| Message ID | 1344958496-9373-2-git-send-email-t.stanislaws@samsung.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue August 14 2012 17:34:31 Tomasz Stanislawski wrote: > From: Sumit Semwal <sumit.semwal@ti.com> > > Adds DMABUF memory type to v4l framework. Also adds the related file > descriptor in v4l2_plane and v4l2_buffer. > > Signed-off-by: Tomasz Stanislawski <t.stanislaws@samsung.com> > [original work in the PoC for buffer sharing] > Signed-off-by: Sumit Semwal <sumit.semwal@ti.com> > Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org> > Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > --- > drivers/media/video/v4l2-compat-ioctl32.c | 18 ++++++++++++++++++ > drivers/media/video/v4l2-ioctl.c | 1 + > include/linux/videodev2.h | 7 +++++++ > 3 files changed, 26 insertions(+) > > diff --git a/drivers/media/video/v4l2-compat-ioctl32.c b/drivers/media/video/v4l2-compat-ioctl32.c > index 9ebd5c5..a2e0549 100644 > --- a/drivers/media/video/v4l2-compat-ioctl32.c > +++ b/drivers/media/video/v4l2-compat-ioctl32.c > @@ -304,6 +304,7 @@ struct v4l2_plane32 { > union { > __u32 mem_offset; > compat_long_t userptr; > + __u32 fd; Shouldn't this be int? > } m; > __u32 data_offset; > __u32 reserved[11]; > @@ -325,6 +326,7 @@ struct v4l2_buffer32 { > __u32 offset; > compat_long_t userptr; > compat_caddr_t planes; > + __u32 fd; Ditto. > } m; > __u32 length; > __u32 reserved2; > @@ -348,6 +350,9 @@ static int get_v4l2_plane32(struct v4l2_plane *up, struct v4l2_plane32 *up32, > up_pln = compat_ptr(p); > if (put_user((unsigned long)up_pln, &up->m.userptr)) > return -EFAULT; > + } else if (memory == V4L2_MEMORY_DMABUF) { > + if (copy_in_user(&up->m.fd, &up32->m.fd, sizeof(int))) > + return -EFAULT; > } else { > if (copy_in_user(&up->m.mem_offset, &up32->m.mem_offset, > sizeof(__u32))) > @@ -371,6 +376,11 @@ static int put_v4l2_plane32(struct v4l2_plane *up, struct v4l2_plane32 *up32, > if (copy_in_user(&up32->m.mem_offset, &up->m.mem_offset, > sizeof(__u32))) > return -EFAULT; > + /* For DMABUF, driver might've set up the fd, so copy it back. */ > + if (memory == V4L2_MEMORY_DMABUF) > + if (copy_in_user(&up32->m.fd, &up->m.fd, > + sizeof(int))) > + return -EFAULT; > > return 0; > } > @@ -453,6 +463,10 @@ static int get_v4l2_buffer32(struct v4l2_buffer *kp, struct v4l2_buffer32 __user > if (get_user(kp->m.offset, &up->m.offset)) > return -EFAULT; > break; > + case V4L2_MEMORY_DMABUF: > + if (get_user(kp->m.fd, &up->m.fd)) > + return -EFAULT; > + break; > } > } > > @@ -517,6 +531,10 @@ static int put_v4l2_buffer32(struct v4l2_buffer *kp, struct v4l2_buffer32 __user > if (put_user(kp->m.offset, &up->m.offset)) > return -EFAULT; > break; > + case V4L2_MEMORY_DMABUF: > + if (put_user(kp->m.fd, &up->m.fd)) > + return -EFAULT; > + break; > } > } > > diff --git a/drivers/media/video/v4l2-ioctl.c b/drivers/media/video/v4l2-ioctl.c > index 6bc47fc..dffd3c9 100644 > --- a/drivers/media/video/v4l2-ioctl.c > +++ b/drivers/media/video/v4l2-ioctl.c > @@ -155,6 +155,7 @@ static const char *v4l2_memory_names[] = { > [V4L2_MEMORY_MMAP] = "mmap", > [V4L2_MEMORY_USERPTR] = "userptr", > [V4L2_MEMORY_OVERLAY] = "overlay", > + [V4L2_MEMORY_DMABUF] = "dmabuf", > }; > > #define prt_names(a, arr) ((((a) >= 0) && ((a) < ARRAY_SIZE(arr))) ? \ > diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h > index 7a147c8..7f918dc 100644 > --- a/include/linux/videodev2.h > +++ b/include/linux/videodev2.h > @@ -186,6 +186,7 @@ enum v4l2_memory { > V4L2_MEMORY_MMAP = 1, > V4L2_MEMORY_USERPTR = 2, > V4L2_MEMORY_OVERLAY = 3, > + V4L2_MEMORY_DMABUF = 4, > }; > > /* see also http://vektor.theorem.ca/graphics/ycbcr/ */ > @@ -596,6 +597,8 @@ struct v4l2_requestbuffers { > * should be passed to mmap() called on the video node) > * @userptr: when memory is V4L2_MEMORY_USERPTR, a userspace pointer > * pointing to this plane > + * @fd: when memory is V4L2_MEMORY_DMABUF, a userspace file > + * descriptor associated with this plane > * @data_offset: offset in the plane to the start of data; usually 0, > * unless there is a header in front of the data > * > @@ -610,6 +613,7 @@ struct v4l2_plane { > union { > __u32 mem_offset; > unsigned long userptr; > + int fd; > } m; > __u32 data_offset; > __u32 reserved[11]; > @@ -634,6 +638,8 @@ struct v4l2_plane { > * (or a "cookie" that should be passed to mmap() as offset) > * @userptr: for non-multiplanar buffers with memory == V4L2_MEMORY_USERPTR; > * a userspace pointer pointing to this buffer > + * @fd: for non-multiplanar buffers with memory == V4L2_MEMORY_DMABUF; > + * a userspace file descriptor associated with this buffer > * @planes: for multiplanar buffers; userspace pointer to the array of plane > * info structs for this buffer > * @length: size in bytes of the buffer (NOT its payload) for single-plane > @@ -660,6 +666,7 @@ struct v4l2_buffer { > __u32 offset; > unsigned long userptr; > struct v4l2_plane *planes; > + int fd; > } m; > __u32 length; > __u32 reserved2; > Regards, Hans
Hi Hans, Thank your for the review. Please refer to the comments below. On 08/22/2012 12:27 PM, Hans Verkuil wrote: > On Tue August 14 2012 17:34:31 Tomasz Stanislawski wrote: >> From: Sumit Semwal <sumit.semwal@ti.com> >> >> Adds DMABUF memory type to v4l framework. Also adds the related file >> descriptor in v4l2_plane and v4l2_buffer. >> >> Signed-off-by: Tomasz Stanislawski <t.stanislaws@samsung.com> >> [original work in the PoC for buffer sharing] >> Signed-off-by: Sumit Semwal <sumit.semwal@ti.com> >> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org> >> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> >> --- >> drivers/media/video/v4l2-compat-ioctl32.c | 18 ++++++++++++++++++ >> drivers/media/video/v4l2-ioctl.c | 1 + >> include/linux/videodev2.h | 7 +++++++ >> 3 files changed, 26 insertions(+) >> >> diff --git a/drivers/media/video/v4l2-compat-ioctl32.c b/drivers/media/video/v4l2-compat-ioctl32.c >> index 9ebd5c5..a2e0549 100644 >> --- a/drivers/media/video/v4l2-compat-ioctl32.c >> +++ b/drivers/media/video/v4l2-compat-ioctl32.c >> @@ -304,6 +304,7 @@ struct v4l2_plane32 { >> union { >> __u32 mem_offset; >> compat_long_t userptr; >> + __u32 fd; > > Shouldn't this be int? > Notice that this field should be consistent with fd field used in 'struct v4l2_exportbuffer'. Therefore I prefer to use fixed-size types. One could use __s32 here but notice that file descriptors are defined as small, nonnegative integers according to POSIX spec. The type __u32 suits well for this purpose. The negative values returned by open syscall are used only to indicate failures. On the other hand, using __s32 may help to avoid compiler warning while building userspace apps due to 'signed-vs-unsigned comparisons'. However, I do not have any strong opinion about 'int vs __u32' issue :). Do you think that using __s32 for both QUERYBUF and EXPBUF is a good compromise? >> } m; >> __u32 data_offset; >> __u32 reserved[11]; >> @@ -325,6 +326,7 @@ struct v4l2_buffer32 { >> __u32 offset; >> compat_long_t userptr; >> compat_caddr_t planes; >> + __u32 fd; > > Ditto. > >> } m; >> __u32 length; >> __u32 reserved2; > Regards, > > Hans > Regards, Tomasz
On Wed August 22 2012 14:09:18 Tomasz Stanislawski wrote: > Hi Hans, > Thank your for the review. > Please refer to the comments below. > > On 08/22/2012 12:27 PM, Hans Verkuil wrote: > > On Tue August 14 2012 17:34:31 Tomasz Stanislawski wrote: > >> From: Sumit Semwal <sumit.semwal@ti.com> > >> > >> Adds DMABUF memory type to v4l framework. Also adds the related file > >> descriptor in v4l2_plane and v4l2_buffer. > >> > >> Signed-off-by: Tomasz Stanislawski <t.stanislaws@samsung.com> > >> [original work in the PoC for buffer sharing] > >> Signed-off-by: Sumit Semwal <sumit.semwal@ti.com> > >> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org> > >> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > >> --- > >> drivers/media/video/v4l2-compat-ioctl32.c | 18 ++++++++++++++++++ > >> drivers/media/video/v4l2-ioctl.c | 1 + > >> include/linux/videodev2.h | 7 +++++++ > >> 3 files changed, 26 insertions(+) > >> > >> diff --git a/drivers/media/video/v4l2-compat-ioctl32.c b/drivers/media/video/v4l2-compat-ioctl32.c > >> index 9ebd5c5..a2e0549 100644 > >> --- a/drivers/media/video/v4l2-compat-ioctl32.c > >> +++ b/drivers/media/video/v4l2-compat-ioctl32.c > >> @@ -304,6 +304,7 @@ struct v4l2_plane32 { > >> union { > >> __u32 mem_offset; > >> compat_long_t userptr; > >> + __u32 fd; > > > > Shouldn't this be int? > > > > Notice that this field should be consistent with fd field used in > 'struct v4l2_exportbuffer'. Therefore I prefer to use fixed-size types. > One could use __s32 here but notice that file descriptors are defined > as small, nonnegative integers according to POSIX spec. The type __u32 > suits well for this purpose. The negative values returned by open > syscall are used only to indicate failures. > > On the other hand, using __s32 may help to avoid compiler warning while > building userspace apps due to 'signed-vs-unsigned comparisons'. > > However, I do not have any strong opinion about 'int vs __u32' issue :). > Do you think that using __s32 for both QUERYBUF and EXPBUF is a good > compromise? The type of a fd is highly variable in the kernel. Just try this for fun: grep [^a-z]fd[^a-z] -rsI include/linux/ 'int' or 'unsigned int' are by far the most common types. But in structs I did see a few __s32 types, so I think __s32 is a decent type to use. Just make sure it is __s32 everywhere. Right now __u32 and int are both used. Regards, Hans > > >> } m; > >> __u32 data_offset; > >> __u32 reserved[11]; > >> @@ -325,6 +326,7 @@ struct v4l2_buffer32 { > >> __u32 offset; > >> compat_long_t userptr; > >> compat_caddr_t planes; > >> + __u32 fd; > > > > Ditto. > > > >> } m; > >> __u32 length; > >> __u32 reserved2; > > > Regards, > > > > Hans > > > > Regards, > > Tomasz > -- > To unsubscribe from this list: send the line "unsubscribe linux-media" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >
diff --git a/drivers/media/video/v4l2-compat-ioctl32.c b/drivers/media/video/v4l2-compat-ioctl32.c index 9ebd5c5..a2e0549 100644 --- a/drivers/media/video/v4l2-compat-ioctl32.c +++ b/drivers/media/video/v4l2-compat-ioctl32.c @@ -304,6 +304,7 @@ struct v4l2_plane32 { union { __u32 mem_offset; compat_long_t userptr; + __u32 fd; } m; __u32 data_offset; __u32 reserved[11]; @@ -325,6 +326,7 @@ struct v4l2_buffer32 { __u32 offset; compat_long_t userptr; compat_caddr_t planes; + __u32 fd; } m; __u32 length; __u32 reserved2; @@ -348,6 +350,9 @@ static int get_v4l2_plane32(struct v4l2_plane *up, struct v4l2_plane32 *up32, up_pln = compat_ptr(p); if (put_user((unsigned long)up_pln, &up->m.userptr)) return -EFAULT; + } else if (memory == V4L2_MEMORY_DMABUF) { + if (copy_in_user(&up->m.fd, &up32->m.fd, sizeof(int))) + return -EFAULT; } else { if (copy_in_user(&up->m.mem_offset, &up32->m.mem_offset, sizeof(__u32))) @@ -371,6 +376,11 @@ static int put_v4l2_plane32(struct v4l2_plane *up, struct v4l2_plane32 *up32, if (copy_in_user(&up32->m.mem_offset, &up->m.mem_offset, sizeof(__u32))) return -EFAULT; + /* For DMABUF, driver might've set up the fd, so copy it back. */ + if (memory == V4L2_MEMORY_DMABUF) + if (copy_in_user(&up32->m.fd, &up->m.fd, + sizeof(int))) + return -EFAULT; return 0; } @@ -453,6 +463,10 @@ static int get_v4l2_buffer32(struct v4l2_buffer *kp, struct v4l2_buffer32 __user if (get_user(kp->m.offset, &up->m.offset)) return -EFAULT; break; + case V4L2_MEMORY_DMABUF: + if (get_user(kp->m.fd, &up->m.fd)) + return -EFAULT; + break; } } @@ -517,6 +531,10 @@ static int put_v4l2_buffer32(struct v4l2_buffer *kp, struct v4l2_buffer32 __user if (put_user(kp->m.offset, &up->m.offset)) return -EFAULT; break; + case V4L2_MEMORY_DMABUF: + if (put_user(kp->m.fd, &up->m.fd)) + return -EFAULT; + break; } } diff --git a/drivers/media/video/v4l2-ioctl.c b/drivers/media/video/v4l2-ioctl.c index 6bc47fc..dffd3c9 100644 --- a/drivers/media/video/v4l2-ioctl.c +++ b/drivers/media/video/v4l2-ioctl.c @@ -155,6 +155,7 @@ static const char *v4l2_memory_names[] = { [V4L2_MEMORY_MMAP] = "mmap", [V4L2_MEMORY_USERPTR] = "userptr", [V4L2_MEMORY_OVERLAY] = "overlay", + [V4L2_MEMORY_DMABUF] = "dmabuf", }; #define prt_names(a, arr) ((((a) >= 0) && ((a) < ARRAY_SIZE(arr))) ? \ diff --git a/include/linux/videodev2.h b/include/linux/videodev2.h index 7a147c8..7f918dc 100644 --- a/include/linux/videodev2.h +++ b/include/linux/videodev2.h @@ -186,6 +186,7 @@ enum v4l2_memory { V4L2_MEMORY_MMAP = 1, V4L2_MEMORY_USERPTR = 2, V4L2_MEMORY_OVERLAY = 3, + V4L2_MEMORY_DMABUF = 4, }; /* see also http://vektor.theorem.ca/graphics/ycbcr/ */ @@ -596,6 +597,8 @@ struct v4l2_requestbuffers { * should be passed to mmap() called on the video node) * @userptr: when memory is V4L2_MEMORY_USERPTR, a userspace pointer * pointing to this plane + * @fd: when memory is V4L2_MEMORY_DMABUF, a userspace file + * descriptor associated with this plane * @data_offset: offset in the plane to the start of data; usually 0, * unless there is a header in front of the data * @@ -610,6 +613,7 @@ struct v4l2_plane { union { __u32 mem_offset; unsigned long userptr; + int fd; } m; __u32 data_offset; __u32 reserved[11]; @@ -634,6 +638,8 @@ struct v4l2_plane { * (or a "cookie" that should be passed to mmap() as offset) * @userptr: for non-multiplanar buffers with memory == V4L2_MEMORY_USERPTR; * a userspace pointer pointing to this buffer + * @fd: for non-multiplanar buffers with memory == V4L2_MEMORY_DMABUF; + * a userspace file descriptor associated with this buffer * @planes: for multiplanar buffers; userspace pointer to the array of plane * info structs for this buffer * @length: size in bytes of the buffer (NOT its payload) for single-plane @@ -660,6 +666,7 @@ struct v4l2_buffer { __u32 offset; unsigned long userptr; struct v4l2_plane *planes; + int fd; } m; __u32 length; __u32 reserved2;