patch-2.3.9 linux/fs/hpfs/mmap.c

• Lines: 129
• Date: Wed Dec 31 16:00:00 1969
• Orig file: v2.3.8/linux/fs/hpfs/mmap.c
• Orig date: Thu May 13 23:48:20 1999

diff -u --recursive --new-file v2.3.8/linux/fs/hpfs/mmap.c linux/fs/hpfs/mmap.c
@@ -1,128 +0,0 @@
-/*
- *  linux/fs/hpfs/mmap.c
- *
- *  taken from fat filesystem
- *
- *  Written by Jacques Gelinas (jacques@solucorp.qc.ca)
- *  Inspired by fs/nfs/mmap.c (Jon Tombs 15 Aug 1993)
- *
- *  Modified for HPFS by Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz)
- *
- *  mmap handling for hpfs filesystem
- *	(generic_file_mmap may be used only on filesystems that keep zeros
- *	 in last file sector beyond end)
- */
-
-/*
- * generic_file_mmap doesn't erase the space beyond file end in last sector. :-(
- * Hpfs doesn't keep zeros in last sector. This causes problems with kernel
- * mkdep.c and probably other programs. Additionally this could be a security
- * hole - some interesting data, like pieces of /etc/shadow could be found
- * beyond file end.
- *
- * So, I can't use generic mmap. mmap from fat filesystem looks good, so I used
- * it.
- *
- * BTW. fat uses generic mmap on normal disks. Doesn't it also have above bugs?
- * I don't think Msdos erases space in last sector.
- *
- * If you fix generic_file_mmap, you can remove this file and use it.
- */
-
-#include "hpfs_fn.h"
-
-/*
- * Fill in the supplied page for mmap
- */
-
-static unsigned long hpfs_file_mmap_nopage(
-	struct vm_area_struct * area,
-	unsigned long address,
-	int error_code)
-{
-	/*struct inode * inode = area->vm_inode;*/
-	struct inode * inode = area->vm_file->f_dentry->d_inode;
-	unsigned long page;
-	unsigned int clear;
-	loff_t pos;
-	long gap;	/* distance from eof to pos */
-
-	page = __get_free_page(GFP_KERNEL);
-	if (!page)
-		return page;
-	address &= PAGE_MASK;
-	pos = address - area->vm_start + area->vm_offset;
-
-	clear = 0;
-	gap = inode->i_size - pos;
-	if (gap <= 0){
-		/* mmaping beyond end of file */
-		clear = PAGE_SIZE;
-	}else{
-		int cur_read;
-		int need_read;
-		/*struct file *filp = area->vm_file;*/
-		struct file filp;
-		if (gap < PAGE_SIZE){
-			clear = PAGE_SIZE - gap;
-		}
-		filp.f_reada = 0;
-		filp.f_pos = pos;
-		filp.f_dentry=area->vm_file->f_dentry;
-		need_read = PAGE_SIZE - clear;
-		{
-			mm_segment_t cur_fs = get_fs();
-			set_fs (KERNEL_DS);
-			cur_read = generic_file_read (&filp,(char*)page
-				,need_read,&pos);
-			set_fs (cur_fs);
-		}
-		if (cur_read != need_read){
-			hpfs_error(inode->i_sb, "Error while reading an mmap file %08x", inode->i_ino);
-		}
-	}
-	if (clear > 0){
-		memset ((char*)page+PAGE_SIZE-clear,0,clear);
-	}
-	return page;
-}
-
-struct vm_operations_struct hpfs_file_mmap = {
-	NULL,			/* open */
-	NULL,			/* close */
-	NULL,			/* unmap */
-	NULL,			/* protect */
-	NULL,			/* sync */
-	NULL,			/* advise */
-	hpfs_file_mmap_nopage,	/* nopage */
-	NULL,			/* wppage */
-	NULL,			/* swapout */
-	NULL,			/* swapin */
-};
-
-/*
- * This is used for a general mmap of an msdos file
- * Returns 0 if ok, or a negative error code if not.
- */
-int hpfs_mmap(struct file * file, struct vm_area_struct * vma)
-{
-	struct inode *inode = file->f_dentry->d_inode;
-	/*printk("start mmap\n");*/
-	if (vma->vm_flags & VM_SHARED)	/* only PAGE_COW or read-only supported now */
-		return -EINVAL;
-	if (vma->vm_offset & (inode->i_sb->s_blocksize - 1))
-		return -EINVAL;
-	if (!inode->i_sb || !S_ISREG(inode->i_mode))
-		return -EACCES;
-	/*if (!IS_RDONLY(inode)) {
-		inode->i_atime = CURRENT_TIME;
-		mark_inode_dirty(inode);
-	}*/
-
-	vma->vm_file = file;
-	/*inode->i_count++;*/
-	file->f_count++;
-	vma->vm_ops = &hpfs_file_mmap;
-	/*printk("end mmap\n");*/
-	return 0;
-}