Commit ea071aa1 authored by Simon Derr's avatar Simon Derr Committed by Eric Van Hensbergen
Browse files

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: default avatarSimon Derr <simon.derr@bull.net>
Signed-off-by: default avatarEric Van Hensbergen <ericvh@gmail.com>
parent d9a73859

net/9p/client.c

+23 −16
Original line number Diff line number Diff line
@@ -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);

}



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