afu_dma_region_find(9)

🌸 NAME 🌸

okay bestie, welcome to afu_dma_region_find(9) — yes, that's the title, and this page lives in the Kernel API Manual ✨

afu_dma_region_find — find the dma region from rbtree based on iova and size 💖

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🦋 SYNOPSIS 🦋

struct dfl_afu_dma_region * afu_dma_region_find (struct dfl_feature_dev_data *fdata , u64 iova , u64 size );

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🎀 ARGUMENTS 🎀

• fdata — feature dev data 🫶
• iova — address of the dma memory area 🌈
• size — size of the dma memory area 🎀

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✨ DESCRIPTION ✨

okay so bestie, it finds the dma region from the rbtree based on iova and size — like a little kernel treasure hunt, but make it DMA 💅

• if size == 0, it finds the dma region which starts from iova 🌸
• otherwise, it finds the dma region which fully contains [iova, iova+size) 🔥

If nothing is matched returns NULL — like, no match, no vibes 😭

⚠️ Needs to be called with fdata->lock held. no cap, hold that lock before you call this 🔒

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💜 SEE ALSO 💜

• Kernel file ./drivers/fpga/dfl-afu-dma-region.c
• afu_dma_pin_pages(9)
• afu_dma_unpin_pages(9)
• afu_dma_check_continuous_pages(9)
• dma_region_check_iova(9)
• afu_dma_region_add(9)
• afu_dma_region_remove(9)
• afu_dma_region_destroy(9)
• afu_dma_region_find_iova(9)
• afu_dma_map_region(9)
• afu_dma_unmap_region(9)

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mwah 💋 this cutie page's source/version is ./drivers/fpga, dated October 2026 — periodt 🎀✨