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

• Lines: 265
• Date: Thu Jan 1 02:00:00 1970
• Orig file: v2.1.20/linux/fs/ext/file.c
• Orig date: Tue Oct 29 19:58:20 1996

diff -u --recursive --new-file v2.1.20/linux/fs/ext/file.c linux/fs/ext/file.c
@@ -1,264 +0,0 @@
-/*
- *  linux/fs/ext/file.c
- *
- *  Copyright (C) 1992 Remy Card (card@masi.ibp.fr)
- *
- *  from
- *
- *  linux/fs/minix/file.c
- *
- *  Copyright (C) 1991, 1992 Linus Torvalds
- *
- *  ext regular file handling primitives
- */
-
-#include <asm/uaccess.h>
-#include <asm/system.h>
-
-#include <linux/sched.h>
-#include <linux/ext_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>
-
-#define	NBUF	32
-
-#define MIN(a,b) (((a)<(b))?(a):(b))
-#define MAX(a,b) (((a)>(b))?(a):(b))
-
-#include <linux/fs.h>
-#include <linux/ext_fs.h>
-
-static long ext_file_read(struct inode *, struct file *, char *, unsigned long);
-static long ext_file_write(struct inode *, struct file *, const char *, unsigned long);
-
-/*
- * We have mostly NULL's here: the current defaults are ok for
- * the ext filesystem.
- */
-static struct file_operations ext_file_operations = {
-	NULL,			/* lseek - default */
-	ext_file_read,	/* read */
-	ext_file_write,	/* write */
-	NULL,			/* readdir - bad */
-	NULL,			/* select - default */
-	NULL,			/* ioctl - default */
-	generic_file_mmap,	/* mmap */
-	NULL,			/* no special open is needed */
-	NULL,			/* release */
-	ext_sync_file			/* fsync */
-};
-
-struct inode_operations ext_file_inode_operations = {
-	&ext_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 */
-	ext_bmap,		/* bmap */
-	ext_truncate,		/* truncate */
-	NULL			/* permission */
-};
-
-static long ext_file_read(struct inode * inode, struct file * filp,
-	char * buf, unsigned long count)
-{
-	int read,left,chars;
-	int block, blocks, offset;
-	int bhrequest, uptodate;
-	struct buffer_head ** bhb, ** bhe;
-	struct buffer_head * bhreq[NBUF];
-	struct buffer_head * buflist[NBUF];
-	unsigned int size;
-
-	if (!inode) {
-		printk("ext_file_read: inode = NULL\n");
-		return -EINVAL;
-	}
-	if (!S_ISREG(inode->i_mode)) {
-		printk("ext_file_read: mode = %07o\n",inode->i_mode);
-		return -EINVAL;
-	}
-	offset = filp->f_pos;
-	size = inode->i_size;
-	if (offset > size)
-		left = 0;
-	else
-		left = size - offset;
-	if (left > count)
-		left = count;
-	if (left <= 0)
-		return 0;
-	read = 0;
-	block = offset >> BLOCK_SIZE_BITS;
-	offset &= BLOCK_SIZE-1;
-	size = (size + (BLOCK_SIZE-1)) >> BLOCK_SIZE_BITS;
-	blocks = (left + offset + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
-	bhb = bhe = buflist;
-	if (filp->f_reada) {
-	        if(blocks < read_ahead[MAJOR(inode->i_dev)] / (BLOCK_SIZE >> 9))
-		  blocks = read_ahead[MAJOR(inode->i_dev)] / (BLOCK_SIZE >> 9);
-		if (block + blocks > size)
-			blocks = size - block;
-	}
-
-	/* 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 (blocks) {
-			--blocks;
-			*bhb = ext_getblk(inode, block++, 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 < BLOCK_SIZE - offset)
-				chars = left;
-			else
-				chars = BLOCK_SIZE - 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 ext_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 * p;
-
-	if (!inode) {
-		printk("ext_file_write: inode = NULL\n");
-		return -EINVAL;
-	}
-	if (!S_ISREG(inode->i_mode)) {
-		printk("ext_file_write: mode = %07o\n",inode->i_mode);
-		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 = ext_getblk(inode,pos/BLOCK_SIZE,1);
-		if (!bh) {
-			if (!written)
-				written = -ENOSPC;
-			break;
-		}
-		c = BLOCK_SIZE - (pos % BLOCK_SIZE);
-		if (c > count-written)
-			c = count-written;
-		if (c != BLOCK_SIZE && !buffer_uptodate(bh)) {
-			ll_rw_block(READ, 1, &bh);
-			wait_on_buffer(bh);
-			if (!buffer_uptodate(bh)) {
-				brelse(bh);
-				if (!written)
-					written = -EIO;
-				break;
-			}
-		}
-		p = (pos % BLOCK_SIZE) + bh->b_data;
-		copy_from_user(p,buf,c);
-		update_vm_cache(inode, pos, p, 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;
-}