[XFRM] IPV6: Use distribution counting sort for xfrm_state/xfrm_tmpl chain.

	x->props.family = AF_INET6;

}

/* distribution counting sort function for xfrm_state and xfrm_tmpl */

static int

__xfrm6_state_sort(struct xfrm_state **dst, struct xfrm_state **src, int n)

__xfrm6_sort(void **dst, void **src, int n, int (*cmp)(void *p), int maxclass)

{

	int i;

	int j = 0;

	int class[XFRM_MAX_DEPTH];

	int count[maxclass];

	/* Rule 1: select IPsec transport except AH */

	for (i = 0; i < n; i++) {

		if (src[i]->props.mode == XFRM_MODE_TRANSPORT &&

		    src[i]->id.proto != IPPROTO_AH) {

			dst[j++] = src[i];

			src[i] = NULL;

		}

	}

	if (j == n)

		goto end;

	memset(count, 0, sizeof(count));

	/* Rule 2: select MIPv6 RO or inbound trigger */

#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)

	for (i = 0; i < n; i++) {

		if (src[i] &&

		    (src[i]->props.mode == XFRM_MODE_ROUTEOPTIMIZATION ||

		     src[i]->props.mode == XFRM_MODE_IN_TRIGGER)) {

			dst[j++] = src[i];

			src[i] = NULL;

		}

		int c;

		class[i] = c = cmp(src[i]);

		count[c]++;

	}

	if (j == n)

		goto end;

#endif

	/* Rule 3: select IPsec transport AH */

	for (i = 0; i < n; i++) {

		if (src[i] &&

		    src[i]->props.mode == XFRM_MODE_TRANSPORT &&

		    src[i]->id.proto == IPPROTO_AH) {

			dst[j++] = src[i];

			src[i] = NULL;

		}

	}

	if (j == n)

		goto end;

	for (i = 2; i < maxclass; i++)

		count[i] += count[i - 1];

	/* Rule 4: select IPsec tunnel */

	for (i = 0; i < n; i++) {

		if (src[i] &&

		    (src[i]->props.mode == XFRM_MODE_TUNNEL ||

		     src[i]->props.mode == XFRM_MODE_BEET)) {

			dst[j++] = src[i];

			src[i] = NULL;

		}

		dst[count[class[i] - 1]++] = src[i];

		src[i] = 0;

	}

	if (likely(j == n))

		goto end;

	/* Final rule */

	for (i = 0; i < n; i++) {

		if (src[i]) {

			dst[j++] = src[i];

			src[i] = NULL;

		}

	}

 end:

	return 0;

}

static int

__xfrm6_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n)

/*

 * Rule for xfrm_state:

 *

 * rule 1: select IPsec transport except AH

 * rule 2: select MIPv6 RO or inbound trigger

 * rule 3: select IPsec transport AH

 * rule 4: select IPsec tunnel

 * rule 5: others

 */

static int __xfrm6_state_sort_cmp(void *p)

{

	int i;

	int j = 0;

	/* Rule 1: select IPsec transport */

	for (i = 0; i < n; i++) {

		if (src[i]->mode == XFRM_MODE_TRANSPORT) {

			dst[j++] = src[i];

			src[i] = NULL;

		}

	}

	if (j == n)

		goto end;

	/* Rule 2: select MIPv6 RO or inbound trigger */

	struct xfrm_state *v = p;

	switch (v->props.mode) {

	case XFRM_MODE_TRANSPORT:

		if (v->id.proto != IPPROTO_AH)

			return 1;

		else

			return 3;

#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)

	for (i = 0; i < n; i++) {

		if (src[i] &&

		    (src[i]->mode == XFRM_MODE_ROUTEOPTIMIZATION ||

		     src[i]->mode == XFRM_MODE_IN_TRIGGER)) {

			dst[j++] = src[i];

			src[i] = NULL;

	case XFRM_MODE_ROUTEOPTIMIZATION:

	case XFRM_MODE_IN_TRIGGER:

		return 2;

#endif

	case XFRM_MODE_TUNNEL:

	case XFRM_MODE_BEET:

		return 4;

	}

	return 5;

}

	if (j == n)

		goto end;

#endif

	/* Rule 3: select IPsec tunnel */

	for (i = 0; i < n; i++) {

		if (src[i] &&

		    (src[i]->mode == XFRM_MODE_TUNNEL ||

		     src[i]->mode == XFRM_MODE_BEET)) {

			dst[j++] = src[i];

			src[i] = NULL;

		}

static int

__xfrm6_state_sort(struct xfrm_state **dst, struct xfrm_state **src, int n)

{

	return __xfrm6_sort((void **)dst, (void **)src, n,

			    __xfrm6_state_sort_cmp, 6);

}

	if (likely(j == n))

		goto end;

	/* Final rule */

	for (i = 0; i < n; i++) {

		if (src[i]) {

			dst[j++] = src[i];

			src[i] = NULL;

/*

 * Rule for xfrm_tmpl:

 *

 * rule 1: select IPsec transport

 * rule 2: select MIPv6 RO or inbound trigger

 * rule 3: select IPsec tunnel

 * rule 4: others

 */

static int __xfrm6_tmpl_sort_cmp(void *p)

{

	struct xfrm_tmpl *v = p;

	switch (v->mode) {

	case XFRM_MODE_TRANSPORT:

		return 1;

#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)

	case XFRM_MODE_ROUTEOPTIMIZATION:

	case XFRM_MODE_IN_TRIGGER:

		return 2;

#endif

	case XFRM_MODE_TUNNEL:

	case XFRM_MODE_BEET:

		return 3;

	}

	return 4;

}

 end:

	return 0;

static int

__xfrm6_tmpl_sort(struct xfrm_tmpl **dst, struct xfrm_tmpl **src, int n)

{

	return __xfrm6_sort((void **)dst, (void **)src, n,

			    __xfrm6_tmpl_sort_cmp, 5);

}

int xfrm6_extract_header(struct sk_buff *skb)