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diff --git a/ANDROID_3.4.5/include/xen/interface/io/ring.h b/ANDROID_3.4.5/include/xen/interface/io/ring.h
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--- a/ANDROID_3.4.5/include/xen/interface/io/ring.h
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-/******************************************************************************
- * ring.h
- *
- * Shared producer-consumer ring macros.
- *
- * Tim Deegan and Andrew Warfield November 2004.
- */
-
-#ifndef __XEN_PUBLIC_IO_RING_H__
-#define __XEN_PUBLIC_IO_RING_H__
-
-typedef unsigned int RING_IDX;
-
-/* Round a 32-bit unsigned constant down to the nearest power of two. */
-#define __RD2(_x) (((_x) & 0x00000002) ? 0x2 : ((_x) & 0x1))
-#define __RD4(_x) (((_x) & 0x0000000c) ? __RD2((_x)>>2)<<2 : __RD2(_x))
-#define __RD8(_x) (((_x) & 0x000000f0) ? __RD4((_x)>>4)<<4 : __RD4(_x))
-#define __RD16(_x) (((_x) & 0x0000ff00) ? __RD8((_x)>>8)<<8 : __RD8(_x))
-#define __RD32(_x) (((_x) & 0xffff0000) ? __RD16((_x)>>16)<<16 : __RD16(_x))
-
-/*
- * Calculate size of a shared ring, given the total available space for the
- * ring and indexes (_sz), and the name tag of the request/response structure.
- * A ring contains as many entries as will fit, rounded down to the nearest
- * power of two (so we can mask with (size-1) to loop around).
- */
-#define __CONST_RING_SIZE(_s, _sz) \
- (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \
- sizeof(((struct _s##_sring *)0)->ring[0])))
-
-/*
- * The same for passing in an actual pointer instead of a name tag.
- */
-#define __RING_SIZE(_s, _sz) \
- (__RD32(((_sz) - (long)&(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
-
-/*
- * Macros to make the correct C datatypes for a new kind of ring.
- *
- * To make a new ring datatype, you need to have two message structures,
- * let's say struct request, and struct response already defined.
- *
- * In a header where you want the ring datatype declared, you then do:
- *
- * DEFINE_RING_TYPES(mytag, struct request, struct response);
- *
- * These expand out to give you a set of types, as you can see below.
- * The most important of these are:
- *
- * struct mytag_sring - The shared ring.
- * struct mytag_front_ring - The 'front' half of the ring.
- * struct mytag_back_ring - The 'back' half of the ring.
- *
- * To initialize a ring in your code you need to know the location and size
- * of the shared memory area (PAGE_SIZE, for instance). To initialise
- * the front half:
- *
- * struct mytag_front_ring front_ring;
- * SHARED_RING_INIT((struct mytag_sring *)shared_page);
- * FRONT_RING_INIT(&front_ring, (struct mytag_sring *)shared_page,
- * PAGE_SIZE);
- *
- * Initializing the back follows similarly (note that only the front
- * initializes the shared ring):
- *
- * struct mytag_back_ring back_ring;
- * BACK_RING_INIT(&back_ring, (struct mytag_sring *)shared_page,
- * PAGE_SIZE);
- */
-
-#define DEFINE_RING_TYPES(__name, __req_t, __rsp_t) \
- \
-/* Shared ring entry */ \
-union __name##_sring_entry { \
- __req_t req; \
- __rsp_t rsp; \
-}; \
- \
-/* Shared ring page */ \
-struct __name##_sring { \
- RING_IDX req_prod, req_event; \
- RING_IDX rsp_prod, rsp_event; \
- uint8_t pad[48]; \
- union __name##_sring_entry ring[1]; /* variable-length */ \
-}; \
- \
-/* "Front" end's private variables */ \
-struct __name##_front_ring { \
- RING_IDX req_prod_pvt; \
- RING_IDX rsp_cons; \
- unsigned int nr_ents; \
- struct __name##_sring *sring; \
-}; \
- \
-/* "Back" end's private variables */ \
-struct __name##_back_ring { \
- RING_IDX rsp_prod_pvt; \
- RING_IDX req_cons; \
- unsigned int nr_ents; \
- struct __name##_sring *sring; \
-};
-
-/*
- * Macros for manipulating rings.
- *
- * FRONT_RING_whatever works on the "front end" of a ring: here
- * requests are pushed on to the ring and responses taken off it.
- *
- * BACK_RING_whatever works on the "back end" of a ring: here
- * requests are taken off the ring and responses put on.
- *
- * N.B. these macros do NO INTERLOCKS OR FLOW CONTROL.
- * This is OK in 1-for-1 request-response situations where the
- * requestor (front end) never has more than RING_SIZE()-1
- * outstanding requests.
- */
-
-/* Initialising empty rings */
-#define SHARED_RING_INIT(_s) do { \
- (_s)->req_prod = (_s)->rsp_prod = 0; \
- (_s)->req_event = (_s)->rsp_event = 1; \
- memset((_s)->pad, 0, sizeof((_s)->pad)); \
-} while(0)
-
-#define FRONT_RING_INIT(_r, _s, __size) do { \
- (_r)->req_prod_pvt = 0; \
- (_r)->rsp_cons = 0; \
- (_r)->nr_ents = __RING_SIZE(_s, __size); \
- (_r)->sring = (_s); \
-} while (0)
-
-#define BACK_RING_INIT(_r, _s, __size) do { \
- (_r)->rsp_prod_pvt = 0; \
- (_r)->req_cons = 0; \
- (_r)->nr_ents = __RING_SIZE(_s, __size); \
- (_r)->sring = (_s); \
-} while (0)
-
-/* Initialize to existing shared indexes -- for recovery */
-#define FRONT_RING_ATTACH(_r, _s, __size) do { \
- (_r)->sring = (_s); \
- (_r)->req_prod_pvt = (_s)->req_prod; \
- (_r)->rsp_cons = (_s)->rsp_prod; \
- (_r)->nr_ents = __RING_SIZE(_s, __size); \
-} while (0)
-
-#define BACK_RING_ATTACH(_r, _s, __size) do { \
- (_r)->sring = (_s); \
- (_r)->rsp_prod_pvt = (_s)->rsp_prod; \
- (_r)->req_cons = (_s)->req_prod; \
- (_r)->nr_ents = __RING_SIZE(_s, __size); \
-} while (0)
-
-/* How big is this ring? */
-#define RING_SIZE(_r) \
- ((_r)->nr_ents)
-
-/* Number of free requests (for use on front side only). */
-#define RING_FREE_REQUESTS(_r) \
- (RING_SIZE(_r) - ((_r)->req_prod_pvt - (_r)->rsp_cons))
-
-/* Test if there is an empty slot available on the front ring.
- * (This is only meaningful from the front. )
- */
-#define RING_FULL(_r) \
- (RING_FREE_REQUESTS(_r) == 0)
-
-/* Test if there are outstanding messages to be processed on a ring. */
-#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
- ((_r)->sring->rsp_prod - (_r)->rsp_cons)
-
-#define RING_HAS_UNCONSUMED_REQUESTS(_r) \
- ({ \
- unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
- unsigned int rsp = RING_SIZE(_r) - \
- ((_r)->req_cons - (_r)->rsp_prod_pvt); \
- req < rsp ? req : rsp; \
- })
-
-/* Direct access to individual ring elements, by index. */
-#define RING_GET_REQUEST(_r, _idx) \
- (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
-
-#define RING_GET_RESPONSE(_r, _idx) \
- (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].rsp))
-
-/* Loop termination condition: Would the specified index overflow the ring? */
-#define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \
- (((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r))
-
-#define RING_PUSH_REQUESTS(_r) do { \
- wmb(); /* back sees requests /before/ updated producer index */ \
- (_r)->sring->req_prod = (_r)->req_prod_pvt; \
-} while (0)
-
-#define RING_PUSH_RESPONSES(_r) do { \
- wmb(); /* front sees responses /before/ updated producer index */ \
- (_r)->sring->rsp_prod = (_r)->rsp_prod_pvt; \
-} while (0)
-
-/*
- * Notification hold-off (req_event and rsp_event):
- *
- * When queueing requests or responses on a shared ring, it may not always be
- * necessary to notify the remote end. For example, if requests are in flight
- * in a backend, the front may be able to queue further requests without
- * notifying the back (if the back checks for new requests when it queues
- * responses).
- *
- * When enqueuing requests or responses:
- *
- * Use RING_PUSH_{REQUESTS,RESPONSES}_AND_CHECK_NOTIFY(). The second argument
- * is a boolean return value. True indicates that the receiver requires an
- * asynchronous notification.
- *
- * After dequeuing requests or responses (before sleeping the connection):
- *
- * Use RING_FINAL_CHECK_FOR_REQUESTS() or RING_FINAL_CHECK_FOR_RESPONSES().
- * The second argument is a boolean return value. True indicates that there
- * are pending messages on the ring (i.e., the connection should not be put
- * to sleep).
- *
- * These macros will set the req_event/rsp_event field to trigger a
- * notification on the very next message that is enqueued. If you want to
- * create batches of work (i.e., only receive a notification after several
- * messages have been enqueued) then you will need to create a customised
- * version of the FINAL_CHECK macro in your own code, which sets the event
- * field appropriately.
- */
-
-#define RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(_r, _notify) do { \
- RING_IDX __old = (_r)->sring->req_prod; \
- RING_IDX __new = (_r)->req_prod_pvt; \
- wmb(); /* back sees requests /before/ updated producer index */ \
- (_r)->sring->req_prod = __new; \
- mb(); /* back sees new requests /before/ we check req_event */ \
- (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \
- (RING_IDX)(__new - __old)); \
-} while (0)
-
-#define RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(_r, _notify) do { \
- RING_IDX __old = (_r)->sring->rsp_prod; \
- RING_IDX __new = (_r)->rsp_prod_pvt; \
- wmb(); /* front sees responses /before/ updated producer index */ \
- (_r)->sring->rsp_prod = __new; \
- mb(); /* front sees new responses /before/ we check rsp_event */ \
- (_notify) = ((RING_IDX)(__new - (_r)->sring->rsp_event) < \
- (RING_IDX)(__new - __old)); \
-} while (0)
-
-#define RING_FINAL_CHECK_FOR_REQUESTS(_r, _work_to_do) do { \
- (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
- if (_work_to_do) break; \
- (_r)->sring->req_event = (_r)->req_cons + 1; \
- mb(); \
- (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
-} while (0)
-
-#define RING_FINAL_CHECK_FOR_RESPONSES(_r, _work_to_do) do { \
- (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
- if (_work_to_do) break; \
- (_r)->sring->rsp_event = (_r)->rsp_cons + 1; \
- mb(); \
- (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
-} while (0)
-
-#endif /* __XEN_PUBLIC_IO_RING_H__ */
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