* can take tens of usecs to complete.
*/
+/* Normal operation
+ *
+ * A Memory Region is prepared for RDMA READ or WRITE using the
+ * ib_map_phys_fmr verb (fmr_op_map). When the RDMA operation is
+ * finished, the Memory Region is unmapped using the ib_unmap_fmr
+ * verb (fmr_op_unmap).
+ */
+
+/* Transport recovery
+ *
+ * After a transport reconnect, fmr_op_map re-uses the MR already
+ * allocated for the RPC, but generates a fresh rkey then maps the
+ * MR again. This process is synchronous.
+ */
+
#include "xprt_rdma.h"
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
struct rpcrdma_mw *r;
int i, rc;
+ spin_lock_init(&buf->rb_mwlock);
INIT_LIST_HEAD(&buf->rb_mws);
INIT_LIST_HEAD(&buf->rb_all);
- i = (buf->rb_max_requests + 1) * RPCRDMA_MAX_SEGS;
- dprintk("RPC: %s: initializing %d FMRs\n", __func__, i);
+ i = max_t(int, RPCRDMA_MAX_DATA_SEGS / RPCRDMA_MAX_FMR_SGES, 1);
+ i += 2; /* head + tail */
+ i *= buf->rb_max_requests; /* one set for each RPC slot */
+ dprintk("RPC: %s: initalizing %d FMRs\n", __func__, i);
+ rc = -ENOMEM;
while (i--) {
r = kzalloc(sizeof(*r), GFP_KERNEL);
if (!r)
- return -ENOMEM;
+ goto out;
- r->r.fmr = ib_alloc_fmr(pd, mr_access_flags, &fmr_attr);
- if (IS_ERR(r->r.fmr))
+ r->r.fmr.physaddrs = kmalloc(RPCRDMA_MAX_FMR_SGES *
+ sizeof(u64), GFP_KERNEL);
+ if (!r->r.fmr.physaddrs)
+ goto out_free;
+
+ r->r.fmr.fmr = ib_alloc_fmr(pd, mr_access_flags, &fmr_attr);
+ if (IS_ERR(r->r.fmr.fmr))
goto out_fmr_err;
list_add(&r->mw_list, &buf->rb_mws);
return 0;
out_fmr_err:
- rc = PTR_ERR(r->r.fmr);
+ rc = PTR_ERR(r->r.fmr.fmr);
dprintk("RPC: %s: ib_alloc_fmr status %i\n", __func__, rc);
+ kfree(r->r.fmr.physaddrs);
+out_free:
kfree(r);
+out:
return rc;
}
+static int
+__fmr_unmap(struct rpcrdma_mw *r)
+{
+ LIST_HEAD(l);
+
+ list_add(&r->r.fmr.fmr->list, &l);
+ return ib_unmap_fmr(&l);
+}
+
/* Use the ib_map_phys_fmr() verb to register a memory region
* for remote access via RDMA READ or RDMA WRITE.
*/
int nsegs, bool writing)
{
struct rpcrdma_ia *ia = &r_xprt->rx_ia;
- struct ib_device *device = ia->ri_id->device;
+ struct ib_device *device = ia->ri_device;
enum dma_data_direction direction = rpcrdma_data_dir(writing);
struct rpcrdma_mr_seg *seg1 = seg;
- struct rpcrdma_mw *mw = seg1->rl_mw;
- u64 physaddrs[RPCRDMA_MAX_DATA_SEGS];
int len, pageoff, i, rc;
+ struct rpcrdma_mw *mw;
+
+ mw = seg1->rl_mw;
+ seg1->rl_mw = NULL;
+ if (!mw) {
+ mw = rpcrdma_get_mw(r_xprt);
+ if (!mw)
+ return -ENOMEM;
+ } else {
+ /* this is a retransmit; generate a fresh rkey */
+ rc = __fmr_unmap(mw);
+ if (rc)
+ return rc;
+ }
pageoff = offset_in_page(seg1->mr_offset);
seg1->mr_offset -= pageoff; /* start of page */
nsegs = RPCRDMA_MAX_FMR_SGES;
for (i = 0; i < nsegs;) {
rpcrdma_map_one(device, seg, direction);
- physaddrs[i] = seg->mr_dma;
+ mw->r.fmr.physaddrs[i] = seg->mr_dma;
len += seg->mr_len;
++seg;
++i;
break;
}
- rc = ib_map_phys_fmr(mw->r.fmr, physaddrs, i, seg1->mr_dma);
+ rc = ib_map_phys_fmr(mw->r.fmr.fmr, mw->r.fmr.physaddrs,
+ i, seg1->mr_dma);
if (rc)
goto out_maperr;
- seg1->mr_rkey = mw->r.fmr->rkey;
+ seg1->rl_mw = mw;
+ seg1->mr_rkey = mw->r.fmr.fmr->rkey;
seg1->mr_base = seg1->mr_dma + pageoff;
seg1->mr_nsegs = i;
seg1->mr_len = len;
{
struct rpcrdma_ia *ia = &r_xprt->rx_ia;
struct rpcrdma_mr_seg *seg1 = seg;
- struct ib_device *device;
+ struct rpcrdma_mw *mw = seg1->rl_mw;
int rc, nsegs = seg->mr_nsegs;
- LIST_HEAD(l);
- list_add(&seg1->rl_mw->r.fmr->list, &l);
- rc = ib_unmap_fmr(&l);
- read_lock(&ia->ri_qplock);
- device = ia->ri_id->device;
+ dprintk("RPC: %s: FMR %p\n", __func__, mw);
+
+ seg1->rl_mw = NULL;
while (seg1->mr_nsegs--)
- rpcrdma_unmap_one(device, seg++);
- read_unlock(&ia->ri_qplock);
+ rpcrdma_unmap_one(ia->ri_device, seg++);
+ rc = __fmr_unmap(mw);
if (rc)
goto out_err;
+ rpcrdma_put_mw(r_xprt, mw);
return nsegs;
out_err:
+ /* The FMR is abandoned, but remains in rb_all. fmr_op_destroy
+ * will attempt to release it when the transport is destroyed.
+ */
dprintk("RPC: %s: ib_unmap_fmr status %i\n", __func__, rc);
return nsegs;
}
-/* After a disconnect, unmap all FMRs.
- *
- * This is invoked only in the transport connect worker in order
- * to serialize with rpcrdma_register_fmr_external().
- */
-static void
-fmr_op_reset(struct rpcrdma_xprt *r_xprt)
-{
- struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
- struct rpcrdma_mw *r;
- LIST_HEAD(list);
- int rc;
-
- list_for_each_entry(r, &buf->rb_all, mw_all)
- list_add(&r->r.fmr->list, &list);
-
- rc = ib_unmap_fmr(&list);
- if (rc)
- dprintk("RPC: %s: ib_unmap_fmr failed %i\n",
- __func__, rc);
-}
-
static void
fmr_op_destroy(struct rpcrdma_buffer *buf)
{
while (!list_empty(&buf->rb_all)) {
r = list_entry(buf->rb_all.next, struct rpcrdma_mw, mw_all);
list_del(&r->mw_all);
- rc = ib_dealloc_fmr(r->r.fmr);
+ kfree(r->r.fmr.physaddrs);
+
+ rc = ib_dealloc_fmr(r->r.fmr.fmr);
if (rc)
dprintk("RPC: %s: ib_dealloc_fmr failed %i\n",
__func__, rc);
+
kfree(r);
}
}
.ro_open = fmr_op_open,
.ro_maxpages = fmr_op_maxpages,
.ro_init = fmr_op_init,
- .ro_reset = fmr_op_reset,
.ro_destroy = fmr_op_destroy,
.ro_displayname = "fmr",
};
Code Review / kvmfornfv.git / blobdiff