Make the error handling more robust in virtio_gpu_init_udmabuf()
by introducing 'Error **' parameter to capture errors and using an
enum from VFIO to categorize Guest and Host errors. This allows
for better error reporting and handling of errors from
virtio_gpu_create_udmabuf() and virtio_gpu_remap_dmabuf().
Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
Cc: Alex Bennée <alex.bennee@linaro.org>
Cc: Akihiko Odaki <odaki@rsg.ci.i.u-tokyo.ac.jp>
Cc: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Cc: Alex Williamson <alex@shazbot.org>
Cc: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
---
hw/display/virtio-gpu-dmabuf.c | 65 ++++++++++++++++++++++------------
1 file changed, 43 insertions(+), 22 deletions(-)
diff --git a/hw/display/virtio-gpu-dmabuf.c b/hw/display/virtio-gpu-dmabuf.c
index 8d67ef7c2a..0a6b54fde5 100644
--- a/hw/display/virtio-gpu-dmabuf.c
+++ b/hw/display/virtio-gpu-dmabuf.c
@@ -18,6 +18,7 @@
#include "ui/console.h"
#include "hw/virtio/virtio-gpu.h"
#include "hw/virtio/virtio-gpu-pixman.h"
+#include "hw/vfio/vfio-device.h"
#include "trace.h"
#include "system/ramblock.h"
#include "system/hostmem.h"
@@ -27,16 +28,18 @@
#include "standard-headers/linux/udmabuf.h"
#include "standard-headers/drm/drm_fourcc.h"
-static void virtio_gpu_create_udmabuf(struct virtio_gpu_simple_resource *res)
+static int virtio_gpu_create_udmabuf(struct virtio_gpu_simple_resource *res,
+ Error **errp)
{
g_autofree struct udmabuf_create_list *list = NULL;
RAMBlock *rb;
ram_addr_t offset;
- int udmabuf, i;
+ int udmabuf, i, fd;
udmabuf = udmabuf_fd();
if (udmabuf < 0) {
- return;
+ error_setg(errp, "udmabuf device not available or enabled");
+ return VFIO_DMABUF_CREATE_ERR_UNSPEC;
}
list = g_malloc0(sizeof(struct udmabuf_create_list) +
@@ -45,7 +48,8 @@ static void virtio_gpu_create_udmabuf(struct virtio_gpu_simple_resource *res)
for (i = 0; i < res->iov_cnt; i++) {
rb = qemu_ram_block_from_host(res->iov[i].iov_base, false, &offset);
if (!rb || rb->fd < 0) {
- return;
+ error_setg(errp, "IOV memory address incompatible with udmabuf ");
+ return VFIO_DMABUF_CREATE_ERR_INVALID_IOV;
}
list->list[i].memfd = rb->fd;
@@ -56,22 +60,29 @@ static void virtio_gpu_create_udmabuf(struct virtio_gpu_simple_resource *res)
list->count = res->iov_cnt;
list->flags = UDMABUF_FLAGS_CLOEXEC;
- res->dmabuf_fd = ioctl(udmabuf, UDMABUF_CREATE_LIST, list);
- if (res->dmabuf_fd < 0) {
- warn_report("%s: UDMABUF_CREATE_LIST: %s", __func__,
- strerror(errno));
+ fd = ioctl(udmabuf, UDMABUF_CREATE_LIST, list);
+ if (fd < 0) {
+ error_setg_errno(errp, errno, "UDMABUF_CREATE_LIST: ioctl failed");
+ if (errno == EINVAL || errno == EBADFD) {
+ return VFIO_DMABUF_CREATE_ERR_INVALID_IOV;
+ }
+ return VFIO_DMABUF_CREATE_ERR_UNSPEC;
}
+ return fd;
}
-static void virtio_gpu_remap_dmabuf(struct virtio_gpu_simple_resource *res)
+static bool virtio_gpu_remap_dmabuf(struct virtio_gpu_simple_resource *res,
+ void **addr, Error **errp)
{
- res->remapped = mmap(NULL, res->blob_size, PROT_READ,
- MAP_SHARED, res->dmabuf_fd, 0);
- if (res->remapped == MAP_FAILED) {
- warn_report("%s: dmabuf mmap failed: %s", __func__,
- strerror(errno));
- res->remapped = NULL;
+ void *map;
+
+ map = mmap(NULL, res->blob_size, PROT_READ, MAP_SHARED, res->dmabuf_fd, 0);
+ if (map == MAP_FAILED) {
+ error_setg_errno(errp, errno, "dmabuf mmap failed");
+ return false;
}
+ *addr = map;
+ return true;
}
static void virtio_gpu_destroy_dmabuf(struct virtio_gpu_simple_resource *res)
@@ -125,22 +136,32 @@ bool virtio_gpu_have_udmabuf(void)
void virtio_gpu_init_dmabuf(struct virtio_gpu_simple_resource *res)
{
+ Error *local_err = NULL;
void *pdata = NULL;
- res->dmabuf_fd = -1;
if (res->iov_cnt == 1 &&
res->iov[0].iov_len < 4096) {
+ res->dmabuf_fd = -1;
pdata = res->iov[0].iov_base;
} else {
- virtio_gpu_create_udmabuf(res);
+ res->dmabuf_fd = virtio_gpu_create_udmabuf(res, &local_err);
+ if (res->dmabuf_fd == VFIO_DMABUF_CREATE_ERR_INVALID_IOV) {
+ error_free_or_abort(&local_err);
+
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "Cannot create dmabuf: incompatible memory\n");
+ return;
+ } else if (res->dmabuf_fd < 0 ||
+ !virtio_gpu_remap_dmabuf(res, &pdata, &local_err)) {
+ virtio_gpu_destroy_dmabuf(res);
+ res->dmabuf_fd = -1;
+ }
+
if (res->dmabuf_fd < 0) {
+ error_report_err(local_err);
return;
}
- virtio_gpu_remap_dmabuf(res);
- if (!res->remapped) {
- return;
- }
- pdata = res->remapped;
+ res->remapped = pdata;
}
res->blob = pdata;
--
2.53.0
On 2026/03/07 12:05, Vivek Kasireddy wrote:
> Make the error handling more robust in virtio_gpu_init_udmabuf()
> by introducing 'Error **' parameter to capture errors and using an
> enum from VFIO to categorize Guest and Host errors. This allows
> for better error reporting and handling of errors from
> virtio_gpu_create_udmabuf() and virtio_gpu_remap_dmabuf().
>
> Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
> Cc: Alex Bennée <alex.bennee@linaro.org>
> Cc: Akihiko Odaki <odaki@rsg.ci.i.u-tokyo.ac.jp>
> Cc: Dmitry Osipenko <dmitry.osipenko@collabora.com>
> Cc: Alex Williamson <alex@shazbot.org>
> Cc: Cédric Le Goater <clg@redhat.com>
> Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
> ---
> hw/display/virtio-gpu-dmabuf.c | 65 ++++++++++++++++++++++------------
> 1 file changed, 43 insertions(+), 22 deletions(-)
>
> diff --git a/hw/display/virtio-gpu-dmabuf.c b/hw/display/virtio-gpu-dmabuf.c
> index 8d67ef7c2a..0a6b54fde5 100644
> --- a/hw/display/virtio-gpu-dmabuf.c
> +++ b/hw/display/virtio-gpu-dmabuf.c
> @@ -18,6 +18,7 @@
> #include "ui/console.h"
> #include "hw/virtio/virtio-gpu.h"
> #include "hw/virtio/virtio-gpu-pixman.h"
> +#include "hw/vfio/vfio-device.h"
> #include "trace.h"
> #include "system/ramblock.h"
> #include "system/hostmem.h"
> @@ -27,16 +28,18 @@
> #include "standard-headers/linux/udmabuf.h"
> #include "standard-headers/drm/drm_fourcc.h"
>
> -static void virtio_gpu_create_udmabuf(struct virtio_gpu_simple_resource *res)
> +static int virtio_gpu_create_udmabuf(struct virtio_gpu_simple_resource *res,
> + Error **errp)
> {
> g_autofree struct udmabuf_create_list *list = NULL;
> RAMBlock *rb;
> ram_addr_t offset;
> - int udmabuf, i;
> + int udmabuf, i, fd;
>
> udmabuf = udmabuf_fd();
> if (udmabuf < 0) {
> - return;
> + error_setg(errp, "udmabuf device not available or enabled");
> + return VFIO_DMABUF_CREATE_ERR_UNSPEC;
> }
>
> list = g_malloc0(sizeof(struct udmabuf_create_list) +
> @@ -45,7 +48,8 @@ static void virtio_gpu_create_udmabuf(struct virtio_gpu_simple_resource *res)
> for (i = 0; i < res->iov_cnt; i++) {
> rb = qemu_ram_block_from_host(res->iov[i].iov_base, false, &offset);
> if (!rb || rb->fd < 0) {
> - return;
> + error_setg(errp, "IOV memory address incompatible with udmabuf ");
> + return VFIO_DMABUF_CREATE_ERR_INVALID_IOV;
> }
>
> list->list[i].memfd = rb->fd;
> @@ -56,22 +60,29 @@ static void virtio_gpu_create_udmabuf(struct virtio_gpu_simple_resource *res)
> list->count = res->iov_cnt;
> list->flags = UDMABUF_FLAGS_CLOEXEC;
>
> - res->dmabuf_fd = ioctl(udmabuf, UDMABUF_CREATE_LIST, list);
> - if (res->dmabuf_fd < 0) {
> - warn_report("%s: UDMABUF_CREATE_LIST: %s", __func__,
> - strerror(errno));
> + fd = ioctl(udmabuf, UDMABUF_CREATE_LIST, list);
> + if (fd < 0) {
> + error_setg_errno(errp, errno, "UDMABUF_CREATE_LIST: ioctl failed");
> + if (errno == EINVAL || errno == EBADFD) {
> + return VFIO_DMABUF_CREATE_ERR_INVALID_IOV;
> + }
> + return VFIO_DMABUF_CREATE_ERR_UNSPEC;
> }
> + return fd;
> }
>
> -static void virtio_gpu_remap_dmabuf(struct virtio_gpu_simple_resource *res)
> +static bool virtio_gpu_remap_dmabuf(struct virtio_gpu_simple_resource *res,
> + void **addr, Error **errp)
> {
> - res->remapped = mmap(NULL, res->blob_size, PROT_READ,
> - MAP_SHARED, res->dmabuf_fd, 0);
> - if (res->remapped == MAP_FAILED) {
> - warn_report("%s: dmabuf mmap failed: %s", __func__,
> - strerror(errno));
> - res->remapped = NULL;
> + void *map;
> +
> + map = mmap(NULL, res->blob_size, PROT_READ, MAP_SHARED, res->dmabuf_fd, 0);
> + if (map == MAP_FAILED) {
> + error_setg_errno(errp, errno, "dmabuf mmap failed");
> + return false;
> }
> + *addr = map;
> + return true;
> }
Following the convention, this function should return the mapped pointer
if success and return NULL otherwise.
Regards,
Akihiko Odaki
>
> static void virtio_gpu_destroy_dmabuf(struct virtio_gpu_simple_resource *res)
> @@ -125,22 +136,32 @@ bool virtio_gpu_have_udmabuf(void)
>
> void virtio_gpu_init_dmabuf(struct virtio_gpu_simple_resource *res)
> {
> + Error *local_err = NULL;
> void *pdata = NULL;
>
> - res->dmabuf_fd = -1;
> if (res->iov_cnt == 1 &&
> res->iov[0].iov_len < 4096) {
> + res->dmabuf_fd = -1;
> pdata = res->iov[0].iov_base;
> } else {
> - virtio_gpu_create_udmabuf(res);
> + res->dmabuf_fd = virtio_gpu_create_udmabuf(res, &local_err);
> + if (res->dmabuf_fd == VFIO_DMABUF_CREATE_ERR_INVALID_IOV) {
> + error_free_or_abort(&local_err);
> +
> + qemu_log_mask(LOG_GUEST_ERROR,
> + "Cannot create dmabuf: incompatible memory\n");
> + return;
> + } else if (res->dmabuf_fd < 0 ||
> + !virtio_gpu_remap_dmabuf(res, &pdata, &local_err)) {
> + virtio_gpu_destroy_dmabuf(res);
> + res->dmabuf_fd = -1;
> + }
> +
> if (res->dmabuf_fd < 0) {
> + error_report_err(local_err);
> return;
> }
> - virtio_gpu_remap_dmabuf(res);
> - if (!res->remapped) {
> - return;
> - }
> - pdata = res->remapped;
> + res->remapped = pdata;
> }
>
> res->blob = pdata;
Hi Akihiko,
> Subject: Re: [PATCH v10 09/10] virtio-gpu-dmabuf: Improve error handling
> with 'Error **' and err enum
>
> On 2026/03/07 12:05, Vivek Kasireddy wrote:
> > Make the error handling more robust in virtio_gpu_init_udmabuf()
> > by introducing 'Error **' parameter to capture errors and using an
> > enum from VFIO to categorize Guest and Host errors. This allows
> > for better error reporting and handling of errors from
> > virtio_gpu_create_udmabuf() and virtio_gpu_remap_dmabuf().
> >
> > Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
> > Cc: Alex Bennée <alex.bennee@linaro.org>
> > Cc: Akihiko Odaki <odaki@rsg.ci.i.u-tokyo.ac.jp>
> > Cc: Dmitry Osipenko <dmitry.osipenko@collabora.com>
> > Cc: Alex Williamson <alex@shazbot.org>
> > Cc: Cédric Le Goater <clg@redhat.com>
> > Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
> > ---
> > hw/display/virtio-gpu-dmabuf.c | 65 ++++++++++++++++++++++----------
> --
> > 1 file changed, 43 insertions(+), 22 deletions(-)
> >
> > diff --git a/hw/display/virtio-gpu-dmabuf.c b/hw/display/virtio-gpu-
> dmabuf.c
> > index 8d67ef7c2a..0a6b54fde5 100644
> > --- a/hw/display/virtio-gpu-dmabuf.c
> > +++ b/hw/display/virtio-gpu-dmabuf.c
> > @@ -18,6 +18,7 @@
> > #include "ui/console.h"
> > #include "hw/virtio/virtio-gpu.h"
> > #include "hw/virtio/virtio-gpu-pixman.h"
> > +#include "hw/vfio/vfio-device.h"
> > #include "trace.h"
> > #include "system/ramblock.h"
> > #include "system/hostmem.h"
> > @@ -27,16 +28,18 @@
> > #include "standard-headers/linux/udmabuf.h"
> > #include "standard-headers/drm/drm_fourcc.h"
> >
> > -static void virtio_gpu_create_udmabuf(struct
> virtio_gpu_simple_resource *res)
> > +static int virtio_gpu_create_udmabuf(struct
> virtio_gpu_simple_resource *res,
> > + Error **errp)
> > {
> > g_autofree struct udmabuf_create_list *list = NULL;
> > RAMBlock *rb;
> > ram_addr_t offset;
> > - int udmabuf, i;
> > + int udmabuf, i, fd;
> >
> > udmabuf = udmabuf_fd();
> > if (udmabuf < 0) {
> > - return;
> > + error_setg(errp, "udmabuf device not available or enabled");
> > + return VFIO_DMABUF_CREATE_ERR_UNSPEC;
> > }
> >
> > list = g_malloc0(sizeof(struct udmabuf_create_list) +
> > @@ -45,7 +48,8 @@ static void virtio_gpu_create_udmabuf(struct
> virtio_gpu_simple_resource *res)
> > for (i = 0; i < res->iov_cnt; i++) {
> > rb = qemu_ram_block_from_host(res->iov[i].iov_base, false,
> &offset);
> > if (!rb || rb->fd < 0) {
> > - return;
> > + error_setg(errp, "IOV memory address incompatible with
> udmabuf ");
> > + return VFIO_DMABUF_CREATE_ERR_INVALID_IOV;
> > }
> >
> > list->list[i].memfd = rb->fd;
> > @@ -56,22 +60,29 @@ static void virtio_gpu_create_udmabuf(struct
> virtio_gpu_simple_resource *res)
> > list->count = res->iov_cnt;
> > list->flags = UDMABUF_FLAGS_CLOEXEC;
> >
> > - res->dmabuf_fd = ioctl(udmabuf, UDMABUF_CREATE_LIST, list);
> > - if (res->dmabuf_fd < 0) {
> > - warn_report("%s: UDMABUF_CREATE_LIST: %s", __func__,
> > - strerror(errno));
> > + fd = ioctl(udmabuf, UDMABUF_CREATE_LIST, list);
> > + if (fd < 0) {
> > + error_setg_errno(errp, errno, "UDMABUF_CREATE_LIST: ioctl
> failed");
> > + if (errno == EINVAL || errno == EBADFD) {
> > + return VFIO_DMABUF_CREATE_ERR_INVALID_IOV;
> > + }
> > + return VFIO_DMABUF_CREATE_ERR_UNSPEC;
> > }
> > + return fd;
> > }
> >
> > -static void virtio_gpu_remap_dmabuf(struct
> virtio_gpu_simple_resource *res)
> > +static bool virtio_gpu_remap_dmabuf(struct
> virtio_gpu_simple_resource *res,
> > + void **addr, Error **errp)
> > {
> > - res->remapped = mmap(NULL, res->blob_size, PROT_READ,
> > - MAP_SHARED, res->dmabuf_fd, 0);
> > - if (res->remapped == MAP_FAILED) {
> > - warn_report("%s: dmabuf mmap failed: %s", __func__,
> > - strerror(errno));
> > - res->remapped = NULL;
> > + void *map;
> > +
> > + map = mmap(NULL, res->blob_size, PROT_READ, MAP_SHARED, res-
> >dmabuf_fd, 0);
> > + if (map == MAP_FAILED) {
> > + error_setg_errno(errp, errno, "dmabuf mmap failed");
> > + return false;
> > }
> > + *addr = map;
> > + return true;
> > }
>
> Following the convention, this function should return the mapped pointer
> if success and return NULL otherwise.
Ok, I'll make the change. I am guessing I should also make a similar change to
vfio_device_mmap_dmabuf() right?
Thanks,
Vivek
>
> Regards,
> Akihiko Odaki
>
> >
> > static void virtio_gpu_destroy_dmabuf(struct
> virtio_gpu_simple_resource *res)
> > @@ -125,22 +136,32 @@ bool virtio_gpu_have_udmabuf(void)
> >
> > void virtio_gpu_init_dmabuf(struct virtio_gpu_simple_resource *res)
> > {
> > + Error *local_err = NULL;
> > void *pdata = NULL;
> >
> > - res->dmabuf_fd = -1;
> > if (res->iov_cnt == 1 &&
> > res->iov[0].iov_len < 4096) {
> > + res->dmabuf_fd = -1;
> > pdata = res->iov[0].iov_base;
> > } else {
> > - virtio_gpu_create_udmabuf(res);
> > + res->dmabuf_fd = virtio_gpu_create_udmabuf(res, &local_err);
> > + if (res->dmabuf_fd == VFIO_DMABUF_CREATE_ERR_INVALID_IOV)
> {
> > + error_free_or_abort(&local_err);
> > +
> > + qemu_log_mask(LOG_GUEST_ERROR,
> > + "Cannot create dmabuf: incompatible memory\n");
> > + return;
> > + } else if (res->dmabuf_fd < 0 ||
> > + !virtio_gpu_remap_dmabuf(res, &pdata, &local_err)) {
> > + virtio_gpu_destroy_dmabuf(res);
> > + res->dmabuf_fd = -1;
> > + }
> > +
> > if (res->dmabuf_fd < 0) {
> > + error_report_err(local_err);
> > return;
> > }
> > - virtio_gpu_remap_dmabuf(res);
> > - if (!res->remapped) {
> > - return;
> > - }
> > - pdata = res->remapped;
> > + res->remapped = pdata;
> > }
> >
> > res->blob = pdata;
On 2026/03/10 14:38, Kasireddy, Vivek wrote:
> Hi Akihiko,
>
>> Subject: Re: [PATCH v10 09/10] virtio-gpu-dmabuf: Improve error handling
>> with 'Error **' and err enum
>>
>> On 2026/03/07 12:05, Vivek Kasireddy wrote:
>>> Make the error handling more robust in virtio_gpu_init_udmabuf()
>>> by introducing 'Error **' parameter to capture errors and using an
>>> enum from VFIO to categorize Guest and Host errors. This allows
>>> for better error reporting and handling of errors from
>>> virtio_gpu_create_udmabuf() and virtio_gpu_remap_dmabuf().
>>>
>>> Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
>>> Cc: Alex Bennée <alex.bennee@linaro.org>
>>> Cc: Akihiko Odaki <odaki@rsg.ci.i.u-tokyo.ac.jp>
>>> Cc: Dmitry Osipenko <dmitry.osipenko@collabora.com>
>>> Cc: Alex Williamson <alex@shazbot.org>
>>> Cc: Cédric Le Goater <clg@redhat.com>
>>> Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
>>> ---
>>> hw/display/virtio-gpu-dmabuf.c | 65 ++++++++++++++++++++++----------
>> --
>>> 1 file changed, 43 insertions(+), 22 deletions(-)
>>>
>>> diff --git a/hw/display/virtio-gpu-dmabuf.c b/hw/display/virtio-gpu-
>> dmabuf.c
>>> index 8d67ef7c2a..0a6b54fde5 100644
>>> --- a/hw/display/virtio-gpu-dmabuf.c
>>> +++ b/hw/display/virtio-gpu-dmabuf.c
>>> @@ -18,6 +18,7 @@
>>> #include "ui/console.h"
>>> #include "hw/virtio/virtio-gpu.h"
>>> #include "hw/virtio/virtio-gpu-pixman.h"
>>> +#include "hw/vfio/vfio-device.h"
>>> #include "trace.h"
>>> #include "system/ramblock.h"
>>> #include "system/hostmem.h"
>>> @@ -27,16 +28,18 @@
>>> #include "standard-headers/linux/udmabuf.h"
>>> #include "standard-headers/drm/drm_fourcc.h"
>>>
>>> -static void virtio_gpu_create_udmabuf(struct
>> virtio_gpu_simple_resource *res)
>>> +static int virtio_gpu_create_udmabuf(struct
>> virtio_gpu_simple_resource *res,
>>> + Error **errp)
>>> {
>>> g_autofree struct udmabuf_create_list *list = NULL;
>>> RAMBlock *rb;
>>> ram_addr_t offset;
>>> - int udmabuf, i;
>>> + int udmabuf, i, fd;
>>>
>>> udmabuf = udmabuf_fd();
>>> if (udmabuf < 0) {
>>> - return;
>>> + error_setg(errp, "udmabuf device not available or enabled");
>>> + return VFIO_DMABUF_CREATE_ERR_UNSPEC;
>>> }
>>>
>>> list = g_malloc0(sizeof(struct udmabuf_create_list) +
>>> @@ -45,7 +48,8 @@ static void virtio_gpu_create_udmabuf(struct
>> virtio_gpu_simple_resource *res)
>>> for (i = 0; i < res->iov_cnt; i++) {
>>> rb = qemu_ram_block_from_host(res->iov[i].iov_base, false,
>> &offset);
>>> if (!rb || rb->fd < 0) {
>>> - return;
>>> + error_setg(errp, "IOV memory address incompatible with
>> udmabuf ");
>>> + return VFIO_DMABUF_CREATE_ERR_INVALID_IOV;
>>> }
>>>
>>> list->list[i].memfd = rb->fd;
>>> @@ -56,22 +60,29 @@ static void virtio_gpu_create_udmabuf(struct
>> virtio_gpu_simple_resource *res)
>>> list->count = res->iov_cnt;
>>> list->flags = UDMABUF_FLAGS_CLOEXEC;
>>>
>>> - res->dmabuf_fd = ioctl(udmabuf, UDMABUF_CREATE_LIST, list);
>>> - if (res->dmabuf_fd < 0) {
>>> - warn_report("%s: UDMABUF_CREATE_LIST: %s", __func__,
>>> - strerror(errno));
>>> + fd = ioctl(udmabuf, UDMABUF_CREATE_LIST, list);
>>> + if (fd < 0) {
>>> + error_setg_errno(errp, errno, "UDMABUF_CREATE_LIST: ioctl
>> failed");
>>> + if (errno == EINVAL || errno == EBADFD) {
>>> + return VFIO_DMABUF_CREATE_ERR_INVALID_IOV;
>>> + }
>>> + return VFIO_DMABUF_CREATE_ERR_UNSPEC;
>>> }
>>> + return fd;
>>> }
>>>
>>> -static void virtio_gpu_remap_dmabuf(struct
>> virtio_gpu_simple_resource *res)
>>> +static bool virtio_gpu_remap_dmabuf(struct
>> virtio_gpu_simple_resource *res,
>>> + void **addr, Error **errp)
>>> {
>>> - res->remapped = mmap(NULL, res->blob_size, PROT_READ,
>>> - MAP_SHARED, res->dmabuf_fd, 0);
>>> - if (res->remapped == MAP_FAILED) {
>>> - warn_report("%s: dmabuf mmap failed: %s", __func__,
>>> - strerror(errno));
>>> - res->remapped = NULL;
>>> + void *map;
>>> +
>>> + map = mmap(NULL, res->blob_size, PROT_READ, MAP_SHARED, res-
>>> dmabuf_fd, 0);
>>> + if (map == MAP_FAILED) {
>>> + error_setg_errno(errp, errno, "dmabuf mmap failed");
>>> + return false;
>>> }
>>> + *addr = map;
>>> + return true;
>>> }
>>
>> Following the convention, this function should return the mapped pointer
>> if success and return NULL otherwise.
> Ok, I'll make the change. I am guessing I should also make a similar change to
> vfio_device_mmap_dmabuf() right?
Yes, I think that's a good idea.
Regards,
Akihiko Odaki
>
> Thanks,
> Vivek
>
>>
>> Regards,
>> Akihiko Odaki
>>
>>>
>>> static void virtio_gpu_destroy_dmabuf(struct
>> virtio_gpu_simple_resource *res)
>>> @@ -125,22 +136,32 @@ bool virtio_gpu_have_udmabuf(void)
>>>
>>> void virtio_gpu_init_dmabuf(struct virtio_gpu_simple_resource *res)
>>> {
>>> + Error *local_err = NULL;
>>> void *pdata = NULL;
>>>
>>> - res->dmabuf_fd = -1;
>>> if (res->iov_cnt == 1 &&
>>> res->iov[0].iov_len < 4096) {
>>> + res->dmabuf_fd = -1;
>>> pdata = res->iov[0].iov_base;
>>> } else {
>>> - virtio_gpu_create_udmabuf(res);
>>> + res->dmabuf_fd = virtio_gpu_create_udmabuf(res, &local_err);
>>> + if (res->dmabuf_fd == VFIO_DMABUF_CREATE_ERR_INVALID_IOV)
>> {
>>> + error_free_or_abort(&local_err);
>>> +
>>> + qemu_log_mask(LOG_GUEST_ERROR,
>>> + "Cannot create dmabuf: incompatible memory\n");
>>> + return;
>>> + } else if (res->dmabuf_fd < 0 ||
>>> + !virtio_gpu_remap_dmabuf(res, &pdata, &local_err)) {
>>> + virtio_gpu_destroy_dmabuf(res);
>>> + res->dmabuf_fd = -1;
>>> + }
>>> +
>>> if (res->dmabuf_fd < 0) {
>>> + error_report_err(local_err);
>>> return;
>>> }
>>> - virtio_gpu_remap_dmabuf(res);
>>> - if (!res->remapped) {
>>> - return;
>>> - }
>>> - pdata = res->remapped;
>>> + res->remapped = pdata;
>>> }
>>>
>>> res->blob = pdata;
>
© 2016 - 2026 Red Hat, Inc.