Jason Wang
2022-Nov-22 03:32 UTC
[RFC PATCH net-next 15/19] pds_vdpa: virtio bar setup for vdpa
? 2022/11/19 06:56, Shannon Nelson ??:> The PDS vDPA device has a virtio BAR for describing itself, and > the pds_vdpa driver needs to access it. Here we copy liberally > from the existing drivers/virtio/virtio_pci_modern_dev.c as it > has what we need, but we need to modify it so that it can work > with our device id and so we can use our own DMA mask. > > We suspect there is room for discussion here about making the > existing code a little more flexible, but we thought we'd at > least start the discussion here.Exactly, since the virtio_pci_modern_dev.c is a library, we could tweak it to allow the caller to pass the device_id with the DMA mask. Then we can avoid code/bug duplication here. Thanks> > Signed-off-by: Shannon Nelson <snelson at pensando.io> > --- > drivers/vdpa/pds/Makefile | 3 +- > drivers/vdpa/pds/pci_drv.c | 10 ++ > drivers/vdpa/pds/pci_drv.h | 2 + > drivers/vdpa/pds/virtio_pci.c | 283 ++++++++++++++++++++++++++++++++++ > 4 files changed, 297 insertions(+), 1 deletion(-) > create mode 100644 drivers/vdpa/pds/virtio_pci.c > > diff --git a/drivers/vdpa/pds/Makefile b/drivers/vdpa/pds/Makefile > index 3ba28a875574..b8376ab165bc 100644 > --- a/drivers/vdpa/pds/Makefile > +++ b/drivers/vdpa/pds/Makefile > @@ -4,4 +4,5 @@ > obj-$(CONFIG_PDS_VDPA) := pds_vdpa.o > > pds_vdpa-y := pci_drv.o \ > - debugfs.o > + debugfs.o \ > + virtio_pci.o > diff --git a/drivers/vdpa/pds/pci_drv.c b/drivers/vdpa/pds/pci_drv.c > index 369e11153f21..10491e22778c 100644 > --- a/drivers/vdpa/pds/pci_drv.c > +++ b/drivers/vdpa/pds/pci_drv.c > @@ -44,6 +44,14 @@ pds_vdpa_pci_probe(struct pci_dev *pdev, > goto err_out_free_mem; > } > > + vdpa_pdev->vd_mdev.pci_dev = pdev; > + err = pds_vdpa_probe_virtio(&vdpa_pdev->vd_mdev); > + if (err) { > + dev_err(dev, "Unable to probe for virtio configuration: %pe\n", > + ERR_PTR(err)); > + goto err_out_free_mem; > + } > + > pci_enable_pcie_error_reporting(pdev); > > /* Use devres management */ > @@ -74,6 +82,7 @@ pds_vdpa_pci_probe(struct pci_dev *pdev, > err_out_pci_release_device: > pci_disable_device(pdev); > err_out_free_mem: > + pds_vdpa_remove_virtio(&vdpa_pdev->vd_mdev); > pci_disable_pcie_error_reporting(pdev); > kfree(vdpa_pdev); > return err; > @@ -88,6 +97,7 @@ pds_vdpa_pci_remove(struct pci_dev *pdev) > pci_clear_master(pdev); > pci_disable_pcie_error_reporting(pdev); > pci_disable_device(pdev); > + pds_vdpa_remove_virtio(&vdpa_pdev->vd_mdev); > kfree(vdpa_pdev); > > dev_info(&pdev->dev, "Removed\n"); > diff --git a/drivers/vdpa/pds/pci_drv.h b/drivers/vdpa/pds/pci_drv.h > index 747809e0df9e..15f3b34fafa9 100644 > --- a/drivers/vdpa/pds/pci_drv.h > +++ b/drivers/vdpa/pds/pci_drv.h > @@ -43,4 +43,6 @@ struct pds_vdpa_pci_device { > struct virtio_pci_modern_device vd_mdev; > }; > > +int pds_vdpa_probe_virtio(struct virtio_pci_modern_device *mdev); > +void pds_vdpa_remove_virtio(struct virtio_pci_modern_device *mdev); > #endif /* _PCI_DRV_H */ > diff --git a/drivers/vdpa/pds/virtio_pci.c b/drivers/vdpa/pds/virtio_pci.c > new file mode 100644 > index 000000000000..0f4ac9467199 > --- /dev/null > +++ b/drivers/vdpa/pds/virtio_pci.c > @@ -0,0 +1,283 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > + > +/* > + * adapted from drivers/virtio/virtio_pci_modern_dev.c, v6.0-rc1 > + */ > + > +#include <linux/virtio_pci_modern.h> > +#include <linux/module.h> > +#include <linux/pci.h> > +#include <linux/delay.h> > + > +#include "pci_drv.h" > + > +/* > + * pds_vdpa_map_capability - map a part of virtio pci capability > + * @mdev: the modern virtio-pci device > + * @off: offset of the capability > + * @minlen: minimal length of the capability > + * @align: align requirement > + * @start: start from the capability > + * @size: map size > + * @len: the length that is actually mapped > + * @pa: physical address of the capability > + * > + * Returns the io address of for the part of the capability > + */ > +static void __iomem * > +pds_vdpa_map_capability(struct virtio_pci_modern_device *mdev, int off, > + size_t minlen, u32 align, u32 start, u32 size, > + size_t *len, resource_size_t *pa) > +{ > + struct pci_dev *dev = mdev->pci_dev; > + u8 bar; > + u32 offset, length; > + void __iomem *p; > + > + pci_read_config_byte(dev, off + offsetof(struct virtio_pci_cap, > + bar), > + &bar); > + pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, offset), > + &offset); > + pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, length), > + &length); > + > + /* Check if the BAR may have changed since we requested the region. */ > + if (bar >= PCI_STD_NUM_BARS || !(mdev->modern_bars & (1 << bar))) { > + dev_err(&dev->dev, > + "virtio_pci: bar unexpectedly changed to %u\n", bar); > + return NULL; > + } > + > + if (length <= start) { > + dev_err(&dev->dev, > + "virtio_pci: bad capability len %u (>%u expected)\n", > + length, start); > + return NULL; > + } > + > + if (length - start < minlen) { > + dev_err(&dev->dev, > + "virtio_pci: bad capability len %u (>=%zu expected)\n", > + length, minlen); > + return NULL; > + } > + > + length -= start; > + > + if (start + offset < offset) { > + dev_err(&dev->dev, > + "virtio_pci: map wrap-around %u+%u\n", > + start, offset); > + return NULL; > + } > + > + offset += start; > + > + if (offset & (align - 1)) { > + dev_err(&dev->dev, > + "virtio_pci: offset %u not aligned to %u\n", > + offset, align); > + return NULL; > + } > + > + if (length > size) > + length = size; > + > + if (len) > + *len = length; > + > + if (minlen + offset < minlen || > + minlen + offset > pci_resource_len(dev, bar)) { > + dev_err(&dev->dev, > + "virtio_pci: map virtio %zu@%u out of range on bar %i length %lu\n", > + minlen, offset, > + bar, (unsigned long)pci_resource_len(dev, bar)); > + return NULL; > + } > + > + p = pci_iomap_range(dev, bar, offset, length); > + if (!p) > + dev_err(&dev->dev, > + "virtio_pci: unable to map virtio %u@%u on bar %i\n", > + length, offset, bar); > + else if (pa) > + *pa = pci_resource_start(dev, bar) + offset; > + > + return p; > +} > + > +/** > + * virtio_pci_find_capability - walk capabilities to find device info. > + * @dev: the pci device > + * @cfg_type: the VIRTIO_PCI_CAP_* value we seek > + * @ioresource_types: IORESOURCE_MEM and/or IORESOURCE_IO. > + * @bars: the bitmask of BARs > + * > + * Returns offset of the capability, or 0. > + */ > +static inline int virtio_pci_find_capability(struct pci_dev *dev, u8 cfg_type, > + u32 ioresource_types, int *bars) > +{ > + int pos; > + > + for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR); > + pos > 0; > + pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) { > + u8 type, bar; > + > + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, > + cfg_type), > + &type); > + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, > + bar), > + &bar); > + > + /* Ignore structures with reserved BAR values */ > + if (bar >= PCI_STD_NUM_BARS) > + continue; > + > + if (type == cfg_type) { > + if (pci_resource_len(dev, bar) && > + pci_resource_flags(dev, bar) & ioresource_types) { > + *bars |= (1 << bar); > + return pos; > + } > + } > + } > + return 0; > +} > + > +/* > + * pds_vdpa_probe_virtio: probe the modern virtio pci device, note that the > + * caller is required to enable PCI device before calling this function. > + * @mdev: the modern virtio-pci device > + * > + * Return 0 on succeed otherwise fail > + */ > +int pds_vdpa_probe_virtio(struct virtio_pci_modern_device *mdev) > +{ > + struct pci_dev *pci_dev = mdev->pci_dev; > + int err, common, isr, notify, device; > + u32 notify_length; > + u32 notify_offset; > + > + /* check for a common config: if not, use legacy mode (bar 0). */ > + common = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG, > + IORESOURCE_IO | IORESOURCE_MEM, > + &mdev->modern_bars); > + if (!common) { > + dev_info(&pci_dev->dev, > + "virtio_pci: missing common config\n"); > + return -ENODEV; > + } > + > + /* If common is there, these should be too... */ > + isr = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_ISR_CFG, > + IORESOURCE_IO | IORESOURCE_MEM, > + &mdev->modern_bars); > + notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG, > + IORESOURCE_IO | IORESOURCE_MEM, > + &mdev->modern_bars); > + if (!isr || !notify) { > + dev_err(&pci_dev->dev, > + "virtio_pci: missing capabilities %i/%i/%i\n", > + common, isr, notify); > + return -EINVAL; > + } > + > + /* Device capability is only mandatory for devices that have > + * device-specific configuration. > + */ > + device = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG, > + IORESOURCE_IO | IORESOURCE_MEM, > + &mdev->modern_bars); > + > + err = pci_request_selected_regions(pci_dev, mdev->modern_bars, > + "virtio-pci-modern"); > + if (err) > + return err; > + > + err = -EINVAL; > + mdev->common = pds_vdpa_map_capability(mdev, common, > + sizeof(struct virtio_pci_common_cfg), 4, > + 0, sizeof(struct virtio_pci_common_cfg), > + NULL, NULL); > + if (!mdev->common) > + goto err_map_common; > + mdev->isr = pds_vdpa_map_capability(mdev, isr, sizeof(u8), 1, > + 0, 1, > + NULL, NULL); > + if (!mdev->isr) > + goto err_map_isr; > + > + /* Read notify_off_multiplier from config space. */ > + pci_read_config_dword(pci_dev, > + notify + offsetof(struct virtio_pci_notify_cap, > + notify_off_multiplier), > + &mdev->notify_offset_multiplier); > + /* Read notify length and offset from config space. */ > + pci_read_config_dword(pci_dev, > + notify + offsetof(struct virtio_pci_notify_cap, > + cap.length), > + ¬ify_length); > + > + pci_read_config_dword(pci_dev, > + notify + offsetof(struct virtio_pci_notify_cap, > + cap.offset), > + ¬ify_offset); > + > + /* We don't know how many VQs we'll map, ahead of the time. > + * If notify length is small, map it all now. > + * Otherwise, map each VQ individually later. > + */ > + if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) { > + mdev->notify_base = pds_vdpa_map_capability(mdev, notify, > + 2, 2, > + 0, notify_length, > + &mdev->notify_len, > + &mdev->notify_pa); > + if (!mdev->notify_base) > + goto err_map_notify; > + } else { > + mdev->notify_map_cap = notify; > + } > + > + /* Again, we don't know how much we should map, but PAGE_SIZE > + * is more than enough for all existing devices. > + */ > + if (device) { > + mdev->device = pds_vdpa_map_capability(mdev, device, 0, 4, > + 0, PAGE_SIZE, > + &mdev->device_len, > + NULL); > + if (!mdev->device) > + goto err_map_device; > + } > + > + return 0; > + > +err_map_device: > + if (mdev->notify_base) > + pci_iounmap(pci_dev, mdev->notify_base); > +err_map_notify: > + pci_iounmap(pci_dev, mdev->isr); > +err_map_isr: > + pci_iounmap(pci_dev, mdev->common); > +err_map_common: > + pci_release_selected_regions(pci_dev, mdev->modern_bars); > + return err; > +} > + > +void pds_vdpa_remove_virtio(struct virtio_pci_modern_device *mdev) > +{ > + struct pci_dev *pci_dev = mdev->pci_dev; > + > + if (mdev->device) > + pci_iounmap(pci_dev, mdev->device); > + if (mdev->notify_base) > + pci_iounmap(pci_dev, mdev->notify_base); > + pci_iounmap(pci_dev, mdev->isr); > + pci_iounmap(pci_dev, mdev->common); > + pci_release_selected_regions(pci_dev, mdev->modern_bars); > +}
Jason Wang
2022-Nov-22 06:36 UTC
[RFC PATCH net-next 15/19] pds_vdpa: virtio bar setup for vdpa
On Tue, Nov 22, 2022 at 11:32 AM Jason Wang <jasowang at redhat.com> wrote:> > > ? 2022/11/19 06:56, Shannon Nelson ??: > > The PDS vDPA device has a virtio BAR for describing itself, and > > the pds_vdpa driver needs to access it. Here we copy liberally > > from the existing drivers/virtio/virtio_pci_modern_dev.c as it > > has what we need, but we need to modify it so that it can work > > with our device id and so we can use our own DMA mask. > > > > We suspect there is room for discussion here about making the > > existing code a little more flexible, but we thought we'd at > > least start the discussion here. > > > Exactly, since the virtio_pci_modern_dev.c is a library, we could tweak > it to allow the caller to pass the device_id with the DMA mask. Then we > can avoid code/bug duplication here.Btw, I found only isr/notification were used but not the others? If this is true, we can avoid mapping those capabilities. Thanks> > Thanks > > > > > > Signed-off-by: Shannon Nelson <snelson at pensando.io> > > --- > > drivers/vdpa/pds/Makefile | 3 +- > > drivers/vdpa/pds/pci_drv.c | 10 ++ > > drivers/vdpa/pds/pci_drv.h | 2 + > > drivers/vdpa/pds/virtio_pci.c | 283 ++++++++++++++++++++++++++++++++++ > > 4 files changed, 297 insertions(+), 1 deletion(-) > > create mode 100644 drivers/vdpa/pds/virtio_pci.c > > > > diff --git a/drivers/vdpa/pds/Makefile b/drivers/vdpa/pds/Makefile > > index 3ba28a875574..b8376ab165bc 100644 > > --- a/drivers/vdpa/pds/Makefile > > +++ b/drivers/vdpa/pds/Makefile > > @@ -4,4 +4,5 @@ > > obj-$(CONFIG_PDS_VDPA) := pds_vdpa.o > > > > pds_vdpa-y := pci_drv.o \ > > - debugfs.o > > + debugfs.o \ > > + virtio_pci.o > > diff --git a/drivers/vdpa/pds/pci_drv.c b/drivers/vdpa/pds/pci_drv.c > > index 369e11153f21..10491e22778c 100644 > > --- a/drivers/vdpa/pds/pci_drv.c > > +++ b/drivers/vdpa/pds/pci_drv.c > > @@ -44,6 +44,14 @@ pds_vdpa_pci_probe(struct pci_dev *pdev, > > goto err_out_free_mem; > > } > > > > + vdpa_pdev->vd_mdev.pci_dev = pdev; > > + err = pds_vdpa_probe_virtio(&vdpa_pdev->vd_mdev); > > + if (err) { > > + dev_err(dev, "Unable to probe for virtio configuration: %pe\n", > > + ERR_PTR(err)); > > + goto err_out_free_mem; > > + } > > + > > pci_enable_pcie_error_reporting(pdev); > > > > /* Use devres management */ > > @@ -74,6 +82,7 @@ pds_vdpa_pci_probe(struct pci_dev *pdev, > > err_out_pci_release_device: > > pci_disable_device(pdev); > > err_out_free_mem: > > + pds_vdpa_remove_virtio(&vdpa_pdev->vd_mdev); > > pci_disable_pcie_error_reporting(pdev); > > kfree(vdpa_pdev); > > return err; > > @@ -88,6 +97,7 @@ pds_vdpa_pci_remove(struct pci_dev *pdev) > > pci_clear_master(pdev); > > pci_disable_pcie_error_reporting(pdev); > > pci_disable_device(pdev); > > + pds_vdpa_remove_virtio(&vdpa_pdev->vd_mdev); > > kfree(vdpa_pdev); > > > > dev_info(&pdev->dev, "Removed\n"); > > diff --git a/drivers/vdpa/pds/pci_drv.h b/drivers/vdpa/pds/pci_drv.h > > index 747809e0df9e..15f3b34fafa9 100644 > > --- a/drivers/vdpa/pds/pci_drv.h > > +++ b/drivers/vdpa/pds/pci_drv.h > > @@ -43,4 +43,6 @@ struct pds_vdpa_pci_device { > > struct virtio_pci_modern_device vd_mdev; > > }; > > > > +int pds_vdpa_probe_virtio(struct virtio_pci_modern_device *mdev); > > +void pds_vdpa_remove_virtio(struct virtio_pci_modern_device *mdev); > > #endif /* _PCI_DRV_H */ > > diff --git a/drivers/vdpa/pds/virtio_pci.c b/drivers/vdpa/pds/virtio_pci.c > > new file mode 100644 > > index 000000000000..0f4ac9467199 > > --- /dev/null > > +++ b/drivers/vdpa/pds/virtio_pci.c > > @@ -0,0 +1,283 @@ > > +// SPDX-License-Identifier: GPL-2.0-or-later > > + > > +/* > > + * adapted from drivers/virtio/virtio_pci_modern_dev.c, v6.0-rc1 > > + */ > > + > > +#include <linux/virtio_pci_modern.h> > > +#include <linux/module.h> > > +#include <linux/pci.h> > > +#include <linux/delay.h> > > + > > +#include "pci_drv.h" > > + > > +/* > > + * pds_vdpa_map_capability - map a part of virtio pci capability > > + * @mdev: the modern virtio-pci device > > + * @off: offset of the capability > > + * @minlen: minimal length of the capability > > + * @align: align requirement > > + * @start: start from the capability > > + * @size: map size > > + * @len: the length that is actually mapped > > + * @pa: physical address of the capability > > + * > > + * Returns the io address of for the part of the capability > > + */ > > +static void __iomem * > > +pds_vdpa_map_capability(struct virtio_pci_modern_device *mdev, int off, > > + size_t minlen, u32 align, u32 start, u32 size, > > + size_t *len, resource_size_t *pa) > > +{ > > + struct pci_dev *dev = mdev->pci_dev; > > + u8 bar; > > + u32 offset, length; > > + void __iomem *p; > > + > > + pci_read_config_byte(dev, off + offsetof(struct virtio_pci_cap, > > + bar), > > + &bar); > > + pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, offset), > > + &offset); > > + pci_read_config_dword(dev, off + offsetof(struct virtio_pci_cap, length), > > + &length); > > + > > + /* Check if the BAR may have changed since we requested the region. */ > > + if (bar >= PCI_STD_NUM_BARS || !(mdev->modern_bars & (1 << bar))) { > > + dev_err(&dev->dev, > > + "virtio_pci: bar unexpectedly changed to %u\n", bar); > > + return NULL; > > + } > > + > > + if (length <= start) { > > + dev_err(&dev->dev, > > + "virtio_pci: bad capability len %u (>%u expected)\n", > > + length, start); > > + return NULL; > > + } > > + > > + if (length - start < minlen) { > > + dev_err(&dev->dev, > > + "virtio_pci: bad capability len %u (>=%zu expected)\n", > > + length, minlen); > > + return NULL; > > + } > > + > > + length -= start; > > + > > + if (start + offset < offset) { > > + dev_err(&dev->dev, > > + "virtio_pci: map wrap-around %u+%u\n", > > + start, offset); > > + return NULL; > > + } > > + > > + offset += start; > > + > > + if (offset & (align - 1)) { > > + dev_err(&dev->dev, > > + "virtio_pci: offset %u not aligned to %u\n", > > + offset, align); > > + return NULL; > > + } > > + > > + if (length > size) > > + length = size; > > + > > + if (len) > > + *len = length; > > + > > + if (minlen + offset < minlen || > > + minlen + offset > pci_resource_len(dev, bar)) { > > + dev_err(&dev->dev, > > + "virtio_pci: map virtio %zu@%u out of range on bar %i length %lu\n", > > + minlen, offset, > > + bar, (unsigned long)pci_resource_len(dev, bar)); > > + return NULL; > > + } > > + > > + p = pci_iomap_range(dev, bar, offset, length); > > + if (!p) > > + dev_err(&dev->dev, > > + "virtio_pci: unable to map virtio %u@%u on bar %i\n", > > + length, offset, bar); > > + else if (pa) > > + *pa = pci_resource_start(dev, bar) + offset; > > + > > + return p; > > +} > > + > > +/** > > + * virtio_pci_find_capability - walk capabilities to find device info. > > + * @dev: the pci device > > + * @cfg_type: the VIRTIO_PCI_CAP_* value we seek > > + * @ioresource_types: IORESOURCE_MEM and/or IORESOURCE_IO. > > + * @bars: the bitmask of BARs > > + * > > + * Returns offset of the capability, or 0. > > + */ > > +static inline int virtio_pci_find_capability(struct pci_dev *dev, u8 cfg_type, > > + u32 ioresource_types, int *bars) > > +{ > > + int pos; > > + > > + for (pos = pci_find_capability(dev, PCI_CAP_ID_VNDR); > > + pos > 0; > > + pos = pci_find_next_capability(dev, pos, PCI_CAP_ID_VNDR)) { > > + u8 type, bar; > > + > > + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, > > + cfg_type), > > + &type); > > + pci_read_config_byte(dev, pos + offsetof(struct virtio_pci_cap, > > + bar), > > + &bar); > > + > > + /* Ignore structures with reserved BAR values */ > > + if (bar >= PCI_STD_NUM_BARS) > > + continue; > > + > > + if (type == cfg_type) { > > + if (pci_resource_len(dev, bar) && > > + pci_resource_flags(dev, bar) & ioresource_types) { > > + *bars |= (1 << bar); > > + return pos; > > + } > > + } > > + } > > + return 0; > > +} > > + > > +/* > > + * pds_vdpa_probe_virtio: probe the modern virtio pci device, note that the > > + * caller is required to enable PCI device before calling this function. > > + * @mdev: the modern virtio-pci device > > + * > > + * Return 0 on succeed otherwise fail > > + */ > > +int pds_vdpa_probe_virtio(struct virtio_pci_modern_device *mdev) > > +{ > > + struct pci_dev *pci_dev = mdev->pci_dev; > > + int err, common, isr, notify, device; > > + u32 notify_length; > > + u32 notify_offset; > > + > > + /* check for a common config: if not, use legacy mode (bar 0). */ > > + common = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_COMMON_CFG, > > + IORESOURCE_IO | IORESOURCE_MEM, > > + &mdev->modern_bars); > > + if (!common) { > > + dev_info(&pci_dev->dev, > > + "virtio_pci: missing common config\n"); > > + return -ENODEV; > > + } > > + > > + /* If common is there, these should be too... */ > > + isr = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_ISR_CFG, > > + IORESOURCE_IO | IORESOURCE_MEM, > > + &mdev->modern_bars); > > + notify = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_NOTIFY_CFG, > > + IORESOURCE_IO | IORESOURCE_MEM, > > + &mdev->modern_bars); > > + if (!isr || !notify) { > > + dev_err(&pci_dev->dev, > > + "virtio_pci: missing capabilities %i/%i/%i\n", > > + common, isr, notify); > > + return -EINVAL; > > + } > > + > > + /* Device capability is only mandatory for devices that have > > + * device-specific configuration. > > + */ > > + device = virtio_pci_find_capability(pci_dev, VIRTIO_PCI_CAP_DEVICE_CFG, > > + IORESOURCE_IO | IORESOURCE_MEM, > > + &mdev->modern_bars); > > + > > + err = pci_request_selected_regions(pci_dev, mdev->modern_bars, > > + "virtio-pci-modern"); > > + if (err) > > + return err; > > + > > + err = -EINVAL; > > + mdev->common = pds_vdpa_map_capability(mdev, common, > > + sizeof(struct virtio_pci_common_cfg), 4, > > + 0, sizeof(struct virtio_pci_common_cfg), > > + NULL, NULL); > > + if (!mdev->common) > > + goto err_map_common; > > + mdev->isr = pds_vdpa_map_capability(mdev, isr, sizeof(u8), 1, > > + 0, 1, > > + NULL, NULL); > > + if (!mdev->isr) > > + goto err_map_isr; > > + > > + /* Read notify_off_multiplier from config space. */ > > + pci_read_config_dword(pci_dev, > > + notify + offsetof(struct virtio_pci_notify_cap, > > + notify_off_multiplier), > > + &mdev->notify_offset_multiplier); > > + /* Read notify length and offset from config space. */ > > + pci_read_config_dword(pci_dev, > > + notify + offsetof(struct virtio_pci_notify_cap, > > + cap.length), > > + ¬ify_length); > > + > > + pci_read_config_dword(pci_dev, > > + notify + offsetof(struct virtio_pci_notify_cap, > > + cap.offset), > > + ¬ify_offset); > > + > > + /* We don't know how many VQs we'll map, ahead of the time. > > + * If notify length is small, map it all now. > > + * Otherwise, map each VQ individually later. > > + */ > > + if ((u64)notify_length + (notify_offset % PAGE_SIZE) <= PAGE_SIZE) { > > + mdev->notify_base = pds_vdpa_map_capability(mdev, notify, > > + 2, 2, > > + 0, notify_length, > > + &mdev->notify_len, > > + &mdev->notify_pa); > > + if (!mdev->notify_base) > > + goto err_map_notify; > > + } else { > > + mdev->notify_map_cap = notify; > > + } > > + > > + /* Again, we don't know how much we should map, but PAGE_SIZE > > + * is more than enough for all existing devices. > > + */ > > + if (device) { > > + mdev->device = pds_vdpa_map_capability(mdev, device, 0, 4, > > + 0, PAGE_SIZE, > > + &mdev->device_len, > > + NULL); > > + if (!mdev->device) > > + goto err_map_device; > > + } > > + > > + return 0; > > + > > +err_map_device: > > + if (mdev->notify_base) > > + pci_iounmap(pci_dev, mdev->notify_base); > > +err_map_notify: > > + pci_iounmap(pci_dev, mdev->isr); > > +err_map_isr: > > + pci_iounmap(pci_dev, mdev->common); > > +err_map_common: > > + pci_release_selected_regions(pci_dev, mdev->modern_bars); > > + return err; > > +} > > + > > +void pds_vdpa_remove_virtio(struct virtio_pci_modern_device *mdev) > > +{ > > + struct pci_dev *pci_dev = mdev->pci_dev; > > + > > + if (mdev->device) > > + pci_iounmap(pci_dev, mdev->device); > > + if (mdev->notify_base) > > + pci_iounmap(pci_dev, mdev->notify_base); > > + pci_iounmap(pci_dev, mdev->isr); > > + pci_iounmap(pci_dev, mdev->common); > > + pci_release_selected_regions(pci_dev, mdev->modern_bars); > > +}