9P: Fix fcall allocation for rdma

The current code assumes that when a request in the request array
does have a tc, it also has a rc.

This is normally true, but not always : when using RDMA, req->rc
will temporarily be set to NULL after the request has been sent.
That is usually OK though, as when the reply arrives, req->rc will be
reassigned to a sane value before the request is recycled.

But there is a catch : if the request is flushed, the reply will never
arrive, and req->rc will be NULL, but not req->tc.

This patch fixes p9_tag_alloc to take this into account.

Signed-off-by: Simon Derr <simon.derr@bull.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
This commit is contained in:
Simon Derr 2013-06-21 15:32:34 +02:00 committed by Eric Van Hensbergen
parent d9a738597f
commit ea071aa136

View File

@ -258,27 +258,25 @@ p9_tag_alloc(struct p9_client *c, u16 tag, unsigned int max_size)
req = &c->reqs[row][col];
if (!req->tc) {
req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_NOFS);
if (!req->wq) {
pr_err("Couldn't grow tag array\n");
return ERR_PTR(-ENOMEM);
}
if (!req->wq)
goto grow_failed;
init_waitqueue_head(req->wq);
req->tc = kmalloc(sizeof(struct p9_fcall) + alloc_msize,
GFP_NOFS);
if (!req->tc)
goto grow_failed;
req->tc->capacity = alloc_msize;
req->tc->sdata = (char *) req->tc + sizeof(struct p9_fcall);
}
if (!req->rc) {
req->rc = kmalloc(sizeof(struct p9_fcall) + alloc_msize,
GFP_NOFS);
if ((!req->tc) || (!req->rc)) {
pr_err("Couldn't grow tag array\n");
kfree(req->tc);
kfree(req->rc);
kfree(req->wq);
req->tc = req->rc = NULL;
req->wq = NULL;
return ERR_PTR(-ENOMEM);
}
req->tc->capacity = alloc_msize;
if (!req->rc)
goto grow_failed;
req->rc->capacity = alloc_msize;
req->tc->sdata = (char *) req->tc + sizeof(struct p9_fcall);
req->rc->sdata = (char *) req->rc + sizeof(struct p9_fcall);
}
@ -288,7 +286,16 @@ p9_tag_alloc(struct p9_client *c, u16 tag, unsigned int max_size)
req->tc->tag = tag-1;
req->status = REQ_STATUS_ALLOC;
return &c->reqs[row][col];
return req;
grow_failed:
pr_err("Couldn't grow tag array\n");
kfree(req->tc);
kfree(req->rc);
kfree(req->wq);
req->tc = req->rc = NULL;
req->wq = NULL;
return ERR_PTR(-ENOMEM);
}
/**