linux-headers (unknown)

(root)/
include/
linux/
watch_queue.h
       1  /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
       2  #ifndef _LINUX_WATCH_QUEUE_H
       3  #define _LINUX_WATCH_QUEUE_H
       4  
       5  #include <linux/types.h>
       6  #include <linux/fcntl.h>
       7  #include <linux/ioctl.h>
       8  
       9  #define O_NOTIFICATION_PIPE	O_EXCL	/* Parameter to pipe2() selecting notification pipe */
      10  
      11  #define IOC_WATCH_QUEUE_SET_SIZE	_IO('W', 0x60)	/* Set the size in pages */
      12  #define IOC_WATCH_QUEUE_SET_FILTER	_IO('W', 0x61)	/* Set the filter */
      13  
      14  enum watch_notification_type {
      15  	WATCH_TYPE_META		= 0,	/* Special record */
      16  	WATCH_TYPE_KEY_NOTIFY	= 1,	/* Key change event notification */
      17  	WATCH_TYPE__NR		= 2
      18  };
      19  
      20  enum watch_meta_notification_subtype {
      21  	WATCH_META_REMOVAL_NOTIFICATION	= 0,	/* Watched object was removed */
      22  	WATCH_META_LOSS_NOTIFICATION	= 1,	/* Data loss occurred */
      23  };
      24  
      25  /*
      26   * Notification record header.  This is aligned to 64-bits so that subclasses
      27   * can contain __u64 fields.
      28   */
      29  struct watch_notification {
      30  	__u32			type:24;	/* enum watch_notification_type */
      31  	__u32			subtype:8;	/* Type-specific subtype (filterable) */
      32  	__u32			info;
      33  #define WATCH_INFO_LENGTH	0x0000007f	/* Length of record */
      34  #define WATCH_INFO_LENGTH__SHIFT 0
      35  #define WATCH_INFO_ID		0x0000ff00	/* ID of watchpoint */
      36  #define WATCH_INFO_ID__SHIFT	8
      37  #define WATCH_INFO_TYPE_INFO	0xffff0000	/* Type-specific info */
      38  #define WATCH_INFO_TYPE_INFO__SHIFT 16
      39  #define WATCH_INFO_FLAG_0	0x00010000	/* Type-specific info, flag bit 0 */
      40  #define WATCH_INFO_FLAG_1	0x00020000	/* ... */
      41  #define WATCH_INFO_FLAG_2	0x00040000
      42  #define WATCH_INFO_FLAG_3	0x00080000
      43  #define WATCH_INFO_FLAG_4	0x00100000
      44  #define WATCH_INFO_FLAG_5	0x00200000
      45  #define WATCH_INFO_FLAG_6	0x00400000
      46  #define WATCH_INFO_FLAG_7	0x00800000
      47  };
      48  
      49  /*
      50   * Notification filtering rules (IOC_WATCH_QUEUE_SET_FILTER).
      51   */
      52  struct watch_notification_type_filter {
      53  	__u32	type;			/* Type to apply filter to */
      54  	__u32	info_filter;		/* Filter on watch_notification::info */
      55  	__u32	info_mask;		/* Mask of relevant bits in info_filter */
      56  	__u32	subtype_filter[8];	/* Bitmask of subtypes to filter on */
      57  };
      58  
      59  struct watch_notification_filter {
      60  	__u32	nr_filters;		/* Number of filters */
      61  	__u32	__reserved;		/* Must be 0 */
      62  	struct watch_notification_type_filter filters[];
      63  };
      64  
      65  
      66  /*
      67   * Extended watch removal notification.  This is used optionally if the type
      68   * wants to indicate an identifier for the object being watched, if there is
      69   * such.  This can be distinguished by the length.
      70   *
      71   * type -> WATCH_TYPE_META
      72   * subtype -> WATCH_META_REMOVAL_NOTIFICATION
      73   */
      74  struct watch_notification_removal {
      75  	struct watch_notification watch;
      76  	__u64	id;		/* Type-dependent identifier */
      77  };
      78  
      79  /*
      80   * Type of key/keyring change notification.
      81   */
      82  enum key_notification_subtype {
      83  	NOTIFY_KEY_INSTANTIATED	= 0, /* Key was instantiated (aux is error code) */
      84  	NOTIFY_KEY_UPDATED	= 1, /* Key was updated */
      85  	NOTIFY_KEY_LINKED	= 2, /* Key (aux) was added to watched keyring */
      86  	NOTIFY_KEY_UNLINKED	= 3, /* Key (aux) was removed from watched keyring */
      87  	NOTIFY_KEY_CLEARED	= 4, /* Keyring was cleared */
      88  	NOTIFY_KEY_REVOKED	= 5, /* Key was revoked */
      89  	NOTIFY_KEY_INVALIDATED	= 6, /* Key was invalidated */
      90  	NOTIFY_KEY_SETATTR	= 7, /* Key's attributes got changed */
      91  };
      92  
      93  /*
      94   * Key/keyring notification record.
      95   * - watch.type = WATCH_TYPE_KEY_NOTIFY
      96   * - watch.subtype = enum key_notification_type
      97   */
      98  struct key_notification {
      99  	struct watch_notification watch;
     100  	__u32	key_id;		/* The key/keyring affected */
     101  	__u32	aux;		/* Per-type auxiliary data */
     102  };
     103  
     104  #endif /* _LINUX_WATCH_QUEUE_H */