Release 4.18 fs/minix/bitmap.c

// SPDX-License-Identifier: GPL-2.0
/*
 *  linux/fs/minix/bitmap.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */

/*
 * Modified for 680x0 by Hamish Macdonald
 * Fixed for 680x0 by Andreas Schwab
 */

/* bitmap.c contains the code that handles the inode and block bitmaps */

#include "minix.h"
#include <linux/buffer_head.h>
#include <linux/bitops.h>
#include <linux/sched.h>

static DEFINE_SPINLOCK(bitmap_lock);

/*
 * bitmap consists of blocks filled with 16bit words
 * bit set == busy, bit clear == free
 * endianness is a mess, but for counting zero bits it really doesn't matter...
 */


static __u32 count_free(struct buffer_head *map[], unsigned blocksize, __u32 numbits)
{
	__u32 sum = 0;
	unsigned blocks = DIV_ROUND_UP(numbits, blocksize * 8);

	while (blocks--) {
		unsigned words = blocksize / 2;
		__u16 *p = (__u16 *)(*map++)->b_data;
		while (words--)
			sum += 16 - hweight16(*p++);
	}

	return sum;
}

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Linus Torvalds (pre-git)
38
45.24%
4
66.67%
Al Viro
37
44.05%
1
16.67%
Josh Boyer
9
10.71%
1
16.67%
Total
84
100.00%
6
100.00%



void minix_free_block(struct inode *inode, unsigned long block)
{
	struct super_block *sb = inode->i_sb;
	struct minix_sb_info *sbi = minix_sb(sb);
	struct buffer_head *bh;
	int k = sb->s_blocksize_bits + 3;
	unsigned long bit, zone;

	if (block < sbi->s_firstdatazone || block >= sbi->s_nzones) {
		printk("Trying to free block not in datazone\n");
		return;
	}
	zone = block - sbi->s_firstdatazone + 1;
	bit = zone & ((1<<k) - 1);
	zone >>= k;
	if (zone >= sbi->s_zmap_blocks) {
		printk("minix_free_block: nonexistent bitmap buffer\n");
		return;
	}
	bh = sbi->s_zmap[zone];
	spin_lock(&bitmap_lock);
	if (!minix_test_and_clear_bit(bit, bh->b_data))
		printk("minix_free_block (%s:%lu): bit already cleared\n",
		       sb->s_id, block);
	spin_unlock(&bitmap_lock);
	mark_buffer_dirty(bh);
	return;
}

Contributors
Person
Tokens
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Commits
CommitProp
Linus Torvalds (pre-git)
117
69.23%
11
64.71%
Andries E. Brouwer
23
13.61%
1
5.88%
Brian Gerst
15
8.88%
1
5.88%
Al Viro
12
7.10%
2
11.76%
Denys Vlasenko
1
0.59%
1
5.88%
Linus Torvalds
1
0.59%
1
5.88%
Total
169
100.00%
17
100.00%



int minix_new_block(struct inode * inode)
{
	struct minix_sb_info *sbi = minix_sb(inode->i_sb);
	int bits_per_zone = 8 * inode->i_sb->s_blocksize;
	int i;

	for (i = 0; i < sbi->s_zmap_blocks; i++) {
		struct buffer_head *bh = sbi->s_zmap[i];
		int j;

		spin_lock(&bitmap_lock);
		j = minix_find_first_zero_bit(bh->b_data, bits_per_zone);
		if (j < bits_per_zone) {
			minix_set_bit(j, bh->b_data);
			spin_unlock(&bitmap_lock);
			mark_buffer_dirty(bh);
			j += i * bits_per_zone + sbi->s_firstdatazone-1;
			if (j < sbi->s_firstdatazone || j >= sbi->s_nzones)
				break;
			return j;
		}
		spin_unlock(&bitmap_lock);
	}
	return 0;
}

Contributors
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Tokens
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CommitProp
Linus Torvalds (pre-git)
86
56.58%
10
66.67%
Al Viro
35
23.03%
3
20.00%
Andries E. Brouwer
18
11.84%
1
6.67%
Brian Gerst
13
8.55%
1
6.67%
Total
152
100.00%
15
100.00%



unsigned long minix_count_free_blocks(struct super_block *sb)
{
	struct minix_sb_info *sbi = minix_sb(sb);
	u32 bits = sbi->s_nzones - sbi->s_firstdatazone + 1;

	return (count_free(sbi->s_zmap, sb->s_blocksize, bits)
		<< sbi->s_log_zone_size);
}

Contributors
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Josh Boyer
28
51.85%
1
16.67%
Linus Torvalds (pre-git)
19
35.19%
3
50.00%
Brian Gerst
5
9.26%
1
16.67%
Al Viro
2
3.70%
1
16.67%
Total
54
100.00%
6
100.00%


struct minix_inode *

minix_V1_raw_inode(struct super_block *sb, ino_t ino, struct buffer_head **bh)
{
	int block;
	struct minix_sb_info *sbi = minix_sb(sb);
	struct minix_inode *p;

	if (!ino || ino > sbi->s_ninodes) {
		printk("Bad inode number on dev %s: %ld is out of range\n",
		       sb->s_id, (long)ino);
		return NULL;
	}
	ino--;
	block = 2 + sbi->s_imap_blocks + sbi->s_zmap_blocks +
		 ino / MINIX_INODES_PER_BLOCK;
	*bh = sb_bread(sb, block);
	if (!*bh) {
		printk("Unable to read inode block\n");
		return NULL;
	}
	p = (void *)(*bh)->b_data;
	return p + ino % MINIX_INODES_PER_BLOCK;
}

Contributors
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Linus Torvalds (pre-git)
85
63.43%
4
40.00%
Linus Torvalds
42
31.34%
3
30.00%
Brian Gerst
3
2.24%
1
10.00%
Andrew Morton
3
2.24%
1
10.00%
Denys Vlasenko
1
0.75%
1
10.00%
Total
134
100.00%
10
100.00%


struct minix2_inode *

minix_V2_raw_inode(struct super_block *sb, ino_t ino, struct buffer_head **bh)
{
	int block;
	struct minix_sb_info *sbi = minix_sb(sb);
	struct minix2_inode *p;
	int minix2_inodes_per_block = sb->s_blocksize / sizeof(struct minix2_inode);

	*bh = NULL;
	if (!ino || ino > sbi->s_ninodes) {
		printk("Bad inode number on dev %s: %ld is out of range\n",
		       sb->s_id, (long)ino);
		return NULL;
	}
	ino--;
	block = 2 + sbi->s_imap_blocks + sbi->s_zmap_blocks +
		 ino / minix2_inodes_per_block;
	*bh = sb_bread(sb, block);
	if (!*bh) {
		printk("Unable to read inode block\n");
		return NULL;
	}
	p = (void *)(*bh)->b_data;
	return p + ino % minix2_inodes_per_block;
}

Contributors
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Linus Torvalds (pre-git)
85
55.92%
4
36.36%
Linus Torvalds
45
29.61%
3
27.27%
Andries E. Brouwer
15
9.87%
1
9.09%
Brian Gerst
3
1.97%
1
9.09%
Andrew Morton
3
1.97%
1
9.09%
Denys Vlasenko
1
0.66%
1
9.09%
Total
152
100.00%
11
100.00%

/* Clear the link count and mode of a deleted inode on disk. */



static void minix_clear_inode(struct inode *inode)
{
	struct buffer_head *bh = NULL;

	if (INODE_VERSION(inode) == MINIX_V1) {
		struct minix_inode *raw_inode;
		raw_inode = minix_V1_raw_inode(inode->i_sb, inode->i_ino, &bh);
		if (raw_inode) {
			raw_inode->i_nlinks = 0;
			raw_inode->i_mode = 0;
		}
	} else {
		struct minix2_inode *raw_inode;
		raw_inode = minix_V2_raw_inode(inode->i_sb, inode->i_ino, &bh);
		if (raw_inode) {
			raw_inode->i_nlinks = 0;
			raw_inode->i_mode = 0;
		}
	}
	if (bh) {
		mark_buffer_dirty(bh);
		brelse (bh);
	}
}

Contributors
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CommitProp
Linus Torvalds
83
65.87%
1
33.33%
Linus Torvalds (pre-git)
41
32.54%
1
33.33%
Andries E. Brouwer
2
1.59%
1
33.33%
Total
126
100.00%
3
100.00%



void minix_free_inode(struct inode * inode)
{
	struct super_block *sb = inode->i_sb;
	struct minix_sb_info *sbi = minix_sb(inode->i_sb);
	struct buffer_head *bh;
	int k = sb->s_blocksize_bits + 3;
	unsigned long ino, bit;

	ino = inode->i_ino;
	if (ino < 1 || ino > sbi->s_ninodes) {
		printk("minix_free_inode: inode 0 or nonexistent inode\n");
		return;
	}
	bit = ino & ((1<<k) - 1);
	ino >>= k;
	if (ino >= sbi->s_imap_blocks) {
		printk("minix_free_inode: nonexistent imap in superblock\n");
		return;
	}

	minix_clear_inode(inode);	/* clear on-disk copy */

	bh = sbi->s_imap[ino];
	spin_lock(&bitmap_lock);
	if (!minix_test_and_clear_bit(bit, bh->b_data))
		printk("minix_free_inode: bit %lu already cleared\n", bit);
	spin_unlock(&bitmap_lock);
	mark_buffer_dirty(bh);
}

Contributors
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Tokens
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CommitProp
Linus Torvalds (pre-git)
77
47.53%
9
60.00%
Andries E. Brouwer
55
33.95%
2
13.33%
Al Viro
29
17.90%
3
20.00%
Denys Vlasenko
1
0.62%
1
6.67%
Total
162
100.00%
15
100.00%



struct inode *minix_new_inode(const struct inode *dir, umode_t mode, int *error)
{
	struct super_block *sb = dir->i_sb;
	struct minix_sb_info *sbi = minix_sb(sb);
	struct inode *inode = new_inode(sb);
	struct buffer_head * bh;
	int bits_per_zone = 8 * sb->s_blocksize;
	unsigned long j;
	int i;

	if (!inode) {
		*error = -ENOMEM;
		return NULL;
	}
	j = bits_per_zone;
	bh = NULL;
	*error = -ENOSPC;
	spin_lock(&bitmap_lock);
	for (i = 0; i < sbi->s_imap_blocks; i++) {
		bh = sbi->s_imap[i];
		j = minix_find_first_zero_bit(bh->b_data, bits_per_zone);
		if (j < bits_per_zone)
			break;
	}
	if (!bh || j >= bits_per_zone) {
		spin_unlock(&bitmap_lock);
		iput(inode);
		return NULL;
	}
	if (minix_test_and_set_bit(j, bh->b_data)) {	/* shouldn't happen */
		spin_unlock(&bitmap_lock);
		printk("minix_new_inode: bit already set\n");
		iput(inode);
		return NULL;
	}
	spin_unlock(&bitmap_lock);
	mark_buffer_dirty(bh);
	j += i * bits_per_zone;
	if (!j || j > sbi->s_ninodes) {
		iput(inode);
		return NULL;
	}
	inode_init_owner(inode, dir, mode);
	inode->i_ino = j;
	inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
	inode->i_blocks = 0;
	memset(&minix_i(inode)->u, 0, sizeof(minix_i(inode)->u));
	insert_inode_hash(inode);
	mark_inode_dirty(inode);

	*error = 0;
	return inode;
}

Contributors
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CommitProp
Linus Torvalds (pre-git)
220
67.69%
18
72.00%
Al Viro
45
13.85%
3
12.00%
Andries E. Brouwer
24
7.38%
1
4.00%
Linus Torvalds
23
7.08%
1
4.00%
Dmitriy Monakhov
9
2.77%
1
4.00%
Deepa Dinamani
4
1.23%
1
4.00%
Total
325
100.00%
25
100.00%



unsigned long minix_count_free_inodes(struct super_block *sb)
{
	struct minix_sb_info *sbi = minix_sb(sb);
	u32 bits = sbi->s_ninodes + 1;

	return count_free(sbi->s_imap, sb->s_blocksize, bits);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Josh Boyer
24
54.55%
1
20.00%
Linus Torvalds (pre-git)
19
43.18%
3
60.00%
Al Viro
1
2.27%
1
20.00%
Total
44
100.00%
5
100.00%

Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
795
55.75%
26
53.06%
Linus Torvalds
194
13.60%
4
8.16%
Al Viro
169
11.85%
7
14.29%
Andries E. Brouwer
137
9.61%
2
4.08%
Josh Boyer
61
4.28%
1
2.04%
Brian Gerst
39
2.73%
1
2.04%
Dmitriy Monakhov
9
0.63%
1
2.04%
Andrew Morton
6
0.42%
1
2.04%
Denys Vlasenko
4
0.28%
1
2.04%
Deepa Dinamani
4
0.28%
1
2.04%
Christoph Hellwig
3
0.21%
1
2.04%
Alexey Dobriyan
3
0.21%
1
2.04%
Greg Kroah-Hartman
1
0.07%
1
2.04%
Adrian Bunk
1
0.07%
1
2.04%
Total
1426
100.00%
49
100.00%
Directory: fs/minix

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