static int au_wbr_init(struct au_branch *br, struct super_block *sb,
int perm, struct path *path)
{
int err;
struct kstatfs kst;
struct au_wbr *wbr;
struct dentry *h_dentry;
wbr = br->br_wbr;
au_rw_init(&wbr->wbr_wh_rwsem);
memset(wbr->wbr_wh, 0, sizeof(wbr->wbr_wh));
atomic_set(&wbr->wbr_wh_running, 0);
wbr->wbr_bytes = 0;
/*
* a limit for rmdir/rename a dir
* cf. AUFS_MAX_NAMELEN in include/linux/aufs_type.h
*/
h_dentry = path->dentry;
err = vfs_statfs(h_dentry, &kst);
if (unlikely(err))
goto out;
err = -EINVAL;
if (kst.f_namelen >= NAME_MAX)
err = au_br_init_wh(sb, br, perm, h_dentry);
else
pr_err("%.*s(%s), unsupported namelen %ld\n",
AuDLNPair(h_dentry), au_sbtype(h_dentry->d_sb),
kst.f_namelen);
out:
return err;
}
static int do_pri_inode(aufs_bindex_t bindex, struct inode *inode,
struct dentry *wh)
{
char *n = NULL;
int l = 0;
if (!inode || IS_ERR(inode)) {
dpri("i%d: err %ld\n", bindex, PTR_ERR(inode));
return -1;
}
/* the type of i_blocks depends upon CONFIG_LSF */
BUILD_BUG_ON(sizeof(inode->i_blocks) != sizeof(unsigned long)
&& sizeof(inode->i_blocks) != sizeof(u64));
if (wh) {
n = (void *)wh->d_name.name;
l = wh->d_name.len;
}
dpri("i%d: i%lu, %s, cnt %d, nl %u, 0%o, sz %llu, blk %llu,"
" ct %lld, np %lu, st 0x%lx, f 0x%x, v %llu, g %x%s%.*s\n",
bindex,
inode->i_ino, inode->i_sb ? au_sbtype(inode->i_sb) : "??",
atomic_read(&inode->i_count), inode->i_nlink, inode->i_mode,
i_size_read(inode), (unsigned long long)inode->i_blocks,
(long long)timespec_to_ns(&inode->i_ctime) & 0x0ffff,
inode->i_mapping ? inode->i_mapping->nrpages : 0,
inode->i_state, inode->i_flags, inode->i_version,
inode->i_generation,
l ? ", wh " : "", l, n);
return 0;
}
static int do_pri_br(aufs_bindex_t bindex, struct au_branch *br)
{
struct vfsmount *mnt;
struct super_block *sb;
if (!br || IS_ERR(br))
goto out;
mnt = br->br_mnt;
if (!mnt || IS_ERR(mnt))
goto out;
sb = mnt->mnt_sb;
if (!sb || IS_ERR(sb))
goto out;
dpri("s%d: {perm 0x%x, cnt %d, wbr %p}, "
"%s, dev 0x%02x%02x, flags 0x%lx, cnt(BIAS) %d, active %d, "
"xino %d\n",
bindex, br->br_perm, atomic_read(&br->br_count), br->br_wbr,
au_sbtype(sb), MAJOR(sb->s_dev), MINOR(sb->s_dev),
sb->s_flags, sb->s_count - S_BIAS,
atomic_read(&sb->s_active), !!br->br_xino.xi_file);
return 0;
out:
dpri("s%d: err %ld\n", bindex, PTR_ERR(br));
return -1;
}
static int do_pri_dentry(aufs_bindex_t bindex, struct dentry *dentry)
{
struct dentry *wh = NULL;
int hn;
if (!dentry || IS_ERR(dentry)) {
dpri("d%d: err %ld\n", bindex, PTR_ERR(dentry));
return -1;
}
/* do not call dget_parent() here */
/* note: access d_xxx without d_lock */
dpri("d%d: %.*s?/%.*s, %s, cnt %d, flags 0x%x\n",
bindex,
AuDLNPair(dentry->d_parent), AuDLNPair(dentry),
dentry->d_sb ? au_sbtype(dentry->d_sb) : "??",
dentry->d_count, dentry->d_flags);
hn = -1;
if (bindex >= 0 && dentry->d_inode && au_test_aufs(dentry->d_sb)) {
struct au_iinfo *iinfo = au_ii(dentry->d_inode);
if (iinfo) {
hn = !!au_hn(iinfo->ii_hinode + bindex);
wh = iinfo->ii_hinode[0 + bindex].hi_whdentry;
}
}
do_pri_inode(bindex, dentry->d_inode, hn, wh);
return 0;
}
static int test_linkable(struct dentry *h_root)
{
struct inode *h_dir = h_root->d_inode;
if (h_dir->i_op->link)
return 0;
pr_err("%.*s (%s) doesn't support link(2), use noplink and rw+nolwh\n",
AuDLNPair(h_root), au_sbtype(h_root->d_sb));
return -ENOSYS;
}
void au_warn_loopback(struct super_block *h_sb)
{
int i, new_nelem;
unsigned long *a, magic;
static DEFINE_SPINLOCK(spin);
magic = h_sb->s_magic;
spin_lock(&spin);
a = au_warn_loopback_array;
for (i = 0; i < au_warn_loopback_nelem && *a; i++)
if (a[i] == magic) {
spin_unlock(&spin);
return;
}
/* h_sb is new to us, print it */
if (i < au_warn_loopback_nelem) {
a[i] = magic;
goto pr;
}
/* expand the array */
new_nelem = au_warn_loopback_nelem + au_warn_loopback_step;
a = au_kzrealloc(au_warn_loopback_array,
au_warn_loopback_nelem * sizeof(unsigned long),
new_nelem * sizeof(unsigned long), GFP_ATOMIC,
/*may_shrink*/0);
if (a) {
au_warn_loopback_nelem = new_nelem;
au_warn_loopback_array = a;
a[i] = magic;
goto pr;
}
spin_unlock(&spin);
AuWarn1("realloc failed, ignored\n");
return;
pr:
spin_unlock(&spin);
pr_warn("you may want to try another patch for loopback file "
"on %s(0x%lx) branch\n", au_sbtype(h_sb), magic);
}
static int do_pri_dentry(aufs_bindex_t bindex, struct dentry *dentry)
{
struct dentry *wh = NULL;
if (!dentry || IS_ERR(dentry)) {
dpri("d%d: err %ld\n", bindex, PTR_ERR(dentry));
return -1;
}
/* do not call dget_parent() here */
dpri("d%d: %.*s?/%.*s, %s, cnt %d, flags 0x%x\n",
bindex,
AuDLNPair(dentry->d_parent), AuDLNPair(dentry),
dentry->d_sb ? au_sbtype(dentry->d_sb) : "??",
atomic_read(&dentry->d_count), dentry->d_flags);
if (bindex >= 0 && dentry->d_inode && au_test_aufs(dentry->d_sb)) {
struct au_iinfo *iinfo = au_ii(dentry->d_inode);
if (iinfo)
wh = iinfo->ii_hinode[0 + bindex].hi_whdentry;
}
do_pri_inode(bindex, dentry->d_inode, wh);
return 0;
}
/* todo: return with unlocked? */
struct inode *au_new_inode(struct dentry *dentry, int must_new)
{
struct inode *inode;
struct dentry *h_dentry;
struct super_block *sb;
ino_t h_ino, ino;
int err, match;
aufs_bindex_t bstart;
sb = dentry->d_sb;
bstart = au_dbstart(dentry);
h_dentry = au_h_dptr(dentry, bstart);
h_ino = h_dentry->d_inode->i_ino;
err = au_xino_read(sb, bstart, h_ino, &ino);
inode = ERR_PTR(err);
if (unlikely(err))
goto out;
new_ino:
if (!ino) {
ino = au_xino_new_ino(sb);
if (unlikely(!ino)) {
inode = ERR_PTR(-EIO);
goto out;
}
}
AuDbg("i%lu\n", (unsigned long)ino);
inode = au_iget_locked(sb, ino);
err = PTR_ERR(inode);
if (IS_ERR(inode))
goto out;
AuDbg("%lx, new %d\n", inode->i_state, !!(inode->i_state & I_NEW));
if (inode->i_state & I_NEW) {
ii_write_lock_new_child(inode);
err = set_inode(inode, dentry);
if (!err) {
unlock_new_inode(inode);
goto out; /* success */
}
ii_write_unlock(inode);
iget_failed(inode);
goto out_err;
} else if (!must_new) {
err = reval_inode(inode, dentry, &match);
if (!err)
goto out; /* success */
else if (match)
goto out_iput;
}
if (unlikely(au_test_fs_unique_ino(h_dentry->d_inode)))
AuWarn1("Warning: Un-notified UDBA or repeatedly renamed dir,"
" b%d, %s, %.*s, hi%lu, i%lu.\n",
bstart, au_sbtype(h_dentry->d_sb), AuDLNPair(dentry),
(unsigned long)h_ino, (unsigned long)ino);
ino = 0;
err = au_xino_write(sb, bstart, h_ino, /*ino*/0);
if (!err) {
iput(inode);
goto new_ino;
}
out_iput:
iput(inode);
out_err:
inode = ERR_PTR(err);
out:
return inode;
}
dst.func = src.func; \
} while (0)
#define DySetAop(func) \
DySet(func, dyaop->da_op, aufs_aop, h_aop, h_sb)
#define DySetAopForce(func) \
DySetForce(func, dyaop->da_op, aufs_aop)
static void dy_aop(struct au_dykey *key, const void *h_op,
struct super_block *h_sb __maybe_unused)
{
struct au_dyaop *dyaop = (void *)key;
const struct address_space_operations *h_aop = h_op;
DyDbgDeclare(cnt);
AuDbg("%s\n", au_sbtype(h_sb));
DySetAop(writepage);
DySetAopForce(readpage); /* force */
DySetAop(writepages);
DySetAop(set_page_dirty);
DySetAop(readpages);
DySetAop(write_begin);
DySetAop(write_end);
DySetAop(bmap);
DySetAop(invalidatepage);
DySetAop(releasepage);
DySetAop(freepage);
/* these two will be changed according to an aufs mount option */
DySetAop(direct_IO);
DySetAop(get_xip_mem);
/*
* returns:
* 0: success, the caller will add it
* plus: success, it is already unified, the caller should ignore it
* minus: error
*/
static int test_add(struct super_block *sb, struct au_opt_add *add, int remount)
{
int err;
aufs_bindex_t bend, bindex;
struct dentry *root;
struct inode *inode, *h_inode;
root = sb->s_root;
bend = au_sbend(sb);
if (unlikely(bend >= 0
&& au_find_dbindex(root, add->path.dentry) >= 0)) {
err = 1;
if (!remount) {
err = -EINVAL;
pr_err("%s duplicated\n", add->pathname);
}
goto out;
}
err = -ENOSPC; /* -E2BIG; */
if (unlikely(AUFS_BRANCH_MAX <= add->bindex
|| AUFS_BRANCH_MAX - 1 <= bend)) {
pr_err("number of branches exceeded %s\n", add->pathname);
goto out;
}
err = -EDOM;
if (unlikely(add->bindex < 0 || bend + 1 < add->bindex)) {
pr_err("bad index %d\n", add->bindex);
goto out;
}
inode = add->path.dentry->d_inode;
err = -ENOENT;
if (unlikely(!inode->i_nlink)) {
pr_err("no existence %s\n", add->pathname);
goto out;
}
err = -EINVAL;
if (unlikely(inode->i_sb == sb)) {
pr_err("%s must be outside\n", add->pathname);
goto out;
}
if (unlikely(au_test_fs_unsuppoted(inode->i_sb))) {
pr_err("unsupported filesystem, %s (%s)\n",
add->pathname, au_sbtype(inode->i_sb));
goto out;
}
err = test_br(add->path.dentry->d_inode, add->perm, add->pathname);
if (unlikely(err))
goto out;
if (bend < 0)
return 0; /* success */
err = -EINVAL;
for (bindex = 0; bindex <= bend; bindex++)
if (unlikely(test_overlap(sb, add->path.dentry,
au_h_dptr(root, bindex)))) {
pr_err("%s is overlapped\n", add->pathname);
goto out;
}
err = 0;
if (au_opt_test(au_mntflags(sb), WARN_PERM)) {
h_inode = au_h_dptr(root, 0)->d_inode;
if ((h_inode->i_mode & S_IALLUGO) != (inode->i_mode & S_IALLUGO)
|| h_inode->i_uid != inode->i_uid
|| h_inode->i_gid != inode->i_gid)
pr_warning("uid/gid/perm %s %u/%u/0%o, %u/%u/0%o\n",
add->pathname,
inode->i_uid, inode->i_gid,
(inode->i_mode & S_IALLUGO),
h_inode->i_uid, h_inode->i_gid,
(h_inode->i_mode & S_IALLUGO));
}
out:
return err;
}
static struct dentry *
aufs_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len,
int fh_type)
{
struct dentry *dentry;
__u32 *fh = fid->raw;
ino_t ino, dir_ino;
aufs_bindex_t bindex;
struct au_nfsd_si_lock nsi_lock = {
.force_lock = 0
};
dentry = ERR_PTR(-ESTALE);
/* it should never happen, but the file handle is unreliable */
if (unlikely(fh_len < Fh_tail))
goto out;
nsi_lock.sigen = fh[Fh_sigen];
nsi_lock.br_id = fh[Fh_br_id];
/* branch id may be wrapped around */
bindex = si_nfsd_read_lock(sb, &nsi_lock);
if (unlikely(bindex < 0))
goto out;
nsi_lock.force_lock = 1;
/* is this inode still cached? */
ino = decode_ino(fh + Fh_ino);
/* it should never happen */
if (unlikely(ino == AUFS_ROOT_INO))
goto out;
dir_ino = decode_ino(fh + Fh_dir_ino);
dentry = decode_by_ino(sb, ino, dir_ino);
if (IS_ERR(dentry))
goto out_unlock;
if (dentry)
goto accept;
/* is the parent dir cached? */
dentry = decode_by_dir_ino(sb, ino, dir_ino, &nsi_lock);
if (IS_ERR(dentry))
goto out_unlock;
if (dentry)
goto accept;
/* lookup path */
dentry = decode_by_path(sb, bindex, ino, fh, fh_len, &nsi_lock);
if (IS_ERR(dentry))
goto out_unlock;
if (unlikely(!dentry))
/* todo?: make it ESTALE */
goto out_unlock;
accept:
if (dentry->d_inode->i_generation == fh[Fh_igen])
goto out_unlock; /* success */
dput(dentry);
dentry = ERR_PTR(-ESTALE);
out_unlock:
si_read_unlock(sb);
out:
AuTraceErrPtr(dentry);
return dentry;
}
#if 0 /* reserved for future use */
/* support subtreecheck option */
static struct dentry *aufs_fh_to_parent(struct super_block *sb, struct fid *fid,
int fh_len, int fh_type)
{
struct dentry *parent;
__u32 *fh = fid->raw;
ino_t dir_ino;
dir_ino = decode_ino(fh + Fh_dir_ino);
parent = decode_by_ino(sb, dir_ino, 0);
if (IS_ERR(parent))
goto out;
if (!parent)
parent = decode_by_path(sb, au_br_index(sb, fh[Fh_br_id]),
dir_ino, fh, fh_len);
out:
AuTraceErrPtr(parent);
return parent;
}
#endif
/* ---------------------------------------------------------------------- */
static int aufs_encode_fh(struct dentry *dentry, __u32 *fh, int *max_len,
int connectable)
{
int err;
aufs_bindex_t bindex, bend;
struct super_block *sb, *h_sb;
struct inode *inode;
struct dentry *parent, *h_parent;
struct au_branch *br;
AuDebugOn(au_test_anon(dentry));
parent = NULL;
err = -ENOSPC;
if (unlikely(*max_len <= Fh_tail)) {
AuWarn1("NFSv2 client (max_len %d)?\n", *max_len);
goto out;
}
err = FILEID_ROOT;
if (IS_ROOT(dentry)) {
AuDebugOn(dentry->d_inode->i_ino != AUFS_ROOT_INO);
goto out;
}
err = -EIO;
h_parent = NULL;
sb = dentry->d_sb;
aufs_read_lock(dentry, AuLock_FLUSH | AuLock_IR);
parent = dget_parent(dentry);
di_read_lock_parent(parent, !AuLock_IR);
inode = dentry->d_inode;
AuDebugOn(!inode);
#ifdef CONFIG_AUFS_DEBUG
if (unlikely(!au_opt_test(au_mntflags(sb), XINO)))
AuWarn1("NFS-exporting requires xino\n");
#endif
bend = au_dbtaildir(parent);
for (bindex = au_dbstart(parent); bindex <= bend; bindex++) {
h_parent = au_h_dptr(parent, bindex);
if (h_parent) {
dget(h_parent);
break;
}
}
if (unlikely(!h_parent))
goto out_unlock;
err = -EPERM;
br = au_sbr(sb, bindex);
h_sb = br->br_mnt->mnt_sb;
if (unlikely(!h_sb->s_export_op)) {
AuErr1("%s branch is not exportable\n", au_sbtype(h_sb));
goto out_dput;
}
fh[Fh_br_id] = br->br_id;
fh[Fh_sigen] = au_sigen(sb);
encode_ino(fh + Fh_ino, inode->i_ino);
encode_ino(fh + Fh_dir_ino, parent->d_inode->i_ino);
fh[Fh_igen] = inode->i_generation;
*max_len -= Fh_tail;
fh[Fh_h_type] = exportfs_encode_fh(h_parent, (void *)(fh + Fh_tail),
max_len,
/*connectable or subtreecheck*/0);
err = fh[Fh_h_type];
*max_len += Fh_tail;
/* todo: macros? */
if (err != 255)
err = 99;
else
AuWarn1("%s encode_fh failed\n", au_sbtype(h_sb));
out_dput:
dput(h_parent);
out_unlock:
di_read_unlock(parent, !AuLock_IR);
dput(parent);
aufs_read_unlock(dentry, AuLock_IR);
out:
if (unlikely(err < 0))
err = 255;
return err;
}
static
struct dentry *decode_by_path(struct super_block *sb, aufs_bindex_t bindex,
ino_t ino, __u32 *fh, int fh_len,
struct au_nfsd_si_lock *nsi_lock)
{
struct dentry *dentry, *h_parent, *root;
struct super_block *h_sb;
char *pathname, *p;
struct vfsmount *h_mnt;
struct au_branch *br;
int err;
struct path path;
br = au_sbr(sb, bindex);
/* au_br_get(br); */
h_mnt = br->br_mnt;
h_sb = h_mnt->mnt_sb;
/* todo: call lower fh_to_dentry()? fh_to_parent()? */
h_parent = exportfs_decode_fh(h_mnt, (void *)(fh + Fh_tail),
fh_len - Fh_tail, fh[Fh_h_type],
h_acceptable, /*context*/NULL);
dentry = h_parent;
if (unlikely(!h_parent || IS_ERR(h_parent))) {
AuWarn1("%s decode_fh failed, %ld\n",
au_sbtype(h_sb), PTR_ERR(h_parent));
goto out;
}
dentry = NULL;
if (unlikely(au_test_anon(h_parent))) {
AuWarn1("%s decode_fh returned a disconnected dentry\n",
au_sbtype(h_sb));
goto out_h_parent;
}
dentry = ERR_PTR(-ENOMEM);
pathname = (void *)__get_free_page(GFP_NOFS);
if (unlikely(!pathname))
goto out_h_parent;
root = sb->s_root;
path.mnt = h_mnt;
di_read_lock_parent(root, !AuLock_IR);
path.dentry = au_h_dptr(root, bindex);
di_read_unlock(root, !AuLock_IR);
p = au_build_path(h_parent, &path, pathname, PAGE_SIZE, sb);
dentry = (void *)p;
if (IS_ERR(p))
goto out_pathname;
si_read_unlock(sb);
err = vfsub_kern_path(p, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
dentry = ERR_PTR(err);
if (unlikely(err))
goto out_relock;
dentry = ERR_PTR(-ENOENT);
AuDebugOn(au_test_anon(path.dentry));
if (unlikely(!path.dentry->d_inode))
goto out_path;
if (ino != path.dentry->d_inode->i_ino)
dentry = au_lkup_by_ino(&path, ino, /*nsi_lock*/NULL);
else
dentry = dget(path.dentry);
out_path:
path_put(&path);
out_relock:
if (unlikely(si_nfsd_read_lock(sb, nsi_lock) < 0))
if (!IS_ERR(dentry)) {
dput(dentry);
dentry = ERR_PTR(-ESTALE);
}
out_pathname:
free_page((unsigned long)pathname);
out_h_parent:
dput(h_parent);
out:
/* au_br_put(br); */
AuTraceErrPtr(dentry);
return dentry;
}
/* todo: return with unlocked? */
struct inode *au_new_inode(struct dentry *dentry, int must_new)
{
struct inode *inode, *h_inode;
struct dentry *h_dentry;
struct super_block *sb;
struct mutex *mtx;
ino_t h_ino, ino;
int err;
aufs_bindex_t bstart;
sb = dentry->d_sb;
bstart = au_dbstart(dentry);
h_dentry = au_h_dptr(dentry, bstart);
h_inode = h_dentry->d_inode;
h_ino = h_inode->i_ino;
/*
* stop 'race'-ing between hardlinks under different
* parents.
*/
mtx = NULL;
if (!S_ISDIR(h_inode->i_mode))
mtx = &au_sbr(sb, bstart)->br_xino.xi_nondir_mtx;
new_ino:
if (mtx)
mutex_lock(mtx);
err = au_xino_read(sb, bstart, h_ino, &ino);
inode = ERR_PTR(err);
if (unlikely(err))
goto out;
if (!ino) {
ino = au_xino_new_ino(sb);
if (unlikely(!ino)) {
inode = ERR_PTR(-EIO);
goto out;
}
}
AuDbg("i%lu\n", (unsigned long)ino);
inode = au_iget_locked(sb, ino);
err = PTR_ERR(inode);
if (IS_ERR(inode))
goto out;
AuDbg("%lx, new %d\n", inode->i_state, !!(inode->i_state & I_NEW));
if (inode->i_state & I_NEW) {
/* verbose coding for lock class name */
if (unlikely(S_ISLNK(h_inode->i_mode)))
au_rw_class(&au_ii(inode)->ii_rwsem,
au_lc_key + AuLcSymlink_IIINFO);
else if (unlikely(S_ISDIR(h_inode->i_mode)))
au_rw_class(&au_ii(inode)->ii_rwsem,
au_lc_key + AuLcDir_IIINFO);
else /* likely */
au_rw_class(&au_ii(inode)->ii_rwsem,
au_lc_key + AuLcNonDir_IIINFO);
ii_write_lock_new_child(inode);
err = set_inode(inode, dentry);
if (!err) {
unlock_new_inode(inode);
goto out; /* success */
}
/*
* iget_failed() calls iput(), but we need to call
* ii_write_unlock() after iget_failed(). so dirty hack for
* i_count.
*/
atomic_inc(&inode->i_count);
iget_failed(inode);
ii_write_unlock(inode);
au_xino_write(sb, bstart, h_ino, /*ino*/0);
/* ignore this error */
goto out_iput;
} else if (!must_new && !IS_DEADDIR(inode) && inode->i_nlink) {
/*
* horrible race condition between lookup, readdir and copyup
* (or something).
*/
if (mtx)
mutex_unlock(mtx);
err = reval_inode(inode, dentry);
if (unlikely(err < 0)) {
mtx = NULL;
goto out_iput;
}
if (!err) {
mtx = NULL;
goto out; /* success */
} else if (mtx)
mutex_lock(mtx);
}
if (unlikely(au_test_fs_unique_ino(h_dentry->d_inode)))
AuWarn1("Warning: Un-notified UDBA or repeatedly renamed dir,"
" b%d, %s, %pd, hi%lu, i%lu.\n",
bstart, au_sbtype(h_dentry->d_sb), dentry,
(unsigned long)h_ino, (unsigned long)ino);
ino = 0;
err = au_xino_write(sb, bstart, h_ino, /*ino*/0);
if (!err) {
iput(inode);
if (mtx)
mutex_unlock(mtx);
goto new_ino;
}
out_iput:
iput(inode);
inode = ERR_PTR(err);
out:
if (mtx)
mutex_unlock(mtx);
return inode;
}
/* todo: return with unlocked? */
struct inode *au_new_inode(struct dentry *dentry, int must_new)
{
struct inode *inode, *h_inode;
struct dentry *h_dentry;
struct super_block *sb;
struct mutex *mtx;
ino_t h_ino, ino;
int err, match;
aufs_bindex_t bstart;
sb = dentry->d_sb;
bstart = au_dbstart(dentry);
h_dentry = au_h_dptr(dentry, bstart);
h_inode = h_dentry->d_inode;
h_ino = h_inode->i_ino;
/*
* stop 'race'-ing between hardlinks under different
* parents.
*/
mtx = NULL;
if (!S_ISDIR(h_inode->i_mode))
mtx = &au_sbr(sb, bstart)->br_xino.xi_nondir_mtx;
new_ino:
if (mtx)
mutex_lock(mtx);
err = au_xino_read(sb, bstart, h_ino, &ino);
inode = ERR_PTR(err);
if (unlikely(err))
goto out;
if (!ino) {
ino = au_xino_new_ino(sb);
if (unlikely(!ino)) {
inode = ERR_PTR(-EIO);
goto out;
}
}
AuDbg("i%lu\n", (unsigned long)ino);
inode = au_iget_locked(sb, ino);
err = PTR_ERR(inode);
if (IS_ERR(inode))
goto out;
AuDbg("%lx, new %d\n", inode->i_state, !!(inode->i_state & I_NEW));
if (inode->i_state & I_NEW) {
ii_write_lock_new_child(inode);
err = set_inode(inode, dentry);
if (!err) {
unlock_new_inode(inode);
goto out; /* success */
}
ii_write_unlock(inode);
iget_failed(inode);
goto out_err;
} else if (!must_new) {
/*
* horrible race condition between lookup, readdir and copyup
* (or something).
*/
if (mtx)
mutex_unlock(mtx);
err = reval_inode(inode, dentry, &match);
if (!err) {
mtx = NULL;
goto out; /* success */
} else if (match) {
mtx = NULL;
goto out_iput;
} else if (mtx)
mutex_lock(mtx);
}
if (unlikely(au_test_fs_unique_ino(h_dentry->d_inode)))
AuWarn1("Warning: Un-notified UDBA or repeatedly renamed dir,"
" b%d, %s, %.*s, hi%lu, i%lu.\n",
bstart, au_sbtype(h_dentry->d_sb), AuDLNPair(dentry),
(unsigned long)h_ino, (unsigned long)ino);
ino = 0;
err = au_xino_write(sb, bstart, h_ino, /*ino*/0);
if (!err) {
iput(inode);
if (mtx)
mutex_unlock(mtx);
goto new_ino;
}
out_iput:
iput(inode);
out_err:
inode = ERR_PTR(err);
out:
if (mtx)
mutex_unlock(mtx);
return inode;
}
static struct dentry *
aufs_decode_fh(struct super_block *sb, __u32 *fh, int fh_len, int fh_type,
int (*acceptable)(void *context, struct dentry *de),
void *context)
{
struct dentry *dentry;
ino_t ino, dir_ino;
aufs_bindex_t bindex;
struct au_nfsd_si_lock nsi_lock = {
.sigen = fh[Fh_sigen],
.br_id = fh[Fh_br_id],
.force_lock = 0
};
LKTRTrace("%d, fh{br_id %u, sigen %u, i%u, diri%u, g%u}\n",
fh_type, fh[Fh_br_id], fh[Fh_sigen], fh[Fh_ino],
fh[Fh_dir_ino], fh[Fh_igen]);
AuDebugOn(fh_len < Fh_tail);
dentry = ERR_PTR(-ESTALE);
/* branch id may be wrapped around */
bindex = si_nfsd_read_lock(sb, &nsi_lock);
if (unlikely(bindex < 0))
goto out;
nsi_lock.force_lock = 1;
/* is this inode still cached? */
ino = decode_ino(fh + Fh_ino);
AuDebugOn(ino == AUFS_ROOT_INO);
dir_ino = decode_ino(fh + Fh_dir_ino);
dentry = decode_by_ino(sb, ino, dir_ino);
if (IS_ERR(dentry))
goto out_unlock;
if (dentry)
goto accept;
/* is the parent dir cached? */
dentry = decode_by_dir_ino(sb, ino, dir_ino, &nsi_lock);
if (IS_ERR(dentry))
goto out_unlock;
if (dentry)
goto accept;
/* lookup path */
dentry = decode_by_path(sb, bindex, ino, fh, fh_len, &nsi_lock);
if (IS_ERR(dentry))
goto out_unlock;
if (unlikely(!dentry))
goto out_unlock;
accept:
LKTRLabel(accept);
if (dentry->d_inode->i_generation == fh[Fh_igen]
&& acceptable(context, dentry))
goto out_unlock; /* success */
LKTRLabel(stale);
dput(dentry);
dentry = ERR_PTR(-ESTALE);
out_unlock:
LKTRLabel(out_unlock);
si_read_unlock(sb);
out:
LKTRLabel(out);
if (0 && IS_ERR(dentry))
dentry = ERR_PTR(-ESTALE);
AuTraceErrPtr(dentry);
return dentry;
}
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 24)
static struct dentry *
aufs_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len,
int fh_type)
{
return aufs_decode_fh(sb, fid->raw, fh_len, fh_type, h_acceptable,
/*context*/NULL);
}
#endif /* KERNEL_VERSION */
/* ---------------------------------------------------------------------- */
static int aufs_encode_fh(struct dentry *dentry, __u32 *fh, int *max_len,
int connectable)
{
int err;
aufs_bindex_t bindex, bend;
struct super_block *sb, *h_sb;
struct inode *inode;
struct dentry *parent, *h_parent;
struct au_branch *br;
LKTRTrace("%.*s, max %d, conn %d\n",
AuDLNPair(dentry), *max_len, connectable);
AuDebugOn(au_test_anon(dentry));
parent = NULL;
err = -ENOSPC;
if (unlikely(*max_len <= Fh_tail)) {
AuWarn1("NFSv2 client (max_len %d)?\n", *max_len);
goto out;
}
err = 0; //FILEID_ROOT;
if (IS_ROOT(dentry)) {
AuDebugOn(dentry->d_inode->i_ino != AUFS_ROOT_INO);
goto out;
}
err = -EIO;
h_parent = NULL;
sb = dentry->d_sb;
aufs_read_lock(dentry, AuLock_FLUSH | AuLock_IR);
parent = dget_parent(dentry);
di_read_lock_parent(parent, !AuLock_IR);
inode = dentry->d_inode;
AuDebugOn(!inode);
#ifdef CONFIG_AUFS_DEBUG
{
unsigned int mnt_flags = au_mntflags(sb);
if (unlikely(!au_opt_test_xino(mnt_flags)))
AuWarn1("NFS-exporting requires xino\n");
if (unlikely(0 && !au_opt_test(mnt_flags, UDBA_INOTIFY)))
AuWarn1("udba=inotify is recommended "
"for NFS-exporting\n");
}
#endif
bend = au_dbtaildir(parent);
for (bindex = au_dbstart(parent); bindex <= bend; bindex++) {
h_parent = au_h_dptr(parent, bindex);
if (h_parent) {
dget(h_parent);
break;
}
}
if (unlikely(!h_parent))
goto out_unlock;
LKTRTrace("b%d\n", bindex);
err = -EPERM;
br = au_sbr(sb, bindex);
h_sb = br->br_mnt->mnt_sb;
if (unlikely(!h_sb->s_export_op)) {
AuErr1("%s branch is not exportable\n", au_sbtype(h_sb));
goto out_dput;
}
fh[Fh_br_id] = br->br_id;
fh[Fh_sigen] = au_sigen(sb);
encode_ino(fh + Fh_ino, inode->i_ino);
encode_ino(fh + Fh_dir_ino, parent->d_inode->i_ino);
fh[Fh_igen] = inode->i_generation;
#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 24)
/* it should be set at exporting time */
if (unlikely(!h_sb->s_export_op->find_exported_dentry)) {
AuWarn("set default find_exported_dentry for %s\n",
au_sbtype(h_sb));
h_sb->s_export_op->find_exported_dentry = find_exported_dentry;
}
#endif
*max_len -= Fh_tail;
fh[Fh_h_type] = au_call_encode_fh(h_parent, fh + Fh_tail, max_len,
/*connectable or subtreecheck*/0);
err = fh[Fh_h_type];
*max_len += Fh_tail;
/* todo: macros? */
if (err != 255)
err = 99;
else
AuWarn1("%s encode_fh failed\n", au_sbtype(h_sb));
out_dput:
dput(h_parent);
out_unlock:
di_read_unlock(parent, !AuLock_IR);
dput(parent);
aufs_read_unlock(dentry, AuLock_IR);
out:
AuTraceErr(err);
if (unlikely(err < 0))
err = 255;
return err;
}
