Currently it is not possible for userspace to map a DMABUF exported buffer
with write permissions. This patch allows to also pass O_RDONLY/O_RDWR when
exporting the buffer, so that userspace may map it with write permissions.
Signed-off-by: NPhilipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Earlier version of dma-contig allocator in user ptr mode assumed that in
all cases DMA address equals physical address. This was just a special case.
Commit e15dab75 introduced correct support
for converting userpage to dma address, but unfortunately it broke the
support for simple dma address = physical address for the case, when given
physical frame has no struct page associated with it (this happens if one
use for example dma_declare_coherent api or other reserved memory approach).
This commit restores support for such cases.
Signed-off-by: NMarek Szyprowski <m.szyprowski@samsung.com>
[s.nawrocki@samsung.com: replaced #elsif with #elif]
Signed-off-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>

Memory maps typically require that the buffer size to be page
aligned. Currently, two memops drivers do such alignment
internally, but videobuf-vmalloc doesn't.
Also, the buffer overflow check doesn't take it into account.
So, instead of doing it at each memops driver, enforce it at
VB2 core.
Reported-by: NPrabhakar lad <prabhakar.csengg@gmail.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Some drivers have special memory requirements for their buffers, usually
related to DMA (e.g. GFP_DMA or __GFP_DMA32). Make it possible to specify
additional GFP flags for those buffers by adding a gfp_flags field to
vb2_queue.
Note that this field will be replaced in the future with a different
mechanism, but that is still work in progress and we need this feature
now so we won't be able to convert drivers with such requirements to vb2.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Acked-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Acked-by: NFederico Vaga <federico.vaga@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The right solution is to remove the architecture dependency on
dma_common_get_sgtable(). Revert this patch to apply the right one.

This reverts commit 93049b93.

As reported by Stephen:

> After merging the v4l-dvb tree, today's linux-next build (x86_64
> allmodconfig) failed like this:
>
> ERROR: "dma_common_get_sgtable" [drivers/media/v4l2-core/videobuf2-dma-contig.ko] undefined!
>
> Caused by commit 9ef2cbeb ("[media] v4l: vb2-dma-contig: add support
> for DMABUF exporting").  dma_common_get_sgtable() is called from the
> inline dma_get_sgtable_attrs() and dma_get_sgtable_attrs() is "called
> from" dma_get_sgtable().  dma_common_get_sgtable() is only defined if
> ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY is set which depends on
> CONFIG_HAVE_GENERIC_DMA_COHERENT being set which it isn't for this build.

The simplest fix is to just not support DMABUF with vb2-contig, on archs
where this symbol doesn't exist. Some latter patch can rewrite it to
support this outside -arm.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Most operations on DMA and DMABUF framework require the size of a buffer to be
page aligned. This patch guarantees the requirement is satisfied for all
vb2-dma-contig buffers.
Signed-off-by: NTomasz Stanislawski <t.stanislaws@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The DMA transfer must be aligned to a specific value. If userptr is not aligned
to DMA requirements then unexpected corruptions of the memory may occur before
or after a buffer.  To prevent such situations, all unligned userptr buffers
are rejected at VIDIOC_QBUF.
Signed-off-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This patch adds taking reference to the device for MMAP buffers.
Such buffers, may be exported using DMABUF mechanism. If the driver that
created a queue is unloaded then the queue is released, the device might be
released too.  However, buffers cannot be released if they are referenced by
DMABUF descriptor(s). The device pointer kept in a buffer must be valid for the
whole buffer's lifetime. Therefore MMAP buffers should take a reference to the
device to avoid risk of dangling pointers.
Signed-off-by: NTomasz Stanislawski <t.stanislaws@samsung.com>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This patch adds support for exporting a dma-contig buffer using
DMABUF interface.
Signed-off-by: NTomasz Stanislawski <t.stanislaws@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Tested-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Let mmap method to use dma_mmap_coherent call.  Moreover, this patch removes
vb2_mmap_pfn_range from videobuf2 helpers as it was suggested by Laurent
Pinchart.  The function is no longer used in vb2 code.
Signed-off-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NTomasz Stanislawski <t.stanislaws@samsung.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This patch makes changes for adding dma-contig as a dma_buf user. It provides
function implementations for the {attach, detach, map, unmap}_dmabuf()
mem_ops of DMABUF memory type.
	[author of the original patch]
	[integration with refactored dma-contig allocator]
Signed-off-by: NSumit Semwal <sumit.semwal@ti.com>
Signed-off-by: NSumit Semwal <sumit.semwal@linaro.org>
Signed-off-by: NTomasz Stanislawski <t.stanislaws@samsung.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Add prepare/finish callbacks to vb2-dma-contig allocator.
Signed-off-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Tested-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This patch introduces usage of dma_map_sg to map memory behind
a userspace pointer to a device as dma-contiguous mapping.
This patch contains some of the code kindly provided by Marek Szyprowski
<m.szyprowski@samsung.com> and Kamil Debski <k.debski@samsung.com> and Andrzej
Pietrasiewicz <andrzej.p@samsung.com>. Kind thanks for bug reports from Laurent
Pinchart <laurent.pinchart@ideasonboard.com> and Seung-Woo Kim
<sw0312.kim@samsung.com>.
Signed-off-by: NTomasz Stanislawski <t.stanislaws@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Group functions by buffer type.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This patch removes a reference to alloc_ctx from an instance of a DMA
contiguous buffer. It helps to avoid a risk of a dangling pointer if the
context is released while the buffer is still valid. Moreover it removes one
dereference step while accessing a device structure.
Signed-off-by: NTomasz Stanislawski <t.stanislaws@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Tested-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NHans Verkuil <hans.verkuil@cisco.com>
Tested-by: NMauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Currently, the v4l2 core is mixed together with other non-core drivers.
Move them into a separate directory.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The function vb2_dma_contig_vaddr returns a void * not an integer.

Quiets the sparse noise:

warning: Using plain integer as NULL pointer
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Pawel Osciak <pawel@osciak.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Acked-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Include the header to pickup the definitions of the exported symbols.

Quiets the following sparse warnings:

warning: symbol 'vb2_dma_contig_memops' was not declared. Should it be static?
warning: symbol 'vb2_dma_contig_init_ctx' was not declared. Should it be static?
warning: symbol 'vb2_dma_contig_cleanup_ctx' was not declared. Should it be static?
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Pawel Osciak <pawel@osciak.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Include the header to pickup the definitions of the exported symbols.

Quiets the following sparse warnings:

warning: symbol 'vb2_dma_contig_memops' was not declared. Should it be static?
warning: symbol 'vb2_dma_contig_init_ctx' was not declared. Should it be static?
warning: symbol 'vb2_dma_contig_cleanup_ctx' was not declared. Should it be static?
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Pawel Osciak <pawel@osciak.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Acked-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The function vb2_dma_contig_vaddr returns a void * not an integer.

Quiets the sparse noise:

warning: Using plain integer as NULL pointer
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Pawel Osciak <pawel@osciak.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Acked-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Use the correct 'dma_addr' name for the buffer address. 'paddr' suggested
that this is the physical address in system memory. For most ARM platforms
these two are the same, but this is not a generic rule. 'dma_addr' will
also point better to dma-mapping api.
Signed-off-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
CC: Pawel Osciak <pawel@osciak.com>
Acked-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

buf->size is not yet initialised in videobuf2-dma-contig at the time of
the error message, use "size."
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

dma_addr_t may not fit into void* on some architectures. To be safe, make
vb2_dma_contig_cookie() return a pointer to dma_addr_t and dereference it
in vb2_dma_contig_plane_paddr() back to dma_addr_t.
Signed-off-by: NPawel Osciak <pawel@osciak.com>
Reported-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Signed-off-by: NPawel Osciak <pawel@osciak.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Add an implementation of DMA coherent memory allocator and handling
routines for videobuf2, implemented on top of dma_alloc_coherent() call.
Signed-off-by: NPawel Osciak <p.osciak@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NMarek Szyprowski <m.szyprowski@samsung.com>
CC: Pawel Osciak <pawel@osciak.com>
Reviewed-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>