RPC/RDMA: refactor the inline memory registration code.
authorTom Talpey <talpey@netapp.com>
Thu, 9 Oct 2008 18:59:49 +0000 (14:59 -0400)
committerTrond Myklebust <Trond.Myklebust@netapp.com>
Fri, 10 Oct 2008 19:09:16 +0000 (15:09 -0400)
Refactor the memory registration and deregistration routines.
This saves stack space, makes the code more readable and prepares
to add the new FRMR registration methods.

Signed-off-by: Tom Talpey <talpey@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
net/sunrpc/xprtrdma/verbs.c

index 8ea283e..d04208a 100644 (file)
@@ -863,6 +863,7 @@ rpcrdma_buffer_create(struct rpcrdma_buffer *buf, struct rpcrdma_ep *ep,
        char *p;
        size_t len;
        int i, rc;
+       struct rpcrdma_mw *r;
 
        buf->rb_max_requests = cdata->max_requests;
        spin_lock_init(&buf->rb_lock);
@@ -873,7 +874,7 @@ rpcrdma_buffer_create(struct rpcrdma_buffer *buf, struct rpcrdma_ep *ep,
         *   2.  arrays of struct rpcrdma_req to fill in pointers
         *   3.  array of struct rpcrdma_rep for replies
         *   4.  padding, if any
-        *   5.  mw's, if any
+        *   5.  mw's or fmr's, if any
         * Send/recv buffers in req/rep need to be registered
         */
 
@@ -927,15 +928,13 @@ rpcrdma_buffer_create(struct rpcrdma_buffer *buf, struct rpcrdma_ep *ep,
         * and also reduce unbind-to-bind collision.
         */
        INIT_LIST_HEAD(&buf->rb_mws);
+       r = (struct rpcrdma_mw *)p;
        switch (ia->ri_memreg_strategy) {
        case RPCRDMA_MTHCAFMR:
-               {
-               struct rpcrdma_mw *r = (struct rpcrdma_mw *)p;
-               struct ib_fmr_attr fa = {
-                       RPCRDMA_MAX_DATA_SEGS, 1, PAGE_SHIFT
-               };
                /* TBD we are perhaps overallocating here */
                for (i = (buf->rb_max_requests+1) * RPCRDMA_MAX_SEGS; i; i--) {
+                       static struct ib_fmr_attr fa =
+                               { RPCRDMA_MAX_DATA_SEGS, 1, PAGE_SHIFT };
                        r->r.fmr = ib_alloc_fmr(ia->ri_pd,
                                IB_ACCESS_REMOTE_WRITE | IB_ACCESS_REMOTE_READ,
                                &fa);
@@ -948,12 +947,9 @@ rpcrdma_buffer_create(struct rpcrdma_buffer *buf, struct rpcrdma_ep *ep,
                        list_add(&r->mw_list, &buf->rb_mws);
                        ++r;
                }
-               }
                break;
        case RPCRDMA_MEMWINDOWS_ASYNC:
        case RPCRDMA_MEMWINDOWS:
-               {
-               struct rpcrdma_mw *r = (struct rpcrdma_mw *)p;
                /* Allocate one extra request's worth, for full cycling */
                for (i = (buf->rb_max_requests+1) * RPCRDMA_MAX_SEGS; i; i--) {
                        r->r.mw = ib_alloc_mw(ia->ri_pd);
@@ -966,7 +962,6 @@ rpcrdma_buffer_create(struct rpcrdma_buffer *buf, struct rpcrdma_ep *ep,
                        list_add(&r->mw_list, &buf->rb_mws);
                        ++r;
                }
-               }
                break;
        default:
                break;
@@ -1046,6 +1041,7 @@ rpcrdma_buffer_destroy(struct rpcrdma_buffer *buf)
 {
        int rc, i;
        struct rpcrdma_ia *ia = rdmab_to_ia(buf);
+       struct rpcrdma_mw *r;
 
        /* clean up in reverse order from create
         *   1.  recv mr memory (mr free, then kfree)
@@ -1065,7 +1061,6 @@ rpcrdma_buffer_destroy(struct rpcrdma_buffer *buf)
                }
                if (buf->rb_send_bufs && buf->rb_send_bufs[i]) {
                        while (!list_empty(&buf->rb_mws)) {
-                               struct rpcrdma_mw *r;
                                r = list_entry(buf->rb_mws.next,
                                        struct rpcrdma_mw, mw_list);
                                list_del(&r->mw_list);
@@ -1115,6 +1110,8 @@ rpcrdma_buffer_get(struct rpcrdma_buffer *buffers)
 {
        struct rpcrdma_req *req;
        unsigned long flags;
+       int i;
+       struct rpcrdma_mw *r;
 
        spin_lock_irqsave(&buffers->rb_lock, flags);
        if (buffers->rb_send_index == buffers->rb_max_requests) {
@@ -1135,9 +1132,8 @@ rpcrdma_buffer_get(struct rpcrdma_buffer *buffers)
        }
        buffers->rb_send_bufs[buffers->rb_send_index++] = NULL;
        if (!list_empty(&buffers->rb_mws)) {
-               int i = RPCRDMA_MAX_SEGS - 1;
+               i = RPCRDMA_MAX_SEGS - 1;
                do {
-                       struct rpcrdma_mw *r;
                        r = list_entry(buffers->rb_mws.next,
                                        struct rpcrdma_mw, mw_list);
                        list_del(&r->mw_list);
@@ -1329,15 +1325,202 @@ rpcrdma_unmap_one(struct rpcrdma_ia *ia, struct rpcrdma_mr_seg *seg)
                                seg->mr_dma, seg->mr_dmalen, seg->mr_dir);
 }
 
+static int
+rpcrdma_register_fmr_external(struct rpcrdma_mr_seg *seg,
+                       int *nsegs, int writing, struct rpcrdma_ia *ia)
+{
+       struct rpcrdma_mr_seg *seg1 = seg;
+       u64 physaddrs[RPCRDMA_MAX_DATA_SEGS];
+       int len, pageoff, i, rc;
+
+       pageoff = offset_in_page(seg1->mr_offset);
+       seg1->mr_offset -= pageoff;     /* start of page */
+       seg1->mr_len += pageoff;
+       len = -pageoff;
+       if (*nsegs > RPCRDMA_MAX_DATA_SEGS)
+               *nsegs = RPCRDMA_MAX_DATA_SEGS;
+       for (i = 0; i < *nsegs;) {
+               rpcrdma_map_one(ia, seg, writing);
+               physaddrs[i] = seg->mr_dma;
+               len += seg->mr_len;
+               ++seg;
+               ++i;
+               /* Check for holes */
+               if ((i < *nsegs && offset_in_page(seg->mr_offset)) ||
+                   offset_in_page((seg-1)->mr_offset + (seg-1)->mr_len))
+                       break;
+       }
+       rc = ib_map_phys_fmr(seg1->mr_chunk.rl_mw->r.fmr,
+                               physaddrs, i, seg1->mr_dma);
+       if (rc) {
+               dprintk("RPC:       %s: failed ib_map_phys_fmr "
+                       "%u@0x%llx+%i (%d)... status %i\n", __func__,
+                       len, (unsigned long long)seg1->mr_dma,
+                       pageoff, i, rc);
+               while (i--)
+                       rpcrdma_unmap_one(ia, --seg);
+       } else {
+               seg1->mr_rkey = seg1->mr_chunk.rl_mw->r.fmr->rkey;
+               seg1->mr_base = seg1->mr_dma + pageoff;
+               seg1->mr_nsegs = i;
+               seg1->mr_len = len;
+       }
+       *nsegs = i;
+       return rc;
+}
+
+static int
+rpcrdma_deregister_fmr_external(struct rpcrdma_mr_seg *seg,
+                       struct rpcrdma_ia *ia)
+{
+       struct rpcrdma_mr_seg *seg1 = seg;
+       LIST_HEAD(l);
+       int rc;
+
+       list_add(&seg1->mr_chunk.rl_mw->r.fmr->list, &l);
+       rc = ib_unmap_fmr(&l);
+       while (seg1->mr_nsegs--)
+               rpcrdma_unmap_one(ia, seg++);
+       if (rc)
+               dprintk("RPC:       %s: failed ib_unmap_fmr,"
+                       " status %i\n", __func__, rc);
+       return rc;
+}
+
+static int
+rpcrdma_register_memwin_external(struct rpcrdma_mr_seg *seg,
+                       int *nsegs, int writing, struct rpcrdma_ia *ia,
+                       struct rpcrdma_xprt *r_xprt)
+{
+       int mem_priv = (writing ? IB_ACCESS_REMOTE_WRITE :
+                                 IB_ACCESS_REMOTE_READ);
+       struct ib_mw_bind param;
+       int rc;
+
+       *nsegs = 1;
+       rpcrdma_map_one(ia, seg, writing);
+       param.mr = ia->ri_bind_mem;
+       param.wr_id = 0ULL;     /* no send cookie */
+       param.addr = seg->mr_dma;
+       param.length = seg->mr_len;
+       param.send_flags = 0;
+       param.mw_access_flags = mem_priv;
+
+       DECR_CQCOUNT(&r_xprt->rx_ep);
+       rc = ib_bind_mw(ia->ri_id->qp, seg->mr_chunk.rl_mw->r.mw, &param);
+       if (rc) {
+               dprintk("RPC:       %s: failed ib_bind_mw "
+                       "%u@0x%llx status %i\n",
+                       __func__, seg->mr_len,
+                       (unsigned long long)seg->mr_dma, rc);
+               rpcrdma_unmap_one(ia, seg);
+       } else {
+               seg->mr_rkey = seg->mr_chunk.rl_mw->r.mw->rkey;
+               seg->mr_base = param.addr;
+               seg->mr_nsegs = 1;
+       }
+       return rc;
+}
+
+static int
+rpcrdma_deregister_memwin_external(struct rpcrdma_mr_seg *seg,
+                       struct rpcrdma_ia *ia,
+                       struct rpcrdma_xprt *r_xprt, void **r)
+{
+       struct ib_mw_bind param;
+       LIST_HEAD(l);
+       int rc;
+
+       BUG_ON(seg->mr_nsegs != 1);
+       param.mr = ia->ri_bind_mem;
+       param.addr = 0ULL;      /* unbind */
+       param.length = 0;
+       param.mw_access_flags = 0;
+       if (*r) {
+               param.wr_id = (u64) (unsigned long) *r;
+               param.send_flags = IB_SEND_SIGNALED;
+               INIT_CQCOUNT(&r_xprt->rx_ep);
+       } else {
+               param.wr_id = 0ULL;
+               param.send_flags = 0;
+               DECR_CQCOUNT(&r_xprt->rx_ep);
+       }
+       rc = ib_bind_mw(ia->ri_id->qp, seg->mr_chunk.rl_mw->r.mw, &param);
+       rpcrdma_unmap_one(ia, seg);
+       if (rc)
+               dprintk("RPC:       %s: failed ib_(un)bind_mw,"
+                       " status %i\n", __func__, rc);
+       else
+               *r = NULL;      /* will upcall on completion */
+       return rc;
+}
+
+static int
+rpcrdma_register_default_external(struct rpcrdma_mr_seg *seg,
+                       int *nsegs, int writing, struct rpcrdma_ia *ia)
+{
+       int mem_priv = (writing ? IB_ACCESS_REMOTE_WRITE :
+                                 IB_ACCESS_REMOTE_READ);
+       struct rpcrdma_mr_seg *seg1 = seg;
+       struct ib_phys_buf ipb[RPCRDMA_MAX_DATA_SEGS];
+       int len, i, rc = 0;
+
+       if (*nsegs > RPCRDMA_MAX_DATA_SEGS)
+               *nsegs = RPCRDMA_MAX_DATA_SEGS;
+       for (len = 0, i = 0; i < *nsegs;) {
+               rpcrdma_map_one(ia, seg, writing);
+               ipb[i].addr = seg->mr_dma;
+               ipb[i].size = seg->mr_len;
+               len += seg->mr_len;
+               ++seg;
+               ++i;
+               /* Check for holes */
+               if ((i < *nsegs && offset_in_page(seg->mr_offset)) ||
+                   offset_in_page((seg-1)->mr_offset+(seg-1)->mr_len))
+                       break;
+       }
+       seg1->mr_base = seg1->mr_dma;
+       seg1->mr_chunk.rl_mr = ib_reg_phys_mr(ia->ri_pd,
+                               ipb, i, mem_priv, &seg1->mr_base);
+       if (IS_ERR(seg1->mr_chunk.rl_mr)) {
+               rc = PTR_ERR(seg1->mr_chunk.rl_mr);
+               dprintk("RPC:       %s: failed ib_reg_phys_mr "
+                       "%u@0x%llx (%d)... status %i\n",
+                       __func__, len,
+                       (unsigned long long)seg1->mr_dma, i, rc);
+               while (i--)
+                       rpcrdma_unmap_one(ia, --seg);
+       } else {
+               seg1->mr_rkey = seg1->mr_chunk.rl_mr->rkey;
+               seg1->mr_nsegs = i;
+               seg1->mr_len = len;
+       }
+       *nsegs = i;
+       return rc;
+}
+
+static int
+rpcrdma_deregister_default_external(struct rpcrdma_mr_seg *seg,
+                       struct rpcrdma_ia *ia)
+{
+       struct rpcrdma_mr_seg *seg1 = seg;
+       int rc;
+
+       rc = ib_dereg_mr(seg1->mr_chunk.rl_mr);
+       seg1->mr_chunk.rl_mr = NULL;
+       while (seg1->mr_nsegs--)
+               rpcrdma_unmap_one(ia, seg++);
+       if (rc)
+               dprintk("RPC:       %s: failed ib_dereg_mr,"
+                       " status %i\n", __func__, rc);
+       return rc;
+}
+
 int
 rpcrdma_register_external(struct rpcrdma_mr_seg *seg,
                        int nsegs, int writing, struct rpcrdma_xprt *r_xprt)
 {
        struct rpcrdma_ia *ia = &r_xprt->rx_ia;
-       int mem_priv = (writing ? IB_ACCESS_REMOTE_WRITE :
-                                 IB_ACCESS_REMOTE_READ);
-       struct rpcrdma_mr_seg *seg1 = seg;
-       int i;
        int rc = 0;
 
        switch (ia->ri_memreg_strategy) {
@@ -1352,114 +1535,20 @@ rpcrdma_register_external(struct rpcrdma_mr_seg *seg,
                break;
 #endif
 
-       /* Registration using fast memory registration */
+       /* Registration using fmr memory registration */
        case RPCRDMA_MTHCAFMR:
-               {
-               u64 physaddrs[RPCRDMA_MAX_DATA_SEGS];
-               int len, pageoff = offset_in_page(seg->mr_offset);
-               seg1->mr_offset -= pageoff;     /* start of page */
-               seg1->mr_len += pageoff;
-               len = -pageoff;
-               if (nsegs > RPCRDMA_MAX_DATA_SEGS)
-                       nsegs = RPCRDMA_MAX_DATA_SEGS;
-               for (i = 0; i < nsegs;) {
-                       rpcrdma_map_one(ia, seg, writing);
-                       physaddrs[i] = seg->mr_dma;
-                       len += seg->mr_len;
-                       ++seg;
-                       ++i;
-                       /* Check for holes */
-                       if ((i < nsegs && offset_in_page(seg->mr_offset)) ||
-                           offset_in_page((seg-1)->mr_offset+(seg-1)->mr_len))
-                               break;
-               }
-               nsegs = i;
-               rc = ib_map_phys_fmr(seg1->mr_chunk.rl_mw->r.fmr,
-                                       physaddrs, nsegs, seg1->mr_dma);
-               if (rc) {
-                       dprintk("RPC:       %s: failed ib_map_phys_fmr "
-                               "%u@0x%llx+%i (%d)... status %i\n", __func__,
-                               len, (unsigned long long)seg1->mr_dma,
-                               pageoff, nsegs, rc);
-                       while (nsegs--)
-                               rpcrdma_unmap_one(ia, --seg);
-               } else {
-                       seg1->mr_rkey = seg1->mr_chunk.rl_mw->r.fmr->rkey;
-                       seg1->mr_base = seg1->mr_dma + pageoff;
-                       seg1->mr_nsegs = nsegs;
-                       seg1->mr_len = len;
-               }
-               }
+               rc = rpcrdma_register_fmr_external(seg, &nsegs, writing, ia);
                break;
 
        /* Registration using memory windows */
        case RPCRDMA_MEMWINDOWS_ASYNC:
        case RPCRDMA_MEMWINDOWS:
-               {
-               struct ib_mw_bind param;
-               rpcrdma_map_one(ia, seg, writing);
-               param.mr = ia->ri_bind_mem;
-               param.wr_id = 0ULL;     /* no send cookie */
-               param.addr = seg->mr_dma;
-               param.length = seg->mr_len;
-               param.send_flags = 0;
-               param.mw_access_flags = mem_priv;
-
-               DECR_CQCOUNT(&r_xprt->rx_ep);
-               rc = ib_bind_mw(ia->ri_id->qp,
-                                       seg->mr_chunk.rl_mw->r.mw, &param);
-               if (rc) {
-                       dprintk("RPC:       %s: failed ib_bind_mw "
-                               "%u@0x%llx status %i\n",
-                               __func__, seg->mr_len,
-                               (unsigned long long)seg->mr_dma, rc);
-                       rpcrdma_unmap_one(ia, seg);
-               } else {
-                       seg->mr_rkey = seg->mr_chunk.rl_mw->r.mw->rkey;
-                       seg->mr_base = param.addr;
-                       seg->mr_nsegs = 1;
-                       nsegs = 1;
-               }
-               }
+               rc = rpcrdma_register_memwin_external(seg, &nsegs, writing, ia, r_xprt);
                break;
 
        /* Default registration each time */
        default:
-               {
-               struct ib_phys_buf ipb[RPCRDMA_MAX_DATA_SEGS];
-               int len = 0;
-               if (nsegs > RPCRDMA_MAX_DATA_SEGS)
-                       nsegs = RPCRDMA_MAX_DATA_SEGS;
-               for (i = 0; i < nsegs;) {
-                       rpcrdma_map_one(ia, seg, writing);
-                       ipb[i].addr = seg->mr_dma;
-                       ipb[i].size = seg->mr_len;
-                       len += seg->mr_len;
-                       ++seg;
-                       ++i;
-                       /* Check for holes */
-                       if ((i < nsegs && offset_in_page(seg->mr_offset)) ||
-                           offset_in_page((seg-1)->mr_offset+(seg-1)->mr_len))
-                               break;
-               }
-               nsegs = i;
-               seg1->mr_base = seg1->mr_dma;
-               seg1->mr_chunk.rl_mr = ib_reg_phys_mr(ia->ri_pd,
-                                       ipb, nsegs, mem_priv, &seg1->mr_base);
-               if (IS_ERR(seg1->mr_chunk.rl_mr)) {
-                       rc = PTR_ERR(seg1->mr_chunk.rl_mr);
-                       dprintk("RPC:       %s: failed ib_reg_phys_mr "
-                               "%u@0x%llx (%d)... status %i\n",
-                               __func__, len,
-                               (unsigned long long)seg1->mr_dma, nsegs, rc);
-                       while (nsegs--)
-                               rpcrdma_unmap_one(ia, --seg);
-               } else {
-                       seg1->mr_rkey = seg1->mr_chunk.rl_mr->rkey;
-                       seg1->mr_nsegs = nsegs;
-                       seg1->mr_len = len;
-               }
-               }
+               rc = rpcrdma_register_default_external(seg, &nsegs, writing, ia);
                break;
        }
        if (rc)
@@ -1473,7 +1562,6 @@ rpcrdma_deregister_external(struct rpcrdma_mr_seg *seg,
                struct rpcrdma_xprt *r_xprt, void *r)
 {
        struct rpcrdma_ia *ia = &r_xprt->rx_ia;
-       struct rpcrdma_mr_seg *seg1 = seg;
        int nsegs = seg->mr_nsegs, rc;
 
        switch (ia->ri_memreg_strategy) {
@@ -1487,55 +1575,16 @@ rpcrdma_deregister_external(struct rpcrdma_mr_seg *seg,
 #endif
 
        case RPCRDMA_MTHCAFMR:
-               {
-               LIST_HEAD(l);
-               list_add(&seg->mr_chunk.rl_mw->r.fmr->list, &l);
-               rc = ib_unmap_fmr(&l);
-               while (seg1->mr_nsegs--)
-                       rpcrdma_unmap_one(ia, seg++);
-               }
-               if (rc)
-                       dprintk("RPC:       %s: failed ib_unmap_fmr,"
-                               " status %i\n", __func__, rc);
+               rc = rpcrdma_deregister_fmr_external(seg, ia);
                break;
 
        case RPCRDMA_MEMWINDOWS_ASYNC:
        case RPCRDMA_MEMWINDOWS:
-               {
-               struct ib_mw_bind param;
-               BUG_ON(nsegs != 1);
-               param.mr = ia->ri_bind_mem;
-               param.addr = 0ULL;      /* unbind */
-               param.length = 0;
-               param.mw_access_flags = 0;
-               if (r) {
-                       param.wr_id = (u64) (unsigned long) r;
-                       param.send_flags = IB_SEND_SIGNALED;
-                       INIT_CQCOUNT(&r_xprt->rx_ep);
-               } else {
-                       param.wr_id = 0ULL;
-                       param.send_flags = 0;
-                       DECR_CQCOUNT(&r_xprt->rx_ep);
-               }
-               rc = ib_bind_mw(ia->ri_id->qp,
-                               seg->mr_chunk.rl_mw->r.mw, &param);
-               rpcrdma_unmap_one(ia, seg);
-               }
-               if (rc)
-                       dprintk("RPC:       %s: failed ib_(un)bind_mw,"
-                               " status %i\n", __func__, rc);
-               else
-                       r = NULL;       /* will upcall on completion */
+               rc = rpcrdma_deregister_memwin_external(seg, ia, r_xprt, &r);
                break;
 
        default:
-               rc = ib_dereg_mr(seg1->mr_chunk.rl_mr);
-               seg1->mr_chunk.rl_mr = NULL;
-               while (seg1->mr_nsegs--)
-                       rpcrdma_unmap_one(ia, seg++);
-               if (rc)
-                       dprintk("RPC:       %s: failed ib_dereg_mr,"
-                               " status %i\n", __func__, rc);
+               rc = rpcrdma_deregister_default_external(seg, ia);
                break;
        }
        if (r) {