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1 | /****************************************************************************** |
2 | * gntalloc.h | |
3 | * | |
4 | * Interface to /dev/xen/gntalloc. | |
5 | * | |
6 | * Author: Daniel De Graaf <dgdegra@tycho.nsa.gov> | |
7 | * | |
8 | * This file is in the public domain. | |
9 | */ | |
10 | ||
11 | #ifndef __LINUX_PUBLIC_GNTALLOC_H__ | |
12 | #define __LINUX_PUBLIC_GNTALLOC_H__ | |
13 | ||
91afb7c3 MR |
14 | #include <linux/types.h> |
15 | ||
dd314058 DDG |
16 | /* |
17 | * Allocates a new page and creates a new grant reference. | |
18 | */ | |
19 | #define IOCTL_GNTALLOC_ALLOC_GREF \ | |
20 | _IOC(_IOC_NONE, 'G', 5, sizeof(struct ioctl_gntalloc_alloc_gref)) | |
21 | struct ioctl_gntalloc_alloc_gref { | |
22 | /* IN parameters */ | |
23 | /* The ID of the domain to be given access to the grants. */ | |
91afb7c3 | 24 | __u16 domid; |
dd314058 | 25 | /* Flags for this mapping */ |
91afb7c3 | 26 | __u16 flags; |
dd314058 | 27 | /* Number of pages to map */ |
91afb7c3 | 28 | __u32 count; |
dd314058 DDG |
29 | /* OUT parameters */ |
30 | /* The offset to be used on a subsequent call to mmap(). */ | |
91afb7c3 | 31 | __u64 index; |
dd314058 DDG |
32 | /* The grant references of the newly created grant, one per page */ |
33 | /* Variable size, depending on count */ | |
91afb7c3 | 34 | __u32 gref_ids[1]; |
dd314058 DDG |
35 | }; |
36 | ||
37 | #define GNTALLOC_FLAG_WRITABLE 1 | |
38 | ||
39 | /* | |
40 | * Deallocates the grant reference, allowing the associated page to be freed if | |
41 | * no other domains are using it. | |
42 | */ | |
43 | #define IOCTL_GNTALLOC_DEALLOC_GREF \ | |
44 | _IOC(_IOC_NONE, 'G', 6, sizeof(struct ioctl_gntalloc_dealloc_gref)) | |
45 | struct ioctl_gntalloc_dealloc_gref { | |
46 | /* IN parameters */ | |
47 | /* The offset returned in the map operation */ | |
91afb7c3 | 48 | __u64 index; |
dd314058 | 49 | /* Number of references to unmap */ |
91afb7c3 | 50 | __u32 count; |
dd314058 | 51 | }; |
bdc612dc DDG |
52 | |
53 | /* | |
54 | * Sets up an unmap notification within the page, so that the other side can do | |
55 | * cleanup if this side crashes. Required to implement cross-domain robust | |
56 | * mutexes or close notification on communication channels. | |
57 | * | |
58 | * Each mapped page only supports one notification; multiple calls referring to | |
59 | * the same page overwrite the previous notification. You must clear the | |
60 | * notification prior to the IOCTL_GNTALLOC_DEALLOC_GREF if you do not want it | |
61 | * to occur. | |
62 | */ | |
63 | #define IOCTL_GNTALLOC_SET_UNMAP_NOTIFY \ | |
64 | _IOC(_IOC_NONE, 'G', 7, sizeof(struct ioctl_gntalloc_unmap_notify)) | |
65 | struct ioctl_gntalloc_unmap_notify { | |
66 | /* IN parameters */ | |
67 | /* Offset in the file descriptor for a byte within the page (same as | |
68 | * used in mmap). If using UNMAP_NOTIFY_CLEAR_BYTE, this is the byte to | |
69 | * be cleared. Otherwise, it can be any byte in the page whose | |
70 | * notification we are adjusting. | |
71 | */ | |
91afb7c3 | 72 | __u64 index; |
bdc612dc | 73 | /* Action(s) to take on unmap */ |
91afb7c3 | 74 | __u32 action; |
bdc612dc | 75 | /* Event channel to notify */ |
91afb7c3 | 76 | __u32 event_channel_port; |
bdc612dc DDG |
77 | }; |
78 | ||
79 | /* Clear (set to zero) the byte specified by index */ | |
80 | #define UNMAP_NOTIFY_CLEAR_BYTE 0x1 | |
81 | /* Send an interrupt on the indicated event channel */ | |
82 | #define UNMAP_NOTIFY_SEND_EVENT 0x2 | |
83 | ||
dd314058 | 84 | #endif /* __LINUX_PUBLIC_GNTALLOC_H__ */ |