cache_seg_is_ctrl_seg(9)

💅 cache_seg_is_ctrl_seg(9) — NAME ✨

okay so bestie, this page is straight out of the Kernel API Manual, and it's all about cache_seg_is_ctrl_seg — literally the function that checks if a cache segment is a cache ctrl segment. that's it, that's the whole vibe. 🎀

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🦋 SYNOPSIS 🦋

bool cache_seg_is_ctrl_seg (u32 cache_seg_id );

no cap, that's the exact signature — keep it cute, keep it bool. ✨

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🌸 ARGUMENTS 🌸

• cache_seg_id — the ID of the cache segment. that's the one thing you pass in, bestie. 💖

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👑 DESCRIPTION 👑

so here's the tea: this function returns true if the cache segment ID corresponds to a cache ctrl segment. literally a vibe check for your segment ID — either it's giving cache ctrl, or it's not. 💅

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🔥 NOTE 🔥

real talk, this part matters: we extend the segment control of the first cache segment (cache segment ID 0) to serve as the cache control (pcache_cache_ctrl) for the entire PCACHE cache. iconic behavior, honestly.

this function determines whether the given cache segment is the one storing the pcache_cache_ctrl information. so yeah — it's checking for that segment specifically. 🫶

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🌈 SEE ALSO 🌈

• Kernel file ./drivers/md/dm-pcache/cache.h — the whole squad lives here, iykyk
• cache_seg_id_valid(9)
• cache_key_cutfront(9)
• cache_key_cutback(9)
• cache_key_data_crc(9)
• kset_onmedia_valid(9)
• cache_seg_remain(9)
• cache_key_invalid(9)
• cache_key_lstart(9)
• cache_key_lend(9)
• cache_pos_onmedia_crc(9)

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and that's the whole page, bestie — brought to you by ./drivers/md/dm-pcache, dated October 2026, serving cache_seg_is_ctrl_seg(9) realness. periodt. 💜🎀