path: root/fs/ufs/balloc.c

/*
 *  linux/fs/ufs/balloc.c
 *
 * Copyright (C) 1998
 * Daniel Pirkl <daniel.pirkl@email.cz>
 * Charles University, Faculty of Mathematics and Physics
 */

#include <linux/fs.h>
#include <linux/ufs_fs.h>
#include <linux/stat.h>
#include <linux/time.h>
#include <linux/string.h>
#include <linux/quotaops.h>
#include <linux/buffer_head.h>
#include <linux/capability.h>
#include <linux/sched.h>
#include <linux/bitops.h>
#include <asm/byteorder.h>

#include "swab.h"
#include "util.h"

static unsigned ufs_add_fragments (struct inode *, unsigned, unsigned, unsigned, int *);
static unsigned ufs_alloc_fragments (struct inode *, unsigned, unsigned, unsigned, int *);
static unsigned ufs_alloccg_block (struct inode *, struct ufs_cg_private_info *, unsigned, int *);
static unsigned ufs_bitmap_search (struct super_block *, struct ufs_cg_private_info *, unsigned, unsigned);
static unsigned char ufs_fragtable_8fpb[], ufs_fragtable_other[];
static void ufs_clusteracct(struct super_block *, struct ufs_cg_private_info *, unsigned, int);

/*
 * Free 'count' fragments from fragment number 'fragment'
 */
void ufs_free_fragments(struct inode *inode, unsigned fragment, unsigned count)
{
	struct super_block * sb;
	struct ufs_sb_private_info * uspi;
	struct ufs_super_block_first * usb1;
	struct ufs_cg_private_info * ucpi;
	struct ufs_cylinder_group * ucg;
	unsigned cgno, bit, end_bit, bbase, blkmap, i, blkno, cylno;
	
	sb = inode->i_sb;
	uspi = UFS_SB(sb)->s_uspi;
	usb1 = ubh_get_usb_first(uspi);
	
	UFSD("ENTER, fragment %u, count %u\n", fragment, count);
	
	if (ufs_fragnum(fragment) + count > uspi->s_fpg)
		ufs_error (sb, "ufs_free_fragments", "internal error");
	
	lock_super(sb);
	
	cgno = ufs_dtog(fragment);
	bit = ufs_dtogd(fragment);
	if (cgno >= uspi->s_ncg) {
		ufs_panic (sb, "ufs_free_fragments", "freeing blocks are outside device");
		goto failed;
	}
		
	ucpi = ufs_load_cylinder (sb, cgno);
	if (!ucpi) 
		goto failed;
	ucg = ubh_get_ucg (UCPI_UBH(ucpi));
	if (!ufs_cg_chkmagic(sb, ucg)) {
		ufs_panic (sb, "ufs_free_fragments", "internal error, bad magic number on cg %u", cgno);
		goto failed;
	}

	end_bit = bit + count;
	bbase = ufs_blknum (bit);
	blkmap = ubh_blkmap (UCPI_UBH(ucpi), ucpi->c_freeoff, bbase);
	ufs_fragacct (sb, blkmap, ucg->cg_frsum, -1);
	for (i = bit; i < end_bit; i++) {
		if (ubh_isclr (UCPI_UBH(ucpi), ucpi->c_freeoff, i))
			ubh_setbit (UCPI_UBH(ucpi), ucpi->c_freeoff, i);
		else 
			ufs_error (sb, "ufs_free_fragments",
				   "bit already cleared for fragment %u", i);
	}
	
	DQUOT_FREE_BLOCK (inode, count);

	
	fs32_add(sb, &ucg->cg_cs.cs_nffree, count);
	uspi->cs_total.cs_nffree += count;
	fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, count);
	blkmap = ubh_blkmap (UCPI_UBH(ucpi), ucpi->c_freeoff, bbase);
	ufs_fragacct(sb, blkmap, ucg->cg_frsum, 1);

	/*
	 * Trying to reassemble free fragments into block
	 */
	blkno = ufs_fragstoblks (bbase);
	if (ubh_isblockset(UCPI_UBH(ucpi), ucpi->c_freeoff, blkno)) {
		fs32_sub(sb, &ucg->cg_cs.cs_nffree, uspi->s_fpb);
		uspi->cs_total.cs_nffree -= uspi->s_fpb;
		fs32_sub(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nffree, uspi->s_fpb);
		if ((UFS_SB(sb)->s_flags & UFS_CG_MASK) == UFS_CG_44BSD)
			ufs_clusteracct (sb, ucpi, blkno, 1);
		fs32_add(sb, &ucg->cg_cs.cs_nbfree, 1);
		uspi->cs_total.cs_nbfree++;
		fs32_add(sb, &UFS_SB(sb)->fs_cs(cgno).cs_nbfree, 1);
		cylno = ufs_cbtocylno (bbase);
		fs16_add(sb, &ubh_cg_blks(ucpi, cylno, ufs_cbtorpos(bbase)), 1);
		fs32_add(sb, &ubh_cg_blktot(ucpi, cylno), 1);
	}
	
	ubh_mark_buffer_dirty (USPI_UBH(uspi));
	ubh_mark_buffer_dirty (UCPI_UBH(ucpi));
	if (sb->s_flags & MS_SYNCHRONOUS) {
		ubh_ll_rw_block(SWRITE, UCPI_UBH(ucpi));
		ubh_wait_on_buffer (UCPI_UBH(ucpi));
	}
	sb->s_dirt = 1;
	
	unlock_super (sb);