patch-2.1.21 linux/fs/xiafs/bitmap.c

• Lines: 390
• Date: Thu Jan 1 02:00:00 1970
• Orig file: v2.1.20/linux/fs/xiafs/bitmap.c
• Orig date: Sun Nov 26 19:23:10 1995

diff -u --recursive --new-file v2.1.20/linux/fs/xiafs/bitmap.c linux/fs/xiafs/bitmap.c
@@ -1,389 +0,0 @@
-/*
- *  linux/fs/xiafs/bitmap.c
- *
- *  Copyright (C) Q. Frank Xia, 1993.
- *  
- *  Based on Linus' minix/bitmap.c
- *  Copyright (C) Linus Torvalds, 1991, 1992.
- *  
- *  This software may be redistributed per Linux Copyright.
- */
-
-/* bitmap.c contains the code that handles the inode and block bitmaps */
-
-#include <linux/sched.h>
-#include <linux/locks.h>
-#include <linux/xia_fs.h>
-#include <linux/stat.h>
-#include <linux/kernel.h>
-#include <linux/string.h>
-
-#include <asm/bitops.h>
-
-#include "xiafs_mac.h"
-
-
-char internal_error_message[]="XIA-FS: internal error %s %d\n"; 
-
-static int find_first_zero(struct buffer_head *bh, int start_bit, int end_bit) 
-{
-    /* This routine searches first 0 bit from (start_bit) to (end_bit-1).
-     * If found the bit is set to 1 and the bit # is returned, otherwise,
-     * -1 is returned. Race condition is avoid by using "btsl" and 
-     * "goto repeat".  ---Frank.
-     */
-
-    int end, i, j, tmp;
-    u_long *bmap;
-
-    bmap=(u_long *)bh->b_data;
-    end = end_bit >> 5;
-
-repeat:
-    i=start_bit >> 5;
-    if ( (tmp=(~bmap[i]) & (0xffffffff << (start_bit & 31))) )        
-        goto zone_found;
-    while (++i < end)
-        if (~bmap[i]) {
-	    tmp=~bmap[i];
-	    goto zone_found;
-	}
-    if ( !(tmp=~bmap[i] & ((1 << (end_bit & 31)) -1)) )
-        return -1;
-zone_found:    
-    for (j=0; j < 32; j++)
-        if (tmp & (1 << j))
-	    break;
-    if (set_bit(j,bmap+i)) {
-        start_bit=j + (i << 5) + 1;
-	goto repeat;
-    }
-    mark_buffer_dirty(bh, 1);
-    return j + (i << 5);
-}
-
-static void clear_buf(struct buffer_head * bh) 
-{
-    register int i;
-    register long * lp;
-
-    lp=(long *)bh->b_data;
-    for (i= bh->b_size >> 2; i-- > 0; )
-        *lp++=0;
-}
-
-static void que(struct buffer_head * bmap[], int bznr[], int pos)
-{
-    struct buffer_head * tbh;
-    int tmp;
-    int i;
-    
-    tbh=bmap[pos];
-    tmp=bznr[pos];
-    for (i=pos; i > 0; i--) {
-        bmap[i]=bmap[i-1];
-	bznr[i]=bznr[i-1];
-    }
-    bmap[0]=tbh;
-    bznr[0]=tmp;
-}
-
-#define get_imap_zone(sb, bit_nr, not_que) \
-      	get__map_zone((sb), (sb)->u.xiafs_sb.s_imap_buf, \
-		      (sb)->u.xiafs_sb.s_imap_iznr, \
-		      (sb)->u.xiafs_sb.s_imap_cached, 1, \
-		      (sb)->u.xiafs_sb.s_imap_zones, _XIAFS_IMAP_SLOTS, \
-		      bit_nr, not_que)
-
-#define get_zmap_zone(sb, bit_nr, not_que) \
-      	get__map_zone((sb), (sb)->u.xiafs_sb.s_zmap_buf, \
-		      (sb)->u.xiafs_sb.s_zmap_zznr, \
-		      (sb)->u.xiafs_sb.s_zmap_cached, \
-		      1+(sb)->u.xiafs_sb.s_imap_zones, \
-		      (sb)->u.xiafs_sb.s_zmap_zones, _XIAFS_ZMAP_SLOTS, \
-		      bit_nr, not_que)
-
-static struct buffer_head * 
-get__map_zone(struct super_block *sb, struct buffer_head * bmap_buf[],
-	  int bznr[], u_char cache, int first_zone, 
-	  int bmap_zones, int slots, u_long bit_nr, int * not_que)
-{
-    struct buffer_head * tmp_bh;
-    int z_nr, i;
-
-    z_nr = bit_nr >> XIAFS_BITS_PER_Z_BITS(sb);
-    if (z_nr >= bmap_zones) {
-        printk("XIA-FS: bad inode/zone number (%s %d)\n", WHERE_ERR);
-	return NULL;
-    }
-    if (!cache)
-        return bmap_buf[z_nr];
-    lock_super(sb);
-    for (i=0; i < slots; i++) 
-        if (bznr[i]==z_nr)
-	    break;
-    if (i < slots) {			/* cache hit */
-        if (not_que) {
-	    *not_que=i;
-	    return bmap_buf[i];
-	} else {
-	    que(bmap_buf, bznr, i);
-	    return bmap_buf[0];
-	}
-    }
-    tmp_bh=bread(sb->s_dev, z_nr+first_zone, XIAFS_ZSIZE(sb)); /* cache not hit */
-    if (!tmp_bh) {
-        printk("XIA-FS: read bitmap failed (%s %d)\n", WHERE_ERR);
-	unlock_super(sb);
-	return NULL;
-    }
-    brelse(bmap_buf[slots-1]);
-    bmap_buf[slots-1]=tmp_bh;
-    bznr[slots-1]=z_nr;
-    if (not_que)
-        *not_que=slots-1;
-    else
-        que(bmap_buf, bznr, slots-1);
-    return tmp_bh;
-}
-
-#define xiafs_unlock_super(sb, cache)	if (cache) unlock_super(sb);
-
-#define get_free_ibit(sb, prev_bit) \
-   	get_free__bit(sb, sb->u.xiafs_sb.s_imap_buf, \
-		      sb->u.xiafs_sb.s_imap_iznr, \
-		      sb->u.xiafs_sb.s_imap_cached, \
-		      1, sb->u.xiafs_sb.s_imap_zones, \
-		      _XIAFS_IMAP_SLOTS, prev_bit);
-
-#define get_free_zbit(sb, prev_bit) \
-   	get_free__bit(sb, sb->u.xiafs_sb.s_zmap_buf, \
-		      sb->u.xiafs_sb.s_zmap_zznr, \
-		      sb->u.xiafs_sb.s_zmap_cached, \
-		      1 + sb->u.xiafs_sb.s_imap_zones, \
-		      sb->u.xiafs_sb.s_zmap_zones, \
-		      _XIAFS_ZMAP_SLOTS, prev_bit);
-
-static u_long 
-get_free__bit(struct super_block *sb, struct buffer_head * bmap_buf[],
-	      int bznr[], u_char cache, int first_zone, int bmap_zones, 
-	      int slots, u_long prev_bit)
-{
-    struct buffer_head * bh;
-    int not_done=0;
-    u_long pos, start_bit, end_bit, total_bits;
-    int z_nr, tmp;
- 
-    total_bits=bmap_zones << XIAFS_BITS_PER_Z_BITS(sb); 
-    if (prev_bit >= total_bits)
-        prev_bit=0;
-    pos=prev_bit+1;
-    end_bit=XIAFS_BITS_PER_Z(sb);
-
-    do {
-        if (pos >= total_bits)
-	    pos=0;
-        if (!not_done) {		/* first time */
-	    not_done=1;
-	    start_bit= pos & (end_bit-1);     
-	} else 
-	    start_bit=0;
-	if ( pos < prev_bit && pos+end_bit >= prev_bit) {   /* last time */
-	    not_done=0;
-	    end_bit=prev_bit & (end_bit-1);   /* only here end_bit modified */
-	}
-        bh = get__map_zone(sb, bmap_buf, bznr, cache, first_zone, 
-			   bmap_zones, slots, pos, &z_nr);
-	if (!bh)
-	    return 0;
-	tmp=find_first_zero(bh, start_bit, end_bit);
-	if (tmp >= 0)
-	    break;
-	xiafs_unlock_super(sb, sb->u.xiafs_sb.s_zmap_cached);
-	pos=(pos & ~(end_bit-1))+end_bit;
-    } while (not_done);
-
-    if (tmp < 0) 
-        return 0;
-    if (cache)
-      que(bmap_buf, bznr, z_nr);
-    xiafs_unlock_super(sb, cache);
-    return (pos & ~(XIAFS_BITS_PER_Z(sb)-1))+tmp;
-}
-
-void xiafs_free_zone(struct super_block * sb, int d_addr)
-{
-    struct buffer_head * bh;
-    unsigned int bit, offset;
-
-    if (!sb) {
-        printk(INTERN_ERR);
-	return;
-    }
-    if (d_addr < sb->u.xiafs_sb.s_firstdatazone ||
-	d_addr >= sb->u.xiafs_sb.s_nzones) {
-        printk("XIA-FS: bad zone number (%s %d)\n", WHERE_ERR);
-	return;
-    }
-    bh = get_hash_table(sb->s_dev, d_addr, XIAFS_ZSIZE(sb));
-    if (bh)
-        mark_buffer_clean(bh);
-    brelse(bh);
-    bit=d_addr - sb->u.xiafs_sb.s_firstdatazone + 1;
-    bh = get_zmap_zone(sb, bit, NULL);
-    if (!bh)
-	return;
-    offset = bit & (XIAFS_BITS_PER_Z(sb) -1);
-    if (!clear_bit(offset, bh->b_data))
-        printk("XIA-FS: dev %s"
-	       " block bit %u (0x%x) already cleared (%s %d)\n",
-	       kdevname(sb->s_dev), bit, bit, WHERE_ERR);
-    mark_buffer_dirty(bh, 1);
-    xiafs_unlock_super(sb, sb->u.xiafs_sb.s_zmap_cached);
-}
-
-int xiafs_new_zone(struct super_block * sb, u_long prev_addr)
-{
-    struct buffer_head * bh;
-    int prev_znr, tmp;
-
-    if (!sb) {
-        printk(INTERN_ERR);
-	return 0;
-    }
-    if (prev_addr < sb->u.xiafs_sb.s_firstdatazone || 
-	prev_addr >= sb->u.xiafs_sb.s_nzones) {
-        prev_addr=sb->u.xiafs_sb.s_firstdatazone;
-    }      
-    prev_znr=prev_addr-sb->u.xiafs_sb.s_firstdatazone+1;
-    tmp=get_free_zbit(sb, prev_znr);
-    if (!tmp)
-        return 0;
-    tmp += sb->u.xiafs_sb.s_firstdatazone -1;
-    if (!(bh = getblk(sb->s_dev, tmp, XIAFS_ZSIZE(sb)))) {
-        printk("XIA-FS: I/O error (%s %d)\n", WHERE_ERR);
-	return 0;
-    }
-    if (bh->b_count != 1) {
-        printk(INTERN_ERR);
-	return 0;
-    }
-    clear_buf(bh);
-    mark_buffer_uptodate(bh, 1);
-    mark_buffer_dirty(bh, 1);
-    brelse(bh);
-    return tmp;
-}
-
-void xiafs_free_inode(struct inode * inode)
-{
-    struct buffer_head * bh;
-    struct super_block * sb;
-    unsigned long ino;
-
-    if (!inode)
-        return;
-    if (!inode->i_dev || inode->i_count!=1
-	|| inode->i_nlink || !inode->i_sb || inode->i_ino < 3
-	|| inode->i_ino > inode->i_sb->u.xiafs_sb.s_ninodes) {
-        printk("XIA-FS: bad inode (%s %d)\n", WHERE_ERR);
-	return;
-    }
-    sb = inode->i_sb;
-    ino = inode->i_ino;
-    bh = get_imap_zone(sb, ino, NULL);
-    if (!bh)
-	return;
-    clear_inode(inode);
-    if (!clear_bit(ino & (XIAFS_BITS_PER_Z(sb)-1), bh->b_data))
-        printk("XIA-FS: dev %s"
-	       "inode bit %ld (0x%lx) already cleared (%s %d)\n",
-	       kdevname(inode->i_dev), ino, ino, WHERE_ERR);
-    mark_buffer_dirty(bh, 1);
-    xiafs_unlock_super(sb, sb->u.xiafs_sb.s_imap_cached);
-}
-
-struct inode * xiafs_new_inode(struct inode * dir)
-{
-    struct super_block * sb;
-    struct inode * inode;
-    ino_t tmp;
-
-    sb = dir->i_sb;
-    if (!dir || !(inode = get_empty_inode()))
-        return NULL;
-    inode->i_sb = sb;
-    inode->i_flags = inode->i_sb->s_flags;
-
-    tmp=get_free_ibit(sb, dir->i_ino); 
-    if (!tmp) {
-        iput(inode);
-	return NULL;
-    }
-    inode->i_count = 1;
-    inode->i_nlink = 1;
-    inode->i_dev = sb->s_dev;
-    inode->i_uid = current->fsuid;
-    inode->i_gid = (dir->i_mode & S_ISGID) ? dir->i_gid : current->fsgid;
-    inode->i_dirt = 1;
-    inode->i_ino = tmp;
-    inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
-    inode->i_op = NULL;
-    inode->i_blocks = 0;
-    inode->i_blksize = XIAFS_ZSIZE(inode->i_sb);
-    insert_inode_hash(inode);
-    return inode;
-}
-
-static int nibblemap[] = { 0,1,1,2,1,2,2,3,1,2,2,3,2,3,3,4 };
-
-static u_long count_zone(struct buffer_head * bh)
-{
-    int i, tmp;
-    u_long sum;
-
-    sum=0;
-    for (i=bh->b_size; i-- > 0; ) {
-        tmp=bh->b_data[i];
-        sum += nibblemap[tmp & 0xf] + nibblemap[(tmp & 0xff) >> 4];
-    }
-    return sum;
-} 
-
-unsigned long xiafs_count_free_inodes(struct super_block *sb)
-{
-    struct buffer_head * bh;
-    int izones, i, not_que;
-    u_long sum;
-
-    sum=0;
-    izones=sb->u.xiafs_sb.s_imap_zones;
-    for (i=0; i < izones; i++) {
-        bh=get_imap_zone(sb, i << XIAFS_BITS_PER_Z_BITS(sb), &not_que);
-	if (bh) {
-	    sum += count_zone(bh);
-	    xiafs_unlock_super(sb, sb->u.xiafs_sb.s_imap_cached);
-	}
-    }
-    i=izones << XIAFS_BITS_PER_Z_BITS(sb);
-    return i - sum;
-}
-
-unsigned long xiafs_count_free_zones(struct super_block *sb)
-{
-    struct buffer_head * bh;
-    int zzones, i, not_que;
-    u_long sum;
-
-    sum=0;
-    zzones=sb->u.xiafs_sb.s_zmap_zones;
-    for (i=0; i < zzones; i++) {
-        bh=get_zmap_zone(sb, i << XIAFS_BITS_PER_Z_BITS(sb), &not_que);
-	if (bh) {
-	    sum += count_zone(bh);
-	    xiafs_unlock_super(sb, sb->u.xiafs_sb.s_zmap_cached);
-	}
-    }
-    i=zzones << XIAFS_BITS_PER_Z_BITS(sb);
-    return i - sum;
-}