static void __exit nx842_exit(void) { struct nx842_devdata *old_devdata; unsigned long flags; pr_info("Exiting IBM Power 842 compression driver\n"); spin_lock_irqsave(&devdata_mutex, flags); old_devdata = rcu_dereference_check(devdata, lockdep_is_held(&devdata_mutex)); RCU_INIT_POINTER(devdata, NULL); spin_unlock_irqrestore(&devdata_mutex, flags); synchronize_rcu(); if (old_devdata) dev_set_drvdata(old_devdata->dev, NULL); kfree(old_devdata); vio_unregister_driver(&nx842_driver); }
static void __exit nx842_pseries_exit(void) { struct nx842_devdata *old_devdata; unsigned long flags; crypto_unregister_alg(&nx842_pseries_alg); spin_lock_irqsave(&devdata_mutex, flags); old_devdata = rcu_dereference_check(devdata, lockdep_is_held(&devdata_mutex)); RCU_INIT_POINTER(devdata, NULL); spin_unlock_irqrestore(&devdata_mutex, flags); synchronize_rcu(); if (old_devdata && old_devdata->dev) dev_set_drvdata(old_devdata->dev, NULL); kfree(old_devdata); vio_unregister_driver(&nx842_vio_driver); }
static int __exit nx842_remove(struct vio_dev *viodev) { struct nx842_devdata *old_devdata; unsigned long flags; pr_info("Removing IBM Power 842 compression device\n"); sysfs_remove_group(&viodev->dev.kobj, &nx842_attribute_group); spin_lock_irqsave(&devdata_mutex, flags); old_devdata = rcu_dereference_check(devdata, lockdep_is_held(&devdata_mutex)); of_reconfig_notifier_unregister(&nx842_of_nb); RCU_INIT_POINTER(devdata, NULL); spin_unlock_irqrestore(&devdata_mutex, flags); synchronize_rcu(); dev_set_drvdata(&viodev->dev, NULL); if (old_devdata) kfree(old_devdata->counters); kfree(old_devdata); return 0; }
/** * cgroup_path - generate the path of a cgroup * @cgrp: the cgroup in question * @buf: the buffer to write the path into * @buflen: the length of the buffer * * Called with cgroup_mutex held or else with an RCU-protected cgroup * reference. Writes path of cgroup into buf. Returns 0 on success, * -errno on error. */ int cgroup_path(const struct cgroup *cgrp, char *buf, int buflen) { char *start; struct dentry *dentry = cgrp->dentry; if (!dentry || cgrp == root_cgroup) { /* * Inactive subsystems have no dentry for their root * cgroup */ strcpy(buf, "/"); return 0; } start = buf + buflen; *--start = '\0'; for (;;) { int len = dentry->d_name.len; if ((start -= len) < buf) return -ENAMETOOLONG; memcpy(start, dentry->d_name.name, len); cgrp = cgrp->parent; if (!cgrp) break; dentry = rcu_dereference_check(cgrp->dentry, cgroup_lock_is_held()); if (!cgrp->parent) continue; if (--start < buf) return -ENAMETOOLONG; *start = '/'; } memmove(buf, start, buf + buflen - start); return 0; }
/* Expects to be always run from workqueue - which acts as * read-size critical section for our kind of RCU. */ static void handle_rx(struct vhost_net *net) { struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_RX]; unsigned uninitialized_var(in), log; struct vhost_log *vq_log; struct msghdr msg = { .msg_name = NULL, .msg_namelen = 0, .msg_control = NULL, /* FIXME: get and handle RX aux data. */ .msg_controllen = 0, .msg_iov = vq->iov, .msg_flags = MSG_DONTWAIT, }; struct virtio_net_hdr_mrg_rxbuf hdr = { .hdr.flags = 0, .hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE }; size_t total_len = 0; int err, mergeable; s16 headcount; size_t vhost_hlen, sock_hlen; size_t vhost_len, sock_len; /* TODO: check that we are running from vhost_worker? */ struct socket *sock = rcu_dereference_check(vq->private_data, 1); if (!sock) return; mutex_lock(&vq->mutex); vhost_disable_notify(&net->dev, vq); vhost_hlen = vq->vhost_hlen; sock_hlen = vq->sock_hlen; vq_log = unlikely(vhost_has_feature(&net->dev, VHOST_F_LOG_ALL)) ? vq->log : NULL; mergeable = vhost_has_feature(&net->dev, VIRTIO_NET_F_MRG_RXBUF); while ((sock_len = peek_head_len(sock->sk))) { sock_len += sock_hlen; vhost_len = sock_len + vhost_hlen; headcount = get_rx_bufs(vq, vq->heads, vhost_len, &in, vq_log, &log, likely(mergeable) ? UIO_MAXIOV : 1); /* On error, stop handling until the next kick. */ if (unlikely(headcount < 0)) break; /* OK, now we need to know about added descriptors. */ if (!headcount) { if (unlikely(vhost_enable_notify(&net->dev, vq))) { /* They have slipped one in as we were * doing that: check again. */ vhost_disable_notify(&net->dev, vq); continue; } /* Nothing new? Wait for eventfd to tell us * they refilled. */ break; } /* We don't need to be notified again. */ if (unlikely((vhost_hlen))) /* Skip header. TODO: support TSO. */ move_iovec_hdr(vq->iov, vq->hdr, vhost_hlen, in); else /* Copy the header for use in VIRTIO_NET_F_MRG_RXBUF: * needed because recvmsg can modify msg_iov. */ copy_iovec_hdr(vq->iov, vq->hdr, sock_hlen, in); msg.msg_iovlen = in; err = sock->ops->recvmsg(NULL, sock, &msg, sock_len, MSG_DONTWAIT | MSG_TRUNC); /* Userspace might have consumed the packet meanwhile: * it's not supposed to do this usually, but might be hard * to prevent. Discard data we got (if any) and keep going. */ if (unlikely(err != sock_len)) { pr_debug("Discarded rx packet: " " len %d, expected %zd\n", err, sock_len); vhost_discard_vq_desc(vq, headcount); continue; } if (unlikely(vhost_hlen) && memcpy_toiovecend(vq->hdr, (unsigned char *)&hdr, 0, vhost_hlen)) { vq_err(vq, "Unable to write vnet_hdr at addr %p\n", vq->iov->iov_base); break; } /* TODO: Should check and handle checksum. */ if (likely(mergeable) && memcpy_toiovecend(vq->hdr, (unsigned char *)&headcount, offsetof(typeof(hdr), num_buffers), sizeof hdr.num_buffers)) { vq_err(vq, "Failed num_buffers write"); vhost_discard_vq_desc(vq, headcount); break; } vhost_add_used_and_signal_n(&net->dev, vq, vq->heads, headcount); if (unlikely(vq_log)) vhost_log_write(vq, vq_log, log, vhost_len); total_len += vhost_len; if (unlikely(total_len >= VHOST_NET_WEIGHT)) { vhost_poll_queue(&vq->poll); break; } } mutex_unlock(&vq->mutex); } static void handle_tx_kick(struct vhost_work *work) { struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, poll.work); struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); handle_tx(net); } static void handle_rx_kick(struct vhost_work *work) { struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, poll.work); struct vhost_net *net = container_of(vq->dev, struct vhost_net, dev); handle_rx(net); } static void handle_tx_net(struct vhost_work *work) { struct vhost_net *net = container_of(work, struct vhost_net, poll[VHOST_NET_VQ_TX].work); handle_tx(net); } static void handle_rx_net(struct vhost_work *work) { struct vhost_net *net = container_of(work, struct vhost_net, poll[VHOST_NET_VQ_RX].work); handle_rx(net); } static int vhost_net_open(struct inode *inode, struct file *f) { struct vhost_net *n = kmalloc(sizeof *n, GFP_KERNEL); struct vhost_dev *dev; int r; if (!n) return -ENOMEM; dev = &n->dev; n->vqs[VHOST_NET_VQ_TX].handle_kick = handle_tx_kick; n->vqs[VHOST_NET_VQ_RX].handle_kick = handle_rx_kick; r = vhost_dev_init(dev, n->vqs, VHOST_NET_VQ_MAX); if (r < 0) { kfree(n); return r; } vhost_poll_init(n->poll + VHOST_NET_VQ_TX, handle_tx_net, POLLOUT, dev); vhost_poll_init(n->poll + VHOST_NET_VQ_RX, handle_rx_net, POLLIN, dev); n->tx_poll_state = VHOST_NET_POLL_DISABLED; f->private_data = n; return 0; } static void vhost_net_disable_vq(struct vhost_net *n, struct vhost_virtqueue *vq) { if (!vq->private_data) return; if (vq == n->vqs + VHOST_NET_VQ_TX) { tx_poll_stop(n); n->tx_poll_state = VHOST_NET_POLL_DISABLED; } else vhost_poll_stop(n->poll + VHOST_NET_VQ_RX); } static void vhost_net_enable_vq(struct vhost_net *n, struct vhost_virtqueue *vq) { struct socket *sock; sock = rcu_dereference_protected(vq->private_data, lockdep_is_held(&vq->mutex)); if (!sock) return; if (vq == n->vqs + VHOST_NET_VQ_TX) { n->tx_poll_state = VHOST_NET_POLL_STOPPED; tx_poll_start(n, sock); } else vhost_poll_start(n->poll + VHOST_NET_VQ_RX, sock->file); } static struct socket *vhost_net_stop_vq(struct vhost_net *n, struct vhost_virtqueue *vq) { struct socket *sock; mutex_lock(&vq->mutex); sock = rcu_dereference_protected(vq->private_data, lockdep_is_held(&vq->mutex)); vhost_net_disable_vq(n, vq); rcu_assign_pointer(vq->private_data, NULL); mutex_unlock(&vq->mutex); return sock; } static void vhost_net_stop(struct vhost_net *n, struct socket **tx_sock, struct socket **rx_sock) { *tx_sock = vhost_net_stop_vq(n, n->vqs + VHOST_NET_VQ_TX); *rx_sock = vhost_net_stop_vq(n, n->vqs + VHOST_NET_VQ_RX); } static void vhost_net_flush_vq(struct vhost_net *n, int index) { vhost_poll_flush(n->poll + index); vhost_poll_flush(&n->dev.vqs[index].poll); }
/* Expects to be always run from workqueue - which acts as * read-size critical section for our kind of RCU. */ static void handle_tx(struct vhost_net *net) { struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_TX]; unsigned out, in, s; int head; struct msghdr msg = { .msg_name = NULL, .msg_namelen = 0, .msg_control = NULL, .msg_controllen = 0, .msg_iov = vq->iov, .msg_flags = MSG_DONTWAIT, }; size_t len, total_len = 0; int err, wmem; size_t hdr_size; struct socket *sock; struct vhost_ubuf_ref *uninitialized_var(ubufs); bool zcopy; /* TODO: check that we are running from vhost_worker? */ sock = rcu_dereference_check(vq->private_data, 1); if (!sock) return; wmem = atomic_read(&sock->sk->sk_wmem_alloc); if (wmem >= sock->sk->sk_sndbuf) { mutex_lock(&vq->mutex); tx_poll_start(net, sock); mutex_unlock(&vq->mutex); return; } mutex_lock(&vq->mutex); vhost_disable_notify(&net->dev, vq); if (wmem < sock->sk->sk_sndbuf / 2) tx_poll_stop(net); hdr_size = vq->vhost_hlen; zcopy = vhost_sock_zcopy(sock); for (;;) { /* Release DMAs done buffers first */ if (zcopy) vhost_zerocopy_signal_used(vq); head = vhost_get_vq_desc(&net->dev, vq, vq->iov, ARRAY_SIZE(vq->iov), &out, &in, NULL, NULL); /* On error, stop handling until the next kick. */ if (unlikely(head < 0)) break; /* Nothing new? Wait for eventfd to tell us they refilled. */ if (head == vq->num) { int num_pends; wmem = atomic_read(&sock->sk->sk_wmem_alloc); if (wmem >= sock->sk->sk_sndbuf * 3 / 4) { tx_poll_start(net, sock); set_bit(SOCK_ASYNC_NOSPACE, &sock->flags); break; } /* If more outstanding DMAs, queue the work. * Handle upend_idx wrap around */ num_pends = likely(vq->upend_idx >= vq->done_idx) ? (vq->upend_idx - vq->done_idx) : (vq->upend_idx + UIO_MAXIOV - vq->done_idx); if (unlikely(num_pends > VHOST_MAX_PEND)) { tx_poll_start(net, sock); set_bit(SOCK_ASYNC_NOSPACE, &sock->flags); break; } if (unlikely(vhost_enable_notify(&net->dev, vq))) { vhost_disable_notify(&net->dev, vq); continue; } break; } if (in) { vq_err(vq, "Unexpected descriptor format for TX: " "out %d, int %d\n", out, in); break; } /* Skip header. TODO: support TSO. */ s = move_iovec_hdr(vq->iov, vq->hdr, hdr_size, out); msg.msg_iovlen = out; len = iov_length(vq->iov, out); /* Sanity check */ if (!len) { vq_err(vq, "Unexpected header len for TX: " "%zd expected %zd\n", iov_length(vq->hdr, s), hdr_size); break; } /* use msg_control to pass vhost zerocopy ubuf info to skb */ if (zcopy) { vq->heads[vq->upend_idx].id = head; if (len < VHOST_GOODCOPY_LEN) { /* copy don't need to wait for DMA done */ vq->heads[vq->upend_idx].len = VHOST_DMA_DONE_LEN; msg.msg_control = NULL; msg.msg_controllen = 0; ubufs = NULL; } else { struct ubuf_info *ubuf = &vq->ubuf_info[head]; vq->heads[vq->upend_idx].len = len; ubuf->callback = vhost_zerocopy_callback; ubuf->ctx = vq->ubufs; ubuf->desc = vq->upend_idx; msg.msg_control = ubuf; msg.msg_controllen = sizeof(ubuf); ubufs = vq->ubufs; kref_get(&ubufs->kref); } vq->upend_idx = (vq->upend_idx + 1) % UIO_MAXIOV; } /* TODO: Check specific error and bomb out unless ENOBUFS? */ err = sock->ops->sendmsg(NULL, sock, &msg, len); if (unlikely(err < 0)) { if (zcopy) { if (ubufs) vhost_ubuf_put(ubufs); vq->upend_idx = ((unsigned)vq->upend_idx - 1) % UIO_MAXIOV; } vhost_discard_vq_desc(vq, 1); tx_poll_start(net, sock); break; } if (err != len) pr_debug("Truncated TX packet: " " len %d != %zd\n", err, len); if (!zcopy) vhost_add_used_and_signal(&net->dev, vq, head, 0); total_len += len; if (unlikely(total_len >= VHOST_NET_WEIGHT)) { vhost_poll_queue(&vq->poll); break; } } mutex_unlock(&vq->mutex); } static int peek_head_len(struct sock *sk) { struct sk_buff *head; int len = 0; unsigned long flags; spin_lock_irqsave(&sk->sk_receive_queue.lock, flags); head = skb_peek(&sk->sk_receive_queue); if (likely(head)) { len = head->len; if (vlan_tx_tag_present(head)) len += VLAN_HLEN; } spin_unlock_irqrestore(&sk->sk_receive_queue.lock, flags); return len; } /* This is a multi-buffer version of vhost_get_desc, that works if * vq has read descriptors only. * @vq - the relevant virtqueue * @datalen - data length we'll be reading * @iovcount - returned count of io vectors we fill * @log - vhost log * @log_num - log offset * @quota - headcount quota, 1 for big buffer * returns number of buffer heads allocated, negative on error */ static int get_rx_bufs(struct vhost_virtqueue *vq, struct vring_used_elem *heads, int datalen, unsigned *iovcount, struct vhost_log *log, unsigned *log_num, unsigned int quota) { unsigned int out, in; int seg = 0; int headcount = 0; unsigned d; int r, nlogs = 0; while (datalen > 0 && headcount < quota) { if (unlikely(seg >= UIO_MAXIOV)) { r = -ENOBUFS; goto err; } d = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg, ARRAY_SIZE(vq->iov) - seg, &out, &in, log, log_num); if (d == vq->num) { r = 0; goto err; } if (unlikely(out || in <= 0)) { vq_err(vq, "unexpected descriptor format for RX: " "out %d, in %d\n", out, in); r = -EINVAL; goto err; } if (unlikely(log)) { nlogs += *log_num; log += *log_num; } heads[headcount].id = d; heads[headcount].len = iov_length(vq->iov + seg, in); datalen -= heads[headcount].len; ++headcount; seg += in; } heads[headcount - 1].len += datalen; *iovcount = seg; if (unlikely(log)) *log_num = nlogs; return headcount; err: vhost_discard_vq_desc(vq, headcount); return r; }
/* Expects to be always run from workqueue - which acts as * read-size critical section for our kind of RCU. */ static void handle_tx(struct vhost_net *net) { struct vhost_virtqueue *vq = &net->dev.vqs[VHOST_NET_VQ_TX]; unsigned out, in, s; int head; struct msghdr msg = { .msg_name = NULL, .msg_namelen = 0, .msg_control = NULL, .msg_controllen = 0, .msg_iov = vq->iov, .msg_flags = MSG_DONTWAIT, }; size_t len, total_len = 0; int err, wmem; size_t hdr_size; struct socket *sock; /* TODO: check that we are running from vhost_worker? */ sock = rcu_dereference_check(vq->private_data, 1); if (!sock) return; wmem = atomic_read(&sock->sk->sk_wmem_alloc); if (wmem >= sock->sk->sk_sndbuf) { mutex_lock(&vq->mutex); tx_poll_start(net, sock); mutex_unlock(&vq->mutex); return; } mutex_lock(&vq->mutex); vhost_disable_notify(vq); if (wmem < sock->sk->sk_sndbuf / 2) tx_poll_stop(net); hdr_size = vq->vhost_hlen; for (;;) { head = vhost_get_vq_desc(&net->dev, vq, vq->iov, ARRAY_SIZE(vq->iov), &out, &in, NULL, NULL); /* On error, stop handling until the next kick. */ if (unlikely(head < 0)) break; /* Nothing new? Wait for eventfd to tell us they refilled. */ if (head == vq->num) { wmem = atomic_read(&sock->sk->sk_wmem_alloc); if (wmem >= sock->sk->sk_sndbuf * 3 / 4) { tx_poll_start(net, sock); set_bit(SOCK_ASYNC_NOSPACE, &sock->flags); break; } if (unlikely(vhost_enable_notify(vq))) { vhost_disable_notify(vq); continue; } break; } if (in) { vq_err(vq, "Unexpected descriptor format for TX: " "out %d, int %d\n", out, in); break; } /* Skip header. TODO: support TSO. */ s = move_iovec_hdr(vq->iov, vq->hdr, hdr_size, out); msg.msg_iovlen = out; len = iov_length(vq->iov, out); /* Sanity check */ if (!len) { vq_err(vq, "Unexpected header len for TX: " "%zd expected %zd\n", iov_length(vq->hdr, s), hdr_size); break; } /* TODO: Check specific error and bomb out unless ENOBUFS? */ err = sock->ops->sendmsg(NULL, sock, &msg, len); if (unlikely(err < 0)) { vhost_discard_vq_desc(vq, 1); tx_poll_start(net, sock); break; } if (err != len) pr_debug("Truncated TX packet: " " len %d != %zd\n", err, len); vhost_add_used_and_signal(&net->dev, vq, head, 0); total_len += len; if (unlikely(total_len >= VHOST_NET_WEIGHT)) { vhost_poll_queue(&vq->poll); break; } } mutex_unlock(&vq->mutex); } static int peek_head_len(struct sock *sk) { struct sk_buff *head; int len = 0; unsigned long flags; spin_lock_irqsave(&sk->sk_receive_queue.lock, flags); head = skb_peek(&sk->sk_receive_queue); if (likely(head)) len = head->len; spin_unlock_irqrestore(&sk->sk_receive_queue.lock, flags); return len; } /* This is a multi-buffer version of vhost_get_desc, that works if * vq has read descriptors only. * @vq - the relevant virtqueue * @datalen - data length we'll be reading * @iovcount - returned count of io vectors we fill * @log - vhost log * @log_num - log offset * @quota - headcount quota, 1 for big buffer * returns number of buffer heads allocated, negative on error */ static int get_rx_bufs(struct vhost_virtqueue *vq, struct vring_used_elem *heads, int datalen, unsigned *iovcount, struct vhost_log *log, unsigned *log_num, unsigned int quota) { unsigned int out, in; int seg = 0; int headcount = 0; unsigned d; int r, nlogs = 0; while (datalen > 0 && headcount < quota) { if (unlikely(seg >= UIO_MAXIOV)) { r = -ENOBUFS; goto err; } d = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg, ARRAY_SIZE(vq->iov) - seg, &out, &in, log, log_num); if (d == vq->num) { r = 0; goto err; } if (unlikely(out || in <= 0)) { vq_err(vq, "unexpected descriptor format for RX: " "out %d, in %d\n", out, in); r = -EINVAL; goto err; } if (unlikely(log)) { nlogs += *log_num; log += *log_num; } heads[headcount].id = d; heads[headcount].len = iov_length(vq->iov + seg, in); datalen -= heads[headcount].len; ++headcount; seg += in; } heads[headcount - 1].len += datalen; *iovcount = seg; if (unlikely(log)) *log_num = nlogs; return headcount; err: vhost_discard_vq_desc(vq, headcount); return r; }
static int nx842_probe(struct vio_dev *viodev, const struct vio_device_id *id) { struct nx842_devdata *old_devdata, *new_devdata = NULL; unsigned long flags; int ret = 0; new_devdata = kzalloc(sizeof(*new_devdata), GFP_NOFS); if (!new_devdata) return -ENOMEM; new_devdata->counters = kzalloc(sizeof(*new_devdata->counters), GFP_NOFS); if (!new_devdata->counters) { kfree(new_devdata); return -ENOMEM; } spin_lock_irqsave(&devdata_mutex, flags); old_devdata = rcu_dereference_check(devdata, lockdep_is_held(&devdata_mutex)); if (old_devdata && old_devdata->vdev != NULL) { dev_err(&viodev->dev, "%s: Attempt to register more than one instance of the hardware\n", __func__); ret = -1; goto error_unlock; } dev_set_drvdata(&viodev->dev, NULL); new_devdata->vdev = viodev; new_devdata->dev = &viodev->dev; nx842_OF_set_defaults(new_devdata); rcu_assign_pointer(devdata, new_devdata); spin_unlock_irqrestore(&devdata_mutex, flags); synchronize_rcu(); kfree(old_devdata); of_reconfig_notifier_register(&nx842_of_nb); ret = nx842_OF_upd(NULL); if (ret) goto error; ret = crypto_register_alg(&nx842_pseries_alg); if (ret) { dev_err(&viodev->dev, "could not register comp alg: %d\n", ret); goto error; } rcu_read_lock(); dev_set_drvdata(&viodev->dev, rcu_dereference(devdata)); rcu_read_unlock(); if (sysfs_create_group(&viodev->dev.kobj, &nx842_attribute_group)) { dev_err(&viodev->dev, "could not create sysfs device attributes\n"); ret = -1; goto error; } return 0; error_unlock: spin_unlock_irqrestore(&devdata_mutex, flags); if (new_devdata) kfree(new_devdata->counters); kfree(new_devdata); error: return ret; }
/** * * nx842_OF_upd -- Handle OF properties updates for the device. * * Set all properties from the OF tree. Optionally, a new property * can be provided by the @new_prop pointer to overwrite an existing value. * The device will remain disabled until all values are valid, this function * will return an error for updates unless all values are valid. * * @new_prop: If not NULL, this property is being updated. If NULL, update * all properties from the current values in the OF tree. * * Returns: * 0 - Success * -ENOMEM - Could not allocate memory for new devdata structure * -EINVAL - property value not found, new_prop is not a recognized * property for the device or property value is not valid. * -ENODEV - Device is not available */ static int nx842_OF_upd(struct property *new_prop) { struct nx842_devdata *old_devdata = NULL; struct nx842_devdata *new_devdata = NULL; struct device_node *of_node = NULL; struct property *status = NULL; struct property *maxsglen = NULL; struct property *maxsyncop = NULL; int ret = 0; unsigned long flags; new_devdata = kzalloc(sizeof(*new_devdata), GFP_NOFS); if (!new_devdata) return -ENOMEM; spin_lock_irqsave(&devdata_mutex, flags); old_devdata = rcu_dereference_check(devdata, lockdep_is_held(&devdata_mutex)); if (old_devdata) of_node = old_devdata->dev->of_node; if (!old_devdata || !of_node) { pr_err("%s: device is not available\n", __func__); spin_unlock_irqrestore(&devdata_mutex, flags); kfree(new_devdata); return -ENODEV; } memcpy(new_devdata, old_devdata, sizeof(*old_devdata)); new_devdata->counters = old_devdata->counters; /* Set ptrs for existing properties */ status = of_find_property(of_node, "status", NULL); maxsglen = of_find_property(of_node, "ibm,max-sg-len", NULL); maxsyncop = of_find_property(of_node, "ibm,max-sync-cop", NULL); if (!status || !maxsglen || !maxsyncop) { dev_err(old_devdata->dev, "%s: Could not locate device properties\n", __func__); ret = -EINVAL; goto error_out; } /* * If this is a property update, there are only certain properties that * we care about. Bail if it isn't in the below list */ if (new_prop && (strncmp(new_prop->name, "status", new_prop->length) || strncmp(new_prop->name, "ibm,max-sg-len", new_prop->length) || strncmp(new_prop->name, "ibm,max-sync-cop", new_prop->length))) goto out; /* Perform property updates */ ret = nx842_OF_upd_status(status); if (ret) goto error_out; ret = nx842_OF_upd_maxsglen(new_devdata, maxsglen); if (ret) goto error_out; ret = nx842_OF_upd_maxsyncop(new_devdata, maxsyncop); if (ret) goto error_out; out: dev_info(old_devdata->dev, "%s: max_sync_size new:%u old:%u\n", __func__, new_devdata->max_sync_size, old_devdata->max_sync_size); dev_info(old_devdata->dev, "%s: max_sync_sg new:%u old:%u\n", __func__, new_devdata->max_sync_sg, old_devdata->max_sync_sg); dev_info(old_devdata->dev, "%s: max_sg_len new:%u old:%u\n", __func__, new_devdata->max_sg_len, old_devdata->max_sg_len); rcu_assign_pointer(devdata, new_devdata); spin_unlock_irqrestore(&devdata_mutex, flags); synchronize_rcu(); dev_set_drvdata(new_devdata->dev, new_devdata); kfree(old_devdata); return 0; error_out: if (new_devdata) { dev_info(old_devdata->dev, "%s: device disabled\n", __func__); nx842_OF_set_defaults(new_devdata); rcu_assign_pointer(devdata, new_devdata); spin_unlock_irqrestore(&devdata_mutex, flags); synchronize_rcu(); dev_set_drvdata(new_devdata->dev, new_devdata); kfree(old_devdata); } else { dev_err(old_devdata->dev, "%s: could not update driver from hardware\n", __func__); spin_unlock_irqrestore(&devdata_mutex, flags); } if (!ret) ret = -EINVAL; return ret; }