iosys_map_wr(9)

✨ iosys_map_wr(9) ✨

okay bestie, welcome to the Kernel API Manual 💖 this one is a lil function called iosys_map_wr and it's literally the "write a C-type value to the iosys_map" queen 👑

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🌸 NAME 🌸

iosys_map_wr — Write a C-type value to the iosys_map 🫶

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🎀 SYNOPSIS 🎀

iosys_map_wr (map__ , offset__ , type__ , val__ );

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🦋 ARGUMENTS 🦋

• map__ — The iosys_map structure 💅 like, the map itself, the whole vibe
• offset__ — The offset from the mapping to write to 📍 where in the map we're dropping the value
• type__ — Type of the value being written 🏷️ so it knows what it's dealing with
• val__ — Value to write ✍️ the actual thing going in

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⭐ DESCRIPTION ⭐

So here's the tea ☕: this writes a C type value — specifically u8, u16, u32 and u64 — to the iosys_map. Slay, simple, iconic. 👑

but like… for other types, or if the pointer may be unaligned (which is lowkey problematic for the architecture supported 😭), you gotta use iosys_map_memcpy_to instead. no cap, don't skip that part.

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🌈 SEE ALSO 🌈

the whole friend group fr fr 🫶 — starting with the Kernel file ./include/linux/iosys-map.h overview(9):

• overview(9)
• struct iosys_map(9)
• IOSYS_MAP_INIT_VADDR(9)
• IOSYS_MAP_INIT_VADDR_IOMEM(9)
• IOSYS_MAP_INIT_OFFSET(9)
• iosys_map_set_vaddr(9)
• iosys_map_set_vaddr_iomem(9)
• iosys_map_is_equal(9)
• iosys_map_is_null(9)
• iosys_map_is_set(9)
• iosys_map_clear(9)
• iosys_map_memcpy_to(9)
• iosys_map_memcpy_from(9)
• iosys_map_incr(9)
• iosys_map_memset(9)
• iosys_map_rd(9)
• iosys_map_rd_field(9)
• iosys_map_wr_field(9)

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and that's the whole page bestie, mwah 💋 this little icon lives in ./include/linux, stamped October 2026 — go forth and write those u8s, u16s, u32s and u64s 🍓🧚💜