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[/] [or1k/] [trunk/] [rc203soc/] [sw/] [uClinux/] [fs/] [xiafs/] [file.c] - Blame information for rev 1777

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/*
 *  linux/fs/xiafs/file.c
 *
 *  Copyright (C) Q. Frank Xia, 1993.
 *
 *  Based on Linus' minix/file.c
 *  Copyright (C) Linus Torvalds, 1991, 1992.
 *
 *  This software may be redistributed per Linux Copyright.
 */
 
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/xia_fs.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/fcntl.h>
#include <linux/stat.h>
#include <linux/locks.h>
#include <linux/pagemap.h>
 
#include <asm/segment.h>
#include <asm/system.h>
 
#include "xiafs_mac.h"
 
#define NBUF    32
 
#define MIN(a,b) (((a)<(b))?(a):(b))
#define MAX(a,b) (((a)>(b))?(a):(b))
 
static int xiafs_file_read(struct inode *, struct file *, char *, int);
static int xiafs_file_write(struct inode *, struct file *, const char *, int);
 
/*
 * We have mostly NULL's here: the current defaults are ok for
 * the xiafs filesystem.
 */
static struct file_operations xiafs_file_operations = {
    NULL,                       /* lseek - default */
    xiafs_file_read,            /* read */
    xiafs_file_write,           /* write */
    NULL,                       /* readdir - bad */
    NULL,                       /* select - default */
    NULL,                       /* ioctl - default */
    generic_file_mmap,          /* mmap */
    NULL,                       /* no special open is needed */
    NULL,                       /* release */
    xiafs_sync_file             /* fsync */
};
 
struct inode_operations xiafs_file_inode_operations = {
    &xiafs_file_operations,     /* default file operations */
    NULL,                       /* create */
    NULL,                       /* lookup */
    NULL,                       /* link */
    NULL,                       /* unlink */
    NULL,                       /* symlink */
    NULL,                       /* mkdir */
    NULL,                       /* rmdir */
    NULL,                       /* mknod */
    NULL,                       /* rename */
    NULL,                       /* readlink */
    NULL,                       /* follow_link */
    generic_readpage,           /* readpage */
    NULL,                       /* writepage */
    xiafs_bmap,                 /* bmap */
    xiafs_truncate,             /* truncate */
    NULL                        /* permission */
};
 
static int
xiafs_file_read(struct inode * inode, struct file * filp, char * buf, int count)
{
    int read, left, chars;
    int zone_nr, zones, f_zones, offset;
    int bhrequest, uptodate;
    struct buffer_head ** bhb, ** bhe;
    struct buffer_head * bhreq[NBUF];
    struct buffer_head * buflist[NBUF];
 
    if (!inode) {
        printk("XIA-FS: inode = NULL (%s %d)\n", WHERE_ERR);
        return -EINVAL;
    }
    if (!S_ISREG(inode->i_mode)) {
        printk("XIA-FS: mode != regular (%s %d)\n", WHERE_ERR);
        return -EINVAL;
    }
    offset = filp->f_pos;
    left = inode->i_size - offset;
    if (left > count)
        left = count;
    if (left <= 0)
        return 0;
    read = 0;
    zone_nr = offset >> XIAFS_ZSIZE_BITS(inode->i_sb);
    offset &= XIAFS_ZSIZE(inode->i_sb) -1 ;
    f_zones =(inode->i_size+XIAFS_ZSIZE(inode->i_sb)-1)>>XIAFS_ZSIZE_BITS(inode->i_sb);
    zones = (left+offset+XIAFS_ZSIZE(inode->i_sb)-1) >> XIAFS_ZSIZE_BITS(inode->i_sb);
    bhb = bhe = buflist;
    if (filp->f_reada) {
        if(zones < read_ahead[MAJOR(inode->i_dev)] >> (1+XIAFS_ZSHIFT(inode->i_sb)))
          zones = read_ahead[MAJOR(inode->i_dev)] >> (1+XIAFS_ZSHIFT(inode->i_sb));
        if (zone_nr + zones > f_zones)
            zones = f_zones - zone_nr;
    }
 
    /* We do this in a two stage process.  We first try to request
       as many blocks as we can, then we wait for the first one to
       complete, and then we try to wrap up as many as are actually
       done.  This routine is rather generic, in that it can be used
       in a filesystem by substituting the appropriate function in
       for getblk.
 
       This routine is optimized to make maximum use of the various
       buffers and caches. */
 
    do {
        bhrequest = 0;
        uptodate = 1;
        while (zones--) {
            *bhb = xiafs_getblk(inode, zone_nr++, 0);
            if (*bhb && !buffer_uptodate(*bhb)) {
                uptodate = 0;
                bhreq[bhrequest++] = *bhb;
            }
 
            if (++bhb == &buflist[NBUF])
                bhb = buflist;
 
            /* If the block we have on hand is uptodate, go ahead
               and complete processing. */
            if (uptodate)
                break;
            if (bhb == bhe)
                break;
        }
 
        /* Now request them all */
        if (bhrequest)
            ll_rw_block(READ, bhrequest, bhreq);
 
        do { /* Finish off all I/O that has actually completed */
            if (*bhe) {
                wait_on_buffer(*bhe);
                if (!buffer_uptodate(*bhe)) {   /* read error? */
                    brelse(*bhe);
                    if (++bhe == &buflist[NBUF])
                      bhe = buflist;
                    left = 0;
                    break;
                }
            }
            if (left < XIAFS_ZSIZE(inode->i_sb) - offset)
                chars = left;
            else
                chars = XIAFS_ZSIZE(inode->i_sb) - offset;
            filp->f_pos += chars;
            left -= chars;
            read += chars;
            if (*bhe) {
                memcpy_tofs(buf,offset+(*bhe)->b_data,chars);
                brelse(*bhe);
                buf += chars;
            } else {
                while (chars-->0)
                    put_user(0,buf++);
            }
            offset = 0;
            if (++bhe == &buflist[NBUF])
                bhe = buflist;
        } while (left > 0 && bhe != bhb && (!*bhe || !buffer_locked(*bhe)));
    } while (left > 0);
 
/* Release the read-ahead blocks */
    while (bhe != bhb) {
        brelse(*bhe);
        if (++bhe == &buflist[NBUF])
            bhe = buflist;
    };
    if (!read)
        return -EIO;
    filp->f_reada = 1;
    if (!IS_RDONLY (inode)) {
        inode->i_atime = CURRENT_TIME;
        inode->i_dirt = 1;
    }
    return read;
}
 
static int
xiafs_file_write(struct inode * inode, struct file * filp, const char * buf, int count)
{
    off_t pos;
    int written, c;
    struct buffer_head * bh;
    char * cp;
 
    if (!inode) {
        printk("XIA-FS: inode = NULL (%s %d)\n", WHERE_ERR);
        return -EINVAL;
    }
    if (!S_ISREG(inode->i_mode)) {
        printk("XIA-FS: mode != regular (%s %d)\n", WHERE_ERR);
        return -EINVAL;
    }
/*
 * ok, append may not work when many processes are writing at the same time
 * but so what. That way leads to madness anyway.
 */
    if (filp->f_flags & O_APPEND)
        pos = inode->i_size;
    else
        pos = filp->f_pos;
    written = 0;
    while (written < count) {
        bh = xiafs_getblk(inode, pos >> XIAFS_ZSIZE_BITS(inode->i_sb), 1);
        if (!bh) {
            if (!written)
                written = -ENOSPC;
            break;
        }
        c = XIAFS_ZSIZE(inode->i_sb) - (pos & (XIAFS_ZSIZE(inode->i_sb) - 1));
        if (c > count-written)
            c = count-written;
        if (c != XIAFS_ZSIZE(inode->i_sb) && !buffer_uptodate(bh)) {
            ll_rw_block(READ, 1, &bh);
            wait_on_buffer(bh);
            if (!buffer_uptodate(bh)) {
                brelse(bh);
                if (!written)
                    written = -EIO;
                break;
            }
        }
        cp = (pos & (XIAFS_ZSIZE(inode->i_sb)-1)) + bh->b_data;
        memcpy_fromfs(cp,buf,c);
        update_vm_cache(inode,pos,cp,c);
        pos += c;
        if (pos > inode->i_size) {
            inode->i_size = pos;
            inode->i_dirt = 1;
        }
        written += c;
        buf += c;
        mark_buffer_uptodate(bh, 1);
        mark_buffer_dirty(bh, 0);
        brelse(bh);
    }
    inode->i_mtime = inode->i_ctime = CURRENT_TIME;
    filp->f_pos = pos;
    inode->i_dirt = 1;
 
    return written;
}

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[/] [or1k/] [trunk/] [rc203soc/] [sw/] [uClinux/] [fs/] [xiafs/] [file.c] - Blame information for rev 1777

Line No.	Rev	Author	Line
1	1628	jcastillo	`/*`
2			`* linux/fs/xiafs/file.c`
3			`*`
4			`* Copyright (C) Q. Frank Xia, 1993.`
5			`*`
6			`* Based on Linus' minix/file.c`
7			`* Copyright (C) Linus Torvalds, 1991, 1992.`
8			`*`
9			`* This software may be redistributed per Linux Copyright.`
10			`*/`
11
12			`#include <linux/sched.h>`
13			`#include <linux/fs.h>`
14			`#include <linux/xia_fs.h>`
15			`#include <linux/kernel.h>`
16			`#include <linux/errno.h>`
17			`#include <linux/fcntl.h>`
18			`#include <linux/stat.h>`
19			`#include <linux/locks.h>`
20			`#include <linux/pagemap.h>`
21
22			`#include <asm/segment.h>`
23			`#include <asm/system.h>`
24
25			`#include "xiafs_mac.h"`
26
27			`#define NBUF 32`
28
29			`#define MIN(a,b) (((a)<(b))?(a):(b))`
30			`#define MAX(a,b) (((a)>(b))?(a):(b))`
31
32			`static int xiafs_file_read(struct inode , struct file , char *, int);`
33			`static int xiafs_file_write(struct inode , struct file , const char *, int);`
34
35			`/*`
36			`* We have mostly NULL's here: the current defaults are ok for`
37			`* the xiafs filesystem.`
38			`*/`
39			`static struct file_operations xiafs_file_operations = {`
40			`NULL, /* lseek - default */`
41			`xiafs_file_read, /* read */`
42			`xiafs_file_write, /* write */`
43			`NULL, /* readdir - bad */`
44			`NULL, /* select - default */`
45			`NULL, /* ioctl - default */`
46			`generic_file_mmap, /* mmap */`
47			`NULL, /* no special open is needed */`
48			`NULL, /* release */`
49			`xiafs_sync_file /* fsync */`
50			`};`
51
52			`struct inode_operations xiafs_file_inode_operations = {`
53			`&xiafs_file_operations, /* default file operations */`
54			`NULL, /* create */`
55			`NULL, /* lookup */`
56			`NULL, /* link */`
57			`NULL, /* unlink */`
58			`NULL, /* symlink */`
59			`NULL, /* mkdir */`
60			`NULL, /* rmdir */`
61			`NULL, /* mknod */`
62			`NULL, /* rename */`
63			`NULL, /* readlink */`
64			`NULL, /* follow_link */`
65			`generic_readpage, /* readpage */`
66			`NULL, /* writepage */`
67			`xiafs_bmap, /* bmap */`
68			`xiafs_truncate, /* truncate */`
69			`NULL /* permission */`
70			`};`
71
72			`static int`
73			`xiafs_file_read(struct inode * inode, struct file * filp, char * buf, int count)`
74			`{`
75			`int read, left, chars;`
76			`int zone_nr, zones, f_zones, offset;`
77			`int bhrequest, uptodate;`
78			`struct buffer_head bhb, bhe;`
79			`struct buffer_head * bhreq[NBUF];`
80			`struct buffer_head * buflist[NBUF];`
81
82			`if (!inode) {`
83			`printk("XIA-FS: inode = NULL (%s %d)\n", WHERE_ERR);`
84			`return -EINVAL;`
85			`}`
86			`if (!S_ISREG(inode->i_mode)) {`
87			`printk("XIA-FS: mode != regular (%s %d)\n", WHERE_ERR);`
88			`return -EINVAL;`
89			`}`
90			`offset = filp->f_pos;`
91			`left = inode->i_size - offset;`
92			`if (left > count)`
93			`left = count;`
94			`if (left <= 0)`
95			`return 0;`
96			`read = 0;`
97			`zone_nr = offset >> XIAFS_ZSIZE_BITS(inode->i_sb);`
98			`offset &= XIAFS_ZSIZE(inode->i_sb) -1 ;`
99			`f_zones =(inode->i_size+XIAFS_ZSIZE(inode->i_sb)-1)>>XIAFS_ZSIZE_BITS(inode->i_sb);`
100			`zones = (left+offset+XIAFS_ZSIZE(inode->i_sb)-1) >> XIAFS_ZSIZE_BITS(inode->i_sb);`
101			`bhb = bhe = buflist;`
102			`if (filp->f_reada) {`
103			`if(zones < read_ahead[MAJOR(inode->i_dev)] >> (1+XIAFS_ZSHIFT(inode->i_sb)))`
104			`zones = read_ahead[MAJOR(inode->i_dev)] >> (1+XIAFS_ZSHIFT(inode->i_sb));`
105			`if (zone_nr + zones > f_zones)`
106			`zones = f_zones - zone_nr;`
107			`}`
108
109			`/* We do this in a two stage process. We first try to request`
110			`as many blocks as we can, then we wait for the first one to`
111			`complete, and then we try to wrap up as many as are actually`
112			`done. This routine is rather generic, in that it can be used`
113			`in a filesystem by substituting the appropriate function in`
114			`for getblk.`
115
116			`This routine is optimized to make maximum use of the various`
117			`buffers and caches. */`
118
119			`do {`
120			`bhrequest = 0;`
121			`uptodate = 1;`
122			`while (zones--) {`
123			`*bhb = xiafs_getblk(inode, zone_nr++, 0);`
124			`if (bhb && !buffer_uptodate(bhb)) {`
125			`uptodate = 0;`
126			`bhreq[bhrequest++] = *bhb;`
127			`}`
128
129			`if (++bhb == &buflist[NBUF])`
130			`bhb = buflist;`
131
132			`/* If the block we have on hand is uptodate, go ahead`
133			`and complete processing. */`
134			`if (uptodate)`
135			`break;`
136			`if (bhb == bhe)`
137			`break;`
138			`}`
139
140			`/* Now request them all */`
141			`if (bhrequest)`
142			`ll_rw_block(READ, bhrequest, bhreq);`
143
144			`do { /* Finish off all I/O that has actually completed */`
145			`if (*bhe) {`
146			`wait_on_buffer(*bhe);`
147			`if (!buffer_uptodate(bhe)) { / read error? */`
148			`brelse(*bhe);`
149			`if (++bhe == &buflist[NBUF])`
150			`bhe = buflist;`
151			`left = 0;`
152			`break;`
153			`}`
154			`}`
155			`if (left < XIAFS_ZSIZE(inode->i_sb) - offset)`
156			`chars = left;`
157			`else`
158			`chars = XIAFS_ZSIZE(inode->i_sb) - offset;`
159			`filp->f_pos += chars;`
160			`left -= chars;`
161			`read += chars;`
162			`if (*bhe) {`
163			`memcpy_tofs(buf,offset+(*bhe)->b_data,chars);`
164			`brelse(*bhe);`
165			`buf += chars;`
166			`} else {`
167			`while (chars-->0)`
168			`put_user(0,buf++);`
169			`}`
170			`offset = 0;`
171			`if (++bhe == &buflist[NBUF])`
172			`bhe = buflist;`
173			`} while (left > 0 && bhe != bhb && (!bhe \|\| !buffer_locked(bhe)));`
174			`} while (left > 0);`
175
176			`/* Release the read-ahead blocks */`
177			`while (bhe != bhb) {`
178			`brelse(*bhe);`
179			`if (++bhe == &buflist[NBUF])`
180			`bhe = buflist;`
181			`};`
182			`if (!read)`
183			`return -EIO;`
184			`filp->f_reada = 1;`
185			`if (!IS_RDONLY (inode)) {`
186			`inode->i_atime = CURRENT_TIME;`
187			`inode->i_dirt = 1;`
188			`}`
189			`return read;`
190			`}`
191
192			`static int`
193			`xiafs_file_write(struct inode * inode, struct file * filp, const char * buf, int count)`
194			`{`
195			`off_t pos;`
196			`int written, c;`
197			`struct buffer_head * bh;`
198			`char * cp;`
199
200			`if (!inode) {`
201			`printk("XIA-FS: inode = NULL (%s %d)\n", WHERE_ERR);`
202			`return -EINVAL;`
203			`}`
204			`if (!S_ISREG(inode->i_mode)) {`
205			`printk("XIA-FS: mode != regular (%s %d)\n", WHERE_ERR);`
206			`return -EINVAL;`
207			`}`
208			`/*`
209			`* ok, append may not work when many processes are writing at the same time`
210			`* but so what. That way leads to madness anyway.`
211			`*/`
212			`if (filp->f_flags & O_APPEND)`
213			`pos = inode->i_size;`
214			`else`
215			`pos = filp->f_pos;`
216			`written = 0;`
217			`while (written < count) {`
218			`bh = xiafs_getblk(inode, pos >> XIAFS_ZSIZE_BITS(inode->i_sb), 1);`
219			`if (!bh) {`
220			`if (!written)`
221			`written = -ENOSPC;`
222			`break;`
223			`}`
224			`c = XIAFS_ZSIZE(inode->i_sb) - (pos & (XIAFS_ZSIZE(inode->i_sb) - 1));`
225			`if (c > count-written)`
226			`c = count-written;`
227			`if (c != XIAFS_ZSIZE(inode->i_sb) && !buffer_uptodate(bh)) {`
228			`ll_rw_block(READ, 1, &bh);`
229			`wait_on_buffer(bh);`
230			`if (!buffer_uptodate(bh)) {`
231			`brelse(bh);`
232			`if (!written)`
233			`written = -EIO;`
234			`break;`
235			`}`
236			`}`
237			`cp = (pos & (XIAFS_ZSIZE(inode->i_sb)-1)) + bh->b_data;`
238			`memcpy_fromfs(cp,buf,c);`
239			`update_vm_cache(inode,pos,cp,c);`
240			`pos += c;`
241			`if (pos > inode->i_size) {`
242			`inode->i_size = pos;`
243			`inode->i_dirt = 1;`
244			`}`
245			`written += c;`
246			`buf += c;`
247			`mark_buffer_uptodate(bh, 1);`
248			`mark_buffer_dirty(bh, 0);`
249			`brelse(bh);`
250			`}`
251			`inode->i_mtime = inode->i_ctime = CURRENT_TIME;`
252			`filp->f_pos = pos;`
253			`inode->i_dirt = 1;`
254
255			`return written;`
256			`}`