1  | 
     | 
     | 
    /*	$OpenBSD: ffs_subr.c,v 1.4 2016/10/22 19:43:50 natano Exp $	*/  | 
    
    
    2  | 
     | 
     | 
    /*	$NetBSD: ffs_subr.c,v 1.49 2016/05/07 11:59:08 maxv Exp $	*/  | 
    
    
    3  | 
     | 
     | 
     | 
    
    
    4  | 
     | 
     | 
    /*  | 
    
    
    5  | 
     | 
     | 
     * Copyright (c) 1982, 1986, 1989, 1993  | 
    
    
    6  | 
     | 
     | 
     *	The Regents of the University of California.  All rights reserved.  | 
    
    
    7  | 
     | 
     | 
     *  | 
    
    
    8  | 
     | 
     | 
     * Redistribution and use in source and binary forms, with or without  | 
    
    
    9  | 
     | 
     | 
     * modification, are permitted provided that the following conditions  | 
    
    
    10  | 
     | 
     | 
     * are met:  | 
    
    
    11  | 
     | 
     | 
     * 1. Redistributions of source code must retain the above copyright  | 
    
    
    12  | 
     | 
     | 
     *    notice, this list of conditions and the following disclaimer.  | 
    
    
    13  | 
     | 
     | 
     * 2. Redistributions in binary form must reproduce the above copyright  | 
    
    
    14  | 
     | 
     | 
     *    notice, this list of conditions and the following disclaimer in the  | 
    
    
    15  | 
     | 
     | 
     *    documentation and/or other materials provided with the distribution.  | 
    
    
    16  | 
     | 
     | 
     * 3. Neither the name of the University nor the names of its contributors  | 
    
    
    17  | 
     | 
     | 
     *    may be used to endorse or promote products derived from this software  | 
    
    
    18  | 
     | 
     | 
     *    without specific prior written permission.  | 
    
    
    19  | 
     | 
     | 
     *  | 
    
    
    20  | 
     | 
     | 
     * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND  | 
    
    
    21  | 
     | 
     | 
     * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE  | 
    
    
    22  | 
     | 
     | 
     * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE  | 
    
    
    23  | 
     | 
     | 
     * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE  | 
    
    
    24  | 
     | 
     | 
     * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL  | 
    
    
    25  | 
     | 
     | 
     * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS  | 
    
    
    26  | 
     | 
     | 
     * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)  | 
    
    
    27  | 
     | 
     | 
     * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT  | 
    
    
    28  | 
     | 
     | 
     * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY  | 
    
    
    29  | 
     | 
     | 
     * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF  | 
    
    
    30  | 
     | 
     | 
     * SUCH DAMAGE.  | 
    
    
    31  | 
     | 
     | 
     *  | 
    
    
    32  | 
     | 
     | 
     *	@(#)ffs_subr.c	8.5 (Berkeley) 3/21/95  | 
    
    
    33  | 
     | 
     | 
     */  | 
    
    
    34  | 
     | 
     | 
     | 
    
    
    35  | 
     | 
     | 
    #include <sys/param.h>  | 
    
    
    36  | 
     | 
     | 
     | 
    
    
    37  | 
     | 
     | 
    #include <ufs/ufs/dinode.h>  | 
    
    
    38  | 
     | 
     | 
    #include <ufs/ffs/fs.h>  | 
    
    
    39  | 
     | 
     | 
     | 
    
    
    40  | 
     | 
     | 
    #include <err.h>  | 
    
    
    41  | 
     | 
     | 
     | 
    
    
    42  | 
     | 
     | 
    #include "ffs/ffs_extern.h"  | 
    
    
    43  | 
     | 
     | 
     | 
    
    
    44  | 
     | 
     | 
     | 
    
    
    45  | 
     | 
     | 
    /*  | 
    
    
    46  | 
     | 
     | 
     * block operations  | 
    
    
    47  | 
     | 
     | 
     *  | 
    
    
    48  | 
     | 
     | 
     * check if a block is available  | 
    
    
    49  | 
     | 
     | 
     *  returns true if all the correponding bits in the free map are 1  | 
    
    
    50  | 
     | 
     | 
     *  returns false if any corresponding bit in the free map is 0  | 
    
    
    51  | 
     | 
     | 
     */  | 
    
    
    52  | 
     | 
     | 
    int  | 
    
    
    53  | 
     | 
     | 
    ffs_isblock(struct fs *fs, u_char *cp, int32_t h)  | 
    
    
    54  | 
     | 
     | 
    { | 
    
    
    55  | 
     | 
     | 
    	u_char mask;  | 
    
    
    56  | 
     | 
     | 
     | 
    
    
    57  | 
     | 
     | 
    	switch ((int)fs->fs_fragshift) { | 
    
    
    58  | 
     | 
     | 
    	case 3:  | 
    
    
    59  | 
     | 
     | 
    		return (cp[h] == 0xff);  | 
    
    
    60  | 
     | 
     | 
    	case 2:  | 
    
    
    61  | 
     | 
     | 
    		mask = 0x0f << ((h & 0x1) << 2);  | 
    
    
    62  | 
     | 
     | 
    		return ((cp[h >> 1] & mask) == mask);  | 
    
    
    63  | 
     | 
     | 
    	case 1:  | 
    
    
    64  | 
     | 
     | 
    		mask = 0x03 << ((h & 0x3) << 1);  | 
    
    
    65  | 
     | 
     | 
    		return ((cp[h >> 2] & mask) == mask);  | 
    
    
    66  | 
     | 
     | 
    	case 0:  | 
    
    
    67  | 
     | 
     | 
    		mask = 0x01 << (h & 0x7);  | 
    
    
    68  | 
     | 
     | 
    		return ((cp[h >> 3] & mask) == mask);  | 
    
    
    69  | 
     | 
     | 
    	default:  | 
    
    
    70  | 
     | 
     | 
    		errx(1, "ffs_isblock: unknown fs_fragshift %d",  | 
    
    
    71  | 
     | 
     | 
    		    (int)fs->fs_fragshift);  | 
    
    
    72  | 
     | 
     | 
    	}  | 
    
    
    73  | 
     | 
     | 
    }  | 
    
    
    74  | 
     | 
     | 
     | 
    
    
    75  | 
     | 
     | 
    /*  | 
    
    
    76  | 
     | 
     | 
     * take a block out of the map  | 
    
    
    77  | 
     | 
     | 
     */  | 
    
    
    78  | 
     | 
     | 
    void  | 
    
    
    79  | 
     | 
     | 
    ffs_clrblock(struct fs *fs, u_char *cp, int32_t h)  | 
    
    
    80  | 
     | 
     | 
    { | 
    
    
    81  | 
     | 
     | 
     | 
    
    
    82  | 
     | 
     | 
    	switch ((int)fs->fs_fragshift) { | 
    
    
    83  | 
     | 
     | 
    	case 3:  | 
    
    
    84  | 
     | 
     | 
    		cp[h] = 0;  | 
    
    
    85  | 
     | 
     | 
    		return;  | 
    
    
    86  | 
     | 
     | 
    	case 2:  | 
    
    
    87  | 
     | 
     | 
    		cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));  | 
    
    
    88  | 
     | 
     | 
    		return;  | 
    
    
    89  | 
     | 
     | 
    	case 1:  | 
    
    
    90  | 
     | 
     | 
    		cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));  | 
    
    
    91  | 
     | 
     | 
    		return;  | 
    
    
    92  | 
     | 
     | 
    	case 0:  | 
    
    
    93  | 
     | 
     | 
    		cp[h >> 3] &= ~(0x01 << (h & 0x7));  | 
    
    
    94  | 
     | 
     | 
    		return;  | 
    
    
    95  | 
     | 
     | 
    	default:  | 
    
    
    96  | 
     | 
     | 
    		errx(1, "ffs_clrblock: unknown fs_fragshift %d",  | 
    
    
    97  | 
     | 
     | 
    		    (int)fs->fs_fragshift);  | 
    
    
    98  | 
     | 
     | 
    	}  | 
    
    
    99  | 
     | 
     | 
    }  | 
    
    
    100  | 
     | 
     | 
     | 
    
    
    101  | 
     | 
     | 
    /*  | 
    
    
    102  | 
     | 
     | 
     * put a block into the map  | 
    
    
    103  | 
     | 
     | 
     */  | 
    
    
    104  | 
     | 
     | 
    void  | 
    
    
    105  | 
     | 
     | 
    ffs_setblock(struct fs *fs, u_char *cp, int32_t h)  | 
    
    
    106  | 
     | 
     | 
    { | 
    
    
    107  | 
     | 
     | 
     | 
    
    
    108  | 
     | 
     | 
    	switch ((int)fs->fs_fragshift) { | 
    
    
    109  | 
     | 
     | 
    	case 3:  | 
    
    
    110  | 
     | 
     | 
    		cp[h] = 0xff;  | 
    
    
    111  | 
     | 
     | 
    		return;  | 
    
    
    112  | 
     | 
     | 
    	case 2:  | 
    
    
    113  | 
     | 
     | 
    		cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));  | 
    
    
    114  | 
     | 
     | 
    		return;  | 
    
    
    115  | 
     | 
     | 
    	case 1:  | 
    
    
    116  | 
     | 
     | 
    		cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));  | 
    
    
    117  | 
     | 
     | 
    		return;  | 
    
    
    118  | 
     | 
     | 
    	case 0:  | 
    
    
    119  | 
     | 
     | 
    		cp[h >> 3] |= (0x01 << (h & 0x7));  | 
    
    
    120  | 
     | 
     | 
    		return;  | 
    
    
    121  | 
     | 
     | 
    	default:  | 
    
    
    122  | 
     | 
     | 
    		errx(1, "ffs_setblock: unknown fs_fragshift %d",  | 
    
    
    123  | 
     | 
     | 
    		    (int)fs->fs_fragshift);  | 
    
    
    124  | 
     | 
     | 
    	}  | 
    
    
    125  | 
     | 
     | 
    }  | 
    
    
    126  | 
     | 
     | 
     | 
    
    
    127  | 
     | 
     | 
    /*  | 
    
    
    128  | 
     | 
     | 
     * Update the cluster map because of an allocation or free.  | 
    
    
    129  | 
     | 
     | 
     *  | 
    
    
    130  | 
     | 
     | 
     * Cnt == 1 means free; cnt == -1 means allocating.  | 
    
    
    131  | 
     | 
     | 
     */  | 
    
    
    132  | 
     | 
     | 
    void  | 
    
    
    133  | 
     | 
     | 
    ffs_clusteracct(struct fs *fs, struct cg *cgp, int32_t blkno, int cnt)  | 
    
    
    134  | 
     | 
     | 
    { | 
    
    
    135  | 
     | 
     | 
    	int32_t *sump;  | 
    
    
    136  | 
     | 
     | 
    	int32_t *lp;  | 
    
    
    137  | 
     | 
     | 
    	u_char *freemapp, *mapp;  | 
    
    
    138  | 
     | 
     | 
    	int i, start, end, forw, back, map, bit;  | 
    
    
    139  | 
     | 
     | 
     | 
    
    
    140  | 
     | 
     | 
    	/* KASSERT(mutex_owned(&ump->um_lock)); */  | 
    
    
    141  | 
     | 
     | 
     | 
    
    
    142  | 
     | 
     | 
    	if (fs->fs_contigsumsize <= 0)  | 
    
    
    143  | 
     | 
     | 
    		return;  | 
    
    
    144  | 
     | 
     | 
    	freemapp = cg_clustersfree(cgp);  | 
    
    
    145  | 
     | 
     | 
    	sump = cg_clustersum(cgp);  | 
    
    
    146  | 
     | 
     | 
    	/*  | 
    
    
    147  | 
     | 
     | 
    	 * Allocate or clear the actual block.  | 
    
    
    148  | 
     | 
     | 
    	 */  | 
    
    
    149  | 
     | 
     | 
    	if (cnt > 0)  | 
    
    
    150  | 
     | 
     | 
    		setbit(freemapp, blkno);  | 
    
    
    151  | 
     | 
     | 
    	else  | 
    
    
    152  | 
     | 
     | 
    		clrbit(freemapp, blkno);  | 
    
    
    153  | 
     | 
     | 
    	/*  | 
    
    
    154  | 
     | 
     | 
    	 * Find the size of the cluster going forward.  | 
    
    
    155  | 
     | 
     | 
    	 */  | 
    
    
    156  | 
     | 
     | 
    	start = blkno + 1;  | 
    
    
    157  | 
     | 
     | 
    	end = start + fs->fs_contigsumsize;  | 
    
    
    158  | 
     | 
     | 
    	if ((uint32_t)end >= cgp->cg_nclusterblks)  | 
    
    
    159  | 
     | 
     | 
    		end = cgp->cg_nclusterblks;  | 
    
    
    160  | 
     | 
     | 
    	mapp = &freemapp[start / NBBY];  | 
    
    
    161  | 
     | 
     | 
    	map = *mapp++;  | 
    
    
    162  | 
     | 
     | 
    	bit = 1 << (start % NBBY);  | 
    
    
    163  | 
     | 
     | 
    	for (i = start; i < end; i++) { | 
    
    
    164  | 
     | 
     | 
    		if ((map & bit) == 0)  | 
    
    
    165  | 
     | 
     | 
    			break;  | 
    
    
    166  | 
     | 
     | 
    		if ((i & (NBBY - 1)) != (NBBY - 1)) { | 
    
    
    167  | 
     | 
     | 
    			bit <<= 1;  | 
    
    
    168  | 
     | 
     | 
    		} else { | 
    
    
    169  | 
     | 
     | 
    			map = *mapp++;  | 
    
    
    170  | 
     | 
     | 
    			bit = 1;  | 
    
    
    171  | 
     | 
     | 
    		}  | 
    
    
    172  | 
     | 
     | 
    	}  | 
    
    
    173  | 
     | 
     | 
    	forw = i - start;  | 
    
    
    174  | 
     | 
     | 
    	/*  | 
    
    
    175  | 
     | 
     | 
    	 * Find the size of the cluster going backward.  | 
    
    
    176  | 
     | 
     | 
    	 */  | 
    
    
    177  | 
     | 
     | 
    	start = blkno - 1;  | 
    
    
    178  | 
     | 
     | 
    	end = start - fs->fs_contigsumsize;  | 
    
    
    179  | 
     | 
     | 
    	if (end < 0)  | 
    
    
    180  | 
     | 
     | 
    		end = -1;  | 
    
    
    181  | 
     | 
     | 
    	mapp = &freemapp[start / NBBY];  | 
    
    
    182  | 
     | 
     | 
    	map = *mapp--;  | 
    
    
    183  | 
     | 
     | 
    	bit = 1 << (start % NBBY);  | 
    
    
    184  | 
     | 
     | 
    	for (i = start; i > end; i--) { | 
    
    
    185  | 
     | 
     | 
    		if ((map & bit) == 0)  | 
    
    
    186  | 
     | 
     | 
    			break;  | 
    
    
    187  | 
     | 
     | 
    		if ((i & (NBBY - 1)) != 0) { | 
    
    
    188  | 
     | 
     | 
    			bit >>= 1;  | 
    
    
    189  | 
     | 
     | 
    		} else { | 
    
    
    190  | 
     | 
     | 
    			map = *mapp--;  | 
    
    
    191  | 
     | 
     | 
    			bit = 1 << (NBBY - 1);  | 
    
    
    192  | 
     | 
     | 
    		}  | 
    
    
    193  | 
     | 
     | 
    	}  | 
    
    
    194  | 
     | 
     | 
    	back = start - i;  | 
    
    
    195  | 
     | 
     | 
    	/*  | 
    
    
    196  | 
     | 
     | 
    	 * Account for old cluster and the possibly new forward and  | 
    
    
    197  | 
     | 
     | 
    	 * back clusters.  | 
    
    
    198  | 
     | 
     | 
    	 */  | 
    
    
    199  | 
     | 
     | 
    	i = back + forw + 1;  | 
    
    
    200  | 
     | 
     | 
    	if (i > fs->fs_contigsumsize)  | 
    
    
    201  | 
     | 
     | 
    		i = fs->fs_contigsumsize;  | 
    
    
    202  | 
     | 
     | 
    	sump[i] += cnt;  | 
    
    
    203  | 
     | 
     | 
    	if (back > 0)  | 
    
    
    204  | 
     | 
     | 
    		sump[back] -= cnt;  | 
    
    
    205  | 
     | 
     | 
    	if (forw > 0)  | 
    
    
    206  | 
     | 
     | 
    		sump[forw] -= cnt;  | 
    
    
    207  | 
     | 
     | 
     | 
    
    
    208  | 
     | 
     | 
    	/*  | 
    
    
    209  | 
     | 
     | 
    	 * Update cluster summary information.  | 
    
    
    210  | 
     | 
     | 
    	 */  | 
    
    
    211  | 
     | 
     | 
    	lp = &sump[fs->fs_contigsumsize];  | 
    
    
    212  | 
     | 
     | 
    	for (i = fs->fs_contigsumsize; i > 0; i--)  | 
    
    
    213  | 
     | 
     | 
    		if (*lp-- > 0)  | 
    
    
    214  | 
     | 
     | 
    			break;  | 
    
    
    215  | 
     | 
     | 
    }  |