msgdma_prep_memcpy(9)

✨ NAME ✨

okay so bestie, we're looking at msgdma_prep_memcpy(9) from the Kernel API Manual, and she is literally here for descriptor prep for a memcpy transaction. Periodt.

• msgdma_prep_memcpy — prepare descriptors for memcpy transaction

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🦋 SYNOPSIS 🦋

the way this signature ate, no cap:

struct dma_async_tx_descriptor * msgdma_prep_memcpy (struct dma_chan
       *dchan , dma_addr_t dma_dst , dma_addr_t dma_src , size_t len , ulong
       flags );

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💅 ARGUMENTS 💅

these are the little besties she needs to do her thing:

• dchan — DMA channel
• dma_dst — Destination buffer address
• dma_src — Source buffer address
• len — Transfer length
• flags — transfer ack flags

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🎀 RETURN 🎀

Async transaction descriptor on success and NULL on failure.

so yeah: success gives you the async transaction descriptor, and failure gives you NULL — not me crying over a NULL return 😭💀

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🔥 SEE ALSO 🔥

go touch grass in these files and functions, iykyk:

• Kernel file ./drivers/dma/altera-msgdma.c
• struct msgdma_extended_desc(9)
• struct msgdma_sw_desc(9)
• msgdma_get_descriptor(9)
• msgdma_free_descriptor(9)
• msgdma_free_desc_list(9)
• msgdma_desc_config(9)
• msgdma_desc_config_eod(9)
• msgdma_tx_submit(9)
• msgdma_prep_slave_sg(9)
• msgdma_copy_desc_to_fifo(9)
• msgdma_start_transfer(9)
• msgdma_issue_pending(9)
• msgdma_chan_desc_cleanup(9)
• msgdma_complete_descriptor(9)
• msgdma_free_descriptors(9)
• msgdma_free_chan_resources(9)
• msgdma_alloc_chan_resources(9)
• msgdma_tasklet(9)
• msgdma_irq_handler(9)
• msgdma_dev_remove(9)
• msgdma_probe(9)
• msgdma_remove(9)

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cute sign-off bestie: source/version ./drivers/dma, date October 2026, manual page msgdma_prep_memcpy(9) — all accounted for, slay 💖🫶✨