Commit Graph

21 Commits

Author SHA1 Message Date
Jason Gunthorpe
3cb2482714 vfio/mbochs: Fix close when multiple device FDs are open
mbochs_close() iterates over global device state and frees it. Currently
this is done every time a device FD is closed, but if multiple device FDs
are open this could corrupt other still active FDs.

Change this to use close_device() so it only runs on the last close.

Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/11-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-11 09:50:11 -06:00
Jason Gunthorpe
17a1e4fa3f vfio/samples: Delete useless open/close
The core code no longer requires these ops to be defined, so delete these
empty functions and leave the op as NULL. mtty's functions only log a
pointless message, delete that entirely.

Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/5-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-11 09:50:11 -06:00
Max Gurtovoy
ae03c3771b vfio: Introduce a vfio_uninit_group_dev() API call
This pairs with vfio_init_group_dev() and allows undoing any state that is
stored in the vfio_device unrelated to registration. Add appropriately
placed calls to all the drivers.

The following patch will use this to add pre-registration state for the
device set.

Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/3-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-11 09:50:10 -06:00
Jason Gunthorpe
de5494af48 vfio/mbochs: Fix missing error unwind of mbochs_used_mbytes
Convert mbochs to use an atomic scheme for this like mtty was changed
into. The atomic fixes various race conditions with probing. Add the
missing error unwind. Also add the missing kfree of mdev_state->pages.

Fixes: 681c1615f8 ("vfio/mbochs: Convert to use vfio_register_group_dev()")
Reported-by: Cornelia Huck <cohuck@redhat.com>
Co-developed-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/2-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-11 09:50:10 -06:00
Jason Gunthorpe
e1706f0764 vfio/samples: Remove module get/put
The patch to move the get/put to core and the patch to convert the samples
to use vfio_device crossed in a way that this was missed. When both
patches are together the samples do not need their own get/put.

Fixes: 437e41368c ("vfio/mdpy: Convert to use vfio_register_group_dev()")
Fixes: 681c1615f8 ("vfio/mbochs: Convert to use vfio_register_group_dev()")
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Link: https://lore.kernel.org/r/1-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-11 09:50:10 -06:00
Jason Gunthorpe
681c1615f8 vfio/mbochs: Convert to use vfio_register_group_dev()
This is straightforward conversion, the mdev_state is actually serving as
the vfio_device and we can replace all the mdev_get_drvdata()'s and the
wonky dead code with a simple container_of().

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20210617142218.1877096-11-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-06-21 15:29:25 -06:00
Dan Carpenter
698f99ed5e vfio/mdev: remove unnecessary NULL check in mbochs_create()
Originally "type" could be NULL and these checks were required, but we
recently changed how "type" is assigned and that's no longer the case.
Now "type" points to an element in the middle of a non-NULL array.

Removing the checks does not affect runtime at all, but it makes the
code a little bit simpler to read.

Fixes: 3d3a360e57 ("vfio/mbochs: Use mdev_get_type_group_id()")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <20210429095327.GY1981@kadam>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-05-04 09:56:02 -06:00
Jason Gunthorpe
9169cff168 vfio/mdev: Correct the function signatures for the mdev_type_attributes
The driver core standard is to pass in the properly typed object, the
properly typed attribute and the buffer data. It stems from the root
kobject method:

  ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *attr,..)

Each subclass of kobject should provide their own function with the same
signature but more specific types, eg struct device uses:

  ssize_t (*show)(struct device *dev, struct device_attribute *attr,..)

In this case the existing signature is:

  ssize_t (*show)(struct kobject *kobj, struct device *dev,..)

Where kobj is a 'struct mdev_type *' and dev is 'mdev_type->parent->dev'.

Change the mdev_type related sysfs attribute functions to:

  ssize_t (*show)(struct mdev_type *mtype, struct mdev_type_attribute *attr,..)

In order to restore type safety and match the driver core standard

There are no current users of 'attr', but if it is ever needed it would be
hard to add in retroactively, so do it now.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <18-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-12 10:36:00 -06:00
Jason Gunthorpe
c2ef2f50ad vfio/mdev: Remove kobj from mdev_parent_ops->create()
The kobj here is a type-erased version of mdev_type, which is already
stored in the struct mdev_device being passed in. It was only ever used to
compute the type_group_id, which is now extracted directly from the mdev.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <17-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-12 10:36:00 -06:00
Jason Gunthorpe
3d3a360e57 vfio/mbochs: Use mdev_get_type_group_id()
The mbochs_types array is parallel to the supported_type_groups array, so
the type_group_id indexes both. Instead of doing string searching just
directly index with type_group_id in all places.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <14-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-07 15:39:19 -06:00
Jason Gunthorpe
6cbf507fd0 vfio/mdev: Fix missing static's on MDEV_TYPE_ATTR's
These should always be prefixed with static, otherwise compilation
will fail on non-modular builds with

ld: samples/vfio-mdev/mbochs.o:(.data+0x2e0): multiple definition of `mdev_type_attr_name'; samples/vfio-mdev/mdpy.o:(.data+0x240): first defined here

Fixes: a5e6e6505f ("sample: vfio bochs vbe display (host device for bochs-drm)")
Fixes: d61fc96f47 ("sample: vfio mdev display - host device")
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Message-Id: <1-v2-d36939638fc6+d54-vfio2_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-04-07 15:39:15 -06:00
Marek Szyprowski
be0704beb2 samples: vfio-mdev/mbochs: fix common struct sg_table related issues
The Documentation/DMA-API-HOWTO.txt states that the dma_map_sg() function
returns the number of the created entries in the DMA address space.
However the subsequent calls to the dma_sync_sg_for_{device,cpu}() and
dma_unmap_sg must be called with the original number of the entries
passed to the dma_map_sg().

struct sg_table is a common structure used for describing a non-contiguous
memory buffer, used commonly in the DRM and graphics subsystems. It
consists of a scatterlist with memory pages and DMA addresses (sgl entry),
as well as the number of scatterlist entries: CPU pages (orig_nents entry)
and DMA mapped pages (nents entry).

It turned out that it was a common mistake to misuse nents and orig_nents
entries, calling DMA-mapping functions with a wrong number of entries or
ignoring the number of mapped entries returned by the dma_map_sg()
function.

To avoid such issues, lets use a common dma-mapping wrappers operating
directly on the struct sg_table objects and use scatterlist page
iterators where possible. This, almost always, hides references to the
nents and orig_nents entries, making the code robust, easier to follow
and copy/paste safe.

While touching this code, also add missing call to dma_unmap_sgtable.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
2020-09-10 08:19:46 +02:00
Daniel Vetter
59c3797076 sample/vfio-mdev/mbocs: Remove dma_buf_k(un)map support
No in-tree users left.

Acked-by: Sumit Semwal <sumit.semwal@linaro.org>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Kirti Wankhede <kwankhede@nvidia.com>
Cc: kvm@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20191118103536.17675-15-daniel.vetter@ffwll.ch
2019-11-25 22:37:30 +01:00
YueHaibing
b46c820f8f sample/mdev/mbochs: remove set but not used variable 'mdev_state'
Fixes gcc '-Wunused-but-set-variable' warning:

samples/vfio-mdev/mbochs.c: In function mbochs_ioctl:
samples/vfio-mdev/mbochs.c:1188:21: warning: variable mdev_state set but not used [-Wunused-but-set-variable]

It's not used any more since commit 104c7405a6 ("vfio:
add edid support to mbochs sample driver")

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2019-07-02 11:44:15 -06:00
Chengguang Xu
16355214a5 samples/vfio-mdev/mbochs: expand minor range when registering chrdev region
Actually, total amount of available minor number
for a single major is MINORMARK + 1. So expand
minor range when registering chrdev region.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2019-02-12 13:21:05 -07:00
Gerd Hoffmann
104c7405a6 vfio: add edid support to mbochs sample driver
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-10-11 10:22:36 -06:00
Alexey Khoroshilov
498e8bf51c sample: vfio-mdev: avoid deadlock in mdev_access()
mdev_access() calls mbochs_get_page() with mdev_state->ops_lock held,
while mbochs_get_page() locks the mutex by itself.
It leads to unavoidable deadlock.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-07-11 13:22:41 -06:00
Souptick Joarder
d7ef4899d7 sample/vfio-mdev: Change return type to vm_fault_t
convert mbochs_region_vm_fault and mbochs_dmabuf_vm_fault
to return vm_fault_t type.

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-07-04 10:42:04 -06:00
Gerd Hoffmann
7733e05b34 sample/mdev/mbochs: add mbochs_kunmap_dmabuf
There is no default implementation for dma_buf_ops->unmap.
So add a function unmapping the page, otherwise we'll leak them.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-06-26 00:27:23 -06:00
Gerd Hoffmann
2203d8a76e sample/mdev/mbochs: remove mbochs_kmap_atomic_dmabuf
Atomic mapping interface for dmabufs will be removed.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-06-26 00:27:22 -06:00
Gerd Hoffmann
a5e6e6505f sample: vfio bochs vbe display (host device for bochs-drm)
Display device, demo-ing the vfio dmabuf display interface
(VFIO_GFX_PLANE_TYPE_DMABUF).  Compatible enough to qemu stdvga
that bochs-drm.ko can be used as guest driver.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2018-06-08 10:24:16 -06:00