linux_dsm_epyc7002/fs/ncpfs/mmap.c
Dave Jiang 11bac80004 mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf
->fault(), ->page_mkwrite(), and ->pfn_mkwrite() calls do not need to
take a vma and vmf parameter when the vma already resides in vmf.

Remove the vma parameter to simplify things.

[arnd@arndb.de: fix ARM build]
  Link: http://lkml.kernel.org/r/20170125223558.1451224-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/148521301778.19116.10840599906674778980.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:54 -08:00

125 lines
2.8 KiB
C

/*
* mmap.c
*
* Copyright (C) 1995, 1996 by Volker Lendecke
* Modified 1997 Peter Waltenberg, Bill Hawes, David Woodhouse for 2.1 dcache
*
*/
#include <linux/stat.h>
#include <linux/time.h>
#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/mm.h>
#include <linux/shm.h>
#include <linux/errno.h>
#include <linux/mman.h>
#include <linux/string.h>
#include <linux/fcntl.h>
#include <linux/memcontrol.h>
#include <linux/uaccess.h>
#include "ncp_fs.h"
/*
* Fill in the supplied page for mmap
* XXX: how are we excluding truncate/invalidate here? Maybe need to lock
* page?
*/
static int ncp_file_mmap_fault(struct vm_fault *vmf)
{
struct inode *inode = file_inode(vmf->vma->vm_file);
char *pg_addr;
unsigned int already_read;
unsigned int count;
int bufsize;
int pos; /* XXX: loff_t ? */
/*
* ncpfs has nothing against high pages as long
* as recvmsg and memset works on it
*/
vmf->page = alloc_page(GFP_HIGHUSER);
if (!vmf->page)
return VM_FAULT_OOM;
pg_addr = kmap(vmf->page);
pos = vmf->pgoff << PAGE_SHIFT;
count = PAGE_SIZE;
/* what we can read in one go */
bufsize = NCP_SERVER(inode)->buffer_size;
already_read = 0;
if (ncp_make_open(inode, O_RDONLY) >= 0) {
while (already_read < count) {
int read_this_time;
int to_read;
to_read = bufsize - (pos % bufsize);
to_read = min_t(unsigned int, to_read, count - already_read);
if (ncp_read_kernel(NCP_SERVER(inode),
NCP_FINFO(inode)->file_handle,
pos, to_read,
pg_addr + already_read,
&read_this_time) != 0) {
read_this_time = 0;
}
pos += read_this_time;
already_read += read_this_time;
if (read_this_time < to_read) {
break;
}
}
ncp_inode_close(inode);
}
if (already_read < PAGE_SIZE)
memset(pg_addr + already_read, 0, PAGE_SIZE - already_read);
flush_dcache_page(vmf->page);
kunmap(vmf->page);
/*
* If I understand ncp_read_kernel() properly, the above always
* fetches from the network, here the analogue of disk.
* -- nyc
*/
count_vm_event(PGMAJFAULT);
mem_cgroup_count_vm_event(vmf->vma->vm_mm, PGMAJFAULT);
return VM_FAULT_MAJOR;
}
static const struct vm_operations_struct ncp_file_mmap =
{
.fault = ncp_file_mmap_fault,
};
/* This is used for a general mmap of a ncp file */
int ncp_mmap(struct file *file, struct vm_area_struct *vma)
{
struct inode *inode = file_inode(file);
ncp_dbg(1, "called\n");
if (!ncp_conn_valid(NCP_SERVER(inode)))
return -EIO;
/* only PAGE_COW or read-only supported now */
if (vma->vm_flags & VM_SHARED)
return -EINVAL;
/* we do not support files bigger than 4GB... We eventually
supports just 4GB... */
if (vma_pages(vma) + vma->vm_pgoff
> (1U << (32 - PAGE_SHIFT)))
return -EFBIG;
vma->vm_ops = &ncp_file_mmap;
file_accessed(file);
return 0;
}