patch-1.3.60 linux/fs/msdos/mmap.c
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- Lines: 114
- Date:
Thu Jan 1 02:00:00 1970
- Orig file:
v1.3.59/linux/fs/msdos/mmap.c
- Orig date:
Mon Jan 8 14:10:27 1996
diff -u --recursive --new-file v1.3.59/linux/fs/msdos/mmap.c linux/fs/msdos/mmap.c
@@ -1,113 +0,0 @@
-/*
- * fs/msdos/mmap.c
- *
- * Written by Jacques Gelinas (jacques@solucorp.qc.ca)
- * Inspired by fs/nfs/mmap.c (Jon Tombs 15 Aug 1993)
- *
- * msdos mmap handling
- */
-
-#include <linux/stat.h>
-#include <linux/sched.h>
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/shm.h>
-#include <linux/errno.h>
-#include <linux/mman.h>
-#include <linux/string.h>
-#include <linux/malloc.h>
-#include <linux/msdos_fs.h>
-
-#include <asm/segment.h>
-#include <asm/system.h>
-
-/*
- * Fill in the supplied page for mmap
- */
-static unsigned long msdos_file_mmap_nopage(
- struct vm_area_struct * area,
- unsigned long address,
- int error_code)
-{
- struct inode * inode = area->vm_inode;
- unsigned long page;
- unsigned int clear;
- int 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;
- if (gap < PAGE_SIZE){
- clear = PAGE_SIZE - gap;
- }
- filp.f_reada = 0;
- filp.f_pos = pos;
- need_read = PAGE_SIZE - clear;
- {
- unsigned long cur_fs = get_fs();
- set_fs (KERNEL_DS);
- cur_read = msdos_file_read (inode,&filp,(char*)page
- ,need_read);
- set_fs (cur_fs);
- }
- if (cur_read != need_read){
- printk ("MSDOS: Error while reading an mmap file %d <> %d\n"
- ,cur_read,need_read);
- }
- }
- if (clear > 0){
- memset ((char*)page+PAGE_SIZE-clear,0,clear);
- }
- return page;
-}
-
-struct vm_operations_struct msdos_file_mmap = {
- NULL, /* open */
- NULL, /* close */
- NULL, /* unmap */
- NULL, /* protect */
- NULL, /* sync */
- NULL, /* advise */
- msdos_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 msdos_mmap(struct inode * inode, struct file * file, struct vm_area_struct * vma)
-{
- 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;
- inode->i_dirt = 1;
- }
-
- vma->vm_inode = inode;
- inode->i_count++;
- vma->vm_ops = &msdos_file_mmap;
- return 0;
-}
-
-
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with Sam's (original) version of this