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

• Lines: 257
• Date: Thu Jan 1 02:00:00 1970
• Orig file: v2.1.20/linux/fs/xiafs/file.c
• Orig date: Tue Oct 29 19:58:46 1996

diff -u --recursive --new-file v2.1.20/linux/fs/xiafs/file.c linux/fs/xiafs/file.c
@@ -1,256 +0,0 @@
-/*
- *  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/uaccess.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 long xiafs_file_read(struct inode *, struct file *, char *, unsigned long);
-static long xiafs_file_write(struct inode *, struct file *, const char *, unsigned long);
-
-/*
- * 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 long
-xiafs_file_read(struct inode * inode, struct file * filp, char * buf, unsigned long 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) {
-	        copy_to_user(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 long
-xiafs_file_write(struct inode * inode, struct file * filp, const char * buf, unsigned long 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;
-	copy_from_user(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;
-}