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      1 /*
      2  * Copyright (c) 2013, The Linux Foundation. All rights reserved.
      3  *
      4  * Redistribution and use in source and binary forms, with or without
      5  * modification, are permitted provided that the following conditions are
      6  * met:
      7  *     * Redistributions of source code must retain the above copyright
      8  *       notice, this list of conditions and the following disclaimer.
      9  *     * Redistributions in binary form must reproduce the above
     10  *       copyright notice, this list of conditions and the following
     11  *       disclaimer in the documentation and/or other materials provided
     12  *       with the distribution.
     13  *     * Neither the name of The Linux Foundation nor the names of its
     14  *       contributors may be used to endorse or promote products derived
     15  *       from this software without specific prior written permission.
     16  *
     17  * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
     18  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
     19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
     20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
     21  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     22  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     23  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
     24  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
     25  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
     26  * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
     27  * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     28  */
     29 
     30 #ifndef __GPT_UTILS_H__
     31 #define __GPT_UTILS_H__
     32 #include <vector>
     33 #include <string>
     34 #include <map>
     35 #ifdef __cplusplus
     36 extern "C" {
     37 #endif
     38 #include <unistd.h>
     39 #include <stdlib.h>
     40 /******************************************************************************
     41  * GPT HEADER DEFINES
     42  ******************************************************************************/
     43 #define GPT_SIGNATURE               "EFI PART"
     44 #define HEADER_SIZE_OFFSET          12
     45 #define HEADER_CRC_OFFSET           16
     46 #define PRIMARY_HEADER_OFFSET       24
     47 #define BACKUP_HEADER_OFFSET        32
     48 #define FIRST_USABLE_LBA_OFFSET     40
     49 #define LAST_USABLE_LBA_OFFSET      48
     50 #define PENTRIES_OFFSET             72
     51 #define PARTITION_COUNT_OFFSET      80
     52 #define PENTRY_SIZE_OFFSET          84
     53 #define PARTITION_CRC_OFFSET        88
     54 
     55 #define TYPE_GUID_OFFSET            0
     56 #define TYPE_GUID_SIZE              16
     57 #define PTN_ENTRY_SIZE              128
     58 #define UNIQUE_GUID_OFFSET          16
     59 #define FIRST_LBA_OFFSET            32
     60 #define LAST_LBA_OFFSET             40
     61 #define ATTRIBUTE_FLAG_OFFSET       48
     62 #define PARTITION_NAME_OFFSET       56
     63 #define MAX_GPT_NAME_SIZE           72
     64 
     65 /******************************************************************************
     66  * AB RELATED DEFINES
     67  ******************************************************************************/
     68 //Bit 48 onwords in the attribute field are the ones where we are allowed to
     69 //store our AB attributes.
     70 #define AB_FLAG_OFFSET (ATTRIBUTE_FLAG_OFFSET + 6)
     71 #define GPT_DISK_INIT_MAGIC 0xABCD
     72 #define AB_PARTITION_ATTR_SLOT_ACTIVE (0x1<<2)
     73 #define AB_PARTITION_ATTR_BOOT_SUCCESSFUL (0x1<<6)
     74 #define AB_PARTITION_ATTR_UNBOOTABLE (0x1<<7)
     75 #define AB_SLOT_ACTIVE_VAL              0x3F
     76 #define AB_SLOT_INACTIVE_VAL            0x0
     77 #define AB_SLOT_ACTIVE                  1
     78 #define AB_SLOT_INACTIVE                0
     79 #define AB_SLOT_A_SUFFIX                "_a"
     80 #define AB_SLOT_B_SUFFIX                "_b"
     81 #define PTN_XBL                         "xbl"
     82 #define PTN_SWAP_LIST                   PTN_XBL, "sbl1", "rpm", "tz", "aboot", "hyp", "lksecapp", "keymaster", "cmnlib", "cmnlib32", "cmnlib64", "pmic", "apdp", "devcfg", "hosd", "keystore", "msadp"
     83 #define AB_PTN_LIST PTN_SWAP_LIST, "boot", "system", "vendor", "modem", "bluetooth"
     84 #define BOOT_DEV_DIR    "/dev/block/bootdevice/by-name"
     85 
     86 /******************************************************************************
     87  * HELPER MACROS
     88  ******************************************************************************/
     89 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
     90 /******************************************************************************
     91  * TYPES
     92  ******************************************************************************/
     93 enum boot_update_stage {
     94 	UPDATE_MAIN = 1,
     95 	UPDATE_BACKUP,
     96 	UPDATE_FINALIZE
     97 };
     98 
     99 enum gpt_instance {
    100 	PRIMARY_GPT = 0,
    101 	SECONDARY_GPT
    102 };
    103 
    104 enum boot_chain {
    105 	NORMAL_BOOT = 0,
    106 	BACKUP_BOOT
    107 };
    108 
    109 struct gpt_disk {
    110 	//GPT primary header
    111 	uint8_t *hdr;
    112 	//primary header crc
    113 	uint32_t hdr_crc;
    114 	//GPT backup header
    115 	uint8_t *hdr_bak;
    116 	//backup header crc
    117 	uint32_t hdr_bak_crc;
    118 	//Partition entries array
    119 	uint8_t *pentry_arr;
    120 	//Partition entries array for backup table
    121 	uint8_t *pentry_arr_bak;
    122 	//Size of the pentry array
    123 	uint32_t pentry_arr_size;
    124 	//Size of each element in the pentry array
    125 	uint32_t pentry_size;
    126 	//CRC of the partition entry array
    127 	uint32_t pentry_arr_crc;
    128 	//CRC of the backup partition entry array
    129 	uint32_t pentry_arr_bak_crc;
    130 	//Path to block dev representing the disk
    131 	char devpath[PATH_MAX];
    132 	//Block size of disk
    133 	uint32_t block_size;
    134 	uint32_t is_initialized;
    135 };
    136 
    137 /******************************************************************************
    138  * FUNCTION PROTOTYPES
    139  ******************************************************************************/
    140 int prepare_boot_update(enum boot_update_stage stage);
    141 //GPT disk methods
    142 struct gpt_disk* gpt_disk_alloc();
    143 //Free previously allocated gpt_disk struct
    144 void gpt_disk_free(struct gpt_disk *disk);
    145 //Get the details of the disk holding the partition whose name
    146 //is passed in via dev
    147 int gpt_disk_get_disk_info(const char *dev, struct gpt_disk *disk);
    148 
    149 //Get pointer to partition entry from a allocated gpt_disk structure
    150 uint8_t* gpt_disk_get_pentry(struct gpt_disk *disk,
    151 		const char *partname,
    152 		enum gpt_instance instance);
    153 
    154 //Update the crc fields of the modified disk structure
    155 int gpt_disk_update_crc(struct gpt_disk *disk);
    156 
    157 //Write the contents of struct gpt_disk back to the actual disk
    158 int gpt_disk_commit(struct gpt_disk *disk);
    159 
    160 //Return if the current device is UFS based or not
    161 int gpt_utils_is_ufs_device();
    162 
    163 //Swtich betwieen using either the primary or the backup
    164 //boot LUN for boot. This is required since UFS boot partitions
    165 //cannot have a backup GPT which is what we use for failsafe
    166 //updates of the other 'critical' partitions. This function will
    167 //not be invoked for emmc targets and on UFS targets is only required
    168 //to be invoked for XBL.
    169 //
    170 //The algorithm to do this is as follows:
    171 //- Find the real block device(eg: /dev/block/sdb) that corresponds
    172 //  to the /dev/block/bootdevice/by-name/xbl(bak) symlink
    173 //
    174 //- Once we have the block device 'node' name(sdb in the above example)
    175 //  use this node to to locate the scsi generic device that represents
    176 //  it by checking the file /sys/block/sdb/device/scsi_generic/sgY
    177 //
    178 //- Once we locate sgY we call the query ioctl on /dev/sgy to switch
    179 //the boot lun to either LUNA or LUNB
    180 int gpt_utils_set_xbl_boot_partition(enum boot_chain chain);
    181 
    182 //Given a vector of partition names as a input and a reference to a map,
    183 //populate the map to indicate which physical disk each of the partitions
    184 //sits on. The key in the map is the path to the block device where the
    185 //partition lies and the value is a vector of strings indicating which of
    186 //the passed in partition names sits on that device.
    187 int gpt_utils_get_partition_map(std::vector<std::string>& partition_list,
    188                 std::map<std::string,std::vector<std::string>>& partition_map);
    189 #ifdef __cplusplus
    190 }
    191 #endif
    192 #endif /* __GPT_UTILS_H__ */
    193