Subversion Repositories Kolibri OS

#define KMAP_MAX    256

static struct mutex kmap_mutex;

static struct page* kmap_table[KMAP_MAX];

static int kmap_av;

static int kmap_first;

static void* kmap_base;

int kmap_init()

{

    kmap_base = AllocKernelSpace(KMAP_MAX*4096);

    if(kmap_base == NULL)

        return -1;

    kmap_av = KMAP_MAX;

    MutexInit(&kmap_mutex);

    return 0;

};

void *kmap(struct page *page)

{

    void *vaddr = NULL;

    int i;

    do

    {

        MutexLock(&kmap_mutex);

        if(kmap_av != 0)

        {

            for(i = kmap_first; i < KMAP_MAX; i++)

            {

                if(kmap_table[i] == NULL)

                {

                    kmap_av--;

                    kmap_first = i;

                    kmap_table[i] = page;

                    vaddr = kmap_base + (i<<12);

                    MapPage(vaddr,(addr_t)page,3);

                    break;

                };

            };

        };

        MutexUnlock(&kmap_mutex);

    }while(vaddr == NULL);

    return vaddr;

};

void *kmap_atomic(struct page *page) __attribute__ ((alias ("kmap")));

void kunmap(struct page *page)

{

    void *vaddr;

    int   i;

    MutexLock(&kmap_mutex);

    for(i = 0; i < KMAP_MAX; i++)

    {

        if(kmap_table[i] == page)

        {

            kmap_av++;

            if(i < kmap_first)

                kmap_first = i;

            kmap_table[i] = NULL;

            vaddr = kmap_base + (i<<12);

            MapPage(vaddr,0,0);

            break;

        };

    };

    MutexUnlock(&kmap_mutex);

};

void kunmap_atomic(void *vaddr)

{

    int i;

    MapPage(vaddr,0,0);

    i = (vaddr - kmap_base) >> 12;

    MutexLock(&kmap_mutex);

    kmap_av++;

    if(i < kmap_first)

        kmap_first = i;

    kmap_table[i] = NULL;