core/hfs_hotfiles.h

   1 /*
   2  * Copyright (c) 2003-2015 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 #ifndef __HFS_HOTFILES__
  29 #define __HFS_HOTFILES__
  30
  31 #include <sys/appleapiopts.h>
  32
  33 #ifdef KERNEL
  34 #ifdef __APPLE_API_PRIVATE
  35
  36
  37 #define HFC_FILENAME    ".hotfiles.btree"
  38
  39
  40 /*
  41  * Temperature measurement constraints.
  42  */
  43 #define HFC_DEFAULT_FILE_COUNT   hfc_default_file_count
  44 #define HFC_DEFAULT_DURATION     hfc_default_duration
  45 #define HFC_CUMULATIVE_CYCLES    3
  46 #define HFC_MAXIMUM_FILE_COUNT   hfc_max_file_count
  47 #define HFC_MAXIMUM_FILESIZE     hfc_max_file_size
  48 #define HFC_MINIMUM_TEMPERATURE  24
  49
  50
  51 /*
  52  * Sync constraints.
  53  */
  54 #define HFC_BLKSPERSYNC    300
  55 #define HFC_FILESPERSYNC   50
  56
  57
  58 /*
  59  * Hot file clustering stages.
  60  */
  61 enum hfc_stage {
  62         HFC_DISABLED,
  63         HFC_IDLE,
  64         HFC_BUSY,
  65         HFC_RECORDING,
  66         HFC_EVALUATION,
  67         HFC_EVICTION,
  68         HFC_ADOPTION,
  69 };
  70
  71
  72 /*
  73  * B-tree file key format (on-disk).
  74  */
  75 struct HotFileKey {
  76         u_int16_t       keyLength;      /* length of key, excluding this field */
  77         u_int8_t        forkType;       /* 0 = data fork, FF = resource fork */
  78         u_int8_t        pad;            /* make the other fields align on 32-bit boundary */
  79         u_int32_t       temperature;    /* temperature recorded */
  80         u_int32_t       fileID;         /* file ID */
  81 };
  82 typedef struct HotFileKey HotFileKey;
  83
  84 #define HFC_LOOKUPTAG   0xFFFFFFFF
  85 #define HFC_KEYLENGTH   (sizeof(HotFileKey) - sizeof(u_int16_t))
  86
  87 /*
  88  * B-tree header node user info (on-disk).
  89  */
  90 struct HotFilesInfo {
  91         u_int32_t       magic;
  92         u_int32_t       version;
  93         u_int32_t       duration;    /* duration of sample period (secs) */
  94         u_int32_t       timebase;    /* start of recording period (GMT time in secs) */
  95         u_int32_t       timeleft;    /* time remaining in recording period (secs) */
  96         u_int32_t       threshold;
  97         u_int32_t       maxfileblks;
  98         union {
  99                 u_int32_t       _maxfilecnt;   // on hdd's we track the max # of files
 100                 u_int32_t       _usedblocks;   // on ssd's we track how many blocks are used
 101         } _u;
 102         u_int8_t        tag[32];
 103 };
 104
 105 #define usedblocks _u._usedblocks
 106 #define maxfilecnt _u._maxfilecnt
 107
 108 typedef struct HotFilesInfo HotFilesInfo;
 109
 110 #define HFC_MAGIC       0xFF28FF26
 111 #define HFC_VERSION     1
 112
 113
 114 struct hfsmount;
 115 struct proc;
 116 struct vnode;
 117
 118 /*
 119  * Hot File interface functions.
 120  */
 121 int  hfs_hotfilesync (struct hfsmount *, vfs_context_t ctx);
 122
 123 int  hfs_recording_init(struct hfsmount *);
 124 int  hfs_recording_suspend (struct hfsmount *);
 125
 126 int  hfs_addhotfile (struct vnode *);
 127 int  hfs_removehotfile (struct vnode *);
 128 int  hfs_hotfile_deleted(struct vnode *vp);   // called when a file is deleted
 129 void hfs_repin_hotfiles(struct hfsmount *);
 130
 131 // call this to adjust the number of used hotfile blocks either up/down
 132 int  hfs_hotfile_adjust_blocks(struct vnode *vp, int64_t num_blocks);
 133
 134 #endif /* __APPLE_API_PRIVATE */
 135 #endif /* KERNEL */
 136 #endif /* __HFS_HOTFILES__ */