt,
+ struct rpcrdma_buffer *buf,
+ u32 grant)
+{
+ buf->rb_credits = grant;
+ xprt->cwnd = grant << RPC_CWNDSHIFT;
+}
+
+static void rpcrdma_update_cwnd(struct rpcrdma_xprt *r_xprt, u32 grant)
+{
+ struct rpc_xprt *xprt = &r_xprt->rx_xprt;
+
+ spin_lock(&xprt->transport_lock);
+ __rpcrdma_update_cwnd_locked(xprt, &r_xprt->rx_buf, grant);
+ spin_unlock(&xprt->transport_lock);
+}
+
+/**
+ * rpcrdma_reset_cwnd - Reset the xprt's congestion window
+ * @r_xprt: controlling transport instance
+ *
+ * Prepare @r_xprt for the next connection by reinitializing
+ * its credit grant to one (see RFC 8166, Section 3.3.3).
+ */
+void rpcrdma_reset_cwnd(struct rpcrdma_xprt *r_xprt)
+{
+ struct rpc_xprt *xprt = &r_xprt->rx_xprt;
+
+ spin_lock(&xprt->transport_lock);
+ xprt->cong = 0;
+ __rpcrdma_update_cwnd_locked(xprt, &r_xprt->rx_buf, 1);
+ spin_unlock(&xprt->transport_lock);
+}
+
/**
* rpcrdma_inline_fixup - Scatter inline received data into rqst's iovecs
* @rqst: controlling RPC request
@@ -955,7 +1082,6 @@ rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len, int pad)
curlen = rqst->rq_rcv_buf.head[0].iov_len;
if (curlen > copy_len)
curlen = copy_len;
- trace_xprtrdma_fixup(rqst, copy_len, curlen);
srcp += curlen;
copy_len -= curlen;
@@ -975,8 +1101,6 @@ rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len, int pad)
if (curlen > pagelist_len)
curlen = pagelist_len;
- trace_xprtrdma_fixup_pg(rqst, i, srcp,
- copy_len, curlen);
destp = kmap_atomic(ppages[i]);
memcpy(destp + page_base, srcp, curlen);
flush_dcache_page(ppages[i]);
@@ -1008,6 +1132,8 @@ rpcrdma_inline_fixup(struct rpc_rqst *rqst, char *srcp, int copy_len, int pad)
rqst->rq_private_buf.tail[0].iov_base = srcp;
}
+ if (fixup_copy_count)
+ trace_xprtrdma_fixup(rqst, fixup_copy_count);
return fixup_copy_count;
}
@@ -1356,12 +1482,9 @@ void rpcrdma_reply_handler(struct rpcrdma_rep *rep)
credits = 1; /* don't deadlock */
else if (credits > buf->rb_max_requests)
credits = buf->rb_max_requests;
- if (buf->rb_credits != credits) {
- spin_lock(&xprt->transport_lock);
- buf->rb_credits = credits;
- xprt->cwnd = credits << RPC_CWNDSHIFT;
- spin_unlock(&xprt->transport_lock);
- }
+ if (buf->rb_credits != credits)
+ rpcrdma_update_cwnd(r_xprt, credits);
+ rpcrdma_post_recvs(r_xprt, false);
req = rpcr_to_rdmar(rqst);
if (req->rl_reply) {
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-02 23:44:16 +0000