vb2_get_unmapped_area(9)

🌸 NAME 🌸

okay bestie, meet vb2_get_unmapped_area(9) from the Kernel API Manual — it maps video buffers into application address space. periodt. 💖

✨ SYNOPSIS ✨

the signature is giving exactly this:

unsigned long vb2_get_unmapped_area (struct vb2_queue *q , unsigned long
       addr , unsigned long len , unsigned long pgoff , unsigned long flags );

🫶 ARGUMENTS 🫶

• q — pointer to struct vb2_queue with videobuf2 queue.
• addr — memory address.
• len — buffer size.
• pgoff — page offset.
• flags — memory flags.

💅 DESCRIPTION 💅

so like, this function is used on noMMU platforms to propose address mapping for a given buffer. it’s intended to be used as a handler for the file_operations->get_unmapped_area operation — lowkey iconic handler behavior. ✨

when !CONFIG_MMU, the mmap syscall routines will call this to get a proposed address for the mapping. that’s the whole vibe check. 🦋

🦋 SEE ALSO 🦋

Kernel file ./include/media/videobuf2-core.h is the main-character icon here, and the whole friend group is: enum vb2_memory(9), struct vb2_mem_ops(9), struct vb2_plane(9), enum vb2_io_modes(9), enum vb2_buffer_state(9), struct vb2_buffer(9), struct vb2_ops(9), struct vb2_buf_ops(9), struct vb2_queue(9), vb2_queue_allows_cache_hints(9), vb2_plane_vaddr(9), vb2_plane_cookie(9), vb2_buffer_done(9), vb2_discard_done(9), vb2_wait_for_all_buffers(9), vb2_core_querybuf(9), vb2_core_reqbufs(9), vb2_core_create_bufs(9), vb2_core_prepare_buf(9), vb2_core_remove_bufs(9), vb2_core_qbuf(9), vb2_core_dqbuf(9), vb2_core_streamon(9), vb2_core_streamoff(9), vb2_core_expbuf(9), vb2_core_queue_init(9), vb2_core_queue_release(9), vb2_queue_error(9), vb2_mmap(9), vb2_core_poll(9), vb2_read(9), vb2_write(9), vb2_thread_fnc(9), vb2_thread_start(9), vb2_thread_stop(9), vb2_is_streaming(9), vb2_fileio_is_active(9), vb2_get_num_buffers(9), vb2_is_busy(9), vb2_get_drv_priv(9), vb2_set_plane_payload(9), vb2_get_plane_payload(9), vb2_plane_size(9), vb2_start_streaming_called(9), vb2_clear_last_buffer_dequeued(9), vb2_get_buffer(9), vb2_buffer_in_use(9), vb2_verify_memory_type(9), vb2_request_object_is_buffer(9), vb2_request_buffer_cnt(9).

xoxo, your kernel bestie 💖 — source/version vibes: ./include/media and October 2026, Kernel API Manual era. 🎀