Commit Graph

5 Commits

Author SHA1 Message Date
Mauro Carvalho Chehab
d4cae5a500 V4L/DVB (6292): videobuf_core init always require callback implementation
In the past, videobuf_queue_init were used to initialize PCI DMA videobuffers.
This patch renames it, to avoid confusion with the previous kernel API, doing:
	s/videobuf_queue_init/void videobuf_queue_core_init/

Also, the operations is now part of the function parameter. The function will
also add a test if this is defined, otherwise producing BUG.

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-10-10 00:03:14 -03:00
Mauro Carvalho Chehab
5ddff43435 V4L/DVB (6290): remove videobuf_set_pci_ops
Before the videobuf redesign, a procedure for re-using videobuf without PCI
scatter/gather where provided by changing the pci-dependent operations by
other operations.

With the newer approach, those methods are obsolete and can safelly be removed.

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-10-10 00:03:10 -03:00
Maxim Levitsky
9900132f34 V4L/DVB (6268): V4L: Fix a lock inversion in generic videobuf code
videobuf_qbuf takes q->lock, and then calls
q->ops->buf_prepare which by design in all drivers calls
videobuf_iolock which calls videobuf_dma_init_user and this
takes current->mm->mmap_sem

on the other hand if user calls mumap from other thread, sys_munmap
takes current->mm->mmap_sem and videobuf_vm_close takes q->lock

Since this can occur only for V4L2_MEMORY_MMAP buffers, take
current->mm->mmap_sem in qbuf, before q->lock, and don't take
current->mm->mmap_sem videobuf_dma_init_user for those buffers

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
http://thread.gmane.org/gmane.comp.video.video4linux/34978/focus=34981
Reviewed-by: Ricardo Cerqueira <v4l@cerqueira.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-10-10 00:02:58 -03:00
Mauro Carvalho Chehab
851c0c96b2 V4L/DVB (6266): videobuf cleanup: mmap check is common to all videobuf. Make it at core
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
http://thread.gmane.org/gmane.comp.video.video4linux/34978/focus=34981
Reviewed-by: Ricardo Cerqueira <v4l@cerqueira.org>
2007-10-10 00:02:55 -03:00
Mauro Carvalho Chehab
7a7d9a89d0 V4L/DVB (6251): Replace video-buf to a more generic approach
video-buf currently does two different tasks:

- Manages video buffers with a common code that allows
  implementing all the V4L2 different modes of buffering;

- Controls memory allocations

While the first task is generic, the second were written to support PCI DMA
Scatter/Gather needs. The original approach can't even work for those
video capture hardware that don't support scatter/gather.

I did one approach to make it more generic. While the approach worked
fine for vivi driver, it were not generic enough to handle USB needs.

This patch creates two different modules, one containing the generic
video buffer handling (videobuf-core) and another with PCI DMA S/G.
After this patch, it would be simpler to write an USB video-buf and a
non-SG DMA module.

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
http://thread.gmane.org/gmane.comp.video.video4linux/34978/focus=34981
Reviewed-by: Ricardo Cerqueira <v4l@cerqueira.org>
2007-10-09 22:14:55 -03:00