[linux.git] / fs / qnx4 / bitmap.c

// SPDX-License-Identifier: GPL-2.0
/*
 * QNX4 file system, Linux implementation.
 *
 * Version : 0.2.1
 *
 * Using parts of the xiafs filesystem.
 *
 * History :
 *
 * 28-05-1998 by Richard Frowijn : first release.
 * 20-06-1998 by Frank Denis : basic optimisations.
 * 25-06-1998 by Frank Denis : qnx4_is_free, qnx4_set_bitmap, qnx4_bmap .
 * 28-06-1998 by Frank Denis : qnx4_free_inode (to be fixed) .
 */

#include <linux/buffer_head.h>
#include <linux/bitops.h>
#include "qnx4.h"

unsigned long qnx4_count_free_blocks(struct super_block *sb)
{
	int start = le32_to_cpu(qnx4_sb(sb)->BitMap->di_first_xtnt.xtnt_blk) - 1;
	int total = 0;
	int total_free = 0;
	int offset = 0;
	int size = le32_to_cpu(qnx4_sb(sb)->BitMap->di_size);
	struct buffer_head *bh;

	while (total < size) {
		int bytes = min(size - total, QNX4_BLOCK_SIZE);

		if ((bh = sb_bread(sb, start + offset)) == NULL) {
			printk(KERN_ERR "qnx4: I/O error in counting free blocks\n");
			break;
		}
		total_free += bytes * BITS_PER_BYTE -
				memweight(bh->b_data, bytes);
		brelse(bh);
		total += bytes;
		offset++;
	}

	return total_free;
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	/*
	3	* QNX4 file system, Linux implementation.
	4	*
	5	* Version : 0.2.1
	6	*
	7	* Using parts of the xiafs filesystem.
	8	*
	9	* History :
	10	*
	11	* 28-05-1998 by Richard Frowijn : first release.
	12	* 20-06-1998 by Frank Denis : basic optimisations.
	13	* 25-06-1998 by Frank Denis : qnx4_is_free, qnx4_set_bitmap, qnx4_bmap .
	14	* 28-06-1998 by Frank Denis : qnx4_free_inode (to be fixed) .
	15	*/
	16
1da177e4 LT	17	#include <linux/buffer_head.h>
1da177e4 LT	18	#include <linux/bitops.h>
964f5369	19	#include "qnx4.h"
1da177e4	20
1da177e4 LT	21	unsigned long qnx4_count_free_blocks(struct super_block *sb)
	22	{
	23	int start = le32_to_cpu(qnx4_sb(sb)->BitMap->di_first_xtnt.xtnt_blk) - 1;
	24	int total = 0;
	25	int total_free = 0;
	26	int offset = 0;
	27	int size = le32_to_cpu(qnx4_sb(sb)->BitMap->di_size);
	28	struct buffer_head *bh;
	29
	30	while (total < size) {
9b58f6d4 AM	31	int bytes = min(size - total, QNX4_BLOCK_SIZE);
9b58f6d4 AM	32
1da177e4	33	if ((bh = sb_bread(sb, start + offset)) == NULL) {
891ddb95	34	printk(KERN_ERR "qnx4: I/O error in counting free blocks\n");
1da177e4 LT	35	break;
1da177e4 LT	36	}
9b58f6d4 AM	37	total_free += bytes * BITS_PER_BYTE -
9b58f6d4 AM	38	memweight(bh->b_data, bytes);
1da177e4	39	brelse(bh);
9b58f6d4	40	total += bytes;
1da177e4 LT	41	offset++;
	42	}
	43
	44	return total_free;
	45	}