STRUCT UFS_HW_QUEUE(9)

💅 struct ufs_hw_queue(9) — Kernel API Manual 🦋

okay so bestie, welcome to the struct ufs_hw_queue page, aka the per hardware queue structure era. this is from the Kernel API Manual and honestly? it's giving "one queue to rule them all" energy 👑

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✨ NAME ✨

struct ufs_hw_queue — literally the per hardware queue structure. that's it. that's the vibe. one struct, one hardware queue, no cap 💖

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🌸 SYNOPSIS 🌸

like, here's the whole shape of her, exactly as she is:

struct ufs_hw_queue {
    void __iomem *mcq_sq_head;
    void __iomem *mcq_sq_tail;
    void __iomem *mcq_cq_head;
    void __iomem *mcq_cq_tail;
    struct utp_transfer_req_desc *sqe_base_addr;
    dma_addr_t sqe_dma_addr;
    struct cq_entry *cqe_base_addr;
    dma_addr_t cqe_dma_addr;
    u32 max_entries;
    u32 id;
    u32 sq_tail_slot;
    spinlock_t sq_lock;
    u32 cq_tail_slot;
    u32 cq_head_slot;
    spinlock_t cq_lock;
    struct mutex sq_mutex;
 };

no notes, she's perfect 🎀

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🫶 Members 🫶

okay so here's the member-by-member breakdown, iykyk:

• mcq_sq_head — base address of the submission queue head pointer. the head. the beginning. main character energy ⭐
• mcq_sq_tail — base address of the submission queue tail pointer. the tail knows where it's at 💅
• mcq_cq_head — base address of the completion queue head pointer 🙈
• mcq_cq_tail — base address of the completion queue tail pointer 🦋
• sqe_base_addr — submission queue entry base address. the actual entries live here fr fr
• sqe_dma_addr — submission queue dma address 🔥
• cqe_base_addr — completion queue base address 💖
• cqe_dma_addr — completion queue dma address ✨
• max_entries — max number of slots in this hardware queue. yes, there's a limit, respect it 💀
• id — hardware queue ID. everyone needs a name 🎀
• sq_tail_slot — current slot to which SQ tail pointer is pointing 👉
• sq_lock — serialize submission queue access. one at a time bestie, no shoving 🔒
• cq_tail_slot — current slot to which CQ tail pointer is pointing
• cq_head_slot — current slot to which CQ head pointer is pointing
• cq_lock — Synchronize between multiple polling instances. sharing is caring, locking is essential 🤝
• sq_mutex — prevent submission queue concurrent access. the bouncer at the club 🧚

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🌈 SEE ALSO 🌈

Kernel file ./include/ufs/ufshcd.h, plus the whole friend group:

• struct uic_command(9)
• struct ufshcd_lrb(9)
• struct ufs_query_req(9)
• struct ufs_query_res(9)
• struct ufs_query(9)
• struct ufs_dev_cmd(9)
• struct ufs_clk_info(9)
• struct tx_eqtr_iter(9)
• struct ufshcd_tx_eq_settings(9)
• struct ufshcd_tx_eqtr_data(9)
• struct ufshcd_tx_eqtr_record(9)
• struct ufshcd_tx_eq_params(9)
• struct ufs_hba_variant_ops(9)
• struct ufs_clk_gating(9)
• struct ufs_clk_scaling(9)
• struct ufs_event_hist(9)
• struct ufs_stats(9)
• enum ufshcd_state(9)
• enum ufshcd_pmc_policy(9)
• struct ufshcd_mcq_opr_info_t(9)
• struct ufs_hba(9)
• ufshcd_rmwl(9)
• ufshcd_set_variant(9)
• ufshcd_get_variant(9)

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and that's the page bestie 💜 this one lives in ./include/ufs and the source/version situation is October 2026 — so yeah, timestamped and iconic, struct ufs_hw_queue(9) forever 🌟 slay 🫶