i915_gem_gtt_reserve(9)

✨ i915_gem_gtt_reserve(9) ✨

okay so bestie, welcome to the Kernel API Manual page for i915_gem_gtt_reserve 💅 this is the one that literally reserves you a spot in the GTT, no cap 🎀

---

💖 NAME 💖

i915_gem_gtt_reserve — reserve a node in an address_space (GTT) 🦋

---

🌸 SYNOPSIS 🌸

int i915_gem_gtt_reserve (struct i915_address_space *vm , struct
i915_gem_ww_ctx *ww , struct drm_mm_node *node , u64 size , u64 offset ,
unsigned long color , unsigned int flags );

like, that's the whole signature, slay ✨

---

🎀 ARGUMENTS 🎀

• vm — the struct i915_address_space 👑 that's your address space, the whole vibe zone
• ww — an optional struct i915_gem_ww_ctx. optional!! she can be NULL, it's fine 🙈
• node — the struct drm_mm_node (typically i915_vma.node) — the actual lil node you're placing 🍓
• size — how much space to allocate inside the GTT, and it must be #I915_GTT_PAGE_SIZE aligned ⭐ don't forget, alignment is not optional here
• offset — where to insert inside the GTT. must be #I915_GTT_MIN_ALIGNMENT aligned, and the node (offset + size) must fit within the address space 📏 like do the math first bestie, it has to fit
• color — color to apply to node. ok and this is important: if this node is not from a VMA, color must be #I915_COLOR_UNEVICTABLE 🔥 no exceptions
• flags — control search and eviction behaviour 🧚

---

💜 DESCRIPTION 💜

so i915_gem_gtt_reserve tries to insert the node at the exact offset inside the address space (using size and color) 🎯 like, precise placement, main character energy.

if the node does not fit, she tries to evict any overlapping nodes from the GTT — including any neighbouring nodes if the colors do not match (this is to ensure guard pages between differing domains, iykyk) 💀 see i915_gem_evict_for_node for the gory details on the eviction algorithm 👻

#PIN_NONBLOCK may be used to prevent waiting on evicting active overlapping objects 🫶

and heads up — any overlapping node that is pinned or marked as unevictable will also result in failure 😭 like she simply cannot move those, periodt.

---

🌈 RETURN 🌈

• 0 — on success 💖 yay
• -ENOSPC — if no suitable hole is found 🕳️😔
• -EINTR — if asked to wait for eviction and interrupted ✋

---

🦋 SEE ALSO 🦋

Kernel file ./drivers/gpu/drm/i915/i915_gem_gtt.c and i915_gem_gtt_insert(9) 🌟 go read those too, they're lowkey iconic

---

ok that's the whole page bestie, you're officially certified in GTT node reservation 💅✨

and finally, the cute sign-off: this whole thing lives over at ./drivers/gpu/drm/i915, it's from October 2026, and yeah — the manual name is i915_gem_gtt_reserve(9) in case you forgot already 🎀💜 see u at the next manpage 🫶