+static int mthca_alloc_resize_buf(struct mthca_dev *dev, struct mthca_cq *cq,
+ int entries)
+{
+ int ret;
+
+ spin_lock_irq(&cq->lock);
+ if (cq->resize_buf) {
+ ret = -EBUSY;
+ goto unlock;
+ }
+
+ cq->resize_buf = kmalloc(sizeof *cq->resize_buf, GFP_ATOMIC);
+ if (!cq->resize_buf) {
+ ret = -ENOMEM;
+ goto unlock;
+ }
+
+ cq->resize_buf->state = CQ_RESIZE_ALLOC;
+
+ ret = 0;
+
+unlock:
+ spin_unlock_irq(&cq->lock);
+
+ if (ret)
+ return ret;
+
+ ret = mthca_alloc_cq_buf(dev, &cq->resize_buf->buf, entries);
+ if (ret) {
+ spin_lock_irq(&cq->lock);
+ kfree(cq->resize_buf);
+ cq->resize_buf = NULL;
+ spin_unlock_irq(&cq->lock);
+ return ret;
+ }
+
+ cq->resize_buf->cqe = entries - 1;
+
+ spin_lock_irq(&cq->lock);
+ cq->resize_buf->state = CQ_RESIZE_READY;
+ spin_unlock_irq(&cq->lock);
+
+ return 0;
+}
+
+static int mthca_resize_cq(struct ib_cq *ibcq, int entries, struct ib_udata *udata)
+{
+ struct mthca_dev *dev = to_mdev(ibcq->device);
+ struct mthca_cq *cq = to_mcq(ibcq);
+ struct mthca_resize_cq ucmd;
+ u32 lkey;
+ u8 status;
+ int ret;
+
+ if (entries < 1 || entries > dev->limits.max_cqes)
+ return -EINVAL;
+
+ entries = roundup_pow_of_two(entries + 1);
+ if (entries == ibcq->cqe + 1)
+ return 0;
+
+ if (cq->is_kernel) {
+ ret = mthca_alloc_resize_buf(dev, cq, entries);
+ if (ret)
+ return ret;
+ lkey = cq->resize_buf->buf.mr.ibmr.lkey;
+ } else {
+ if (ib_copy_from_udata(&ucmd, udata, sizeof ucmd))
+ return -EFAULT;
+ lkey = ucmd.lkey;
+ }
+
+ ret = mthca_RESIZE_CQ(dev, cq->cqn, lkey, long_log2(entries), &status);
+ if (status)
+ ret = -EINVAL;
+
+ if (ret) {
+ if (cq->resize_buf) {
+ mthca_free_cq_buf(dev, &cq->resize_buf->buf,
+ cq->resize_buf->cqe);
+ kfree(cq->resize_buf);
+ spin_lock_irq(&cq->lock);
+ cq->resize_buf = NULL;
+ spin_unlock_irq(&cq->lock);
+ }
+ return ret;
+ }
+
+ if (cq->is_kernel) {
+ struct mthca_cq_buf tbuf;
+ int tcqe;
+
+ spin_lock_irq(&cq->lock);
+ if (cq->resize_buf->state == CQ_RESIZE_READY) {
+ mthca_cq_resize_copy_cqes(cq);
+ tbuf = cq->buf;
+ tcqe = cq->ibcq.cqe;
+ cq->buf = cq->resize_buf->buf;
+ cq->ibcq.cqe = cq->resize_buf->cqe;
+ } else {
+ tbuf = cq->resize_buf->buf;
+ tcqe = cq->resize_buf->cqe;
+ }
+
+ kfree(cq->resize_buf);
+ cq->resize_buf = NULL;
+ spin_unlock_irq(&cq->lock);
+
+ mthca_free_cq_buf(dev, &tbuf, tcqe);
+ } else
+ ibcq->cqe = entries - 1;
+
+ return 0;
+}
+