Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
Hi Jon, On Thu, Sep 13, 2012 at 2:54 PM, Jonathan Corbet wrote: > > Well, there is some documentation here: > > https://lwn.net/Articles/447435/ > I thank you for this. It really helped me getting started on videobuf2. > This reminds me that I've always meant to turn it into something to put > into Documentation/. I'll try to get to that soon. > Yes, that's something many of us will appreciate A LOT. Perhaps we could start with some skeleton documentation and then build from there. I maybe naive, but I think that way other developers might add little contributions. Regards, Ezequiel. PS: I wish I had some time to do it myself. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
Hi Jon, On Thu, Sep 13, 2012 at 2:54 PM, Jonathan Corbet cor...@lwn.net wrote: Well, there is some documentation here: https://lwn.net/Articles/447435/ I thank you for this. It really helped me getting started on videobuf2. This reminds me that I've always meant to turn it into something to put into Documentation/. I'll try to get to that soon. Yes, that's something many of us will appreciate A LOT. Perhaps we could start with some skeleton documentation and then build from there. I maybe naive, but I think that way other developers might add little contributions. Regards, Ezequiel. PS: I wish I had some time to do it myself. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
In data giovedì 13 settembre 2012 11:45:31, Jonathan Corbet ha scritto: > On Thu, 13 Sep 2012 17:46:32 +0200 > > Federico Vaga wrote: > > > A few words explaining why this memory handling module is required > > > or > > > beneficial will definitely improve the commit :) > > > > ok, I will write some lines > > In general, all of these patches need *much* better changelogs (i.e. > they need changelogs). What are you doing, and *why* are you doing > it? The future will want to know. I can improve the comment about the ADV7180: it is not clear why I'm removing that functions. (and the memory allocator commit is also in the todo list). The STA2X11_VIP commit, I think is clear, I convert it to use videobu2 and control framework. I can add some extra lines to explain why: because videobuf is obsolete > I'm going to try to look at the actual code, but time isn't something > I have a lot of, still... The actual code is the same of the previous one with yours (plural) suggestions from the RFC submission (few week ago). I did not write anything else. -- Federico Vaga -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
> Well, there is some documentation here: > > https://lwn.net/Articles/447435/ I know this, I learned from this page :) What I'm saying is that I don't know what to write inside the code to make it clearer than now. I think is clear, because if you know the videobuf2, you know what I'm doing in each vb2_mem_ops. I suppose that this is the reason why there are no comments inside the other memory allocator. Maybe I am wrong. -- Federico Vaga -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
On Thu, 13 Sep 2012 17:42:33 +0200 Federico Vaga wrote: > > The header and esp. the source could really do with more > > documentation. It is not at all clear from the code what the > > dma-streaming allocator does and how it differs from other > > allocators. > > The other allocators are not documented and to understand them I read > the code. All the memory allocators reflect a kind of DMA interface: SG > for scatter/gather, contig for choerent and (now) streaming for > streaming. So, I'm not sure to understand what do you think is the > correct way to document a memory allocator; I can write one or two lines > of comment to summarize each function. what do you think? Well, there is some documentation here: https://lwn.net/Articles/447435/ This reminds me that I've always meant to turn it into something to put into Documentation/. I'll try to get to that soon. In general, the fact that a subsystem is insufficiently documented is not a good reason to add more poorly-documented code. We are, after all, trying to make the kernel better over time... Thanks, jon -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
On Thu, 13 Sep 2012 17:46:32 +0200 Federico Vaga wrote: > > A few words explaining why this memory handling module is required or > > beneficial will definitely improve the commit :) > > ok, I will write some lines In general, all of these patches need *much* better changelogs (i.e. they need changelogs). What are you doing, and *why* are you doing it? The future will want to know. I'm going to try to look at the actual code, but time isn't something I have a lot of, still... Thanks, jon -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
> On Thursday, September 13, 2012 3:53 PM Federico Vaga wrote:
> > Signed-off-by: Federico Vaga
>
> A few words explaining why this memory handling module is required or
> beneficial will definitely improve the commit :)
ok, I will write some lines
> > +static void *vb2_dma_streaming_cookie(void *buf_priv)
> > +{
> > + struct vb2_streaming_buf *buf = buf_priv;
> > +
> > + return (void *)buf->dma_handle;
> > +}
>
> Please change this function to:
>
> static void *vb2_dma_streaming_cookie(void *buf_priv)
> {
> struct vb2_streaming_buf *buf = buf_priv;
> return >dma_handle;
> }
>
> and add a following static inline to
> include/media/videobuf2-dma-streaming.h:
>
> static inline dma_addr_t
> vb2_dma_streaming_plane_paddr(struct vb2_buffer *vb, unsigned int
> plane_no) {
> dma_addr_t *dma_addr = vb2_plane_cookie(vb, plane_no);
> return *dma_addr;
> }
>
> Do not use 'cookie' callback directly in the driver, the driver should
> use the above proxy.
>
> The >dma_handle workaround is required for some possible
> configurations with 64bit dma addresses, see commit 472af2b05bdefc.
ACK.
--
Federico Vaga
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
> typo: steaming -> streaming :-) fixed > The header and esp. the source could really do with more > documentation. It is not at all clear from the code what the > dma-streaming allocator does and how it differs from other > allocators. The other allocators are not documented and to understand them I read the code. All the memory allocators reflect a kind of DMA interface: SG for scatter/gather, contig for choerent and (now) streaming for streaming. So, I'm not sure to understand what do you think is the correct way to document a memory allocator; I can write one or two lines of comment to summarize each function. what do you think? -- Federico Vaga -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
On Thu 13 September 2012 15:52:47 Federico Vaga wrote:
> Signed-off-by: Federico Vaga
> ---
> drivers/media/v4l2-core/Kconfig | 5 +
> drivers/media/v4l2-core/Makefile | 1 +
> drivers/media/v4l2-core/videobuf2-dma-streaming.c | 205
> ++
> include/media/videobuf2-dma-streaming.h | 24 +++
> 4 file modificati, 235 inserzioni(+)
> create mode 100644 drivers/media/v4l2-core/videobuf2-dma-streaming.c
> create mode 100644 include/media/videobuf2-dma-streaming.h
>
> diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
> index 0c54e19..60548a7 100644
> --- a/drivers/media/v4l2-core/Kconfig
> +++ b/drivers/media/v4l2-core/Kconfig
> @@ -79,3 +79,8 @@ config VIDEOBUF2_DMA_SG
> #depends on HAS_DMA
> select VIDEOBUF2_CORE
> select VIDEOBUF2_MEMOPS
> +
> +config VIDEOBUF2_DMA_STREAMING
> + select VIDEOBUF2_CORE
> + select VIDEOBUF2_MEMOPS
> + tristate
> diff --git a/drivers/media/v4l2-core/Makefile
> b/drivers/media/v4l2-core/Makefile
> index c2d61d4..0b2756f 100644
> --- a/drivers/media/v4l2-core/Makefile
> +++ b/drivers/media/v4l2-core/Makefile
> @@ -28,6 +28,7 @@ obj-$(CONFIG_VIDEOBUF2_MEMOPS) += videobuf2-memops.o
> obj-$(CONFIG_VIDEOBUF2_VMALLOC) += videobuf2-vmalloc.o
> obj-$(CONFIG_VIDEOBUF2_DMA_CONTIG) += videobuf2-dma-contig.o
> obj-$(CONFIG_VIDEOBUF2_DMA_SG) += videobuf2-dma-sg.o
> +obj-$(CONFIG_VIDEOBUF2_DMA_STREAMING) += videobuf2-dma-streaming.o
>
> ccflags-y += -I$(srctree)/drivers/media/dvb-core
> ccflags-y += -I$(srctree)/drivers/media/dvb-frontends
> diff --git a/drivers/media/v4l2-core/videobuf2-dma-streaming.c
> b/drivers/media/v4l2-core/videobuf2-dma-streaming.c
> new file mode 100644
> index 000..23475a6
> --- /dev/null
> +++ b/drivers/media/v4l2-core/videobuf2-dma-streaming.c
> @@ -0,0 +1,205 @@
> +/*
> + * videobuf2-dma-streaming.c - DMA streaming memory allocator for videobuf2
> + *
> + * Copyright (C) 2012 Federico Vaga
> + * *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include
> +#include
> +#include
> +#include
> +
> +#include
> +#include
> +#include
> +
> +struct vb2_streaming_conf {
> + struct device *dev;
> +};
> +struct vb2_streaming_buf {
> + struct vb2_streaming_conf *conf;
> + void*vaddr;
> +
> + dma_addr_t dma_handle;
> +
> + unsigned long size;
> + struct vm_area_struct *vma;
> +
> + atomic_trefcount;
> + struct vb2_vmarea_handler handler;
> +};
> +
> +static void vb2_dma_streaming_put(void *buf_priv)
> +{
> + struct vb2_streaming_buf *buf = buf_priv;
> +
> + if (atomic_dec_and_test(>refcount)) {
> + dma_unmap_single(buf->conf->dev, buf->dma_handle, buf->size,
> + DMA_FROM_DEVICE);
> + free_pages_exact(buf->vaddr, buf->size);
> + kfree(buf);
> + }
> +
> +}
> +
> +static void *vb2_dma_streaming_alloc(void *alloc_ctx, unsigned long size)
> +{
> + struct vb2_streaming_conf *conf = alloc_ctx;
> + struct vb2_streaming_buf *buf;
> + int err;
> +
> + buf = kzalloc(sizeof *buf, GFP_KERNEL);
> + if (!buf)
> + return ERR_PTR(-ENOMEM);
> + buf->vaddr = alloc_pages_exact(size, GFP_KERNEL | GFP_DMA);
> + if (!buf->vaddr) {
> + err = -ENOMEM;
> + goto out;
> + }
> + buf->dma_handle = dma_map_single(conf->dev, buf->vaddr, size,
> + DMA_FROM_DEVICE);
> + err = dma_mapping_error(conf->dev, buf->dma_handle);
> + if (err) {
> + dev_err(conf->dev, "dma_map_single failed\n");
> +
> + free_pages_exact(buf->vaddr, size);
> + buf->vaddr = NULL;
> + goto out_pages;
> + }
> + buf->conf = conf;
> + buf->size = size;
> + buf->handler.refcount = >refcount;
> + buf->handler.put = vb2_dma_streaming_put;
> + buf->handler.arg = buf;
> +
> + atomic_inc(>refcount);
> + return buf;
> +
> +out_pages:
> + free_pages_exact(buf->vaddr, buf->size);
> +out:
> + kfree(buf);
> + return ERR_PTR(err);
> +}
> +
> +static void *vb2_dma_streaming_cookie(void *buf_priv)
> +{
> + struct vb2_streaming_buf *buf = buf_priv;
> +
> + return (void *)buf->dma_handle;
> +}
> +
> +static void *vb2_dma_streaming_vaddr(void *buf_priv)
> +{
> + struct vb2_streaming_buf *buf = buf_priv;
> +
> + if (!buf)
> + return NULL;
> + return buf->vaddr;
> +}
> +
> +static unsigned int vb2_dma_streaming_num_users(void *buf_priv)
> +{
> + struct vb2_streaming_buf *buf = buf_priv;
> +
> + return atomic_read(>refcount);
> +}
> +
> +static int
RE: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
Hello,
On Thursday, September 13, 2012 3:53 PM Federico Vaga wrote:
> Signed-off-by: Federico Vaga
A few words explaining why this memory handling module is required or
beneficial will
definitely improve the commit :)
> ---
> drivers/media/v4l2-core/Kconfig | 5 +
> drivers/media/v4l2-core/Makefile | 1 +
> drivers/media/v4l2-core/videobuf2-dma-streaming.c | 205
> ++
> include/media/videobuf2-dma-streaming.h | 24 +++
> 4 file modificati, 235 inserzioni(+)
> create mode 100644 drivers/media/v4l2-core/videobuf2-dma-streaming.c
> create mode 100644 include/media/videobuf2-dma-streaming.h
>
> diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
> index 0c54e19..60548a7 100644
> --- a/drivers/media/v4l2-core/Kconfig
> +++ b/drivers/media/v4l2-core/Kconfig
> @@ -79,3 +79,8 @@ config VIDEOBUF2_DMA_SG
> #depends on HAS_DMA
> select VIDEOBUF2_CORE
> select VIDEOBUF2_MEMOPS
> +
> +config VIDEOBUF2_DMA_STREAMING
> + select VIDEOBUF2_CORE
> + select VIDEOBUF2_MEMOPS
> + tristate
> diff --git a/drivers/media/v4l2-core/Makefile
> b/drivers/media/v4l2-core/Makefile
> index c2d61d4..0b2756f 100644
> --- a/drivers/media/v4l2-core/Makefile
> +++ b/drivers/media/v4l2-core/Makefile
> @@ -28,6 +28,7 @@ obj-$(CONFIG_VIDEOBUF2_MEMOPS) += videobuf2-memops.o
> obj-$(CONFIG_VIDEOBUF2_VMALLOC) += videobuf2-vmalloc.o
> obj-$(CONFIG_VIDEOBUF2_DMA_CONTIG) += videobuf2-dma-contig.o
> obj-$(CONFIG_VIDEOBUF2_DMA_SG) += videobuf2-dma-sg.o
> +obj-$(CONFIG_VIDEOBUF2_DMA_STREAMING) += videobuf2-dma-streaming.o
>
> ccflags-y += -I$(srctree)/drivers/media/dvb-core
> ccflags-y += -I$(srctree)/drivers/media/dvb-frontends
> diff --git a/drivers/media/v4l2-core/videobuf2-dma-streaming.c
> b/drivers/media/v4l2-
> core/videobuf2-dma-streaming.c
> new file mode 100644
> index 000..23475a6
> --- /dev/null
> +++ b/drivers/media/v4l2-core/videobuf2-dma-streaming.c
> @@ -0,0 +1,205 @@
> +/*
> + * videobuf2-dma-streaming.c - DMA streaming memory allocator for videobuf2
> + *
> + * Copyright (C) 2012 Federico Vaga
> + * *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include
> +#include
> +#include
> +#include
> +
> +#include
> +#include
> +#include
> +
> +struct vb2_streaming_conf {
> + struct device *dev;
> +};
> +struct vb2_streaming_buf {
> + struct vb2_streaming_conf *conf;
> + void*vaddr;
> +
> + dma_addr_t dma_handle;
> +
> + unsigned long size;
> + struct vm_area_struct *vma;
> +
> + atomic_trefcount;
> + struct vb2_vmarea_handler handler;
> +};
> +
> +static void vb2_dma_streaming_put(void *buf_priv)
> +{
> + struct vb2_streaming_buf *buf = buf_priv;
> +
> + if (atomic_dec_and_test(>refcount)) {
> + dma_unmap_single(buf->conf->dev, buf->dma_handle, buf->size,
> + DMA_FROM_DEVICE);
> + free_pages_exact(buf->vaddr, buf->size);
> + kfree(buf);
> + }
> +
> +}
> +
> +static void *vb2_dma_streaming_alloc(void *alloc_ctx, unsigned long size)
> +{
> + struct vb2_streaming_conf *conf = alloc_ctx;
> + struct vb2_streaming_buf *buf;
> + int err;
> +
> + buf = kzalloc(sizeof *buf, GFP_KERNEL);
> + if (!buf)
> + return ERR_PTR(-ENOMEM);
> + buf->vaddr = alloc_pages_exact(size, GFP_KERNEL | GFP_DMA);
> + if (!buf->vaddr) {
> + err = -ENOMEM;
> + goto out;
> + }
> + buf->dma_handle = dma_map_single(conf->dev, buf->vaddr, size,
> + DMA_FROM_DEVICE);
> + err = dma_mapping_error(conf->dev, buf->dma_handle);
> + if (err) {
> + dev_err(conf->dev, "dma_map_single failed\n");
> +
> + free_pages_exact(buf->vaddr, size);
> + buf->vaddr = NULL;
> + goto out_pages;
> + }
> + buf->conf = conf;
> + buf->size = size;
> + buf->handler.refcount = >refcount;
> + buf->handler.put = vb2_dma_streaming_put;
> + buf->handler.arg = buf;
> +
> + atomic_inc(>refcount);
> + return buf;
> +
> +out_pages:
> + free_pages_exact(buf->vaddr, buf->size);
> +out:
> + kfree(buf);
> + return ERR_PTR(err);
> +}
> +
> +static void *vb2_dma_streaming_cookie(void *buf_priv)
> +{
> + struct vb2_streaming_buf *buf = buf_priv;
> +
> + return (void *)buf->dma_handle;
> +}
Please change this function to:
static void *vb2_dma_streaming_cookie(void *buf_priv)
{
struct vb2_streaming_buf *buf = buf_priv;
return >dma_handle;
}
and add a following static inline to include/media/videobuf2-dma-streaming.h:
static inline
[PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
Signed-off-by: Federico Vaga
---
drivers/media/v4l2-core/Kconfig | 5 +
drivers/media/v4l2-core/Makefile | 1 +
drivers/media/v4l2-core/videobuf2-dma-streaming.c | 205 ++
include/media/videobuf2-dma-streaming.h | 24 +++
4 file modificati, 235 inserzioni(+)
create mode 100644 drivers/media/v4l2-core/videobuf2-dma-streaming.c
create mode 100644 include/media/videobuf2-dma-streaming.h
diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
index 0c54e19..60548a7 100644
--- a/drivers/media/v4l2-core/Kconfig
+++ b/drivers/media/v4l2-core/Kconfig
@@ -79,3 +79,8 @@ config VIDEOBUF2_DMA_SG
#depends on HAS_DMA
select VIDEOBUF2_CORE
select VIDEOBUF2_MEMOPS
+
+config VIDEOBUF2_DMA_STREAMING
+ select VIDEOBUF2_CORE
+ select VIDEOBUF2_MEMOPS
+ tristate
diff --git a/drivers/media/v4l2-core/Makefile b/drivers/media/v4l2-core/Makefile
index c2d61d4..0b2756f 100644
--- a/drivers/media/v4l2-core/Makefile
+++ b/drivers/media/v4l2-core/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_VIDEOBUF2_MEMOPS) += videobuf2-memops.o
obj-$(CONFIG_VIDEOBUF2_VMALLOC) += videobuf2-vmalloc.o
obj-$(CONFIG_VIDEOBUF2_DMA_CONTIG) += videobuf2-dma-contig.o
obj-$(CONFIG_VIDEOBUF2_DMA_SG) += videobuf2-dma-sg.o
+obj-$(CONFIG_VIDEOBUF2_DMA_STREAMING) += videobuf2-dma-streaming.o
ccflags-y += -I$(srctree)/drivers/media/dvb-core
ccflags-y += -I$(srctree)/drivers/media/dvb-frontends
diff --git a/drivers/media/v4l2-core/videobuf2-dma-streaming.c
b/drivers/media/v4l2-core/videobuf2-dma-streaming.c
new file mode 100644
index 000..23475a6
--- /dev/null
+++ b/drivers/media/v4l2-core/videobuf2-dma-streaming.c
@@ -0,0 +1,205 @@
+/*
+ * videobuf2-dma-streaming.c - DMA streaming memory allocator for videobuf2
+ *
+ * Copyright (C) 2012 Federico Vaga
+ * *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include
+#include
+#include
+#include
+
+#include
+#include
+#include
+
+struct vb2_streaming_conf {
+ struct device *dev;
+};
+struct vb2_streaming_buf {
+ struct vb2_streaming_conf *conf;
+ void*vaddr;
+
+ dma_addr_t dma_handle;
+
+ unsigned long size;
+ struct vm_area_struct *vma;
+
+ atomic_trefcount;
+ struct vb2_vmarea_handler handler;
+};
+
+static void vb2_dma_streaming_put(void *buf_priv)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+
+ if (atomic_dec_and_test(>refcount)) {
+ dma_unmap_single(buf->conf->dev, buf->dma_handle, buf->size,
+DMA_FROM_DEVICE);
+ free_pages_exact(buf->vaddr, buf->size);
+ kfree(buf);
+ }
+
+}
+
+static void *vb2_dma_streaming_alloc(void *alloc_ctx, unsigned long size)
+{
+ struct vb2_streaming_conf *conf = alloc_ctx;
+ struct vb2_streaming_buf *buf;
+ int err;
+
+ buf = kzalloc(sizeof *buf, GFP_KERNEL);
+ if (!buf)
+ return ERR_PTR(-ENOMEM);
+ buf->vaddr = alloc_pages_exact(size, GFP_KERNEL | GFP_DMA);
+ if (!buf->vaddr) {
+ err = -ENOMEM;
+ goto out;
+ }
+ buf->dma_handle = dma_map_single(conf->dev, buf->vaddr, size,
+DMA_FROM_DEVICE);
+ err = dma_mapping_error(conf->dev, buf->dma_handle);
+ if (err) {
+ dev_err(conf->dev, "dma_map_single failed\n");
+
+ free_pages_exact(buf->vaddr, size);
+ buf->vaddr = NULL;
+ goto out_pages;
+ }
+ buf->conf = conf;
+ buf->size = size;
+ buf->handler.refcount = >refcount;
+ buf->handler.put = vb2_dma_streaming_put;
+ buf->handler.arg = buf;
+
+ atomic_inc(>refcount);
+ return buf;
+
+out_pages:
+ free_pages_exact(buf->vaddr, buf->size);
+out:
+ kfree(buf);
+ return ERR_PTR(err);
+}
+
+static void *vb2_dma_streaming_cookie(void *buf_priv)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+
+ return (void *)buf->dma_handle;
+}
+
+static void *vb2_dma_streaming_vaddr(void *buf_priv)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+
+ if (!buf)
+ return NULL;
+ return buf->vaddr;
+}
+
+static unsigned int vb2_dma_streaming_num_users(void *buf_priv)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+
+ return atomic_read(>refcount);
+}
+
+static int vb2_dma_streaming_mmap(void *buf_priv, struct vm_area_struct *vma)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+ unsigned long pos, start = vma->vm_start;
+ unsigned long size;
+ struct page *page;
+ int err;
+
+ /* Try to remap
[PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
Signed-off-by: Federico Vaga federico.v...@gmail.com
---
drivers/media/v4l2-core/Kconfig | 5 +
drivers/media/v4l2-core/Makefile | 1 +
drivers/media/v4l2-core/videobuf2-dma-streaming.c | 205 ++
include/media/videobuf2-dma-streaming.h | 24 +++
4 file modificati, 235 inserzioni(+)
create mode 100644 drivers/media/v4l2-core/videobuf2-dma-streaming.c
create mode 100644 include/media/videobuf2-dma-streaming.h
diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
index 0c54e19..60548a7 100644
--- a/drivers/media/v4l2-core/Kconfig
+++ b/drivers/media/v4l2-core/Kconfig
@@ -79,3 +79,8 @@ config VIDEOBUF2_DMA_SG
#depends on HAS_DMA
select VIDEOBUF2_CORE
select VIDEOBUF2_MEMOPS
+
+config VIDEOBUF2_DMA_STREAMING
+ select VIDEOBUF2_CORE
+ select VIDEOBUF2_MEMOPS
+ tristate
diff --git a/drivers/media/v4l2-core/Makefile b/drivers/media/v4l2-core/Makefile
index c2d61d4..0b2756f 100644
--- a/drivers/media/v4l2-core/Makefile
+++ b/drivers/media/v4l2-core/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_VIDEOBUF2_MEMOPS) += videobuf2-memops.o
obj-$(CONFIG_VIDEOBUF2_VMALLOC) += videobuf2-vmalloc.o
obj-$(CONFIG_VIDEOBUF2_DMA_CONTIG) += videobuf2-dma-contig.o
obj-$(CONFIG_VIDEOBUF2_DMA_SG) += videobuf2-dma-sg.o
+obj-$(CONFIG_VIDEOBUF2_DMA_STREAMING) += videobuf2-dma-streaming.o
ccflags-y += -I$(srctree)/drivers/media/dvb-core
ccflags-y += -I$(srctree)/drivers/media/dvb-frontends
diff --git a/drivers/media/v4l2-core/videobuf2-dma-streaming.c
b/drivers/media/v4l2-core/videobuf2-dma-streaming.c
new file mode 100644
index 000..23475a6
--- /dev/null
+++ b/drivers/media/v4l2-core/videobuf2-dma-streaming.c
@@ -0,0 +1,205 @@
+/*
+ * videobuf2-dma-streaming.c - DMA streaming memory allocator for videobuf2
+ *
+ * Copyright (C) 2012 Federico Vaga federico.v...@gmail.com
+ * *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include linux/module.h
+#include linux/slab.h
+#include linux/pagemap.h
+#include linux/dma-mapping.h
+
+#include media/videobuf2-core.h
+#include media/videobuf2-dma-streaming.h
+#include media/videobuf2-memops.h
+
+struct vb2_streaming_conf {
+ struct device *dev;
+};
+struct vb2_streaming_buf {
+ struct vb2_streaming_conf *conf;
+ void*vaddr;
+
+ dma_addr_t dma_handle;
+
+ unsigned long size;
+ struct vm_area_struct *vma;
+
+ atomic_trefcount;
+ struct vb2_vmarea_handler handler;
+};
+
+static void vb2_dma_streaming_put(void *buf_priv)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+
+ if (atomic_dec_and_test(buf-refcount)) {
+ dma_unmap_single(buf-conf-dev, buf-dma_handle, buf-size,
+DMA_FROM_DEVICE);
+ free_pages_exact(buf-vaddr, buf-size);
+ kfree(buf);
+ }
+
+}
+
+static void *vb2_dma_streaming_alloc(void *alloc_ctx, unsigned long size)
+{
+ struct vb2_streaming_conf *conf = alloc_ctx;
+ struct vb2_streaming_buf *buf;
+ int err;
+
+ buf = kzalloc(sizeof *buf, GFP_KERNEL);
+ if (!buf)
+ return ERR_PTR(-ENOMEM);
+ buf-vaddr = alloc_pages_exact(size, GFP_KERNEL | GFP_DMA);
+ if (!buf-vaddr) {
+ err = -ENOMEM;
+ goto out;
+ }
+ buf-dma_handle = dma_map_single(conf-dev, buf-vaddr, size,
+DMA_FROM_DEVICE);
+ err = dma_mapping_error(conf-dev, buf-dma_handle);
+ if (err) {
+ dev_err(conf-dev, dma_map_single failed\n);
+
+ free_pages_exact(buf-vaddr, size);
+ buf-vaddr = NULL;
+ goto out_pages;
+ }
+ buf-conf = conf;
+ buf-size = size;
+ buf-handler.refcount = buf-refcount;
+ buf-handler.put = vb2_dma_streaming_put;
+ buf-handler.arg = buf;
+
+ atomic_inc(buf-refcount);
+ return buf;
+
+out_pages:
+ free_pages_exact(buf-vaddr, buf-size);
+out:
+ kfree(buf);
+ return ERR_PTR(err);
+}
+
+static void *vb2_dma_streaming_cookie(void *buf_priv)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+
+ return (void *)buf-dma_handle;
+}
+
+static void *vb2_dma_streaming_vaddr(void *buf_priv)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+
+ if (!buf)
+ return NULL;
+ return buf-vaddr;
+}
+
+static unsigned int vb2_dma_streaming_num_users(void *buf_priv)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+
+ return atomic_read(buf-refcount);
+}
+
+static int vb2_dma_streaming_mmap(void *buf_priv, struct vm_area_struct *vma)
+{
+ struct vb2_streaming_buf
RE: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
Hello,
On Thursday, September 13, 2012 3:53 PM Federico Vaga wrote:
Signed-off-by: Federico Vaga federico.v...@gmail.com
A few words explaining why this memory handling module is required or
beneficial will
definitely improve the commit :)
---
drivers/media/v4l2-core/Kconfig | 5 +
drivers/media/v4l2-core/Makefile | 1 +
drivers/media/v4l2-core/videobuf2-dma-streaming.c | 205
++
include/media/videobuf2-dma-streaming.h | 24 +++
4 file modificati, 235 inserzioni(+)
create mode 100644 drivers/media/v4l2-core/videobuf2-dma-streaming.c
create mode 100644 include/media/videobuf2-dma-streaming.h
diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
index 0c54e19..60548a7 100644
--- a/drivers/media/v4l2-core/Kconfig
+++ b/drivers/media/v4l2-core/Kconfig
@@ -79,3 +79,8 @@ config VIDEOBUF2_DMA_SG
#depends on HAS_DMA
select VIDEOBUF2_CORE
select VIDEOBUF2_MEMOPS
+
+config VIDEOBUF2_DMA_STREAMING
+ select VIDEOBUF2_CORE
+ select VIDEOBUF2_MEMOPS
+ tristate
diff --git a/drivers/media/v4l2-core/Makefile
b/drivers/media/v4l2-core/Makefile
index c2d61d4..0b2756f 100644
--- a/drivers/media/v4l2-core/Makefile
+++ b/drivers/media/v4l2-core/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_VIDEOBUF2_MEMOPS) += videobuf2-memops.o
obj-$(CONFIG_VIDEOBUF2_VMALLOC) += videobuf2-vmalloc.o
obj-$(CONFIG_VIDEOBUF2_DMA_CONTIG) += videobuf2-dma-contig.o
obj-$(CONFIG_VIDEOBUF2_DMA_SG) += videobuf2-dma-sg.o
+obj-$(CONFIG_VIDEOBUF2_DMA_STREAMING) += videobuf2-dma-streaming.o
ccflags-y += -I$(srctree)/drivers/media/dvb-core
ccflags-y += -I$(srctree)/drivers/media/dvb-frontends
diff --git a/drivers/media/v4l2-core/videobuf2-dma-streaming.c
b/drivers/media/v4l2-
core/videobuf2-dma-streaming.c
new file mode 100644
index 000..23475a6
--- /dev/null
+++ b/drivers/media/v4l2-core/videobuf2-dma-streaming.c
@@ -0,0 +1,205 @@
+/*
+ * videobuf2-dma-streaming.c - DMA streaming memory allocator for videobuf2
+ *
+ * Copyright (C) 2012 Federico Vaga federico.v...@gmail.com
+ * *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include linux/module.h
+#include linux/slab.h
+#include linux/pagemap.h
+#include linux/dma-mapping.h
+
+#include media/videobuf2-core.h
+#include media/videobuf2-dma-streaming.h
+#include media/videobuf2-memops.h
+
+struct vb2_streaming_conf {
+ struct device *dev;
+};
+struct vb2_streaming_buf {
+ struct vb2_streaming_conf *conf;
+ void*vaddr;
+
+ dma_addr_t dma_handle;
+
+ unsigned long size;
+ struct vm_area_struct *vma;
+
+ atomic_trefcount;
+ struct vb2_vmarea_handler handler;
+};
+
+static void vb2_dma_streaming_put(void *buf_priv)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+
+ if (atomic_dec_and_test(buf-refcount)) {
+ dma_unmap_single(buf-conf-dev, buf-dma_handle, buf-size,
+ DMA_FROM_DEVICE);
+ free_pages_exact(buf-vaddr, buf-size);
+ kfree(buf);
+ }
+
+}
+
+static void *vb2_dma_streaming_alloc(void *alloc_ctx, unsigned long size)
+{
+ struct vb2_streaming_conf *conf = alloc_ctx;
+ struct vb2_streaming_buf *buf;
+ int err;
+
+ buf = kzalloc(sizeof *buf, GFP_KERNEL);
+ if (!buf)
+ return ERR_PTR(-ENOMEM);
+ buf-vaddr = alloc_pages_exact(size, GFP_KERNEL | GFP_DMA);
+ if (!buf-vaddr) {
+ err = -ENOMEM;
+ goto out;
+ }
+ buf-dma_handle = dma_map_single(conf-dev, buf-vaddr, size,
+ DMA_FROM_DEVICE);
+ err = dma_mapping_error(conf-dev, buf-dma_handle);
+ if (err) {
+ dev_err(conf-dev, dma_map_single failed\n);
+
+ free_pages_exact(buf-vaddr, size);
+ buf-vaddr = NULL;
+ goto out_pages;
+ }
+ buf-conf = conf;
+ buf-size = size;
+ buf-handler.refcount = buf-refcount;
+ buf-handler.put = vb2_dma_streaming_put;
+ buf-handler.arg = buf;
+
+ atomic_inc(buf-refcount);
+ return buf;
+
+out_pages:
+ free_pages_exact(buf-vaddr, buf-size);
+out:
+ kfree(buf);
+ return ERR_PTR(err);
+}
+
+static void *vb2_dma_streaming_cookie(void *buf_priv)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+
+ return (void *)buf-dma_handle;
+}
Please change this function to:
static void *vb2_dma_streaming_cookie(void *buf_priv)
{
struct vb2_streaming_buf *buf = buf_priv;
return buf-dma_handle;
}
and add a following static inline to
Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
On Thu 13 September 2012 15:52:47 Federico Vaga wrote:
Signed-off-by: Federico Vaga federico.v...@gmail.com
---
drivers/media/v4l2-core/Kconfig | 5 +
drivers/media/v4l2-core/Makefile | 1 +
drivers/media/v4l2-core/videobuf2-dma-streaming.c | 205
++
include/media/videobuf2-dma-streaming.h | 24 +++
4 file modificati, 235 inserzioni(+)
create mode 100644 drivers/media/v4l2-core/videobuf2-dma-streaming.c
create mode 100644 include/media/videobuf2-dma-streaming.h
diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
index 0c54e19..60548a7 100644
--- a/drivers/media/v4l2-core/Kconfig
+++ b/drivers/media/v4l2-core/Kconfig
@@ -79,3 +79,8 @@ config VIDEOBUF2_DMA_SG
#depends on HAS_DMA
select VIDEOBUF2_CORE
select VIDEOBUF2_MEMOPS
+
+config VIDEOBUF2_DMA_STREAMING
+ select VIDEOBUF2_CORE
+ select VIDEOBUF2_MEMOPS
+ tristate
diff --git a/drivers/media/v4l2-core/Makefile
b/drivers/media/v4l2-core/Makefile
index c2d61d4..0b2756f 100644
--- a/drivers/media/v4l2-core/Makefile
+++ b/drivers/media/v4l2-core/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_VIDEOBUF2_MEMOPS) += videobuf2-memops.o
obj-$(CONFIG_VIDEOBUF2_VMALLOC) += videobuf2-vmalloc.o
obj-$(CONFIG_VIDEOBUF2_DMA_CONTIG) += videobuf2-dma-contig.o
obj-$(CONFIG_VIDEOBUF2_DMA_SG) += videobuf2-dma-sg.o
+obj-$(CONFIG_VIDEOBUF2_DMA_STREAMING) += videobuf2-dma-streaming.o
ccflags-y += -I$(srctree)/drivers/media/dvb-core
ccflags-y += -I$(srctree)/drivers/media/dvb-frontends
diff --git a/drivers/media/v4l2-core/videobuf2-dma-streaming.c
b/drivers/media/v4l2-core/videobuf2-dma-streaming.c
new file mode 100644
index 000..23475a6
--- /dev/null
+++ b/drivers/media/v4l2-core/videobuf2-dma-streaming.c
@@ -0,0 +1,205 @@
+/*
+ * videobuf2-dma-streaming.c - DMA streaming memory allocator for videobuf2
+ *
+ * Copyright (C) 2012 Federico Vaga federico.v...@gmail.com
+ * *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include linux/module.h
+#include linux/slab.h
+#include linux/pagemap.h
+#include linux/dma-mapping.h
+
+#include media/videobuf2-core.h
+#include media/videobuf2-dma-streaming.h
+#include media/videobuf2-memops.h
+
+struct vb2_streaming_conf {
+ struct device *dev;
+};
+struct vb2_streaming_buf {
+ struct vb2_streaming_conf *conf;
+ void*vaddr;
+
+ dma_addr_t dma_handle;
+
+ unsigned long size;
+ struct vm_area_struct *vma;
+
+ atomic_trefcount;
+ struct vb2_vmarea_handler handler;
+};
+
+static void vb2_dma_streaming_put(void *buf_priv)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+
+ if (atomic_dec_and_test(buf-refcount)) {
+ dma_unmap_single(buf-conf-dev, buf-dma_handle, buf-size,
+ DMA_FROM_DEVICE);
+ free_pages_exact(buf-vaddr, buf-size);
+ kfree(buf);
+ }
+
+}
+
+static void *vb2_dma_streaming_alloc(void *alloc_ctx, unsigned long size)
+{
+ struct vb2_streaming_conf *conf = alloc_ctx;
+ struct vb2_streaming_buf *buf;
+ int err;
+
+ buf = kzalloc(sizeof *buf, GFP_KERNEL);
+ if (!buf)
+ return ERR_PTR(-ENOMEM);
+ buf-vaddr = alloc_pages_exact(size, GFP_KERNEL | GFP_DMA);
+ if (!buf-vaddr) {
+ err = -ENOMEM;
+ goto out;
+ }
+ buf-dma_handle = dma_map_single(conf-dev, buf-vaddr, size,
+ DMA_FROM_DEVICE);
+ err = dma_mapping_error(conf-dev, buf-dma_handle);
+ if (err) {
+ dev_err(conf-dev, dma_map_single failed\n);
+
+ free_pages_exact(buf-vaddr, size);
+ buf-vaddr = NULL;
+ goto out_pages;
+ }
+ buf-conf = conf;
+ buf-size = size;
+ buf-handler.refcount = buf-refcount;
+ buf-handler.put = vb2_dma_streaming_put;
+ buf-handler.arg = buf;
+
+ atomic_inc(buf-refcount);
+ return buf;
+
+out_pages:
+ free_pages_exact(buf-vaddr, buf-size);
+out:
+ kfree(buf);
+ return ERR_PTR(err);
+}
+
+static void *vb2_dma_streaming_cookie(void *buf_priv)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+
+ return (void *)buf-dma_handle;
+}
+
+static void *vb2_dma_streaming_vaddr(void *buf_priv)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+
+ if (!buf)
+ return NULL;
+ return buf-vaddr;
+}
+
+static unsigned int vb2_dma_streaming_num_users(void *buf_priv)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+
+ return atomic_read(buf-refcount);
+}
+
+static int
Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
typo: steaming - streaming :-) fixed The header and esp. the source could really do with more documentation. It is not at all clear from the code what the dma-streaming allocator does and how it differs from other allocators. The other allocators are not documented and to understand them I read the code. All the memory allocators reflect a kind of DMA interface: SG for scatter/gather, contig for choerent and (now) streaming for streaming. So, I'm not sure to understand what do you think is the correct way to document a memory allocator; I can write one or two lines of comment to summarize each function. what do you think? -- Federico Vaga -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
On Thursday, September 13, 2012 3:53 PM Federico Vaga wrote:
Signed-off-by: Federico Vaga federico.v...@gmail.com
A few words explaining why this memory handling module is required or
beneficial will definitely improve the commit :)
ok, I will write some lines
+static void *vb2_dma_streaming_cookie(void *buf_priv)
+{
+ struct vb2_streaming_buf *buf = buf_priv;
+
+ return (void *)buf-dma_handle;
+}
Please change this function to:
static void *vb2_dma_streaming_cookie(void *buf_priv)
{
struct vb2_streaming_buf *buf = buf_priv;
return buf-dma_handle;
}
and add a following static inline to
include/media/videobuf2-dma-streaming.h:
static inline dma_addr_t
vb2_dma_streaming_plane_paddr(struct vb2_buffer *vb, unsigned int
plane_no) {
dma_addr_t *dma_addr = vb2_plane_cookie(vb, plane_no);
return *dma_addr;
}
Do not use 'cookie' callback directly in the driver, the driver should
use the above proxy.
The buf-dma_handle workaround is required for some possible
configurations with 64bit dma addresses, see commit 472af2b05bdefc.
ACK.
--
Federico Vaga
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
On Thu, 13 Sep 2012 17:46:32 +0200 Federico Vaga federico.v...@gmail.com wrote: A few words explaining why this memory handling module is required or beneficial will definitely improve the commit :) ok, I will write some lines In general, all of these patches need *much* better changelogs (i.e. they need changelogs). What are you doing, and *why* are you doing it? The future will want to know. I'm going to try to look at the actual code, but time isn't something I have a lot of, still... Thanks, jon -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
On Thu, 13 Sep 2012 17:42:33 +0200 Federico Vaga federico.v...@gmail.com wrote: The header and esp. the source could really do with more documentation. It is not at all clear from the code what the dma-streaming allocator does and how it differs from other allocators. The other allocators are not documented and to understand them I read the code. All the memory allocators reflect a kind of DMA interface: SG for scatter/gather, contig for choerent and (now) streaming for streaming. So, I'm not sure to understand what do you think is the correct way to document a memory allocator; I can write one or two lines of comment to summarize each function. what do you think? Well, there is some documentation here: https://lwn.net/Articles/447435/ This reminds me that I've always meant to turn it into something to put into Documentation/. I'll try to get to that soon. In general, the fact that a subsystem is insufficiently documented is not a good reason to add more poorly-documented code. We are, after all, trying to make the kernel better over time... Thanks, jon -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
Well, there is some documentation here: https://lwn.net/Articles/447435/ I know this, I learned from this page :) What I'm saying is that I don't know what to write inside the code to make it clearer than now. I think is clear, because if you know the videobuf2, you know what I'm doing in each vb2_mem_ops. I suppose that this is the reason why there are no comments inside the other memory allocator. Maybe I am wrong. -- Federico Vaga -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 3/4] videobuf2-dma-streaming: new videobuf2 memory allocator
In data giovedì 13 settembre 2012 11:45:31, Jonathan Corbet ha scritto: On Thu, 13 Sep 2012 17:46:32 +0200 Federico Vaga federico.v...@gmail.com wrote: A few words explaining why this memory handling module is required or beneficial will definitely improve the commit :) ok, I will write some lines In general, all of these patches need *much* better changelogs (i.e. they need changelogs). What are you doing, and *why* are you doing it? The future will want to know. I can improve the comment about the ADV7180: it is not clear why I'm removing that functions. (and the memory allocator commit is also in the todo list). The STA2X11_VIP commit, I think is clear, I convert it to use videobu2 and control framework. I can add some extra lines to explain why: because videobuf is obsolete I'm going to try to look at the actual code, but time isn't something I have a lot of, still... The actual code is the same of the previous one with yours (plural) suggestions from the RFC submission (few week ago). I did not write anything else. -- Federico Vaga -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
