xprtrdma: Remove ->ro_reset

An RPC can exit at any time. When it does so, xprt_rdma_free() is
called, and it calls ->op_unmap().

If ->ro_reset() is running due to a transport disconnect, the two
methods can race while processing the same rpcrdma_mw. The results
are unpredictable.

Because of this, in previous patches I've altered ->ro_map() to
handle MR reset. ->ro_reset() is no longer needed and can be
removed.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Devesh Sharma <devesh.sharma@avagotech.com>
Tested-By: Devesh Sharma <devesh.sharma@avagotech.com>
Reviewed-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This commit is contained in:
Chuck Lever 2015-05-26 11:52:54 -04:00 committed by Anna Schumaker
parent 06b00880b0
commit 3269a94b62
5 changed files with 0 additions and 71 deletions

View File

@ -197,28 +197,6 @@ out_err:
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)
{
@ -242,7 +220,6 @@ const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops = {
.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",
};

View File

@ -430,44 +430,6 @@ out_err:
return nsegs;
}
/* After a disconnect, a flushed FAST_REG_MR can leave an FRMR in
* an unusable state. Find FRMRs in this state and dereg / reg
* each. FRMRs that are VALID and attached to an rpcrdma_req are
* also torn down.
*
* This gives all in-use FRMRs a fresh rkey and leaves them INVALID.
*
* This is invoked only in the transport connect worker in order
* to serialize with rpcrdma_register_frmr_external().
*/
static void
frwr_op_reset(struct rpcrdma_xprt *r_xprt)
{
struct rpcrdma_buffer *buf = &r_xprt->rx_buf;
struct ib_device *device = r_xprt->rx_ia.ri_device;
unsigned int depth = r_xprt->rx_ia.ri_max_frmr_depth;
struct ib_pd *pd = r_xprt->rx_ia.ri_pd;
struct rpcrdma_mw *r;
int rc;
list_for_each_entry(r, &buf->rb_all, mw_all) {
if (r->r.frmr.fr_state == FRMR_IS_INVALID)
continue;
__frwr_release(r);
rc = __frwr_init(r, pd, device, depth);
if (rc) {
dprintk("RPC: %s: mw %p left %s\n",
__func__, r,
(r->r.frmr.fr_state == FRMR_IS_STALE ?
"stale" : "valid"));
continue;
}
r->r.frmr.fr_state = FRMR_IS_INVALID;
}
}
static void
frwr_op_destroy(struct rpcrdma_buffer *buf)
{
@ -490,7 +452,6 @@ const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops = {
.ro_open = frwr_op_open,
.ro_maxpages = frwr_op_maxpages,
.ro_init = frwr_op_init,
.ro_reset = frwr_op_reset,
.ro_destroy = frwr_op_destroy,
.ro_displayname = "frwr",
};

View File

@ -68,11 +68,6 @@ physical_op_unmap(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg)
return 1;
}
static void
physical_op_reset(struct rpcrdma_xprt *r_xprt)
{
}
static void
physical_op_destroy(struct rpcrdma_buffer *buf)
{
@ -84,7 +79,6 @@ const struct rpcrdma_memreg_ops rpcrdma_physical_memreg_ops = {
.ro_open = physical_op_open,
.ro_maxpages = physical_op_maxpages,
.ro_init = physical_op_init,
.ro_reset = physical_op_reset,
.ro_destroy = physical_op_destroy,
.ro_displayname = "physical",
};

View File

@ -891,8 +891,6 @@ retry:
rpcrdma_flush_cqs(ep);
xprt = container_of(ia, struct rpcrdma_xprt, rx_ia);
ia->ri_ops->ro_reset(xprt);
id = rpcrdma_create_id(xprt, ia,
(struct sockaddr *)&xprt->rx_data.addr);
if (IS_ERR(id)) {

View File

@ -352,7 +352,6 @@ struct rpcrdma_memreg_ops {
struct rpcrdma_create_data_internal *);
size_t (*ro_maxpages)(struct rpcrdma_xprt *);
int (*ro_init)(struct rpcrdma_xprt *);
void (*ro_reset)(struct rpcrdma_xprt *);
void (*ro_destroy)(struct rpcrdma_buffer *);
const char *ro_displayname;
};