1 /********************************************* 1 /******************************************************************************
2 * gntalloc.h 2 * gntalloc.h
3 * 3 *
4 * Interface to /dev/xen/gntalloc. 4 * Interface to /dev/xen/gntalloc.
5 * 5 *
6 * Author: Daniel De Graaf <dgdegra@tycho.nsa. 6 * Author: Daniel De Graaf <dgdegra@tycho.nsa.gov>
7 * 7 *
8 * This file is in the public domain. 8 * This file is in the public domain.
9 */ 9 */
10 10
11 #ifndef __LINUX_PUBLIC_GNTALLOC_H__ 11 #ifndef __LINUX_PUBLIC_GNTALLOC_H__
12 #define __LINUX_PUBLIC_GNTALLOC_H__ 12 #define __LINUX_PUBLIC_GNTALLOC_H__
13 13
14 #include <linux/types.h> 14 #include <linux/types.h>
15 15
16 /* 16 /*
17 * Allocates a new page and creates a new gran 17 * Allocates a new page and creates a new grant reference.
18 */ 18 */
19 #define IOCTL_GNTALLOC_ALLOC_GREF \ 19 #define IOCTL_GNTALLOC_ALLOC_GREF \
20 _IOC(_IOC_NONE, 'G', 5, sizeof(struct ioctl_gn 20 _IOC(_IOC_NONE, 'G', 5, sizeof(struct ioctl_gntalloc_alloc_gref))
21 struct ioctl_gntalloc_alloc_gref { 21 struct ioctl_gntalloc_alloc_gref {
22 /* IN parameters */ 22 /* IN parameters */
23 /* The ID of the domain to be given ac 23 /* The ID of the domain to be given access to the grants. */
24 __u16 domid; 24 __u16 domid;
25 /* Flags for this mapping */ 25 /* Flags for this mapping */
26 __u16 flags; 26 __u16 flags;
27 /* Number of pages to map */ 27 /* Number of pages to map */
28 __u32 count; 28 __u32 count;
29 /* OUT parameters */ 29 /* OUT parameters */
30 /* The offset to be used on a subseque 30 /* The offset to be used on a subsequent call to mmap(). */
31 __u64 index; 31 __u64 index;
32 /* The grant references of the newly c 32 /* The grant references of the newly created grant, one per page */
33 /* Variable size, depending on count * 33 /* Variable size, depending on count */
34 union { 34 union {
35 __u32 gref_ids[1]; 35 __u32 gref_ids[1];
36 __DECLARE_FLEX_ARRAY(__u32, gr 36 __DECLARE_FLEX_ARRAY(__u32, gref_ids_flex);
37 }; 37 };
38 }; 38 };
39 39
40 #define GNTALLOC_FLAG_WRITABLE 1 40 #define GNTALLOC_FLAG_WRITABLE 1
41 41
42 /* 42 /*
43 * Deallocates the grant reference, allowing t 43 * Deallocates the grant reference, allowing the associated page to be freed if
44 * no other domains are using it. 44 * no other domains are using it.
45 */ 45 */
46 #define IOCTL_GNTALLOC_DEALLOC_GREF \ 46 #define IOCTL_GNTALLOC_DEALLOC_GREF \
47 _IOC(_IOC_NONE, 'G', 6, sizeof(struct ioctl_gn 47 _IOC(_IOC_NONE, 'G', 6, sizeof(struct ioctl_gntalloc_dealloc_gref))
48 struct ioctl_gntalloc_dealloc_gref { 48 struct ioctl_gntalloc_dealloc_gref {
49 /* IN parameters */ 49 /* IN parameters */
50 /* The offset returned in the map oper 50 /* The offset returned in the map operation */
51 __u64 index; 51 __u64 index;
52 /* Number of references to unmap */ 52 /* Number of references to unmap */
53 __u32 count; 53 __u32 count;
54 }; 54 };
55 55
56 /* 56 /*
57 * Sets up an unmap notification within the pa 57 * Sets up an unmap notification within the page, so that the other side can do
58 * cleanup if this side crashes. Required to i 58 * cleanup if this side crashes. Required to implement cross-domain robust
59 * mutexes or close notification on communicat 59 * mutexes or close notification on communication channels.
60 * 60 *
61 * Each mapped page only supports one notifica 61 * Each mapped page only supports one notification; multiple calls referring to
62 * the same page overwrite the previous notifi 62 * the same page overwrite the previous notification. You must clear the
63 * notification prior to the IOCTL_GNTALLOC_DE 63 * notification prior to the IOCTL_GNTALLOC_DEALLOC_GREF if you do not want it
64 * to occur. 64 * to occur.
65 */ 65 */
66 #define IOCTL_GNTALLOC_SET_UNMAP_NOTIFY \ 66 #define IOCTL_GNTALLOC_SET_UNMAP_NOTIFY \
67 _IOC(_IOC_NONE, 'G', 7, sizeof(struct ioctl_gn 67 _IOC(_IOC_NONE, 'G', 7, sizeof(struct ioctl_gntalloc_unmap_notify))
68 struct ioctl_gntalloc_unmap_notify { 68 struct ioctl_gntalloc_unmap_notify {
69 /* IN parameters */ 69 /* IN parameters */
70 /* Offset in the file descriptor for a 70 /* Offset in the file descriptor for a byte within the page (same as
71 * used in mmap). If using UNMAP_NOTIF 71 * used in mmap). If using UNMAP_NOTIFY_CLEAR_BYTE, this is the byte to
72 * be cleared. Otherwise, it can be an 72 * be cleared. Otherwise, it can be any byte in the page whose
73 * notification we are adjusting. 73 * notification we are adjusting.
74 */ 74 */
75 __u64 index; 75 __u64 index;
76 /* Action(s) to take on unmap */ 76 /* Action(s) to take on unmap */
77 __u32 action; 77 __u32 action;
78 /* Event channel to notify */ 78 /* Event channel to notify */
79 __u32 event_channel_port; 79 __u32 event_channel_port;
80 }; 80 };
81 81
82 /* Clear (set to zero) the byte specified by i 82 /* Clear (set to zero) the byte specified by index */
83 #define UNMAP_NOTIFY_CLEAR_BYTE 0x1 83 #define UNMAP_NOTIFY_CLEAR_BYTE 0x1
84 /* Send an interrupt on the indicated event ch 84 /* Send an interrupt on the indicated event channel */
85 #define UNMAP_NOTIFY_SEND_EVENT 0x2 85 #define UNMAP_NOTIFY_SEND_EVENT 0x2
86 86
87 #endif /* __LINUX_PUBLIC_GNTALLOC_H__ */ 87 #endif /* __LINUX_PUBLIC_GNTALLOC_H__ */
88 88
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