For vfio-user, device operations such as IRQ handling and region
read/writes are implemented in userspace over the control socket, not
ioctl() or read()/write() to the vfio kernel driver; add an ops vector
to generalize this, and implement vfio_device_io_ops_ioctl for
interacting with the kernel vfio driver.
Originally-by: John Johnson <john.g.johnson@oracle.com>
Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Signed-off-by: John Levon <john.levon@nutanix.com>
---
hw/vfio/ap.c | 2 +-
hw/vfio/ccw.c | 2 +-
hw/vfio/container-base.c | 6 +-
hw/vfio/device.c | 102 ++++++++++++++++++++++++++++++----
hw/vfio/listener.c | 13 +++--
hw/vfio/pci.c | 40 +++++++------
hw/vfio/platform.c | 2 +-
hw/vfio/region.c | 17 ++++--
include/hw/vfio/vfio-device.h | 24 +++++++-
9 files changed, 155 insertions(+), 53 deletions(-)
diff --git a/hw/vfio/ap.c b/hw/vfio/ap.c
index f311bca5b6..b6233b2107 100644
--- a/hw/vfio/ap.c
+++ b/hw/vfio/ap.c
@@ -229,7 +229,7 @@ static void vfio_ap_instance_init(Object *obj)
* handle ram_block_discard_disable().
*/
vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_AP, &vfio_ap_ops,
- DEVICE(vapdev), true);
+ &vfio_device_io_ops_ioctl, DEVICE(vapdev), true);
/* AP device is mdev type device */
vbasedev->mdev = true;
diff --git a/hw/vfio/ccw.c b/hw/vfio/ccw.c
index 14dee7cd19..aee52b5a8d 100644
--- a/hw/vfio/ccw.c
+++ b/hw/vfio/ccw.c
@@ -676,7 +676,7 @@ static void vfio_ccw_instance_init(Object *obj)
* ram_block_discard_disable().
*/
vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_CCW, &vfio_ccw_ops,
- DEVICE(vcdev), true);
+ &vfio_device_io_ops_ioctl, DEVICE(vcdev), true);
}
#ifdef CONFIG_IOMMUFD
diff --git a/hw/vfio/container-base.c b/hw/vfio/container-base.c
index 613fe1a00d..16fe5f79d2 100644
--- a/hw/vfio/container-base.c
+++ b/hw/vfio/container-base.c
@@ -198,11 +198,7 @@ static int vfio_device_dma_logging_report(VFIODevice *vbasedev, hwaddr iova,
feature->flags = VFIO_DEVICE_FEATURE_GET |
VFIO_DEVICE_FEATURE_DMA_LOGGING_REPORT;
- if (ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature)) {
- return -errno;
- }
-
- return 0;
+ return vbasedev->io_ops->device_feature(vbasedev, feature);
}
static int vfio_container_iommu_query_dirty_bitmap(const VFIOContainerBase *bcontainer,
diff --git a/hw/vfio/device.c b/hw/vfio/device.c
index 102fa5a9b4..545d9f1faf 100644
--- a/hw/vfio/device.c
+++ b/hw/vfio/device.c
@@ -82,7 +82,7 @@ void vfio_device_irq_disable(VFIODevice *vbasedev, int index)
.count = 0,
};
- ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
+ vbasedev->io_ops->set_irqs(vbasedev, &irq_set);
}
void vfio_device_irq_unmask(VFIODevice *vbasedev, int index)
@@ -95,7 +95,7 @@ void vfio_device_irq_unmask(VFIODevice *vbasedev, int index)
.count = 1,
};
- ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
+ vbasedev->io_ops->set_irqs(vbasedev, &irq_set);
}
void vfio_device_irq_mask(VFIODevice *vbasedev, int index)
@@ -108,7 +108,7 @@ void vfio_device_irq_mask(VFIODevice *vbasedev, int index)
.count = 1,
};
- ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
+ vbasedev->io_ops->set_irqs(vbasedev, &irq_set);
}
static inline const char *action_to_str(int action)
@@ -155,6 +155,7 @@ bool vfio_device_irq_set_signaling(VFIODevice *vbasedev, int index, int subindex
int argsz;
const char *name;
int32_t *pfd;
+ int ret;
argsz = sizeof(*irq_set) + sizeof(*pfd);
@@ -167,7 +168,9 @@ bool vfio_device_irq_set_signaling(VFIODevice *vbasedev, int index, int subindex
pfd = (int32_t *)&irq_set->data;
*pfd = fd;
- if (!ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, irq_set)) {
+ ret = vbasedev->io_ops->set_irqs(vbasedev, irq_set);
+
+ if (!ret) {
return true;
}
@@ -188,22 +191,19 @@ bool vfio_device_irq_set_signaling(VFIODevice *vbasedev, int index, int subindex
int vfio_device_get_irq_info(VFIODevice *vbasedev, int index,
struct vfio_irq_info *info)
{
- int ret;
-
memset(info, 0, sizeof(*info));
info->argsz = sizeof(*info);
info->index = index;
- ret = ioctl(vbasedev->fd, VFIO_DEVICE_GET_IRQ_INFO, info);
-
- return ret < 0 ? -errno : ret;
+ return vbasedev->io_ops->get_irq_info(vbasedev, info);
}
int vfio_device_get_region_info(VFIODevice *vbasedev, int index,
struct vfio_region_info **info)
{
size_t argsz = sizeof(struct vfio_region_info);
+ int ret;
/* create region info cache */
if (vbasedev->reginfo == NULL) {
@@ -222,10 +222,11 @@ int vfio_device_get_region_info(VFIODevice *vbasedev, int index,
retry:
(*info)->argsz = argsz;
- if (ioctl(vbasedev->fd, VFIO_DEVICE_GET_REGION_INFO, *info)) {
+ ret = vbasedev->io_ops->get_region_info(vbasedev, *info);
+ if (ret != 0) {
g_free(*info);
*info = NULL;
- return -errno;
+ return ret;
}
if ((*info)->argsz > argsz) {
@@ -332,10 +333,12 @@ void vfio_device_set_fd(VFIODevice *vbasedev, const char *str, Error **errp)
}
void vfio_device_init(VFIODevice *vbasedev, int type, VFIODeviceOps *ops,
- DeviceState *dev, bool ram_discard)
+ VFIODeviceIOOps *io_ops, DeviceState *dev,
+ bool ram_discard)
{
vbasedev->type = type;
vbasedev->ops = ops;
+ vbasedev->io_ops = io_ops;
vbasedev->dev = dev;
vbasedev->fd = -1;
@@ -463,3 +466,78 @@ void vfio_device_prepare(VFIODevice *vbasedev, VFIOContainerBase *bcontainer,
vfio_device_get_all_region_info(vbasedev);
}
+
+/*
+ * Traditional ioctl() based io
+ */
+
+static int vfio_device_io_device_feature(VFIODevice *vbasedev,
+ struct vfio_device_feature *feature)
+{
+ int ret;
+
+ ret = ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature);
+
+ return ret < 0 ? -errno : ret;
+}
+
+static int vfio_device_io_get_region_info(VFIODevice *vbasedev,
+ struct vfio_region_info *info)
+{
+ int ret;
+
+ ret = ioctl(vbasedev->fd, VFIO_DEVICE_GET_REGION_INFO, info);
+
+ return ret < 0 ? -errno : ret;
+}
+
+static int vfio_device_io_get_irq_info(VFIODevice *vbasedev,
+ struct vfio_irq_info *info)
+{
+ int ret;
+
+ ret = ioctl(vbasedev->fd, VFIO_DEVICE_GET_IRQ_INFO, info);
+
+ return ret < 0 ? -errno : ret;
+}
+
+static int vfio_device_io_set_irqs(VFIODevice *vbasedev,
+ struct vfio_irq_set *irqs)
+{
+ int ret;
+
+ ret = ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, irqs);
+
+ return ret < 0 ? -errno : ret;
+}
+
+static int vfio_device_io_region_read(VFIODevice *vbasedev, uint8_t index,
+ off_t off, uint32_t size, void *data)
+{
+ struct vfio_region_info *info = vbasedev->reginfo[index];
+ int ret;
+
+ ret = pread(vbasedev->fd, data, size, info->offset + off);
+
+ return ret < 0 ? -errno : ret;
+}
+
+static int vfio_device_io_region_write(VFIODevice *vbasedev, uint8_t index,
+ off_t off, uint32_t size, void *data)
+{
+ struct vfio_region_info *info = vbasedev->reginfo[index];
+ int ret;
+
+ ret = pwrite(vbasedev->fd, data, size, info->offset + off);
+
+ return ret < 0 ? -errno : ret;
+}
+
+VFIODeviceIOOps vfio_device_io_ops_ioctl = {
+ .device_feature = vfio_device_io_device_feature,
+ .get_region_info = vfio_device_io_get_region_info,
+ .get_irq_info = vfio_device_io_get_irq_info,
+ .set_irqs = vfio_device_io_set_irqs,
+ .region_read = vfio_device_io_region_read,
+ .region_write = vfio_device_io_region_write,
+};
diff --git a/hw/vfio/listener.c b/hw/vfio/listener.c
index bcf2b98e79..7ea9e0dfb7 100644
--- a/hw/vfio/listener.c
+++ b/hw/vfio/listener.c
@@ -821,13 +821,17 @@ static void vfio_devices_dma_logging_stop(VFIOContainerBase *bcontainer)
VFIO_DEVICE_FEATURE_DMA_LOGGING_STOP;
QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
+ int ret;
+
if (!vbasedev->dirty_tracking) {
continue;
}
- if (ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature)) {
+ ret = vbasedev->io_ops->device_feature(vbasedev, feature);
+
+ if (ret != 0) {
warn_report("%s: Failed to stop DMA logging, err %d (%s)",
- vbasedev->name, -errno, strerror(errno));
+ vbasedev->name, -ret, strerror(-ret));
}
vbasedev->dirty_tracking = false;
}
@@ -928,10 +932,9 @@ static bool vfio_devices_dma_logging_start(VFIOContainerBase *bcontainer,
continue;
}
- ret = ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature);
+ ret = vbasedev->io_ops->device_feature(vbasedev, feature);
if (ret) {
- ret = -errno;
- error_setg_errno(errp, errno, "%s: Failed to start DMA logging",
+ error_setg_errno(errp, -ret, "%s: Failed to start DMA logging",
vbasedev->name);
goto out;
}
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index b40d5abdfd..ff2b15ff02 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -381,7 +381,7 @@ static void vfio_msi_interrupt(void *opaque)
static int vfio_enable_msix_no_vec(VFIOPCIDevice *vdev)
{
g_autofree struct vfio_irq_set *irq_set = NULL;
- int ret = 0, argsz;
+ int argsz;
int32_t *fd;
argsz = sizeof(*irq_set) + sizeof(*fd);
@@ -396,9 +396,7 @@ static int vfio_enable_msix_no_vec(VFIOPCIDevice *vdev)
fd = (int32_t *)&irq_set->data;
*fd = -1;
- ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_SET_IRQS, irq_set);
-
- return ret < 0 ? -errno : ret;
+ return vdev->vbasedev.io_ops->set_irqs(&vdev->vbasedev, irq_set);
}
static int vfio_enable_vectors(VFIOPCIDevice *vdev, bool msix)
@@ -455,11 +453,11 @@ static int vfio_enable_vectors(VFIOPCIDevice *vdev, bool msix)
fds[i] = fd;
}
- ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_SET_IRQS, irq_set);
+ ret = vdev->vbasedev.io_ops->set_irqs(&vdev->vbasedev, irq_set);
g_free(irq_set);
- return ret < 0 ? -errno : ret;
+ return ret;
}
static void vfio_add_kvm_msi_virq(VFIOPCIDevice *vdev, VFIOMSIVector *vector,
@@ -917,18 +915,22 @@ static void vfio_pci_load_rom(VFIOPCIDevice *vdev)
memset(vdev->rom, 0xff, size);
while (size) {
- bytes = pread(vbasedev->fd, vdev->rom + off,
- size, vdev->rom_offset + off);
+ bytes = vbasedev->io_ops->region_read(vbasedev,
+ VFIO_PCI_ROM_REGION_INDEX,
+ off, size, vdev->rom + off);
+
if (bytes == 0) {
break;
} else if (bytes > 0) {
off += bytes;
size -= bytes;
} else {
- if (errno == EINTR || errno == EAGAIN) {
+ if (bytes == -EINTR || bytes == -EAGAIN) {
continue;
}
- error_report("vfio: Error reading device ROM: %m");
+ error_report("vfio: Error reading device ROM: %s",
+ strerror(-bytes));
+
break;
}
}
@@ -968,22 +970,18 @@ static void vfio_pci_load_rom(VFIOPCIDevice *vdev)
static int vfio_pci_config_space_read(VFIOPCIDevice *vdev, off_t offset,
uint32_t size, void *data)
{
- ssize_t ret;
-
- ret = pread(vdev->vbasedev.fd, data, size, vdev->config_offset + offset);
-
- return ret < 0 ? -errno : (int)ret;
+ return vdev->vbasedev.io_ops->region_read(&vdev->vbasedev,
+ VFIO_PCI_CONFIG_REGION_INDEX,
+ offset, size, data);
}
/* "Raw" write of underlying config space. */
static int vfio_pci_config_space_write(VFIOPCIDevice *vdev, off_t offset,
uint32_t size, void *data)
{
- ssize_t ret;
-
- ret = pwrite(vdev->vbasedev.fd, data, size, vdev->config_offset + offset);
-
- return ret < 0 ? -errno : (int)ret;
+ return vdev->vbasedev.io_ops->region_write(&vdev->vbasedev,
+ VFIO_PCI_CONFIG_REGION_INDEX,
+ offset, size, data);
}
static uint64_t vfio_rom_read(void *opaque, hwaddr addr, unsigned size)
@@ -3405,7 +3403,7 @@ static void vfio_instance_init(Object *obj)
vdev->host.function = ~0U;
vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_PCI, &vfio_pci_ops,
- DEVICE(vdev), false);
+ &vfio_device_io_ops_ioctl, DEVICE(vdev), false);
vdev->nv_gpudirect_clique = 0xFF;
diff --git a/hw/vfio/platform.c b/hw/vfio/platform.c
index fd176c18a4..28eedfa571 100644
--- a/hw/vfio/platform.c
+++ b/hw/vfio/platform.c
@@ -650,7 +650,7 @@ static void vfio_platform_instance_init(Object *obj)
VFIODevice *vbasedev = &vdev->vbasedev;
vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_PLATFORM, &vfio_platform_ops,
- DEVICE(vdev), false);
+ &vfio_device_io_ops_ioctl, DEVICE(vdev), false);
}
#ifdef CONFIG_IOMMUFD
diff --git a/hw/vfio/region.c b/hw/vfio/region.c
index ef2630cac3..35fb81c04a 100644
--- a/hw/vfio/region.c
+++ b/hw/vfio/region.c
@@ -45,6 +45,7 @@ void vfio_region_write(void *opaque, hwaddr addr,
uint32_t dword;
uint64_t qword;
} buf;
+ int ret;
switch (size) {
case 1:
@@ -64,11 +65,13 @@ void vfio_region_write(void *opaque, hwaddr addr,
break;
}
- if (pwrite(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) {
+ ret = vbasedev->io_ops->region_write(vbasedev, region->nr,
+ addr, size, &buf);
+ if (ret != size) {
error_report("%s(%s:region%d+0x%"HWADDR_PRIx", 0x%"PRIx64
- ",%d) failed: %m",
+ ",%d) failed: %s",
__func__, vbasedev->name, region->nr,
- addr, data, size);
+ addr, data, size, ret < 0 ? strerror(ret) : "short write");
}
trace_vfio_region_write(vbasedev->name, region->nr, addr, data, size);
@@ -96,11 +99,13 @@ uint64_t vfio_region_read(void *opaque,
uint64_t qword;
} buf;
uint64_t data = 0;
+ int ret;
- if (pread(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) {
- error_report("%s(%s:region%d+0x%"HWADDR_PRIx", %d) failed: %m",
+ ret = vbasedev->io_ops->region_read(vbasedev, region->nr, addr, size, &buf);
+ if (ret != size) {
+ error_report("%s(%s:region%d+0x%"HWADDR_PRIx", %d) failed: %s",
__func__, vbasedev->name, region->nr,
- addr, size);
+ addr, size, ret < 0 ? strerror(ret) : "short read");
return (uint64_t)-1;
}
switch (size) {
diff --git a/include/hw/vfio/vfio-device.h b/include/hw/vfio/vfio-device.h
index 967b07cd89..cb2f581826 100644
--- a/include/hw/vfio/vfio-device.h
+++ b/include/hw/vfio/vfio-device.h
@@ -41,6 +41,7 @@ enum {
};
typedef struct VFIODeviceOps VFIODeviceOps;
+typedef struct VFIODeviceIOOps VFIODeviceIOOps;
typedef struct VFIOMigration VFIOMigration;
typedef struct IOMMUFDBackend IOMMUFDBackend;
@@ -66,6 +67,7 @@ typedef struct VFIODevice {
OnOffAuto migration_multifd_transfer;
bool migration_events;
VFIODeviceOps *ops;
+ VFIODeviceIOOps *io_ops;
unsigned int num_irqs;
unsigned int num_regions;
unsigned int flags;
@@ -140,6 +142,25 @@ typedef QLIST_HEAD(VFIODeviceList, VFIODevice) VFIODeviceList;
extern VFIODeviceList vfio_device_list;
#ifdef CONFIG_LINUX
+/*
+ * How devices communicate with the server. The default option is through
+ * ioctl() to the kernel VFIO driver, but vfio-user can use a socket to a remote
+ * process.
+ */
+struct VFIODeviceIOOps {
+ int (*device_feature)(VFIODevice *vdev, struct vfio_device_feature *);
+ int (*get_region_info)(VFIODevice *vdev,
+ struct vfio_region_info *info);
+ int (*get_irq_info)(VFIODevice *vdev, struct vfio_irq_info *irq);
+ int (*set_irqs)(VFIODevice *vdev, struct vfio_irq_set *irqs);
+ int (*region_read)(VFIODevice *vdev, uint8_t nr, off_t off, uint32_t size,
+ void *data);
+ int (*region_write)(VFIODevice *vdev, uint8_t nr, off_t off, uint32_t size,
+ void *data);
+};
+
+extern VFIODeviceIOOps vfio_device_io_ops_ioctl;
+
int vfio_device_get_region_info(VFIODevice *vbasedev, int index,
struct vfio_region_info **info);
int vfio_device_get_region_info_type(VFIODevice *vbasedev, uint32_t type,
@@ -154,6 +175,7 @@ int vfio_device_get_irq_info(VFIODevice *vbasedev, int index,
bool vfio_device_get_name(VFIODevice *vbasedev, Error **errp);
void vfio_device_set_fd(VFIODevice *vbasedev, const char *str, Error **errp);
void vfio_device_init(VFIODevice *vbasedev, int type, VFIODeviceOps *ops,
- DeviceState *dev, bool ram_discard);
+ VFIODeviceIOOps *io_ops, DeviceState *dev,
+ bool ram_discard);
int vfio_device_get_aw_bits(VFIODevice *vdev);
#endif /* HW_VFIO_VFIO_COMMON_H */
--
2.34.1On 4/9/25 15:48, John Levon wrote:
> For vfio-user, device operations such as IRQ handling and region
> read/writes are implemented in userspace over the control socket, not
> ioctl() or read()/write() to the vfio kernel driver; add an ops vector
> to generalize this, and implement vfio_device_io_ops_ioctl for
> interacting with the kernel vfio driver.
>
> Originally-by: John Johnson <john.g.johnson@oracle.com>
> Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
> Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
> Signed-off-by: John Levon <john.levon@nutanix.com>
> ---
> hw/vfio/ap.c | 2 +-
> hw/vfio/ccw.c | 2 +-
> hw/vfio/container-base.c | 6 +-
> hw/vfio/device.c | 102 ++++++++++++++++++++++++++++++----
> hw/vfio/listener.c | 13 +++--
> hw/vfio/pci.c | 40 +++++++------
> hw/vfio/platform.c | 2 +-
> hw/vfio/region.c | 17 ++++--
> include/hw/vfio/vfio-device.h | 24 +++++++-
> 9 files changed, 155 insertions(+), 53 deletions(-)
>
> diff --git a/hw/vfio/ap.c b/hw/vfio/ap.c
> index f311bca5b6..b6233b2107 100644
> --- a/hw/vfio/ap.c
> +++ b/hw/vfio/ap.c
> @@ -229,7 +229,7 @@ static void vfio_ap_instance_init(Object *obj)
> * handle ram_block_discard_disable().
> */
> vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_AP, &vfio_ap_ops,
> - DEVICE(vapdev), true);
> + &vfio_device_io_ops_ioctl, DEVICE(vapdev), true);
We only have one io_ops implementation currently. Please drop all
the vfio_device_init() changes and keep vfio_device_io_ops_ioctl
static.
>
> /* AP device is mdev type device */
> vbasedev->mdev = true;
> diff --git a/hw/vfio/ccw.c b/hw/vfio/ccw.c
> index 14dee7cd19..aee52b5a8d 100644
> --- a/hw/vfio/ccw.c
> +++ b/hw/vfio/ccw.c
> @@ -676,7 +676,7 @@ static void vfio_ccw_instance_init(Object *obj)
> * ram_block_discard_disable().
> */
> vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_CCW, &vfio_ccw_ops,
> - DEVICE(vcdev), true);
> + &vfio_device_io_ops_ioctl, DEVICE(vcdev), true);
> }
>
> #ifdef CONFIG_IOMMUFD
> diff --git a/hw/vfio/container-base.c b/hw/vfio/container-base.c
> index 613fe1a00d..16fe5f79d2 100644
> --- a/hw/vfio/container-base.c
> +++ b/hw/vfio/container-base.c
> @@ -198,11 +198,7 @@ static int vfio_device_dma_logging_report(VFIODevice *vbasedev, hwaddr iova,
> feature->flags = VFIO_DEVICE_FEATURE_GET |
> VFIO_DEVICE_FEATURE_DMA_LOGGING_REPORT;
>
> - if (ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature)) {
> - return -errno;
> - }
> -
> - return 0;
> + return vbasedev->io_ops->device_feature(vbasedev, feature);
> }
>
> static int vfio_container_iommu_query_dirty_bitmap(const VFIOContainerBase *bcontainer,
> diff --git a/hw/vfio/device.c b/hw/vfio/device.c
> index 102fa5a9b4..545d9f1faf 100644
> --- a/hw/vfio/device.c
> +++ b/hw/vfio/device.c
> @@ -82,7 +82,7 @@ void vfio_device_irq_disable(VFIODevice *vbasedev, int index)
> .count = 0,
> };
>
> - ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
> + vbasedev->io_ops->set_irqs(vbasedev, &irq_set);
> }
>
> void vfio_device_irq_unmask(VFIODevice *vbasedev, int index)
> @@ -95,7 +95,7 @@ void vfio_device_irq_unmask(VFIODevice *vbasedev, int index)
> .count = 1,
> };
>
> - ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
> + vbasedev->io_ops->set_irqs(vbasedev, &irq_set);
> }
>
> void vfio_device_irq_mask(VFIODevice *vbasedev, int index)
> @@ -108,7 +108,7 @@ void vfio_device_irq_mask(VFIODevice *vbasedev, int index)
> .count = 1,
> };
>
> - ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
> + vbasedev->io_ops->set_irqs(vbasedev, &irq_set);
> }
>
> static inline const char *action_to_str(int action)
> @@ -155,6 +155,7 @@ bool vfio_device_irq_set_signaling(VFIODevice *vbasedev, int index, int subindex
> int argsz;
> const char *name;
> int32_t *pfd;
> + int ret;
>
> argsz = sizeof(*irq_set) + sizeof(*pfd);
>
> @@ -167,7 +168,9 @@ bool vfio_device_irq_set_signaling(VFIODevice *vbasedev, int index, int subindex
> pfd = (int32_t *)&irq_set->data;
> *pfd = fd;
>
> - if (!ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, irq_set)) {
> + ret = vbasedev->io_ops->set_irqs(vbasedev, irq_set);
> +
> + if (!ret) {
> return true;
> }
>
> @@ -188,22 +191,19 @@ bool vfio_device_irq_set_signaling(VFIODevice *vbasedev, int index, int subindex
> int vfio_device_get_irq_info(VFIODevice *vbasedev, int index,
> struct vfio_irq_info *info)
> {
> - int ret;
> -
> memset(info, 0, sizeof(*info));
>
> info->argsz = sizeof(*info);
> info->index = index;
>
> - ret = ioctl(vbasedev->fd, VFIO_DEVICE_GET_IRQ_INFO, info);
> -
> - return ret < 0 ? -errno : ret;
> + return vbasedev->io_ops->get_irq_info(vbasedev, info);
> }
>
> int vfio_device_get_region_info(VFIODevice *vbasedev, int index,
> struct vfio_region_info **info)
> {
> size_t argsz = sizeof(struct vfio_region_info);
> + int ret;
>
> /* create region info cache */
> if (vbasedev->reginfo == NULL) {
> @@ -222,10 +222,11 @@ int vfio_device_get_region_info(VFIODevice *vbasedev, int index,
> retry:
> (*info)->argsz = argsz;
>
> - if (ioctl(vbasedev->fd, VFIO_DEVICE_GET_REGION_INFO, *info)) {
> + ret = vbasedev->io_ops->get_region_info(vbasedev, *info);
> + if (ret != 0) {
> g_free(*info);
> *info = NULL;
> - return -errno;
> + return ret;
> }
>
> if ((*info)->argsz > argsz) {
> @@ -332,10 +333,12 @@ void vfio_device_set_fd(VFIODevice *vbasedev, const char *str, Error **errp)
> }
>
> void vfio_device_init(VFIODevice *vbasedev, int type, VFIODeviceOps *ops,
> - DeviceState *dev, bool ram_discard)
> + VFIODeviceIOOps *io_ops, DeviceState *dev,
> + bool ram_discard)
> {
> vbasedev->type = type;
> vbasedev->ops = ops;
> + vbasedev->io_ops = io_ops;
> vbasedev->dev = dev;
> vbasedev->fd = -1;
>
> @@ -463,3 +466,78 @@ void vfio_device_prepare(VFIODevice *vbasedev, VFIOContainerBase *bcontainer,
>
> vfio_device_get_all_region_info(vbasedev);
> }
> +
> +/*
> + * Traditional ioctl() based io
> + */
> +
> +static int vfio_device_io_device_feature(VFIODevice *vbasedev,
> + struct vfio_device_feature *feature)
> +{
> + int ret;
> +
> + ret = ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature);
> +
> + return ret < 0 ? -errno : ret;
> +}
> +
> +static int vfio_device_io_get_region_info(VFIODevice *vbasedev,
> + struct vfio_region_info *info)
> +{
> + int ret;
> +
> + ret = ioctl(vbasedev->fd, VFIO_DEVICE_GET_REGION_INFO, info);
> +
> + return ret < 0 ? -errno : ret;
> +}
> +
> +static int vfio_device_io_get_irq_info(VFIODevice *vbasedev,
> + struct vfio_irq_info *info)
> +{
> + int ret;
> +
> + ret = ioctl(vbasedev->fd, VFIO_DEVICE_GET_IRQ_INFO, info);
> +
> + return ret < 0 ? -errno : ret;
> +}
> +
> +static int vfio_device_io_set_irqs(VFIODevice *vbasedev,
> + struct vfio_irq_set *irqs)
> +{
> + int ret;
> +
> + ret = ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, irqs);
> +
> + return ret < 0 ? -errno : ret;
> +}
> +
> +static int vfio_device_io_region_read(VFIODevice *vbasedev, uint8_t index,
> + off_t off, uint32_t size, void *data)
> +{
> + struct vfio_region_info *info = vbasedev->reginfo[index];
> + int ret;
> +
> + ret = pread(vbasedev->fd, data, size, info->offset + off);
> +
> + return ret < 0 ? -errno : ret;
> +}
> +
> +static int vfio_device_io_region_write(VFIODevice *vbasedev, uint8_t index,
> + off_t off, uint32_t size, void *data)
> +{
> + struct vfio_region_info *info = vbasedev->reginfo[index];
> + int ret;
> +
> + ret = pwrite(vbasedev->fd, data, size, info->offset + off);
> +
> + return ret < 0 ? -errno : ret;
> +}
> +
> +VFIODeviceIOOps vfio_device_io_ops_ioctl = {
> + .device_feature = vfio_device_io_device_feature,
> + .get_region_info = vfio_device_io_get_region_info,
> + .get_irq_info = vfio_device_io_get_irq_info,
> + .set_irqs = vfio_device_io_set_irqs,
> + .region_read = vfio_device_io_region_read,
> + .region_write = vfio_device_io_region_write,
> +};
> diff --git a/hw/vfio/listener.c b/hw/vfio/listener.c
> index bcf2b98e79..7ea9e0dfb7 100644
> --- a/hw/vfio/listener.c
> +++ b/hw/vfio/listener.c
> @@ -821,13 +821,17 @@ static void vfio_devices_dma_logging_stop(VFIOContainerBase *bcontainer)
> VFIO_DEVICE_FEATURE_DMA_LOGGING_STOP;
>
> QLIST_FOREACH(vbasedev, &bcontainer->device_list, container_next) {
> + int ret;
> +
> if (!vbasedev->dirty_tracking) {
> continue;
> }
>
> - if (ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature)) {
> + ret = vbasedev->io_ops->device_feature(vbasedev, feature);
> +
> + if (ret != 0) {
> warn_report("%s: Failed to stop DMA logging, err %d (%s)",
> - vbasedev->name, -errno, strerror(errno));
> + vbasedev->name, -ret, strerror(-ret));
> }
> vbasedev->dirty_tracking = false;
> }
> @@ -928,10 +932,9 @@ static bool vfio_devices_dma_logging_start(VFIOContainerBase *bcontainer,
> continue;
> }
>
> - ret = ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature);
> + ret = vbasedev->io_ops->device_feature(vbasedev, feature);
> if (ret) {
> - ret = -errno;
> - error_setg_errno(errp, errno, "%s: Failed to start DMA logging",
> + error_setg_errno(errp, -ret, "%s: Failed to start DMA logging",
> vbasedev->name);
> goto out;
> }
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index b40d5abdfd..ff2b15ff02 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -381,7 +381,7 @@ static void vfio_msi_interrupt(void *opaque)
> static int vfio_enable_msix_no_vec(VFIOPCIDevice *vdev)
> {
> g_autofree struct vfio_irq_set *irq_set = NULL;
> - int ret = 0, argsz;
> + int argsz;
> int32_t *fd;
>
> argsz = sizeof(*irq_set) + sizeof(*fd);
> @@ -396,9 +396,7 @@ static int vfio_enable_msix_no_vec(VFIOPCIDevice *vdev)
> fd = (int32_t *)&irq_set->data;
> *fd = -1;
>
> - ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_SET_IRQS, irq_set);
> -
> - return ret < 0 ? -errno : ret;
> + return vdev->vbasedev.io_ops->set_irqs(&vdev->vbasedev, irq_set);
> }
>
> static int vfio_enable_vectors(VFIOPCIDevice *vdev, bool msix)
> @@ -455,11 +453,11 @@ static int vfio_enable_vectors(VFIOPCIDevice *vdev, bool msix)
> fds[i] = fd;
> }
>
> - ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_SET_IRQS, irq_set);
> + ret = vdev->vbasedev.io_ops->set_irqs(&vdev->vbasedev, irq_set);
>
> g_free(irq_set);
>
> - return ret < 0 ? -errno : ret;
> + return ret;
> }
>
> static void vfio_add_kvm_msi_virq(VFIOPCIDevice *vdev, VFIOMSIVector *vector,
> @@ -917,18 +915,22 @@ static void vfio_pci_load_rom(VFIOPCIDevice *vdev)
> memset(vdev->rom, 0xff, size);
>
> while (size) {
> - bytes = pread(vbasedev->fd, vdev->rom + off,
> - size, vdev->rom_offset + off);
> + bytes = vbasedev->io_ops->region_read(vbasedev,
> + VFIO_PCI_ROM_REGION_INDEX,
> + off, size, vdev->rom + off);
> +
> if (bytes == 0) {
> break;
> } else if (bytes > 0) {
> off += bytes;
> size -= bytes;
> } else {
> - if (errno == EINTR || errno == EAGAIN) {
> + if (bytes == -EINTR || bytes == -EAGAIN) {
> continue;
> }
> - error_report("vfio: Error reading device ROM: %m");
> + error_report("vfio: Error reading device ROM: %s",
> + strerror(-bytes));
> +
> break;
> }
> }
> @@ -968,22 +970,18 @@ static void vfio_pci_load_rom(VFIOPCIDevice *vdev)
> static int vfio_pci_config_space_read(VFIOPCIDevice *vdev, off_t offset,
> uint32_t size, void *data)
> {
> - ssize_t ret;
> -
> - ret = pread(vdev->vbasedev.fd, data, size, vdev->config_offset + offset);
> -
> - return ret < 0 ? -errno : (int)ret;
> + return vdev->vbasedev.io_ops->region_read(&vdev->vbasedev,
> + VFIO_PCI_CONFIG_REGION_INDEX,
> + offset, size, data);
> }
>
> /* "Raw" write of underlying config space. */
> static int vfio_pci_config_space_write(VFIOPCIDevice *vdev, off_t offset,
> uint32_t size, void *data)
> {
> - ssize_t ret;
> -
> - ret = pwrite(vdev->vbasedev.fd, data, size, vdev->config_offset + offset);
> -
> - return ret < 0 ? -errno : (int)ret;
> + return vdev->vbasedev.io_ops->region_write(&vdev->vbasedev,
> + VFIO_PCI_CONFIG_REGION_INDEX,
> + offset, size, data);
> }
>
> static uint64_t vfio_rom_read(void *opaque, hwaddr addr, unsigned size)
> @@ -3405,7 +3403,7 @@ static void vfio_instance_init(Object *obj)
> vdev->host.function = ~0U;
>
> vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_PCI, &vfio_pci_ops,
> - DEVICE(vdev), false);
> + &vfio_device_io_ops_ioctl, DEVICE(vdev), false);
>
> vdev->nv_gpudirect_clique = 0xFF;
>
> diff --git a/hw/vfio/platform.c b/hw/vfio/platform.c
> index fd176c18a4..28eedfa571 100644
> --- a/hw/vfio/platform.c
> +++ b/hw/vfio/platform.c
> @@ -650,7 +650,7 @@ static void vfio_platform_instance_init(Object *obj)
> VFIODevice *vbasedev = &vdev->vbasedev;
>
> vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_PLATFORM, &vfio_platform_ops,
> - DEVICE(vdev), false);
> + &vfio_device_io_ops_ioctl, DEVICE(vdev), false);
> }
>
> #ifdef CONFIG_IOMMUFD
> diff --git a/hw/vfio/region.c b/hw/vfio/region.c
> index ef2630cac3..35fb81c04a 100644
> --- a/hw/vfio/region.c
> +++ b/hw/vfio/region.c
> @@ -45,6 +45,7 @@ void vfio_region_write(void *opaque, hwaddr addr,
> uint32_t dword;
> uint64_t qword;
> } buf;
> + int ret;
>
> switch (size) {
> case 1:
> @@ -64,11 +65,13 @@ void vfio_region_write(void *opaque, hwaddr addr,
> break;
> }
>
> - if (pwrite(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) {
> + ret = vbasedev->io_ops->region_write(vbasedev, region->nr,
> + addr, size, &buf);
> + if (ret != size) {
> error_report("%s(%s:region%d+0x%"HWADDR_PRIx", 0x%"PRIx64
> - ",%d) failed: %m",
> + ",%d) failed: %s",
> __func__, vbasedev->name, region->nr,
> - addr, data, size);
> + addr, data, size, ret < 0 ? strerror(ret) : "short write");
> }
>
> trace_vfio_region_write(vbasedev->name, region->nr, addr, data, size);
> @@ -96,11 +99,13 @@ uint64_t vfio_region_read(void *opaque,
> uint64_t qword;
> } buf;
> uint64_t data = 0;
> + int ret;
>
> - if (pread(vbasedev->fd, &buf, size, region->fd_offset + addr) != size) {
> - error_report("%s(%s:region%d+0x%"HWADDR_PRIx", %d) failed: %m",
> + ret = vbasedev->io_ops->region_read(vbasedev, region->nr, addr, size, &buf);
> + if (ret != size) {
> + error_report("%s(%s:region%d+0x%"HWADDR_PRIx", %d) failed: %s",
> __func__, vbasedev->name, region->nr,
> - addr, size);
> + addr, size, ret < 0 ? strerror(ret) : "short read");
> return (uint64_t)-1;
> }
> switch (size) {
> diff --git a/include/hw/vfio/vfio-device.h b/include/hw/vfio/vfio-device.h
> index 967b07cd89..cb2f581826 100644
> --- a/include/hw/vfio/vfio-device.h
> +++ b/include/hw/vfio/vfio-device.h
> @@ -41,6 +41,7 @@ enum {
> };
>
> typedef struct VFIODeviceOps VFIODeviceOps;
> +typedef struct VFIODeviceIOOps VFIODeviceIOOps;
> typedef struct VFIOMigration VFIOMigration;
>
> typedef struct IOMMUFDBackend IOMMUFDBackend;
> @@ -66,6 +67,7 @@ typedef struct VFIODevice {
> OnOffAuto migration_multifd_transfer;
> bool migration_events;
> VFIODeviceOps *ops;
> + VFIODeviceIOOps *io_ops;
> unsigned int num_irqs;
> unsigned int num_regions;
> unsigned int flags;
> @@ -140,6 +142,25 @@ typedef QLIST_HEAD(VFIODeviceList, VFIODevice) VFIODeviceList;
> extern VFIODeviceList vfio_device_list;
>
> #ifdef CONFIG_LINUX
> +/*
> + * How devices communicate with the server. The default option is through
> + * ioctl() to the kernel VFIO driver, but vfio-user can use a socket to a remote
> + * process.
> + */
> +struct VFIODeviceIOOps {
> + int (*device_feature)(VFIODevice *vdev, struct vfio_device_feature *);
> + int (*get_region_info)(VFIODevice *vdev,
> + struct vfio_region_info *info);
> + int (*get_irq_info)(VFIODevice *vdev, struct vfio_irq_info *irq);
> + int (*set_irqs)(VFIODevice *vdev, struct vfio_irq_set *irqs);
> + int (*region_read)(VFIODevice *vdev, uint8_t nr, off_t off, uint32_t size,
> + void *data);
> + int (*region_write)(VFIODevice *vdev, uint8_t nr, off_t off, uint32_t size,
> + void *data);
> +};
Could you please add documentation for this new struct.
Thanks,
C.
> +extern VFIODeviceIOOps vfio_device_io_ops_ioctl;
> +
> int vfio_device_get_region_info(VFIODevice *vbasedev, int index,
> struct vfio_region_info **info);
> int vfio_device_get_region_info_type(VFIODevice *vbasedev, uint32_t type,
> @@ -154,6 +175,7 @@ int vfio_device_get_irq_info(VFIODevice *vbasedev, int index,
> bool vfio_device_get_name(VFIODevice *vbasedev, Error **errp);
> void vfio_device_set_fd(VFIODevice *vbasedev, const char *str, Error **errp);
> void vfio_device_init(VFIODevice *vbasedev, int type, VFIODeviceOps *ops,
> - DeviceState *dev, bool ram_discard);
> + VFIODeviceIOOps *io_ops, DeviceState *dev,
> + bool ram_discard);
> int vfio_device_get_aw_bits(VFIODevice *vdev);
> #endif /* HW_VFIO_VFIO_COMMON_H */
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