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[/] [or1k/] [trunk/] [rc203soc/] [sw/] [uClinux/] [fs/] [minix/] [bitmap.c] - Blame information for rev 1628

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/*
 *  linux/fs/minix/bitmap.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */
 
/* bitmap.c contains the code that handles the inode and block bitmaps */
 
#include <linux/sched.h>
#include <linux/minix_fs.h>
#include <linux/stat.h>
#include <linux/kernel.h>
#include <linux/string.h>
 
#include <asm/bitops.h>
 
static int nibblemap[] = { 4,3,3,2,3,2,2,1,3,2,2,1,2,1,1,0 };
 
static unsigned long count_free(struct buffer_head *map[], unsigned numblocks)
{
        unsigned i, j, sum = 0;
        struct buffer_head *bh;
 
        for (i=0; i<numblocks; i++) {
                if (!(bh=map[i]))
                        return(0);
                for (j=0; j<BLOCK_SIZE; j++)
                        sum += nibblemap[bh->b_data[j] & 0xf]
                                + nibblemap[(bh->b_data[j]>>4)&0xf];
        }
        return(sum);
}
 
void minix_free_block(struct super_block * sb, int block)
{
        struct buffer_head * bh;
        unsigned int bit,zone;
 
        if (!sb) {
                printk("trying to free block on nonexistent device\n");
                return;
        }
        if (block < sb->u.minix_sb.s_firstdatazone ||
            block >= sb->u.minix_sb.s_nzones) {
                printk("trying to free block not in datazone\n");
                return;
        }
        bh = get_hash_table(sb->s_dev,block,BLOCK_SIZE);
        if (bh)
                clear_bit(BH_Dirty, &bh->b_state);
        brelse(bh);
        zone = block - sb->u.minix_sb.s_firstdatazone + 1;
        bit = zone & 8191;
        zone >>= 13;
        bh = sb->u.minix_sb.s_zmap[zone];
        if (!bh) {
                printk("minix_free_block: nonexistent bitmap buffer\n");
                return;
        }
        if (!clear_bit(bit,bh->b_data))
                printk("free_block (%s:%d): bit already cleared\n",
                       kdevname(sb->s_dev), block);
        mark_buffer_dirty(bh, 1);
        return;
}
 
int minix_new_block(struct super_block * sb)
{
        struct buffer_head * bh;
        int i,j;
 
        if (!sb) {
                printk("trying to get new block from nonexistent device\n");
                return 0;
        }
repeat:
        j = 8192;
        for (i=0 ; i<64 ; i++)
                if ((bh=sb->u.minix_sb.s_zmap[i]) != NULL)
                        if ((j=find_first_zero_bit(bh->b_data, 8192)) < 8192)
                                break;
        if (i>=64 || !bh || j>=8192)
                return 0;
        if (set_bit(j,bh->b_data)) {
                printk("new_block: bit already set");
                goto repeat;
        }
        mark_buffer_dirty(bh, 1);
        j += i*8192 + sb->u.minix_sb.s_firstdatazone-1;
        if (j < sb->u.minix_sb.s_firstdatazone ||
            j >= sb->u.minix_sb.s_nzones)
                return 0;
        if (!(bh = getblk(sb->s_dev,j,BLOCK_SIZE))) {
                printk("new_block: cannot get block");
                return 0;
        }
        memset(bh->b_data, 0, BLOCK_SIZE);
        mark_buffer_uptodate(bh, 1);
        mark_buffer_dirty(bh, 1);
        brelse(bh);
        return j;
}
 
unsigned long minix_count_free_blocks(struct super_block *sb)
{
        return (count_free(sb->u.minix_sb.s_zmap,sb->u.minix_sb.s_zmap_blocks)
                 << sb->u.minix_sb.s_log_zone_size);
}
 
static struct buffer_head *V1_minix_clear_inode(struct inode *inode)
{
        struct buffer_head *bh;
        struct minix_inode *raw_inode;
        int ino, block;
 
        ino = inode->i_ino;
        if (!ino || ino >= inode->i_sb->u.minix_sb.s_ninodes) {
                printk("Bad inode number on dev %s: %d is out of range\n",
                       kdevname(inode->i_dev), ino);
                return 0;
        }
        block = (2 + inode->i_sb->u.minix_sb.s_imap_blocks +
                 inode->i_sb->u.minix_sb.s_zmap_blocks +
                 (ino - 1) / MINIX_INODES_PER_BLOCK);
        bh = bread(inode->i_dev, block, BLOCK_SIZE);
        if (!bh) {
                printk("unable to read i-node block\n");
                return 0;
        }
        raw_inode = ((struct minix_inode *)bh->b_data +
                     (ino - 1) % MINIX_INODES_PER_BLOCK);
        raw_inode->i_nlinks = 0;
        raw_inode->i_mode = 0;
        mark_buffer_dirty(bh, 1);
        return bh;
}
 
static struct buffer_head *V2_minix_clear_inode(struct inode *inode)
{
        struct buffer_head *bh;
        struct minix2_inode *raw_inode;
        int ino, block;
 
        ino = inode->i_ino;
        if (!ino || ino >= inode->i_sb->u.minix_sb.s_ninodes) {
                printk("Bad inode number on dev %s: %d is out of range\n",
                       kdevname(inode->i_dev), ino);
                return 0;
        }
        block = (2 + inode->i_sb->u.minix_sb.s_imap_blocks +
                 inode->i_sb->u.minix_sb.s_zmap_blocks +
                 (ino - 1) / MINIX2_INODES_PER_BLOCK);
        bh = bread(inode->i_dev, block, BLOCK_SIZE);
        if (!bh) {
                printk("unable to read i-node block\n");
                return 0;
        }
        raw_inode = ((struct minix2_inode *) bh->b_data +
                     (ino - 1) % MINIX2_INODES_PER_BLOCK);
        raw_inode->i_nlinks = 0;
        raw_inode->i_mode = 0;
        mark_buffer_dirty(bh, 1);
        return bh;
}
 
/* Clear the link count and mode of a deleted inode on disk. */
 
static void minix_clear_inode(struct inode *inode)
{
        struct buffer_head *bh;
        if (INODE_VERSION(inode) == MINIX_V1)
                bh = V1_minix_clear_inode(inode);
        else
                bh = V2_minix_clear_inode(inode);
        brelse (bh);
}
 
void minix_free_inode(struct inode * inode)
{
        struct buffer_head * bh;
        unsigned long ino;
 
        if (!inode)
                return;
        if (!inode->i_dev) {
                printk("free_inode: inode has no device\n");
                return;
        }
        if (inode->i_count != 1) {
                printk("free_inode: inode has count=%ld\n",inode->i_count);
                return;
        }
        if (inode->i_nlink) {
                printk("free_inode: inode has nlink=%d\n",inode->i_nlink);
                return;
        }
        if (!inode->i_sb) {
                printk("free_inode: inode on nonexistent device\n");
                return;
        }
        if (inode->i_ino < 1 || inode->i_ino >= inode->i_sb->u.minix_sb.s_ninodes) {
                printk("free_inode: inode 0 or nonexistent inode\n");
                return;
        }
        ino = inode->i_ino;
        if (!(bh=inode->i_sb->u.minix_sb.s_imap[ino >> 13])) {
                printk("free_inode: nonexistent imap in superblock\n");
                return;
        }
        minix_clear_inode(inode);
        clear_inode(inode);
        if (!clear_bit(ino & 8191, bh->b_data))
                printk("free_inode: bit %lu already cleared.\n",ino);
        mark_buffer_dirty(bh, 1);
}
 
struct inode * minix_new_inode(const struct inode * dir)
{
        struct super_block * sb;
        struct inode * inode;
        struct buffer_head * bh;
        int i,j;
 
        if (!dir || !(inode = get_empty_inode()))
                return NULL;
        sb = dir->i_sb;
        inode->i_sb = sb;
        inode->i_flags = inode->i_sb->s_flags;
        j = 8192;
        for (i=0 ; i<8 ; i++)
                if ((bh = inode->i_sb->u.minix_sb.s_imap[i]) != NULL)
                        if ((j=find_first_zero_bit(bh->b_data, 8192)) < 8192)
                                break;
        if (!bh || j >= 8192) {
                iput(inode);
                return NULL;
        }
        if (set_bit(j,bh->b_data)) {    /* shouldn't happen */
                printk("new_inode: bit already set");
                iput(inode);
                return NULL;
        }
        mark_buffer_dirty(bh, 1);
        j += i*8192;
        if (!j || j >= inode->i_sb->u.minix_sb.s_ninodes) {
                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 = j;
        inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
        inode->i_op = NULL;
        inode->i_blocks = inode->i_blksize = 0;
        insert_inode_hash(inode);
        return inode;
}
 
unsigned long minix_count_free_inodes(struct super_block *sb)
{
        return count_free(sb->u.minix_sb.s_imap,sb->u.minix_sb.s_imap_blocks);
}

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[/] [or1k/] [trunk/] [rc203soc/] [sw/] [uClinux/] [fs/] [minix/] [bitmap.c] - Blame information for rev 1628

Line No.	Rev	Author	Line
1	1628	jcastillo	`/*`
2			`* linux/fs/minix/bitmap.c`
3			`*`
4			`* Copyright (C) 1991, 1992 Linus Torvalds`
5			`*/`
6
7			`/* bitmap.c contains the code that handles the inode and block bitmaps */`
8
9			`#include <linux/sched.h>`
10			`#include <linux/minix_fs.h>`
11			`#include <linux/stat.h>`
12			`#include <linux/kernel.h>`
13			`#include <linux/string.h>`
14
15			`#include <asm/bitops.h>`
16
17			`static int nibblemap[] = { 4,3,3,2,3,2,2,1,3,2,2,1,2,1,1,0 };`
18
19			`static unsigned long count_free(struct buffer_head *map[], unsigned numblocks)`
20			`{`
21			`unsigned i, j, sum = 0;`
22			`struct buffer_head *bh;`
23
24			`for (i=0; i<numblocks; i++) {`
25			`if (!(bh=map[i]))`
26			`return(0);`
27			`for (j=0; j<BLOCK_SIZE; j++)`
28			`sum += nibblemap[bh->b_data[j] & 0xf]`
29			`+ nibblemap[(bh->b_data[j]>>4)&0xf];`
30			`}`
31			`return(sum);`
32			`}`
33
34			`void minix_free_block(struct super_block * sb, int block)`
35			`{`
36			`struct buffer_head * bh;`
37			`unsigned int bit,zone;`
38
39			`if (!sb) {`
40			`printk("trying to free block on nonexistent device\n");`
41			`return;`
42			`}`
43			`if (block < sb->u.minix_sb.s_firstdatazone \|\|`
44			`block >= sb->u.minix_sb.s_nzones) {`
45			`printk("trying to free block not in datazone\n");`
46			`return;`
47			`}`
48			`bh = get_hash_table(sb->s_dev,block,BLOCK_SIZE);`
49			`if (bh)`
50			`clear_bit(BH_Dirty, &bh->b_state);`
51			`brelse(bh);`
52			`zone = block - sb->u.minix_sb.s_firstdatazone + 1;`
53			`bit = zone & 8191;`
54			`zone >>= 13;`
55			`bh = sb->u.minix_sb.s_zmap[zone];`
56			`if (!bh) {`
57			`printk("minix_free_block: nonexistent bitmap buffer\n");`
58			`return;`
59			`}`
60			`if (!clear_bit(bit,bh->b_data))`
61			`printk("free_block (%s:%d): bit already cleared\n",`
62			`kdevname(sb->s_dev), block);`
63			`mark_buffer_dirty(bh, 1);`
64			`return;`
65			`}`
66
67			`int minix_new_block(struct super_block * sb)`
68			`{`
69			`struct buffer_head * bh;`
70			`int i,j;`
71
72			`if (!sb) {`
73			`printk("trying to get new block from nonexistent device\n");`
74			`return 0;`
75			`}`
76			`repeat:`
77			`j = 8192;`
78			`for (i=0 ; i<64 ; i++)`
79			`if ((bh=sb->u.minix_sb.s_zmap[i]) != NULL)`
80			`if ((j=find_first_zero_bit(bh->b_data, 8192)) < 8192)`
81			`break;`
82			`if (i>=64 \|\| !bh \|\| j>=8192)`
83			`return 0;`
84			`if (set_bit(j,bh->b_data)) {`
85			`printk("new_block: bit already set");`
86			`goto repeat;`
87			`}`
88			`mark_buffer_dirty(bh, 1);`
89			`j += i*8192 + sb->u.minix_sb.s_firstdatazone-1;`
90			`if (j < sb->u.minix_sb.s_firstdatazone \|\|`
91			`j >= sb->u.minix_sb.s_nzones)`
92			`return 0;`
93			`if (!(bh = getblk(sb->s_dev,j,BLOCK_SIZE))) {`
94			`printk("new_block: cannot get block");`
95			`return 0;`
96			`}`
97			`memset(bh->b_data, 0, BLOCK_SIZE);`
98			`mark_buffer_uptodate(bh, 1);`
99			`mark_buffer_dirty(bh, 1);`
100			`brelse(bh);`
101			`return j;`
102			`}`
103
104			`unsigned long minix_count_free_blocks(struct super_block *sb)`
105			`{`
106			`return (count_free(sb->u.minix_sb.s_zmap,sb->u.minix_sb.s_zmap_blocks)`
107			`<< sb->u.minix_sb.s_log_zone_size);`
108			`}`
109
110			`static struct buffer_head V1_minix_clear_inode(struct inode inode)`
111			`{`
112			`struct buffer_head *bh;`
113			`struct minix_inode *raw_inode;`
114			`int ino, block;`
115
116			`ino = inode->i_ino;`
117			`if (!ino \|\| ino >= inode->i_sb->u.minix_sb.s_ninodes) {`
118			`printk("Bad inode number on dev %s: %d is out of range\n",`
119			`kdevname(inode->i_dev), ino);`
120			`return 0;`
121			`}`
122			`block = (2 + inode->i_sb->u.minix_sb.s_imap_blocks +`
123			`inode->i_sb->u.minix_sb.s_zmap_blocks +`
124			`(ino - 1) / MINIX_INODES_PER_BLOCK);`
125			`bh = bread(inode->i_dev, block, BLOCK_SIZE);`
126			`if (!bh) {`
127			`printk("unable to read i-node block\n");`
128			`return 0;`
129			`}`
130			`raw_inode = ((struct minix_inode *)bh->b_data +`
131			`(ino - 1) % MINIX_INODES_PER_BLOCK);`
132			`raw_inode->i_nlinks = 0;`
133			`raw_inode->i_mode = 0;`
134			`mark_buffer_dirty(bh, 1);`
135			`return bh;`
136			`}`
137
138			`static struct buffer_head V2_minix_clear_inode(struct inode inode)`
139			`{`
140			`struct buffer_head *bh;`
141			`struct minix2_inode *raw_inode;`
142			`int ino, block;`
143
144			`ino = inode->i_ino;`
145			`if (!ino \|\| ino >= inode->i_sb->u.minix_sb.s_ninodes) {`
146			`printk("Bad inode number on dev %s: %d is out of range\n",`
147			`kdevname(inode->i_dev), ino);`
148			`return 0;`
149			`}`
150			`block = (2 + inode->i_sb->u.minix_sb.s_imap_blocks +`
151			`inode->i_sb->u.minix_sb.s_zmap_blocks +`
152			`(ino - 1) / MINIX2_INODES_PER_BLOCK);`
153			`bh = bread(inode->i_dev, block, BLOCK_SIZE);`
154			`if (!bh) {`
155			`printk("unable to read i-node block\n");`
156			`return 0;`
157			`}`
158			`raw_inode = ((struct minix2_inode *) bh->b_data +`
159			`(ino - 1) % MINIX2_INODES_PER_BLOCK);`
160			`raw_inode->i_nlinks = 0;`
161			`raw_inode->i_mode = 0;`
162			`mark_buffer_dirty(bh, 1);`
163			`return bh;`
164			`}`
165
166			`/* Clear the link count and mode of a deleted inode on disk. */`
167
168			`static void minix_clear_inode(struct inode *inode)`
169			`{`
170			`struct buffer_head *bh;`
171			`if (INODE_VERSION(inode) == MINIX_V1)`
172			`bh = V1_minix_clear_inode(inode);`
173			`else`
174			`bh = V2_minix_clear_inode(inode);`
175			`brelse (bh);`
176			`}`
177
178			`void minix_free_inode(struct inode * inode)`
179			`{`
180			`struct buffer_head * bh;`
181			`unsigned long ino;`
182
183			`if (!inode)`
184			`return;`
185			`if (!inode->i_dev) {`
186			`printk("free_inode: inode has no device\n");`
187			`return;`
188			`}`
189			`if (inode->i_count != 1) {`
190			`printk("free_inode: inode has count=%ld\n",inode->i_count);`
191			`return;`
192			`}`
193			`if (inode->i_nlink) {`
194			`printk("free_inode: inode has nlink=%d\n",inode->i_nlink);`
195			`return;`
196			`}`
197			`if (!inode->i_sb) {`
198			`printk("free_inode: inode on nonexistent device\n");`
199			`return;`
200			`}`
201			`if (inode->i_ino < 1 \|\| inode->i_ino >= inode->i_sb->u.minix_sb.s_ninodes) {`
202			`printk("free_inode: inode 0 or nonexistent inode\n");`
203			`return;`
204			`}`
205			`ino = inode->i_ino;`
206			`if (!(bh=inode->i_sb->u.minix_sb.s_imap[ino >> 13])) {`
207			`printk("free_inode: nonexistent imap in superblock\n");`
208			`return;`
209			`}`
210			`minix_clear_inode(inode);`
211			`clear_inode(inode);`
212			`if (!clear_bit(ino & 8191, bh->b_data))`
213			`printk("free_inode: bit %lu already cleared.\n",ino);`
214			`mark_buffer_dirty(bh, 1);`
215			`}`
216
217			`struct inode * minix_new_inode(const struct inode * dir)`
218			`{`
219			`struct super_block * sb;`
220			`struct inode * inode;`
221			`struct buffer_head * bh;`
222			`int i,j;`
223
224			`if (!dir \|\| !(inode = get_empty_inode()))`
225			`return NULL;`
226			`sb = dir->i_sb;`
227			`inode->i_sb = sb;`
228			`inode->i_flags = inode->i_sb->s_flags;`
229			`j = 8192;`
230			`for (i=0 ; i<8 ; i++)`
231			`if ((bh = inode->i_sb->u.minix_sb.s_imap[i]) != NULL)`
232			`if ((j=find_first_zero_bit(bh->b_data, 8192)) < 8192)`
233			`break;`
234			`if (!bh \|\| j >= 8192) {`
235			`iput(inode);`
236			`return NULL;`
237			`}`
238			`if (set_bit(j,bh->b_data)) { /* shouldn't happen */`
239			`printk("new_inode: bit already set");`
240			`iput(inode);`
241			`return NULL;`
242			`}`
243			`mark_buffer_dirty(bh, 1);`
244			`j += i*8192;`
245			`if (!j \|\| j >= inode->i_sb->u.minix_sb.s_ninodes) {`
246			`iput(inode);`
247			`return NULL;`
248			`}`
249			`inode->i_count = 1;`
250			`inode->i_nlink = 1;`
251			`inode->i_dev = sb->s_dev;`
252			`inode->i_uid = current->fsuid;`
253			`inode->i_gid = (dir->i_mode & S_ISGID) ? dir->i_gid : current->fsgid;`
254			`inode->i_dirt = 1;`
255			`inode->i_ino = j;`
256			`inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;`
257			`inode->i_op = NULL;`
258			`inode->i_blocks = inode->i_blksize = 0;`
259			`insert_inode_hash(inode);`
260			`return inode;`
261			`}`
262
263			`unsigned long minix_count_free_inodes(struct super_block *sb)`
264			`{`
265			`return count_free(sb->u.minix_sb.s_imap,sb->u.minix_sb.s_imap_blocks);`
266			`}`