/*
* decide the branch and the parent dir where we will create a new entry.
* returns new bindex or an error.
* copyup the parent dir if needed.
*/
int au_wr_dir(struct dentry *dentry, struct dentry *src_dentry,
struct au_wr_dir_args *args)
{
int err;
aufs_bindex_t bcpup, bstart, src_bstart;
const unsigned char add_entry = !!au_ftest_wrdir(args->flags,
ADD_ENTRY);
struct super_block *sb;
struct dentry *parent;
struct au_sbinfo *sbinfo;
sb = dentry->d_sb;
sbinfo = au_sbi(sb);
parent = dget_parent(dentry);
bstart = au_dbstart(dentry);
bcpup = bstart;
if (args->force_btgt < 0) {
if (src_dentry) {
src_bstart = au_dbstart(src_dentry);
if (src_bstart < bstart)
bcpup = src_bstart;
} else if (add_entry) {
err = AuWbrCreate(sbinfo, dentry,
au_ftest_wrdir(args->flags, ISDIR));
bcpup = err;
}
if (bcpup < 0 || au_test_ro(sb, bcpup, dentry->d_inode)) {
if (add_entry)
err = AuWbrCopyup(sbinfo, dentry);
else {
if (!IS_ROOT(dentry)) {
di_read_lock_parent(parent, !AuLock_IR);
err = AuWbrCopyup(sbinfo, dentry);
di_read_unlock(parent, !AuLock_IR);
} else
err = AuWbrCopyup(sbinfo, dentry);
}
bcpup = err;
if (unlikely(err < 0))
goto out;
}
} else {
bcpup = args->force_btgt;
AuDebugOn(au_test_ro(sb, bcpup, dentry->d_inode));
}
AuDbg("bstart %d, bcpup %d\n", bstart, bcpup);
err = bcpup;
if (bcpup == bstart)
goto out; /* success */
else if (bstart < bcpup)
au_update_dbrange(dentry, /*do_put_zero*/1);
/* copyup the new parent into the branch we process */
err = au_wr_dir_cpup(dentry, parent, add_entry, bcpup, bstart);
out:
dput(parent);
return err;
}
/*
* decide if a new whiteout for @dentry is necessary or not.
* when it is necessary, prepare the parent dir for the upper branch whose
* branch index is @bcpup for creation. the actual creation of the whiteout will
* be done by caller.
* return value:
* 0: wh is unnecessary
* plus: wh is necessary
* minus: error
*/
int au_wr_dir_need_wh(struct dentry *dentry, int isdir, aufs_bindex_t *bcpup)
{
int need_wh, err;
aufs_bindex_t bstart;
struct super_block *sb;
sb = dentry->d_sb;
bstart = au_dbstart(dentry);
if (*bcpup < 0) {
*bcpup = bstart;
if (au_test_ro(sb, bstart, dentry->d_inode)) {
err = AuWbrCopyup(au_sbi(sb), dentry);
*bcpup = err;
if (unlikely(err < 0))
goto out;
}
} else
AuDebugOn(bstart < *bcpup
|| au_test_ro(sb, *bcpup, dentry->d_inode));
AuDbg("bcpup %d, bstart %d\n", *bcpup, bstart);
if (*bcpup != bstart) {
err = au_cpup_dirs(dentry, *bcpup);
if (unlikely(err))
goto out;
need_wh = 1;
} else {
aufs_bindex_t old_bend, new_bend, bdiropq = -1;
old_bend = au_dbend(dentry);
if (isdir) {
bdiropq = au_dbdiropq(dentry);
au_set_dbdiropq(dentry, -1);
}
need_wh = au_lkup_dentry(dentry, bstart + 1, /*type*/0,
/*nd*/NULL);
err = need_wh;
if (isdir)
au_set_dbdiropq(dentry, bdiropq);
if (unlikely(err < 0))
goto out;
new_bend = au_dbend(dentry);
if (!need_wh && old_bend != new_bend) {
au_set_h_dptr(dentry, new_bend, NULL);
au_set_dbend(dentry, old_bend);
}
}
AuDbg("need_wh %d\n", need_wh);
err = need_wh;
out:
return err;
}
/*
* decide if a new whiteout for @dentry is necessary or not.
* when it is necessary, prepare the parent dir for the upper branch whose
* branch index is @bcpup for creation. the actual creation of the whiteout will
* be done by caller.
* return value:
* 0: wh is unnecessary
* plus: wh is necessary
* minus: error
*/
int au_wr_dir_need_wh(struct dentry *dentry, int isdir, aufs_bindex_t *bcpup)
{
int need_wh, err;
aufs_bindex_t bstart;
struct super_block *sb;
sb = dentry->d_sb;
bstart = au_dbstart(dentry);
if (*bcpup < 0) {
*bcpup = bstart;
if (au_test_ro(sb, bstart, dentry->d_inode)) {
err = AuWbrCopyup(au_sbi(sb), dentry);
*bcpup = err;
if (unlikely(err < 0))
goto out;
}
} else
AuDebugOn(bstart < *bcpup
|| au_test_ro(sb, *bcpup, dentry->d_inode));
AuDbg("bcpup %d, bstart %d\n", *bcpup, bstart);
if (*bcpup != bstart) {
err = au_cpup_dirs(dentry, *bcpup);
if (unlikely(err))
goto out;
need_wh = 1;
} else {
struct au_dinfo *dinfo, *tmp;
need_wh = -ENOMEM;
dinfo = au_di(dentry);
tmp = au_di_alloc(sb, AuLsc_DI_TMP);
if (tmp) {
au_di_cp(tmp, dinfo);
au_di_swap(tmp, dinfo);
/* returns the number of positive dentries */
need_wh = au_lkup_dentry(dentry, bstart + 1, /*type*/0,
/*nd*/NULL);
au_di_swap(tmp, dinfo);
au_rw_write_unlock(&tmp->di_rwsem);
au_di_free(tmp);
}
}
AuDbg("need_wh %d\n", need_wh);
err = need_wh;
out:
return err;
}
int au_do_open_nondir(struct file *file, int flags)
{
int err;
aufs_bindex_t bindex;
struct file *h_file;
struct dentry *dentry;
struct au_finfo *finfo;
FiMustWriteLock(file);
err = 0;
dentry = file->f_dentry;
finfo = au_fi(file);
memset(&finfo->fi_htop, 0, sizeof(finfo->fi_htop));
finfo->fi_hvmop = NULL;
bindex = au_dbstart(dentry);
/* O_TRUNC is processed already */
BUG_ON(au_test_ro(dentry->d_sb, bindex, dentry->d_inode)
&& (flags & O_TRUNC));
h_file = au_h_open(dentry, bindex, flags, file);
if (IS_ERR(h_file))
err = PTR_ERR(h_file);
else {
au_set_fbstart(file, bindex);
au_set_h_fptr(file, bindex, h_file);
au_update_figen(file);
/* todo: necessary? */
/* file->f_ra = h_file->f_ra; */
}
return err;
}
int au_do_open_nondir(struct file *file, int flags)
{
int err;
aufs_bindex_t bindex;
struct file *h_file;
struct dentry *dentry;
struct au_finfo *finfo;
FiMustWriteLock(file);
dentry = file->f_dentry;
err = au_d_alive(dentry);
if (unlikely(err))
goto out;
finfo = au_fi(file);
memset(&finfo->fi_htop, 0, sizeof(finfo->fi_htop));
finfo->fi_hvmop = NULL;
bindex = au_dbstart(dentry);
/*
* O_TRUNC is processed already.
* But it is legal the target file has its size, since someone else may
* give it while we are opening.
*/
BUG_ON(0 && au_test_ro(dentry->d_sb, bindex, dentry->d_inode)
&& (flags & O_TRUNC));
h_file = au_h_open(dentry, bindex, flags, file);
if (IS_ERR(h_file))
err = PTR_ERR(h_file);
else {
au_set_fbstart(file, bindex);
au_set_h_fptr(file, bindex, h_file);
au_update_figen(file);
/* todo: necessary? */
/* file->f_ra = h_file->f_ra; */
}
out:
return err;
}
/* common functions to regular file and dir */
struct file *au_h_open(struct dentry *dentry, aufs_bindex_t bindex, int flags,
struct file *file)
{
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, exec_flag;
/* 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)
goto out;
h_inode = h_dentry->d_inode;
if (au_test_nfsd() && !h_inode)
goto out;
spin_lock(&h_dentry->d_lock);
err = (!d_unhashed(dentry) && d_unlinked(h_dentry))
|| !h_inode
/* || !dentry->d_inode->i_nlink */
;
spin_unlock(&h_dentry->d_lock);
if (unlikely(err))
goto out;
sb = dentry->d_sb;
br = au_sbr(sb, bindex);
h_file = ERR_PTR(-EACCES);
exec_flag = flags & __FMODE_EXEC;
if (exec_flag && (br->br_mnt->mnt_flags & MNT_NOEXEC))
goto out;
/* drop flags for writing */
if (au_test_ro(sb, bindex, dentry->d_inode))
flags = au_file_roflags(flags);
flags &= ~O_CREAT;
atomic_inc(&br->br_count);
h_path.dentry = h_dentry;
h_path.mnt = br->br_mnt;
if (!au_special_file(h_inode->i_mode))
h_file = vfsub_dentry_open(&h_path, flags);
else {
/* this block depends upon the configuration */
di_read_unlock(dentry, AuLock_IR);
fi_write_unlock(file);
si_read_unlock(sb);
h_file = vfsub_dentry_open(&h_path, flags);
si_noflush_read_lock(sb);
fi_write_lock(file);
di_read_lock_child(dentry, AuLock_IR);
}
if (IS_ERR(h_file))
goto out_br;
if (exec_flag) {
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:
atomic_dec(&br->br_count);
out:
return h_file;
}
static int au_file_refresh_by_inode(struct file *file, int *need_reopen)
{
int err;
aufs_bindex_t bstart;
struct au_pin pin;
struct au_finfo *finfo;
struct dentry *dentry, *parent, *hi_wh;
struct inode *inode;
struct super_block *sb;
FiMustWriteLock(file);
err = 0;
finfo = au_fi(file);
dentry = file->f_dentry;
sb = dentry->d_sb;
inode = dentry->d_inode;
bstart = au_ibstart(inode);
if (bstart == finfo->fi_btop || IS_ROOT(dentry))
goto out;
parent = dget_parent(dentry);
if (au_test_ro(sb, bstart, inode)) {
di_read_lock_parent(parent, !AuLock_IR);
err = AuWbrCopyup(au_sbi(sb), dentry);
bstart = 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, bstart);
if (!S_ISDIR(inode->i_mode)
&& au_opt_test(au_mntflags(sb), PLINK)
&& au_plink_test(inode)
&& !d_unhashed(dentry)) {
err = au_test_and_cpup_dirs(dentry, bstart);
if (unlikely(err))
goto out_unlock;
/* always superio. */
err = au_pin(&pin, dentry, bstart, AuOpt_UDBA_NONE,
AuPin_DI_LOCKED | AuPin_MNT_WRITE);
if (!err)
err = au_sio_cpup_simple(dentry, bstart, -1,
AuCpup_DTIME);
au_unpin(&pin);
} else if (hi_wh) {
/* already copied-up after unlink */
err = au_reopen_wh(file, bstart, hi_wh);
*need_reopen = 0;
}
out_unlock:
di_read_unlock(parent, AuLock_IR);
out_parent:
dput(parent);
out:
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 bstart, bcpup, dbstart;
struct dentry *dentry, *parent, *h_dentry;
struct inode *h_inode, *inode;
struct super_block *sb;
struct file *h_file;
dentry = file->f_dentry;
sb = dentry->d_sb;
inode = dentry->d_inode;
AuDebugOn(au_special_file(inode->i_mode));
bstart = au_fbstart(file);
err = au_test_ro(sb, bstart, inode);
if (!err && (au_hf_top(file)->f_mode & FMODE_WRITE)) {
err = au_pin(pin, dentry, bstart, AuOpt_UDBA_NONE, /*flags*/0);
goto out;
}
/* need to cpup or reopen */
parent = dget_parent(dentry);
di_write_lock_parent(parent);
err = AuWbrCopyup(au_sbi(sb), dentry);
bcpup = err;
if (unlikely(err < 0))
goto out_dgrade;
err = 0;
if (!d_unhashed(dentry) && !au_h_dptr(parent, bcpup)) {
err = au_cpup_dirs(dentry, bcpup);
if (unlikely(err))
goto out_dgrade;
}
err = au_pin(pin, dentry, bcpup, AuOpt_UDBA_NONE,
AuPin_DI_LOCKED | AuPin_MNT_WRITE);
if (unlikely(err))
goto out_dgrade;
h_dentry = au_hf_top(file)->f_dentry;
h_inode = h_dentry->d_inode;
dbstart = au_dbstart(dentry);
if (dbstart <= bcpup) {
h_dentry = au_h_dptr(dentry, bcpup);
AuDebugOn(!h_dentry);
h_inode = h_dentry->d_inode;
AuDebugOn(!h_inode);
bstart = bcpup;
}
if (dbstart <= bcpup /* just reopen */
|| !d_unhashed(dentry) /* copyup and reopen */
) {
mutex_lock_nested(&h_inode->i_mutex, AuLsc_I_CHILD);
h_file = au_h_open_pre(dentry, bstart);
if (IS_ERR(h_file)) {
err = PTR_ERR(h_file);
h_file = NULL;
} else {
di_downgrade_lock(parent, AuLock_IR);
if (dbstart > bcpup)
err = au_sio_cpup_simple(dentry, bcpup, len,
AuCpup_DTIME);
if (!err)
err = au_reopen_nondir(file);
}
mutex_unlock(&h_inode->i_mutex);
au_h_open_post(dentry, bstart, h_file);
} else { /* copyup as wh and reopen */
/*
* since writable hfsplus branch is not supported,
* h_open_pre/post() are unnecessary.
*/
mutex_lock_nested(&h_inode->i_mutex, AuLsc_I_CHILD);
err = au_ready_to_write_wh(file, len, bcpup);
di_downgrade_lock(parent, AuLock_IR);
mutex_unlock(&h_inode->i_mutex);
}
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;
}
},
{
.bindex = bdst,
.flags = O_WRONLY | O_NOATIME | O_LARGEFILE,
.file = NULL,
.label = &&out_src_file,
.label_file = &&out_dst_file
}
};
LKTRTrace("dentry %.*s, bdst %d, bsrc %d, len %lld\n",
AuDLNPair(dentry), bdst, bsrc, len);
AuDebugOn(bsrc <= bdst);
AuDebugOn(!len);
sb = dentry->d_sb;
AuDebugOn(au_test_ro(sb, bdst, dentry->d_inode));
/* bsrc branch can be ro/rw. */
h = hidden;
for (i = 0; i < 2; i++, h++) {
h->dentry = au_h_dptr(dentry, h->bindex);
AuDebugOn(!h->dentry);
h_inode = h->dentry->d_inode;
AuDebugOn(!h_inode || !S_ISREG(h_inode->i_mode));
h->file = au_h_open(dentry, h->bindex, h->flags, /*file*/NULL);
err = PTR_ERR(h->file);
if (IS_ERR(h->file))
goto *h->label;
err = -EINVAL;
if (unlikely(!h->file->f_op))
goto *h->label_file;
/*
* 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 bstart, bcpup;
struct dentry *dentry, *parent, *h_dentry;
struct inode *h_inode, *inode;
struct super_block *sb;
dentry = file->f_dentry;
sb = dentry->d_sb;
inode = dentry->d_inode;
AuDebugOn(au_special_file(inode->i_mode));
bstart = au_fbstart(file);
err = au_test_ro(sb, bstart, inode);
if (!err && (au_h_fptr(file, bstart)->f_mode & FMODE_WRITE)) {
err = au_pin(pin, dentry, bstart, AuOpt_UDBA_NONE, /*flags*/0);
goto out;
}
/* need to cpup */
parent = dget_parent(dentry);
di_write_lock_parent(parent);
err = AuWbrCopyup(au_sbi(sb), dentry);
bcpup = err;
if (unlikely(err < 0))
goto out_dgrade;
err = 0;
if (!au_h_dptr(parent, bcpup)) {
err = au_cpup_dirs(dentry, bcpup);
if (unlikely(err))
goto out_dgrade;
}
err = au_pin(pin, dentry, bcpup, AuOpt_UDBA_NONE,
AuPin_DI_LOCKED | AuPin_MNT_WRITE);
if (unlikely(err))
goto out_dgrade;
h_dentry = au_h_fptr(file, bstart)->f_dentry;
h_inode = h_dentry->d_inode;
mutex_lock_nested(&h_inode->i_mutex, AuLsc_I_CHILD);
if (d_unhashed(dentry) /* || d_unhashed(h_dentry) */
/* || !h_inode->i_nlink */) {
err = au_ready_to_write_wh(file, len, bcpup);
di_downgrade_lock(parent, AuLock_IR);
} else {
di_downgrade_lock(parent, AuLock_IR);
if (!au_h_dptr(dentry, bcpup))
err = au_sio_cpup_simple(dentry, bcpup, len,
AuCpup_DTIME);
if (!err)
err = au_reopen_nondir(file);
}
mutex_unlock(&h_inode->i_mutex);
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;
}
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_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 = cpg.dentry->d_inode;
cpg.bdst = au_ibstart(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_dbstart(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)
{
aufs_bindex_t bindex, bend, 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_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;
bend = fidir->fd_bbot;
for (bindex = finfo->fi_btop; bindex <= bend; 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--;
}
}
p = fidir->fd_hfile;
if (!au_test_mmapped(file) && !d_unlinked(file->f_dentry)) {
bend = au_sbend(sb);
for (finfo->fi_btop = 0; finfo->fi_btop <= bend;
finfo->fi_btop++, p++)
if (p->hf_file) {
if (file_inode(p->hf_file))
break;
else
au_hfput(p, file);
}
} else {
bend = au_br_index(sb, brid);
for (finfo->fi_btop = 0; finfo->fi_btop < bend;
finfo->fi_btop++, p++)
if (p->hf_file)
au_hfput(p, file);
bend = au_sbend(sb);
}
p = fidir->fd_hfile + bend;
for (fidir->fd_bbot = bend; fidir->fd_bbot >= finfo->fi_btop;
fidir->fd_bbot--, p--)
if (p->hf_file) {
if (file_inode(p->hf_file))
break;
else
au_hfput(p, file);
}
AuDebugOn(fidir->fd_bbot < finfo->fi_btop);
}
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_dentry,
.bdst = bcpup,
.bsrc = -1,
.len = len,
.pin = pin
};
au_update_dbstart(cpg.dentry);
inode = cpg.dentry->d_inode;
h_inode = NULL;
if (au_dbstart(cpg.dentry) <= bcpup
&& au_dbend(cpg.dentry) >= bcpup) {
h_dentry = au_h_dptr(cpg.dentry, bcpup);
if (h_dentry)
h_inode = h_dentry->d_inode;
}
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
&& 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 dbstart;
struct dentry *parent, *h_dentry;
struct inode *inode;
struct super_block *sb;
struct file *h_file;
struct au_cp_generic cpg = {
.dentry = file->f_dentry,
.bdst = -1,
.bsrc = -1,
.len = len,
.pin = pin,
.flags = AuCpup_DTIME
};
sb = cpg.dentry->d_sb;
inode = cpg.dentry->d_inode;
AuDebugOn(au_special_file(inode->i_mode));
cpg.bsrc = au_fbstart(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;
h_dentry = au_hf_top(file)->f_dentry;
dbstart = au_dbstart(cpg.dentry);
if (dbstart <= cpg.bdst) {
h_dentry = au_h_dptr(cpg.dentry, cpg.bdst);
AuDebugOn(!h_dentry);
cpg.bsrc = cpg.bdst;
}
if (dbstart <= 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 (dbstart > 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;
}
/* 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, exec_flag;
/* 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)
goto out;
h_inode = h_dentry->d_inode;
if (au_test_nfsd() && !h_inode)
goto out;
spin_lock(&h_dentry->d_lock);
err = (!d_unhashed(dentry) && d_unlinked(h_dentry))
|| !h_inode
/* || !dentry->d_inode->i_nlink */
;
spin_unlock(&h_dentry->d_lock);
if (unlikely(err))
goto out;
sb = dentry->d_sb;
br = au_sbr(sb, bindex);
h_file = ERR_PTR(-EACCES);
exec_flag = flags & __FMODE_EXEC;
if (exec_flag && (au_br_mnt(br)->mnt_flags & MNT_NOEXEC))
goto out;
/* drop flags for writing */
if (au_test_ro(sb, bindex, dentry->d_inode)) {
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;
atomic_inc(&br->br_count);
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 (exec_flag) {
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:
atomic_dec(&br->br_count);
out:
return h_file;
}