/usr/src/aufs-4.9+20161219/fs/aufs/file.c is in aufs-dkms 4.9+20161219-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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* Copyright (C) 2005-2016 Junjiro R. Okajima
*
* This program, aufs 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; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* handling file/dir, and address_space operation
*/
#ifdef CONFIG_AUFS_DEBUG
#include <linux/migrate.h>
#endif
#include <linux/pagemap.h>
#include "aufs.h"
/* drop flags for writing */
unsigned int au_file_roflags(unsigned int flags)
{
flags &= ~(O_WRONLY | O_RDWR | O_APPEND | O_CREAT | O_TRUNC);
flags |= O_RDONLY | O_NOATIME;
return flags;
}
/* common functions to regular file and dir */
struct file *au_h_open(struct dentry *dentry, aufs_bindex_t bindex, int flags,
struct file *file, int force_wr)
{
struct file *h_file;
struct dentry *h_dentry;
struct inode *h_inode;
struct super_block *sb;
struct au_branch *br;
struct path h_path;
int err;
/* a race condition can happen between open and unlink/rmdir */
h_file = ERR_PTR(-ENOENT);
h_dentry = au_h_dptr(dentry, bindex);
if (au_test_nfsd() && (!h_dentry || d_is_negative(h_dentry)))
goto out;
h_inode = d_inode(h_dentry);
spin_lock(&h_dentry->d_lock);
err = (!d_unhashed(dentry) && d_unlinked(h_dentry))
/* || !d_inode(dentry)->i_nlink */
;
spin_unlock(&h_dentry->d_lock);
if (unlikely(err))
goto out;
sb = dentry->d_sb;
br = au_sbr(sb, bindex);
err = au_br_test_oflag(flags, br);
h_file = ERR_PTR(err);
if (unlikely(err))
goto out;
/* drop flags for writing */
if (au_test_ro(sb, bindex, d_inode(dentry))) {
if (force_wr && !(flags & O_WRONLY))
force_wr = 0;
flags = au_file_roflags(flags);
if (force_wr) {
h_file = ERR_PTR(-EROFS);
flags = au_file_roflags(flags);
if (unlikely(vfsub_native_ro(h_inode)
|| IS_APPEND(h_inode)))
goto out;
flags &= ~O_ACCMODE;
flags |= O_WRONLY;
}
}
flags &= ~O_CREAT;
au_br_get(br);
h_path.dentry = h_dentry;
h_path.mnt = au_br_mnt(br);
h_file = vfsub_dentry_open(&h_path, flags);
if (IS_ERR(h_file))
goto out_br;
if (flags & __FMODE_EXEC) {
err = deny_write_access(h_file);
if (unlikely(err)) {
fput(h_file);
h_file = ERR_PTR(err);
goto out_br;
}
}
fsnotify_open(h_file);
goto out; /* success */
out_br:
au_br_put(br);
out:
return h_file;
}
static int au_cmoo(struct dentry *dentry)
{
int err, cmoo;
unsigned int udba;
struct path h_path;
struct au_pin pin;
struct au_cp_generic cpg = {
.dentry = dentry,
.bdst = -1,
.bsrc = -1,
.len = -1,
.pin = &pin,
.flags = AuCpup_DTIME | AuCpup_HOPEN
};
struct inode *delegated;
struct super_block *sb;
struct au_sbinfo *sbinfo;
struct au_fhsm *fhsm;
pid_t pid;
struct au_branch *br;
struct dentry *parent;
struct au_hinode *hdir;
DiMustWriteLock(dentry);
IiMustWriteLock(d_inode(dentry));
err = 0;
if (IS_ROOT(dentry))
goto out;
cpg.bsrc = au_dbtop(dentry);
if (!cpg.bsrc)
goto out;
sb = dentry->d_sb;
sbinfo = au_sbi(sb);
fhsm = &sbinfo->si_fhsm;
pid = au_fhsm_pid(fhsm);
if (pid
&& (current->pid == pid
|| current->real_parent->pid == pid))
goto out;
br = au_sbr(sb, cpg.bsrc);
cmoo = au_br_cmoo(br->br_perm);
if (!cmoo)
goto out;
if (!d_is_reg(dentry))
cmoo &= AuBrAttr_COO_ALL;
if (!cmoo)
goto out;
parent = dget_parent(dentry);
di_write_lock_parent(parent);
err = au_wbr_do_copyup_bu(dentry, cpg.bsrc - 1);
cpg.bdst = err;
if (unlikely(err < 0)) {
err = 0; /* there is no upper writable branch */
goto out_dgrade;
}
AuDbg("bsrc %d, bdst %d\n", cpg.bsrc, cpg.bdst);
/* do not respect the coo attrib for the target branch */
err = au_cpup_dirs(dentry, cpg.bdst);
if (unlikely(err))
goto out_dgrade;
di_downgrade_lock(parent, AuLock_IR);
udba = au_opt_udba(sb);
err = au_pin(&pin, dentry, cpg.bdst, udba,
AuPin_DI_LOCKED | AuPin_MNT_WRITE);
if (unlikely(err))
goto out_parent;
err = au_sio_cpup_simple(&cpg);
au_unpin(&pin);
if (unlikely(err))
goto out_parent;
if (!(cmoo & AuBrWAttr_MOO))
goto out_parent; /* success */
err = au_pin(&pin, dentry, cpg.bsrc, udba,
AuPin_DI_LOCKED | AuPin_MNT_WRITE);
if (unlikely(err))
goto out_parent;
h_path.mnt = au_br_mnt(br);
h_path.dentry = au_h_dptr(dentry, cpg.bsrc);
hdir = au_hi(d_inode(parent), cpg.bsrc);
delegated = NULL;
err = vfsub_unlink(hdir->hi_inode, &h_path, &delegated, /*force*/1);
au_unpin(&pin);
/* todo: keep h_dentry or not? */
if (unlikely(err == -EWOULDBLOCK)) {
pr_warn("cannot retry for NFSv4 delegation"
" for an internal unlink\n");
iput(delegated);
}
if (unlikely(err)) {
pr_err("unlink %pd after coo failed (%d), ignored\n",
dentry, err);
err = 0;
}
goto out_parent; /* success */
out_dgrade:
di_downgrade_lock(parent, AuLock_IR);
out_parent:
di_read_unlock(parent, AuLock_IR);
dput(parent);
out:
AuTraceErr(err);
return err;
}
int au_do_open(struct file *file, struct au_do_open_args *args)
{
int err, no_lock = args->no_lock;
struct dentry *dentry;
struct au_finfo *finfo;
if (!no_lock)
err = au_finfo_init(file, args->fidir);
else {
lockdep_off();
err = au_finfo_init(file, args->fidir);
lockdep_on();
}
if (unlikely(err))
goto out;
dentry = file->f_path.dentry;
AuDebugOn(IS_ERR_OR_NULL(dentry));
if (!no_lock) {
di_write_lock_child(dentry);
err = au_cmoo(dentry);
di_downgrade_lock(dentry, AuLock_IR);
if (!err)
err = args->open(file, vfsub_file_flags(file), NULL);
di_read_unlock(dentry, AuLock_IR);
} else {
err = au_cmoo(dentry);
if (!err)
err = args->open(file, vfsub_file_flags(file),
args->h_file);
if (!err && au_fbtop(file) != au_dbtop(dentry))
/*
* cmoo happens after h_file was opened.
* need to refresh file later.
*/
atomic_dec(&au_fi(file)->fi_generation);
}
finfo = au_fi(file);
if (!err) {
finfo->fi_file = file;
au_sphl_add(&finfo->fi_hlist,
&au_sbi(file->f_path.dentry->d_sb)->si_files);
}
if (!no_lock)
fi_write_unlock(file);
else {
lockdep_off();
fi_write_unlock(file);
lockdep_on();
}
if (unlikely(err)) {
finfo->fi_hdir = NULL;
au_finfo_fin(file, /*atonce*/0);
}
out:
return err;
}
int au_reopen_nondir(struct file *file)
{
int err;
aufs_bindex_t btop;
struct dentry *dentry;
struct file *h_file, *h_file_tmp;
dentry = file->f_path.dentry;
btop = au_dbtop(dentry);
h_file_tmp = NULL;
if (au_fbtop(file) == btop) {
h_file = au_hf_top(file);
if (file->f_mode == h_file->f_mode)
return 0; /* success */
h_file_tmp = h_file;
get_file(h_file_tmp);
au_set_h_fptr(file, btop, NULL);
}
AuDebugOn(au_fi(file)->fi_hdir);
/*
* it can happen
* file exists on both of rw and ro
* open --> dbtop and fbtop are both 0
* prepend a branch as rw, "rw" become ro
* remove rw/file
* delete the top branch, "rw" becomes rw again
* --> dbtop is 1, fbtop is still 0
* write --> fbtop is 0 but dbtop is 1
*/
/* AuDebugOn(au_fbtop(file) < btop); */
h_file = au_h_open(dentry, btop, vfsub_file_flags(file) & ~O_TRUNC,
file, /*force_wr*/0);
err = PTR_ERR(h_file);
if (IS_ERR(h_file)) {
if (h_file_tmp) {
au_sbr_get(dentry->d_sb, btop);
au_set_h_fptr(file, btop, h_file_tmp);
h_file_tmp = NULL;
}
goto out; /* todo: close all? */
}
err = 0;
au_set_fbtop(file, btop);
au_set_h_fptr(file, btop, h_file);
au_update_figen(file);
/* todo: necessary? */
/* file->f_ra = h_file->f_ra; */
out:
if (h_file_tmp)
fput(h_file_tmp);
return err;
}
/* ---------------------------------------------------------------------- */
static int au_reopen_wh(struct file *file, aufs_bindex_t btgt,
struct dentry *hi_wh)
{
int err;
aufs_bindex_t btop;
struct au_dinfo *dinfo;
struct dentry *h_dentry;
struct au_hdentry *hdp;
dinfo = au_di(file->f_path.dentry);
AuRwMustWriteLock(&dinfo->di_rwsem);
btop = dinfo->di_btop;
dinfo->di_btop = btgt;
hdp = au_hdentry(dinfo, btgt);
h_dentry = hdp->hd_dentry;
hdp->hd_dentry = hi_wh;
err = au_reopen_nondir(file);
hdp->hd_dentry = h_dentry;
dinfo->di_btop = btop;
return err;
}
static int au_ready_to_write_wh(struct file *file, loff_t len,
aufs_bindex_t bcpup, struct au_pin *pin)
{
int err;
struct inode *inode, *h_inode;
struct dentry *h_dentry, *hi_wh;
struct au_cp_generic cpg = {
.dentry = file->f_path.dentry,
.bdst = bcpup,
.bsrc = -1,
.len = len,
.pin = pin
};
au_update_dbtop(cpg.dentry);
inode = d_inode(cpg.dentry);
h_inode = NULL;
if (au_dbtop(cpg.dentry) <= bcpup
&& au_dbbot(cpg.dentry) >= bcpup) {
h_dentry = au_h_dptr(cpg.dentry, bcpup);
if (h_dentry && d_is_positive(h_dentry))
h_inode = d_inode(h_dentry);
}
hi_wh = au_hi_wh(inode, bcpup);
if (!hi_wh && !h_inode)
err = au_sio_cpup_wh(&cpg, file);
else
/* already copied-up after unlink */
err = au_reopen_wh(file, bcpup, hi_wh);
if (!err
&& (inode->i_nlink > 1
|| (inode->i_state & I_LINKABLE))
&& au_opt_test(au_mntflags(cpg.dentry->d_sb), PLINK))
au_plink_append(inode, bcpup, au_h_dptr(cpg.dentry, bcpup));
return err;
}
/*
* prepare the @file for writing.
*/
int au_ready_to_write(struct file *file, loff_t len, struct au_pin *pin)
{
int err;
aufs_bindex_t dbtop;
struct dentry *parent;
struct inode *inode;
struct super_block *sb;
struct file *h_file;
struct au_cp_generic cpg = {
.dentry = file->f_path.dentry,
.bdst = -1,
.bsrc = -1,
.len = len,
.pin = pin,
.flags = AuCpup_DTIME
};
sb = cpg.dentry->d_sb;
inode = d_inode(cpg.dentry);
cpg.bsrc = au_fbtop(file);
err = au_test_ro(sb, cpg.bsrc, inode);
if (!err && (au_hf_top(file)->f_mode & FMODE_WRITE)) {
err = au_pin(pin, cpg.dentry, cpg.bsrc, AuOpt_UDBA_NONE,
/*flags*/0);
goto out;
}
/* need to cpup or reopen */
parent = dget_parent(cpg.dentry);
di_write_lock_parent(parent);
err = AuWbrCopyup(au_sbi(sb), cpg.dentry);
cpg.bdst = err;
if (unlikely(err < 0))
goto out_dgrade;
err = 0;
if (!d_unhashed(cpg.dentry) && !au_h_dptr(parent, cpg.bdst)) {
err = au_cpup_dirs(cpg.dentry, cpg.bdst);
if (unlikely(err))
goto out_dgrade;
}
err = au_pin(pin, cpg.dentry, cpg.bdst, AuOpt_UDBA_NONE,
AuPin_DI_LOCKED | AuPin_MNT_WRITE);
if (unlikely(err))
goto out_dgrade;
dbtop = au_dbtop(cpg.dentry);
if (dbtop <= cpg.bdst)
cpg.bsrc = cpg.bdst;
if (dbtop <= cpg.bdst /* just reopen */
|| !d_unhashed(cpg.dentry) /* copyup and reopen */
) {
h_file = au_h_open_pre(cpg.dentry, cpg.bsrc, /*force_wr*/0);
if (IS_ERR(h_file))
err = PTR_ERR(h_file);
else {
di_downgrade_lock(parent, AuLock_IR);
if (dbtop > cpg.bdst)
err = au_sio_cpup_simple(&cpg);
if (!err)
err = au_reopen_nondir(file);
au_h_open_post(cpg.dentry, cpg.bsrc, h_file);
}
} else { /* copyup as wh and reopen */
/*
* since writable hfsplus branch is not supported,
* h_open_pre/post() are unnecessary.
*/
err = au_ready_to_write_wh(file, len, cpg.bdst, pin);
di_downgrade_lock(parent, AuLock_IR);
}
if (!err) {
au_pin_set_parent_lflag(pin, /*lflag*/0);
goto out_dput; /* success */
}
au_unpin(pin);
goto out_unlock;
out_dgrade:
di_downgrade_lock(parent, AuLock_IR);
out_unlock:
di_read_unlock(parent, AuLock_IR);
out_dput:
dput(parent);
out:
return err;
}
/* ---------------------------------------------------------------------- */
int au_do_flush(struct file *file, fl_owner_t id,
int (*flush)(struct file *file, fl_owner_t id))
{
int err;
struct super_block *sb;
struct inode *inode;
inode = file_inode(file);
sb = inode->i_sb;
si_noflush_read_lock(sb);
fi_read_lock(file);
ii_read_lock_child(inode);
err = flush(file, id);
au_cpup_attr_timesizes(inode);
ii_read_unlock(inode);
fi_read_unlock(file);
si_read_unlock(sb);
return err;
}
/* ---------------------------------------------------------------------- */
static int au_file_refresh_by_inode(struct file *file, int *need_reopen)
{
int err;
struct au_pin pin;
struct au_finfo *finfo;
struct dentry *parent, *hi_wh;
struct inode *inode;
struct super_block *sb;
struct au_cp_generic cpg = {
.dentry = file->f_path.dentry,
.bdst = -1,
.bsrc = -1,
.len = -1,
.pin = &pin,
.flags = AuCpup_DTIME
};
FiMustWriteLock(file);
err = 0;
finfo = au_fi(file);
sb = cpg.dentry->d_sb;
inode = d_inode(cpg.dentry);
cpg.bdst = au_ibtop(inode);
if (cpg.bdst == finfo->fi_btop || IS_ROOT(cpg.dentry))
goto out;
parent = dget_parent(cpg.dentry);
if (au_test_ro(sb, cpg.bdst, inode)) {
di_read_lock_parent(parent, !AuLock_IR);
err = AuWbrCopyup(au_sbi(sb), cpg.dentry);
cpg.bdst = err;
di_read_unlock(parent, !AuLock_IR);
if (unlikely(err < 0))
goto out_parent;
err = 0;
}
di_read_lock_parent(parent, AuLock_IR);
hi_wh = au_hi_wh(inode, cpg.bdst);
if (!S_ISDIR(inode->i_mode)
&& au_opt_test(au_mntflags(sb), PLINK)
&& au_plink_test(inode)
&& !d_unhashed(cpg.dentry)
&& cpg.bdst < au_dbtop(cpg.dentry)) {
err = au_test_and_cpup_dirs(cpg.dentry, cpg.bdst);
if (unlikely(err))
goto out_unlock;
/* always superio. */
err = au_pin(&pin, cpg.dentry, cpg.bdst, AuOpt_UDBA_NONE,
AuPin_DI_LOCKED | AuPin_MNT_WRITE);
if (!err) {
err = au_sio_cpup_simple(&cpg);
au_unpin(&pin);
}
} else if (hi_wh) {
/* already copied-up after unlink */
err = au_reopen_wh(file, cpg.bdst, hi_wh);
*need_reopen = 0;
}
out_unlock:
di_read_unlock(parent, AuLock_IR);
out_parent:
dput(parent);
out:
return err;
}
static void au_do_refresh_dir(struct file *file)
{
int execed;
aufs_bindex_t bindex, bbot, new_bindex, brid;
struct au_hfile *p, tmp, *q;
struct au_finfo *finfo;
struct super_block *sb;
struct au_fidir *fidir;
FiMustWriteLock(file);
sb = file->f_path.dentry->d_sb;
finfo = au_fi(file);
fidir = finfo->fi_hdir;
AuDebugOn(!fidir);
p = fidir->fd_hfile + finfo->fi_btop;
brid = p->hf_br->br_id;
bbot = fidir->fd_bbot;
for (bindex = finfo->fi_btop; bindex <= bbot; bindex++, p++) {
if (!p->hf_file)
continue;
new_bindex = au_br_index(sb, p->hf_br->br_id);
if (new_bindex == bindex)
continue;
if (new_bindex < 0) {
au_set_h_fptr(file, bindex, NULL);
continue;
}
/* swap two lower inode, and loop again */
q = fidir->fd_hfile + new_bindex;
tmp = *q;
*q = *p;
*p = tmp;
if (tmp.hf_file) {
bindex--;
p--;
}
}
execed = vfsub_file_execed(file);
p = fidir->fd_hfile;
if (!au_test_mmapped(file) && !d_unlinked(file->f_path.dentry)) {
bbot = au_sbbot(sb);
for (finfo->fi_btop = 0; finfo->fi_btop <= bbot;
finfo->fi_btop++, p++)
if (p->hf_file) {
if (file_inode(p->hf_file))
break;
au_hfput(p, execed);
}
} else {
bbot = au_br_index(sb, brid);
for (finfo->fi_btop = 0; finfo->fi_btop < bbot;
finfo->fi_btop++, p++)
if (p->hf_file)
au_hfput(p, execed);
bbot = au_sbbot(sb);
}
p = fidir->fd_hfile + bbot;
for (fidir->fd_bbot = bbot; fidir->fd_bbot >= finfo->fi_btop;
fidir->fd_bbot--, p--)
if (p->hf_file) {
if (file_inode(p->hf_file))
break;
au_hfput(p, execed);
}
AuDebugOn(fidir->fd_bbot < finfo->fi_btop);
}
/*
* after branch manipulating, refresh the file.
*/
static int refresh_file(struct file *file, int (*reopen)(struct file *file))
{
int err, need_reopen, nbr;
aufs_bindex_t bbot, bindex;
struct dentry *dentry;
struct super_block *sb;
struct au_finfo *finfo;
struct au_hfile *hfile;
dentry = file->f_path.dentry;
sb = dentry->d_sb;
nbr = au_sbbot(sb) + 1;
finfo = au_fi(file);
if (!finfo->fi_hdir) {
hfile = &finfo->fi_htop;
AuDebugOn(!hfile->hf_file);
bindex = au_br_index(sb, hfile->hf_br->br_id);
AuDebugOn(bindex < 0);
if (bindex != finfo->fi_btop)
au_set_fbtop(file, bindex);
} else {
err = au_fidir_realloc(finfo, nbr, /*may_shrink*/0);
if (unlikely(err))
goto out;
au_do_refresh_dir(file);
}
err = 0;
need_reopen = 1;
if (!au_test_mmapped(file))
err = au_file_refresh_by_inode(file, &need_reopen);
if (finfo->fi_hdir)
/* harmless if err */
au_fidir_realloc(finfo, nbr, /*may_shrink*/1);
if (!err && need_reopen && !d_unlinked(dentry))
err = reopen(file);
if (!err) {
au_update_figen(file);
goto out; /* success */
}
/* error, close all lower files */
if (finfo->fi_hdir) {
bbot = au_fbbot_dir(file);
for (bindex = au_fbtop(file); bindex <= bbot; bindex++)
au_set_h_fptr(file, bindex, NULL);
}
out:
return err;
}
/* common function to regular file and dir */
int au_reval_and_lock_fdi(struct file *file, int (*reopen)(struct file *file),
int wlock)
{
int err;
unsigned int sigen, figen;
aufs_bindex_t btop;
unsigned char pseudo_link;
struct dentry *dentry;
struct inode *inode;
err = 0;
dentry = file->f_path.dentry;
inode = d_inode(dentry);
sigen = au_sigen(dentry->d_sb);
fi_write_lock(file);
figen = au_figen(file);
di_write_lock_child(dentry);
btop = au_dbtop(dentry);
pseudo_link = (btop != au_ibtop(inode));
if (sigen == figen && !pseudo_link && au_fbtop(file) == btop) {
if (!wlock) {
di_downgrade_lock(dentry, AuLock_IR);
fi_downgrade_lock(file);
}
goto out; /* success */
}
AuDbg("sigen %d, figen %d\n", sigen, figen);
if (au_digen_test(dentry, sigen)) {
err = au_reval_dpath(dentry, sigen);
AuDebugOn(!err && au_digen_test(dentry, sigen));
}
if (!err)
err = refresh_file(file, reopen);
if (!err) {
if (!wlock) {
di_downgrade_lock(dentry, AuLock_IR);
fi_downgrade_lock(file);
}
} else {
di_write_unlock(dentry);
fi_write_unlock(file);
}
out:
return err;
}
/* ---------------------------------------------------------------------- */
/* cf. aufs_nopage() */
/* for madvise(2) */
static int aufs_readpage(struct file *file __maybe_unused, struct page *page)
{
unlock_page(page);
return 0;
}
/* it will never be called, but necessary to support O_DIRECT */
static ssize_t aufs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
{ BUG(); return 0; }
/* they will never be called. */
#ifdef CONFIG_AUFS_DEBUG
static int aufs_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
{ AuUnsupport(); return 0; }
static int aufs_write_end(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned copied,
struct page *page, void *fsdata)
{ AuUnsupport(); return 0; }
static int aufs_writepage(struct page *page, struct writeback_control *wbc)
{ AuUnsupport(); return 0; }
static int aufs_set_page_dirty(struct page *page)
{ AuUnsupport(); return 0; }
static void aufs_invalidatepage(struct page *page, unsigned int offset,
unsigned int length)
{ AuUnsupport(); }
static int aufs_releasepage(struct page *page, gfp_t gfp)
{ AuUnsupport(); return 0; }
#if 0 /* called by memory compaction regardless file */
static int aufs_migratepage(struct address_space *mapping, struct page *newpage,
struct page *page, enum migrate_mode mode)
{ AuUnsupport(); return 0; }
#endif
static bool aufs_isolate_page(struct page *page, isolate_mode_t mode)
{ AuUnsupport(); return true; }
static void aufs_putback_page(struct page *page)
{ AuUnsupport(); }
static int aufs_launder_page(struct page *page)
{ AuUnsupport(); return 0; }
static int aufs_is_partially_uptodate(struct page *page,
unsigned long from,
unsigned long count)
{ AuUnsupport(); return 0; }
static void aufs_is_dirty_writeback(struct page *page, bool *dirty,
bool *writeback)
{ AuUnsupport(); }
static int aufs_error_remove_page(struct address_space *mapping,
struct page *page)
{ AuUnsupport(); return 0; }
static int aufs_swap_activate(struct swap_info_struct *sis, struct file *file,
sector_t *span)
{ AuUnsupport(); return 0; }
static void aufs_swap_deactivate(struct file *file)
{ AuUnsupport(); }
#endif /* CONFIG_AUFS_DEBUG */
const struct address_space_operations aufs_aop = {
.readpage = aufs_readpage,
.direct_IO = aufs_direct_IO,
#ifdef CONFIG_AUFS_DEBUG
.writepage = aufs_writepage,
/* no writepages, because of writepage */
.set_page_dirty = aufs_set_page_dirty,
/* no readpages, because of readpage */
.write_begin = aufs_write_begin,
.write_end = aufs_write_end,
/* no bmap, no block device */
.invalidatepage = aufs_invalidatepage,
.releasepage = aufs_releasepage,
/* is fallback_migrate_page ok? */
/* .migratepage = aufs_migratepage, */
.isolate_page = aufs_isolate_page,
.putback_page = aufs_putback_page,
.launder_page = aufs_launder_page,
.is_partially_uptodate = aufs_is_partially_uptodate,
.is_dirty_writeback = aufs_is_dirty_writeback,
.error_remove_page = aufs_error_remove_page,
.swap_activate = aufs_swap_activate,
.swap_deactivate = aufs_swap_deactivate
#endif /* CONFIG_AUFS_DEBUG */
};
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