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oasis-root

Compiled tree of Oasis Linux based on own branch at <https://hacktivis.me/git/oasis/> git clone https://anongit.hacktivis.me/git/oasis-root.git

gntalloc.h (2679B)

    

  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.  */
  11. #ifndef __LINUX_PUBLIC_GNTALLOC_H__
  12. #define __LINUX_PUBLIC_GNTALLOC_H__
  14. #include <linux/types.h>
  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. */
  24. 	__u16 domid;
  25. 	/* Flags for this mapping */
  26. 	__u16 flags;
  27. 	/* Number of pages to map */
  28. 	__u32 count;
  29. 	/* OUT parameters */
  30. 	/* The offset to be used on a subsequent call to mmap(). */
  31. 	__u64 index;
  32. 	/* The grant references of the newly created grant, one per page */
  33. 	/* Variable size, depending on count */
  34. 	union {
  35. 		__u32 gref_ids[1];
  36. 		__DECLARE_FLEX_ARRAY(__u32, gref_ids_flex);
  37. 	};
  38. };
  40. #define GNTALLOC_FLAG_WRITABLE 1
  42. /*
  43.  * Deallocates the grant reference, allowing the associated page to be freed if
  44.  * no other domains are using it.
  45.  */
  46. #define IOCTL_GNTALLOC_DEALLOC_GREF \
  47. _IOC(_IOC_NONE, 'G', 6, sizeof(struct ioctl_gntalloc_dealloc_gref))
  48. struct ioctl_gntalloc_dealloc_gref {
  49. 	/* IN parameters */
  50. 	/* The offset returned in the map operation */
  51. 	__u64 index;
  52. 	/* Number of references to unmap */
  53. 	__u32 count;
  54. };
  56. /*
  57.  * Sets up an unmap notification within the page, so that the other side can do
  58.  * cleanup if this side crashes. Required to implement cross-domain robust
  59.  * mutexes or close notification on communication channels.
  60.  *
  61.  * Each mapped page only supports one notification; multiple calls referring to
  62.  * the same page overwrite the previous notification. You must clear the
  63.  * notification prior to the IOCTL_GNTALLOC_DEALLOC_GREF if you do not want it
  64.  * to occur.
  65.  */
  66. #define IOCTL_GNTALLOC_SET_UNMAP_NOTIFY \
  67. _IOC(_IOC_NONE, 'G', 7, sizeof(struct ioctl_gntalloc_unmap_notify))
  68. struct ioctl_gntalloc_unmap_notify {
  69. 	/* IN parameters */
  70. 	/* Offset in the file descriptor for a byte within the page (same as
  71. 	 * used in mmap). If using UNMAP_NOTIFY_CLEAR_BYTE, this is the byte to
  72. 	 * be cleared. Otherwise, it can be any byte in the page whose
  73. 	 * notification we are adjusting.
  74. 	 */
  75. 	__u64 index;
  76. 	/* Action(s) to take on unmap */
  77. 	__u32 action;
  78. 	/* Event channel to notify */
  79. 	__u32 event_channel_port;
  80. };
  82. /* Clear (set to zero) the byte specified by index */
  83. #define UNMAP_NOTIFY_CLEAR_BYTE 0x1
  84. /* Send an interrupt on the indicated event channel */
  85. #define UNMAP_NOTIFY_SEND_EVENT 0x2
  87. #endif /* __LINUX_PUBLIC_GNTALLOC_H__ */