From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 9D35D2020D33F for ; Tue, 27 Aug 2019 01:37:21 -0700 (PDT) Date: Tue, 27 Aug 2019 10:34:57 +0200 From: Cornelia Huck Subject: Re: [PATCH 04/19] virtio: Implement get_shm_region for PCI transport Message-ID: <20190827103457.35927d9d.cohuck@redhat.com> In-Reply-To: <20190821175720.25901-5-vgoyal@redhat.com> References: <20190821175720.25901-1-vgoyal@redhat.com> <20190821175720.25901-5-vgoyal@redhat.com> MIME-Version: 1.0 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" To: Vivek Goyal Cc: kbuild test robot , kvm@vger.kernel.org, miklos@szeredi.hu, linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org, dgilbert@redhat.com, virtio-fs@redhat.com, Sebastien Boeuf , stefanha@redhat.com, linux-fsdevel@vger.kernel.org List-ID: On Wed, 21 Aug 2019 13:57:05 -0400 Vivek Goyal wrote: > From: Sebastien Boeuf > > On PCI the shm regions are found using capability entries; > find a region by searching for the capability. > > Cc: kvm@vger.kernel.org > Signed-off-by: Sebastien Boeuf > Signed-off-by: Dr. David Alan Gilbert > Signed-off-by: kbuild test robot An s-o-b by a test robot looks a bit odd. > --- > drivers/virtio/virtio_pci_modern.c | 108 +++++++++++++++++++++++++++++ > include/uapi/linux/virtio_pci.h | 11 ++- > 2 files changed, 118 insertions(+), 1 deletion(-) > > diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c > index 7abcc50838b8..1cdedd93f42a 100644 > --- a/drivers/virtio/virtio_pci_modern.c > +++ b/drivers/virtio/virtio_pci_modern.c > @@ -443,6 +443,112 @@ static void del_vq(struct virtio_pci_vq_info *info) > vring_del_virtqueue(vq); > } > > +static int virtio_pci_find_shm_cap(struct pci_dev *dev, > + u8 required_id, > + u8 *bar, u64 *offset, u64 *len) > +{ > + int pos; > + > + for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR); Indentation looks a bit off here. > + pos > 0; > + pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) { > + u8 type, cap_len, id; > + u32 tmp32; Here as well. > + u64 res_offset, res_length; > + > + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, > + cfg_type), > + &type); > + if (type != VIRTIO_PCI_CAP_SHARED_MEMORY_CFG) And here. > + continue; > + > + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, > + cap_len), > + &cap_len); > + if (cap_len != sizeof(struct virtio_pci_cap64)) { > + printk(KERN_ERR "%s: shm cap with bad size offset: %d size: %d\n", > + __func__, pos, cap_len); Probably better to use dev_warn() instead of printk. > + continue; > + } Indentation looks off again (might be a space vs tabs issue; maybe check the whole patch for indentation problems?) > + > + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, > + id), > + &id); > + if (id != required_id) > + continue; > + > + /* Type, and ID match, looks good */ > + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, > + bar), > + bar); > + > + /* Read the lower 32bit of length and offset */ > + pci_read_config_dword(dev, pos + offsetof(struct virtio_pci_cap, offset), > + &tmp32); > + res_offset = tmp32; > + pci_read_config_dword(dev, pos + offsetof(struct virtio_pci_cap, length), > + &tmp32); > + res_length = tmp32; > + > + /* and now the top half */ > + pci_read_config_dword(dev, > + pos + offsetof(struct virtio_pci_cap64, > + offset_hi), > + &tmp32); > + res_offset |= ((u64)tmp32) << 32; > + pci_read_config_dword(dev, > + pos + offsetof(struct virtio_pci_cap64, > + length_hi), > + &tmp32); > + res_length |= ((u64)tmp32) << 32; > + > + *offset = res_offset; > + *len = res_length; > + > + return pos; > + } > + return 0; > +} > + > +static bool vp_get_shm_region(struct virtio_device *vdev, > + struct virtio_shm_region *region, u8 id) > +{ > + struct virtio_pci_device *vp_dev = to_vp_device(vdev); This whole function looks like it is indented incorrectly. > + struct pci_dev *pci_dev = vp_dev->pci_dev; > + u8 bar; > + u64 offset, len; > + phys_addr_t phys_addr; > + size_t bar_len; > + char *bar_name; > + int ret; > + > + if (!virtio_pci_find_shm_cap(pci_dev, id, &bar, &offset, &len)) { > + return false; > + } You can drop the curly braces. > + > + ret = pci_request_region(pci_dev, bar, "virtio-pci-shm"); > + if (ret < 0) { > + dev_err(&pci_dev->dev, "%s: failed to request BAR\n", > + __func__); > + return false; > + } > + > + phys_addr = pci_resource_start(pci_dev, bar); > + bar_len = pci_resource_len(pci_dev, bar); > + > + if (offset + len > bar_len) { > + dev_err(&pci_dev->dev, > + "%s: bar shorter than cap offset+len\n", > + __func__); > + return false; > + } > + > + region->len = len; > + region->addr = (u64) phys_addr + offset; > + > + return true; > +} > + > static const struct virtio_config_ops virtio_pci_config_nodev_ops = { > .get = NULL, > .set = NULL, Apart from the coding style nits, the logic of the patch looks sane to me. (...) As does the rest of the patch. _______________________________________________ Linux-nvdimm mailing list Linux-nvdimm@lists.01.org https://lists.01.org/mailman/listinfo/linux-nvdimm