virtsnd_pcm_msg_alloc(9)

💖 NAME 💖

okay so welcome to the Kernel API Manual bestie, this is virtsnd_pcm_msg_alloc — and it's literally the glow-up moment where we allocate I/O messages. that's the whole vibe. 🎀

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✨ SYNOPSIS ✨

int virtsnd_pcm_msg_alloc (struct virtio_pcm_substream *vss , unsigned
int periods , unsigned int period_bytes );

like yes she's a little long but she's iconic, don't come for her 💅

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🌸 ARGUMENTS 🌸

• vss — the VirtIO PCM substream in question. the main character, honestly 🫶
• periods — the current number of periods. yes, current. keep up ✨
• period_bytes — the current period size, measured in bytes. numbers bestie, we love her 🍓

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🦋 DESCRIPTION 🦋

so here's the tea: this function takes your buffer and slices it into periods parts — each one exactly period_bytes in size — and then it creates periods corresponding I/O messages. like cutting a cake into perfectly equal pieces and then handing each piece its own little message. ate. no crumbs. 🎂✨

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🧚 CONTEXT 🧚

any context that permits to sleep 😴 — so don't be out here calling this from somewhere spicy, okay? she needs her nap time.

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⭐ RETURN ⭐

• 0 — success, we slayed 💅
• -ENOMEM — failure, out of memory, not the vibe 😭

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🔥 SEE ALSO 🔥

kernel file ./sound/virtio/virtio_pcm_msg.c — go read her, she's right there 👑

plus the whole friend group:

• struct virtio_pcm_msg(9)
• enum pcm_msg_sg_index(9)
• virtsnd_pcm_sg_num(9)
• virtsnd_pcm_sg_from(9)
• virtsnd_pcm_msg_free(9)
• virtsnd_pcm_msg_send(9)
• virtsnd_pcm_msg_pending_num(9)
• virtsnd_pcm_msg_complete(9)
• virtsnd_pcm_notify_cb(9)
• virtsnd_pcm_tx_notify_cb(9)
• virtsnd_pcm_rx_notify_cb(9)
• virtsnd_pcm_ctl_msg_alloc(9)

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and that's the whole page bestie, mwah 💖

so like, this little icon lives in ./sound/virtio, it's dated October 2026, and you can find her filed under virtsnd_pcm_msg_alloc(9). periodt. 🌈👑