kfifo_dma_out_finish(9)

kfifo_dma_out_finish(9) — a Kernel API Manual moment 💅

okay so bestie, we are in the Kernel API Manual and this page is about a tiny but important macro. let's get into it 🫶

🌸 NAME 🌸

kfifo_dma_out_finish — finish a DMA OUT operation

✨ SYNOPSIS ✨

kfifo_dma_out_finish (fifo , len );

🎀 ARGUMENTS 🎀

• fifo — address of the fifo to be used
• len — number of bytes transferred

🦋 DESCRIPTION 🦋

okay so this macro finishes a DMA OUT operation. the out counter will be updated by the len parameter. and no error checking will be done — like, none, zero, it is not doing a vibe check on your errors 😭.

also the locking tea: note that with only one concurrent reader and one concurrent writer, you don't need extra locking to use these macros. periodt 💅

👑 SEE ALSO 👑

peep the Kernel file ./include/linux/kfifo.h and these iconic siblings:

• DECLARE_KFIFO_PTR(9)
• DECLARE_KFIFO(9)
• INIT_KFIFO(9)
• DEFINE_KFIFO(9)
• kfifo_initialized(9)
• kfifo_esize(9)
• kfifo_recsize(9)
• kfifo_size(9)
• kfifo_reset(9)
• kfifo_reset_out(9)
• kfifo_len(9)
• kfifo_is_empty(9)
• kfifo_is_empty_spinlocked(9)
• kfifo_is_empty_spinlocked_noirqsave(9)
• kfifo_is_full(9)
• kfifo_avail(9)
• kfifo_skip_count(9)
• kfifo_skip(9)
• kfifo_peek_len(9)
• kfifo_alloc(9)
• kfifo_alloc_node(9)
• kfifo_free(9)
• kfifo_init(9)
• kfifo_put(9)
• kfifo_get(9)
• kfifo_peek(9)
• kfifo_in(9)
• kfifo_in_spinlocked(9)
• kfifo_in_spinlocked_noirqsave(9)
• kfifo_out(9)
• kfifo_out_spinlocked(9)
• kfifo_out_spinlocked_noirqsave(9)
• kfifo_from_user(9)
• kfifo_to_user(9)
• kfifo_dma_in_prepare_mapped(9)
• kfifo_dma_in_finish(9)
• kfifo_dma_out_prepare_mapped(9)
• kfifo_out_peek(9)
• kfifo_out_linear(9)
• kfifo_out_linear_ptr(9)

signing off from the Kernel API Manual 💜 source/version: ./include/linux, date: October 2026, page: kfifo_dma_out_finish(9) — byeee 🫶✨