Bootstage Runtime Patched Conditionals

include/bootstage_condition.h View source View on GitHub

Structs

bootstage_condition_entry

struct bootstage_condition_entry {
    void                      *code;
    void                      *target;
    enum bootstage_condition  cond;
    enum bootstage            stage;
};

Enums

bootstage_condition

enum bootstage_condition {
    BOOTSTAGE_CONDITION_EQ,
    BOOTSTAGE_CONDITION_LE,
    BOOTSTAGE_CONDITION_LT,
    BOOTSTAGE_CONDITION_GE,
    BOOTSTAGE_CONDITION_GT,
};

Macros

BOOTSTAGE_COND

#define BOOTSTAGE_COND(cond, stage) \
    ({ \
        __label__ l_yes, l_done; \
        bool _taken = false; \
        asm goto("1:\n\t" \
                 ".byte 0xe9\n\t" \
                 ".long %l[l_yes] - (1b + 5)\n\t" \
                 ".pushsection .kernel_bootstage_condition_entries,\"aw\"\n\t" \
                 ".balign 8\n\t" \
                 ".quad 1b\n\t" \
                 ".quad %l[l_yes]\n\t" \
                 ".long %c[op]\n\t" \
                 ".long %c[stg]\n\t" \
                 ".popsection\n\t" \
                 : \
                 : [op] "i"(cond), [stg] "i"(stage) \
                 : \
                 : l_yes); \
        goto l_done; \
    l_yes: \
        _taken = true; \
    l_done: \
        _taken; \
    })

BOOTSTAGE_IF_EQ

#define BOOTSTAGE_IF_EQ(stage) \
    if (BOOTSTAGE_COND(BOOTSTAGE_CONDITION_EQ, stage))

BOOTSTAGE_IF_LE

#define BOOTSTAGE_IF_LE(stage) \
    if (BOOTSTAGE_COND(BOOTSTAGE_CONDITION_LE, stage))

BOOTSTAGE_IF_LT

#define BOOTSTAGE_IF_LT(stage) \
    if (BOOTSTAGE_COND(BOOTSTAGE_CONDITION_LT, stage))

BOOTSTAGE_IF_GE

#define BOOTSTAGE_IF_GE(stage) \
    if (BOOTSTAGE_COND(BOOTSTAGE_CONDITION_GE, stage))

BOOTSTAGE_IF_GT

#define BOOTSTAGE_IF_GT(stage) \
    if (BOOTSTAGE_COND(BOOTSTAGE_CONDITION_GT, stage))

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