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![Nadia Yvette Chambers](/assets/img/avatar_default.png)
I've legally changed my name with New York State, the US Social Security Administration, et al. This patch propagates the name change and change in initials and login to comments in the kernel source as well. Signed-off-by: Nadia Yvette Chambers <nyc@holomorphy.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
127 lines
2.9 KiB
C
127 lines
2.9 KiB
C
/*
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* mmap.c
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*
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* Copyright (C) 1995, 1996 by Volker Lendecke
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* Modified 1997 Peter Waltenberg, Bill Hawes, David Woodhouse for 2.1 dcache
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*
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*/
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#include <linux/stat.h>
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#include <linux/time.h>
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#include <linux/kernel.h>
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#include <linux/gfp.h>
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#include <linux/mm.h>
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#include <linux/shm.h>
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#include <linux/errno.h>
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#include <linux/mman.h>
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#include <linux/string.h>
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#include <linux/fcntl.h>
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#include <linux/memcontrol.h>
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#include <asm/uaccess.h>
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#include "ncp_fs.h"
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/*
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* Fill in the supplied page for mmap
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* XXX: how are we excluding truncate/invalidate here? Maybe need to lock
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* page?
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*/
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static int ncp_file_mmap_fault(struct vm_area_struct *area,
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struct vm_fault *vmf)
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{
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struct file *file = area->vm_file;
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struct dentry *dentry = file->f_path.dentry;
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struct inode *inode = dentry->d_inode;
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char *pg_addr;
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unsigned int already_read;
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unsigned int count;
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int bufsize;
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int pos; /* XXX: loff_t ? */
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/*
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* ncpfs has nothing against high pages as long
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* as recvmsg and memset works on it
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*/
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vmf->page = alloc_page(GFP_HIGHUSER);
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if (!vmf->page)
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return VM_FAULT_OOM;
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pg_addr = kmap(vmf->page);
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pos = vmf->pgoff << PAGE_SHIFT;
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count = PAGE_SIZE;
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/* what we can read in one go */
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bufsize = NCP_SERVER(inode)->buffer_size;
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already_read = 0;
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if (ncp_make_open(inode, O_RDONLY) >= 0) {
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while (already_read < count) {
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int read_this_time;
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int to_read;
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to_read = bufsize - (pos % bufsize);
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to_read = min_t(unsigned int, to_read, count - already_read);
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if (ncp_read_kernel(NCP_SERVER(inode),
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NCP_FINFO(inode)->file_handle,
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pos, to_read,
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pg_addr + already_read,
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&read_this_time) != 0) {
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read_this_time = 0;
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}
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pos += read_this_time;
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already_read += read_this_time;
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if (read_this_time < to_read) {
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break;
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}
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}
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ncp_inode_close(inode);
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}
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if (already_read < PAGE_SIZE)
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memset(pg_addr + already_read, 0, PAGE_SIZE - already_read);
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flush_dcache_page(vmf->page);
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kunmap(vmf->page);
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/*
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* If I understand ncp_read_kernel() properly, the above always
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* fetches from the network, here the analogue of disk.
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* -- nyc
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*/
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count_vm_event(PGMAJFAULT);
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mem_cgroup_count_vm_event(area->vm_mm, PGMAJFAULT);
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return VM_FAULT_MAJOR;
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}
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static const struct vm_operations_struct ncp_file_mmap =
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{
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.fault = ncp_file_mmap_fault,
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};
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/* This is used for a general mmap of a ncp file */
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int ncp_mmap(struct file *file, struct vm_area_struct *vma)
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{
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struct inode *inode = file->f_path.dentry->d_inode;
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DPRINTK("ncp_mmap: called\n");
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if (!ncp_conn_valid(NCP_SERVER(inode)))
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return -EIO;
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/* only PAGE_COW or read-only supported now */
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if (vma->vm_flags & VM_SHARED)
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return -EINVAL;
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/* we do not support files bigger than 4GB... We eventually
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supports just 4GB... */
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if (((vma->vm_end - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff
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> (1U << (32 - PAGE_SHIFT)))
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return -EFBIG;
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vma->vm_ops = &ncp_file_mmap;
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file_accessed(file);
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return 0;
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}
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