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authorLinus Torvalds <torvalds@linux-foundation.org>2017-05-10 13:29:23 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-05-10 13:29:23 -0700
commitc70422f760c120480fee4de6c38804c72aa26bc1 (patch)
tree9c61102379bbbf090c13c373ffdace76fe7711ef /net
parent73ccb023a2f25b72c4b95499ca24760588014614 (diff)
parentb26b78cb726007533d81fdf90a62e915002ef5c8 (diff)
downloadlinux-c70422f760c120480fee4de6c38804c72aa26bc1.tar.bz2
Merge tag 'nfsd-4.12' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields: "Another RDMA update from Chuck Lever, and a bunch of miscellaneous bugfixes" * tag 'nfsd-4.12' of git://linux-nfs.org/~bfields/linux: (26 commits) nfsd: Fix up the "supattr_exclcreat" attributes nfsd: encoders mustn't use unitialized values in error cases nfsd: fix undefined behavior in nfsd4_layout_verify lockd: fix lockd shutdown race NFSv4: Fix callback server shutdown SUNRPC: Refactor svc_set_num_threads() NFSv4.x/callback: Create the callback service through svc_create_pooled lockd: remove redundant check on block svcrdma: Clean out old XDR encoders svcrdma: Remove the req_map cache svcrdma: Remove unused RDMA Write completion handler svcrdma: Reduce size of sge array in struct svc_rdma_op_ctxt svcrdma: Clean up RPC-over-RDMA backchannel reply processing svcrdma: Report Write/Reply chunk overruns svcrdma: Clean up RDMA_ERROR path svcrdma: Use rdma_rw API in RPC reply path svcrdma: Introduce local rdma_rw API helpers svcrdma: Clean up svc_rdma_get_inv_rkey() svcrdma: Add helper to save pages under I/O svcrdma: Eliminate RPCRDMA_SQ_DEPTH_MULT ...
Diffstat (limited to 'net')
-rw-r--r--net/sunrpc/Kconfig1
-rw-r--r--net/sunrpc/svc.c134
-rw-r--r--net/sunrpc/xprtrdma/Makefile2
-rw-r--r--net/sunrpc/xprtrdma/svc_rdma.c8
-rw-r--r--net/sunrpc/xprtrdma/svc_rdma_backchannel.c71
-rw-r--r--net/sunrpc/xprtrdma/svc_rdma_marshal.c89
-rw-r--r--net/sunrpc/xprtrdma/svc_rdma_recvfrom.c79
-rw-r--r--net/sunrpc/xprtrdma/svc_rdma_rw.c512
-rw-r--r--net/sunrpc/xprtrdma/svc_rdma_sendto.c978
-rw-r--r--net/sunrpc/xprtrdma/svc_rdma_transport.c110
10 files changed, 1197 insertions, 787 deletions
diff --git a/net/sunrpc/Kconfig b/net/sunrpc/Kconfig
index 04ce2c0b660e..ac09ca803296 100644
--- a/net/sunrpc/Kconfig
+++ b/net/sunrpc/Kconfig
@@ -52,6 +52,7 @@ config SUNRPC_XPRT_RDMA
tristate "RPC-over-RDMA transport"
depends on SUNRPC && INFINIBAND && INFINIBAND_ADDR_TRANS
default SUNRPC && INFINIBAND
+ select SG_POOL
help
This option allows the NFS client and server to use RDMA
transports (InfiniBand, iWARP, or RoCE).
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index a08aeb56b8e4..bc0f5a0ecbdc 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -702,59 +702,32 @@ found_pool:
return task;
}
-/*
- * Create or destroy enough new threads to make the number
- * of threads the given number. If `pool' is non-NULL, applies
- * only to threads in that pool, otherwise round-robins between
- * all pools. Caller must ensure that mutual exclusion between this and
- * server startup or shutdown.
- *
- * Destroying threads relies on the service threads filling in
- * rqstp->rq_task, which only the nfs ones do. Assumes the serv
- * has been created using svc_create_pooled().
- *
- * Based on code that used to be in nfsd_svc() but tweaked
- * to be pool-aware.
- */
-int
-svc_set_num_threads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
+/* create new threads */
+static int
+svc_start_kthreads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
{
struct svc_rqst *rqstp;
struct task_struct *task;
struct svc_pool *chosen_pool;
- int error = 0;
unsigned int state = serv->sv_nrthreads-1;
int node;
- if (pool == NULL) {
- /* The -1 assumes caller has done a svc_get() */
- nrservs -= (serv->sv_nrthreads-1);
- } else {
- spin_lock_bh(&pool->sp_lock);
- nrservs -= pool->sp_nrthreads;
- spin_unlock_bh(&pool->sp_lock);
- }
-
- /* create new threads */
- while (nrservs > 0) {
+ do {
nrservs--;
chosen_pool = choose_pool(serv, pool, &state);
node = svc_pool_map_get_node(chosen_pool->sp_id);
rqstp = svc_prepare_thread(serv, chosen_pool, node);
- if (IS_ERR(rqstp)) {
- error = PTR_ERR(rqstp);
- break;
- }
+ if (IS_ERR(rqstp))
+ return PTR_ERR(rqstp);
__module_get(serv->sv_ops->svo_module);
task = kthread_create_on_node(serv->sv_ops->svo_function, rqstp,
node, "%s", serv->sv_name);
if (IS_ERR(task)) {
- error = PTR_ERR(task);
module_put(serv->sv_ops->svo_module);
svc_exit_thread(rqstp);
- break;
+ return PTR_ERR(task);
}
rqstp->rq_task = task;
@@ -763,18 +736,103 @@ svc_set_num_threads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
svc_sock_update_bufs(serv);
wake_up_process(task);
- }
+ } while (nrservs > 0);
+
+ return 0;
+}
+
+
+/* destroy old threads */
+static int
+svc_signal_kthreads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
+{
+ struct task_struct *task;
+ unsigned int state = serv->sv_nrthreads-1;
+
/* destroy old threads */
- while (nrservs < 0 &&
- (task = choose_victim(serv, pool, &state)) != NULL) {
+ do {
+ task = choose_victim(serv, pool, &state);
+ if (task == NULL)
+ break;
send_sig(SIGINT, task, 1);
nrservs++;
+ } while (nrservs < 0);
+
+ return 0;
+}
+
+/*
+ * Create or destroy enough new threads to make the number
+ * of threads the given number. If `pool' is non-NULL, applies
+ * only to threads in that pool, otherwise round-robins between
+ * all pools. Caller must ensure that mutual exclusion between this and
+ * server startup or shutdown.
+ *
+ * Destroying threads relies on the service threads filling in
+ * rqstp->rq_task, which only the nfs ones do. Assumes the serv
+ * has been created using svc_create_pooled().
+ *
+ * Based on code that used to be in nfsd_svc() but tweaked
+ * to be pool-aware.
+ */
+int
+svc_set_num_threads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
+{
+ if (pool == NULL) {
+ /* The -1 assumes caller has done a svc_get() */
+ nrservs -= (serv->sv_nrthreads-1);
+ } else {
+ spin_lock_bh(&pool->sp_lock);
+ nrservs -= pool->sp_nrthreads;
+ spin_unlock_bh(&pool->sp_lock);
}
- return error;
+ if (nrservs > 0)
+ return svc_start_kthreads(serv, pool, nrservs);
+ if (nrservs < 0)
+ return svc_signal_kthreads(serv, pool, nrservs);
+ return 0;
}
EXPORT_SYMBOL_GPL(svc_set_num_threads);
+/* destroy old threads */
+static int
+svc_stop_kthreads(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
+{
+ struct task_struct *task;
+ unsigned int state = serv->sv_nrthreads-1;
+
+ /* destroy old threads */
+ do {
+ task = choose_victim(serv, pool, &state);
+ if (task == NULL)
+ break;
+ kthread_stop(task);
+ nrservs++;
+ } while (nrservs < 0);
+ return 0;
+}
+
+int
+svc_set_num_threads_sync(struct svc_serv *serv, struct svc_pool *pool, int nrservs)
+{
+ if (pool == NULL) {
+ /* The -1 assumes caller has done a svc_get() */
+ nrservs -= (serv->sv_nrthreads-1);
+ } else {
+ spin_lock_bh(&pool->sp_lock);
+ nrservs -= pool->sp_nrthreads;
+ spin_unlock_bh(&pool->sp_lock);
+ }
+
+ if (nrservs > 0)
+ return svc_start_kthreads(serv, pool, nrservs);
+ if (nrservs < 0)
+ return svc_stop_kthreads(serv, pool, nrservs);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(svc_set_num_threads_sync);
+
/*
* Called from a server thread as it's exiting. Caller must hold the "service
* mutex" for the service.
diff --git a/net/sunrpc/xprtrdma/Makefile b/net/sunrpc/xprtrdma/Makefile
index ef19fa42c50f..c1ae8142ab73 100644
--- a/net/sunrpc/xprtrdma/Makefile
+++ b/net/sunrpc/xprtrdma/Makefile
@@ -4,5 +4,5 @@ rpcrdma-y := transport.o rpc_rdma.o verbs.o \
fmr_ops.o frwr_ops.o \
svc_rdma.o svc_rdma_backchannel.o svc_rdma_transport.o \
svc_rdma_marshal.o svc_rdma_sendto.o svc_rdma_recvfrom.o \
- module.o
+ svc_rdma_rw.o module.o
rpcrdma-$(CONFIG_SUNRPC_BACKCHANNEL) += backchannel.o
diff --git a/net/sunrpc/xprtrdma/svc_rdma.c b/net/sunrpc/xprtrdma/svc_rdma.c
index c846ca9f1eba..a4a8f6989ee7 100644
--- a/net/sunrpc/xprtrdma/svc_rdma.c
+++ b/net/sunrpc/xprtrdma/svc_rdma.c
@@ -58,9 +58,9 @@ unsigned int svcrdma_max_requests = RPCRDMA_MAX_REQUESTS;
unsigned int svcrdma_max_bc_requests = RPCRDMA_MAX_BC_REQUESTS;
static unsigned int min_max_requests = 4;
static unsigned int max_max_requests = 16384;
-unsigned int svcrdma_max_req_size = RPCRDMA_MAX_REQ_SIZE;
-static unsigned int min_max_inline = 4096;
-static unsigned int max_max_inline = 65536;
+unsigned int svcrdma_max_req_size = RPCRDMA_DEF_INLINE_THRESH;
+static unsigned int min_max_inline = RPCRDMA_DEF_INLINE_THRESH;
+static unsigned int max_max_inline = RPCRDMA_MAX_INLINE_THRESH;
atomic_t rdma_stat_recv;
atomic_t rdma_stat_read;
@@ -247,8 +247,6 @@ int svc_rdma_init(void)
dprintk("SVCRDMA Module Init, register RPC RDMA transport\n");
dprintk("\tsvcrdma_ord : %d\n", svcrdma_ord);
dprintk("\tmax_requests : %u\n", svcrdma_max_requests);
- dprintk("\tsq_depth : %u\n",
- svcrdma_max_requests * RPCRDMA_SQ_DEPTH_MULT);
dprintk("\tmax_bc_requests : %u\n", svcrdma_max_bc_requests);
dprintk("\tmax_inline : %d\n", svcrdma_max_req_size);
diff --git a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
index ff1df40f0d26..c676ed0efb5a 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
@@ -12,7 +12,17 @@
#undef SVCRDMA_BACKCHANNEL_DEBUG
-int svc_rdma_handle_bc_reply(struct rpc_xprt *xprt, struct rpcrdma_msg *rmsgp,
+/**
+ * svc_rdma_handle_bc_reply - Process incoming backchannel reply
+ * @xprt: controlling backchannel transport
+ * @rdma_resp: pointer to incoming transport header
+ * @rcvbuf: XDR buffer into which to decode the reply
+ *
+ * Returns:
+ * %0 if @rcvbuf is filled in, xprt_complete_rqst called,
+ * %-EAGAIN if server should call ->recvfrom again.
+ */
+int svc_rdma_handle_bc_reply(struct rpc_xprt *xprt, __be32 *rdma_resp,
struct xdr_buf *rcvbuf)
{
struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
@@ -27,13 +37,13 @@ int svc_rdma_handle_bc_reply(struct rpc_xprt *xprt, struct rpcrdma_msg *rmsgp,
p = (__be32 *)src->iov_base;
len = src->iov_len;
- xid = rmsgp->rm_xid;
+ xid = *rdma_resp;
#ifdef SVCRDMA_BACKCHANNEL_DEBUG
pr_info("%s: xid=%08x, length=%zu\n",
__func__, be32_to_cpu(xid), len);
pr_info("%s: RPC/RDMA: %*ph\n",
- __func__, (int)RPCRDMA_HDRLEN_MIN, rmsgp);
+ __func__, (int)RPCRDMA_HDRLEN_MIN, rdma_resp);
pr_info("%s: RPC: %*ph\n",
__func__, (int)len, p);
#endif
@@ -53,7 +63,7 @@ int svc_rdma_handle_bc_reply(struct rpc_xprt *xprt, struct rpcrdma_msg *rmsgp,
goto out_unlock;
memcpy(dst->iov_base, p, len);
- credits = be32_to_cpu(rmsgp->rm_credit);
+ credits = be32_to_cpup(rdma_resp + 2);
if (credits == 0)
credits = 1; /* don't deadlock */
else if (credits > r_xprt->rx_buf.rb_bc_max_requests)
@@ -90,9 +100,9 @@ out_notfound:
* Caller holds the connection's mutex and has already marshaled
* the RPC/RDMA request.
*
- * This is similar to svc_rdma_reply, but takes an rpc_rqst
- * instead, does not support chunks, and avoids blocking memory
- * allocation.
+ * This is similar to svc_rdma_send_reply_msg, but takes a struct
+ * rpc_rqst instead, does not support chunks, and avoids blocking
+ * memory allocation.
*
* XXX: There is still an opportunity to block in svc_rdma_send()
* if there are no SQ entries to post the Send. This may occur if
@@ -101,59 +111,36 @@ out_notfound:
static int svc_rdma_bc_sendto(struct svcxprt_rdma *rdma,
struct rpc_rqst *rqst)
{
- struct xdr_buf *sndbuf = &rqst->rq_snd_buf;
struct svc_rdma_op_ctxt *ctxt;
- struct svc_rdma_req_map *vec;
- struct ib_send_wr send_wr;
int ret;
- vec = svc_rdma_get_req_map(rdma);
- ret = svc_rdma_map_xdr(rdma, sndbuf, vec, false);
- if (ret)
+ ctxt = svc_rdma_get_context(rdma);
+
+ /* rpcrdma_bc_send_request builds the transport header and
+ * the backchannel RPC message in the same buffer. Thus only
+ * one SGE is needed to send both.
+ */
+ ret = svc_rdma_map_reply_hdr(rdma, ctxt, rqst->rq_buffer,
+ rqst->rq_snd_buf.len);
+ if (ret < 0)
goto out_err;
ret = svc_rdma_repost_recv(rdma, GFP_NOIO);
if (ret)
goto out_err;
- ctxt = svc_rdma_get_context(rdma);
- ctxt->pages[0] = virt_to_page(rqst->rq_buffer);
- ctxt->count = 1;
-
- ctxt->direction = DMA_TO_DEVICE;
- ctxt->sge[0].lkey = rdma->sc_pd->local_dma_lkey;
- ctxt->sge[0].length = sndbuf->len;
- ctxt->sge[0].addr =
- ib_dma_map_page(rdma->sc_cm_id->device, ctxt->pages[0], 0,
- sndbuf->len, DMA_TO_DEVICE);
- if (ib_dma_mapping_error(rdma->sc_cm_id->device, ctxt->sge[0].addr)) {
- ret = -EIO;
- goto out_unmap;
- }
- svc_rdma_count_mappings(rdma, ctxt);
-
- memset(&send_wr, 0, sizeof(send_wr));
- ctxt->cqe.done = svc_rdma_wc_send;
- send_wr.wr_cqe = &ctxt->cqe;
- send_wr.sg_list = ctxt->sge;
- send_wr.num_sge = 1;
- send_wr.opcode = IB_WR_SEND;
- send_wr.send_flags = IB_SEND_SIGNALED;
-
- ret = svc_rdma_send(rdma, &send_wr);
- if (ret) {
- ret = -EIO;
+ ret = svc_rdma_post_send_wr(rdma, ctxt, 1, 0);
+ if (ret)
goto out_unmap;
- }
out_err:
- svc_rdma_put_req_map(rdma, vec);
dprintk("svcrdma: %s returns %d\n", __func__, ret);
return ret;
out_unmap:
svc_rdma_unmap_dma(ctxt);
svc_rdma_put_context(ctxt, 1);
+ ret = -EIO;
goto out_err;
}
diff --git a/net/sunrpc/xprtrdma/svc_rdma_marshal.c b/net/sunrpc/xprtrdma/svc_rdma_marshal.c
index 1c4aabf0f657..bdcf7d85a3dc 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_marshal.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_marshal.c
@@ -166,92 +166,3 @@ out_inval:
dprintk("svcrdma: failed to parse transport header\n");
return -EINVAL;
}
-
-int svc_rdma_xdr_encode_error(struct svcxprt_rdma *xprt,
- struct rpcrdma_msg *rmsgp,
- enum rpcrdma_errcode err, __be32 *va)
-{
- __be32 *startp = va;
-
- *va++ = rmsgp->rm_xid;
- *va++ = rmsgp->rm_vers;
- *va++ = xprt->sc_fc_credits;
- *va++ = rdma_error;
- *va++ = cpu_to_be32(err);
- if (err == ERR_VERS) {
- *va++ = rpcrdma_version;
- *va++ = rpcrdma_version;
- }
-
- return (int)((unsigned long)va - (unsigned long)startp);
-}
-
-/**
- * svc_rdma_xdr_get_reply_hdr_length - Get length of Reply transport header
- * @rdma_resp: buffer containing Reply transport header
- *
- * Returns length of transport header, in bytes.
- */
-unsigned int svc_rdma_xdr_get_reply_hdr_len(__be32 *rdma_resp)
-{
- unsigned int nsegs;
- __be32 *p;
-
- p = rdma_resp;
-
- /* RPC-over-RDMA V1 replies never have a Read list. */
- p += rpcrdma_fixed_maxsz + 1;
-
- /* Skip Write list. */
- while (*p++ != xdr_zero) {
- nsegs = be32_to_cpup(p++);
- p += nsegs * rpcrdma_segment_maxsz;
- }
-
- /* Skip Reply chunk. */
- if (*p++ != xdr_zero) {
- nsegs = be32_to_cpup(p++);
- p += nsegs * rpcrdma_segment_maxsz;
- }
-
- return (unsigned long)p - (unsigned long)rdma_resp;
-}
-
-void svc_rdma_xdr_encode_write_list(struct rpcrdma_msg *rmsgp, int chunks)
-{
- struct rpcrdma_write_array *ary;
-
- /* no read-list */
- rmsgp->rm_body.rm_chunks[0] = xdr_zero;
-
- /* write-array discrim */
- ary = (struct rpcrdma_write_array *)
- &rmsgp->rm_body.rm_chunks[1];
- ary->wc_discrim = xdr_one;
- ary->wc_nchunks = cpu_to_be32(chunks);
-
- /* write-list terminator */
- ary->wc_array[chunks].wc_target.rs_handle = xdr_zero;
-
- /* reply-array discriminator */
- ary->wc_array[chunks].wc_target.rs_length = xdr_zero;
-}
-
-void svc_rdma_xdr_encode_reply_array(struct rpcrdma_write_array *ary,
- int chunks)
-{
- ary->wc_discrim = xdr_one;
- ary->wc_nchunks = cpu_to_be32(chunks);
-}
-
-void svc_rdma_xdr_encode_array_chunk(struct rpcrdma_write_array *ary,
- int chunk_no,
- __be32 rs_handle,
- __be64 rs_offset,
- u32 write_len)
-{
- struct rpcrdma_segment *seg = &ary->wc_array[chunk_no].wc_target;
- seg->rs_handle = rs_handle;
- seg->rs_offset = rs_offset;
- seg->rs_length = cpu_to_be32(write_len);
-}
diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
index f7b2daf72a86..27a99bf5b1a6 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
@@ -558,33 +558,85 @@ static void rdma_read_complete(struct svc_rqst *rqstp,
rqstp->rq_arg.buflen = head->arg.buflen;
}
+static void svc_rdma_send_error(struct svcxprt_rdma *xprt,
+ __be32 *rdma_argp, int status)
+{
+ struct svc_rdma_op_ctxt *ctxt;
+ __be32 *p, *err_msgp;
+ unsigned int length;
+ struct page *page;
+ int ret;
+
+ ret = svc_rdma_repost_recv(xprt, GFP_KERNEL);
+ if (ret)
+ return;
+
+ page = alloc_page(GFP_KERNEL);
+ if (!page)
+ return;
+ err_msgp = page_address(page);
+
+ p = err_msgp;
+ *p++ = *rdma_argp;
+ *p++ = *(rdma_argp + 1);
+ *p++ = xprt->sc_fc_credits;
+ *p++ = rdma_error;
+ if (status == -EPROTONOSUPPORT) {
+ *p++ = err_vers;
+ *p++ = rpcrdma_version;
+ *p++ = rpcrdma_version;
+ } else {
+ *p++ = err_chunk;
+ }
+ length = (unsigned long)p - (unsigned long)err_msgp;
+
+ /* Map transport header; no RPC message payload */
+ ctxt = svc_rdma_get_context(xprt);
+ ret = svc_rdma_map_reply_hdr(xprt, ctxt, err_msgp, length);
+ if (ret) {
+ dprintk("svcrdma: Error %d mapping send for protocol error\n",
+ ret);
+ return;
+ }
+
+ ret = svc_rdma_post_send_wr(xprt, ctxt, 1, 0);
+ if (ret) {
+ dprintk("svcrdma: Error %d posting send for protocol error\n",
+ ret);
+ svc_rdma_unmap_dma(ctxt);
+ svc_rdma_put_context(ctxt, 1);
+ }
+}
+
/* By convention, backchannel calls arrive via rdma_msg type
* messages, and never populate the chunk lists. This makes
* the RPC/RDMA header small and fixed in size, so it is
* straightforward to check the RPC header's direction field.
*/
-static bool
-svc_rdma_is_backchannel_reply(struct svc_xprt *xprt, struct rpcrdma_msg *rmsgp)
+static bool svc_rdma_is_backchannel_reply(struct svc_xprt *xprt,
+ __be32 *rdma_resp)
{
- __be32 *p = (__be32 *)rmsgp;
+ __be32 *p;
if (!xprt->xpt_bc_xprt)
return false;
- if (rmsgp->rm_type != rdma_msg)
+ p = rdma_resp + 3;
+ if (*p++ != rdma_msg)
return false;
- if (rmsgp->rm_body.rm_chunks[0] != xdr_zero)
+
+ if (*p++ != xdr_zero)
return false;
- if (rmsgp->rm_body.rm_chunks[1] != xdr_zero)
+ if (*p++ != xdr_zero)
return false;
- if (rmsgp->rm_body.rm_chunks[2] != xdr_zero)
+ if (*p++ != xdr_zero)
return false;
- /* sanity */
- if (p[7] != rmsgp->rm_xid)
+ /* XID sanity */
+ if (*p++ != *rdma_resp)
return false;
/* call direction */
- if (p[8] == cpu_to_be32(RPC_CALL))
+ if (*p == cpu_to_be32(RPC_CALL))
return false;
return true;
@@ -650,8 +702,9 @@ int svc_rdma_recvfrom(struct svc_rqst *rqstp)
goto out_drop;
rqstp->rq_xprt_hlen = ret;
- if (svc_rdma_is_backchannel_reply(xprt, rmsgp)) {
- ret = svc_rdma_handle_bc_reply(xprt->xpt_bc_xprt, rmsgp,
+ if (svc_rdma_is_backchannel_reply(xprt, &rmsgp->rm_xid)) {
+ ret = svc_rdma_handle_bc_reply(xprt->xpt_bc_xprt,
+ &rmsgp->rm_xid,
&rqstp->rq_arg);
svc_rdma_put_context(ctxt, 0);
if (ret)
@@ -686,7 +739,7 @@ complete:
return ret;
out_err:
- svc_rdma_send_error(rdma_xprt, rmsgp, ret);
+ svc_rdma_send_error(rdma_xprt, &rmsgp->rm_xid, ret);
svc_rdma_put_context(ctxt, 0);
return 0;
diff --git a/net/sunrpc/xprtrdma/svc_rdma_rw.c b/net/sunrpc/xprtrdma/svc_rdma_rw.c
new file mode 100644
index 000000000000..0cf620277693
--- /dev/null
+++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c
@@ -0,0 +1,512 @@
+/*
+ * Copyright (c) 2016 Oracle. All rights reserved.
+ *
+ * Use the core R/W API to move RPC-over-RDMA Read and Write chunks.
+ */
+
+#include <linux/sunrpc/rpc_rdma.h>
+#include <linux/sunrpc/svc_rdma.h>
+#include <linux/sunrpc/debug.h>
+
+#include <rdma/rw.h>
+
+#define RPCDBG_FACILITY RPCDBG_SVCXPRT
+
+/* Each R/W context contains state for one chain of RDMA Read or
+ * Write Work Requests.
+ *
+ * Each WR chain handles a single contiguous server-side buffer,
+ * because scatterlist entries after the first have to start on
+ * page alignment. xdr_buf iovecs cannot guarantee alignment.
+ *
+ * Each WR chain handles only one R_key. Each RPC-over-RDMA segment
+ * from a client may contain a unique R_key, so each WR chain moves
+ * up to one segment at a time.
+ *
+ * The scatterlist makes this data structure over 4KB in size. To
+ * make it less likely to fail, and to handle the allocation for
+ * smaller I/O requests without disabling bottom-halves, these
+ * contexts are created on demand, but cached and reused until the
+ * controlling svcxprt_rdma is destroyed.
+ */
+struct svc_rdma_rw_ctxt {
+ struct list_head rw_list;
+ struct rdma_rw_ctx rw_ctx;
+ int rw_nents;
+ struct sg_table rw_sg_table;
+ struct scatterlist rw_first_sgl[0];
+};
+
+static inline struct svc_rdma_rw_ctxt *
+svc_rdma_next_ctxt(struct list_head *list)
+{
+ return list_first_entry_or_null(list, struct svc_rdma_rw_ctxt,
+ rw_list);
+}
+
+static struct svc_rdma_rw_ctxt *
+svc_rdma_get_rw_ctxt(struct svcxprt_rdma *rdma, unsigned int sges)
+{
+ struct svc_rdma_rw_ctxt *ctxt;
+
+ spin_lock(&rdma->sc_rw_ctxt_lock);
+
+ ctxt = svc_rdma_next_ctxt(&rdma->sc_rw_ctxts);
+ if (ctxt) {
+ list_del(&ctxt->rw_list);
+ spin_unlock(&rdma->sc_rw_ctxt_lock);
+ } else {
+ spin_unlock(&rdma->sc_rw_ctxt_lock);
+ ctxt = kmalloc(sizeof(*ctxt) +
+ SG_CHUNK_SIZE * sizeof(struct scatterlist),
+ GFP_KERNEL);
+ if (!ctxt)
+ goto out;
+ INIT_LIST_HEAD(&ctxt->rw_list);
+ }
+
+ ctxt->rw_sg_table.sgl = ctxt->rw_first_sgl;
+ if (sg_alloc_table_chained(&ctxt->rw_sg_table, sges,
+ ctxt->rw_sg_table.sgl)) {
+ kfree(ctxt);
+ ctxt = NULL;
+ }
+out:
+ return ctxt;
+}
+
+static void svc_rdma_put_rw_ctxt(struct svcxprt_rdma *rdma,
+ struct svc_rdma_rw_ctxt *ctxt)
+{
+ sg_free_table_chained(&ctxt->rw_sg_table, true);
+
+ spin_lock(&rdma->sc_rw_ctxt_lock);
+ list_add(&ctxt->rw_list, &rdma->sc_rw_ctxts);
+ spin_unlock(&rdma->sc_rw_ctxt_lock);
+}
+
+/**
+ * svc_rdma_destroy_rw_ctxts - Free accumulated R/W contexts
+ * @rdma: transport about to be destroyed
+ *
+ */
+void svc_rdma_destroy_rw_ctxts(struct svcxprt_rdma *rdma)
+{
+ struct svc_rdma_rw_ctxt *ctxt;
+
+ while ((ctxt = svc_rdma_next_ctxt(&rdma->sc_rw_ctxts)) != NULL) {
+ list_del(&ctxt->rw_list);
+ kfree(ctxt);
+ }
+}
+
+/* A chunk context tracks all I/O for moving one Read or Write
+ * chunk. This is a a set of rdma_rw's that handle data movement
+ * for all segments of one chunk.
+ *
+ * These are small, acquired with a single allocator call, and
+ * no more than one is needed per chunk. They are allocated on
+ * demand, and not cached.
+ */
+struct svc_rdma_chunk_ctxt {
+ struct ib_cqe cc_cqe;
+ struct svcxprt_rdma *cc_rdma;
+ struct list_head cc_rwctxts;
+ int cc_sqecount;
+ enum dma_data_direction cc_dir;
+};
+
+static void svc_rdma_cc_init(struct svcxprt_rdma *rdma,
+ struct svc_rdma_chunk_ctxt *cc,
+ enum dma_data_direction dir)
+{
+ cc->cc_rdma = rdma;
+ svc_xprt_get(&rdma->sc_xprt);
+
+ INIT_LIST_HEAD(&cc->cc_rwctxts);
+ cc->cc_sqecount = 0;
+ cc->cc_dir = dir;
+}
+
+static void svc_rdma_cc_release(struct svc_rdma_chunk_ctxt *cc)
+{
+ struct svcxprt_rdma *rdma = cc->cc_rdma;
+ struct svc_rdma_rw_ctxt *ctxt;
+
+ while ((ctxt = svc_rdma_next_ctxt(&cc->cc_rwctxts)) != NULL) {
+ list_del(&ctxt->rw_list);
+
+ rdma_rw_ctx_destroy(&ctxt->rw_ctx, rdma->sc_qp,
+ rdma->sc_port_num, ctxt->rw_sg_table.sgl,
+ ctxt->rw_nents, cc->cc_dir);
+ svc_rdma_put_rw_ctxt(rdma, ctxt);
+ }
+ svc_xprt_put(&rdma->sc_xprt);
+}
+
+/* State for sending a Write or Reply chunk.
+ * - Tracks progress of writing one chunk over all its segments
+ * - Stores arguments for the SGL constructor functions
+ */
+struct svc_rdma_write_info {
+ /* write state of this chunk */
+ unsigned int wi_seg_off;
+ unsigned int wi_seg_no;
+ unsigned int wi_nsegs;
+ __be32 *wi_segs;
+
+ /* SGL constructor arguments */
+ struct xdr_buf *wi_xdr;
+ unsigned char *wi_base;
+ unsigned int wi_next_off;
+
+ struct svc_rdma_chunk_ctxt wi_cc;
+};
+
+static struct svc_rdma_write_info *
+svc_rdma_write_info_alloc(struct svcxprt_rdma *rdma, __be32 *chunk)
+{
+ struct svc_rdma_write_info *info;
+
+ info = kmalloc(sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return info;
+
+ info->wi_seg_off = 0;
+ info->wi_seg_no = 0;
+ info->wi_nsegs = be32_to_cpup(++chunk);
+ info->wi_segs = ++chunk;
+ svc_rdma_cc_init(rdma, &info->wi_cc, DMA_TO_DEVICE);
+ return info;
+}
+
+static void svc_rdma_write_info_free(struct svc_rdma_write_info *info)
+{
+ svc_rdma_cc_release(&info->wi_cc);
+ kfree(info);
+}
+
+/**
+ * svc_rdma_write_done - Write chunk completion
+ * @cq: controlling Completion Queue
+ * @wc: Work Completion
+ *
+ * Pages under I/O are freed by a subsequent Send completion.
+ */
+static void svc_rdma_write_done(struct ib_cq *cq, struct ib_wc *wc)
+{
+ struct ib_cqe *cqe = wc->wr_cqe;
+ struct svc_rdma_chunk_ctxt *cc =
+ container_of(cqe, struct svc_rdma_chunk_ctxt, cc_cqe);
+ struct svcxprt_rdma *rdma = cc->cc_rdma;
+ struct svc_rdma_write_info *info =
+ container_of(cc, struct svc_rdma_write_info, wi_cc);
+
+ atomic_add(cc->cc_sqecount, &rdma->sc_sq_avail);
+ wake_up(&rdma->sc_send_wait);
+
+ if (unlikely(wc->status != IB_WC_SUCCESS)) {
+ set_bit(XPT_CLOSE, &rdma->sc_xprt.xpt_flags);
+ if (wc->status != IB_WC_WR_FLUSH_ERR)
+ pr_err("svcrdma: write ctx: %s (%u/0x%x)\n",
+ ib_wc_status_msg(wc->status),
+ wc->status, wc->vendor_err);
+ }
+
+ svc_rdma_write_info_free(info);
+}
+
+/* This function sleeps when the transport's Send Queue is congested.
+ *
+ * Assumptions:
+ * - If ib_post_send() succeeds, only one completion is expected,
+ * even if one or more WRs are flushed. This is true when posting
+ * an rdma_rw_ctx or when posting a single signaled WR.
+ */
+static int svc_rdma_post_chunk_ctxt(struct svc_rdma_chunk_ctxt *cc)
+{
+ struct svcxprt_rdma *rdma = cc->cc_rdma;
+ struct svc_xprt *xprt = &rdma->sc_xprt;
+ struct ib_send_wr *first_wr, *bad_wr;
+ struct list_head *tmp;
+ struct ib_cqe *cqe;
+ int ret;
+
+ first_wr = NULL;
+ cqe = &cc->cc_cqe;
+ list_for_each(tmp, &cc->cc_rwctxts) {
+ struct svc_rdma_rw_ctxt *ctxt;
+
+ ctxt = list_entry(tmp, struct svc_rdma_rw_ctxt, rw_list);
+ first_wr = rdma_rw_ctx_wrs(&ctxt->rw_ctx, rdma->sc_qp,
+ rdma->sc_port_num, cqe, first_wr);
+ cqe = NULL;
+ }
+
+ do {
+ if (atomic_sub_return(cc->cc_sqecount,
+ &rdma->sc_sq_avail) > 0) {
+ ret = ib_post_send(rdma->sc_qp, first_wr, &bad_wr);
+ if (ret)
+ break;
+ return 0;
+ }
+
+ atomic_inc(&rdma_stat_sq_starve);
+ atomic_add(cc->cc_sqecount, &rdma->sc_sq_avail);
+ wait_event(rdma->sc_send_wait,
+ atomic_read(&rdma->sc_sq_avail) > cc->cc_sqecount);
+ } while (1);
+
+ pr_err("svcrdma: ib_post_send failed (%d)\n", ret);
+ set_bit(XPT_CLOSE, &xprt->xpt_flags);
+
+ /* If even one was posted, there will be a completion. */
+ if (bad_wr != first_wr)
+ return 0;
+
+ atomic_add(cc->cc_sqecount, &rdma->sc_sq_avail);
+ wake_up(&rdma->sc_send_wait);
+ return -ENOTCONN;
+}
+
+/* Build and DMA-map an SGL that covers one kvec in an xdr_buf
+ */
+static void svc_rdma_vec_to_sg(struct svc_rdma_write_info *info,
+ unsigned int len,
+ struct svc_rdma_rw_ctxt *ctxt)
+{
+ struct scatterlist *sg = ctxt->rw_sg_table.sgl;
+
+ sg_set_buf(&sg[0], info->wi_base, len);
+ info->wi_base += len;
+
+ ctxt->rw_nents = 1;
+}
+
+/* Build and DMA-map an SGL that covers part of an xdr_buf's pagelist.
+ */
+static void svc_rdma_pagelist_to_sg(struct svc_rdma_write_info *info,
+ unsigned int remaining,
+ struct svc_rdma_rw_ctxt *ctxt)
+{
+ unsigned int sge_no, sge_bytes, page_off, page_no;
+ struct xdr_buf *xdr = info->wi_xdr;
+ struct scatterlist *sg;
+ struct page **page;
+
+ page_off = (info->wi_next_off + xdr->page_base) & ~PAGE_MASK;
+ page_no = (info->wi_next_off + xdr->page_base) >> PAGE_SHIFT;
+ page = xdr->pages + page_no;
+ info->wi_next_off += remaining;
+ sg = ctxt->rw_sg_table.sgl;
+ sge_no = 0;
+ do {
+ sge_bytes = min_t(unsigned int, remaining,
+ PAGE_SIZE - page_off);
+ sg_set_page(sg, *page, sge_bytes, page_off);
+
+ remaining -= sge_bytes;
+ sg = sg_next(sg);
+ page_off = 0;
+ sge_no++;
+ page++;
+ } while (remaining);
+
+ ctxt->rw_nents = sge_no;
+}
+
+/* Construct RDMA Write WRs to send a portion of an xdr_buf containing
+ * an RPC Reply.
+ */
+static int
+svc_rdma_build_writes(struct svc_rdma_write_info *info,
+ void (*constructor)(struct svc_rdma_write_info *info,
+ unsigned int len,
+ struct svc_rdma_rw_ctxt *ctxt),
+ unsigned int remaining)
+{
+ struct svc_rdma_chunk_ctxt *cc = &info->wi_cc;
+ struct svcxprt_rdma *rdma = cc->cc_rdma;
+ struct svc_rdma_rw_ctxt *ctxt;
+ __be32 *seg;
+ int ret;
+
+ cc->cc_cqe.done = svc_rdma_write_done;
+ seg = info->wi_segs + info->wi_seg_no * rpcrdma_segment_maxsz;
+ do {
+ unsigned int write_len;
+ u32 seg_length, seg_handle;
+ u64 seg_offset;
+
+ if (info->wi_seg_no >= info->wi_nsegs)
+ goto out_overflow;
+
+ seg_handle = be32_to_cpup(seg);
+ seg_length = be32_to_cpup(seg + 1);
+ xdr_decode_hyper(seg + 2, &seg_offset);
+ seg_offset += info->wi_seg_off;
+
+ write_len = min(remaining, seg_length - info->wi_seg_off);
+ ctxt = svc_rdma_get_rw_ctxt(rdma,
+ (write_len >> PAGE_SHIFT) + 2);
+ if (!ctxt)
+ goto out_noctx;
+
+ constructor(info, write_len, ctxt);
+ ret = rdma_rw_ctx_init(&ctxt->rw_ctx, rdma->sc_qp,
+ rdma->sc_port_num, ctxt->rw_sg_table.sgl,
+ ctxt->rw_nents, 0, seg_offset,
+ seg_handle, DMA_TO_DEVICE);
+ if (ret < 0)
+ goto out_initerr;
+
+ list_add(&ctxt->rw_list, &cc->cc_rwctxts);
+ cc->cc_sqecount += ret;
+ if (write_len == seg_length - info->wi_seg_off) {
+ seg += 4;
+ info->wi_seg_no++;
+ info->wi_seg_off = 0;
+ } else {
+ info->wi_seg_off += write_len;
+ }
+ remaining -= write_len;
+ } while (remaining);
+
+ return 0;
+
+out_overflow:
+ dprintk("svcrdma: inadequate space in Write chunk (%u)\n",
+ info->wi_nsegs);
+ return -E2BIG;
+
+out_noctx:
+ dprintk("svcrdma: no R/W ctxs available\n");
+ return -ENOMEM;
+
+out_initerr:
+ svc_rdma_put_rw_ctxt(rdma, ctxt);
+ pr_err("svcrdma: failed to map pagelist (%d)\n", ret);
+ return -EIO;
+}
+
+/* Send one of an xdr_buf's kvecs by itself. To send a Reply
+ * chunk, the whole RPC Reply is written back to the client.
+ * This function writes either the head or tail of the xdr_buf
+ * containing the Reply.
+ */
+static int svc_rdma_send_xdr_kvec(struct svc_rdma_write_info *info,
+ struct kvec *vec)
+{
+ info->wi_base = vec->iov_base;
+ return svc_rdma_build_writes(info, svc_rdma_vec_to_sg,
+ vec->iov_len);
+}
+
+/* Send an xdr_buf's page list by itself. A Write chunk is
+ * just the page list. a Reply chunk is the head, page list,
+ * and tail. This function is shared between the two types
+ * of chunk.
+ */
+static int svc_rdma_send_xdr_pagelist(struct svc_rdma_write_info *info,
+ struct xdr_buf *xdr)
+{
+ info->wi_xdr = xdr;
+ info->wi_next_off = 0;
+ return svc_rdma_build_writes(info, svc_rdma_pagelist_to_sg,
+ xdr->page_len);
+}
+
+/**
+ * svc_rdma_send_write_chunk - Write all segments in a Write chunk
+ * @rdma: controlling RDMA transport
+ * @wr_ch: Write chunk provided by client
+ * @xdr: xdr_buf containing the data payload
+ *
+ * Returns a non-negative number of bytes the chunk consumed, or
+ * %-E2BIG if the payload was larger than the Write chunk,
+ * %-ENOMEM if rdma_rw context pool was exhausted,
+ * %-ENOTCONN if posting failed (connection is lost),
+ * %-EIO if rdma_rw initialization failed (DMA mapping, etc).
+ */
+int svc_rdma_send_write_chunk(struct svcxprt_rdma *rdma, __be32 *wr_ch,
+ struct xdr_buf *xdr)
+{
+ struct svc_rdma_write_info *info;
+ int ret;
+
+ if (!xdr->page_len)
+ return 0;
+
+ info = svc_rdma_write_info_alloc(rdma, wr_ch);
+ if (!info)
+ return -ENOMEM;
+
+ ret = svc_rdma_send_xdr_pagelist(info, xdr);
+ if (ret < 0)
+ goto out_err;
+
+ ret = svc_rdma_post_chunk_ctxt(&info->wi_cc);
+ if (ret < 0)
+ goto out_err;
+ return xdr->page_len;
+
+out_err:
+ svc_rdma_write_info_free(info);
+ return ret;
+}
+
+/**
+ * svc_rdma_send_reply_chunk - Write all segments in the Reply chunk
+ * @rdma: controlling RDMA transport
+ * @rp_ch: Reply chunk provided by client
+ * @writelist: true if client provided a Write list
+ * @xdr: xdr_buf containing an RPC Reply
+ *
+ * Returns a non-negative number of bytes the chunk consumed, or
+ * %-E2BIG if the payload was larger than the Reply chunk,
+ * %-ENOMEM if rdma_rw context pool was exhausted,
+ * %-ENOTCONN if posting failed (connection is lost),
+ * %-EIO if rdma_rw initialization failed (DMA mapping, etc).
+ */
+int svc_rdma_send_reply_chunk(struct svcxprt_rdma *rdma, __be32 *rp_ch,
+ bool writelist, struct xdr_buf *xdr)
+{
+ struct svc_rdma_write_info *info;
+ int consumed, ret;
+
+ info = svc_rdma_write_info_alloc(rdma, rp_ch);
+ if (!info)
+ return -ENOMEM;
+
+ ret = svc_rdma_send_xdr_kvec(info, &xdr->head[0]);
+ if (ret < 0)
+ goto out_err;
+ consumed = xdr->head[0].iov_len;
+
+ /* Send the page list in the Reply chunk only if the
+ * client did not provide Write chunks.
+ */
+ if (!writelist && xdr->page_len) {
+ ret = svc_rdma_send_xdr_pagelist(info, xdr);
+ if (ret < 0)
+ goto out_err;
+ consumed += xdr->page_len;
+ }
+
+ if (xdr->tail[0].iov_len) {
+ ret = svc_rdma_send_xdr_kvec(info, &xdr->tail[0]);
+ if (ret < 0)
+ goto out_err;
+ consumed += xdr->tail[0].iov_len;
+ }
+
+ ret = svc_rdma_post_chunk_ctxt(&info->wi_cc);
+ if (ret < 0)
+ goto out_err;
+ return consumed;
+
+out_err:
+ svc_rdma_write_info_free(info);
+ return ret;
+}
diff --git a/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
index 515221b16d09..1736337f3a55 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_sendto.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
@@ -1,4 +1,5 @@
/*
+ * Copyright (c) 2016 Oracle. All rights reserved.
* Copyright (c) 2014 Open Grid Computing, Inc. All rights reserved.
* Copyright (c) 2005-2006 Network Appliance, Inc. All rights reserved.
*
@@ -40,6 +41,63 @@
* Author: Tom Tucker <tom@opengridcomputing.com>
*/
+/* Operation
+ *
+ * The main entry point is svc_rdma_sendto. This is called by the
+ * RPC server when an RPC Reply is ready to be transmitted to a client.
+ *
+ * The passed-in svc_rqst contains a struct xdr_buf which holds an
+ * XDR-encoded RPC Reply message. sendto must construct the RPC-over-RDMA
+ * transport header, post all Write WRs needed for this Reply, then post
+ * a Send WR conveying the transport header and the RPC message itself to
+ * the client.
+ *
+ * svc_rdma_sendto must fully transmit the Reply before returning, as
+ * the svc_rqst will be recycled as soon as sendto returns. Remaining
+ * resources referred to by the svc_rqst are also recycled at that time.
+ * Therefore any resources that must remain longer must be detached
+ * from the svc_rqst and released later.
+ *
+ * Page Management
+ *
+ * The I/O that performs Reply transmission is asynchronous, and may
+ * complete well after sendto returns. Thus pages under I/O must be
+ * removed from the svc_rqst before sendto returns.
+ *
+ * The logic here depends on Send Queue and completion ordering. Since
+ * the Send WR is always posted last, it will always complete last. Thus
+ * when it completes, it is guaranteed that all previous Write WRs have
+ * also completed.
+ *
+ * Write WRs are constructed and posted. Each Write segment gets its own
+ * svc_rdma_rw_ctxt, allowing the Write completion handler to find and
+ * DMA-unmap the pages under I/O for that Write segment. The Write
+ * completion handler does not release any pages.
+ *
+ * When the Send WR is constructed, it also gets its own svc_rdma_op_ctxt.
+ * The ownership of all of the Reply's pages are transferred into that
+ * ctxt, the Send WR is posted, and sendto returns.
+ *
+ * The svc_rdma_op_ctxt is presented when the Send WR completes. The
+ * Send completion handler finally releases the Reply's pages.
+ *
+ * This mechanism also assumes that completions on the transport's Send
+ * Completion Queue do not run in parallel. Otherwise a Write completion
+ * and Send completion running at the same time could release pages that
+ * are still DMA-mapped.
+ *
+ * Error Handling
+ *
+ * - If the Send WR is posted successfully, it will either complete
+ * successfully, or get flushed. Either way, the Send completion
+ * handler releases the Reply's pages.
+ * - If the Send WR cannot be not posted, the forward path releases
+ * the Reply's pages.
+ *
+ * This handles the case, without the use of page reference counting,
+ * where two different Write segments send portions of the same page.
+ */
+
#include <linux/sunrpc/debug.h>
#include <linux/sunrpc/rpc_rdma.h>
#include <linux/spinlock.h>
@@ -55,113 +113,141 @@ static u32 xdr_padsize(u32 len)
return (len & 3) ? (4 - (len & 3)) : 0;
}
-int svc_rdma_map_xdr(struct svcxprt_rdma *xprt,
- struct xdr_buf *xdr,
- struct svc_rdma_req_map *vec,
- bool write_chunk_present)
+/* Returns length of transport header, in bytes.
+ */
+static unsigned int svc_rdma_reply_hdr_len(__be32 *rdma_resp)
{
- int sge_no;
- u32 sge_bytes;
- u32 page_bytes;
- u32 page_off;
- int page_no;
-
- if (xdr->len !=
- (xdr->head[0].iov_len + xdr->page_len + xdr->tail[0].iov_len)) {
- pr_err("svcrdma: %s: XDR buffer length error\n", __func__);
- return -EIO;
- }
+ unsigned int nsegs;
+ __be32 *p;
- /* Skip the first sge, this is for the RPCRDMA header */
- sge_no = 1;
+ p = rdma_resp;
+
+ /* RPC-over-RDMA V1 replies never have a Read list. */
+ p += rpcrdma_fixed_maxsz + 1;
- /* Head SGE */
- vec->sge[sge_no].iov_base = xdr->head[0].iov_base;
- vec->sge[sge_no].iov_len = xdr->head[0].iov_len;
- sge_no++;
-
- /* pages SGE */
- page_no = 0;
- page_bytes = xdr->page_len;
- page_off = xdr->page_base;
- while (page_bytes) {
- vec->sge[sge_no].iov_base =
- page_address(xdr->pages[page_no]) + page_off;
- sge_bytes = min_t(u32, page_bytes, (PAGE_SIZE - page_off));
- page_bytes -= sge_bytes;
- vec->sge[sge_no].iov_len = sge_bytes;
-
- sge_no++;
- page_no++;
- page_off = 0; /* reset for next time through loop */
+ /* Skip Write list. */
+ while (*p++ != xdr_zero) {
+ nsegs = be32_to_cpup(p++);
+ p += nsegs * rpcrdma_segment_maxsz;
}
- /* Tail SGE */
- if (xdr->tail[0].iov_len) {
- unsigned char *base = xdr->tail[0].iov_base;
- size_t len = xdr->tail[0].iov_len;
- u32 xdr_pad = xdr_padsize(xdr->page_len);
+ /* Skip Reply chunk. */
+ if (*p++ != xdr_zero) {
+ nsegs = be32_to_cpup(p++);
+ p += nsegs * rpcrdma_segment_maxsz;
+ }
- if (write_chunk_present && xdr_pad) {
- base += xdr_pad;
- len -= xdr_pad;
- }
+ return (unsigned long)p - (unsigned long)rdma_resp;
+}
- if (len) {
- vec->sge[sge_no].iov_base = base;
- vec->sge[sge_no].iov_len = len;
- sge_no++;
+/* One Write chunk is copied from Call transport header to Reply
+ * transport header. Each segment's length field is updated to
+ * reflect number of bytes consumed in the segment.
+ *
+ * Returns number of segments in this chunk.
+ */
+static unsigned int xdr_encode_write_chunk(__be32 *dst, __be32 *src,
+ unsigned int remaining)
+{
+ unsigned int i, nsegs;
+ u32 seg_len;
+
+ /* Write list discriminator */
+ *dst++ = *src++;
+
+ /* number of segments in this chunk */
+ nsegs = be32_to_cpup(src);
+ *dst++ = *src++;
+
+ for (i = nsegs; i; i--) {
+ /* segment's RDMA handle */
+ *dst++ = *src++;
+
+ /* bytes returned in this segment */
+ seg_len = be32_to_cpu(*src);
+ if (remaining >= seg_len) {
+ /* entire segment was consumed */
+ *dst = *src;
+ remaining -= seg_len;
+ } else {
+ /* segment only partly filled */
+ *dst = cpu_to_be32(remaining);
+ remaining = 0;
}
- }
+ dst++; src++;
- dprintk("svcrdma: %s: sge_no %d page_no %d "
- "page_base %u page_len %u head_len %zu tail_len %zu\n",
- __func__, sge_no, page_no, xdr->page_base, xdr->page_len,
- xdr->head[0].iov_len, xdr->tail[0].iov_len);
+ /* segment's RDMA offset */
+ *dst++ = *src++;
+ *dst++ = *src++;
+ }
- vec->count = sge_no;
- return 0;
+ return nsegs;
}
-static dma_addr_t dma_map_xdr(struct svcxprt_rdma *xprt,
- struct xdr_buf *xdr,
- u32 xdr_off, size_t len, int dir)
+/* The client provided a Write list in the Call message. Fill in
+ * the segments in the first Write chunk in the Reply's transport
+ * header with the number of bytes consumed in each segment.
+ * Remaining chunks are returned unused.
+ *
+ * Assumptions:
+ * - Client has provided only one Write chunk
+ */
+static void svc_rdma_xdr_encode_write_list(__be32 *rdma_resp, __be32 *wr_ch,
+ unsigned int consumed)
{
- struct page *page;
- dma_addr_t dma_addr;
- if (xdr_off < xdr->head[0].iov_len) {
- /* This offset is in the head */
- xdr_off += (unsigned long)xdr->head[0].iov_base & ~PAGE_MASK;
- page = virt_to_page(xdr->head[0].iov_base);
- } else {
- xdr_off -= xdr->head[0].iov_len;
- if (xdr_off < xdr->page_len) {
- /* This offset is in the page list */
- xdr_off += xdr->page_base;
- page = xdr->pages[xdr_off >> PAGE_SHIFT];
- xdr_off &= ~PAGE_MASK;
- } else {
- /* This offset is in the tail */
- xdr_off -= xdr->page_len;
- xdr_off += (unsigned long)
- xdr->tail[0].iov_base & ~PAGE_MASK;
- page = virt_to_page(xdr->tail[0].iov_base);
- }
+ unsigned int nsegs;
+ __be32 *p, *q;
+
+ /* RPC-over-RDMA V1 replies never have a Read list. */
+ p = rdma_resp + rpcrdma_fixed_maxsz + 1;
+
+ q = wr_ch;
+ while (*q != xdr_zero) {
+ nsegs = xdr_encode_write_chunk(p, q, consumed);
+ q += 2 + nsegs * rpcrdma_segment_maxsz;
+ p += 2 + nsegs * rpcrdma_segment_maxsz;
+ consumed = 0;
}
- dma_addr = ib_dma_map_page(xprt->sc_cm_id->device, page, xdr_off,
- min_t(size_t, PAGE_SIZE, len), dir);
- return dma_addr;
+
+ /* Terminate Write list */
+ *p++ = xdr_zero;
+
+ /* Reply chunk discriminator; may be replaced later */
+ *p = xdr_zero;
+}
+
+/* The client provided a Reply chunk in the Call message. Fill in
+ * the segments in the Reply chunk in the Reply message with the
+ * number of bytes consumed in each segment.
+ *
+ * Assumptions:
+ * - Reply can always fit in the provided Reply chunk
+ */
+static void svc_rdma_xdr_encode_reply_chunk(__be32 *rdma_resp, __be32 *rp_ch,
+ unsigned int consumed)
+{
+ __be32 *p;
+
+ /* Find the Reply chunk in the Reply's xprt header.
+ * RPC-over-RDMA V1 replies never have a Read list.
+ */
+ p = rdma_resp + rpcrdma_fixed_maxsz + 1;
+
+ /* Skip past Write list */
+ while (*p++ != xdr_zero)
+ p += 1 + be32_to_cpup(p) * rpcrdma_segment_maxsz;
+
+ xdr_encode_write_chunk(p, rp_ch, consumed);
}
/* Parse the RPC Call's transport header.
*/
-static void svc_rdma_get_write_arrays(struct rpcrdma_msg *rmsgp,
- struct rpcrdma_write_array **write,
- struct rpcrdma_write_array **reply)
+static void svc_rdma_get_write_arrays(__be32 *rdma_argp,
+ __be32 **write, __be32 **reply)
{
__be32 *p;
- p = (__be32 *)&rmsgp->rm_body.rm_chunks[0];
+ p = rdma_argp + rpcrdma_fixed_maxsz;
/* Read list */
while (*p++ != xdr_zero)
@@ -169,7 +255,7 @@ static void svc_rdma_get_write_arrays(struct rpcrdma_msg *rmsgp,
/* Write list */
if (*p != xdr_zero) {
- *write = (struct rpcrdma_write_array *)p;
+ *write = p;
while (*p++ != xdr_zero)
p += 1 + be32_to_cpu(*p) * 4;
} else {
@@ -179,7 +265,7 @@ static void svc_rdma_get_write_arrays(struct rpcrdma_msg *rmsgp,
/* Reply chunk */
if (*p != xdr_zero)
- *reply = (struct rpcrdma_write_array *)p;
+ *reply = p;
else
*reply = NULL;
}
@@ -189,360 +275,321 @@ static void svc_rdma_get_write_arrays(struct rpcrdma_msg *rmsgp,
* Invalidate, and responder chooses one rkey to invalidate.
*
* Find a candidate rkey to invalidate when sending a reply. Picks the
- * first rkey it finds in the chunks lists.
+ * first R_key it finds in the chunk lists.
*
* Returns zero if RPC's chunk lists are empty.
*/
-static u32 svc_rdma_get_inv_rkey(struct rpcrdma_msg *rdma_argp,
- struct rpcrdma_write_array *wr_ary,
- struct rpcrdma_write_array *rp_ary)
+static u32 svc_rdma_get_inv_rkey(__be32 *rdma_argp,
+ __be32 *wr_lst, __be32 *rp_ch)
{
- struct rpcrdma_read_chunk *rd_ary;
- struct rpcrdma_segment *arg_ch;
+ __be32 *p;
- rd_ary = (struct rpcrdma_read_chunk *)&rdma_argp->rm_body.rm_chunks[0];
- if (rd_ary->rc_discrim != xdr_zero)
- return be32_to_cpu(rd_ary->rc_target.rs_handle);
+ p = rdma_argp + rpcrdma_fixed_maxsz;
+ if (*p != xdr_zero)
+ p += 2;
+ else if (wr_lst && be32_to_cpup(wr_lst + 1))
+ p = wr_lst + 2;
+ else if (rp_ch && be32_to_cpup(rp_ch + 1))
+ p = rp_ch + 2;
+ else
+ return 0;
+ return be32_to_cpup(p);
+}
- if (wr_ary && be32_to_cpu(wr_ary->wc_nchunks)) {
- arg_ch = &wr_ary->wc_array[0].wc_target;
- return be32_to_cpu(arg_ch->rs_handle);
- }
+/* ib_dma_map_page() is used here because svc_rdma_dma_unmap()
+ * is used during completion to DMA-unmap this memory, and
+ * it uses ib_dma_unmap_page() exclusively.
+ */
+static int svc_rdma_dma_map_buf(struct svcxprt_rdma *rdma,
+ struct svc_rdma_op_ctxt *ctxt,
+ unsigned int sge_no,
+ unsigned char *base,
+ unsigned int len)
+{
+ unsigned long offset = (unsigned long)base & ~PAGE_MASK;
+ struct ib_device *dev = rdma->sc_cm_id->device;
+ dma_addr_t dma_addr;
- if (rp_ary && be32_to_cpu(rp_ary->wc_nchunks)) {
- arg_ch = &rp_ary->wc_array[0].wc_target;
- return be32_to_cpu(arg_ch->rs_handle);
- }
+ dma_addr = ib_dma_map_page(dev, virt_to_page(base),
+ offset, len, DMA_TO_DEVICE);
+ if (ib_dma_mapping_error(dev, dma_addr))
+ return -EIO;
+ ctxt->sge[sge_no].addr = dma_addr;
+ ctxt->sge[sge_no].length = len;
+ ctxt->sge[sge_no].lkey = rdma->sc_pd->local_dma_lkey;
+ svc_rdma_count_mappings(rdma, ctxt);
return 0;
}
-/* Assumptions:
- * - The specified write_len can be represented in sc_max_sge * PAGE_SIZE
- */
-static int send_write(struct svcxprt_rdma *xprt, struct svc_rqst *rqstp,
- u32 rmr, u64 to,
- u32 xdr_off, int write_len,
- struct svc_rdma_req_map *vec)
+static int svc_rdma_dma_map_page(struct svcxprt_rdma *rdma,
+ struct svc_rdma_op_ctxt *ctxt,
+ unsigned int sge_no,
+ struct page *page,
+ unsigned int offset,
+ unsigned int len)
{
- struct ib_rdma_wr write_wr;
- struct ib_sge *sge;
- int xdr_sge_no;
- int sge_no;
- int sge_bytes;
- int sge_off;
- int bc;
- struct svc_rdma_op_ctxt *ctxt;
+ struct ib_device *dev = rdma->sc_cm_id->device;
+ dma_addr_t dma_addr;
- if (vec->count > RPCSVC_MAXPAGES) {
- pr_err("svcrdma: Too many pages (%lu)\n", vec->count);
+ dma_addr = ib_dma_map_page(dev, page, offset, len, DMA_TO_DEVICE);
+ if (ib_dma_mapping_error(dev, dma_addr))
return -EIO;
- }
- dprintk("svcrdma: RDMA_WRITE rmr=%x, to=%llx, xdr_off=%d, "
- "write_len=%d, vec->sge=%p, vec->count=%lu\n",
- rmr, (unsigned long long)to, xdr_off,
- write_len, vec->sge, vec->count);
+ ctxt->sge[sge_no].addr = dma_addr;
+ ctxt->sge[sge_no].length = len;
+ ctxt->sge[sge_no].lkey = rdma->sc_pd->local_dma_lkey;
+ svc_rdma_count_mappings(rdma, ctxt);
+ return 0;
+}
- ctxt = svc_rdma_get_context(xprt);
+/**
+ * svc_rdma_map_reply_hdr - DMA map the transport header buffer
+ * @rdma: controlling transport
+ * @ctxt: op_ctxt for the Send WR
+ * @rdma_resp: buffer containing transport header
+ * @len: length of transport header
+ *
+ * Returns:
+ * %0 if the header is DMA mapped,
+ * %-EIO if DMA mapping failed.
+ */
+int svc_rdma_map_reply_hdr(struct svcxprt_rdma *rdma,
+ struct svc_rdma_op_ctxt *ctxt,
+ __be32 *rdma_resp,
+ unsigned int len)
+{
ctxt->direction = DMA_TO_DEVICE;
- sge = ctxt->sge;
-
- /* Find the SGE associated with xdr_off */
- for (bc = xdr_off, xdr_sge_no = 1; bc && xdr_sge_no < vec->count;
- xdr_sge_no++) {
- if (vec->sge[xdr_sge_no].iov_len > bc)
- break;
- bc -= vec->sge[xdr_sge_no].iov_len;
- }
-
- sge_off = bc;
- bc = write_len;
- sge_no = 0;
-
- /* Copy the remaining SGE */
- while (bc != 0) {
- sge_bytes = min_t(size_t,
- bc, vec->sge[xdr_sge_no].iov_len-sge_off);
- sge[sge_no].length = sge_bytes;
- sge[sge_no].addr =
- dma_map_xdr(xprt, &rqstp->rq_res, xdr_off,
- sge_bytes, DMA_TO_DEVICE);
- xdr_off += sge_bytes;
- if (ib_dma_mapping_error(xprt->sc_cm_id->device,
- sge[sge_no].addr))
- goto err;
- svc_rdma_count_mappings(xprt, ctxt);
- sge[sge_no].lkey = xprt->sc_pd->local_dma_lkey;
- ctxt->count++;
- sge_off = 0;
- sge_no++;
- xdr_sge_no++;
- if (xdr_sge_no > vec->count) {
- pr_err("svcrdma: Too many sges (%d)\n", xdr_sge_no);
- goto err;
- }
- bc -= sge_bytes;
- if (sge_no == xprt->sc_max_sge)
- break;
- }
-
- /* Prepare WRITE WR */
- memset(&write_wr, 0, sizeof write_wr);
- ctxt->cqe.done = svc_rdma_wc_write;
- write_wr.wr.wr_cqe = &ctxt->cqe;
- write_wr.wr.sg_list = &sge[0];
- write_wr.wr.num_sge = sge_no;
- write_wr.wr.opcode = IB_WR_RDMA_WRITE;
- write_wr.wr.send_flags = IB_SEND_SIGNALED;
- write_wr.rkey = rmr;
- write_wr.remote_addr = to;
-
- /* Post It */
- atomic_inc(&rdma_stat_write);
- if (svc_rdma_send(xprt, &write_wr.wr))
- goto err;
- return write_len - bc;
- err:
- svc_rdma_unmap_dma(ctxt);
- svc_rdma_put_context(ctxt, 0);
- return -EIO;
+ ctxt->pages[0] = virt_to_page(rdma_resp);
+ ctxt->count = 1;
+ return svc_rdma_dma_map_page(rdma, ctxt, 0, ctxt->pages[0], 0, len);
}
-noinline
-static int send_write_chunks(struct svcxprt_rdma *xprt,
- struct rpcrdma_write_array *wr_ary,
- struct rpcrdma_msg *rdma_resp,
- struct svc_rqst *rqstp,
- struct svc_rdma_req_map *vec)
+/* Load the xdr_buf into the ctxt's sge array, and DMA map each
+ * element as it is added.
+ *
+ * Returns the number of sge elements loaded on success, or
+ * a negative errno on failure.
+ */
+static int svc_rdma_map_reply_msg(struct svcxprt_rdma *rdma,
+ struct svc_rdma_op_ctxt *ctxt,
+ struct xdr_buf *xdr, __be32 *wr_lst)
{
- u32 xfer_len = rqstp->rq_res.page_len;
- int write_len;
- u32 xdr_off;
- int chunk_off;
- int chunk_no;
- int nchunks;
- struct rpcrdma_write_array *res_ary;
+ unsigned int len, sge_no, remaining, page_off;
+ struct page **ppages;
+ unsigned char *base;
+ u32 xdr_pad;
int ret;
- res_ary = (struct rpcrdma_write_array *)
- &rdma_resp->rm_body.rm_chunks[1];
-
- /* Write chunks start at the pagelist */
- nchunks = be32_to_cpu(wr_ary->wc_nchunks);
- for (xdr_off = rqstp->rq_res.head[0].iov_len, chunk_no = 0;
- xfer_len && chunk_no < nchunks;
- chunk_no++) {
- struct rpcrdma_segment *arg_ch;
- u64 rs_offset;
-
- arg_ch = &wr_ary->wc_array[chunk_no].wc_target;
- write_len = min(xfer_len, be32_to_cpu(arg_ch->rs_length));
-
- /* Prepare the response chunk given the length actually
- * written */
- xdr_decode_hyper((__be32 *)&arg_ch->rs_offset, &rs_offset);
- svc_rdma_xdr_encode_array_chunk(res_ary, chunk_no,
- arg_ch->rs_handle,
- arg_ch->rs_offset,
- write_len);
- chunk_off = 0;
- while (write_len) {
- ret = send_write(xprt, rqstp,
- be32_to_cpu(arg_ch->rs_handle),
- rs_offset + chunk_off,
- xdr_off,
- write_len,
- vec);
- if (ret <= 0)
- goto out_err;
- chunk_off += ret;
- xdr_off += ret;
- xfer_len -= ret;
- write_len -= ret;
+ sge_no = 1;
+
+ ret = svc_rdma_dma_map_buf(rdma, ctxt, sge_no++,
+ xdr->head[0].iov_base,
+ xdr->head[0].iov_len);
+ if (ret < 0)
+ return ret;
+
+ /* If a Write chunk is present, the xdr_buf's page list
+ * is not included inline. However the Upper Layer may
+ * have added XDR padding in the tail buffer, and that
+ * should not be included inline.
+ */
+ if (wr_lst) {
+ base = xdr->tail[0].iov_base;
+ len = xdr->tail[0].iov_len;
+ xdr_pad = xdr_padsize(xdr->page_len);
+
+ if (len && xdr_pad) {
+ base += xdr_pad;
+ len -= xdr_pad;
}
+
+ goto tail;
+ }
+
+ ppages = xdr->pages + (xdr->page_base >> PAGE_SHIFT);
+ page_off = xdr->page_base & ~PAGE_MASK;
+ remaining = xdr->page_len;
+ while (remaining) {
+ len = min_t(u32, PAGE_SIZE - page_off, remaining);
+
+ ret = svc_rdma_dma_map_page(rdma, ctxt, sge_no++,
+ *ppages++, page_off, len);
+ if (ret < 0)
+ return ret;
+
+ remaining -= len;
+ page_off = 0;
}
- /* Update the req with the number of chunks actually used */
- svc_rdma_xdr_encode_write_list(rdma_resp, chunk_no);
- return rqstp->rq_res.page_len;
+ base = xdr->tail[0].iov_base;
+ len = xdr->tail[0].iov_len;
+tail:
+ if (len) {
+ ret = svc_rdma_dma_map_buf(rdma, ctxt, sge_no++, base, len);
+ if (ret < 0)
+ return ret;
+ }
-out_err:
- pr_err("svcrdma: failed to send write chunks, rc=%d\n", ret);
- return -EIO;
+ return sge_no - 1;
}
-noinline
-static int send_reply_chunks(struct svcxprt_rdma *xprt,
- struct rpcrdma_write_array *rp_ary,
- struct rpcrdma_msg *rdma_resp,
- struct svc_rqst *rqstp,
- struct svc_rdma_req_map *vec)
+/* The svc_rqst and all resources it owns are released as soon as
+ * svc_rdma_sendto returns. Transfer pages under I/O to the ctxt
+ * so they are released by the Send completion handler.
+ */
+static void svc_rdma_save_io_pages(struct svc_rqst *rqstp,
+ struct svc_rdma_op_ctxt *ctxt)
{
- u32 xfer_len = rqstp->rq_res.len;
- int write_len;
- u32 xdr_off;
- int chunk_no;
- int chunk_off;
- int nchunks;
- struct rpcrdma_segment *ch;
- struct rpcrdma_write_array *res_ary;
- int ret;
+ int i, pages = rqstp->rq_next_page - rqstp->rq_respages;
- /* XXX: need to fix when reply lists occur with read-list and or
- * write-list */
- res_ary = (struct rpcrdma_write_array *)
- &rdma_resp->rm_body.rm_chunks[2];
-
- /* xdr offset starts at RPC message */
- nchunks = be32_to_cpu(rp_ary->wc_nchunks);
- for (xdr_off = 0, chunk_no = 0;
- xfer_len && chunk_no < nchunks;
- chunk_no++) {
- u64 rs_offset;
- ch = &rp_ary->wc_array[chunk_no].wc_target;
- write_len = min(xfer_len, be32_to_cpu(ch->rs_length));
-
- /* Prepare the reply chunk given the length actually
- * written */
- xdr_decode_hyper((__be32 *)&ch->rs_offset, &rs_offset);
- svc_rdma_xdr_encode_array_chunk(res_ary, chunk_no,
- ch->rs_handle, ch->rs_offset,
- write_len);
- chunk_off = 0;
- while (write_len) {
- ret = send_write(xprt, rqstp,
- be32_to_cpu(ch->rs_handle),
- rs_offset + chunk_off,
- xdr_off,
- write_len,
- vec);
- if (ret <= 0)
- goto out_err;
- chunk_off += ret;
- xdr_off += ret;
- xfer_len -= ret;
- write_len -= ret;
- }
+ ctxt->count += pages;
+ for (i = 0; i < pages; i++) {
+ ctxt->pages[i + 1] = rqstp->rq_respages[i];
+ rqstp->rq_respages[i] = NULL;
}
- /* Update the req with the number of chunks actually used */
- svc_rdma_xdr_encode_reply_array(res_ary, chunk_no);
+ rqstp->rq_next_page = rqstp->rq_respages + 1;
+}
- return rqstp->rq_res.len;
+/**
+ * svc_rdma_post_send_wr - Set up and post one Send Work Request
+ * @rdma: controlling transport
+ * @ctxt: op_ctxt for transmitting the Send WR
+ * @num_sge: number of SGEs to send
+ * @inv_rkey: R_key argument to Send With Invalidate, or zero
+ *
+ * Returns:
+ * %0 if the Send* was posted successfully,
+ * %-ENOTCONN if the connection was lost or dropped,
+ * %-EINVAL if there was a problem with the Send we built,
+ * %-ENOMEM if ib_post_send failed.
+ */
+int svc_rdma_post_send_wr(struct svcxprt_rdma *rdma,
+ struct svc_rdma_op_ctxt *ctxt, int num_sge,
+ u32 inv_rkey)
+{
+ struct ib_send_wr *send_wr = &ctxt->send_wr;
-out_err:
- pr_err("svcrdma: failed to send reply chunks, rc=%d\n", ret);
- return -EIO;
+ dprintk("svcrdma: posting Send WR with %u sge(s)\n", num_sge);
+
+ send_wr->next = NULL;
+ ctxt->cqe.done = svc_rdma_wc_send;
+ send_wr->wr_cqe = &ctxt->cqe;
+ send_wr->sg_list = ctxt->sge;
+ send_wr->num_sge = num_sge;
+ send_wr->send_flags = IB_SEND_SIGNALED;
+ if (inv_rkey) {
+ send_wr->opcode = IB_WR_SEND_WITH_INV;
+ send_wr->ex.invalidate_rkey = inv_rkey;
+ } else {
+ send_wr->opcode = IB_WR_SEND;
+ }
+
+ return svc_rdma_send(rdma, send_wr);
}
-/* This function prepares the portion of the RPCRDMA message to be
- * sent in the RDMA_SEND. This function is called after data sent via
- * RDMA has already been transmitted. There are three cases:
- * - The RPCRDMA header, RPC header, and payload are all sent in a
- * single RDMA_SEND. This is the "inline" case.
- * - The RPCRDMA header and some portion of the RPC header and data
- * are sent via this RDMA_SEND and another portion of the data is
- * sent via RDMA.
- * - The RPCRDMA header [NOMSG] is sent in this RDMA_SEND and the RPC
- * header and data are all transmitted via RDMA.
- * In all three cases, this function prepares the RPCRDMA header in
- * sge[0], the 'type' parameter indicates the type to place in the
- * RPCRDMA header, and the 'byte_count' field indicates how much of
- * the XDR to include in this RDMA_SEND. NB: The offset of the payload
- * to send is zero in the XDR.
+/* Prepare the portion of the RPC Reply that will be transmitted
+ * via RDMA Send. The RPC-over-RDMA transport header is prepared
+ * in sge[0], and the RPC xdr_buf is prepared in following sges.
+ *
+ * Depending on whether a Write list or Reply chunk is present,
+ * the server may send all, a portion of, or none of the xdr_buf.
+ * In the latter case, only the transport header (sge[0]) is
+ * transmitted.
+ *
+ * RDMA Send is the last step of transmitting an RPC reply. Pages
+ * involved in the earlier RDMA Writes are here transferred out
+ * of the rqstp and into the ctxt's page array. These pages are
+ * DMA unmapped by each Write completion, but the subsequent Send
+ * completion finally releases these pages.
+ *
+ * Assumptions:
+ * - The Reply's transport header will never be larger than a page.
*/
-static int send_reply(struct svcxprt_rdma *rdma,
- struct svc_rqst *rqstp,
- struct page *page,
- struct rpcrdma_msg *rdma_resp,
- struct svc_rdma_req_map *vec,
- int byte_count,
- u32 inv_rkey)
+static int svc_rdma_send_reply_msg(struct svcxprt_rdma *rdma,
+ __be32 *rdma_argp, __be32 *rdma_resp,
+ struct svc_rqst *rqstp,
+ __be32 *wr_lst, __be32 *rp_ch)
{
struct svc_rdma_op_ctxt *ctxt;
- struct ib_send_wr send_wr;
- u32 xdr_off;
- int sge_no;
- int sge_bytes;
- int page_no;
- int pages;
- int ret = -EIO;
-
- /* Prepare the context */
+ u32 inv_rkey;
+ int ret;
+
+ dprintk("svcrdma: sending %s reply: head=%zu, pagelen=%u, tail=%zu\n",
+ (rp_ch ? "RDMA_NOMSG" : "RDMA_MSG"),
+ rqstp->rq_res.head[0].iov_len,
+ rqstp->rq_res.page_len,
+ rqstp->rq_res.tail[0].iov_len);
+
ctxt = svc_rdma_get_context(rdma);
- ctxt->direction = DMA_TO_DEVICE;
- ctxt->pages[0] = page;
- ctxt->count = 1;
- /* Prepare the SGE for the RPCRDMA Header */
- ctxt->sge[0].lkey = rdma->sc_pd->local_dma_lkey;
- ctxt->sge[0].length =
- svc_rdma_xdr_get_reply_hdr_len((__be32 *)rdma_resp);
- ctxt->sge[0].addr =
- ib_dma_map_page(rdma->sc_cm_id->device, page, 0,
- ctxt->sge[0].length, DMA_TO_DEVICE);
- if (ib_dma_mapping_error(rdma->sc_cm_id->device, ctxt->sge[0].addr))
+ ret = svc_rdma_map_reply_hdr(rdma, ctxt, rdma_resp,
+ svc_rdma_reply_hdr_len(rdma_resp));
+ if (ret < 0)
goto err;
- svc_rdma_count_mappings(rdma, ctxt);
-
- ctxt->direction = DMA_TO_DEVICE;
- /* Map the payload indicated by 'byte_count' */
- xdr_off = 0;
- for (sge_no = 1; byte_count && sge_no < vec->count; sge_no++) {
- sge_bytes = min_t(size_t, vec->sge[sge_no].iov_len, byte_count);
- byte_count -= sge_bytes;
- ctxt->sge[sge_no].addr =
- dma_map_xdr(rdma, &rqstp->rq_res, xdr_off,
- sge_bytes, DMA_TO_DEVICE);
- xdr_off += sge_bytes;
- if (ib_dma_mapping_error(rdma->sc_cm_id->device,
- ctxt->sge[sge_no].addr))
+ if (!rp_ch) {
+ ret = svc_rdma_map_reply_msg(rdma, ctxt,
+ &rqstp->rq_res, wr_lst);
+ if (ret < 0)
goto err;
- svc_rdma_count_mappings(rdma, ctxt);
- ctxt->sge[sge_no].lkey = rdma->sc_pd->local_dma_lkey;
- ctxt->sge[sge_no].length = sge_bytes;
}
- if (byte_count != 0) {
- pr_err("svcrdma: Could not map %d bytes\n", byte_count);
+
+ svc_rdma_save_io_pages(rqstp, ctxt);
+
+ inv_rkey = 0;
+ if (rdma->sc_snd_w_inv)
+ inv_rkey = svc_rdma_get_inv_rkey(rdma_argp, wr_lst, rp_ch);
+ ret = svc_rdma_post_send_wr(rdma, ctxt, 1 + ret, inv_rkey);
+ if (ret)
goto err;
- }
- /* Save all respages in the ctxt and remove them from the
- * respages array. They are our pages until the I/O
- * completes.
+ return 0;
+
+err:
+ pr_err("svcrdma: failed to post Send WR (%d)\n", ret);
+ svc_rdma_unmap_dma(ctxt);
+ svc_rdma_put_context(ctxt, 1);
+ return ret;
+}
+
+/* Given the client-provided Write and Reply chunks, the server was not
+ * able to form a complete reply. Return an RDMA_ERROR message so the
+ * client can retire this RPC transaction. As above, the Send completion
+ * routine releases payload pages that were part of a previous RDMA Write.
+ *
+ * Remote Invalidation is skipped for simplicity.
+ */
+static int svc_rdma_send_error_msg(struct svcxprt_rdma *rdma,
+ __be32 *rdma_resp, struct svc_rqst *rqstp)
+{
+ struct svc_rdma_op_ctxt *ctxt;
+ __be32 *p;
+ int ret;
+
+ ctxt = svc_rdma_get_context(rdma);
+
+ /* Replace the original transport header with an
+ * RDMA_ERROR response. XID etc are preserved.
*/
- pages = rqstp->rq_next_page - rqstp->rq_respages;
- for (page_no = 0; page_no < pages; page_no++) {
- ctxt->pages[page_no+1] = rqstp->rq_respages[page_no];
- ctxt->count++;
- rqstp->rq_respages[page_no] = NULL;
- }
- rqstp->rq_next_page = rqstp->rq_respages + 1;
+ p = rdma_resp + 3;
+ *p++ = rdma_error;
+ *p = err_chunk;
- if (sge_no > rdma->sc_max_sge) {
- pr_err("svcrdma: Too many sges (%d)\n", sge_no);
+ ret = svc_rdma_map_reply_hdr(rdma, ctxt, rdma_resp, 20);
+ if (ret < 0)
goto err;
- }
- memset(&send_wr, 0, sizeof send_wr);
- ctxt->cqe.done = svc_rdma_wc_send;
- send_wr.wr_cqe = &ctxt->cqe;
- send_wr.sg_list = ctxt->sge;
- send_wr.num_sge = sge_no;
- if (inv_rkey) {
- send_wr.opcode = IB_WR_SEND_WITH_INV;
- send_wr.ex.invalidate_rkey = inv_rkey;
- } else
- send_wr.opcode = IB_WR_SEND;
- send_wr.send_flags = IB_SEND_SIGNALED;
- ret = svc_rdma_send(rdma, &send_wr);
+ svc_rdma_save_io_pages(rqstp, ctxt);
+
+ ret = svc_rdma_post_send_wr(rdma, ctxt, 1 + ret, 0);
if (ret)
goto err;
return 0;
- err:
+err:
+ pr_err("svcrdma: failed to post Send WR (%d)\n", ret);
svc_rdma_unmap_dma(ctxt);
svc_rdma_put_context(ctxt, 1);
return ret;
@@ -552,39 +599,36 @@ void svc_rdma_prep_reply_hdr(struct svc_rqst *rqstp)
{
}
+/**
+ * svc_rdma_sendto - Transmit an RPC reply
+ * @rqstp: processed RPC request, reply XDR already in ::rq_res
+ *
+ * Any resources still associated with @rqstp are released upon return.
+ * If no reply message was possible, the connection is closed.
+ *
+ * Returns:
+ * %0 if an RPC reply has been successfully posted,
+ * %-ENOMEM if a resource shortage occurred (connection is lost),
+ * %-ENOTCONN if posting failed (connection is lost).
+ */
int svc_rdma_sendto(struct svc_rqst *rqstp)
{
struct svc_xprt *xprt = rqstp->rq_xprt;
struct svcxprt_rdma *rdma =
container_of(xprt, struct svcxprt_rdma, sc_xprt);
- struct rpcrdma_msg *rdma_argp;
- struct rpcrdma_msg *rdma_resp;
- struct rpcrdma_write_array *wr_ary, *rp_ary;
- int ret;
- int inline_bytes;
+ __be32 *p, *rdma_argp, *rdma_resp, *wr_lst, *rp_ch;
+ struct xdr_buf *xdr = &rqstp->rq_res;
struct page *res_page;
- struct svc_rdma_req_map *vec;
- u32 inv_rkey;
- __be32 *p;
-
- dprintk("svcrdma: sending response for rqstp=%p\n", rqstp);
+ int ret;
- /* Get the RDMA request header. The receive logic always
- * places this at the start of page 0.
+ /* Find the call's chunk lists to decide how to send the reply.
+ * Receive places the Call's xprt header at the start of page 0.
*/
rdma_argp = page_address(rqstp->rq_pages[0]);
- svc_rdma_get_write_arrays(rdma_argp, &wr_ary, &rp_ary);
-
- inv_rkey = 0;
- if (rdma->sc_snd_w_inv)
- inv_rkey = svc_rdma_get_inv_rkey(rdma_argp, wr_ary, rp_ary);
+ svc_rdma_get_write_arrays(rdma_argp, &wr_lst, &rp_ch);
- /* Build an req vec for the XDR */
- vec = svc_rdma_get_req_map(rdma);
- ret = svc_rdma_map_xdr(rdma, &rqstp->rq_res, vec, wr_ary != NULL);
- if (ret)
- goto err0;
- inline_bytes = rqstp->rq_res.len;
+ dprintk("svcrdma: preparing response for XID 0x%08x\n",
+ be32_to_cpup(rdma_argp));
/* Create the RDMA response header. xprt->xpt_mutex,
* acquired in svc_send(), serializes RPC replies. The
@@ -598,115 +642,57 @@ int svc_rdma_sendto(struct svc_rqst *rqstp)
goto err0;
rdma_resp = page_address(res_page);
- p = &rdma_resp->rm_xid;
- *p++ = rdma_argp->rm_xid;
- *p++ = rdma_argp->rm_vers;
+ p = rdma_resp;
+ *p++ = *rdma_argp;
+ *p++ = *(rdma_argp + 1);
*p++ = rdma->sc_fc_credits;
- *p++ = rp_ary ? rdma_nomsg : rdma_msg;
+ *p++ = rp_ch ? rdma_nomsg : rdma_msg;
/* Start with empty chunks */
*p++ = xdr_zero;
*p++ = xdr_zero;
*p = xdr_zero;
- /* Send any write-chunk data and build resp write-list */
- if (wr_ary) {
- ret = send_write_chunks(rdma, wr_ary, rdma_resp, rqstp, vec);
+ if (wr_lst) {
+ /* XXX: Presume the client sent only one Write chunk */
+ ret = svc_rdma_send_write_chunk(rdma, wr_lst, xdr);
if (ret < 0)
- goto err1;
- inline_bytes -= ret + xdr_padsize(ret);
+ goto err2;
+ svc_rdma_xdr_encode_write_list(rdma_resp, wr_lst, ret);
}
-
- /* Send any reply-list data and update resp reply-list */
- if (rp_ary) {
- ret = send_reply_chunks(rdma, rp_ary, rdma_resp, rqstp, vec);
+ if (rp_ch) {
+ ret = svc_rdma_send_reply_chunk(rdma, rp_ch, wr_lst, xdr);
if (ret < 0)
- goto err1;
- inline_bytes -= ret;
+ goto err2;
+ svc_rdma_xdr_encode_reply_chunk(rdma_resp, rp_ch, ret);
}
- /* Post a fresh Receive buffer _before_ sending the reply */
ret = svc_rdma_post_recv(rdma, GFP_KERNEL);
if (ret)
goto err1;
-
- ret = send_reply(rdma, rqstp, res_page, rdma_resp, vec,
- inline_bytes, inv_rkey);
+ ret = svc_rdma_send_reply_msg(rdma, rdma_argp, rdma_resp, rqstp,
+ wr_lst, rp_ch);
if (ret < 0)
goto err0;
+ return 0;
- svc_rdma_put_req_map(rdma, vec);
- dprintk("svcrdma: send_reply returns %d\n", ret);
- return ret;
+ err2:
+ if (ret != -E2BIG)
+ goto err1;
+
+ ret = svc_rdma_post_recv(rdma, GFP_KERNEL);
+ if (ret)
+ goto err1;
+ ret = svc_rdma_send_error_msg(rdma, rdma_resp, rqstp);
+ if (ret < 0)
+ goto err0;
+ return 0;
err1:
put_page(res_page);
err0:
- svc_rdma_put_req_map(rdma, vec);
pr_err("svcrdma: Could not send reply, err=%d. Closing transport.\n",
ret);
- set_bit(XPT_CLOSE, &rdma->sc_xprt.xpt_flags);
+ set_bit(XPT_CLOSE, &xprt->xpt_flags);
return -ENOTCONN;
}
-
-void svc_rdma_send_error(struct svcxprt_rdma *xprt, struct rpcrdma_msg *rmsgp,
- int status)
-{
- struct ib_send_wr err_wr;
- struct page *p;
- struct svc_rdma_op_ctxt *ctxt;
- enum rpcrdma_errcode err;
- __be32 *va;
- int length;
- int ret;
-
- ret = svc_rdma_repost_recv(xprt, GFP_KERNEL);
- if (ret)
- return;
-
- p = alloc_page(GFP_KERNEL);
- if (!p)
- return;
- va = page_address(p);
-
- /* XDR encode an error reply */
- err = ERR_CHUNK;
- if (status == -EPROTONOSUPPORT)
- err = ERR_VERS;
- length = svc_rdma_xdr_encode_error(xprt, rmsgp, err, va);
-
- ctxt = svc_rdma_get_context(xprt);
- ctxt->direction = DMA_TO_DEVICE;
- ctxt->count = 1;
- ctxt->pages[0] = p;
-
- /* Prepare SGE for local address */
- ctxt->sge[0].lkey = xprt->sc_pd->local_dma_lkey;
- ctxt->sge[0].length = length;
- ctxt->sge[0].addr = ib_dma_map_page(xprt->sc_cm_id->device,
- p, 0, length, DMA_TO_DEVICE);
- if (ib_dma_mapping_error(xprt->sc_cm_id->device, ctxt->sge[0].addr)) {
- dprintk("svcrdma: Error mapping buffer for protocol error\n");
- svc_rdma_put_context(ctxt, 1);
- return;
- }
- svc_rdma_count_mappings(xprt, ctxt);
-
- /* Prepare SEND WR */
- memset(&err_wr, 0, sizeof(err_wr));
- ctxt->cqe.done = svc_rdma_wc_send;
- err_wr.wr_cqe = &ctxt->cqe;
- err_wr.sg_list = ctxt->sge;
- err_wr.num_sge = 1;
- err_wr.opcode = IB_WR_SEND;
- err_wr.send_flags = IB_SEND_SIGNALED;
-
- /* Post It */
- ret = svc_rdma_send(xprt, &err_wr);
- if (ret) {
- dprintk("svcrdma: Error %d posting send for protocol error\n",
- ret);
- svc_rdma_unmap_dma(ctxt);
- svc_rdma_put_context(ctxt, 1);
- }
-}
diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c
index fc8f14c7bfec..a9d9cb1ba4c6 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_transport.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c
@@ -272,85 +272,6 @@ static void svc_rdma_destroy_ctxts(struct svcxprt_rdma *xprt)
}
}
-static struct svc_rdma_req_map *alloc_req_map(gfp_t flags)
-{
- struct svc_rdma_req_map *map;
-
- map = kmalloc(sizeof(*map), flags);
- if (map)
- INIT_LIST_HEAD(&map->free);
- return map;
-}
-
-static bool svc_rdma_prealloc_maps(struct svcxprt_rdma *xprt)
-{
- unsigned int i;
-
- /* One for each receive buffer on this connection. */
- i = xprt->sc_max_requests;
-
- while (i--) {
- struct svc_rdma_req_map *map;
-
- map = alloc_req_map(GFP_KERNEL);
- if (!map) {
- dprintk("svcrdma: No memory for request map\n");
- return false;
- }
- list_add(&map->free, &xprt->sc_maps);
- }
- return true;
-}
-
-struct svc_rdma_req_map *svc_rdma_get_req_map(struct svcxprt_rdma *xprt)
-{
- struct svc_rdma_req_map *map = NULL;
-
- spin_lock(&xprt->sc_map_lock);
- if (list_empty(&xprt->sc_maps))
- goto out_empty;
-
- map = list_first_entry(&xprt->sc_maps,
- struct svc_rdma_req_map, free);
- list_del_init(&map->free);
- spin_unlock(&xprt->sc_map_lock);
-
-out:
- map->count = 0;
- return map;
-
-out_empty:
- spin_unlock(&xprt->sc_map_lock);
-
- /* Pre-allocation amount was incorrect */
- map = alloc_req_map(GFP_NOIO);
- if (map)
- goto out;
-
- WARN_ONCE(1, "svcrdma: empty request map list?\n");
- return NULL;
-}
-
-void svc_rdma_put_req_map(struct svcxprt_rdma *xprt,
- struct svc_rdma_req_map *map)
-{
- spin_lock(&xprt->sc_map_lock);
- list_add(&map->free, &xprt->sc_maps);
- spin_unlock(&xprt->sc_map_lock);
-}
-
-static void svc_rdma_destroy_maps(struct svcxprt_rdma *xprt)
-{
- while (!list_empty(&xprt->sc_maps)) {
- struct svc_rdma_req_map *map;
-
- map = list_first_entry(&xprt->sc_maps,
- struct svc_rdma_req_map, free);
- list_del(&map->free);
- kfree(map);
- }
-}
-
/* QP event handler */
static void qp_event_handler(struct ib_event *event, void *context)
{
@@ -474,24 +395,6 @@ void svc_rdma_wc_send(struct ib_cq *cq, struct ib_wc *wc)
}
/**
- * svc_rdma_wc_write - Invoked by RDMA provider for each polled Write WC
- * @cq: completion queue
- * @wc: completed WR
- *
- */
-void svc_rdma_wc_write(struct ib_cq *cq, struct ib_wc *wc)
-{
- struct ib_cqe *cqe = wc->wr_cqe;
- struct svc_rdma_op_ctxt *ctxt;
-
- svc_rdma_send_wc_common_put(cq, wc, "write");
-
- ctxt = container_of(cqe, struct svc_rdma_op_ctxt, cqe);
- svc_rdma_unmap_dma(ctxt);
- svc_rdma_put_context(ctxt, 0);
-}
-
-/**
* svc_rdma_wc_reg - Invoked by RDMA provider for each polled FASTREG WC
* @cq: completion queue
* @wc: completed WR
@@ -561,14 +464,14 @@ static struct svcxprt_rdma *rdma_create_xprt(struct svc_serv *serv,
INIT_LIST_HEAD(&cma_xprt->sc_read_complete_q);
INIT_LIST_HEAD(&cma_xprt->sc_frmr_q);
INIT_LIST_HEAD(&cma_xprt->sc_ctxts);
- INIT_LIST_HEAD(&cma_xprt->sc_maps);
+ INIT_LIST_HEAD(&cma_xprt->sc_rw_ctxts);
init_waitqueue_head(&cma_xprt->sc_send_wait);
spin_lock_init(&cma_xprt->sc_lock);
spin_lock_init(&cma_xprt->sc_rq_dto_lock);
spin_lock_init(&cma_xprt->sc_frmr_q_lock);
spin_lock_init(&cma_xprt->sc_ctxt_lock);
- spin_lock_init(&cma_xprt->sc_map_lock);
+ spin_lock_init(&cma_xprt->sc_rw_ctxt_lock);
/*
* Note that this implies that the underlying transport support
@@ -999,6 +902,7 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt)
newxprt, newxprt->sc_cm_id);
dev = newxprt->sc_cm_id->device;
+ newxprt->sc_port_num = newxprt->sc_cm_id->port_num;
/* Qualify the transport resource defaults with the
* capabilities of this particular device */
@@ -1014,13 +918,11 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt)
svcrdma_max_bc_requests);
newxprt->sc_rq_depth = newxprt->sc_max_requests +
newxprt->sc_max_bc_requests;
- newxprt->sc_sq_depth = RPCRDMA_SQ_DEPTH_MULT * newxprt->sc_rq_depth;
+ newxprt->sc_sq_depth = newxprt->sc_rq_depth;
atomic_set(&newxprt->sc_sq_avail, newxprt->sc_sq_depth);
if (!svc_rdma_prealloc_ctxts(newxprt))
goto errout;
- if (!svc_rdma_prealloc_maps(newxprt))
- goto errout;
/*
* Limit ORD based on client limit, local device limit, and
@@ -1050,6 +952,8 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt)
memset(&qp_attr, 0, sizeof qp_attr);
qp_attr.event_handler = qp_event_handler;
qp_attr.qp_context = &newxprt->sc_xprt;
+ qp_attr.port_num = newxprt->sc_cm_id->port_num;
+ qp_attr.cap.max_rdma_ctxs = newxprt->sc_max_requests;
qp_attr.cap.max_send_wr = newxprt->sc_sq_depth;
qp_attr.cap.max_recv_wr = newxprt->sc_rq_depth;
qp_attr.cap.max_send_sge = newxprt->sc_max_sge;
@@ -1248,8 +1152,8 @@ static void __svc_rdma_free(struct work_struct *work)
}
rdma_dealloc_frmr_q(rdma);
+ svc_rdma_destroy_rw_ctxts(rdma);
svc_rdma_destroy_ctxts(rdma);
- svc_rdma_destroy_maps(rdma);
/* Destroy the QP if present (not a listener) */
if (rdma->sc_qp && !IS_ERR(rdma->sc_qp))