patch-2.1.112 linux/fs/ufs/file.c

• Lines: 282
• Date: Sun Jul 26 01:20:22 1998
• Orig file: v2.1.111/linux/fs/ufs/file.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.111/linux/fs/ufs/file.c linux/fs/ufs/file.c
@@ -0,0 +1,281 @@
+/*
+ *  linux/fs/ufs/file.c
+ *
+ * Copyright (C) 1998
+ * Daniel Pirkl <daniel.pirkl@email.cz>
+ * Charles University, Faculty of Mathematics and Physics
+ *
+ *  from
+ *
+ *  linux/fs/ext2/file.c
+ *
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ *
+ *  from
+ *
+ *  linux/fs/minix/file.c
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ *
+ *  ext2 fs regular file handling primitives
+ */
+
+#include <asm/uaccess.h>
+#include <asm/system.h>
+
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/ufs_fs.h>
+#include <linux/fcntl.h>
+#include <linux/sched.h>
+#include <linux/stat.h>
+#include <linux/locks.h>
+#include <linux/mm.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/ufs_fs.h>
+
+static long long ufs_file_lseek(struct file *, long long, int);
+static ssize_t ufs_file_write (struct file *, const char *, size_t, loff_t *);
+static int ufs_release_file (struct inode *, struct file *);
+
+/*
+ * We have mostly NULL's here: the current defaults are ok for
+ * the ufs filesystem.
+ */
+static struct file_operations ufs_file_operations = {
+	ufs_file_lseek,	/* lseek */
+	generic_file_read,	/* read */
+	ufs_file_write, 	/* write */
+	NULL,			/* readdir - bad */
+	NULL,			/* poll - default */
+	NULL, 			/* ioctl */
+	generic_file_mmap,	/* mmap */
+	NULL,			/* no special open is needed */
+	ufs_release_file,	/* release */
+	NULL, 			/* fsync */
+	NULL,			/* fasync */
+	NULL,			/* check_media_change */
+	NULL			/* revalidate */
+};
+
+struct inode_operations ufs_file_inode_operations = {
+	&ufs_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 */
+	ufs_bmap,		/* bmap */
+	ufs_truncate,		/* truncate */
+	NULL, 			/* permission */
+	NULL			/* smap */
+};
+
+/*
+ * Make sure the offset never goes beyond the 32-bit mark..
+ */
+static long long ufs_file_lseek(
+	struct file *file,
+	long long offset,
+	int origin )
+{
+	long long retval;
+	struct inode *inode = file->f_dentry->d_inode;
+
+	switch (origin) {
+		case 2:
+			offset += inode->i_size;
+			break;
+		case 1:
+			offset += file->f_pos;
+	}
+	retval = -EINVAL;
+	/* make sure the offset fits in 32 bits */
+	if (((unsigned long long) offset >> 32) == 0) {
+		if (offset != file->f_pos) {
+			file->f_pos = offset;
+			file->f_reada = 0;
+			file->f_version = ++event;
+		}
+		retval = offset;
+	}
+	return retval;
+}
+
+static inline void remove_suid(struct inode *inode)
+{
+	unsigned int mode;
+
+	/* set S_IGID if S_IXGRP is set, and always set S_ISUID */
+	mode = (inode->i_mode & S_IXGRP)*(S_ISGID/S_IXGRP) | S_ISUID;
+
+	/* was any of the uid bits set? */
+	mode &= inode->i_mode;
+	if (mode && !suser()) {
+		inode->i_mode &= ~mode;
+		mark_inode_dirty(inode);
+	}
+}
+
+static ssize_t ufs_file_write (
+	struct file * filp,
+	const char * buf,
+	size_t count,
+	loff_t *ppos )
+{
+	struct inode * inode = filp->f_dentry->d_inode;
+	__u32 pos;
+	long block;
+	int offset;
+	int written, c;
+	struct buffer_head * bh, *bufferlist[NBUF];
+	struct super_block * sb;
+	int err;
+	int i,buffercount,write_error;
+
+	/* POSIX: mtime/ctime may not change for 0 count */
+	if (!count)
+		return 0;
+	write_error = buffercount = 0;
+	if (!inode)
+		return -EINVAL;
+	sb = inode->i_sb;
+	if (sb->s_flags & MS_RDONLY)
+		/*
+		 * This fs has been automatically remounted ro because of errors
+		 */
+		return -ENOSPC;
+
+	if (!S_ISREG(inode->i_mode)) {
+		ufs_warning (sb, "ufs_file_write", "mode = %07o",
+			      inode->i_mode);
+		return -EINVAL;
+	}
+	remove_suid(inode);
+
+	if (filp->f_flags & O_APPEND)
+		pos = inode->i_size;
+	else {
+		pos = *ppos;
+		if (pos != *ppos)
+			return -EINVAL;
+	}
+
+	/* Check for overflow.. */
+	if (pos > (__u32) (pos + count)) {
+		count = ~pos; /* == 0xFFFFFFFF - pos */
+		if (!count)
+			return -EFBIG;
+	}
+
+	/*
+	 * If a file has been opened in synchronous mode, we have to ensure
+	 * that meta-data will also be written synchronously.  Thus, we
+	 * set the i_osync field.  This field is tested by the allocation
+	 * routines.
+	 */
+	if (filp->f_flags & O_SYNC)
+		inode->u.ufs_i.i_osync++;
+	block = pos >> sb->s_blocksize_bits;
+	offset = pos & (sb->s_blocksize - 1);
+	c = sb->s_blocksize - offset;
+	written = 0;
+	do {
+		bh = ufs_getfrag (inode, block, 1, &err);
+		if (!bh) {
+			if (!written)
+				written = err;
+			break;
+		}
+		if (c > count)
+			c = count;
+		if (c != sb->s_blocksize && !buffer_uptodate(bh)) {
+			ll_rw_block (READ, 1, &bh);
+			wait_on_buffer (bh);
+			if (!buffer_uptodate(bh)) {
+				brelse (bh);
+				if (!written)
+					written = -EIO;
+				break;
+			}
+		}
+		c -= copy_from_user (bh->b_data + offset, buf, c);
+		if (!c) {
+			brelse(bh);
+			if (!written)
+				written = -EFAULT;
+			break;
+		}
+		update_vm_cache(inode, pos, bh->b_data + offset, c);
+		pos += c;
+		written += c;
+		buf += c;
+		count -= c;
+		mark_buffer_uptodate(bh, 1);
+		mark_buffer_dirty(bh, 0);
+		if (filp->f_flags & O_SYNC)
+			bufferlist[buffercount++] = bh;
+		else
+			brelse(bh);
+		if (buffercount == NBUF){
+			ll_rw_block(WRITE, buffercount, bufferlist);
+			for(i=0; i<buffercount; i++){
+				wait_on_buffer(bufferlist[i]);
+				if (!buffer_uptodate(bufferlist[i]))
+					write_error=1;
+				brelse(bufferlist[i]);
+			}
+			buffercount=0;
+		}
+		if (write_error)
+			break;
+		block++;
+		offset = 0;
+		c = sb->s_blocksize;
+	} while (count);
+	if (buffercount){
+		ll_rw_block(WRITE, buffercount, bufferlist);
+		for (i=0; i<buffercount; i++){
+			wait_on_buffer(bufferlist[i]);
+			if (!buffer_uptodate(bufferlist[i]))
+				write_error=1;
+			brelse(bufferlist[i]);
+		}
+	}		
+	if (pos > inode->i_size)
+		inode->i_size = pos;
+	if (filp->f_flags & O_SYNC)
+		inode->u.ufs_i.i_osync--;
+	inode->i_ctime = inode->i_mtime = CURRENT_TIME;
+	*ppos = pos;
+	mark_inode_dirty(inode);
+	return written;
+}
+
+/*
+ * Called when an inode is released. Note that this is different
+ * from ufs_open: open gets called at every open, but release
+ * gets called only when /all/ the files are closed.
+ */
+static int ufs_release_file (struct inode * inode, struct file * filp)
+{
+	return 0;
+}