C++ (Cpp) pfn_is_ram Examples

Example #1

File: vmcore.c Project: garyvan/openwrt-1.6

/* Reads a page from the oldmem device from given offset. */
static ssize_t read_from_oldmem(char *buf, size_t count,
				u64 *ppos, int userbuf)
{
	unsigned long pfn, offset;
	size_t nr_bytes;
	ssize_t read = 0, tmp;

	if (!count)
		return 0;

	offset = (unsigned long)(*ppos % PAGE_SIZE);
	pfn = (unsigned long)(*ppos / PAGE_SIZE);

	do {
		if (count > (PAGE_SIZE - offset))
			nr_bytes = PAGE_SIZE - offset;
		else
			nr_bytes = count;

		/* If pfn is not ram, return zeros for sparse dump files */
		if (pfn_is_ram(pfn) == 0) {
			if (userbuf) {
				if (clear_user((char __force_user *)buf, nr_bytes))
					return -EFAULT;
			} else
				memset(buf, 0, nr_bytes);
		} else {
			tmp = copy_oldmem_page(pfn, buf, nr_bytes,
						offset, userbuf);
			if (tmp < 0)
				return tmp;
		}
		*ppos += nr_bytes;
		count -= nr_bytes;
		buf += nr_bytes;
		read += nr_bytes;
		++pfn;
		offset = 0;
	} while (count);

	return read;
}

Example #2

File: vmcore.c Project: MiniBlu/cm11_kernel_htc_msm8974a3ul

static ssize_t read_from_oldmem(char *buf, size_t count,
                                u64 *ppos, int userbuf)
{
    unsigned long pfn, offset;
    size_t nr_bytes;
    ssize_t read = 0, tmp;

    if (!count)
        return 0;

    offset = (unsigned long)(*ppos % PAGE_SIZE);
    pfn = (unsigned long)(*ppos / PAGE_SIZE);

    do {
        if (count > (PAGE_SIZE - offset))
            nr_bytes = PAGE_SIZE - offset;
        else
            nr_bytes = count;


        if (pfn_is_ram(pfn) == 0)
            memset(buf, 0, nr_bytes);
        else {
            tmp = copy_oldmem_page(pfn, buf, nr_bytes,
                                   offset, userbuf);
            if (tmp < 0)
                return tmp;
        }
        *ppos += nr_bytes;
        count -= nr_bytes;
        buf += nr_bytes;
        read += nr_bytes;
        ++pfn;
        offset = 0;
    } while (count);

    return read;
}