| 1 | /*
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| 2 |  * Copyright (c) 2018 Jiri Svoboda
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| 3 |  * Copyright (c) 2012 Frantisek Princ
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| 4 |  * All rights reserved.
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| 5 |  *
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| 6 |  * Redistribution and use in source and binary forms, with or without
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| 7 |  * modification, are permitted provided that the following conditions
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| 8 |  * are met:
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| 9 |  *
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| 10 |  * - Redistributions of source code must retain the above copyright
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| 11 |  *   notice, this list of conditions and the following disclaimer.
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| 12 |  * - Redistributions in binary form must reproduce the above copyright
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| 13 |  *   notice, this list of conditions and the following disclaimer in the
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| 14 |  *   documentation and/or other materials provided with the distribution.
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| 15 |  * - The name of the author may not be used to endorse or promote products
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| 16 |  *   derived from this software without specific prior written permission.
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| 17 |  *
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| 18 |  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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| 19 |  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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| 20 |  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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| 21 |  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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| 22 |  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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| 23 |  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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| 24 |  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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| 25 |  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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| 26 |  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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| 27 |  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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| 28 |  */
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| 29 | 
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| 30 | /** @addtogroup libext4
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| 31 |  * @{
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| 32 |  */
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| 33 | /**
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| 34 |  * @file  balloc.c
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| 35 |  * @brief Physical block allocator.
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| 36 |  */
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| 37 | 
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| 38 | #include <errno.h>
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| 39 | #include <stdbool.h>
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| 40 | #include <stdint.h>
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| 41 | #include "ext4/balloc.h"
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| 42 | #include "ext4/bitmap.h"
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| 43 | #include "ext4/block_group.h"
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| 44 | #include "ext4/filesystem.h"
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| 45 | #include "ext4/inode.h"
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| 46 | #include "ext4/superblock.h"
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| 47 | #include "ext4/types.h"
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| 48 | 
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| 49 | /** Free block.
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| 50 |  *
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| 51 |  * @param inode_ref  Inode, where the block is allocated
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| 52 |  * @param block_addr Absolute block address to free
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| 53 |  *
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| 54 |  * @return Error code
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| 55 |  *
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| 56 |  */
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| 57 | errno_t ext4_balloc_free_block(ext4_inode_ref_t *inode_ref, uint32_t block_addr)
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| 58 | {
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| 59 |         ext4_filesystem_t *fs = inode_ref->fs;
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| 60 |         ext4_superblock_t *sb = fs->superblock;
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| 61 | 
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| 62 |         /* Compute indexes */
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| 63 |         uint32_t block_group = ext4_filesystem_blockaddr2group(sb, block_addr);
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| 64 |         uint32_t index_in_group =
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| 65 |             ext4_filesystem_blockaddr2_index_in_group(sb, block_addr);
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| 66 | 
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| 67 |         /* Load block group reference */
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| 68 |         ext4_block_group_ref_t *bg_ref;
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| 69 |         errno_t rc = ext4_filesystem_get_block_group_ref(fs, block_group, &bg_ref);
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| 70 |         if (rc != EOK)
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| 71 |                 return rc;
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| 72 | 
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| 73 |         /* Load block with bitmap */
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| 74 |         uint32_t bitmap_block_addr =
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| 75 |             ext4_block_group_get_block_bitmap(bg_ref->block_group, sb);
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| 76 |         block_t *bitmap_block;
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| 77 |         rc = block_get(&bitmap_block, fs->device, bitmap_block_addr, 0);
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| 78 |         if (rc != EOK) {
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| 79 |                 ext4_filesystem_put_block_group_ref(bg_ref);
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| 80 |                 return rc;
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| 81 |         }
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| 82 | 
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| 83 |         /* Modify bitmap */
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| 84 |         ext4_bitmap_free_bit(bitmap_block->data, index_in_group);
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| 85 |         bitmap_block->dirty = true;
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| 86 | 
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| 87 |         /* Release block with bitmap */
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| 88 |         rc = block_put(bitmap_block);
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| 89 |         if (rc != EOK) {
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| 90 |                 /* Error in saving bitmap */
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| 91 |                 ext4_filesystem_put_block_group_ref(bg_ref);
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| 92 |                 return rc;
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| 93 |         }
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| 94 | 
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| 95 |         uint32_t block_size = ext4_superblock_get_block_size(sb);
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| 96 | 
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| 97 |         /* Update superblock free blocks count */
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| 98 |         uint32_t sb_free_blocks =
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| 99 |             ext4_superblock_get_free_blocks_count(sb);
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| 100 |         sb_free_blocks++;
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| 101 |         ext4_superblock_set_free_blocks_count(sb, sb_free_blocks);
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| 102 | 
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| 103 |         /* Update inode blocks count */
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| 104 |         uint64_t ino_blocks =
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| 105 |             ext4_inode_get_blocks_count(sb, inode_ref->inode);
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| 106 |         ino_blocks -= block_size / EXT4_INODE_BLOCK_SIZE;
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| 107 |         ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
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| 108 |         inode_ref->dirty = true;
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| 109 | 
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| 110 |         /* Update block group free blocks count */
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| 111 |         uint32_t free_blocks =
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| 112 |             ext4_block_group_get_free_blocks_count(bg_ref->block_group, sb);
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| 113 |         free_blocks++;
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| 114 |         ext4_block_group_set_free_blocks_count(bg_ref->block_group,
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| 115 |             sb, free_blocks);
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| 116 |         bg_ref->dirty = true;
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| 117 | 
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| 118 |         /* Release block group reference */
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| 119 |         return ext4_filesystem_put_block_group_ref(bg_ref);
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| 120 | }
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| 121 | 
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| 122 | static errno_t ext4_balloc_free_blocks_internal(ext4_inode_ref_t *inode_ref,
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| 123 |     uint32_t first, uint32_t count)
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| 124 | {
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| 125 |         ext4_filesystem_t *fs = inode_ref->fs;
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| 126 |         ext4_superblock_t *sb = fs->superblock;
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| 127 | 
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| 128 |         /* Compute indexes */
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| 129 |         uint32_t block_group_first = ext4_filesystem_blockaddr2group(sb,
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| 130 |             first);
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| 131 |         uint32_t block_group_last = ext4_filesystem_blockaddr2group(sb,
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| 132 |             first + count - 1);
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| 133 | 
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| 134 |         assert(block_group_first == block_group_last);
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| 135 | 
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| 136 |         /* Load block group reference */
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| 137 |         ext4_block_group_ref_t *bg_ref;
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| 138 |         errno_t rc = ext4_filesystem_get_block_group_ref(fs, block_group_first, &bg_ref);
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| 139 |         if (rc != EOK)
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| 140 |                 return rc;
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| 141 | 
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| 142 |         uint32_t index_in_group_first =
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| 143 |             ext4_filesystem_blockaddr2_index_in_group(sb, first);
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| 144 | 
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| 145 |         /* Load block with bitmap */
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| 146 |         uint32_t bitmap_block_addr =
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| 147 |             ext4_block_group_get_block_bitmap(bg_ref->block_group, sb);
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| 148 | 
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| 149 |         block_t *bitmap_block;
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| 150 |         rc = block_get(&bitmap_block, fs->device, bitmap_block_addr, 0);
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| 151 |         if (rc != EOK) {
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| 152 |                 ext4_filesystem_put_block_group_ref(bg_ref);
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| 153 |                 return rc;
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| 154 |         }
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| 155 | 
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| 156 |         /* Modify bitmap */
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| 157 |         ext4_bitmap_free_bits(bitmap_block->data, index_in_group_first, count);
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| 158 |         bitmap_block->dirty = true;
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| 159 | 
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| 160 |         /* Release block with bitmap */
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| 161 |         rc = block_put(bitmap_block);
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| 162 |         if (rc != EOK) {
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| 163 |                 /* Error in saving bitmap */
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| 164 |                 ext4_filesystem_put_block_group_ref(bg_ref);
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| 165 |                 return rc;
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| 166 |         }
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| 167 | 
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| 168 |         uint32_t block_size = ext4_superblock_get_block_size(sb);
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| 169 | 
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| 170 |         /* Update superblock free blocks count */
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| 171 |         uint32_t sb_free_blocks =
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| 172 |             ext4_superblock_get_free_blocks_count(sb);
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| 173 |         sb_free_blocks += count;
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| 174 |         ext4_superblock_set_free_blocks_count(sb, sb_free_blocks);
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| 175 | 
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| 176 |         /* Update inode blocks count */
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| 177 |         uint64_t ino_blocks =
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| 178 |             ext4_inode_get_blocks_count(sb, inode_ref->inode);
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| 179 |         ino_blocks -= count * (block_size / EXT4_INODE_BLOCK_SIZE);
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| 180 |         ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
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| 181 |         inode_ref->dirty = true;
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| 182 | 
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| 183 |         /* Update block group free blocks count */
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| 184 |         uint32_t free_blocks =
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| 185 |             ext4_block_group_get_free_blocks_count(bg_ref->block_group, sb);
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| 186 |         free_blocks += count;
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| 187 |         ext4_block_group_set_free_blocks_count(bg_ref->block_group,
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| 188 |             sb, free_blocks);
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| 189 |         bg_ref->dirty = true;
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| 190 | 
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| 191 |         /* Release block group reference */
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| 192 |         return ext4_filesystem_put_block_group_ref(bg_ref);
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| 193 | }
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| 194 | 
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| 195 | /** Free continuous set of blocks.
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| 196 |  *
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| 197 |  * @param inode_ref Inode, where the blocks are allocated
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| 198 |  * @param first     First block to release
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| 199 |  * @param count     Number of blocks to release
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| 200 |  *
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| 201 |  */
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| 202 | errno_t ext4_balloc_free_blocks(ext4_inode_ref_t *inode_ref,
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| 203 |     uint32_t first, uint32_t count)
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| 204 | {
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| 205 |         errno_t r;
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| 206 |         uint32_t gid;
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| 207 |         uint64_t limit;
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| 208 |         ext4_filesystem_t *fs = inode_ref->fs;
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| 209 |         ext4_superblock_t *sb = fs->superblock;
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| 210 | 
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| 211 |         while (count) {
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| 212 |                 gid = ext4_filesystem_blockaddr2group(sb, first);
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| 213 |                 limit = ext4_filesystem_index_in_group2blockaddr(sb, 0,
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| 214 |                     gid + 1);
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| 215 | 
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| 216 |                 if ((first + count) >= limit) {
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| 217 |                         /*
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| 218 |                          * This extent spans over 2 or more block groups,
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| 219 |                          * we'll break it into smaller parts.
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| 220 |                          */
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| 221 |                         uint32_t s = limit - first;
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| 222 | 
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| 223 |                         r = ext4_balloc_free_blocks_internal(inode_ref,
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| 224 |                             first, s);
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| 225 |                         if (r != EOK)
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| 226 |                                 return r;
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| 227 | 
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| 228 |                         first = limit;
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| 229 |                         count -= s;
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| 230 |                 } else {
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| 231 |                         return ext4_balloc_free_blocks_internal(inode_ref,
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| 232 |                             first, count);
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| 233 |                 }
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| 234 |         }
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| 235 | 
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| 236 |         return EOK;
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| 237 | }
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| 238 | 
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| 239 | /** Compute first block for data in block group.
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| 240 |  *
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| 241 |  * @param sb   Pointer to superblock
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| 242 |  * @param bg   Pointer to block group
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| 243 |  * @param bgid Index of block group
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| 244 |  *
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| 245 |  * @return Absolute block index of first block
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| 246 |  *
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| 247 |  */
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| 248 | uint32_t ext4_balloc_get_first_data_block_in_group(ext4_superblock_t *sb,
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| 249 |     ext4_block_group_ref_t *bg_ref)
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| 250 | {
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| 251 |         uint32_t r;
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| 252 |         uint64_t itable = ext4_block_group_get_inode_table_first_block(
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| 253 |             bg_ref->block_group, sb);
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| 254 |         uint32_t itable_sz = ext4_filesystem_bg_get_itable_size(sb,
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| 255 |             bg_ref->index);
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| 256 | 
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| 257 |         if (!ext4_superblock_has_feature_incompatible(sb,
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| 258 |             EXT4_FEATURE_INCOMPAT_FLEX_BG)) {
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| 259 |                 /*
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| 260 |                  * If we are not using FLEX_BG, the first data block
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| 261 |                  * is always after the inode table.
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| 262 |                  */
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| 263 |                 return itable + itable_sz;
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| 264 |         }
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| 265 | 
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| 266 |         uint32_t flex_group_size = ext4_superblock_get_flex_group_size(sb);
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| 267 |         if ((bg_ref->index % flex_group_size) == 0) {
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| 268 |                 /* This is the base group */
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| 269 |                 uint32_t i;
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| 270 | 
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| 271 |                 r = itable + itable_sz;
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| 272 | 
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| 273 |                 uint32_t total_groups = ext4_superblock_get_block_group_count(sb);
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| 274 |                 for (i = bg_ref->index + 1;
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| 275 |                     i < min(total_groups, bg_ref->index + flex_group_size); ++i) {
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| 276 |                         r += ext4_filesystem_bg_get_itable_size(sb, i);
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| 277 |                 }
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| 278 | 
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| 279 |                 return r;
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| 280 |         }
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| 281 | 
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| 282 |         uint64_t base_addr = ext4_filesystem_index_in_group2blockaddr(sb, 0,
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| 283 |             bg_ref->index);
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| 284 |         uint32_t reserved = ext4_filesystem_bg_get_backup_blocks(bg_ref);
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| 285 | 
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| 286 |         return base_addr + reserved;
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| 287 | }
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| 288 | 
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| 289 | /** Compute 'goal' for allocation algorithm.
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| 290 |  *
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| 291 |  * @param inode_ref Reference to inode, to allocate block for
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| 292 |  *
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| 293 |  * @return Goal block number
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| 294 |  *
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| 295 |  */
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| 296 | static errno_t ext4_balloc_find_goal(ext4_inode_ref_t *inode_ref, uint32_t *goal)
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| 297 | {
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| 298 |         *goal = 0;
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| 299 |         ext4_superblock_t *sb = inode_ref->fs->superblock;
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| 300 | 
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| 301 |         uint64_t inode_size = ext4_inode_get_size(sb, inode_ref->inode);
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| 302 |         uint32_t block_size = ext4_superblock_get_block_size(sb);
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| 303 |         uint32_t inode_block_count = inode_size / block_size;
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| 304 | 
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| 305 |         if (inode_size % block_size != 0)
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| 306 |                 inode_block_count++;
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| 307 | 
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| 308 |         /* If inode has some blocks, get last block address + 1 */
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| 309 |         if (inode_block_count > 0) {
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| 310 |                 errno_t rc = ext4_filesystem_get_inode_data_block_index(inode_ref,
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| 311 |                     inode_block_count - 1, goal);
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| 312 |                 if (rc != EOK)
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| 313 |                         return rc;
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| 314 | 
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| 315 |                 if (goal != 0) {
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| 316 |                         (*goal)++;
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| 317 |                         return EOK;
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| 318 |                 }
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| 319 |                 /* If goal == 0, sparse file -> continue */
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| 320 |         }
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| 321 | 
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| 322 |         /* Identify block group of inode */
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| 323 |         uint32_t inodes_per_group = ext4_superblock_get_inodes_per_group(sb);
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| 324 |         uint32_t block_group = (inode_ref->index - 1) / inodes_per_group;
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| 325 | 
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| 326 |         /* Load block group reference */
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| 327 |         ext4_block_group_ref_t *bg_ref;
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| 328 |         errno_t rc = ext4_filesystem_get_block_group_ref(inode_ref->fs,
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| 329 |             block_group, &bg_ref);
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| 330 |         if (rc != EOK)
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| 331 |                 return rc;
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| 332 | 
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| 333 |         *goal = ext4_balloc_get_first_data_block_in_group(sb, bg_ref);
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| 334 | 
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| 335 |         return ext4_filesystem_put_block_group_ref(bg_ref);
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| 336 | }
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| 337 | 
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| 338 | /** Data block allocation algorithm.
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| 339 |  *
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| 340 |  * @param inode_ref Inode to allocate block for
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| 341 |  * @param fblock    Allocated block address
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| 342 |  *
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| 343 |  * @return Error code
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| 344 |  *
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| 345 |  */
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| 346 | errno_t ext4_balloc_alloc_block(ext4_inode_ref_t *inode_ref, uint32_t *fblock)
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| 347 | {
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| 348 |         uint32_t allocated_block = 0;
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| 349 | 
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| 350 |         uint32_t bitmap_block_addr;
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| 351 |         block_t *bitmap_block;
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| 352 |         uint32_t rel_block_idx = 0;
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| 353 |         uint32_t free_blocks;
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| 354 |         uint32_t goal;
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| 355 |         uint32_t block_size;
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| 356 | 
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| 357 |         /* Find GOAL */
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| 358 |         errno_t rc = ext4_balloc_find_goal(inode_ref, &goal);
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| 359 |         if (rc != EOK)
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| 360 |                 return rc;
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| 361 | 
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| 362 |         ext4_superblock_t *sb = inode_ref->fs->superblock;
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| 363 | 
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| 364 |         /* Load block group number for goal and relative index */
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| 365 |         uint32_t block_group = ext4_filesystem_blockaddr2group(sb, goal);
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| 366 |         uint32_t index_in_group =
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| 367 |             ext4_filesystem_blockaddr2_index_in_group(sb, goal);
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| 368 | 
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| 369 |         /* Load block group reference */
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| 370 |         ext4_block_group_ref_t *bg_ref;
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| 371 |         rc = ext4_filesystem_get_block_group_ref(inode_ref->fs,
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| 372 |             block_group, &bg_ref);
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| 373 |         if (rc != EOK)
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| 374 |                 return rc;
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| 375 | 
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| 376 |         free_blocks =
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| 377 |             ext4_block_group_get_free_blocks_count(bg_ref->block_group, sb);
 | 
|---|
| 378 |         if (free_blocks == 0) {
 | 
|---|
| 379 |                 /* This group has no free blocks */
 | 
|---|
| 380 |                 goto goal_failed;
 | 
|---|
| 381 |         }
 | 
|---|
| 382 | 
 | 
|---|
| 383 |         /* Compute indexes */
 | 
|---|
| 384 |         uint32_t first_in_group =
 | 
|---|
| 385 |             ext4_balloc_get_first_data_block_in_group(sb, bg_ref);
 | 
|---|
| 386 | 
 | 
|---|
| 387 |         uint32_t first_in_group_index =
 | 
|---|
| 388 |             ext4_filesystem_blockaddr2_index_in_group(sb, first_in_group);
 | 
|---|
| 389 | 
 | 
|---|
| 390 |         if (index_in_group < first_in_group_index)
 | 
|---|
| 391 |                 index_in_group = first_in_group_index;
 | 
|---|
| 392 | 
 | 
|---|
| 393 |         /* Load block with bitmap */
 | 
|---|
| 394 |         bitmap_block_addr =
 | 
|---|
| 395 |             ext4_block_group_get_block_bitmap(bg_ref->block_group, sb);
 | 
|---|
| 396 | 
 | 
|---|
| 397 |         rc = block_get(&bitmap_block, inode_ref->fs->device,
 | 
|---|
| 398 |             bitmap_block_addr, BLOCK_FLAGS_NONE);
 | 
|---|
| 399 |         if (rc != EOK) {
 | 
|---|
| 400 |                 ext4_filesystem_put_block_group_ref(bg_ref);
 | 
|---|
| 401 |                 return rc;
 | 
|---|
| 402 |         }
 | 
|---|
| 403 | 
 | 
|---|
| 404 |         /* Check if goal is free */
 | 
|---|
| 405 |         if (ext4_bitmap_is_free_bit(bitmap_block->data, index_in_group)) {
 | 
|---|
| 406 |                 ext4_bitmap_set_bit(bitmap_block->data, index_in_group);
 | 
|---|
| 407 |                 bitmap_block->dirty = true;
 | 
|---|
| 408 |                 rc = block_put(bitmap_block);
 | 
|---|
| 409 |                 if (rc != EOK) {
 | 
|---|
| 410 |                         ext4_filesystem_put_block_group_ref(bg_ref);
 | 
|---|
| 411 |                         return rc;
 | 
|---|
| 412 |                 }
 | 
|---|
| 413 | 
 | 
|---|
| 414 |                 allocated_block =
 | 
|---|
| 415 |                     ext4_filesystem_index_in_group2blockaddr(sb, index_in_group,
 | 
|---|
| 416 |                     block_group);
 | 
|---|
| 417 | 
 | 
|---|
| 418 |                 goto success;
 | 
|---|
| 419 |         }
 | 
|---|
| 420 | 
 | 
|---|
| 421 |         uint32_t blocks_in_group =
 | 
|---|
| 422 |             ext4_superblock_get_blocks_in_group(sb, block_group);
 | 
|---|
| 423 | 
 | 
|---|
| 424 |         uint32_t end_idx = (index_in_group + 63) & ~63;
 | 
|---|
| 425 |         if (end_idx > blocks_in_group)
 | 
|---|
| 426 |                 end_idx = blocks_in_group;
 | 
|---|
| 427 | 
 | 
|---|
| 428 |         /* Try to find free block near to goal */
 | 
|---|
| 429 |         for (uint32_t tmp_idx = index_in_group + 1; tmp_idx < end_idx;
 | 
|---|
| 430 |             ++tmp_idx) {
 | 
|---|
| 431 |                 if (ext4_bitmap_is_free_bit(bitmap_block->data, tmp_idx)) {
 | 
|---|
| 432 |                         ext4_bitmap_set_bit(bitmap_block->data, tmp_idx);
 | 
|---|
| 433 |                         bitmap_block->dirty = true;
 | 
|---|
| 434 |                         rc = block_put(bitmap_block);
 | 
|---|
| 435 |                         if (rc != EOK)
 | 
|---|
| 436 |                                 return rc;
 | 
|---|
| 437 | 
 | 
|---|
| 438 |                         allocated_block =
 | 
|---|
| 439 |                             ext4_filesystem_index_in_group2blockaddr(sb, tmp_idx,
 | 
|---|
| 440 |                             block_group);
 | 
|---|
| 441 | 
 | 
|---|
| 442 |                         goto success;
 | 
|---|
| 443 |                 }
 | 
|---|
| 444 |         }
 | 
|---|
| 445 | 
 | 
|---|
| 446 |         /* Find free BYTE in bitmap */
 | 
|---|
| 447 |         rc = ext4_bitmap_find_free_byte_and_set_bit(bitmap_block->data,
 | 
|---|
| 448 |             index_in_group, &rel_block_idx, blocks_in_group);
 | 
|---|
| 449 |         if (rc == EOK) {
 | 
|---|
| 450 |                 bitmap_block->dirty = true;
 | 
|---|
| 451 |                 rc = block_put(bitmap_block);
 | 
|---|
| 452 |                 if (rc != EOK)
 | 
|---|
| 453 |                         return rc;
 | 
|---|
| 454 | 
 | 
|---|
| 455 |                 allocated_block =
 | 
|---|
| 456 |                     ext4_filesystem_index_in_group2blockaddr(sb, rel_block_idx,
 | 
|---|
| 457 |                     block_group);
 | 
|---|
| 458 | 
 | 
|---|
| 459 |                 goto success;
 | 
|---|
| 460 |         }
 | 
|---|
| 461 | 
 | 
|---|
| 462 |         /* Find free bit in bitmap */
 | 
|---|
| 463 |         rc = ext4_bitmap_find_free_bit_and_set(bitmap_block->data,
 | 
|---|
| 464 |             index_in_group, &rel_block_idx, blocks_in_group);
 | 
|---|
| 465 |         if (rc == EOK) {
 | 
|---|
| 466 |                 bitmap_block->dirty = true;
 | 
|---|
| 467 |                 rc = block_put(bitmap_block);
 | 
|---|
| 468 |                 if (rc != EOK)
 | 
|---|
| 469 |                         return rc;
 | 
|---|
| 470 | 
 | 
|---|
| 471 |                 allocated_block =
 | 
|---|
| 472 |                     ext4_filesystem_index_in_group2blockaddr(sb, rel_block_idx,
 | 
|---|
| 473 |                     block_group);
 | 
|---|
| 474 | 
 | 
|---|
| 475 |                 goto success;
 | 
|---|
| 476 |         }
 | 
|---|
| 477 | 
 | 
|---|
| 478 |         /* No free block found yet */
 | 
|---|
| 479 |         rc = block_put(bitmap_block);
 | 
|---|
| 480 |         if (rc != EOK) {
 | 
|---|
| 481 |                 ext4_filesystem_put_block_group_ref(bg_ref);
 | 
|---|
| 482 |                 return rc;
 | 
|---|
| 483 |         }
 | 
|---|
| 484 | 
 | 
|---|
| 485 | goal_failed:
 | 
|---|
| 486 | 
 | 
|---|
| 487 |         rc = ext4_filesystem_put_block_group_ref(bg_ref);
 | 
|---|
| 488 |         if (rc != EOK)
 | 
|---|
| 489 |                 return rc;
 | 
|---|
| 490 | 
 | 
|---|
| 491 |         /* Try other block groups */
 | 
|---|
| 492 |         uint32_t block_group_count = ext4_superblock_get_block_group_count(sb);
 | 
|---|
| 493 | 
 | 
|---|
| 494 |         uint32_t bgid = (block_group + 1) % block_group_count;
 | 
|---|
| 495 |         uint32_t count = block_group_count;
 | 
|---|
| 496 | 
 | 
|---|
| 497 |         while (count > 0) {
 | 
|---|
| 498 |                 rc = ext4_filesystem_get_block_group_ref(inode_ref->fs, bgid,
 | 
|---|
| 499 |                     &bg_ref);
 | 
|---|
| 500 |                 if (rc != EOK)
 | 
|---|
| 501 |                         return rc;
 | 
|---|
| 502 | 
 | 
|---|
| 503 |                 free_blocks =
 | 
|---|
| 504 |                     ext4_block_group_get_free_blocks_count(bg_ref->block_group, sb);
 | 
|---|
| 505 |                 if (free_blocks == 0) {
 | 
|---|
| 506 |                         /* This group has no free blocks */
 | 
|---|
| 507 |                         goto next_group;
 | 
|---|
| 508 |                 }
 | 
|---|
| 509 | 
 | 
|---|
| 510 |                 /* Load block with bitmap */
 | 
|---|
| 511 |                 bitmap_block_addr =
 | 
|---|
| 512 |                     ext4_block_group_get_block_bitmap(bg_ref->block_group, sb);
 | 
|---|
| 513 | 
 | 
|---|
| 514 |                 rc = block_get(&bitmap_block, inode_ref->fs->device,
 | 
|---|
| 515 |                     bitmap_block_addr, 0);
 | 
|---|
| 516 |                 if (rc != EOK) {
 | 
|---|
| 517 |                         ext4_filesystem_put_block_group_ref(bg_ref);
 | 
|---|
| 518 |                         return rc;
 | 
|---|
| 519 |                 }
 | 
|---|
| 520 | 
 | 
|---|
| 521 |                 /* Compute indexes */
 | 
|---|
| 522 |                 first_in_group =
 | 
|---|
| 523 |                     ext4_balloc_get_first_data_block_in_group(sb, bg_ref);
 | 
|---|
| 524 |                 index_in_group =
 | 
|---|
| 525 |                     ext4_filesystem_blockaddr2_index_in_group(sb, first_in_group);
 | 
|---|
| 526 |                 blocks_in_group = ext4_superblock_get_blocks_in_group(sb, bgid);
 | 
|---|
| 527 | 
 | 
|---|
| 528 |                 first_in_group_index =
 | 
|---|
| 529 |                     ext4_filesystem_blockaddr2_index_in_group(sb, first_in_group);
 | 
|---|
| 530 | 
 | 
|---|
| 531 |                 if (index_in_group < first_in_group_index)
 | 
|---|
| 532 |                         index_in_group = first_in_group_index;
 | 
|---|
| 533 | 
 | 
|---|
| 534 |                 /* Try to find free byte in bitmap */
 | 
|---|
| 535 |                 rc = ext4_bitmap_find_free_byte_and_set_bit(bitmap_block->data,
 | 
|---|
| 536 |                     index_in_group, &rel_block_idx, blocks_in_group);
 | 
|---|
| 537 |                 if (rc == EOK) {
 | 
|---|
| 538 |                         bitmap_block->dirty = true;
 | 
|---|
| 539 |                         rc = block_put(bitmap_block);
 | 
|---|
| 540 |                         if (rc != EOK) {
 | 
|---|
| 541 |                                 ext4_filesystem_put_block_group_ref(bg_ref);
 | 
|---|
| 542 |                                 return rc;
 | 
|---|
| 543 |                         }
 | 
|---|
| 544 | 
 | 
|---|
| 545 |                         allocated_block =
 | 
|---|
| 546 |                             ext4_filesystem_index_in_group2blockaddr(sb, rel_block_idx,
 | 
|---|
| 547 |                             bgid);
 | 
|---|
| 548 | 
 | 
|---|
| 549 |                         goto success;
 | 
|---|
| 550 |                 }
 | 
|---|
| 551 | 
 | 
|---|
| 552 |                 /* Try to find free bit in bitmap */
 | 
|---|
| 553 |                 rc = ext4_bitmap_find_free_bit_and_set(bitmap_block->data,
 | 
|---|
| 554 |                     index_in_group, &rel_block_idx, blocks_in_group);
 | 
|---|
| 555 |                 if (rc == EOK) {
 | 
|---|
| 556 |                         bitmap_block->dirty = true;
 | 
|---|
| 557 |                         rc = block_put(bitmap_block);
 | 
|---|
| 558 |                         if (rc != EOK) {
 | 
|---|
| 559 |                                 ext4_filesystem_put_block_group_ref(bg_ref);
 | 
|---|
| 560 |                                 return rc;
 | 
|---|
| 561 |                         }
 | 
|---|
| 562 | 
 | 
|---|
| 563 |                         allocated_block =
 | 
|---|
| 564 |                             ext4_filesystem_index_in_group2blockaddr(sb, rel_block_idx,
 | 
|---|
| 565 |                             bgid);
 | 
|---|
| 566 | 
 | 
|---|
| 567 |                         goto success;
 | 
|---|
| 568 |                 }
 | 
|---|
| 569 | 
 | 
|---|
| 570 |                 rc = block_put(bitmap_block);
 | 
|---|
| 571 |                 if (rc != EOK) {
 | 
|---|
| 572 |                         ext4_filesystem_put_block_group_ref(bg_ref);
 | 
|---|
| 573 |                         return rc;
 | 
|---|
| 574 |                 }
 | 
|---|
| 575 | 
 | 
|---|
| 576 |         next_group:
 | 
|---|
| 577 |                 rc = ext4_filesystem_put_block_group_ref(bg_ref);
 | 
|---|
| 578 |                 if (rc != EOK)
 | 
|---|
| 579 |                         return rc;
 | 
|---|
| 580 | 
 | 
|---|
| 581 |                 /* Goto next group */
 | 
|---|
| 582 |                 bgid = (bgid + 1) % block_group_count;
 | 
|---|
| 583 |                 count--;
 | 
|---|
| 584 |         }
 | 
|---|
| 585 | 
 | 
|---|
| 586 |         return ENOSPC;
 | 
|---|
| 587 | 
 | 
|---|
| 588 | success:
 | 
|---|
| 589 |         block_size = ext4_superblock_get_block_size(sb);
 | 
|---|
| 590 | 
 | 
|---|
| 591 |         /* Update superblock free blocks count */
 | 
|---|
| 592 |         uint32_t sb_free_blocks = ext4_superblock_get_free_blocks_count(sb);
 | 
|---|
| 593 |         sb_free_blocks--;
 | 
|---|
| 594 |         ext4_superblock_set_free_blocks_count(sb, sb_free_blocks);
 | 
|---|
| 595 | 
 | 
|---|
| 596 |         /* Update inode blocks (different block size!) count */
 | 
|---|
| 597 |         uint64_t ino_blocks =
 | 
|---|
| 598 |             ext4_inode_get_blocks_count(sb, inode_ref->inode);
 | 
|---|
| 599 |         ino_blocks += block_size / EXT4_INODE_BLOCK_SIZE;
 | 
|---|
| 600 |         ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
 | 
|---|
| 601 |         inode_ref->dirty = true;
 | 
|---|
| 602 | 
 | 
|---|
| 603 |         /* Update block group free blocks count */
 | 
|---|
| 604 |         uint32_t bg_free_blocks =
 | 
|---|
| 605 |             ext4_block_group_get_free_blocks_count(bg_ref->block_group, sb);
 | 
|---|
| 606 |         bg_free_blocks--;
 | 
|---|
| 607 |         ext4_block_group_set_free_blocks_count(bg_ref->block_group, sb,
 | 
|---|
| 608 |             bg_free_blocks);
 | 
|---|
| 609 |         bg_ref->dirty = true;
 | 
|---|
| 610 | 
 | 
|---|
| 611 |         rc = ext4_filesystem_put_block_group_ref(bg_ref);
 | 
|---|
| 612 | 
 | 
|---|
| 613 |         *fblock = allocated_block;
 | 
|---|
| 614 |         return rc;
 | 
|---|
| 615 | }
 | 
|---|
| 616 | 
 | 
|---|
| 617 | /** Try to allocate concrete block.
 | 
|---|
| 618 |  *
 | 
|---|
| 619 |  * @param inode_ref Inode to allocate block for
 | 
|---|
| 620 |  * @param fblock    Block address to allocate
 | 
|---|
| 621 |  * @param free      Output value - if target block is free
 | 
|---|
| 622 |  *
 | 
|---|
| 623 |  * @return Error code
 | 
|---|
| 624 |  *
 | 
|---|
| 625 |  */
 | 
|---|
| 626 | errno_t ext4_balloc_try_alloc_block(ext4_inode_ref_t *inode_ref, uint32_t fblock,
 | 
|---|
| 627 |     bool *free)
 | 
|---|
| 628 | {
 | 
|---|
| 629 |         errno_t rc;
 | 
|---|
| 630 | 
 | 
|---|
| 631 |         ext4_filesystem_t *fs = inode_ref->fs;
 | 
|---|
| 632 |         ext4_superblock_t *sb = fs->superblock;
 | 
|---|
| 633 | 
 | 
|---|
| 634 |         /* Compute indexes */
 | 
|---|
| 635 |         uint32_t block_group = ext4_filesystem_blockaddr2group(sb, fblock);
 | 
|---|
| 636 |         uint32_t index_in_group =
 | 
|---|
| 637 |             ext4_filesystem_blockaddr2_index_in_group(sb, fblock);
 | 
|---|
| 638 | 
 | 
|---|
| 639 |         /* Load block group reference */
 | 
|---|
| 640 |         ext4_block_group_ref_t *bg_ref;
 | 
|---|
| 641 |         rc = ext4_filesystem_get_block_group_ref(fs, block_group, &bg_ref);
 | 
|---|
| 642 |         if (rc != EOK)
 | 
|---|
| 643 |                 return rc;
 | 
|---|
| 644 | 
 | 
|---|
| 645 |         /* Load block with bitmap */
 | 
|---|
| 646 |         uint32_t bitmap_block_addr =
 | 
|---|
| 647 |             ext4_block_group_get_block_bitmap(bg_ref->block_group, sb);
 | 
|---|
| 648 |         block_t *bitmap_block;
 | 
|---|
| 649 |         rc = block_get(&bitmap_block, fs->device, bitmap_block_addr, 0);
 | 
|---|
| 650 |         if (rc != EOK) {
 | 
|---|
| 651 |                 ext4_filesystem_put_block_group_ref(bg_ref);
 | 
|---|
| 652 |                 return rc;
 | 
|---|
| 653 |         }
 | 
|---|
| 654 | 
 | 
|---|
| 655 |         /* Check if block is free */
 | 
|---|
| 656 |         *free = ext4_bitmap_is_free_bit(bitmap_block->data, index_in_group);
 | 
|---|
| 657 | 
 | 
|---|
| 658 |         /* Allocate block if possible */
 | 
|---|
| 659 |         if (*free) {
 | 
|---|
| 660 |                 ext4_bitmap_set_bit(bitmap_block->data, index_in_group);
 | 
|---|
| 661 |                 bitmap_block->dirty = true;
 | 
|---|
| 662 |         }
 | 
|---|
| 663 | 
 | 
|---|
| 664 |         /* Release block with bitmap */
 | 
|---|
| 665 |         rc = block_put(bitmap_block);
 | 
|---|
| 666 |         if (rc != EOK) {
 | 
|---|
| 667 |                 /* Error in saving bitmap */
 | 
|---|
| 668 |                 ext4_filesystem_put_block_group_ref(bg_ref);
 | 
|---|
| 669 |                 return rc;
 | 
|---|
| 670 |         }
 | 
|---|
| 671 | 
 | 
|---|
| 672 |         /* If block is not free, return */
 | 
|---|
| 673 |         if (!(*free))
 | 
|---|
| 674 |                 goto terminate;
 | 
|---|
| 675 | 
 | 
|---|
| 676 |         uint32_t block_size = ext4_superblock_get_block_size(sb);
 | 
|---|
| 677 | 
 | 
|---|
| 678 |         /* Update superblock free blocks count */
 | 
|---|
| 679 |         uint32_t sb_free_blocks = ext4_superblock_get_free_blocks_count(sb);
 | 
|---|
| 680 |         sb_free_blocks--;
 | 
|---|
| 681 |         ext4_superblock_set_free_blocks_count(sb, sb_free_blocks);
 | 
|---|
| 682 | 
 | 
|---|
| 683 |         /* Update inode blocks count */
 | 
|---|
| 684 |         uint64_t ino_blocks =
 | 
|---|
| 685 |             ext4_inode_get_blocks_count(sb, inode_ref->inode);
 | 
|---|
| 686 |         ino_blocks += block_size / EXT4_INODE_BLOCK_SIZE;
 | 
|---|
| 687 |         ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
 | 
|---|
| 688 |         inode_ref->dirty = true;
 | 
|---|
| 689 | 
 | 
|---|
| 690 |         /* Update block group free blocks count */
 | 
|---|
| 691 |         uint32_t free_blocks =
 | 
|---|
| 692 |             ext4_block_group_get_free_blocks_count(bg_ref->block_group, sb);
 | 
|---|
| 693 |         free_blocks--;
 | 
|---|
| 694 |         ext4_block_group_set_free_blocks_count(bg_ref->block_group,
 | 
|---|
| 695 |             sb, free_blocks);
 | 
|---|
| 696 |         bg_ref->dirty = true;
 | 
|---|
| 697 | 
 | 
|---|
| 698 | terminate:
 | 
|---|
| 699 |         return ext4_filesystem_put_block_group_ref(bg_ref);
 | 
|---|
| 700 | }
 | 
|---|
| 701 | 
 | 
|---|
| 702 | /**
 | 
|---|
| 703 |  * @}
 | 
|---|
| 704 |  */
 | 
|---|