linux/fs/exofs/namei.c
Kirill A. Shutemov 09cbfeaf1a mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04 10:41:08 -07:00

320 lines
7.2 KiB
C

/*
* Copyright (C) 2005, 2006
* Avishay Traeger (avishay@gmail.com)
* Copyright (C) 2008, 2009
* Boaz Harrosh <ooo@electrozaur.com>
*
* Copyrights for code taken from ext2:
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
* from
* linux/fs/minix/inode.c
* Copyright (C) 1991, 1992 Linus Torvalds
*
* This file is part of exofs.
*
* exofs is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation. Since it is based on ext2, and the only
* valid version of GPL for the Linux kernel is version 2, the only valid
* version of GPL for exofs is version 2.
*
* exofs is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with exofs; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "exofs.h"
static inline int exofs_add_nondir(struct dentry *dentry, struct inode *inode)
{
int err = exofs_add_link(dentry, inode);
if (!err) {
d_instantiate(dentry, inode);
return 0;
}
inode_dec_link_count(inode);
iput(inode);
return err;
}
static struct dentry *exofs_lookup(struct inode *dir, struct dentry *dentry,
unsigned int flags)
{
struct inode *inode;
ino_t ino;
if (dentry->d_name.len > EXOFS_NAME_LEN)
return ERR_PTR(-ENAMETOOLONG);
ino = exofs_inode_by_name(dir, dentry);
inode = ino ? exofs_iget(dir->i_sb, ino) : NULL;
return d_splice_alias(inode, dentry);
}
static int exofs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
bool excl)
{
struct inode *inode = exofs_new_inode(dir, mode);
int err = PTR_ERR(inode);
if (!IS_ERR(inode)) {
inode->i_op = &exofs_file_inode_operations;
inode->i_fop = &exofs_file_operations;
inode->i_mapping->a_ops = &exofs_aops;
mark_inode_dirty(inode);
err = exofs_add_nondir(dentry, inode);
}
return err;
}
static int exofs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
dev_t rdev)
{
struct inode *inode;
int err;
inode = exofs_new_inode(dir, mode);
err = PTR_ERR(inode);
if (!IS_ERR(inode)) {
init_special_inode(inode, inode->i_mode, rdev);
mark_inode_dirty(inode);
err = exofs_add_nondir(dentry, inode);
}
return err;
}
static int exofs_symlink(struct inode *dir, struct dentry *dentry,
const char *symname)
{
struct super_block *sb = dir->i_sb;
int err = -ENAMETOOLONG;
unsigned l = strlen(symname)+1;
struct inode *inode;
struct exofs_i_info *oi;
if (l > sb->s_blocksize)
goto out;
inode = exofs_new_inode(dir, S_IFLNK | S_IRWXUGO);
err = PTR_ERR(inode);
if (IS_ERR(inode))
goto out;
oi = exofs_i(inode);
if (l > sizeof(oi->i_data)) {
/* slow symlink */
inode->i_op = &page_symlink_inode_operations;
inode_nohighmem(inode);
inode->i_mapping->a_ops = &exofs_aops;
memset(oi->i_data, 0, sizeof(oi->i_data));
err = page_symlink(inode, symname, l);
if (err)
goto out_fail;
} else {
/* fast symlink */
inode->i_op = &simple_symlink_inode_operations;
inode->i_link = (char *)oi->i_data;
memcpy(oi->i_data, symname, l);
inode->i_size = l-1;
}
mark_inode_dirty(inode);
err = exofs_add_nondir(dentry, inode);
out:
return err;
out_fail:
inode_dec_link_count(inode);
iput(inode);
goto out;
}
static int exofs_link(struct dentry *old_dentry, struct inode *dir,
struct dentry *dentry)
{
struct inode *inode = d_inode(old_dentry);
inode->i_ctime = CURRENT_TIME;
inode_inc_link_count(inode);
ihold(inode);
return exofs_add_nondir(dentry, inode);
}
static int exofs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
struct inode *inode;
int err;
inode_inc_link_count(dir);
inode = exofs_new_inode(dir, S_IFDIR | mode);
err = PTR_ERR(inode);
if (IS_ERR(inode))
goto out_dir;
inode->i_op = &exofs_dir_inode_operations;
inode->i_fop = &exofs_dir_operations;
inode->i_mapping->a_ops = &exofs_aops;
inode_inc_link_count(inode);
err = exofs_make_empty(inode, dir);
if (err)
goto out_fail;
err = exofs_add_link(dentry, inode);
if (err)
goto out_fail;
d_instantiate(dentry, inode);
out:
return err;
out_fail:
inode_dec_link_count(inode);
inode_dec_link_count(inode);
iput(inode);
out_dir:
inode_dec_link_count(dir);
goto out;
}
static int exofs_unlink(struct inode *dir, struct dentry *dentry)
{
struct inode *inode = d_inode(dentry);
struct exofs_dir_entry *de;
struct page *page;
int err = -ENOENT;
de = exofs_find_entry(dir, dentry, &page);
if (!de)
goto out;
err = exofs_delete_entry(de, page);
if (err)
goto out;
inode->i_ctime = dir->i_ctime;
inode_dec_link_count(inode);
err = 0;
out:
return err;
}
static int exofs_rmdir(struct inode *dir, struct dentry *dentry)
{
struct inode *inode = d_inode(dentry);
int err = -ENOTEMPTY;
if (exofs_empty_dir(inode)) {
err = exofs_unlink(dir, dentry);
if (!err) {
inode->i_size = 0;
inode_dec_link_count(inode);
inode_dec_link_count(dir);
}
}
return err;
}
static int exofs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode *new_dir, struct dentry *new_dentry)
{
struct inode *old_inode = d_inode(old_dentry);
struct inode *new_inode = d_inode(new_dentry);
struct page *dir_page = NULL;
struct exofs_dir_entry *dir_de = NULL;
struct page *old_page;
struct exofs_dir_entry *old_de;
int err = -ENOENT;
old_de = exofs_find_entry(old_dir, old_dentry, &old_page);
if (!old_de)
goto out;
if (S_ISDIR(old_inode->i_mode)) {
err = -EIO;
dir_de = exofs_dotdot(old_inode, &dir_page);
if (!dir_de)
goto out_old;
}
if (new_inode) {
struct page *new_page;
struct exofs_dir_entry *new_de;
err = -ENOTEMPTY;
if (dir_de && !exofs_empty_dir(new_inode))
goto out_dir;
err = -ENOENT;
new_de = exofs_find_entry(new_dir, new_dentry, &new_page);
if (!new_de)
goto out_dir;
err = exofs_set_link(new_dir, new_de, new_page, old_inode);
new_inode->i_ctime = CURRENT_TIME;
if (dir_de)
drop_nlink(new_inode);
inode_dec_link_count(new_inode);
if (err)
goto out_dir;
} else {
err = exofs_add_link(new_dentry, old_inode);
if (err)
goto out_dir;
if (dir_de)
inode_inc_link_count(new_dir);
}
old_inode->i_ctime = CURRENT_TIME;
exofs_delete_entry(old_de, old_page);
mark_inode_dirty(old_inode);
if (dir_de) {
err = exofs_set_link(old_inode, dir_de, dir_page, new_dir);
inode_dec_link_count(old_dir);
if (err)
goto out_dir;
}
return 0;
out_dir:
if (dir_de) {
kunmap(dir_page);
put_page(dir_page);
}
out_old:
kunmap(old_page);
put_page(old_page);
out:
return err;
}
const struct inode_operations exofs_dir_inode_operations = {
.create = exofs_create,
.lookup = exofs_lookup,
.link = exofs_link,
.unlink = exofs_unlink,
.symlink = exofs_symlink,
.mkdir = exofs_mkdir,
.rmdir = exofs_rmdir,
.mknod = exofs_mknod,
.rename = exofs_rename,
.setattr = exofs_setattr,
};
const struct inode_operations exofs_special_inode_operations = {
.setattr = exofs_setattr,
};