From 0a08088f82c2db9cd6bce3258c79a76980c77651 Mon Sep 17 00:00:00 2001 From: Dillon Min Date: Tue, 19 Oct 2021 09:43:18 +0100 Subject: [PATCH] media: v4l2-mem2mem: add v4l2_m2m_get_unmapped_area for no-mmu platform For platforms without MMU the m2m provides a helper method v4l2_m2m_get_unmapped_area(), The mmap() routines will call this to get a proposed address for the mapping. More detailed information about get_unmapped_area can be found in Documentation/nommu-mmap.txt Signed-off-by: Dillon Min Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/v4l2-core/v4l2-mem2mem.c | 21 +++++++++++++++++++++ include/media/v4l2-mem2mem.h | 5 +++++ 2 files changed, 26 insertions(+) diff --git a/drivers/media/v4l2-core/v4l2-mem2mem.c b/drivers/media/v4l2-core/v4l2-mem2mem.c index e7f4bf5bc8dd..e2654b422334 100644 --- a/drivers/media/v4l2-core/v4l2-mem2mem.c +++ b/drivers/media/v4l2-core/v4l2-mem2mem.c @@ -966,6 +966,27 @@ int v4l2_m2m_mmap(struct file *file, struct v4l2_m2m_ctx *m2m_ctx, } EXPORT_SYMBOL(v4l2_m2m_mmap); +#ifndef CONFIG_MMU +unsigned long v4l2_m2m_get_unmapped_area(struct file *file, unsigned long addr, + unsigned long len, unsigned long pgoff, + unsigned long flags) +{ + struct v4l2_fh *fh = file->private_data; + unsigned long offset = pgoff << PAGE_SHIFT; + struct vb2_queue *vq; + + if (offset < DST_QUEUE_OFF_BASE) { + vq = v4l2_m2m_get_src_vq(fh->m2m_ctx); + } else { + vq = v4l2_m2m_get_dst_vq(fh->m2m_ctx); + pgoff -= (DST_QUEUE_OFF_BASE >> PAGE_SHIFT); + } + + return vb2_get_unmapped_area(vq, addr, len, pgoff, flags); +} +EXPORT_SYMBOL_GPL(v4l2_m2m_get_unmapped_area); +#endif + #if defined(CONFIG_MEDIA_CONTROLLER) void v4l2_m2m_unregister_media_controller(struct v4l2_m2m_dev *m2m_dev) { diff --git a/include/media/v4l2-mem2mem.h b/include/media/v4l2-mem2mem.h index 5a91b548ecc0..fdbd5257e020 100644 --- a/include/media/v4l2-mem2mem.h +++ b/include/media/v4l2-mem2mem.h @@ -495,6 +495,11 @@ __poll_t v4l2_m2m_poll(struct file *file, struct v4l2_m2m_ctx *m2m_ctx, int v4l2_m2m_mmap(struct file *file, struct v4l2_m2m_ctx *m2m_ctx, struct vm_area_struct *vma); +#ifndef CONFIG_MMU +unsigned long v4l2_m2m_get_unmapped_area(struct file *file, unsigned long addr, + unsigned long len, unsigned long pgoff, + unsigned long flags); +#endif /** * v4l2_m2m_init() - initialize per-driver m2m data * -- 2.11.0