STRUCT DRM_GEM_SHMEM_OBJECT(9)

💖 NAME 💖

okay bestie, this is struct drm_gem_shmem_object from the Kernel API Manual — and it is literally the GEM object backed by shmem. no cap, that's the whole name. 🫶

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✨ SYNOPSIS ✨

       struct drm_gem_shmem_object {
           struct drm_gem_object base;
           struct page **pages;
           refcount_t pages_use_count;
           refcount_t pages_pin_count;
           int madv;
           struct list_head madv_list;
           struct sg_table *sgt;
           void *vaddr;
           refcount_t vmap_use_count;
           bool pages_mark_dirty_on_put : 1;
           bool pages_mark_accessed_on_put : 1;
           bool map_wc : 1;
        };

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🎀 Members 🎀

here's the member-by-member vibe check, bestie 👑

• base — Base GEM object 💅
• pages — Page table 📄
• pages_use_count — Reference count on the pages table. The pages are put when the count reaches zero. ✨
• pages_pin_count — Reference count on the pinned pages table.

Pages are hard-pinned and reside in memory if count greater than zero. Otherwise, when count is zero, the pages are allowed to be evicted and purged by memory shrinker. 😭

• madv — State for madvise.

0 is active/inuse. A negative value is the object is purged. Positive values are driver specific and not used by the helpers. 🌀

• madv_list — List entry for madvise tracking.

Typically used by drivers to track purgeable objects 🧚

• sgt — Scatter/gather table for imported PRIME buffers 🦋
• vaddr — Kernel virtual address of the backing memory 🌸
• vmap_use_count — Reference count on the virtual address. The address is unmapped when the count reaches zero. ⭐
• pages_mark_dirty_on_put — Mark pages as dirty when they are put. 🎀
• pages_mark_accessed_on_put — Mark pages as accessed when they are put. 🎀
• map_wc — map object write-combined (instead of using shmem defaults). 🔥

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🌈 SEE ALSO 🌈

• Kernel file ./include/drm/drm_gem_shmem_helper.h
• drm_gem_shmem_object_free(9)
• drm_gem_shmem_object_print_info(9)
• drm_gem_shmem_object_pin(9)
• drm_gem_shmem_object_unpin(9)
• drm_gem_shmem_object_get_sg_table(9)
• drm_gem_shmem_object_mmap(9)
• DRM_GEM_SHMEM_DRIVER_OPS(9)

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okay that's the whole page, mwah 💋 — source/version ./include/drm, date October 2026, and the title is struct drm_gem_shmem_object(9). bye bestie, slay your shmem 🫶✨