1 /* 2 * Copyright (c) 2011 Google, Inc. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 /* 28 * Device descriptor for partitioned disks. To use, set the 29 * d_slice and d_partition variables as follows: 30 * 31 * Whole disk access: 32 * 33 * d_slice = D_SLICENONE 34 * d_partition = <doesn't matter> 35 * 36 * Whole MBR slice: 37 * 38 * d_slice = MBR slice number (typically 1..4) 39 * d_partition = D_PARTNONE 40 * 41 * VTOC disklabel partition within an MBR slice: 42 * 43 * d_slice = MBR slice number (typically 1..4) 44 * d_partition = disklabel partition (typically 0..19 or D_PARTWILD) 45 * 46 * BSD disklabel partition within an MBR slice: 47 * 48 * d_slice = MBR slice number (typically 1..4) 49 * d_partition = disklabel partition (typically 0..19 or D_PARTWILD) 50 * 51 * BSD disklabel partition on the true dedicated disk: 52 * 53 * d_slice = D_SLICENONE 54 * d_partition = disklabel partition (typically 0..19 or D_PARTWILD) 55 * 56 * GPT partition: 57 * 58 * d_slice = GPT partition number (typically 1..N) 59 * d_partition = D_PARTISGPT 60 * 61 * For MBR, setting d_partition to D_PARTWILD will automatically use the first 62 * partition within the slice. 63 * 64 * For both MBR and GPT, to automatically find the 'best' slice and partition, 65 * set d_slice to D_SLICEWILD. This uses the partition type to decide which 66 * partition to use according to the following list of preferences: 67 * 68 * Solaris2 (active) 69 * Solaris2 (inactive) 70 * Linux (active) 71 * Linux (inactive) 72 * DOS/Windows (active) 73 * DOS/Windows (inactive) 74 * 75 * Active MBR slices (marked as bootable) are preferred over inactive. GPT 76 * doesn't have the concept of active/inactive partitions. In both MBR and GPT, 77 * if there are multiple slices/partitions of a given type, the first one 78 * is chosen. 79 * 80 * The low-level disk device will typically call disk_open() from its open 81 * method to interpret the disk partition tables according to the rules above. 82 * This will initialize d_offset to the block offset of the start of the 83 * selected partition - this offset should be added to the offset passed to 84 * the device's strategy method. 85 */ 86 87 #ifndef _DISK_H 88 #define _DISK_H 89 90 #define D_SLICENONE -1 91 #define D_SLICEWILD 0 92 #define D_PARTNONE -1 93 #define D_PARTWILD -2 94 #define D_PARTISGPT 255 95 96 struct disk_devdesc { 97 struct devdesc dd; /* Must be first. */ 98 int d_slice; 99 int d_partition; 100 uint64_t d_offset; 101 }; 102 103 enum disk_ioctl { 104 IOCTL_GET_BLOCKS, 105 IOCTL_GET_BLOCK_SIZE 106 }; 107 108 /* 109 * Parse disk metadata and initialise dev->d_offset. 110 */ 111 extern int disk_open(struct disk_devdesc *, uint64_t, u_int); 112 extern int disk_close(struct disk_devdesc *); 113 extern int disk_ioctl(struct disk_devdesc *, u_long, void *); 114 extern int disk_read(struct disk_devdesc *, void *, uint64_t, u_int); 115 extern int disk_write(struct disk_devdesc *, void *, uint64_t, u_int); 116 117 /* 118 * Print information about slices on a disk. 119 */ 120 extern int disk_print(struct disk_devdesc *, char *, int); 121 extern char* disk_fmtdev(struct disk_devdesc *); 122 extern int disk_parsedev(struct disk_devdesc *, const char *, const char **); 123 124 #endif /* _DISK_H */ 125