snd_pcm_lib_default_mmap(9)

💅 snd_pcm_lib_default_mmap(9) — the Kernel API Manual cutie era

okay so bestie, we're in the Kernel API Manual today and this page is literally about snd_pcm_lib_default_mmap and it's lowkey iconic?? no cap, it's the little default handler that could 💖

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✨ NAME ✨

snd_pcm_lib_default_mmap — Default PCM data mmap function 🎀

like, the mmap function that ships as the default for PCM data. that's the whole vibe.

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🦋 SYNOPSIS 🦋

int snd_pcm_lib_default_mmap (struct snd_pcm_substream *substream ,
struct vm_area_struct *area );

she takes two args and returns an int, periodt ✨

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🌸 ARGUMENTS 🌸

• substream — the PCM substream 🎧 (yes bestie, the substream, the main character)
• area — the VMA 💫

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🔥 DESCRIPTION 🔥

so here's the tea ☕ — this is the default mmap handler for PCM data.

and the way that it gets called is actually so sneaky: when mmap pcm_ops is NULL, this function is invoked implicitly. like, nobody calls her by name, she just shows up 💅 iykyk

fr fr remember: implicit invocation only happens when that mmap pcm_ops is NULL. don't come for me if you set it and she ghosts you 🙈

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⭐ RETURN ⭐

• zero if successful 🎉
• or a negative error code 😭 (the classic)

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👑 SEE ALSO 👑

okay this list is giving extended universe, we got the Kernel file first:

./sound/core/pcm_native.c

and then the whole friend group 🫶:

• snd_pcm_stream_lock(9)
• snd_pcm_stream_unlock(9)
• snd_pcm_stream_lock_irq(9)
• snd_pcm_stream_unlock_irq(9)
• snd_pcm_stream_unlock_irqrestore(9)
• snd_pcm_set_state(9)
• snd_pcm_get_state(9)
• snd_pcm_hw_params_choose(9)
• snd_pcm_start(9)
• snd_pcm_stop(9)
• snd_pcm_drain_done(9)
• snd_pcm_stop_xrun(9)
• snd_pcm_suspend_all(9)
• snd_pcm_prepare(9)
• snd_pcm_kernel_ioctl(9)
• snd_pcm_lib_mmap_iomem(9)

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🌈 the sign-off 🌈

and that's the whole page bestie!! this lil' beauty lives in ./sound/core, it's tagged October 2026, it's page snd_pcm_lib_default_mmap(9) out of the Kernel API Manual, and honestly?? she ate 💅✨ go mmap something, ily 🫶💖