From: Halil Pasic Date: Mon, 1 Oct 2018 19:01:58 +0200 Subject: virtio/s390: use DMA memory for ccw I/O and classic notifiers Git-commit: 48720ba56891570e3b750b271d80efb631478630 Patch-mainline: v5.2-rc1 References: jsc#SLE-6197 FATE#327012 bsc#1140559 LTC#173150 Before virtio-ccw could get away with not using DMA API for the pieces of memory it does ccw I/O with. With protected virtualization this has to change, since the hypervisor needs to read and sometimes also write these pieces of memory. The hypervisor is supposed to poke the classic notifiers, if these are used, out of band with regards to ccw I/O. So these need to be allocated as DMA memory (which is shared memory for protected virtualization guests). Let us factor out everything from struct virtio_ccw_device that needs to be DMA memory in a satellite that is allocated as such. Note: The control blocks of I/O instructions do not need to be shared. These are marshalled by the ultravisor. Signed-off-by: Halil Pasic Reviewed-by: Pierre Morel Reviewed-by: Cornelia Huck Reviewed-by: Michael Mueller Tested-by: Michael Mueller Signed-off-by: Heiko Carstens Acked-by: Petr Tesarik --- drivers/s390/virtio/virtio_ccw.c | 169 ++++++++++++++++++++------------------- 1 file changed, 89 insertions(+), 80 deletions(-) --- a/drivers/s390/virtio/virtio_ccw.c +++ b/drivers/s390/virtio/virtio_ccw.c @@ -49,9 +49,15 @@ struct vq_config_block { #define VIRTIO_CCW_CONFIG_SIZE 0x100 /* same as PCI config space size, should be enough for all drivers */ +struct vcdev_dma_area { + unsigned long indicators; + unsigned long indicators2; + struct vq_config_block config_block; + __u8 status; +}; + struct virtio_ccw_device { struct virtio_device vdev; - __u8 *status; __u8 config[VIRTIO_CCW_CONFIG_SIZE]; struct ccw_device *cdev; __u32 curr_io; @@ -61,24 +67,22 @@ struct virtio_ccw_device { spinlock_t lock; struct mutex io_lock; /* Serializes I/O requests */ struct list_head virtqueues; - unsigned long indicators; - unsigned long indicators2; - struct vq_config_block *config_block; bool is_thinint; bool going_away; bool device_lost; unsigned int config_ready; void *airq_info; + struct vcdev_dma_area *dma_area; }; static inline unsigned long *indicators(struct virtio_ccw_device *vcdev) { - return &vcdev->indicators; + return &vcdev->dma_area->indicators; } static inline unsigned long *indicators2(struct virtio_ccw_device *vcdev) { - return &vcdev->indicators2; + return &vcdev->dma_area->indicators2; } struct vq_info_block_legacy { @@ -339,8 +343,8 @@ static void virtio_ccw_drop_indicator(st struct airq_info *airq_info = vcdev->airq_info; if (vcdev->is_thinint) { - thinint_area = kzalloc(sizeof(*thinint_area), - GFP_DMA | GFP_KERNEL); + thinint_area = ccw_device_dma_zalloc(vcdev->cdev, + sizeof(*thinint_area)); if (!thinint_area) return; thinint_area->summary_indicator = @@ -351,8 +355,8 @@ static void virtio_ccw_drop_indicator(st ccw->cda = (__u32)(unsigned long) thinint_area; } else { /* payload is the address of the indicators */ - indicatorp = kmalloc(sizeof(indicators(vcdev)), - GFP_DMA | GFP_KERNEL); + indicatorp = ccw_device_dma_zalloc(vcdev->cdev, + sizeof(indicators(vcdev))); if (!indicatorp) return; *indicatorp = 0; @@ -372,8 +376,8 @@ static void virtio_ccw_drop_indicator(st "Failed to deregister indicators (%d)\n", ret); else if (vcdev->is_thinint) virtio_ccw_drop_indicators(vcdev); - kfree(indicatorp); - kfree(thinint_area); + ccw_device_dma_free(vcdev->cdev, indicatorp, sizeof(indicators(vcdev))); + ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area)); } static inline long __do_kvm_notify(struct subchannel_id schid, @@ -420,15 +424,15 @@ static int virtio_ccw_read_vq_conf(struc { int ret; - vcdev->config_block->index = index; + vcdev->dma_area->config_block.index = index; ccw->cmd_code = CCW_CMD_READ_VQ_CONF; ccw->flags = 0; ccw->count = sizeof(struct vq_config_block); - ccw->cda = (__u32)(unsigned long)(vcdev->config_block); + ccw->cda = (__u32)(unsigned long)(&vcdev->dma_area->config_block); ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF); if (ret) return ret; - return vcdev->config_block->num ?: -ENOENT; + return vcdev->dma_area->config_block.num ?: -ENOENT; } static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw) @@ -473,7 +477,8 @@ static void virtio_ccw_del_vq(struct vir ret, index); vring_del_virtqueue(vq); - kfree(info->info_block); + ccw_device_dma_free(vcdev->cdev, info->info_block, + sizeof(*info->info_block)); kfree(info); } @@ -483,7 +488,7 @@ static void virtio_ccw_del_vqs(struct vi struct ccw1 *ccw; struct virtio_ccw_device *vcdev = to_vc_device(vdev); - ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL); + ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw)); if (!ccw) return; @@ -492,7 +497,7 @@ static void virtio_ccw_del_vqs(struct vi list_for_each_entry_safe(vq, n, &vdev->vqs, list) virtio_ccw_del_vq(vq, ccw); - kfree(ccw); + ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw)); } static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev, @@ -515,8 +520,8 @@ static struct virtqueue *virtio_ccw_setu err = -ENOMEM; goto out_err; } - info->info_block = kzalloc(sizeof(*info->info_block), - GFP_DMA | GFP_KERNEL); + info->info_block = ccw_device_dma_zalloc(vcdev->cdev, + sizeof(*info->info_block)); if (!info->info_block) { dev_warn(&vcdev->cdev->dev, "no info block\n"); err = -ENOMEM; @@ -580,7 +585,8 @@ out_err: if (vq) vring_del_virtqueue(vq); if (info) { - kfree(info->info_block); + ccw_device_dma_free(vcdev->cdev, info->info_block, + sizeof(*info->info_block)); } kfree(info); return ERR_PTR(err); @@ -594,7 +600,8 @@ static int virtio_ccw_register_adapter_i struct virtio_thinint_area *thinint_area = NULL; struct airq_info *info; - thinint_area = kzalloc(sizeof(*thinint_area), GFP_DMA | GFP_KERNEL); + thinint_area = ccw_device_dma_zalloc(vcdev->cdev, + sizeof(*thinint_area)); if (!thinint_area) { ret = -ENOMEM; goto out; @@ -630,7 +637,7 @@ static int virtio_ccw_register_adapter_i virtio_ccw_drop_indicators(vcdev); } out: - kfree(thinint_area); + ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area)); return ret; } @@ -646,7 +653,7 @@ static int virtio_ccw_find_vqs(struct vi int ret, i; struct ccw1 *ccw; - ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL); + ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw)); if (!ccw) return -ENOMEM; @@ -664,7 +671,8 @@ static int virtio_ccw_find_vqs(struct vi * We need a data area under 2G to communicate. Our payload is * the address of the indicators. */ - indicatorp = kmalloc(sizeof(indicators(vcdev)), GFP_DMA | GFP_KERNEL); + indicatorp = ccw_device_dma_zalloc(vcdev->cdev, + sizeof(indicators(vcdev))); if (!indicatorp) goto out; *indicatorp = (unsigned long) indicators(vcdev); @@ -696,12 +704,16 @@ static int virtio_ccw_find_vqs(struct vi if (ret) goto out; - kfree(indicatorp); - kfree(ccw); + if (indicatorp) + ccw_device_dma_free(vcdev->cdev, indicatorp, + sizeof(indicators(vcdev))); + ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw)); return 0; out: - kfree(indicatorp); - kfree(ccw); + if (indicatorp) + ccw_device_dma_free(vcdev->cdev, indicatorp, + sizeof(indicators(vcdev))); + ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw)); virtio_ccw_del_vqs(vdev); return ret; } @@ -711,12 +723,12 @@ static void virtio_ccw_reset(struct virt struct virtio_ccw_device *vcdev = to_vc_device(vdev); struct ccw1 *ccw; - ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL); + ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw)); if (!ccw) return; /* Zero status bits. */ - *vcdev->status = 0; + vcdev->dma_area->status = 0; /* Send a reset ccw on device. */ ccw->cmd_code = CCW_CMD_VDEV_RESET; @@ -724,7 +736,7 @@ static void virtio_ccw_reset(struct virt ccw->count = 0; ccw->cda = 0; ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET); - kfree(ccw); + ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw)); } static u64 virtio_ccw_get_features(struct virtio_device *vdev) @@ -735,11 +747,11 @@ static u64 virtio_ccw_get_features(struc u64 rc; struct ccw1 *ccw; - ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL); + ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw)); if (!ccw) return 0; - features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL); + features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features)); if (!features) { rc = 0; goto out_free; @@ -772,8 +784,8 @@ static u64 virtio_ccw_get_features(struc rc |= (u64)le32_to_cpu(features->features) << 32; out_free: - kfree(features); - kfree(ccw); + ccw_device_dma_free(vcdev->cdev, features, sizeof(*features)); + ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw)); return rc; } @@ -791,11 +803,11 @@ static int virtio_ccw_finalize_features( return -EINVAL; } - ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL); + ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw)); if (!ccw) return -ENOMEM; - features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL); + features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features)); if (!features) { ret = -ENOMEM; goto out_free; @@ -827,8 +839,8 @@ static int virtio_ccw_finalize_features( ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT); out_free: - kfree(features); - kfree(ccw); + ccw_device_dma_free(vcdev->cdev, features, sizeof(*features)); + ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw)); return ret; } @@ -842,11 +854,12 @@ static void virtio_ccw_get_config(struct void *config_area; unsigned long flags; - ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL); + ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw)); if (!ccw) return; - config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL); + config_area = ccw_device_dma_zalloc(vcdev->cdev, + VIRTIO_CCW_CONFIG_SIZE); if (!config_area) goto out_free; @@ -868,8 +881,8 @@ static void virtio_ccw_get_config(struct memcpy(buf, config_area + offset, len); out_free: - kfree(config_area); - kfree(ccw); + ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE); + ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw)); } static void virtio_ccw_set_config(struct virtio_device *vdev, @@ -881,11 +894,12 @@ static void virtio_ccw_set_config(struct void *config_area; unsigned long flags; - ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL); + ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw)); if (!ccw) return; - config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL); + config_area = ccw_device_dma_zalloc(vcdev->cdev, + VIRTIO_CCW_CONFIG_SIZE); if (!config_area) goto out_free; @@ -904,61 +918,61 @@ static void virtio_ccw_set_config(struct ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG); out_free: - kfree(config_area); - kfree(ccw); + ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE); + ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw)); } static u8 virtio_ccw_get_status(struct virtio_device *vdev) { struct virtio_ccw_device *vcdev = to_vc_device(vdev); - u8 old_status = *vcdev->status; + u8 old_status = vcdev->dma_area->status; struct ccw1 *ccw; if (vcdev->revision < 1) - return *vcdev->status; + return vcdev->dma_area->status; - ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL); + ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw)); if (!ccw) return old_status; ccw->cmd_code = CCW_CMD_READ_STATUS; ccw->flags = 0; - ccw->count = sizeof(*vcdev->status); - ccw->cda = (__u32)(unsigned long)vcdev->status; + ccw->count = sizeof(vcdev->dma_area->status); + ccw->cda = (__u32)(unsigned long)&vcdev->dma_area->status; ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS); /* * If the channel program failed (should only happen if the device * was hotunplugged, and then we clean up via the machine check - * handler anyway), vcdev->status was not overwritten and we just + * handler anyway), vcdev->dma_area->status was not overwritten and we just * return the old status, which is fine. */ - kfree(ccw); + ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw)); - return *vcdev->status; + return vcdev->dma_area->status; } static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status) { struct virtio_ccw_device *vcdev = to_vc_device(vdev); - u8 old_status = *vcdev->status; + u8 old_status = vcdev->dma_area->status; struct ccw1 *ccw; int ret; - ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL); + ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw)); if (!ccw) return; /* Write the status to the host. */ - *vcdev->status = status; + vcdev->dma_area->status = status; ccw->cmd_code = CCW_CMD_WRITE_STATUS; ccw->flags = 0; ccw->count = sizeof(status); - ccw->cda = (__u32)(unsigned long)vcdev->status; + ccw->cda = (__u32)(unsigned long)&vcdev->dma_area->status; ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS); /* Write failed? We assume status is unchanged. */ if (ret) - *vcdev->status = old_status; - kfree(ccw); + vcdev->dma_area->status = old_status; + ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw)); } static const struct virtio_config_ops virtio_ccw_config_ops = { @@ -983,8 +997,8 @@ static void virtio_ccw_release_dev(struc struct virtio_device *dev = dev_to_virtio(_d); struct virtio_ccw_device *vcdev = to_vc_device(dev); - kfree(vcdev->status); - kfree(vcdev->config_block); + ccw_device_dma_free(vcdev->cdev, vcdev->dma_area, + sizeof(*vcdev->dma_area)); kfree(vcdev); } @@ -1192,12 +1206,12 @@ static int virtio_ccw_set_transport_rev( struct ccw1 *ccw; int ret; - ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL); + ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw)); if (!ccw) return -ENOMEM; - rev = kzalloc(sizeof(*rev), GFP_DMA | GFP_KERNEL); + rev = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*rev)); if (!rev) { - kfree(ccw); + ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw)); return -ENOMEM; } @@ -1227,8 +1241,8 @@ static int virtio_ccw_set_transport_rev( } } while (ret == -EOPNOTSUPP); - kfree(ccw); - kfree(rev); + ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw)); + ccw_device_dma_free(vcdev->cdev, rev, sizeof(*rev)); return ret; } @@ -1245,14 +1259,10 @@ static int virtio_ccw_online(struct ccw_ goto out_free; } vcdev->vdev.dev.parent = &cdev->dev; - vcdev->config_block = kzalloc(sizeof(*vcdev->config_block), - GFP_DMA | GFP_KERNEL); - if (!vcdev->config_block) { - ret = -ENOMEM; - goto out_free; - } - vcdev->status = kzalloc(sizeof(*vcdev->status), GFP_DMA | GFP_KERNEL); - if (!vcdev->status) { + vcdev->cdev = cdev; + vcdev->dma_area = ccw_device_dma_zalloc(vcdev->cdev, + sizeof(*vcdev->dma_area)); + if (!vcdev->dma_area) { ret = -ENOMEM; goto out_free; } @@ -1261,7 +1271,6 @@ static int virtio_ccw_online(struct ccw_ vcdev->vdev.dev.release = virtio_ccw_release_dev; vcdev->vdev.config = &virtio_ccw_config_ops; - vcdev->cdev = cdev; init_waitqueue_head(&vcdev->wait_q); INIT_LIST_HEAD(&vcdev->virtqueues); spin_lock_init(&vcdev->lock); @@ -1292,8 +1301,8 @@ out_put: return ret; out_free: if (vcdev) { - kfree(vcdev->status); - kfree(vcdev->config_block); + ccw_device_dma_free(vcdev->cdev, vcdev->dma_area, + sizeof(*vcdev->dma_area)); } kfree(vcdev); return ret;