projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
| ac27a0ec | 2 | /* |
| 617ba13b | 3 | * linux/fs/ext4/bitmap.c |
| ac27a0ec DK |
4 | * |
| 5 | * Copyright (C) 1992, 1993, 1994, 1995 | |
| 6 | * Remy Card ([email protected]) | |
| 7 | * Laboratoire MASI - Institut Blaise Pascal | |
| 8 | * Universite Pierre et Marie Curie (Paris VI) | |
| 9 | */ | |
| 10 | ||
| 11 | #include <linux/buffer_head.h> | |
| 3dcf5451 | 12 | #include "ext4.h" |
| ac27a0ec | 13 | |
| f6fb99ca | 14 | unsigned int ext4_count_free(char *bitmap, unsigned int numchars) |
| ac27a0ec | 15 | { |
| 6017b485 | 16 | return numchars * BITS_PER_BYTE - memweight(bitmap, numchars); |
| ac27a0ec DK |
17 | } |
| 18 | ||
| 41a246d1 DW |
19 | int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group, |
| 20 | struct ext4_group_desc *gdp, | |
| 21 | struct buffer_head *bh, int sz) | |
| 22 | { | |
| 23 | __u32 hi; | |
| 24 | __u32 provided, calculated; | |
| 25 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
| 26 | ||
| 9aa5d32b | 27 | if (!ext4_has_metadata_csum(sb)) |
| 41a246d1 DW |
28 | return 1; |
| 29 | ||
| 30 | provided = le16_to_cpu(gdp->bg_inode_bitmap_csum_lo); | |
| 31 | calculated = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)bh->b_data, sz); | |
| 32 | if (sbi->s_desc_size >= EXT4_BG_INODE_BITMAP_CSUM_HI_END) { | |
| 33 | hi = le16_to_cpu(gdp->bg_inode_bitmap_csum_hi); | |
| 34 | provided |= (hi << 16); | |
| 35 | } else | |
| 36 | calculated &= 0xFFFF; | |
| 37 | ||
| 38 | return provided == calculated; | |
| 39 | } | |
| 40 | ||
| 41 | void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group, | |
| 42 | struct ext4_group_desc *gdp, | |
| 43 | struct buffer_head *bh, int sz) | |
| 44 | { | |
| 45 | __u32 csum; | |
| 46 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
| 47 | ||
| 9aa5d32b | 48 | if (!ext4_has_metadata_csum(sb)) |
| 41a246d1 DW |
49 | return; |
| 50 | ||
| 51 | csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)bh->b_data, sz); | |
| 52 | gdp->bg_inode_bitmap_csum_lo = cpu_to_le16(csum & 0xFFFF); | |
| 53 | if (sbi->s_desc_size >= EXT4_BG_INODE_BITMAP_CSUM_HI_END) | |
| 54 | gdp->bg_inode_bitmap_csum_hi = cpu_to_le16(csum >> 16); | |
| 55 | } | |
| fa77dcfa DW |
56 | |
| 57 | int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group, | |
| 58 | struct ext4_group_desc *gdp, | |
| 79f1ba49 | 59 | struct buffer_head *bh) |
| fa77dcfa DW |
60 | { |
| 61 | __u32 hi; | |
| 62 | __u32 provided, calculated; | |
| 63 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
| 79f1ba49 | 64 | int sz = EXT4_CLUSTERS_PER_GROUP(sb) / 8; |
| fa77dcfa | 65 | |
| 9aa5d32b | 66 | if (!ext4_has_metadata_csum(sb)) |
| fa77dcfa DW |
67 | return 1; |
| 68 | ||
| 69 | provided = le16_to_cpu(gdp->bg_block_bitmap_csum_lo); | |
| 70 | calculated = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)bh->b_data, sz); | |
| 71 | if (sbi->s_desc_size >= EXT4_BG_BLOCK_BITMAP_CSUM_HI_END) { | |
| 72 | hi = le16_to_cpu(gdp->bg_block_bitmap_csum_hi); | |
| 73 | provided |= (hi << 16); | |
| 74 | } else | |
| 75 | calculated &= 0xFFFF; | |
| 76 | ||
| 77 | if (provided == calculated) | |
| 78 | return 1; | |
| 79 | ||
| fa77dcfa DW |
80 | return 0; |
| 81 | } | |
| 82 | ||
| 83 | void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group, | |
| 84 | struct ext4_group_desc *gdp, | |
| 79f1ba49 | 85 | struct buffer_head *bh) |
| fa77dcfa | 86 | { |
| 79f1ba49 | 87 | int sz = EXT4_CLUSTERS_PER_GROUP(sb) / 8; |
| fa77dcfa DW |
88 | __u32 csum; |
| 89 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
| 90 | ||
| 9aa5d32b | 91 | if (!ext4_has_metadata_csum(sb)) |
| fa77dcfa DW |
92 | return; |
| 93 | ||
| 94 | csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)bh->b_data, sz); | |
| 95 | gdp->bg_block_bitmap_csum_lo = cpu_to_le16(csum & 0xFFFF); | |
| 96 | if (sbi->s_desc_size >= EXT4_BG_BLOCK_BITMAP_CSUM_HI_END) | |
| 97 | gdp->bg_block_bitmap_csum_hi = cpu_to_le16(csum >> 16); | |
| 98 | } |