hakmem/core/box/ss_slab_management_box.c

// Box: Slab Management (Bitmap Operations)
// Purpose: Slab bitmap manipulation within SuperSlab

#include "ss_slab_management_box.h"

// ============================================================================
// Slab Bitmap Management
// ============================================================================

void superslab_activate_slab(SuperSlab* ss, int slab_idx) {
    if (!ss || slab_idx < 0 || slab_idx >= ss_slabs_capacity(ss)) {
        return;
    }
    uint32_t mask = 1u << slab_idx;
    if ((ss->slab_bitmap & mask) == 0) {
        ss->slab_bitmap |= mask;
        ss->active_slabs++;
    }
}

void superslab_deactivate_slab(SuperSlab* ss, int slab_idx) {
    if (!ss || slab_idx < 0 || slab_idx >= ss_slabs_capacity(ss)) {
        return;
    }
    uint32_t mask = 1u << slab_idx;
    if (ss->slab_bitmap & mask) {
        ss->slab_bitmap &= ~mask;
        ss->active_slabs--;
    }
}

int superslab_find_free_slab(SuperSlab* ss) {
    if (!ss) return -1;
    if ((int)ss->active_slabs >= ss_slabs_capacity(ss)) {
        return -1;  // No free slabs
    }
    // Find first 0 bit in bitmap
    int cap = ss_slabs_capacity(ss);
    for (int i = 0; i < cap; i++) {
        if ((ss->slab_bitmap & (1u << i)) == 0) {
            return i;
        }
    }
    return -1;
}