STRUCT GSI_TRANS(9)

✨ struct gsi_trans 💅 — a GSI transaction, bestie ✨

okay so this is a page from the Kernel API Manual about struct gsi_trans(9), which is, like, literally a GSI transaction. it's giving "kernel internals but make it cute" and honestly? we're obsessed. let's get into it 🎀

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🌸 NAME 🌸

struct gsi_trans — a GSI transaction. that's it, that's the gig ✨

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🦋 SYNOPSIS 🦋

here's the whole struct, copied exactly, no cap:

struct gsi_trans {
    struct gsi *gsi;
    u8 channel_id;
    bool cancelled;
    u8 rsvd_count;
    u8 used_count;
    u32 len;
    union {
      void *data;
      u8 cmd_opcode[IPA_COMMAND_TRANS_TRE_MAX];
    };
    struct scatterlist *sgl;
    enum dma_data_direction direction;
    refcount_t refcount;
    struct completion completion;
    u64 byte_count;
    u64 trans_count;
 };

like, look at her. main character struct energy fr fr 👑

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💖 Members 💖

okay bestie, field-by-field, let's go:

• gsi — the GSI pointer. your ride-or-die back to the GSI, iykyk.
• channel_id — channel number this transaction is associated with 🎀
• cancelled — if the core code sets this, it means the transaction was cancelled. dramatic but valid 💀
• rsvd_count — how many TREs got reserved for this transaction.
• used_count — how many TREs are used — and yes, it could be less than rsvd_count. lowkey flexible like that ✨
• len — number of bytes sent or received by the transaction.
• {unnamed_union} — anonymous. she doesn't need a name, she's mysterious like that 🙈
• data — preserved but not touched by the core transaction code. hands off, she's not yours 🫶
• cmd_opcode — array of command opcodes (command channel only, okay? only there 💅).
• sgl — an array of scatter/gather entries managed by the core code.
• direction — DMA transfer direction (DMA_NONE for commands).
• refcount — reference count used for destruction. this one's important, don't ghost it 😭
• completion — completed when the transaction completes. yes, that's the sentence. it's giving tautology but it's correct 🌈
• byte_count — TX channel byte count recorded when the transaction was committed.
• trans_count — channel transaction count when committed (for BQL accounting). numbers girlies rise ⭐

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🔥 Description 🔥

heads up: most fields in this structure are for internal use by the transaction core code. so like, don't go poking around in there unless you know what you're doing, bestie 💀

the len field gets set when the transaction is committed. and for RX transactions, it gets updated later to reflect the actual number of bytes received — so it's a little "we'll know when we know" situation ✨

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🧚 SEE ALSO 🧚

kernel file ./drivers/net/ipa/gsi_trans.h, plus the whole friend group right here — go say hi:

• gsi_trans_pool_init(9)
• gsi_trans_pool_alloc(9)
• gsi_trans_pool_exit(9)
• gsi_trans_pool_init_dma(9)
• gsi_trans_pool_alloc_dma(9)
• gsi_trans_pool_exit_dma(9)
• gsi_channel_trans_idle(9)
• gsi_channel_trans_alloc(9)
• gsi_trans_free(9)
• gsi_trans_cmd_add(9)
• gsi_trans_page_add(9)
• gsi_trans_skb_add(9)
• gsi_trans_commit(9)
• gsi_trans_commit_wait(9)
• gsi_trans_read_byte(9)
• gsi_trans_read_byte_done(9)

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okay that's the whole page, you ate that 🍓 this one lives in ./drivers/net/ipa and it's dated October 2026 — so like, future vibes, we love that for us 💜 slay, periodt, go read the actual kernel source now 💅✨