Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

As pointed by Laurent:

I think min_t(size_t, PAGE_SIZE, size) is the preferred way.

Thanks-to: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/videobuf-dma-sg.c: In function ‘videobuf_pages_to_sg’:
drivers/media/video/videobuf-dma-sg.c:119: warning: comparison of distinct pointer types lacks a cast
drivers/media/video/videobuf-dma-sg.c:120: warning: comparison of distinct pointer types lacks a cast
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Add an ext_lock argument to the videobuf init functions. This allows
drivers to pass the vdev->lock pointer (or any other externally held lock)
to videobuf. For now all drivers just pass NULL.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Currently videobuf uses the vb_lock mutex to lock its data structures.
But this locking will (optionally) move into the v4l2 core, which means
that in that case vb_lock shouldn't be used since the external lock is already
held.

Prepare for this by adding a pointer to such an external mutex and
don't lock if that pointer is set.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This fixes a nasty memory corruption bug when using userptr I/O.
The function videobuf_pages_to_sg() sets up the scatter-gather list for the
DMA transfer to the userspace pages. The first transfer is setup correctly
(the size is set to PAGE_SIZE - offset), but all other transfers have size
PAGE_SIZE. This is wrong for the last transfer which may be less than PAGE_SIZE.

Most, if not all, drivers will program the boards DMA engine correctly, i.e.
even though the size in the last sg element is wrong, they will do their
own size calculations and make sure the right amount is DMA-ed, and so seemingly
prevent memory corruption.

However, behind the scenes the dynamic DMA mapping support (in lib/swiotlb.c)
may create bounce buffers if the memory pages are not in DMA-able memory.
This happens for example on a 64-bit linux with a board that only supports
32-bit DMA.

These bounce buffers DO use the information in the sg list to determine the
size. So while the DMA engine transfers the correct amount of data, when the
data is 'bounced' back too much is copied, causing buffer overwrites.

The fix is simple: calculate and set the correct size for the last sg list
element.
Signed-off-by: NHans Verkuil <hans.verkuil@tandberg.com>
Cc: stable@kernel.org
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The videobuf_dmabuf and videobuf_vmalloc_memory fields have a vmalloc
field to store the kernel virtual address of vmalloc'ed buffers. Rename
the field to vaddr.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The fields are assigned but never used, remove them.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Those functions are only called inside videobuf-dma-sg.c, make them
static.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Instead of creating dirty wrappers around videobuf_dma_map/unmap that
create a dummy videobuf_queue structure, modify videobuf_dma_map/unmap
to take a device pointer argument and use it directly. The
videobuf_sg_dma_map/unmap then become unused and can be removed.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

These functions allocate videobuf_buffer structures only. Renaming in order
to prevent confusion with functions allocating actual video buffer memory.

Rename the functions in videobuf-core.h videobuf-dma-sg.c as well.
Signed-off-by: NPawel Osciak <p.osciak@samsung.com>
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

videobuf_pages_to_sg() and videobuf_vmalloc_to_sg() happen to create
a scatterlist element for every page.  However, this is not true for
bus addresses, so other functions shouldn't rely on the length of the
scatter list being equal to nr_pages.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

While analyzing one of the videobuf patches, I noticed that
videobuf_dma_sync is only used internally inside videobuf-dma-sg.
So, let's remove this function, merging the code at __videobuf_dma_sync()
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/videobuf-dma-sg.c: In function ‘__videobuf_mmap_mapper’:
drivers/media/video/videobuf-dma-sg.c:557: warning: ‘size’ may be used uninitialized in this function

The condition where size is floating should never happen, due to the paranoia check,
but a future change at the logic might break it. So, let's just set size to zero and
use it for the paranoia check.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

mmap_mapper should operate on a buffer, not on a complete queue. So let
the videobuf-core find the correct buffer instead of duplicating that
code in each mmap_mapper implementation.

The dma-sg implementation has backwards compatibility code for handling
the V4L1_COMPAT layer. This code is now under the v4L1_COMPAT config option.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

The video_copy_to_user and copy_stream ops are almost identical for all
videobuf memtype variants. All that is needed is to use the new vaddr
op and these functions can be moved into the core, ensuring we have just
one single implementation instead of three.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Rename the .vmalloc op in struct videobuf_qtype_ops to .vaddr. This op returns
the virtual kernel address of a buffer. vaddr is a lot less confusing than
vmalloc since this callback does do any allocations.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

videobuf_alloc() returned a void *. Change to struct videobuf_buffer *
to get better type checking.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Remove the mmap_free callback from struct videobuf_qtype_ops.

All implementations of this callback do the same trivial check: return
-EBUSY if any buffer is mmapped. That can also be tested in the
videobuf core.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Make videobuf pass checkpatch; minor code cleanups.
Signed-off-by: NPawel Osciak <p.osciak@samsung.com>
Reviewed-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

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

The videobuf_queue_ops function vector is not declared constant, but
there's no need for the videobuf layer to ever change it.  Make it const
so that videobuf users can make their operations const without warnings.
Signed-off-by: NJonathan Corbet <corbet@lwn.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

When the image size (bytesperline*height) is not multiple
of PAGE_SIZE, v4l2 rounded the required buffer size to
be multiple of PAGE_SIZE. This prevented user space
to store images directly into userptr buffers which were
not multiple of PAGE_SIZE. This constraint is removed.

The start address is still assumed to be required
page-aligned, ie., when v4l2 allocates mmap buffers,
the offset between different buffers is page-aligned.
Signed-off-by: NTuukka Toivonen <tuukka.o.toivonen@nokia.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

After m68k's task_thread_info() doesn't refer to current,
it's possible to remove sched.h from interrupt.h and not break m68k!
Many thanks to Heiko Carstens for allowing this.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>

* mark struct vm_area_struct::vm_ops as const
* mark vm_ops in AGP code

But leave TTM code alone, something is fishy there with global vm_ops
being used.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

it is better return -ENOMEM than -EIO
Signed-off-by: NFigo.zhang <figo1802@gmail.com>
Signed-off-by: NDouglas Schilling Landgraf <dougsland@redhat.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Change kmalloc()/kfree() to vmalloc()/vfree() for sglist allocation
during videobuf_dma_map() and videobuf_dma_unmap()

High resolution sensors might require too many contiguous pages
to be allocated for sglist by kmalloc() during videobuf_dma_map()
(i.e. 256Kib for 8MP sensor).
In such situations, kmalloc() could face some problem to find the
required free memory. vmalloc() is a safer solution instead, as the
allocated memory does not need to be contiguous.
Signed-off-by: NDavid Cohen <david.cohen@nokia.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Not all architectures provide clear_user_page(), but clear_user_highpage()
is available everywhere at least via the compatibility inline function.

Is this the "trivial patch" that's required for these two drivers?
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Use "scatter gather" instead of "scatter gatter".
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@pengutronix.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

1) Remove a useless initialisation of 'i'

2) Avoid clearing the memory allocated twice (once in 'kcalloc', once
   in 'sg_init_table')

3) Remove a test that can never trigger.  The function returns NULL in
   such a case, so we know that at this point 'pages[0]' != NULL
Signed-off-by: NChristophe Jaillet <jaillet.christophe@wanadoo.fr>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

videobuf-dvb were still using a function that were videobuf-dma-sg
dependent. This patch creates a generic handler for this function. This
way, videobuf-dvb can now work with all videobuf implementations.
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NMichael Krufky <mkrufky@linuxtv.org>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

V4L/DVB (7494): videobuf-dma-sg.c: Avoid NULL dereference and add comment about backwards compatibility
Signed-off-by: NBrandon Philips <bphilips@suse.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

Removed warning message:

 - videobuf-dma-sg.c: In function 'videobuf_dma_unmap':
 - videobuf-dma-sg.c:281: warning: unused variable 'dev'
Signed-off-by: NDouglas Schilling Landgraf <dougsland@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

videobuf-dma-sg does not need to depend on PCI. Switch it to using generic
DMA API, convert all affected drivers, relax Kconfig restriction, improve
compile-time type checking, fix some Coding Style violations while at it.
Signed-off-by: NGuennadi Liakhovetski <g.liakhovetski@pengutronix.de>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

- Static memory is always initialized with 0.
- Replaced in some cases C99 comments for /* */
Signed-off-by: NDouglas Schilling Landgraf <dougsland@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

This helps to identify where vb_lock is being used, and find missusages of the
locks.
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>