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5dfe4c964a
Many struct file_operations in the kernel can be "const". Marking them const moves these to the .rodata section, which avoids false sharing with potential dirty data. In addition it'll catch accidental writes at compile time to these shared resources. [akpm@osdl.org: sparc64 fix] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
124 lines
3.1 KiB
C
124 lines
3.1 KiB
C
/*
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* Copyright (C) 2001 Mike Corrigan & Dave Engebretsen IBM Corporation
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <linux/init.h>
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#include <linux/mm.h>
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#include <linux/proc_fs.h>
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#include <linux/slab.h>
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#include <linux/kernel.h>
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#include <asm/machdep.h>
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#include <asm/vdso_datapage.h>
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#include <asm/rtas.h>
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#include <asm/uaccess.h>
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#include <asm/prom.h>
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static loff_t page_map_seek( struct file *file, loff_t off, int whence);
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static ssize_t page_map_read( struct file *file, char __user *buf, size_t nbytes,
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loff_t *ppos);
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static int page_map_mmap( struct file *file, struct vm_area_struct *vma );
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static const struct file_operations page_map_fops = {
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.llseek = page_map_seek,
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.read = page_map_read,
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.mmap = page_map_mmap
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};
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/*
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* Create the ppc64 and ppc64/rtas directories early. This allows us to
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* assume that they have been previously created in drivers.
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*/
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static int __init proc_ppc64_create(void)
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{
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struct proc_dir_entry *root;
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root = proc_mkdir("ppc64", NULL);
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if (!root)
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return 1;
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if (!of_find_node_by_path("/rtas"))
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return 0;
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if (!proc_mkdir("rtas", root))
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return 1;
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if (!proc_symlink("rtas", NULL, "ppc64/rtas"))
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return 1;
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return 0;
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}
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core_initcall(proc_ppc64_create);
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static int __init proc_ppc64_init(void)
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{
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struct proc_dir_entry *pde;
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pde = create_proc_entry("ppc64/systemcfg", S_IFREG|S_IRUGO, NULL);
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if (!pde)
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return 1;
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pde->data = vdso_data;
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pde->size = PAGE_SIZE;
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pde->proc_fops = &page_map_fops;
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return 0;
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}
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__initcall(proc_ppc64_init);
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static loff_t page_map_seek( struct file *file, loff_t off, int whence)
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{
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loff_t new;
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struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
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switch(whence) {
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case 0:
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new = off;
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break;
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case 1:
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new = file->f_pos + off;
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break;
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case 2:
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new = dp->size + off;
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break;
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default:
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return -EINVAL;
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}
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if ( new < 0 || new > dp->size )
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return -EINVAL;
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return (file->f_pos = new);
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}
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static ssize_t page_map_read( struct file *file, char __user *buf, size_t nbytes,
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loff_t *ppos)
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{
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struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
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return simple_read_from_buffer(buf, nbytes, ppos, dp->data, dp->size);
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}
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static int page_map_mmap( struct file *file, struct vm_area_struct *vma )
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{
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struct proc_dir_entry *dp = PDE(file->f_path.dentry->d_inode);
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if ((vma->vm_end - vma->vm_start) > dp->size)
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return -EINVAL;
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remap_pfn_range(vma, vma->vm_start, __pa(dp->data) >> PAGE_SHIFT,
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dp->size, vma->vm_page_prot);
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return 0;
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}
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