1b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0
2ac27a0ecSDave Kleikamp /*
3617ba13bSMingming Cao * linux/fs/ext4/bitmap.c
4ac27a0ecSDave Kleikamp *
5ac27a0ecSDave Kleikamp * Copyright (C) 1992, 1993, 1994, 1995
6ac27a0ecSDave Kleikamp * Remy Card (card@masi.ibp.fr)
7ac27a0ecSDave Kleikamp * Laboratoire MASI - Institut Blaise Pascal
8ac27a0ecSDave Kleikamp * Universite Pierre et Marie Curie (Paris VI)
9ac27a0ecSDave Kleikamp */
10ac27a0ecSDave Kleikamp
11ac27a0ecSDave Kleikamp #include <linux/buffer_head.h>
123dcf5451SChristoph Hellwig #include "ext4.h"
13ac27a0ecSDave Kleikamp
ext4_count_free(char * bitmap,unsigned int numchars)14f6fb99caSTheodore Ts'o unsigned int ext4_count_free(char *bitmap, unsigned int numchars)
15ac27a0ecSDave Kleikamp {
166017b485SAkinobu Mita return numchars * BITS_PER_BYTE - memweight(bitmap, numchars);
17ac27a0ecSDave Kleikamp }
18ac27a0ecSDave Kleikamp
ext4_inode_bitmap_csum_verify(struct super_block * sb,struct ext4_group_desc * gdp,struct buffer_head * bh,int sz)19b83acc77SKemeng Shi int ext4_inode_bitmap_csum_verify(struct super_block *sb,
2041a246d1SDarrick J. Wong struct ext4_group_desc *gdp,
2141a246d1SDarrick J. Wong struct buffer_head *bh, int sz)
2241a246d1SDarrick J. Wong {
2341a246d1SDarrick J. Wong __u32 hi;
2441a246d1SDarrick J. Wong __u32 provided, calculated;
2541a246d1SDarrick J. Wong struct ext4_sb_info *sbi = EXT4_SB(sb);
2641a246d1SDarrick J. Wong
279aa5d32bSDmitry Monakhov if (!ext4_has_metadata_csum(sb))
2841a246d1SDarrick J. Wong return 1;
2941a246d1SDarrick J. Wong
3041a246d1SDarrick J. Wong provided = le16_to_cpu(gdp->bg_inode_bitmap_csum_lo);
3141a246d1SDarrick J. Wong calculated = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)bh->b_data, sz);
3241a246d1SDarrick J. Wong if (sbi->s_desc_size >= EXT4_BG_INODE_BITMAP_CSUM_HI_END) {
3341a246d1SDarrick J. Wong hi = le16_to_cpu(gdp->bg_inode_bitmap_csum_hi);
3441a246d1SDarrick J. Wong provided |= (hi << 16);
3541a246d1SDarrick J. Wong } else
3641a246d1SDarrick J. Wong calculated &= 0xFFFF;
3741a246d1SDarrick J. Wong
3841a246d1SDarrick J. Wong return provided == calculated;
3941a246d1SDarrick J. Wong }
4041a246d1SDarrick J. Wong
ext4_inode_bitmap_csum_set(struct super_block * sb,struct ext4_group_desc * gdp,struct buffer_head * bh,int sz)414fd873c8SKemeng Shi void ext4_inode_bitmap_csum_set(struct super_block *sb,
4241a246d1SDarrick J. Wong struct ext4_group_desc *gdp,
4341a246d1SDarrick J. Wong struct buffer_head *bh, int sz)
4441a246d1SDarrick J. Wong {
4541a246d1SDarrick J. Wong __u32 csum;
4641a246d1SDarrick J. Wong struct ext4_sb_info *sbi = EXT4_SB(sb);
4741a246d1SDarrick J. Wong
489aa5d32bSDmitry Monakhov if (!ext4_has_metadata_csum(sb))
4941a246d1SDarrick J. Wong return;
5041a246d1SDarrick J. Wong
5141a246d1SDarrick J. Wong csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)bh->b_data, sz);
5241a246d1SDarrick J. Wong gdp->bg_inode_bitmap_csum_lo = cpu_to_le16(csum & 0xFFFF);
5341a246d1SDarrick J. Wong if (sbi->s_desc_size >= EXT4_BG_INODE_BITMAP_CSUM_HI_END)
5441a246d1SDarrick J. Wong gdp->bg_inode_bitmap_csum_hi = cpu_to_le16(csum >> 16);
5541a246d1SDarrick J. Wong }
56fa77dcfaSDarrick J. Wong
ext4_block_bitmap_csum_verify(struct super_block * sb,struct ext4_group_desc * gdp,struct buffer_head * bh)5782483dfeSKemeng Shi int ext4_block_bitmap_csum_verify(struct super_block *sb,
58fa77dcfaSDarrick J. Wong struct ext4_group_desc *gdp,
5979f1ba49STao Ma struct buffer_head *bh)
60fa77dcfaSDarrick J. Wong {
61fa77dcfaSDarrick J. Wong __u32 hi;
62fa77dcfaSDarrick J. Wong __u32 provided, calculated;
63fa77dcfaSDarrick J. Wong struct ext4_sb_info *sbi = EXT4_SB(sb);
6479f1ba49STao Ma int sz = EXT4_CLUSTERS_PER_GROUP(sb) / 8;
65fa77dcfaSDarrick J. Wong
669aa5d32bSDmitry Monakhov if (!ext4_has_metadata_csum(sb))
67fa77dcfaSDarrick J. Wong return 1;
68fa77dcfaSDarrick J. Wong
69fa77dcfaSDarrick J. Wong provided = le16_to_cpu(gdp->bg_block_bitmap_csum_lo);
70fa77dcfaSDarrick J. Wong calculated = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)bh->b_data, sz);
71fa77dcfaSDarrick J. Wong if (sbi->s_desc_size >= EXT4_BG_BLOCK_BITMAP_CSUM_HI_END) {
72fa77dcfaSDarrick J. Wong hi = le16_to_cpu(gdp->bg_block_bitmap_csum_hi);
73fa77dcfaSDarrick J. Wong provided |= (hi << 16);
74fa77dcfaSDarrick J. Wong } else
75fa77dcfaSDarrick J. Wong calculated &= 0xFFFF;
76fa77dcfaSDarrick J. Wong
77*17809d3cSwuchi return provided == calculated;
78fa77dcfaSDarrick J. Wong }
79fa77dcfaSDarrick J. Wong
ext4_block_bitmap_csum_set(struct super_block * sb,struct ext4_group_desc * gdp,struct buffer_head * bh)801df9bde4SKemeng Shi void ext4_block_bitmap_csum_set(struct super_block *sb,
81fa77dcfaSDarrick J. Wong struct ext4_group_desc *gdp,
8279f1ba49STao Ma struct buffer_head *bh)
83fa77dcfaSDarrick J. Wong {
8479f1ba49STao Ma int sz = EXT4_CLUSTERS_PER_GROUP(sb) / 8;
85fa77dcfaSDarrick J. Wong __u32 csum;
86fa77dcfaSDarrick J. Wong struct ext4_sb_info *sbi = EXT4_SB(sb);
87fa77dcfaSDarrick J. Wong
889aa5d32bSDmitry Monakhov if (!ext4_has_metadata_csum(sb))
89fa77dcfaSDarrick J. Wong return;
90fa77dcfaSDarrick J. Wong
91fa77dcfaSDarrick J. Wong csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)bh->b_data, sz);
92fa77dcfaSDarrick J. Wong gdp->bg_block_bitmap_csum_lo = cpu_to_le16(csum & 0xFFFF);
93fa77dcfaSDarrick J. Wong if (sbi->s_desc_size >= EXT4_BG_BLOCK_BITMAP_CSUM_HI_END)
94fa77dcfaSDarrick J. Wong gdp->bg_block_bitmap_csum_hi = cpu_to_le16(csum >> 16);
95fa77dcfaSDarrick J. Wong }
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