STRUCT PANTHOR_GEM_OBJECT(9)

💖 NAME 💖

struct panthor_gem_object — the driver-specific GEM object, bestie. Like, this is the Panthor driver's very own GEM object struct, no cap ✨

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🌸 SYNOPSIS 🌸

struct panthor_gem_object {
    struct drm_gem_object base;
    struct panthor_gem_backing backing;
    struct panthor_gem_cpu_map cmap;
    struct panthor_gem_dev_map dmap;
    enum panthor_gem_reclaim_state reclaim_state;
    atomic_t reclaimed_count;
    struct drm_gem_object *exclusive_vm_root_gem;
    u32 flags;
    struct {
      const char *str;
      struct mutex lock;
    } label;
  #ifdef CONFIG_DEBUG_FS;
    struct panthor_gem_debugfs debugfs;
  #endif;
  };

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👑 MEMBERS 👑

Ok so let's go field by field, because every single one of these is carrying the whole team on its back 🫶

• base — inherits from drm_gem_object. It's giving "my parent is iconic and I'm their main character child" 💅
• backing — the memory backing state. The literal foundation, lowkey.
• cmap — CPU mapping state.
• dmap — device mapping state.
• reclaim_state — the cached reclaim state.
• reclaimed_count — how many times the object has been evicted to swap 😭 The count saturates at INT_MAX and will never wrap around to 0. Periodt — it hits the ceiling and stays there, it does not loop back around, fr fr.
• exclusive_vm_root_gem — the root GEM of the exclusive VM that this GEM object is attached to.

So listen: if exclusive_vm_root_gem != NULL, then any attempt to bind the GEM to a different VM will fail. That's the vibe check and it does not negotiate 💀

Also, all FW memory objects have this field set to the root GEM of the MCU VM. Noted, queen.

• flags — a combination of drm_panthor_bo_flags flags.
• label — the BO tagging fields 🎀 The label can be assigned within the driver itself or through a specific IOCTL.
• label.str — pointer to NULL-terminated string,

🧚 tiny note: the struct also has a struct mutex lock; hanging out inside label, and a struct panthor_gem_debugfs debugfs; that only exists #ifdef CONFIG_DEBUG_FS — both fully in the synopsis above, so nobody's getting left out 🙈

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🦋 SEE ALSO 🦋

Kernel file ./drivers/gpu/drm/panthor/panthor_gem.h, plus these absolute icons:

• struct panthor_gem_debugfs(9)
• struct panthor_gem_backing(9)
• struct panthor_gem_cpu_map(9)
• struct panthor_gem_dev_map(9)
• enum panthor_gem_reclaim_state(9)
• struct panthor_kernel_bo(9)

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💜 and that's the whole page, bestie 💜 This little beauty lives over at ./drivers/gpu/drm/panthor, and this version is dated October 2026. Go forth and bind responsibly 😭✨🎀